FINAL Mitigated Negative Declaration/Initial Study Heart

FINAL

Mitigated Negative Declaration/Initial Study

Heart of the City Specific Plan Amendment

for Rancho Coronado

City of San Marcos, California

April 2014

Table of Contents

Heart of the City Specific Plan Amendment-Rancho Coronado i City of San Marcos

Final Initial Study/Mitigated Negative Declaration April 2014

TABLE OF CONTENTS

1.0 INTRODUCTION AND SUMMARY ......................................................................................... 1-1

2.0 CORRECTIONS AND ADDITIONS ........................................................................................... 2-1

2.1 REVISED AND SUPPLEMENTAL TEXT................................................................................ 2-1

3.0 RESPONSE TO WRITTEN COMMENTS ................................................................................... 3-1

4.0 MITIGATION MONITORING AND REPORTING PROGRAM ..................................................... 4-1

List of Tables

Table 3-1. Comment Letters ................................................................................................................... 3-1

Table 4-1. Mitigation Measures .............................................................................................................. 4-2

Table 4-2. Design Considerations for the Project ................................................................................. 4-14

Table of Contents

Heart of the City Specific Plan Amendment-Rancho Coronado ii City of San Marcos


THIS PAGE INTENTIONALLY LEFT BLANK.

1.0 Introduction and Summary

Heart of the City Specific Plan Amendment-Rancho Coronado 1-1 City of San Marcos


1.0 INTRODUCTION AND SUMMARY

This Final Initial Study and Mitigated Negative Declaration (IS/MND) has been prepared in accordance

with the California Environmental Quality Act (CEQA) as amended (Public Resources Code Section 21000

et seq.) and the CEQA Guidelines (California Administrative Code Section 15000 et seq.).

CEQA Guidelines Section 15074(b) and (d) state:

“(b) Prior to approving a project, the decision-making body of the lead agency shall

consider the proposed negative declaration or mitigated negative declaration together

with any comments received during the public review process. The decision-making

body shall adopt the proposed negative declaration or mitigated negative declaration

only if it finds on the basis of the whole record before it (including the initial study and

any comments received), that there is no substantial evidence that the project will have

a significant effect on the environment and that the negative declaration or mitigated

negative declaration reflects the lead agency's independent judgment and analysis.”

“(d) When adopting a mitigated negative declaration, the lead agency shall also adopt a

program for reporting on or monitoring the changes which it has either required in the

project or made a condition of approval to mitigate or avoid significant environmental

effects.”

In accordance with this requirement, the Heart of the City Specific Plan Amendment (Rancho Coronado)

IS/MND is comprised of the following:

• Draft Initial Study and Mitigated Negative Declaration February 2014 (SCH No. 2014021007);

• This Final IS/MND document, April 2014, that incorporates the information required by §15074

(included in this document); and

• A Mitigation Monitoring and Reporting Program (included in this document).

Format of the Final IS/MND

This document is organized as follows:

Section 1.0 Introduction and Summary

This section describes CEQA requirements and content of this Final IS/MND.

Section 2.0 Corrections and Additions

This section provides a list of those revisions made to the Draft IS/MND text as a result

of comments received and/or errors and omissions discovered subsequent to release of

the Draft IS/MND for public review.

1.0 Introduction and Summary



Section 3.0 Responses to Comment Letters Received on the Draft IS/MND

This section provides copies of the comment letters received and individual responses

to written comments.

Section 4.0 Mitigation Monitoring and Reporting Program

This section provides a program of monitoring or reporting to ensure that the

provisions or revisions are complied with during implementation of the project.

2.0 Corrections and Additions



2.0 CORRECTIONS AND ADDITIONS

This section contains revisions to information included in the Draft IS/MND (February 2014) based upon

additional or revised information required to prepare a response to a specific comment. Please see

copies of the letters and responses in Section 3.0, Responses and Comments of this Final IS/MND, as

applicable.

2.1 REVISED AND SUPPLEMENTAL TEXT

The following table summarizes the changes to the Draft IS/MND. These changes were based upon

public comments on the Draft IS/MND, incorporation of the Water and Sewer Study (Vallecitos Water

District 2014) and the Least Bell’s Vireo (LBV) Survey (Helix 2012) into the Final IS/MND, as well as

additional clean up items due to project refinements. The complete Water and Sewer Study is included

as Appendix N of the Final IS/MND and the LBV survey is included as Appendix O. None of the analysis

conclusions for water and sewer changed. Impacts remain less than significant.

Pages IS/MND Section Summary of Change

3 1.F – Project Entitlements Discretionary actions with associated reference numbers updated in

the document. Ministerial approval also identified.

8 II. Project Descriptions Information regarding boundary adjustment for sewer service.

11 Table 2 Clarified the requirements for pipeline improvements for the project.

40/41 IV-c – Cultural Resources Revisions to text and Table 7a to note mitigation requirement for

detention basin (0.2 acres).

51 V.b – Cultural Resources Added information on what tribes provided correspondence for the

project.

51 - 53 V.b – Cultural Resources Minor modification to cultural resources mitigation measures based

upon input from the Tribes and the San Diego County Archaeological

Society.

113 XVI.b – Traffic Added statement about assumptions for ramp meter flow rates.

120/121 XVI.b – Traffic Ramp meter delay analysis refined. Based upon the new analysis, the

project would not have a significant impact at the Twin Oaks Valley

Road / SR-78 Eastbound On-Ramp in the Horizon Year 2030

condition. Mitigation measures TR-3 would no longer be required.

124/125 XVII.b – Utilities and Service

Systems

Updated water demand calculation on Table 41 and associated text.

125 XVII.b – Utilities and Service

Systems

Modified water storage conclusion to note the project decreases

demand compared to what was assumed for the project site in the

2008 VWD Master Plan and no further storage upgrades are needed.

126 XVII.b – Utilities and Service

Systems

Added Table 42, which shows the wastewater flows for the project

site for the 2008 VWD Master Plan and the proposed project.

Refined wastewater collection system analysis text to note the

pipeline improvements required for the project.

128 XVII.d – Utilities and Service

Systems

Updated the water supply analysis to note the water demand for the

project and that the expected demand is less than what was




Pages IS/MND Section Summary of Change

anticipated per the VWD 2008 Master Plan.

138 VIII – Mitigated Negative

Declaration

Updated mitigation measures MM-BIO-1A to reflect the increase of

mitigation from 1.07 to 1.27 acres to reflect detention basin

mitigation requirements.

140-142 VIII – Mitigated Negative

Declaration

Updated cultural resources mitigation measures to reflect input from

the Tribes and San Diego County Archaeological Society.

144 A VIII – Mitigated Negative

Declaration

Mitigation measures MM-TR-3 no longer required due to refinement

of analysis.

Appendix N Appendices Added Water and Sewer Study (VWD 2014) to the Technical

Appendices.

Appendix O Appendices Added Least Bell’s Vireo report (Helix 2012) to the Technical

Appendices.

Ramp Meter Analysis Refinement

Based upon a refinement in the ramp meter assumptions and analysis, the project is no longer

identified as having an impact in Horizon Year 2030 at the Twin Oaks Valley Road / SR-78 Eastbound On-

Ramp and mitigation measure MM-TR-3 is no longer required. The ramp meter analysis has been

refined in the CEQA document and reads as follows (strike out for removed text/ underline for added

text).

Revised text – pages 120 and 121:

The results of the ramp metering analysis show that under Horizon Year conditions, the addition of

project-related traffic to the Twin Oaks Valley Road / SR-78 Eastbound On-Ramp during the p.m. peak

hour is forecast to result in a ramp meter delay that exceeds the policy threshold of 15 minutes. The

increase in ramp meter delay associated with project-related traffic is forecast to result in an increase in

delay that exceeds the significant impact threshold of 2 minutes according to the SANTEC/ITE TIS

Guidelines.

As previously discussed, the existing ramp meter flow rates were used for all future analysis scenarios.

This assumption provided a conservative analysis because there are planned capacity improvements on

eastbound SR-78 through the study area that would likely allow for adjustments in the future ramp

meter rate at the Twin Oaks Valley Road Eastbound On-Ramp.

The planned freeway improvements for eastbound SR-78 through the study area are listed below:

• One new auxiliary lane will be provided, extending from immediately upstream of the San

Marcos Boulevard On-Ramp and connecting with the existing auxiliary lane that is currently

provided from the San Marcos Boulevard eastbound on-ramp to the Twin Oaks Valley Road

eastbound off-ramp.

• A second eastbound auxiliary lane will be provided that will begin at the San Marcos Boulevard

eastbound on-ramp and will terminate at the Twin Oaks Valley Road eastbound off-ramp. The




first auxiliary lane will be extended east though the Twin Oaks Valley Road interchange and will

terminate at the Woodland Parkway/Barham Drive eastbound off-ramp.

• The lengths of the San Marcos Boulevard and Twin Oaks Valley Road eastbound on-ramps

would be increased to provide longer acceleration and merging distances from the ramp meters

to the freeway ramp gore points.

• A new eastbound auxiliary lane will be provided from the reconfigured Barham Drive/Woodland

Parkway interchange that will extend east to connect with the existing auxiliary lane that

currently begins immediately east of the SPRINTER overcrossing.

The improvements listed above are planned to be completed prior to the year 2030 and are

included in the Horizon Year 2030 conditions analysis.

The existing ramp meter flow rate of 570 vehicles per hour during the p.m. peak period equates to

approximately 9.5 cycles per minute at the Twin Oaks Valley Road Eastbound On-Ramp. Based on

the existing p.m. ramp meter rate, the forecast ramp meter delay is 17 minutes under Horizon Year

2030 conditions with the proposed project. If the p.m. ramp meter flow rate were adjusted slightly

to 600 vehicles per hour, the forecast ramp meter delay under 2030 conditions with the project

would decrease to 13 minutes, which is equivalent to the forecast p.m. ramp meter delay without

the project. The adjustment to 600 vehicles per hour is equivalent to 10 cycles per minute, a

difference of only one-half cycle per minute.

This adjustment in the p.m. ramp meter rate should be feasible based on the expected

improvement in freeway operations when the planned improvements are completed. Therefore, it

is reasonable to expect that the planned improvements along eastbound SR-78 would reduce the

identified ramp meter impact to a level that is less than significant, and no mitigation measures

would be required.

deficient ramp meter delay under Horizon Year 2030 conditions. Therefore, the project results in a

significant impact at the Twin Oaks Valley Road / SR-78 Eastbound On-Ramp and mitigation

measures are required (Impact TR-3). There are two options to reduce this impact to below a level

of significance:

MM-TR-3 One of the following options shall be implemented at the intersection of Twin Oaks

Valley Road / SR-78 EB On-Ramp:

• Adjusting the ramp meter rate to accommodate the increase in demand at

the on-ramp; or

• Converting the existing HOV lane to a third SOV lane on the on-ramp to

increase on-ramp capacity.

Implementation of mitigation measure MM-TR-3, which will be required as a condition of project

approval will reduce the deficient ramp meter delay under the Horizon Year 2030 conditions at the

Twin Oaks Valley Road / SR-78 Eastbound On-Ramp during the p.m. peak hour to below a level of

significance.

3.0 Response to Written Comments



3.0 RESPONSE TO WRITTEN COMMENTS

Section 3.0 contains responses to all comment letters received on the February 2014 Draft IS/MND. A

total of seven comment letters were received during the comment period, which closed March 7, 2014

(Table 3-1).

Table 3-1. Comment Letters

Number Letter Preparer Date

1 Office of Planning and Research – State Clearinghouse 3/7/14

2 United States Fish and Wildlife Service/California Department of Fish and Game 3/7/14

3 Native American Heritage Commission 3/4/14

4 Vallecitos Water District 2/25/14

5 San Diego Archeological Society 3/5/14

6 San Luis Rey Band of Mission Indians 3/5/14

7 U.S. Department of Homeland Security/FEMA 3/11/14




1-1







1-2




1-2

Cont.




Letter 1

Office of Planning and Research / State Clearinghouse

1-1 This comment states that the State Clearinghouse submitted the MND to select state agencies

for review. The letter also confirms that the City complied with the State Clearinghouse review

requirements for draft environmental documents pursuant to the California Environmental

Quality Act. In closing, this comment does not raise any environmental issues so no further

response is warranted.

1-2 This attachment to the letter from OPR/State Clearinghouse is comments from the Native

American Heritage Commission (NAHC). The NAHC submitted these same comments directly to

the city. Please see comment letter




2-1

2-2

2-4

2-3

2-5




2-6




Letter 2

United States Fish and Wildlife Service/California Department of Fish and Wildlife

2-1 This comment provides introductory remarks. This comment does not raise any specific issues

on the environmental document and no additional response is warranted.

2-2 This comment request tables showing changes to the habitat types within the HLP. The

following tables are provided based upon this comment:

Proposed Hardline Vegetation Changes

Vegetation Type

Removed from

Adopted Hardline Area

(acres)

Added to

Adopted Hardline Area

(acres)

Total

Difference

(acres)

Sensitive

Southern riparian forest 0.00 0.12 0.12

Coastal sage scrub 0.00 2.40 2.40

Southern mixed chaparral 0.00 0.00 0.00

Subtotal Sensitive 0.00 2.52 +2.52

Non-Sensitive

Eucalyptus woodland 0.20 1.00 0.80

Disturbed 0.40 0.20 -0.20

Subtotal Non-sensitive 0.60 1.20 +0.70

TOTAL 0.60 3.72 +3.12

Comparison of Vegetation Communities in the Approved HLP Preserve vs. Proposed HLP Preserve

Vegetation Community

Existing Preserve

(acres)

Proposed Preserve

(acres)

Change

(acres)

Southern riparian forest (61300) 0.58

0.701

0.121

Diegan coastal sage scrub (32500) 89.02

91.42

2.4

Southern mixed chaparral (37120) 11.5 11.5 0

Eucalyptus woodland (79000) 2.4 3.2 0.8

Disturbed habitat (11300) 3.63

3.43

(0.2)

Total 107.1 110.24 3.1

4

1Does not include acres that will also be restored within the riparian mitigation area within the HLP Preserve.

2Does not include 2.4 acres of sage scrub restoration required by the HLP.

32.4 acres will be restored to sage scrub as required by the HLP.

4Does not include additional acres conserved as part of wetland restoration onsite outside of the HLP Preserve.

2-3 The 2012 Least Bell’s Vireo (LBV) survey report is included as Appendix O of the Final IS/MND.

The results of the LBV survey were included in the Draft IS/MND in the Biological Resources

section.




2-4 The City does not see the need for a specific drought contingency plan. If the project has not

met success criteria as a result of drought conditions, the applicant would need to continue the

restoration effort unless otherwise agreed to by the resource agencies. If success criteria have

been met at the end of five years, the restoration would have been off of irrigation for a

minimum of two years, and any affects of a drought would already be accounted for in meeting

(or not meeting) success criteria. No changes were made to the Final IS/MND based upon this

comment.

2-5 This comment provides closing remarks and does not raise any additional comments on the

environmental document.




3-1

3-2

3-3

3-4




3-5

3-6

3-8

3-7







Letter 3

Native American Heritage Commission

3-1 This comment notes the project subject to SB-18. The City sent out letters to the Native

American community to and has been consulting with interested Tribes and their input has

been incorporated into the cultural resources mitigation measures.

3-2 Based upon the cultural resources study prepared for the project (ASM 2014), there are no

cultural resources on the project site.

3-3 In order to account for the potential for encountering unidentified cultural resources, mitigation

was included in the MND requiring an archaeological and Native American monitor. Please see

mitigation measures. These measures are also provided here:

MM-CR-1 An archeological monitor and a Luiseño Native American monitor shall be

present during all earth moving and grading activities to assure that any

potential cultural resources, including tribal, found during project grading be

protected.

MM CR-2 Prior to beginning project construction, the Project Applicant shall retain a San

Diego County qualified archaeological monitor to monitor all ground-disturbing

activities in an effort to identify any unknown archaeological resources. Any

newly discovered cultural resource deposits shall be subject to cultural

resources evaluation which shall include archaeological documentation, analysis

and report generation.

MM-CR-3 At least 30 days prior to beginning project construction, the Project Applicant

shall enter into a Cultural Resource Treatment and Monitoring Agreement (also

known as a pre-excavation agreement) with a Luiseño Tribe. The Agreement

shall address the treatment of known cultural resources, the designation,

responsibilities, and participation of professional Native American Tribal

monitors during grading, excavation and ground disturbing activities; project

grading and development scheduling; terms of compensation for the monitors;

and treatment and final disposition of any cultural resources, sacred sites, and

human remains discovered on site.

MM-CR-4 Prior to beginning project construction, the Project Archaeologist shall file a

pre-grading report with the City to document the proposed methodology for

grading activity observation, which will be determined in consultation with the

Luiseño Tribe referenced in MM-CR-3. . Said methodology shall include the

requirement for a qualified archaeological monitor to be present and to have

the authority to stop and redirect grading activities. In accordance with the

agreement required in MM-CR-3, the archaeological monitor’s authority to stop

and redirect grading will be exercised in consultation with the Luiseño Native

American monitor in order to evaluate the significance of any archaeological

resources discovered on the property. Tribal and archaeological monitors shall




be allowed to monitor all grading, excavation, and groundbreaking activities,

and shall also have the authority to stop and redirect grading activities.

MM-CR-5 The landowner shall relinquish ownership of all cultural resources collected

during the grading monitoring program and from any previous archaeological

studies or excavations on the project site to the appropriate Tribe for proper

treatment and disposition per the Cultural Resource Treatment and Monitoring

Agreement referenced in MM-CR-3. All cultural materials that are deemed by

the Tribe to be associated with burial and/or funerary goods will be repatriated

to the Most Likely Descendant as determined by the Native American Heritage

Commission per California Public Resources Code Section 5097.98.

MM-CR-6 All sacred sites, should they be encountered within the project area, shall be

avoided and preserved as the preferred mitigation, if feasible.

MM-CR-7 If human remains are encountered, California Health and Safety Code Section

7050.5 states that no further disturbance shall occur until the San Diego County

Coroner has made the necessary findings as to origin. Further, pursuant to

California Public Resources Code Section 5097.98(b) remains shall be left in

place and free from disturbance until a final decision as to the treatment and

disposition has been made. Suspected Native American remains shall be

examined in the field and kept in a secure location at the site If the San Diego

County Coroner determines the remains to be Native American, the

Native American Heritage Commission (NAHC) must be contacted within

24 hours. The NAHC must them immediately notify the “most likely

descendant(s)” of receiving notification of the discovery. The most likely

descendants(s) shall then make recommendations within 48 hours, and engage

in consultation concerning treatment of remains as provided in Public

Resources Code 5097.98.3.

MM-CR-8 If inadvertent discoveries of subsurface archaeological/cultural resources are

discovered during grading, the Developer, the project archaeologist, and the

Luiseño Tribe under agreement with the landowner described in MM-CR-3 shall

assess the significance of such resources and shall meet and confer regarding

the mitigation for such resources. Pursuant to California Public Resources Code

Section 21083.2(b) avoidance is the preferred method of preservation for

archaeological resources. If the Developer, the project archaeologist and the

Tribe cannot agree on the significance of mitigation for such resources, these

issues will be presented to the Planning Director for decision. The Planning

Director shall make a determination based upon the provisions of the California

Environmental Quality Act with respect to archaeological resources and shall

take into account the religious beliefs, customs, and practices of the Tribe.

Notwithstanding any other rights available under law, the decision of the

Planning Director shall be appealable to the Planning Commission and/or City

Council.




3-4 There is no federal nexus with the project thus the National Environmental Policy Act and

Section 106 of the National Historic Preservation Act.

3-5 A cultural resources report was prepared for the project and no resources were identified on

the project site. Thus no site forms were prepared.

3-6 As part of the cultural resources report preparation, letters were sent to the appropriate Native

American contact for the project. Additionally, the City reached out the local Tribes as part of

the SB18 process.

3-7 Implementation of mitigation measures identified for the project (MM-CR-1 through MM-CR-8)

will be required as a condition of project approval. Additionally, a Mitigation, Monitoring and

Reporting Program (MMRP) will be adopted for the project. The mitigation requires

coordination with the culturally affiliated Native Americans if resources are identified during

project grading.

3-8 Mitigation Measure MM-CR-8 identifies the steps that shall be implemented in the event of

accidental discovery of any human remains on the site.




4-1

4-2




4-4

4-3

4-2

Cont.

4-5




4-6

4-5

Cont.

4-8

4-7

4-9

4-10







Letter 4

Vallecitos Water District

4-1 This comment states that the conclusion regarding wastewater treatment requirements of the

applicable Regional Water Quality Control Board is acceptable. This comment does not raise any

additional issues with the environmental document; therefore, no additional response is

warranted.

4-2 The wastewater flow generation quantities have been updated in the Final IS/MND. Please see

Table 42. As note by this comment, this results in deficiencies in the District’s infrastructure.

The project will pay Wastewater Facility Fees per Ordinance No. 177 as well as Wastewater

Capital Facility Fees per Ordinance No. 176. These fee payments are identified in Table 1 as

design features for the project. Additionally, as noted in Table 1 of the Final IS/MND, the

project will upsize approximately 2,700 feet of an existing 8-inch wastewater collection pipe in

Craven Road. The improvement includes 700 feet of 10-inch pipeline and 2,000 feet of 12-inch

pipeline. This meets the recommendations indentified in VWD’s letter.

4-3 This comment addresses threshold “c” under the Utilities and Services Systems analysis section

of the IS/MND. It addresses stormwater facilities and is not applicable to VWD, as noted in this

comment. This comment does not raise any additional issues with the environmental

document; therefore no additional response is warranted.

4-4 Water demand quantities have been updated in Table 41 of the Final IS/MND to reflect the

Water and Sewer Study prepared by VWD (2014). The project will install a new 14-inch

diameter water main loop from the intersection of Twin Oaks Valley Road and South Village

Drive to the existing 14-inch water main, approximately 1,100 feet north of South Lake Pump

Station. This is also noted as a project design feature in Table 1 of the Final IS/MND. The project

will also relocate a 14-inch water main that traverses the development, as requested by this

comment.

4-5 Please see response 4-2. The project will pay the fees identified in this comment (Wastewater

Impact Fees and Capital Facility Fees) as well as upsize the segments within Craven Road, as

identified in this comment.

4-6 The City recognizes that the project is within VWD’s district boundary for water service but will

need to be annexed in to VWD’s service boundary for sewer service. This is an intra-district

annexation and will not require LAFCO approval or process. This requirement has been

identified in the project description of the Final IS/MND. Please see page 8 of the Final IS/MND.

4-7 This comment address VWD’s existing access and pipeline easements. As a condition of project

approval the project applicant will be required to dedicate new easements that are acceptable

to VWD.

4-8 As a condition of project approval, the project applicant will be required to coordinate with

VWD to ensure that relocation and construction of physical access to South Lake Pump Station,

South Lake, and the dam will be provided. The access shall be approved by VWD.




4-9 Design and construction of the ultimate VWD spillway will be required as a condition of project

approval. The following language is included as a condition of approval for the project and a

note shall be placed on the final map reflecting this condition:

Prior to recordation of the final map, the applicant, Aggregate Pacific

Southwest, Inc. shall post a security for the design, permitting, construction,

and inspection of the ultimate South Lake spillway. The applicant, Hanson

Aggregate Pacific Southwest, Inc, shall obtain State Division of Safety of Dam

(DSOD) and Vallecitos Water District (VWD) approval of the South Lake Dam

ultimate spillway construction documents prior to 25% of residential building

permit issuance. No additional building permits will be issued without said

spillway approval. Furthermore, the applicant, Hanson Aggregate Pacific

Southwest, Inc., shall construct the South Lake Dam ultimate spillway prior to

75% of residential building permit issuance. No additional building permits will

be issued without said spillway construction. Security will be returned to the

applicant once the ultimate spillway construction has been accepted by the

jurisdictional agencies.

In addition, the applicant, Hanson Aggregate Pacific Southwest, Inc., shall

process a boundary adjustment with APN 222-190-02 (VWD) which results in

the spillway being located on VWD property. Said boundary adjustment shall

be recorded prior to construction of the ultimate spillway.

4-10 The City understands that VWD will not approve proposed grading on their access, easements

and spillway area until certain requirements are met to VWD’s satisfaction. The City is including

VWD’s requirement as conditions of project approval for the applicant.




5-3

5-1

5-2

5-4

5-5




5-6

5-5

Cont.




Letter 5

San Diego County Archeological Society

5-1 This comment provides introductory remarks and notes that the SDCAS reviewed the cultural

resources report and concurs with the recommendation for an archaeological and Native

American monitor.

5-2 This comment states that the SDCAS concurs with mitigation measures MM-CR-1, MM-CR-4,

MM-CR-6, MM-CR-7, and MM-CR-8 as written. It should be noted that based upon input from

local Tribes, there were some refinements to some of the mitigation measures. Tracked

changed version of the mitigation measures are included in the Final IS/MND. The final version

of the mitigation measures is presented here:

MM-CR-1 An archeological monitor and a Luiseño Native American monitor shall be

present during all earth moving and grading activities to assure that any

potential cultural resources, including tribal, found during project grading be

protected.



activities in an effort to identify any unknown archaeological resources. Any

newly discovered cultural resource deposits shall be subject to cultural

resources evaluation, which shall include archaeological documentation,

analysis and report generation.

MM-CR-3 At least 30 days prior to beginning project construction, the Project Applicant

shall enter into a Cultural Resource Treatment and Monitoring Agreement (also

known as a pre-excavation agreement) with a Luiseño Tribe. The Agreement

shall address the treatment of known cultural resources, the designation,

responsibilities, and participation of professional Native American Tribal

monitors during grading, excavation and ground disturbing activities; project

grading and development scheduling; terms of compensation for the monitors;

and treatment and final disposition of any cultural resources, sacred sites, and


MM-CR-4 Prior to beginning project construction, the Project Archaeologist shall file a

pre-grading report with the City to document the proposed methodology for

grading activity observation, which will be determined in consultation with the

Luiseño Tribe referenced in MM-CR-3. . Said methodology shall include the

requirement for a qualified archaeological monitor to be present and to have

the authority to stop and redirect grading activities. In accordance with the

agreement required in MM-CR-3, the archaeological monitor’s authority to stop

and redirect grading will be exercised in consultation with the Luiseño Native

American monitor in order to evaluate the significance of any archaeological

resources discovered on the property. Tribal and archaeological monitors shall




be allowed to monitor all grading, excavation, and groundbreaking activities,

and shall also have the authority to stop and redirect grading activities.

MM-CR-5 The landowner shall relinquish ownership of all cultural resources collected

during the grading monitoring program and from any previous archaeological

studies or excavations on the project site to the appropriate Tribe for proper

treatment and disposition per the Cultural Resource Treatment and Monitoring

Agreement referenced in MM-CR-3. All cultural materials that are deemed by

the Tribe to be associated with burial and/or funerary goods will be repatriated

to the Most Likely Descendant as determined by the Native American Heritage

Commission per California Public Resources Code Section 5097.98.

In the event that curation of cultural resources is required, curation shall be

conducted by an approved facility and the curation shall be guided by California

State Historic Resource Commissions Guidelines for the Curation of

Archaeological Collections. The City of San Marcos shall provide the developer

final curation language and guidance on the project grading plans prior to

issuance of the grading permit, if applicable, during project construction.





Coroner has made the necessary findings as to origin. Further, pursuant to

California Public Resources Code Section 5097.98(b) remains shall be left in

place and free from disturbance until a final decision as to the treatment and

disposition has been made. Suspected Native American remains shall be

examined in the field and kept in a secure location at the site If the San Diego

County Coroner determines the remains to be Native American, the Native

American Heritage Commission (NAHC) must be contacted within 24 hours. The

NAHC must them immediately notify the “most likely descendant(s)” of

receiving notification of the discovery. The most likely descendants(s) shall

then make recommendations within 48 hours, and engage in consultation

concerning treatment of remains as provided in Public Resources Code

5097.98, .3.




assess the significance of such resources and shall meet and confer regarding

the mitigation for such resources. Pursuant to California Public Resources Code

Section 21083.2(b) avoidance is the preferred method of preservation for

archaeological resources. If the Developer, the project archaeologist and the

Tribe cannot agree on the significance of mitigation for such resources, these

issues will be presented to the Planning Director for decision. The Planning




Director shall make a determination based upon the provisions of the California

Environmental Quality Act with respect to archaeological resources and shall

take into account the religious beliefs, customs, and practices of the Tribe.

Notwithstanding any other rights available under law, the decision of the

Planning Director shall be appealable to the Planning Commission and/or City

Council.

5-3 Mitigation measure MM-CR-2 was revised to reflect this comment. The measure concludes by

stating “Any newly discovered cultural resource deposits shall be subject to cultural resources

evaluation, which shall include archaeological documentation, analysis and report generation.“

5-4 The SDCAS did not have any comments on mitigation measure MM-CR-3. This comment does

not raise any environmental issues; therefore no additional response is provided.

5-5 The City has coordinated closely with local Tribes to generated mitigation language that was

acceptable to their group. The resulting mitigation measures, MM-CR-1 through MM-CR-8

reflect the requests of the Tribes. Mitigation measures CR-5 has been revised to note that In the

event that curation of cultural resources is required, curation shall be conducted by an

approved facility and the curation shall be guided by California State Historic Resource

Commissions Guidelines for the Curation of Archaeological Collections. The City of San Marcos

shall provide the developer final curation language and guidance on the project grading plans

prior to issuance of the grading permit, if applicable, during project construction.

5-6 This comment provides closing remarks and does not raise any issues on the environmental

document, therefore no additional response is provided.




6-1




6-1

Cont.

6-2




6-3

6-2

Cont.




6-5

6-3

Cont.

6-4




6-6

6-7

6-5

Cont.







Letter 6

San Luis Rey Band of Mission Indians

6-1 This comment provides opening remarks and indicates that requests that revisions to the

cultural resource mitigation measures be made in the Final CEQA document. The specific

requests are detailed in subsequent comments. Please see responses, below.

6-2 The City recognizes that the Native American monitor and the archeological monitor will have

join authority to divert or halt ground disturbing operations should a cultural resource be

identified. Mitigation measure MM-CR-3 addresses the participation of a Native American Tribal

monitor during project construction. Implementation of mitigation measures MM-CR-3 will be

required as a condition of project approval.

6-3 This comment addresses repatriation of cultural resources to the Tribe. Mitigation measure

MM-CR-5 addresses repatriation.

6-4 Mitigation measures MM-CR-6 addresses sacred sites. Specifically, All sacred sites, should they

be encountered within the project area, shall be avoided and preserved as the preferred

mitigation, if feasible.

6-5 This comment addresses Tribal notification in the event that cultural resources are found during

project grading. Per mitigation measure MM-CR-3, a Native American Tribal monitor will be

required for the project.

6-6 No fill will be brought onto the project site. As noted in the project description for the project,

earthwork quantities will balance on site.

6-7 This comment provides closing remarks and does not raise any additional environmental issues.

Therefore, no further response is warranted.




7-1




7-1

Cont.




Letter 7

U.S. Department of Homeland Security/FEMA

7-1 The project site is not in a FEMA mapped floodplain or floodway. In fact, the panel for the site

has not even been printed. Therefore, the comments in this letter do not apply to the project or

project site and no additional responses are warranted.

4.0 Mitigation Monitoring and Reporting Program


Final Initial Study/Mitigated Negative Declaration March 2014

4.0 MITIGATION MONITORING AND REPORTING PROGRAM

4.1 INTRODUCTION AND SUMMARY

Pursuant to Section 21081.6 of the Public Resources Code and the California Environmental Quality Act

(CEQA) Guidelines Section 15097, public agencies are required to adopt a monitoring or reporting

program to assure that mitigation measures and revisions identified in the Mitigated Negative

Declaration (MND) are implemented. As stated in Section 21081.6 of the Public Resources Code:

“… the public agency shall adopt a reporting or monitoring program for the changes

made to the project or conditions of project approval, adopted in order to mitigate or

avoid significant effects on the environment.”

Pursuant to Section 21081(a) of the Public Resources Code, findings must be adopted by the decision

makers coincidental to certification of the MND. The Mitigation Monitoring and Reporting Program

(MMRP) must be adopted when making the findings (at the time of approval of the project).

As defined in the CEQA Guidelines, Section 15097, “reporting” is suited to projects that have readily

measureable or quantitative measures or which already involve regular review. “Monitoring” is suited

to projects with complex mitigation measures, such as wetland restoration or archaeological protection,

which may exceed the expertise of the local agency to oversee, are expected to be implemented over a

period of time, or require careful implementation to assure compliance. Both reporting and monitoring

would be applicable to the proposed project.

The Initial Study/ Mitigated Negative Declaration prepared for the Heart of the City Specific Plan

Amendment (Rancho Coronado) (SCH No. 2014021007) provided an analysis of the environmental

effects resulting from construction and operation of the project.

4.2 MITIGATION MATRIX

To sufficiently track and document the status of mitigation measures, a mitigation matrix has been

prepared and includes the following components:

• Impact

• Mitigation Measure

• Action

• Timing

• Responsibility

The mitigation matrix is included in Table 4-1. Additionally, the project will be required to adhere to the

design features presented in Table 4-2.




Table 4-1. Mitigation Measures

Impact Mitigation Measure Action Timing Responsibility

BIOLOGICAL RESOURCES

The following project design

measure shall be carried

forward from the HLP

conditions to minimize

impacts to biological

resources and are identified

as mitigation measures for

the project. Implementation

of this mitigation measures

will be required as a

condition of project approval.

MM-BIO-A The clearing and grubbing of sensitive

habitats shall occur outside of the bird breeding season

(February 15 to August 31), unless a qualified biologist

demonstrates to the satisfaction of the City and the Wildlife

Agencies that all nesting is complete. The qualified biologist

would need to be federally permitted for coastal California

gnatcatcher if the habitat being cleared has potential to

support these species.

Avoid clearing or

grubbing activities during

the avian breeding

season or perform a pre-

construction survey to

ensure no nests are

present. Results of the

survey shall be submitted

to the Wildlife Agencies

and the Planning

Director.

Avoidance covers

the period of

February 15 to

August 31.

Preconstruction

surveys would be

within three days of

propose clearing

and grubbing.

Applicant, Project

Biologist












MM-BIO-B Temporary perimeter fencing shall be

installed to separate the proposed development and the fuel

management zones from any CSS areas to the preserved

under the HLP. The removal of temporary fencing is only to

occur after all clearing and construction has been

completed.

Installation of temporary

fencing

Prior to project

grading

Applicant, Project

Biologist












MM-BIO-C Lots adjacent to biological open space will

have permanent fencing and no gates between the

development and the open space; (a) landscaping will be

restricted to native and/or non-invasive plant species; and

(b) Best Management Practices (BMPs) during construction

in accordance with Nation Pollutant Discharge Elimination

Systems General Construction Permit requirements will be

implemented.

Installation of permanent

fencing between

development and open

space.

Implementation of BMPs

for water quality during

project construction.

Installation of

permanent fencing

prior to project

occupancy.

BMP

implementation is

during project

construction.

Applicant,

Contractor.
















MM-BIO-D A biological monitor will be on-site when

habitat is being cleared, and/or construction activities are

occurring within 100 feet of a Biological Open Space

Easement boundary. Permanent signs must be placed every

100 feet along the fence bordering the preserve. The signs

must be corrosion resistant, no less than three feet above

the ground surface, have minimum dimensions of 6” x 9”,

and must state the following:

Sensitive Environmental Resources

Disturbance Beyond this point is Restricted

By Easement

Information:

Contact (Name of Conservancy)

Monitoring during

construction activities

and placement of

permanent signage along

boundary of

conservation area.

Signage shall be

placed prior to

project

construction.

Monitoring shall

occur during

project

construction.

Applicant, Project

Biologist












MM-BIO-E A conservation easement shall be placed

over all on-site mitigation. Additionally, the applicant shall

insure that the biological open space is deeded to a nature

conservancy acceptable to the planning Division Director for

maintenance and monitoring purposes.

Recordation of a

conservation easement

over onsite mitigation

areas and deeding of

open space to a nature

conservancy.

Prior to issuance of

grading permit.

Owner/Applicant

and City.












MM-BIO-F Manufactured slopes will be revegetated

with appropriate native species in consultation with the

Wildlife Agencies. The landscape plan and construction

documents will be approved by the City Engineer, Planning

Director, and Fire Marshal prior to issuance of building

permits.

Revegetation of

manufactured slopes

with native species.


building permit.

Applicant, City

Engineer,

Planning Director

and Fire Marshal

and Wildlife

Agencies.
















MM-BIO-G Any lands providing mitigation/

preservation for the project shall be held in perpetuity in

accordance with a habitat management plan to be approved

by the City and the Wildlife Agencies.

Preservation of land in

perpetuity.


grading permit.

Owner/Applicant,

City and Wildlife

Agencies

Development of the project

will result in impact to

riparian habitats. This

represents a significant

impact.

MM-BIO-1A Impacts to 0.23 acre southern riparian

forest, 0.15 acre riparian woodland, 1.43 acres southern

willow scrub, 0.90 acre freshwater marsh, 0.33 acre mule fat

scrub, and 0.09 SWS/FWM habitat will be mitigated at a 3:1

ratio. Impacts to 0.85 acres disturbed wetland will be

mitigated at a 2:1 ratio. Impact to 0.02 acre streambed will

be mitigated at a 1:1 ratio as detailed in Table 7a for a total

of 8.89 acres of mitigation. Mitigation includes a

combination of onsite and offsite creation and enhancement

with 6.47 acres of creation and 0.30 acres of enhancement

occurring onsite and 1.27 acre creation mitigation credit

equivalents and 1.05 acres enhancement credits at the

North County Habitat Bank (NCHB).

Habitat creation both on

and offsite to meet the

required mitigation

amounts.

Prior to project

construction

Applicant, Project

Biologist

Impact to riparian habitats. MM-BIO-1B The preparation of a riparian restoration

plan will be required as a condition of the mitigation for

impacts to riparian vegetation communities. The plan will be

require review and approval by the City and include the

following.

• All final specifications and topographic-based

grading, planting, and irrigation plans (0.5-foot

contours and typical cross-sections) for the

creation/restoration sites. All wetland mitigation

areas shall be graded to the same elevation as

The preparation of a

riparian restoration plan


condition of the

mitigation for impacts to

riparian vegetation

communities.

Restoration plan

shall be prepared

and approved prior

to impact to

riparian habitats.

Applicant, Project

Biologist, City of

San Marcos





adjacent existing jurisdictional wetlands areas,

and/or to within 1 foot of the groundwater table,

and shall be left in a rough grade state with micro

topographic relief (including channels for wetlands)

that mimics natural topography, as directed by the

City and Resource Agencies. All plantings shall be

installed in a way that mimics natural plant

distribution, and not in rows;

• Planting palettes (plant species, size, and

number/acre) and seed mix (plant species and

pounds/acre). Unless otherwise approved by the

City and Resource Agencies, only locally native

species (no cultivars) obtained from as close to the

project area as possible shall be used. The source

and proof of local nativeness of all plant material

and seed shall be provided;

• Container plant survival shall be 80 percent of the

initial plantings for the first year;

• A final implementation schedule that indicates

when all riparian/wetland impacts, as well as

riparian/wetland creation/restoration grading,

planting, and irrigation, will begin and end.

Necessary site preparation and planting shall be

completed during the concurrent or next planting

season (i.e., late fall to early spring). Any temporal

loss of habitat caused by delays in riparian/wetland

habitat creation/restoration shall be offset through

like habitat creation/restoration at a 0.5:1 ratio for

every 6 months of delay (i.e., 1:1 for 12 months

delay, 1.5:1 for 18 months delay, etc.). In the event

that the project applicant is wholly or partly

prevented from performing obligations under the

final plans (causing temporal losses due to delays)

because of unforeseeable circumstances or causes

beyond the reasonable control, and without the

fault of negligence of the project applicant,





including but not limited to natural disasters (e.g.,

earthquakes, etc.), labor disputes, sudden actions

of the elements (e.g., further landslide activity), or

actions or inaction by federal or state agencies, or

other governments, the project applicant will be

excused by such unforeseeable cause(s);

• Five years of success criteria for wetland/riparian

creation/restoration areas, including separate

percent cover criteria for herbaceous understory,

shrub midstory, and tree overstory, and a total

percent absolute cover for all 3 layers at the end of

5 years; evidence of natural recruitment of multiple

species for all habitat types; 0 percent coverage for

Cal-IPC’s “Invasive Plant Inventory” species, and no

more than 10 percent coverage for other

exotic/weed species;

• A minimum of 5 years of maintenance and

monitoring of riparian/wetland creation/restoration

areas, unless success criteria are met earlier and all

artificial water supply has been off for at least 2

years

• A qualitative and quantitative vegetation

monitoring plan with a map of proposed sampling

locations. Photo points shall be used for qualitative

monitoring and stratified-random sampling shall be

used for all quantitative monitoring;

• Contingency measures in the event of

creation/restoration failure;

• ·Annual mitigation maintenance and monitoring

reports shall be submitted to the City and Resource

Agencies no later than December 1 of each year;

• A wetland delineation shall be done to confirm that

USACE and CDFW jurisdictional wetlands have been

successfully created/restored prior to final approval

of creation/restoration sites.





Potential for impact to

species protected under the

Migratory Bird Treaty Act due

to project construction.

MM-BIO-2 Potential direct impacts to bird species

covered under the MBTA will be mitigated by restricting

brushing and grading to outside of the breeding season of

most bird species (general breeding season is February 15 to

August 31). Grubbing, grading, or clearing during the

breeding season of MBTA covered species could occur if it is

determined via a pre-construction survey that no nesting

birds (or birds displaying breeding or nesting behavior) are

present immediately prior to grubbing, grading, or clearing

and will require approval of the City that no breeding or

nesting avian species are present in the vicinity of the

grubbing, grading, or clearing. The City shall be notified of

any sensitive bird species identified during the pre-

construction surveys.

Avoidance of grubbing,

grading or clearing

during breeding season

or conduct a pre-


ensure there are no

breeding birds on site.

Avoidance of

grubbing, grading

or clearing between

the period of

February 15 to

August 31, or

conduct a pre-

construction survey

prior to

construction.

Applicant, Project

Biologist, City of

San Marcos

Potential for edge effects

from human activity adjacent

to biological open space lots.

MM-BIO-3 To reduce edge effects, on-site human

activity, and potential impacts related to the introduction of

exotic and domestic animals, the biological open space lots

shall be actively managed and monitored. The required

habitat management plan (as detailed in MM-BIO-1B) shall

ensure that access be restricted to developed areas.

Permanent fencing shall be provided for all backyards

abutting proposed project open space. In addition,

preserved habitat shall be posted with signs precluding

access due to habitat sensitivity and prohibiting dumping.

Residents shall be educated in access restrictions, control of

domestic animals, prevention of irrigation runoff, and

sensitivity of habitats on site.

Installation of permanent

fencing to restrict access

to developed areas.

Permanent fencing

prior to project

occupancy.

Residents shall be

notified of

restrictions upon

purchase of home.

Applicant, Project

Biologist

Potential for impact to

California gnatcatcher and

nesting raptors if grading or

clearing occurs during the

nesting season.

MM-BIO-4 If project grading (other than clearing and

grubbing of sensitive habitats) is necessary and adjacent to

preserved on-site habitat during the bird breeding season

(February 15 to August 31), a qualified biologist shall

conduct pre-construction surveys in the adjacent habitat for

the coastal California gnatcatcher\ and nesting raptors. The

survey shall begin not more than three days prior to the

beginning of grading activities. The Wildlife Agencies shall

Avoidance of grubbing,

grading or clearing

during breeding season

or conduct a pre-


ensure there are no

breeding birds on site.

Avoidance of

grubbing, grading

or clearing between

the period of

February 15 to

August 31, or

conduct a pre-

construction survey

Applicant, Project

Biologist, City of

San Marcos





be notified if the gnatcatcher is observed nesting within 300

feet of proposed grading or if raptors are observed nesting

within 500 feet of proposed grading activities. No activities

which would result in noise levels exceeding 60 dBA hourly

Leq within this buffer shall be allowed. If grading activities

are not initiated prior to the breeding season, and any of

these species are present, and noise levels exceed this

threshold, noise barriers shall be erected to reduce noise

impacts to occupied habitat to below 60 dBA hourly Leq

and/or the activities shall be suspended. Impacts resulting

from noise for non-listed species other than raptors are not

considered significant, and mitigation is not warranted.

If birds are found on site,

noise levels shall be

curtailed to the level

noted in this mitigation

measures

prior to

construction.

Noise monitoring

during construction

if besting raptors or

CAGN are found

during the

preconstruction

surveys.

CULTURAL RESOURCES

Potential to encounter

unidentified cultural

resources during project

grading activities.

MM-CR-1 An archeological monitor and a Luiseño

Native American monitor shall be present during all earth

moving and grading activities to assure that any potential

cultural resources, including tribal, found during project

grading be protected.

Monitoring of

earthmoving and grading

activities.

During grading and

earthmoving

activity

Applicant,

Archaeological

Monitor, and

Tribal Monitor

MM CR-2 Prior to beginning project construction,

the Project Applicant shall retain a San Diego County

qualified archaeological monitor to monitor all ground-

disturbing activities in an effort to identify any unknown

archaeological resources. Any newly discovered cultural

resource deposits shall be subject to cultural resources

evaluation, which shall include archaeological

documentation, analysis and report generation.

Retention of an

archaeological monitor

to monitor ground

disturbing activities.

At least 30 days

prior to grading the

applicant shall

execute a Cultural

Resources and

Treatment

agreement with the

Applicant

MM-CR-3 At least 30 days prior to beginning project

construction, the Project Applicant shall enter into a Cultural

Resource Treatment and Monitoring Agreement (also known

as a pre-excavation agreement) with a Luiseño Tribe. The

Agreement shall address the treatment of known cultural

resources, the designation, responsibilities, and participation

of professional Native American Tribal monitors during

grading, excavation and ground disturbing activities; project

Development of a

Cultural Resources

Treatment and

Monitoring Agreement.

At least 30 days

prior to grading the

applicant shall

execute a Cultural

Resources and

Treatment

agreement with the

Applicant and

Rincon Band





grading and development scheduling; terms of

compensation for the monitors; and treatment and final

disposition of any cultural resources, sacred sites, and


MM-CR-4 Prior to beginning project construction,

the Project Archaeologist shall file a pre-grading report with

the City to document the proposed methodology for grading

activity observation, which will be determined in

consultation with the Luiseño Tribe referenced in MM-CR-3. .

Said methodology shall include the requirement for a

qualified archaeological monitor to be present and to have

the authority to stop and redirect grading activities. In

accordance with the agreement required in MM-CR-3, the

archaeological monitor’s authority to stop and redirect

grading will be exercised in consultation with the Luiseño

Native American monitor in order to evaluate the

significance of any archaeological resources discovered on

the property. Tribal and archaeological monitors shall be

allowed to monitor all grading, excavation, and

groundbreaking activities, and shall also have the authority

to stop and redirect grading activities.

Filing of a pre-grading

report with the City.

Prior to project

construction.

Applicant

MM-CR-5 The landowner shall relinquish ownership

of all cultural resources collected during the grading

monitoring program and from any previous archaeological

studies or excavations on the project site to the appropriate

Tribe for proper treatment and disposition per the Cultural

Resource Treatment and Monitoring Agreement referenced

in MM-CR-3. All cultural materials that are deemed by the

Tribe to be associated with burial and/or funerary goods will

be repatriated to the Most Likely Descendant as determined

by the Native American Heritage Commission per California

Public Resources Code Section 5097.98.

In the event that curation of cultural resources is required,

curation shall be conducted by an approved facility and the

Landowner shall

relinquish any cultural

resources found on the

site to the appropriate

Tribe.

At the time

resources are

found.

Applicant





curation shall be guided by California State Historic Resource

Commissions Guidelines for the Curation of Archaeological

Collections. The City of San Marcos shall provide the

developer final curation language and guidance on the

project grading plans prior to issuance of the grading permit,

if applicable, during project construction.

MM-CR-6 All sacred sites, should they be

encountered within the project area, shall be avoided and

preserved as the preferred mitigation, if feasible.

Avoidance and

preservation (if feasible)

of sacred sites

At the time of

encounter

Applicant

MM-CR-7 If human remains are encountered,

California Health and Safety Code Section 7050.5 states that

no further disturbance shall occur until the San Diego

County Coroner has made the necessary findings as to

origin. Further, pursuant to California Public Resources Code

Section 5097.98(b) remains shall be left in place and free

from disturbance until a final decision as to the treatment

and disposition has been made. Suspected Native American

remains shall be examined in the field and kept in a secure

location at the site If the San Diego County Coroner

determines the remains to be Native American, the Native

American Heritage Commission (NAHC) must be contacted

within 24 hours. The NAHC must them immediately notify

the “most likely descendant(s)” of receiving notification of

the discovery. The most likely descendants(s) shall then

make recommendations within 48 hours, and engage in

consultation concerning treatment of remains as provided in

Public Resources Code 5097.98,

Halting of construction

and contact NAHC.

At the time human

remains are

encountered

Applicant

MM-CR-8 If inadvertent discoveries of subsurface

archaeological/cultural resources are discovered during

grading, the Developer, the project archaeologist, and the

Luiseño Tribe under agreement with the landowner

described in MM-CR-3 shall assess the significance of such

resources and shall meet and confer regarding the

mitigation for such resources. Pursuant to California Public

Resources Code Section 21083.2(b) avoidance is the

Halt construction and

assess significance or

resources.

At the time

inadvertent

discoveries are

encountered

Applicant





preferred method of preservation for archaeological

resources. If the Developer, the project archaeologist and

the Tribe cannot agree on the significance of mitigation for

such resources, these issues will be presented to the

Planning Director for decision. The Planning Director shall

make a determination based upon the provisions of the

California Environmental Quality Act with respect to

archaeological resources and shall take into account the

religious beliefs, customs, and practices of the Tribe.

Notwithstanding any other rights available under law, the

decision of the Planning Director shall be appealable to the

Planning Commission and/or City Council

HAZARDS/HAZARDOUS MATERIALS

Potential for impact due to

naturally-occurring arsenic on

the project site.

MM-HAZ-1

Prior to grading activities, the project applicant shall prepare

and implement a soils management plan that addresses

handling of soils containing naturally-occurring arsenic

during grading. The management plan shall be submitted to

the City Engineer for review and approval prior to the

issuance of a grading permit.

Prepare a Soils

Management Plan and

submit to the City.

Prior to grading Applicant and

City.

The project proposes

development adjacent to

natural areas which will be

preserved as open space. This

creates and areas where

development will be adjacent

to wildland areas that have a

high fire risk. This represents

a significant impact.

MM-HAZ-2 Prior to issuance of building permits, a fire

protection plan shall be prepared for the project and

submitted to the Planning Director and Fire Marshal for

review and approval. The fire protection plan shall include

fire fuel clearing and fire fuel management zones to provide

a minimum 150-foot buffer between proposed structures

and natural habitat. The fire protection plan shall identify

the responsible parties for the ongoing fire fuel maintenance

and the mechanism to ensure compliance with fire clearing

requirements. Implementation of the fire protection plan

shall be required prior project occupancy.

Preparation of fire

protection plan.


building permit

Applicant and

City (Planning

Director and Fire

Marshal)





NOISE

Onsite noise impacts due to

traffic for select homes.

MM-N-1 Sound barriers ranging from five to ten

feet shall be constructed to reduce future onsite noise levels

to be consistent with the Noise Element of the San Marcos

General Plan (60 dBA CNEL for single family and 65 dBA for

multifamily). Locations and heights of the proposed barriers

are presented in Figure 7, Noise Mitigation Measures.

Barriers could include berms, wall, glass or a combination of

these to meet the required noise attenuation.

Construction of noise

attenuation features

Prior to occupancy

of homes along the

west side of Las

Posas Road within

the project area.

Applicant

Potential for elevated interior

sound levels for select

homes.

MM-N-2 A final noise assessment shall be prepared

prior to the issuance of the first building permit. This final

report would identify the interior noise requirements based

upon architectural and building plans to meet the City’s

established interior noise limit of 45 dBA CNEL.

Conduct final noise

assessment and mitigate

noise conditions to

acceptable levels if an

exceedance is identified


first building

permit.

Applicant

Potential for elevated

exterior noise levels on the

non-residential mixed use

portion of the project site.

MM-N-3 If outdoor usable areas are proposed in

the non-residential mixed use areas of the project, the

design shall consider shielding form the buildings, increased

setbacks from the roadways or conduct a site specific noise

study to determine compliance. An interior noise

assessment is required to mitigate the exterior noise levels

to an interior level of 50 dBA CNEL. This report should be

conducted prior to the issuance of building permits and

would finalize the noise requirements based upon actual

building design specifications.

Conduct final noise

assessment and mitigate

noise conditions to

acceptable levels if an

exceedance is identified


first building

permit.

Applicant

Potential for noise impacts

during rock crushing.

MM-N-4 If rock crushing is proposed, upon starting

of crushing operations, noise measurements of the rock

crushing facility shall be required to ensure compliance with

the City’s thresholds. If noise levels are found to be above

the established thresholds of 60 dBA at any existing single

family residential use, 65 dBA for any multifamily use or 70

dBA at a commercial use then additional mitigation in the

form of berms or temporary walls will need to be

incorporated into the rock crusher design to reduce the

noise levels to below the City’s thresholds.

Take noise

measurements if two

crushers will be operated

simultaneously. If noise

levels exceed thresholds,

implement noise

reduction measure to

meet noise standards.

During rock

crushing phase.

Applicant





TRAFFIC AND CIRCULATION

The addition of project-

related traffic results in a

significant impact at the

intersection of Twin Oaks

Valley Road / SR-78

Eastbound Ramps Grand

Avenue/ SR-78 EB Ramps –

Via Vera Cruz in the Horizon

Year 2030 Peak Hour

Intersection Condition. This


impact.

MM-TR-1 The project applicant shall make a fair

share contribution towards the following improvements at

the Twin Oaks Valley Road/SR-78 Eastbound Ramps:

• Construct an additional dedicated right-turn lane at

eastbound (off-ramp) approach of intersection.

• Restripe eastbound approach to include one left-

turn lane, one shared left-turn/through/right-turn

lane, and two right-turn lanes.

Payment of a fair share

contribution for future

improvements at this

intersection.


building permits.

Applicant

The addition of project-

related traffic results in a

significant impact at the

intersection of Twin Oaks

Valley Road/Discover Street-

Barham Drive in the Horizon

Year 2030 Peak Hour

Intersection Condition. This


impact.

MM-TR-2 The project applicant shall make a fair

share contribution towards the widening of the northbound

approach of the Twin Oaks Valley Road/Discover Street-

Barham Drive intersection to construct a dedicated right-

turn lane.

Payment of a fair share

contribution for future

improvements at the

northbound approach of

the Twin Oaks Valley

Road/Discover Street-

Barham Drive

intersection


building permits.

Applicant




Table 4-2. Design Considerations for the Project

Air Quality

• The project shall implement dust control measures. These measures include watering of active grading

sites and unpaved roads a minimum of twice daily, replacement of ground cover as quickly as possible,

reducing speeds on unpaved roads/surfaces to 15 miles per hour or less, and reducing dust during

unloading and loading operations.

• Low-VOC coatings shall be used for all buildings, as required under SDAPCD Rule 67.0.

Biological Resources

• No invasive plant species shall be in the landscaping plans, and no species on the Cal-IPC “Invasive Plant

Inventory” list shall be included in the erosion control plan.

• All exterior lighting adjacent to preserved habitat including street lighting for Street A shall be limited to

low pressure sodium sources of the lowest illumination allowed for human safety, selectively placed,

shielded, and directed away from preserved habitat to the maximum extent practicable.

• Inspection of all plant material for Argentine ants prior to use on the site.

• The monitoring biologist shall periodically monitor adjacent habitats for excessive amounts of dust, and

recommend remedial measures to address dust control if necessary.

Geology/Soils

• The project shall implement Best Management Practices (BMPs) to minimize sedimentation or other soil

impacts during project construction. BMPs could includes some or all of these strategies: erosion bale,

silt fencing, storm drain inlet protection, outlet protection, stabilized construction entrance, brush

barrier, sandbag barrier, waste disposal and proper siting of equipment fueling.

Noise – Grading/Construction

• All equipment construction equipment shall be properly fitted with mufflers.

• All equipment staging and maintenance shall be conducted as far away from existing residences as

possible.

• All construction equipment staging and maintenance should be conducted as far away for the existing

residence as possible.

• Haul truck speed limit of 15 miles per hour shall be posted along the on-site haul route and include

signage limiting the use of engine “jake” brakes.

Noise – Blasting

• The general contractor or property owner/developer shall give reasonable notice in writing at the time

of issuance of a building permit, grading permit or encroachment license to all residences or businesses

within 600 feet of any potential blast location. The notice shall be in a form approved by the Building

Director. Any resident or business receiving such notice may request of the Building Director that a

notice of impending blasting be given by the blaster at the time of the 12 hour advance notice given to

the Building Director. The general contractor or property owner/developer shall make all reasonable

efforts to contact any and all parties requesting the second notice.

• The blaster shall file a written certification with the Building Director certifying that the general notice

required by Section 17.60.060(b) has been given. The certificate shall include addresses and date(s) of

notification. A copy shall be retained on file at the Building Division.

• Inspections of all structures within 300 feet of the blast site shall be made before blasting operations.

The persons inspecting shall obtain the permission of the building owner to conduct an inspection. The

inspections shall be done by a registered structural engineer employed by the blaster or project




contractor. The inspection shall be only for the purpose of determining the existence of any visible or

reasonably recognizable pre-existing defects or damages in any structure. Inspection refusal shall be at

the discretion of the property owner.

• Blasting shall only be permitted between the hours of 9:00 a.m. and 4:00 p.m. during any weekday,

Monday through Friday, exclusive of City recognized holidays unless special circumstances warrant

another time or day and special approval is granted by the Building Director and Fire Chief.

Public Services – Fire

• Roadways serving the project shall have a minimum improved paved width of 24 feet with an additional

8 feet to each side for parking. Any deviations from this or any other roadway features such as cul-de-

sacs and gates must meet the design criteria of the San Marcos Fire Department.

• Any automatic gates are required to have a Knox rapid entry system and emergency vehicle strobe

detector.

• Fire hydrants with an adequate water supply must be installed at locations approved by the San Marcos

Fire Department. Hydrant spacing shall be 300 feet apart.

• Residential structures shall be fire sprinklered per California Building Code 2010 edition and city

ordinance.

• Homes and mixed use buildings will be required to be designed using state fire marshal standards for

fire resistive construction features using the California Building Code 2013 edition Chapter 7, design to

be reviewed by City Building Department.

• A 150-foot wildland fuel modification is required from all sides of all structures.

Utilities and Service Systems

• Upsize 2,700 feet of existing 8-inch wastewater collection pipe in Craven Road. This segment is located

between Santa Barbara Drive and a point approximately 575 feet south of Discovery Street. The

improvement includes 700 feet of 10-inch pipeline and 2,000 feet of 12-inch pipeline.

• Installation of a new 14-inch diameter water main loop from the intersection of Twin Oaks Valley Road

and South Village Drive to the existing 14-inch water main, approximately 1,100 feet north of South Lake

Pump Station.

• Payment of Water Capital Facility Fees per Vallecitos Water District Ordinance No. 175.

• Payment of Wastewater Capital Facility Fees per Vallecitos Water District Ordinance No. 176.

• Payment of Wastewater Density Impact Fees per Vallecitos Water District Ordinance No. 177.

Water Quality

During construction, measures would be implemented as part of the project to control erosion, sedimentation,

and pollution that could impact water resources on and off site. Prior to the commencement of grading, a Notice

of Intent must be filed with the Regional Water Quality Board for a National Pollutant Discharge Elimination

System (NPDES) General Construction Storm Water Permit. Specific permit requirements include

implementation of an approved Storm Water Pollution Prevention Plan, which requires best management

practices for erosion and sediment control related to construction activities. Standard measures that may apply

to the proposed project include:

• Surface drainage will be designed to collect and move runoff into adequately sized drainage structures

before being discharged into natural stream channels.

• Erosion control measures associated with the project will include techniques for both long- and short-

term erosion hazards. These include such measures as the short-term use of gravel bags, matting,

mulches, berms, hay bales, or similar devices along all pertinent graded areas to minimize sediment

transport.

• Native vegetation will be preserved whenever feasible, and all disturbed areas will be stabilized as soon

as possible after completion of grading.




• Use of energy dissipating structures (e.g., detention ponds, riprap, or drop structures) will be used at

storm drain outlets, drainage crossings, and/or downstream of all culverts, pipe outlets, and brow

ditches to reduce velocity and prevent erosion.

• A maintenance plan for temporary erosion control facilities will be established. This typically involves

inspection, cleaning, and repair operations being conducted after runoff-producing rainfall.

• Removal and disposal of ground water (if any) encountered during construction activities will be

coordinated with the RWQCB to ensure proper disposal methods and locations under a General

Dewatering Permit if required. This may involve specific measures such as removing excess sediment

(through the use of desilting basins, etc.) and limiting discharge velocity.

• Specified fueling and maintenance procedures will be designated to preclude the discharge of hazardous

materials used during construction (e.g., fuels, lubricants, and solvents). Such designations will include

specific measures to preclude spill including proper handling and disposal techniques.

Per the project’s Water Quality Improvement Plan, the following Source Control BMPs are proposed:

• Mark all inlets with the words “No Dumping! Flows to Bay” or similar language.

• Landscaping is designed to minimize irrigation and runoff and to minimize the use of fertilizers and

pesticides that can contribute to stormwater pollution

• Landscaping in the bio-retention areas shall use California drought tolerant native grasses

• Plaza, sidewalks and parking lots shall be swept regularly to prevent the accumulation of litter and

debris.

The project is required to comply with the latest NPDES permit (Order No. R9-2013-0001) and latest City of San

Marcos Storm Water Standards Manual guidelines. The WQIP shall be approved by the City prior to issuance of

any grading permit and shall address Low Impact Development standards and hydromodification.

Heart of the City Specific Plan Amendment (Rancho Coronado) i City of San Marcos

Draft Initial Study/Mitigated Negative Declaration March 2014

TABLE OF CONTENTS

I. INTRODUCTION ..................................................................................................................... 1

II. PROJECT DESCRIPTION ........................................................................................................... 4

III. ENVIRONMENTAL CHECKLIST ............................................................................................... 12

A. BACKGROUND ................................................................................................................... 14

B. ENVIRONMENTAL FACTORS POTENTIALLY AFFECTED ...................................................... 15

C. DETERMINATION .............................................................................................................. 15

IV. ENVIRONMENTAL ANALYSIS ................................................................................................. 24

I. AESTHETICS ....................................................................................................................... 24

II. AGRICULTURE AND FOREST RESOURCES .......................................................................... 26

III. AIR QUALITY ...................................................................................................................... 27

IV. BIOLOGICAL RESOURCES ................................................................................................... 38

V. CULTURAL RESOURCES ..................................................................................................... 50

VI. GEOLOGY AND SOILS ......................................................................................................... 54

VII. GREENHOUSE GAS EMISSIONS .......................................................................................... 56

VIII. HAZARDS AND HAZARDOUS MATERIALS .......................................................................... 61

IX. HYDROLOGY AND WATER QUALITY .................................................................................. 65

XI. MINERAL RESOURCES ....................................................................................................... 65

XII. NOISE ................................................................................................................................ 74

XIII. POPULATION AND HOUSING ............................................................................................ 90

XIV. PUBLIC SERVICES ............................................................................................................... 91

XV. RECREATION...................................................................................................................... 93

XVI. TRANSPORTATION/TRAFFIC.............................................................................................. 94

XVII. UTILITIES AND SERVICE SYSTEMS .................................................................................... 123

V MANDATORY FINDINGS OF SIGNIFICANCE .......................................................................... 130

VI. PERSONS AND ORGANIZATIONS CONSULTED ...................................................................... 133

VII. REFERENCES ...................................................................................................................... 134

VIII. MITIGATED NEGATIVE DECLARATION ................................................................................. 136

IX. FINDINGS ........................................................................................................................... 137

Heart of the City Specific Plan Amendment (Rancho Coronado) ii City of San Marcos


LIST OF APPENDICES (Appendices included on CD in back of document)

Appendix A.1 Tentative Map

Appendix A.2 Amended Heart of the City Specific Plan

Appendix A.3 Draft Rancho Coronado Residential Design Guidelines

Appendix B Air Quality Report

Appendix C Biological Technical Report

Appendix D Cultural Resources Report

Appendix E Geotechnical Report

Appendix F Global Climate Change Report

Appendix G Draft Phase I Environmental Site Assessment

Appendix H Additional Soil Characterization Report

Appendix I Water Quality Improvement Plans

Appendix J Breach Study and Inundation Map

Appendix K Noise Report

Appendix L Police, Fire and School Letters

Appendix M Traffic Analysis

Appendix N Water and Sewer Study

Appendix O Least Bell’s Vireo Survey Report

LIST OF FIGURES

Figure 1. Project Location and Vicinity .............................................................................................. 5

Figure 2. Proposed Project ................................................................................................................. 6

Figure 3. Rancho Coronado Residential Development Areas ............................................................ 7

Figure 4. Proposed Spillway Channel Cross Section .......................................................................... 8

Figure 5. Ambient Noise Monitoring Locations ............................................................................... 76

Figure 6. Modeled Receptor Locations ............................................................................................ 77

Figure 7. Noise Mitigation Measures – Barrier Height and Locations ............................................. 79

Figure 8. Rock Crusher Noise Contour ............................................................................................. 89

Heart of the City Specific Plan Amendment (Rancho Coronado) iii City of San Marcos


LIST OF TABLES

Table 1. Rancho Coronado Residential Development Standards ..................................................... 7

Table 2. Design Considerations for the Project .............................................................................. 10

Table 3. Attainment Status of Criteria Pollutants in San Diego Air Basin ....................................... 28

Table 4. Screening-Level Criteria for Air Quality Impacts ............................................................... 29

Table 5a. Construction Emissions – Proposed Project ..................................................................... 31

Table 5b. Operational Emissions – Proposed Project ....................................................................... 34

Table 6. CO Hot Spot Evaluation – Predicted CO Concentrations, ppm ......................................... 36

Table 7a. Mitigation Requirements for Rancho Coronado (acres) ................................................... 41

Table 7b. Summary of Impact to Vegetation Communities ............................................................. 46

Table 8. USACE and CDFW Jurisdictional Impacts .......................................................................... 49

Table 9a. Summary of Estimated Operational GHG Emission – Business as Usual Scenario ........... 58

Table 9b. Summary of Estimated Operational GHG Emission – With GHG Reduction

Measures Scenario ............................................................................................................ 59

Table 10. Measured Ambient Noise Levels ...................................................................................... 75

Table 11. Future Traffic Parameters ................................................................................................. 75

Table 12. Future Exterior Noise Levels ............................................................................................. 78

Table 13. Vibration Levels from Construction Activities (Residential Receptors) ............................ 81

Table 14. Existing Roadway Noise Levels ......................................................................................... 83

Table 15. Existing + Project Roadway Noise Levels .......................................................................... 84

Table 16. Existing vs. Existing + Project Roadway Noise Levels ........................................................ 84

Table 17. Existing + Project + 2030 Cumulative Roadway Noise Levels ........................................... 85

Table 18. Existing vs. Existing + Project + 2030 Cumulative Roadway Noise Levels ........................ 86

Table 19. Construction Noise Levels ................................................................................................. 88

Table 20. Rock Crushing Noise Levels ............................................................................................... 89

Table 21. Existing Peak Hour Intersection Conditions ...................................................................... 95

Table 22. Existing Daily Roadway Segment Conditions .................................................................... 95

Table 23. Proposed Project Trip Generation .................................................................................... 96

Table 24. Existing Plus Project Peak Hour Intersection Conditions .................................................. 97

Table 25. Existing Plus Project Daily Roadway Segment Conditions ................................................ 98

Table 26. Year 2016 Cumulative Peak Hour Intersection Conditions - Without and With

Project ............................................................................................................................... 99

Table 27. Year 2016 Cumulative Daily Roadway Segment Conditions - Without and With

Project ............................................................................................................................. 100

Table 28. Year 2020 Cumulative Peak Hour Intersection Conditions Without and With

Project ............................................................................................................................. 102

Table 29. Year 2020 Cumulative Daily Roadway Segment Conditions - Without and With

Project ............................................................................................................................. 103

Table 30. Horizon Year 2030 Peak Hour Intersection Conditions - Without and With

Project ............................................................................................................................. 104

Table 31. Horizon Year 2030 Daily Roadway Segment Conditions - Without and With

Project ............................................................................................................................. 106

Table 32. Caltrans ILV Analysis ....................................................................................................... 108

Table 33. Peak Hour Freeway Segment Analysis Existing / Existing Plus Project Conditions ......... 108

Table 34. Peak Hour Freeway Segment Analysis Year 2016 Cumulative Conditions ..................... 110

Table 35. Peak Hour Freeway Segment Analysis Year 2020 Cumulative Conditions ..................... 112

Table 36. Peak Hour Freeway Segment Analysis Horizon Year 2030 Conditions ........................... 113

Heart of the City Specific Plan Amendment (Rancho Coronado) iv City of San Marcos


LIST OF TABLES (Continued)

Table 37. Peak Hour Freeway Ramp Metering Analysis ................................................................. 115

Table 38. Peak Hour Intersection Queuing Analysis Twin Oaks Valley Road / SR-78 Eastbound

Ramps (Existing / Existing Plus Project Conditions) ........................................................ 117


Ramps (Year 2016 / Year 2020 Cumulative Conditions) ................................................. 118


Ramps (Horizon Year 2030 Conditions) .......................................................................... 119

Table 41. Rancho Coronado Estimated Water Demand ................................................................. 125

Table 42. Rancho Coronado Estimated Wastewater Flows ........................................................... 125

Heart of the City Specific Plan Amendment (Rancho Coronado) 1 City of San Marcos


I. INTRODUCTION

A. PURPOSE

This document is an Initial Study (IS) for preliminary evaluation of environmental impacts resulting from

implementation of the Heart of the City Specific Plan Amendment for the Rancho Coronado project. For

the purposes of this document, this proposed development as described in Section II, Project

Description, will be called the “proposed project.”

B. CALIFORNIA ENVIRONMENTAL QUALITY ACT REQUIREMENTS

As defined by Section 15063 of the State of California Environmental Quality Act (CEQA) Guidelines, an

IS is prepared to provide the Lead Agency with information to use in deciding to prepare either an

Environmental Impact Report (EIR) or a Negative Declaration (ND) as the most appropriate

environmental documentation for the proposed discretionary action. The City of San Marcos (City) is

designated the Lead Agency, in accordance with Section 15050 of the CEQA Guidelines. The Lead Agency

is the public agency with the principal responsibility for approving a project that may have significant

effects upon the environment.

Through this IS, the City has determined that although the project could have a significant effect on the

environment, mitigation has been included to bring all potential impacts to less than significant levels.

This determination was made based upon technical analysis, factual data, and other supporting

documentation. Therefore, a Mitigated Negative Declaration (MND) is being proposed. The IS/MND will

be circulated for a period of 30 days for public and agency review. Comments received on the document

will be considered by the City before it acts on the proposed project.

This IS has been prepared in conformance with CEQA of 1970, as amended (Public Resources Code,

Section 21000 et. seq.) and Section 15070 of the State Guidelines for Implementation of CEQA of 1970,

as amended (California Code of Regulations, Title 14, Chapter 3, Section 15000, et seq.).

C. INTENDED USES OF INITIAL STUDY/MITIGATED NEGATIVE DECLARATION

This IS, along with the attached MND, is an informational document intended to inform City decision-

makers, other responsible or interested agencies, and the public of potential environmental effects of

the proposed project. The environmental review process has been established to enable public agencies

to evaluate environmental consequences and to examine and implement methods of eliminating or

reducing any potentially adverse impacts.

D. CONTENTS OF DOCUMENT

This IS/MND is organized to facilitate a basic understanding of the existing setting and environmental

implications of the proposed project as follows:

I. INTRODUCTION identifies the City contact persons involved in the process, scope of

environmental review, environmental procedures, and incorporation by reference documents.



II. PROJECT DESCRIPTION describes the proposed project. A description of proposed discretionary

approvals and permits required for project implementation is also included.

III. ENVIRONMENTAL CHECKLIST FORM presents the results of the environmental evaluation for the

proposed project and those issue areas that would have a significant impact, potentially significant

impact, a less than significant impact with mitigation incorporation, or no impact.

IV. ENVIRONMENTAL ANALYSIS evaluates each response provided in the environmental checklist

form. Each response checked is discussed and supported with sufficient data and analysis. As

appropriate, each response discussion describes and identifies specific impacts anticipated with

project implementation. In this section, mitigation measures are also recommended, as appropriate,

to reduce adverse impacts to levels of “less than significant” where possible.

V. MANDATORY FINDINGS presents Mandatory Findings of Significance in accordance with Section

15065 of the CEQA Guidelines.

VI. PERSONS AND ORGANIZATIONS CONSULTED identifies those persons consulted and involved in

preparation of this IS.

VII. REFERENCES lists bibliographical materials used in preparation of this document.

VII. MITIGATED NEGATIVE DECLARATION

E. SCOPE OF ENVIRONMENTAL ANALYSIS

For evaluation of environmental impacts, each question from the Environmental Checklist Form is stated

and responses are provided according to the analysis undertaken as part of the Initial Study. All

responses take into account the whole action involved, including off-site as well as on-site, cumulative

as well as project-level, indirect as well as direct, and construction as well as operational impacts.

Project impacts and effects will be evaluated and quantified, when appropriate. To each question, there

are four possible responses, including:

1. No Impact: A “No Impact” response is adequately supported if the referenced information

sources show that the impact simply does not apply to the proposed project.

2. Less Than Significant Impact: Development associated with project implementation will have

the potential to impact the environment. These impacts, however, will be less than the levels of

thresholds that are considered significant and no additional analysis is required.

3. Less Than Significant With Mitigation Incorporated: This applies where incorporation of

mitigation measures has reduced an effect from “Potentially Significant Impact” to a “Less Than

Significant Impact.” The Lead Agency must describe the mitigation measures and explain how

the measures reduce the effect to a less than significant level.

4. Potentially Significant Impact: Future implementation will have impacts that are considered

significant and additional analysis and possibly an EIR are required to identify mitigation

measures that could reduce these impacts to less than significant levels.



F. PERMITS AND ENTITLEMENTS FOR PROJECT APPROVAL

Agency Discretionary Action

City of San Marcos • Adoption of Specific Plan (SP 13-006)

• Tentative Subdivision Map (TSM 13-004)

• Adoption of Mitigated Negative Declaration

(ND-14-001)

• Adoption of Mitigation Monitoring and

Reporting Program Project Approval

California Department of Fish and Game Section 1600 Streambed Alteration Agreement

Regional Water Quality Control Board Section 401 Water Quality Certification

U.S. Army Corps of Engineers Section 404 Permit

Additionally, the following ministerial approvals will be required for the project: Grading Permit,

Landscaping Permit, and Building Permit.



II. PROJECT DESCRIPTION

A. PROJECT LOCATION AND SETTING

The project is located within the southwestern portion of the Heart of the City Specific Plan (HOCSP).

The 248-acre project site property is bounded by Twin Oaks Valley Road on the east, the Discovery Hills

residential community on the north, and undeveloped land on the west and south in the

Barham/Discovery Hills neighborhood (Figure 1).

The project site sits within the boundaries of the former Hanson mining site. The eastern and northern

portions of the former Hanson mining site are disturbed from past aggregate mining activities and the

remainder of the site contains undeveloped native habitat. All upland habitat impacts associated with

the mining and the current residential project have been previously analyzed within the approved

Habitat Loss Permit (HLP; HLP 03-08) approved by the City on December 23, 2003 and approved by the

Wildlife Agencies on January 23, 2004. The project development is proposed in areas that are disturbed

from previous mining and cleared following the initial HLP approval.

B. PROJECT DESCRIPTION

The project proposes a Specific Plan Amendment (SPA) to the HOCSP. The project area covers 248 acres

within the HOCSP. The project would develop residential, non-residential mixed use, and active park

uses consistent with the General Plan. The project also preserves open space. Figure 2 shows the

planning areas of the HOCSP that are part of the proposed project (circled in red). The proposed

Tentative Map, Specific Plan Amendment, and Rancho Coronado Residential Design Guidelines are

included as Appendices A.1, A.2, and A.3.

Residential – The project would allow for up to 346 high-efficiency single family homes on

approximately 58 acres. Product types include front-loaded and alley-loaded single family detached, as

well as alley-loaded paired (duplex) and alley-loaded courtyard homes. Residential development is

proposed four areas (Area A, B, C and D), as detailed in Figure 3. The developments standards for each

of the residential areas are presented in Table 1.

Mixed Use (Non-Residential) – The project includes 22.24 acres of MU-4 (non residential mixed use) in

the southern portion of the project site, adjacent to Twin Oaks Valley Road. Allowable uses under this

designation include commercial, office professional, and office and business park uses. These uses may

be mixed vertically (on separate floors of a building) or horizontally (on a single site or adjacent parcel).

While specific development is not proposed within this area at this time, the environmental analysis

assume 90 percent of the MU-4 area would be developed with business park uses and the remaining 10

percent would be retail with a total of 240,000 s.f. developed on the 22.24 acres.

Park – Grading of 38.43 acres is proposed as a future active use City park. Anticipated uses include

active park uses, lighted ball fields, and associated parking.1

1 A park plan is not analyzed at this time, however, traffic generated by a future park, as well as air quality and noise associated

with the traffic, is considered in this analysis. At the time a park plan is proposed in the future, the project would be subject to

additional CEQA review.



Figure 1. Project Location and Vicinity



Figure 2. Proposed Project



Figure 3. Rancho Coronado Residential Development Areas

Table 1. Rancho Coronado Residential Development Standards

Residential Area A B C D

Configuration Front-loaded Single

Family Dwelling

Alley-loaded Single

Family Dwelling

Alley-loaded

Paired

Alley-loaded

Courtyard

Max. Dwelling Units 72 units 54 units 72 units 148 units

Minimum Lot Area(1)

3,910 SF 2,880 SF 2,440 SF 1,840 SF

Minimum Front Setback

from Sidewalk

10 feet 10 feet 10 feet 10 feet

Minimum Front Setback

from Paseo

N/A N/A 10 feet(3)

7.5 feet(4)

Minimum Side Setback

from Sidewalks


Minimum Side Setback

from Property Line


Minimum Front Garage

Setback from Sidewalk

16 feet/18 feet(2)

N/A N/A N/A

Minimum Rear Setback

from Property Line

16 feet/18 feet(2)

N/A N/A N/A

Minimum Rear Setback

from Back of Alley Curb


Height Limit 35 feet 35 feet 35 feet 35 feet

Notes:

(1) The Lot Area is measured from back of sidewalk and from back of private alley curb, where applicable.

(2) The front yard setback is 16 feet for the garage façade and 18 feet for the garage door

(3) Setback measured from edge of Paseo

(4) Setback measured from centerline of Paseo



Preserved Open Space – The project includes approximately 129.29 acres of preserved open space. This

includes preserved upland habitat in accordance with the approved Habitat Loss Permit, as well as

riparian areas that will be created and/or enhanced and then added to the open space easement.

Spillway Conveyance Channel – The project includes the construction of a temporary channel extension

in the southern portion of the project site to convey the spillway drainage. See Figure 4 for a cross

section of the channel and the general location within the project site. The channel would be 5 feet wide

and 5 feet deep with a 2:1 bank. The channel would be lined with half-ton rip rap on one inch of gravel

over a sand filter bank. The channel would be approximately 900 feet in length. At the time the non-

residential mixed use portion of the site is developed, a refined design to handle spillway overflow will

be developed. That final design would be subject to additional CEQA review.

Figure 4. Proposed Spillway Channel Cross Section

Roadway and Pedestrian Improvements – The proposed project includes the extension of North Village

Drive “Street B”(600 lineal feet) west of Twin Oaks Valley and Street “A” (Backbone Road, 4,400 lineal

feet) which will connect Santa Barbara Drive to the north with Twin Oaks Valley Road to the east. These

two public streets will be constructed with curb, gutter, sidewalk-trail, and landscaping. Curb to curb

widths will vary from 30 to 38 feet. The proposed private roadways range from 38 to 25 feet in paved

width, with additional width for curb, gutter, sidewalks or walking paths. A trail linkage from South Lake

Park to the project site will also be included.

Utilities – The project site is within the Vallecitos Water District (VWD) boundary and is eligible for water

service. The project site is not within VWD’s sewer district boundaries and the entire project site must

be annexed to be eligible for sewer service. This is an intra-district annexation and does not require

Local Agency Formation Commission (LAFCO) approval or process.



The project includes the necessary utility improvements to support the proposed development and

includes approximately 15,360 linear feet of water lines and 14,000 linear feet of sewer lines. The

project would connect to existing Vallecitos Water District (VWD) infrastructure for water and sewer

services.

Offsite sewer extensions within Santa Barbara Drive and Twin Oaks Valley Road would also be required.

The project will also be required to upsize approximately 2,700 feet of an existing 8-inch wastewater

collection pipe in Craven Road. This segment is located between Santa Barbara Drive and a spot

approximately 575 feet south of Discovery Street. The improvement includes 700 feet of 10-inch

pipeline and 2,000 feet of 12-inch pipeline. The project will also relocate an existing 14-inch Vallecitos

Water District water main. Finally, any existing gas, electric, or communication lines (dry utilities) will be

abandoned or relocated. New dry utility lines will be constructed to serve the project.

An existing VWD access road to South Lake Dam and the existing VWD pump station in the southern

portion of the project will be relocated within the project site in a manner that is acceptable to VWD.

Water Quality Management – The project includes a comprehensive water quality management

approach. The project proposes self-treating areas, nine bio retention basins covering over 2.5 acres and

additional best management practices (BMPs) for onsite public roads. The use of construction-related

and source control BMPs which will further minimize the addition of pollutants and debris into the

drainage system. The project includes approximately 11,198 linear feet of storm drains.

Grading – Grading for the project includes 2,608,200 cubic yards (cy) of cut and 2,853,800 cy of fill and

will balance onsite assuming a 15 to 18 percent bulking factor. This includes the 1,800 cy needed to

excavate for the spillway conveyance. No offsite export or import will be required for the project. Due to

underlying bedrock conditions blasting will be required as part of the project construction. Additionally a

rock crusher may be required for the project as well.

Project Phasing - Project phasing will include an overall grading phase commencing in 2014. The grading

phase would include blasting and rock crushing. Phase 1 construction will start in 2015 and is

anticipated to be completed by late 2016 or early 2017. Phase 1 includes Residential Areas A and B (126

dwelling units), Backbone Road (Street “A”) from Santa Barbara Drive to North Village Drive, and North

Village Drive (Street “B”) extended west to the Backbone Road.

Phase 2 construction is anticipated to start in 2017 and be complete by 2020. Phase 2 includes

construction of 220 dwelling units in Residential Areas C and D; construction of the non-residential

mixed-use portion of the project, which will include 90 percent business park and 10 percent retail;

construction of a 38.43 acre active park; construction of Backbone Road from North Village Drive to

South Village Drive; construction of South Village Drive extended west to Backbone Road; installation of

a new signal for access to the mixed use site, and construction of the access road for the mixed use site.

Finally, the project includes design considerations and will adhere to applicable regulatory

requirements, as identified in Table 2.



Table 2. Design Considerations for the Project

Air Quality

• The project shall implement dust control measures. These measures include watering of active grading

sites and unpaved roads a minimum of twice daily, replacement of ground cover as quickly as possible,

reducing speeds on unpaved roads/surfaces to 15 miles per hour or less, and reducing dust during

unloading and loading operations.

• Low-VOC coatings shall be used for all buildings, as required under SDAPCD Rule 67.0.

Biological Resources

• No invasive plant species shall be in the landscaping plans, and no species on the Cal-IPC “Invasive Plant

Inventory” list shall be included in the erosion control plan.

• All exterior lighting adjacent to preserved habitat including street lighting for Street A shall be limited to

low pressure sodium sources of the lowest illumination allowed for human safety, selectively placed,

shielded, and directed away from preserved habitat to the maximum extent practicable.

• Inspection of all plant material for Argentine ants prior to use on the site.

• The monitoring biologist shall periodically monitor adjacent habitats for excessive amounts of dust, and

recommend remedial measures to address dust control if necessary.

Geology/Soils

• The project shall implement Best Management Practices (BMPs) to minimize sedimentation or other soil

impacts during project construction. BMPs could includes some or all of these strategies: erosion bale,

silt fencing, storm drain inlet protection, outlet protection, stabilized construction entrance, brush

barrier, sandbag barrier, waste disposal and proper siting of equipment fueling.

Noise – Grading/Construction

• All equipment construction equipment shall be properly fitted with mufflers.

• All equipment staging and maintenance shall be conducted as far away from existing residences as

possible.

• All construction equipment staging and maintenance should be conducted as far away for the existing

residence as possible.

• Haul truck speed limit of 15 miles per hour shall be posted along the on-site haul route and include

signage limiting the use of engine “jake” brakes.

Noise – Blasting

• The general contractor or property owner/developer shall give reasonable notice in writing at the time

of issuance of a building permit, grading permit or encroachment license to all residences or businesses

within 600 feet of any potential blast location. The notice shall be in a form approved by the Building

Director. Any resident or business receiving such notice may request of the Building Director that a

notice of impending blasting be given by the blaster at the time of the 12 hour advance notice given to

the Building Director. The general contractor or property owner/developer shall make all reasonable

efforts to contact any and all parties requesting the second notice.

• The blaster shall file a written certification with the Building Director certifying that the general notice

required by Section 17.60.060(b) has been given. The certificate shall include addresses and date(s) of

notification. A copy shall be retained on file at the Building Division.

• Inspections of all structures within 300 feet of the blast site shall be made before blasting operations.

The persons inspecting shall obtain the permission of the building owner to conduct an inspection. The

inspections shall be done by a registered structural engineer employed by the blaster or project

contractor. The inspection shall be only for the purpose of determining the existence of any visible or

reasonably recognizable pre-existing defects or damages in any structure. Inspection refusal shall be at

the discretion of the property owner.

• Blasting shall only be permitted between the hours of 9:00 a.m. and 4:00 p.m. during any weekday,

Monday through Friday, exclusive of City recognized holidays unless special circumstances warrant

another time or day and special approval is granted by the Building Director and Fire Chief.



Public Services – Fire

• Roadways serving the project shall have a minimum improved paved width of 24 feet with an additional

8 feet to each side for parking. Any deviations from this or any other roadway features such as cul-de-

sacs and gates must meet the design criteria of the San Marcos Fire Department.

• Any automatic gates are required to have a Knox rapid entry system and emergency vehicle strobe

detector.

• Fire hydrants with an adequate water supply must be installed at locations approved by the San Marcos

Fire Department. Hydrant spacing shall be 300 feet apart.

• Residential structures shall be fire sprinklered per California Building Code 2010 edition and city

ordinance.

• Homes and mixed use buildings will be required to be designed using state fire marshal standards for

fire resistive construction features using the California Building Code 2013 edition Chapter 7, design to

be reviewed by City Building Department.


Utilities and Service Systems

• Upsize an existing 2,700 feet of existing 8-inch wastewater collection pipe in Craven Road. This segment

is located between Santa Barbara Drive and a point approximately 575 feet south of Discovery Street.

The improvement includes 700 feet of 10-inch pipeline and 2,000 feet of 12-inch pipeline.

• Installation of a new 14-inch diameter water main loop from the intersection of Twin Oaks Valley Road

and South Village Drive to the existing 14-inch water main, approximately 1,100 feet north of South Lake

Pump Station.

• Payment of Water Capital Facility Fees per Vallecitos Water District Ordinance No. 175.

• Payment of Wastewater Capital Facility Fees per Vallecitos Water District Ordinance No. 176.

• Payment of Wastewater Density Impact Fees per Vallecitos Water District Ordinance No. 177.

Water Quality

During construction, measures would be implemented as part of the project to control erosion, sedimentation,

and pollution that could impact water resources on and off site. Prior to the commencement of grading, a Notice

of Intent must be filed with the Regional Water Quality Board for a National Pollutant Discharge Elimination

System (NPDES) General Construction Storm Water Permit. Specific permit requirements include

implementation of an approved Storm Water Pollution Prevention Plan, which requires best management

practices for erosion and sediment control related to construction activities. Standard measures that may apply

to the proposed project include:

• Surface drainage will be designed to collect and move runoff into adequately sized drainage structures

before being discharged into natural stream channels.

• Erosion control measures associated with the project will include techniques for both long- and short-

term erosion hazards. These include such measures as the short-term use of gravel bags, matting,

mulches, berms, hay bales, or similar devices along all pertinent graded areas to minimize sediment

transport.

• Native vegetation will be preserved whenever feasible, and all disturbed areas will be stabilized as soon

as possible after completion of grading.

• Use of energy dissipating structures (e.g., detention ponds, riprap, or drop structures) will be used at

storm drain outlets, drainage crossings, and/or downstream of all culverts, pipe outlets, and brow

ditches to reduce velocity and prevent erosion.

• A maintenance plan for temporary erosion control facilities will be established. This typically involves

inspection, cleaning, and repair operations being conducted after runoff-producing rainfall.

• Removal and disposal of ground water (if any) encountered during construction activities will be

coordinated with the RWQCB to ensure proper disposal methods and locations under a General

Dewatering Permit if required. This may involve specific measures such as removing excess sediment

(through the use of desilting basins, etc.) and limiting discharge velocity.



• Specified fueling and maintenance procedures will be designated to preclude the discharge of

hazardous materials used during construction (e.g., fuels, lubricants, and solvents). Such designations

will include specific measures to preclude spill including proper handling and disposal techniques.

Per the project’s Water Quality Improvement Plan, the following Source Control BMPs are proposed:

• Mark all inlets with the words “No Dumping! Flows to Bay” or similar language.

• Landscaping is designed to minimize irrigation and runoff and to minimize the use of fertilizers and

pesticides that can contribute to stormwater pollution

• Landscaping in the bio-retention areas shall use California drought tolerant native grasses

• Plaza, sidewalks and parking lots shall be swept regularly to prevent the accumulation of litter and

debris.

The project is required to comply with the latest NPDES permit (Order No. R9-2013-0001) and latest City of San

Marcos Storm Water Standards Manual guidelines. The WQIP shall be approved by the City prior to issuance of

any grading permit and shall address Low Impact Development standards and hydromodification.

C. DISCRETIONARY ACTIONS

The proposed project requires the following discretionary action by the City of San Marcos:

• Amendment to the Specific Plan (SP 13-006) — An amendment of the Heart of the City Specific

Plan required to reflect the proposed project.

• Approval of Tentative Subdivision Map (TSM 13-004) — Approval of the Tentative Subdivision

map to create the individual residential lots.

D. PRIOR LAND USE PERMITTING

This section provides a background of past land use permitting on the project site.

The Hanson Operation in the Heart of the City (HOC) Specific Plan (GPA 87-09; SP 87-29) was adopted by

the City Council on January 12, 1988 and encompasses approximately 1,570 acres for the development

of California State University San Marcos (CSUSM), residential and commercial uses.

The City also approved a modification to CUP 113-86 (87 Mod), which expressly authorized mining on

835 acres within the HOC Specific Plan and required that the permittee submit a reclamation plan,

tentative subdivision map, and grading plan prior to each quarry phase. Following approval of the

modified CUP, the City entered into a Development Agreement with Hanson’s predecessors for an

approximately 960 acre area within the HOC Specific Plan identified as “Rancho Coronado” Specific Plan.

The Rancho Coronado Specific Plan encompassed the 835 acre area covered by CUP 113-86 (87 Mod)

and stated that the excavation of rock was a condition precedent to development of the Rancho

Coronado Specific Plan.

In 1992, consistent with the requirements of the prior approvals, Hanson’s predecessors submitted a

reclamation plan covering approximately 544 acres of the originally approved mining site and describing

the overall mining activities anticipated to occur in the Rancho Coronado Specific Plan. Hanson has



conducted its operations consistent with the submitted reclamation plan, however, actual mining and

reclamation has been limited to 109 acres of the approved 544-acre Reclamation area.

On June 8, 1993, the City adopted a resolution, which expressly acknowledged that mining operations

on the Project Site were in compliance with CUP 113-86 (87 Mod) including the approval of a

Reclamation Plan for the Project Site.

On August 20, 2001, the City approved a Tentative Subdivision Map and Grading Plan covering

approximately 186 acres of the Heart of the City Specific Plan. These tentative maps, which were

identified as phases “M2” and M3”, were in accordance with CUP 111-85 (87 Mod) and the 1992

Reclamation Plan acknowledged by the City in Resolution 93-4244.

On December 23, 2003 as part of the obligations under TSM 418 covering Villages l, M1, M2 and M3,

Hanson obtained approval of a Habitat Loss Permit (HLP 03-08), which permits impacts to 40.5 acres of

coastal sage scrub pursuant to the California Endangered Species Act.

On December 2, 2011, the Reclamation Plan submitted by Hanson was approved for construction and a

grading permit was issued on December 7, 2011. The grading work took place between February and

April 2012 and resulted in the establishment of stabilized 2:1 slopes or less.

E. PREVIOUS CEQA REVIEW AND ENVIRONMENTAL PERMITTING

In 1987 a Mitigated Negative Declaration (ND 276-086) was prepared in conjunction with the original

Conditional Use Permit (CUP 113-86) covering the project site. Then, in 1988 a comprehensive Final EIR

(EIR 09-87) was certified by the City Council addressing the “Heart of the City” Specific Plan and an

associated amendment to the site’s original Conditional Use Permit CUP 113-86 (87 Mod). Most

recently, in 2001, Negative Declaration (ND 01-566) was certified by the City in conjunction with its

approval of TSM 418.

A Negative Declaration for the South Lake Park Master Plan (ND 08-781), south of the project site, was

certified by the City Council on April 14, 2009, and addressed impacts associated with the South Lake

Park Master Plan including a spillway realignment.

A General Industrial Permit (GIP) was issued by the State Water Resources Control Board on April 22,

1992 for the Hanson Operation closed in 2008. However, the coverage under the GIP is still valid during

the implementation of the Reclamation Closure Plan. Prior to construction of any new project activities,

a separate General Construction Permit (GCP) will be required to ensure State Water Resources Control

Board compliance for any potential project stormwater discharge.

These environmental documents are referenced as a basis for analysis and are public documents

available for reference at the City Development Services Department.

An EIR was certified as part of the General Plan Update that changed the land uses of the subject site.



III. ENVIRONMENTAL CHECKLIST

A. BACKGROUND

1. Project Title: Heart of the City Specific Plan Amendment (Rancho Coronado)

2. Lead Agency Name and Address: City of San Marcos, 1 Civic Center Drive, San Marcos, CA

92069

3. Contact Person and Phone Number: Garth Koller, Project Planner, (760) 744-1050 ext. 3231,

[email protected]

4. Project Location: The project site sits within the boundaries of the former Hanson mining site.

The eastern and northern portions of the former Hanson mining site are disturbed from past

aggregate mining activities and the remainder of the site contains undeveloped native habitat.

The project is proposed in areas that are disturbed from previous mining.

5. Project Sponsor’s Name and Address:

Lehigh Hanson West Region

PO Box 639069

San Diego, CA 92613-9069

6. General Plan and Zoning Designations: The project site is currently zoned Specific Plan, as it falls

under the western portion of the Heart of the City Specific Plan. Under the current Specific Plan,

development within the project area could include low/medium density residential, a variety of

commercial/office professional/business park uses, open space and a park. The project will still

retain a Specific Plan designation after approval of the project.

7. Description of Project: Please see Section II for project description.

8. Surrounding land uses and setting: The project site property is bounded by Twin Oaks Valley

Road on the east, the Discovery Hills residential community on the north, and undeveloped land

on the west and south in the Barham/Discovery Hills neighborhood.

9. Other public agencies whose approval is required:

• California Department of Fish and Game (Section 1602 Permit)

• Regional Water Quality Control Board (Section 401 Certification)

• U.S .Army Corp of Engineers (Section 404 Permit)

• SWRCB (General Construction Permit, General Industrial Permit)



B. ENVIRONMENTAL FACTORS POTENTIALLY AFFECTED

The environmental factors checked below would be potentially affected by this project, involving at

least one impact that is a “Mitigated to Below a Level of Significance,” as indicated by the checklist

on the following pages. All impacts identified for the project will be mitigated to below a level of

significance.

Aesthetics Agricultural and Forest Resources Air Quality

Biological Resources Cultural Resources Geology/Soils

Greenhouse Gas Hazards/Hazardous Materials Hydrology/Water Quality

Land Use/Planning Mineral Resources Noise

Population/Housing Public Services Recreation

Transportation/Traffic

Systems Utilities/ Services Systems

Mandatory Findings of Significance

C. DETERMINATION

On the basis of this initial evaluation:

I find that the proposed project COULD NOT have a significant effect on the environment, and a

NEGATIVE DECLARATION will be prepared.

I find that although the proposed project could have a significant effect on the environment,

there will not be a significant effect in this case because revisions in the project have been made

by or agreed to by the project proponent. A MITIGATED NEGATIVE DECLARATION will be

prepared.

I find that the proposed project MAY have a significant effect on the environment, and an

ENVIRONMENTAL IMPACT REPORT is required.

I find that the proposed project MAY have a “potentially significant impact” or “potentially

significant unless mitigated” impact on the environment, but at least one effect: 1) has been

adequately analyzed in an earlier document pursuant to applicable legal standards, and 2) has

been addressed by mitigation measures based on the earlier analysis as described on attached

sheets. An ENVIRONMENTAL IMPACT REPORT is required, but it must analyze only the effects

that remain to be addressed.

I find that although the proposed project could have a significant effect on the environment,

because all potentially significant effects (a) have been analyzed adequately in an earlier EIR or

NEGATIVE DECLARATION pursuant to applicable standards, and (b) have been avoided or

mitigated pursuant to that earlier EIR or NEGATIVE DECLARATION, including revisions or

mitigation measures that are imposed upon the proposed project, nothing further is required.

Date: March 19, 2014



Issues

Potentially

Significant

Impact

Less Than

Significant

With

Mitigation

Incorporated

Less Than

Significant

Impact

No

Impact

I. AESTHETICS. Would the proposal:

a) Have a substantial adverse effect on a scenic vista? X

b) Substantially damage scenic resources, including, but

not limited to, trees, rock outcroppings, and historic

buildings within a state scenic highway?

X

c) Substantially degrade the existing visual character or

quality of the site and its surroundings? X

d) Create a new source of substantial light or glare,

which would adversely affect day or nighttime views

in the area?

X

II. AGRICULTURAL AND FOREST RESOURCES. In determining whether impacts to agricultural resources are

significant environmental effects, lead agencies may refer to the California Agricultural Land Evaluation and

Site Assessment Model (1997) prepared by the California Department of Conservation as an optional

model to use in assessing impacts on agriculture and farmland. In determining whether impacts to forest

resources, including timberland, are significant environmental effects, lead agencies may refer to

information compiled by the California Department of Forestry and Fire Protection regarding the state’s

inventory of forest land, including the Forest Legacy Assessment Project and the carbon measurement

methodology provided in Forest Protocols adopted by the California Air resources Board. Would the

project:

a) Convert Prime Farmland, Unique Farmland, or

Farmland of Statewide Importance (Farmland), as

shown on the maps prepared pursuant to the

Farmland Mapping and Monitoring Program of the

California Resources Agency, to non-agricultural use?

X

b) Conflict with existing zoning for agricultural use, or a

Williamson Act contract? X

c) Conflict with existing zoning for, or cause rezoning of,

forest land (as defined in Public Resources Code

section 12220(g)), timberland (as defined in Public

Resources Code section 4526), or timberland zoned

Timberland Production (as defined by Government

Code section 51104(g))?

X

d) Result in the loss of forest land or conversion of

forest land to non-forest use? X

e) Involve other changes in the existing environment

which, due to their location or nature, could result in

conversion of Farmland, to non-agricultural use or

conversion of forest land to non-forest use?

X

III. AIR QUALITY. Where available, the significance criteria established by the applicable air quality

management or air pollution control district may be relied upon to make the following determinations.

Would the project:

a) Conflict with or obstruct implementation of the

applicable air quality plan? X

b) Violate any air quality standard or contribute

substantially to an existing or projected air quality

violation?

X



Issues

Potentially

Significant

Impact

Less Than

Significant

With

Mitigation

Incorporated

Less Than

Significant

Impact

No

Impact

c) Result in a cumulatively considerable net increase of

any criteria pollutant for which the project region is

non-attainment under an applicable federal or state

ambient air quality standard (including releasing

emissions, which exceed quantitative thresholds for

ozone precursors)?

X

d) Expose sensitive receptors to substantial pollutant

concentrations? X

e) Create objectionable odors affecting a substantial

number of people? X

IV. BIOLOGICAL RESOURCES. Would the project:

a) Have a substantial adverse effect, either directly or

through habitat modifications, on any species

identified as a candidate, sensitive, or special status

species in local or regional plans, policies, or

regulations, or by the California Department of Fish

and Game or U.S. Fish and Wildlife Service?

X

b) Have a substantial adverse effect on any riparian

habitat or other sensitive natural community

identified in local or regional plans, policies,

regulations, or by the California Department of Fish

and Game or U.S. Fish and Wildlife Service?

X

c) Have a substantial adverse effect on federally

protected wetlands as defined by Section 404 of the

Clean Water Act (including, but not limited to, marsh,

vernal pool, coastal, etc.) through direct removal,

filling, hydrological interruption, or other means?

X

d) Interfere substantially with the movement of any

native resident or migratory fish or wildlife species or

with established native resident or migratory wildlife

corridors, or impede the use of native wildlife nursery

sites?

X

e) Conflict with any local policies or ordinances

protecting biological resources, such as a tree

preservation policy or ordinance?

X

f) Conflict with the provisions of an adopted Habitat

Conservation Plan, Natural Community Conservation

Plan, or other approved local, regional or state

habitat conservation plan?

X

V. CULTURAL RESOURCES. Would the project:

a) Cause a substantial adverse change in the significance

of a historical resource as defined in §15064.5? X

b) Cause a substantial adverse change in the significance

of an archaeological resource pursuant to § 15064.5? X

c) Directly or indirectly destroy a unique paleontological

resource or site or unique geologic feature? X



Issues

Potentially

Significant

Impact

Less Than

Significant

With

Mitigation

Incorporated

Less Than

Significant

Impact

No

Impact

d) Disturb any human remains, including those interred

outside of formal cemeteries? X

VI. GEOLOGY AND SOILS. Would the project:

a) Expose people or structures to potential substantial

adverse effects, including the risk of loss, injury, or

death involving:

X

i) Rupture of a known earthquake fault, as delineated

on the most recent Alquist-Priolo Earthquake Fault

Zoning map, issued by the State Geologist for the

area or based on other substantial evidence of a

known fault? Refer to Division of Mines and Geology

Special Publication 42.

X

ii) Strong seismic ground shaking? X

iii) Seismic-related ground failure, including liquefaction? X

iv) Landslides? X

b) Result in substantial soil erosion or the loss of

topsoil?

X

c) Be located on a geologic unit or soil that is unstable,

or that would become unstable as a result of the

project, and potentially result in on- or off-site

landslide, lateral spreading, subsidence, liquefaction

or collapse?

X

d) Be located on expansive soil, as defined in Table 18-1-

B of the Uniform Building Code (1994), creating

substantial risks to life or property?

X

e) Have soils incapable of adequately supporting the use

of septic tanks or alternative wastewater disposal

systems where sewers are not available for the

disposal of wastewater?

X

VII. GREENHOUSE GAS EMISSIONS. Would the project:

a) Generate greenhouse gas emissions, either directly or

indirectly, that may have a significant impact on the

environment?

X

b) Conflict with any applicable plan, policy or regulation

of an agency adopted for the purpose of reducing the

emissions of greenhouse gases?

X

VIII. HAZARDS AND HAZARDOUS MATERIALS. Would the project:

a) Create a significant hazard to the public or the

environment through the routine transport, use or

disposal of hazardous materials?

X

b) Create a significant hazard to the public or the

environment through reasonable foreseeable upset

and accident conditions involving the release of

hazardous materials into the environment?

X



Issues

Potentially

Significant

Impact

Less Than

Significant

With

Mitigation

Incorporated

Less Than

Significant

Impact

No

Impact

c) Emit hazardous emissions or handle hazardous or

acutely hazardous materials, substances, or waste

within one-quarter mile of an existing or proposed

school?

X

d) Be located on a site which is included on a list of

hazardous materials sites compiled pursuant to

Government code Section 65962.5 and, as a result,

would it create a significant hazard to the public or

the environment?

X

e) For a project located within an airport land use plan

or, where such a plan has not been adopted, within

two miles or a public airport or public use airport,

would the project result in a safety hazard for people

residing or working in the project area?

X

f) For a project within the vicinity of a private airstrip,

would the project result in a safety hazard for people

residing or working in the project area?

X

g) Impair implementation of or physically interfere with

an adopted emergency response plan or emergency

evacuation plan?

X

h) Expose people or structures to a significant risk of

loss, injury or death involving wildland fires, including

where wildlands are adjacent to urbanized areas or

where residences are intermixed with wildlands?

X

IX. HYDROLOGY AND WATER QUALITY. Would the project:

a) Violate any water quality standards or waste

discharge requirements? X

b) Substantially deplete groundwater supplies or

interfere substantially with groundwater recharge,

such that there would be a net deficit in aquifer

volume or a lowering of the local groundwater table

level (e.g., the production rate of pre-existing nearby

wells would drop to a level which would not support

existing land uses or planned uses for which permits

have been granted)?

X

c) Substantially alter the existing drainage pattern of

the site or area, including through the alteration of

the course of a stream or river, in a manner which

would result in substantial erosion or siltation on- or

off-site?

X

d) Substantially alter the existing drainage pattern of


the course of a stream or river, or substantially

increase the rate or amount of surface runoff in a

manner, which would result in flooding on- or off-

site?

X



Issues

Potentially

Significant

Impact

Less Than

Significant

With

Mitigation

Incorporated

Less Than

Significant

Impact

No

Impact

e) Create a significant adverse environmental impact to

drainage patterns due to changes in runoff flow rates

or volumes?

X

f) Substantially alter the existing drainage pattern of


the course of a stream or river, or substantially

increase the rate or amount of surface runoff in a

manner, which would result in flooding on-or off-

site?

X

g) Create or contribute runoff water which would

exceed the capacity of existing or planned storm

water drainage systems or provide substantial

additional sources of polluted runoff?

X

h) Result in increased impervious surfaces and

associated increased runoff? X

i) Result in significant alteration of receiving water

quality during or following construction? X

j) Result in an increase in pollutant discharges to

receiving waters? Consider water quality parameters

such as temperature, dissolved oxygen, turbidity and

other typical storm water pollutants (e.g. heavy

metals, pathogens, petroleum derivatives, synthetic

organics, sediment, nutrients, oxygen-demanding

substances, and trash).

X

k) Be tributary to an already impaired water body as

listed on the Clean Water Act Section 303(d) list. If so,

can it result in an increase in any pollutant for which

the water body is already impaired?

X

l) Be tributary to environmentally sensitive areas (e.g.

MSCP, RARE, Areas of Special Biological Significance,

etc.)? If so, can it exacerbate already existing

sensitive conditions?

X

m) Have a potentially significant environmental impact

on surface water quality, to either marine, fresh or

wetland waters?

X

n) Otherwise substantially degrade water quality? X

o) Place housing within a 100-year flood hazard area as

mapped on a federal Flood Hazard Boundary or Flood

Insurance Rate Map or other flood hazard delineation

map?

X

p) Place within a 100-year flood hazard area structures

which would impede or redirect flood flows? X

q) Expose people or structures to a significant risk of

loss, injury or death involving flooding, including

flooding as a result of the failure of a levee or dam?

X

r) Inundation by seiche, tsunami, or mudflow? X



Issues

Potentially

Significant

Impact

Less Than

Significant

With

Mitigation

Incorporated

Less Than

Significant

Impact

No

Impact

X. LAND USE AND PLANNING. Would the project:

a) Physically divide an established community? X

b) Conflict with any applicable land use plan, policy, or

regulation of an agency with jurisdiction over the

project (including, but not limited to the general plan,

specific plan, local coastal program, or zoning

ordinance) adopted for the purpose of avoiding or

mitigating an environmental effect?

X

c) Conflict with any applicable habitat conservation plan

or natural community conservation plan? X

XI. MINERAL RESOURCES. Would the project:

a) Result in the loss of availability of a known mineral

resource that would be a value to the region and the

residents of the state?

X

b) Result in the loss of availability of a locally important

mineral resource recovery site delineated on a local

general plan, specific plan or other land use plan?

X

XII. NOISE. Would the project result in:

a) Exposure of persons to or generation of noise levels

in excess of standards established in the local general

plan or noise ordinance, or applicable standards of

other agencies?

X

b) Exposure of persons to or generation of excessive

groundborne vibration or groundborne noise levels? X

c) A substantial permanent increase in ambient noise

levels in the project vicinity above levels existing

without the project?

X

d) A substantial temporary or periodic increase in

ambient noise levels in the project vicinity above

levels existing without the project?

X

e) For a project located within an airport land use plan

or, where such a plan has not been adopted, within

two miles of a public airport or public use airport,

would the project expose people residing or working

in the project area to excessive noise levels?

X

f) For a project within the vicinity of a private airstrip,

would the project expose people residing or working

in the project area to excessive noise levels?

X

XIII. POPULATION AND HOUSING. Would the project:

a) Induce substantial population growth in an area,

either directly (for example, by proposing new homes

and businesses) or indirectly (for example, through

extension of roads or other infrastructure)?

X

b) Displace substantial numbers of existing housing,

necessitating the construction of replacement

housing elsewhere?

X



Issues

Potentially

Significant

Impact

Less Than

Significant

With

Mitigation

Incorporated

Less Than

Significant

Impact

No

Impact

c) Displace substantial numbers of people, necessitating

the construction of replacement housing elsewhere? X

XIV. PUBLIC SERVICES. Would the project result in substantial adverse physical impacts associated with the

provision of new or physically altered governmental facilities, need for new or physically altered

governmental facilities, the construction of which could cause significant environmental impacts, in order

to maintain acceptable service ratios, response times or other performance objectives for any of the public

services:

a) Fire protection? X

b) Police protection? X

c) Schools? X

d) Parks? X

e) Other public facilities? X

XV. RECREATION.

a) Would the project increase the use of existing

neighborhood and regional parks or other

recreational facilities, such that substantial physical

deterioration of the facility would occur or be

accelerated?

X

b) Does the project include recreational facilities or

require the construction or expansion of recreational

facilities, which might have an adverse physical effect

on the environment?

X

XVI. TRANSPORTATION/TRAFFIC. Would the project:

a) Cause an increase in traffic, which is substantial in

relation to the existing traffic load and capacity of the

street system (i.e., result in a substantial increase in

either the number of vehicle trips, the volume to

capacity ratio on roads, or congestion at

intersections)?

X

b) Exceed, either individually or cumulatively, a level of

service standard established by the county

congestion management agency for designated roads

or highways?

X

c) Result in a change in air traffic patterns, including

either an increase in traffic levels or a change in

location that results in substantial safety risks?

X

d) Substantially increase hazards due to a design feature

(e.g., sharp curves or dangerous intersections) or

incompatible uses (e.g., farm equipment)?

X

e) Result in inadequate emergency access? X

f) Result in inadequate parking capacity? X

g) Conflict with adopted policies, plans, or programs

supporting alternative transportation (e.g., bus

turnouts, bicycle racks)?

X



Issues

Potentially

Significant

Impact

Less Than

Significant

With

Mitigation

Incorporated

Less Than

Significant

Impact

No

Impact

XVII. UTILITIES AND SERVICE SYSTEMS. Would the project:

a) Exceed wastewater treatment requirements of the

applicable Regional Water Quality Control Board? X

b) Require or result in the construction of new water or

wastewater treatment facilities or expansion of

existing facilities, the construction of which could

cause significant environmental effects?

X

c) Require or result in the construction of new storm

water drainage facilities or expansion of existing

facilities, the construction of which could cause

significant environmental effects?

X

d) Have sufficient water supplies available to serve the

project from existing entitlements and resources or

are new or expanded entitlements needed?

X

e) Result in a determination by the wastewater

treatment provider, which serves or may serve the

project that it has adequate capacity to serve the

project’s projected demand in addition to the

provider’s existing commitments?

X

f) Be served by a landfill with sufficient permitted

capacity to accommodate the project’s solid waste

disposal needs?

X

g) Comply with federal, state, and local statutes and

regulations related to solid waste? X

XVIII. MANDATORY FINDINGS OF SIGNIFICANCE.

a) Does the project have the potential to degrade the

quality of the environment, substantially reduce the

habitat of a fish or wildlife species, cause a fish or

wildlife population to drop below self-sustaining

levels, threaten to eliminate a plant or animal

community, reduce the number or restrict the range

of a rare or endangered plant or animal or eliminate

important examples of the major periods of California

history or prehistory?

X

b) Does the project have impacts that are individually

limited, but cumulatively considerable?

("Cumulatively considerable" means that the

incremental effects of a project are considerable

when viewed in connection with the effects of past

projects, the effects of other current projects, and

the effects of probable future projects.)

X

c) Does the project have environmental effects, which

will cause substantial adverse effects on human

beings, either directly or indirectly?

X



IV. ENVIRONMENTAL ANALYSIS

This section provides an evaluation of the impact categories and questions contained in the

Environmental Checklist.

I. AESTHETICS

a) Have a substantial adverse effect on a scenic vista? Less than Significant Impact.

The project site is located between Mount Whitney and Double Peak Mountain in a valley of land

with disturbed habitat and soil disturbed by the closed Hanson Operation as well as natural open

space areas. The project site is located within the Barham/Discovery community plan area in the City

of San Marcos. Portions of these community plan areas contain scenic corridors are listed in the San

Marcos General Plan.

Topographically, the site consists of cut slope and fill areas resulting from previous site grading

activities as well as natural open space areas. The project site is located within an overall hillside and

valley terrain. Existing elevations range from a high of approximately 875 feet above mean sea level

(msl) in the southeastern portion of the site to a low of approximately 720 feet msl in the northern

portion of the project site.

Proposed development would occur within in areas that have already been disturbed from past

mining activities. Proposed residential development in Areas A, B, C and D and the future non-

residential mixed-use development (business park) would appear as an extension of existing

development north and east of the project site.

The project will preserve approximately 129 acres of open space areas which provides a visual

amenity from both onsite and offsite. These habitat preservation areas include large areas of coastal

sage scrub which will connect to existing preserve areas to the south of the project site. The

preservation of over half of the project site as open space areas will contribute to scenic vistas in the

area. Project impacts would be less than significant.

b) Substantially damage scenic resources, including, but not limited to, trees, rock outcroppings,

and historic buildings within a State Scenic Highway? No Impact

The project site is located approximately 1.2 miles south of State Route 78 (SR-78). A portion of

SR-78 is recognized as a Scenic Highway by Caltrans; however, that portion is not in the project

vicinity. The portion identified as a Scenic Highway is approximately 50 miles east of the project site

near Anza Borrego (Caltrans 2013). Thus the project would not impact a State scenic highway.

At a local level, SR-78 is designated by the City as a view corridor. The highway corridor provides

view of the Merriam Mountains, Mount Whitney, Double Peak, CSUSM and Palomar Community

College. The proposed development would not impact views to these peaks from SR-78 since it is

situated at a lower elevation.

The City has a Ridgeline Protection and Management Overlay Zone (RPMOZ) which is designed to

protect natural viewsheds and unique natural resources, and to minimize physical impacts to select

primary and secondary ridgelines. These protected primary and secondary ridgelines are shown on



Figure 4-5 of the Conservation and Open Space Element of the City’s General Plan. Development is

not proposed on areas identified as primary or secondary ridgeline.

The project site is vacant and does not support any historic buildings. Cultural resources reports for

the project have not identified any historic buildings on the project site. Therefore the project would

not damage any historic buildings.

In addition, the project site does not support any significant trees, rock outcroppings or historic

buildings as identified or protected by the City’s General Plan. Therefore no impact is identified.

c) Substantially degrade the existing visual character or quality of the site and its surroundings?

Less than Significant Impact

The existing visual character of the area is that of single-family homes to the north, multi-family

homes to the east, and South Lake to the south, location of a future park. The site has varying

topography, with steep slopes in several areas. Natural vegetation on the project site includes a

combination of upland and wetland habitats.

Portion of the project site currently supports stabilized slopes created as a function of the Hanson

Operation closure plan and natural habitat that has grown on areas previously disturbed by the

mining operations. Northwest views to the City and the SR-78 corridor are an existing visual amenity

from the project site.

Visual changes to the site would include grading activities to provide access to the project site, as

well as development of a single-family residential, non-residential mixed use (business park), and an

active recreation park. The originally approved tentative map for the subject site would have

allowed for the construction of residential units in the area where the non-residential mixed use and

public amenities are now proposed. The visual character of this area of Heart of the City is

residential with single-family homes to the north and multi-family residential homes to the east. The

development of residential, non-residential mixed use (business park/retail), and an active park is

consistent with the residential character of this area which is defined by other slopes in the area

with heights up to 80 feet as permitted through the Heart of the City Specific Plan.

Future residential development on the project site (Areas A, B, C and D) will be guided by the

Rancho Coronado Residential Design Guidelines (Appendix A.3 of this document) which detail the

requirements for architecture and landscaping for the future residential areas. A multi-theme

Mediterranean style is proposed for the future residences with a requirement for articulation of

massing to make the homes appear smaller, convey a sense of human scale, and to avoid a

monotonous appearance. A comprehensive landscape plan will further add to the visual interest of

the project and also provide screening from offsite areas.

Future development within the non-residential mixed use development area will be guided by the

requirements of the Heart of the City Specific Plan which requires the smooth masonry, brick, tile,

and tinted or lightly reflective glass. Highly reflective dark glass is not permitted.

Finally, the project will preserve approximately 129 acres of open space areas which provides a

visual amenity from both onsite and offsite. These habitat preservation areas include large areas of

coastal sage scrub which will connect to existing preserve areas to the south of the project site.



As such, the proposed project would not significantly change the visual character or quality of the

site and surroundings, and therefore impacts are determined to be less than significant.

d) Create a new source of substantial light or glare, which would adversely affect day or

nighttime views in the area? Less than Significant Impact

Development of the proposed project would add lighting to an area that is currently undeveloped

and does not have lighting.

Lighting proposed under the project would be guided by standards set by the City of San Marcos,

which requires downward-directed LED lighting, with the exception of specialized streetscape

lighting or architectural detail lighting. These requirements aid in the preservation of dark-sky

conditions, which are needed by the local observatories. Development under the project would also

be required to comply with the City’s lighting standards, and the location, type, and direction of the

lighting would be reviewed during Improvement Plan review to ensure compliance with City

requirements. Thus impacts related to substantial light pollution are determined to be less than

significant.

The active park will have sports fields that may include lighting. At this time there is not a specific

development plan for the park area. It is anticipated that the use of lighting for night games would

be limited and would be subject to timing limits so as to not disturb adjacent residential uses. At the

time a park plan is developed, the park plan would be subject to additional environmental review,

which would include a review of the proposed lighting to determine any impacts related to night

lighting. Therefore, impacts are less than significant.

The project does not propose features that would be characterized as creating a new source of glare

that would adversely affect daytime or nighttime views. Chapter 3 of the Rancho Coronado

Residential Design Guidelines (Appendix A.3 of this document) details the materials and colors to be

used in the future residential development areas. The homes would incorporate earth-toned roof

tiles and stucco surface that will be in soft earth tones. These roof and wall colors and materials are

not significant sources of glare. Section 3.3.3 of the Heart of the City Specific Plan (Appendix A.2 of

this document) details the required materials for future business park development. Required

materials include smooth masonry, brick, tile, and tinted or lightly reflective glass. Highly reflective

dark glass is not permitted.

Since project will use lighting in an unobtrusive manner and will be required to comply with the

lighting standards set for by the City and the proposed materials to be used in the homes and future

mixed-use non-residential area are not glare-inducing, impacts related to lighting and glare would

be less than significant.

II. AGRICULTURE RESOURCES

a) Convert Prime Farmland, Unique Farmland, or Farmland of Statewide Importance (Farmland),

as shown on the maps prepared pursuant to the Farmland Mapping and Monitoring Program

of the California Resources Agency, to non-agricultural use? No Impact

The project site does not fall under areas mapped as prime farmland, unique farmland or farmland

of statewide importance, as determined by the Farmland Mapping and Monitoring Program, as



shown in San Marcos General Plan (Figure 4-4, Agricultural Areas). Therefore, the project would not

result in the conversion of such lands and no impact is identified for this issue area.

b) Conflict with existing zoning for agricultural use, or a Williamson Act contract? No Impact.

The project site is not located within a Williamson Act contract area, as shown in the San Marcos

General Plan (Figure 4-4, Agricultural Areas). Further, the project site is not zoned for agricultural

use. The project site is currently zoned Specific Plan, and that zoning designation will be retained

with implementation of the proposed project. Therefore, no impact is identified for this issue area.

c) Conflict with existing zoning for, or cause rezoning of, forest land (as defined in Public

Resources Code section 12220(g)), timberland (as defined in Public Resources Code section

4526), or timberland zoned Timberland Production (as defined by Government Code section

51104(g))? No Impact

The proposed project is not located in an area that is zoned for forest land, timber land or for timber

production. The project site is zoned Specific Plan and will retain that designation with

implementation of the proposed project. Therefore, no impact is identified.

d) Result in the loss of forest land or conversion of forest land to non-forest use? No Impact

The project site does not support forests, nor is there any forest land adjacent to the project site.

The project development will be adjacent to existing residential development on the north, Twin

Oaks Valley Road to the east and future park space and preserved open space (which is not

forestland) to the west and south. Therefore, the proposed project will not result in the loss of

forest land or the conversion of forest land to non-forest use. No impact is identified for this issue

area.

e) Involve other changes in the existing environment which, due to their location or nature,

could result in conversion of Farmland, to non-agricultural use or conversion of forest land to

non-forest use?? No Impact

The project does not involve other changes in the existing environment which, due to their location

or nature could result in conversion of Farmland to non-agricultural use or conversion of forest land

to non-forest use. The project site does not support any agricultural or timber uses, nor is it adjacent

to such uses. Therefore, no impact is identified for this issue area.

III. AIR QUALITY

An air conformity analysis was prepared for the project by Scientific Resources Associates (2014a)

and is included as Appendix B.

a) Conflict with or obstruct implementation of the applicable air quality plan? Less Than

Significant Impact

Projects that are consistent with existing General Plan documents, which are used to develop air

emissions budgets for the purpose of air quality planning and attainment demonstrations, would be

consistent with the San Diego Air Basin’s (SDAB) air quality plans, including the Regional Air Quality



Strategy (RAQS) and the State Implementation Plan (SIP). Both of these air quality plans contain

strategies for the region to attain and maintain the ambient air quality standards. Provided a

project proposes the same or less development as accounted for in the General Plan document, and

provided the project is in compliance with applicable Rules and Regulations adopted by the San

Diego Air Pollution Control District (SDAPCD) through their air quality planning process, the project

would not conflict with or obstruct implementation of the RAQS or SIP.

The project involves construction of 346 single- and paired single-family residential units in four

residential areas, along with development of a 24.1-acre mixed-use development. While specific

development is not proposed within this area at this time, the environmental analysis assume 90

percent of the non-residential mixed use area would be developed with business park uses and the

remaining 10 percent would be retail with a total of 240,000 s.f. developed on the 24.1 acres. The

project will serve existing and future housing needs within the City of San Marcos, and is consistent

with the City’s Heart of the City Specific Plan.

The project will comply with all applicable rules and regulations that have been adopted as part of

the SIP. Because the project is consistent with the goals of the RAQS and SIP, the project would not

conflict with or obstruct implementation of the RAQS and SIP, and impacts would be less than

significant.

In summary, implementation of the project would not conflict with or obstruct implementation of

applicable air quality plans and a less than significant impact is identified.

b) Violate any air quality standard or contribute substantially to an existing or projected air

quality violation? Less Than Significant Impact

Table 3 shows the state and federal attainment status for criteria pollutants in the San Diego Air

Basin (SDAB). As shown in Table 3, the SDAB is a nonattainment area for the state and federal O3

standards, and for the state PM10 and PM2.5 standards.

Table 3. Attainment Status of Criteria Pollutants in San Diego Air Basin

Pollutant State Federal

1-hour Ozone (O3) Serious Nonattainment Revoked June 2005

8-hour O3 Nonattainment Marginal Nonattainment

Particulate Matter−10 microns (PM10) Nonattainment Unclassified

Particulate Matter−2.5 microns (PM2.5) Nonattainment Unclassified/Attainment

Carbon Monoxide (CO) Attainment Maintenance

Nitrogen Dioxide (NO2) Attainment Unclassified/Attainment

Sulfur Dioxide (SO2) Attainment Attainment

Lead Attainment Unclassified/Attainment

All others Unclassified/Attainment N/A

Source: California Air Resources Board: http://www.arb.ca.gov/desig/adm/adm.htm. April 2013.

The SCAQMD establishes significance criteria for air quality emissions. The aggregate project-related

maximum levels are shown in Table 4. Any project with daily construction- or operation-related

emissions that exceed any of the following thresholds should be considered as having an individually

and cumulatively significant air quality impact.



Table 4. Screening-Level Criteria for Air Quality Impacts

Pollutant Total Emissions

Construction Emissions Lb. per Day

Respirable Particulate Matter (PM10) 100

Fine Particulate Matter (PM2.5) 100

Oxides of Nitrogen (NOx) 250

Oxides of Sulfur (SOx) 250

Carbon Monoxide (CO) 550

Volatile Organic Compounds (VOCs)1

137

Operational Emissions Lb. Per Hour Lb. per Day Tons per Year

Respirable Particulate Matter (PM10) --- 100 15

Fine Particulate Matter (PM2.5) --- 100 15

Oxides of Nitrogen (NOx) 25 250 40

Oxides of Sulfur (SOx) 25 250 40

Carbon Monoxide (CO) 100 550 100

Lead and Lead Compounds --- 3.2 0.6

Volatile Organic Compounds (VOC)2

--- 137 15

To determine whether a project would result in emissions that would violate any air quality

standard or contribute substantially to an existing or projected air quality violation; project

emissions may be evaluated based on the quantitative emission thresholds established by the San

Diego APCD.

As part of its air quality permitting process, the APCD has established thresholds in Rule 20.2 for the

preparation of Air Quality Impact Assessments (AQIA). For CEQA purposes, these screening criteria

can be used as numeric methods to demonstrate that a project’s total emissions would not result in

a significant impact to air quality. Since APCD does not have AQIA thresholds for emissions of VOCs,

the use of the threshold for VOCs from the City of San Diego’s Significance Thresholds (City of San

Diego 2007) is appropriate. The screening thresholds are presented in Table 4.

The thresholds listed in Table 4 represent screening-level thresholds that can be used to evaluate

whether project-related emissions could cause a significant impact on air quality. Emissions below

the screening-level thresholds would not cause a significant impact. In the event that emissions

exceed these thresholds, modeling would be required to demonstrate that the project’s total air

quality impacts result in ground-level concentrations that are below the State and Federal Ambient

Air Quality Standards, including appropriate background levels. For nonattainment pollutants

(ozone, with ozone precursors NOx and VOCs, and PM10), if emissions exceed the thresholds shown

in Table 4, the project could have the potential to result in a cumulatively considerable net increase

in these pollutants and thus could have a significant impact on the ambient air quality.

Construction Emissions

Construction activities, including soil disturbance dust emissions and combustion pollutants from

on-site construction equipment and from off-site trucks hauling dirt, cement or building materials,

will create a temporary addition of pollutants to the local airshed. The proposed project will involve

grading activities. Grading for the project includes 2,608,200 cubic yards (cy) of cut and 2,853,800 of

fill and will balance onsite. The grading quantities assume a 15 to 18 percent bulking factor. No



offsite export or import will be required for the project. Due to underlying bedrock conditions,

blasting will be required as part of the project construction. The following equipment will be used on

site for construction:

• Tractor/backhoe

• Dozer-D9

• Hydraulic Crane

• Loader/Grader

• Side Boom

• Water Truck

• Rock Crusher (potential)

• Concrete Truck

• Concrete Pump

• Dump/Haul Trucks

• Paver/Blade

• Roller/Compactor

• Scraper

• Drill Rig (for borings in rock prior to blasting)

Project phasing will include an overall grading phase commencing in 2014. The grading phase would

include blasting and rock crushing. Phase 1 construction will start in 2015 and is anticipated to be

completed by late 2016 or early 2017. Phase 1 includes Residential Area A and B (126 dwelling

units), Backbone Road from Santa Barbara Drive to North Village Drive, and North Village Drive

extended west to Backbone Road.

Phase 2 construction is anticipated to start in 2017 and be complete by 2020. Phase 2 includes

construction of 220 dwelling units in Residential Areas C and D; construction of the 24.1-acre mixed-

use portion of the project, which will include 90 percent business park and 10 percent retail;

construction of a 38-acre active park; construction of Backbone Road from North Village Drive to

South Village Drive; construction of South Village Drive extended west to Backbone Road;

installation of a new signal for access to the mixed use site, and construction of the access road for

the mixed use site.

Fugitive dust emissions associated with blasting were estimated based on the U.S. EPA’s emission

factor for blasting for coal mining to remove overburden, which is a similar process.

Table 5a presents the model results for the construction of the project. Construction projects within

the City of San Marcos would be required to implement fugitive dust control measures during

grading, which would include watering the site a minimum of twice daily to control dust, as well as

reducing speeds on unpaved surfaces to 15 mph or less, replacing ground cover in disturbed areas

quickly, and reducing dust during loading/unloading of dirt and other materials. Also, projects

would utilize low-VOC paints that would not exceed 100 grams of VOC per liter for interior surface

and 150 grams of VOC per liter for exterior surfaces, in accordance with the requirements of APCD

Rule 67.0 for architectural coatings. These two requirements have been identified as project design

features for the project in Table 2. Thus Table 5a presents an estimate of the maximum daily

construction emissions, assuming that these construction project design features will be employed.



Table 5a. Construction Emissions – Proposed Project

Construction Project/Phase VOC NOx CO SO2 PM10 PM2.5

Site Grading

Grading – Area C & D

Fugitive Dust – Blasting - - - - 30.79 9.23

Explosives Emissions - 8.50 33.50 - - -

Fugitive Dust - Rock Crushing - - - - 7.12 2.14

Fugitive Dust - Earthmoving - - - - 3.17 1.41

Off-Road Diesel 12.98 148.08 82.44 0.14 6.71 6.21

Hauling Truck Trips 14.82 39.10 217.83 0.04 0.32 0.19

Worker Trips 0.15 0.17 1.88 0.004 0.31 0.09

Total 27.95 195.85 335.65 0.18 48.42 19.27

Significance Threshold 137 250 550 250 100 100

Above Threshold? No No No No No No

Grading – Area B


Off-Road Diesel 11.67 136.15 75.78 0.12 6.02 5.54


Worker Trips 0.13 0.15 1.63 0.003 0.27 0.07

Total 26.45 174.97 292.82 0.16 10.07 7.24



Grading – Area A


Off-Road Diesel 11.67 136.15 75.78 0.12 6.02 5.54


Worker Trips 0.13 0.15 1.63 0.003 0.27 0.07

Total 26.25 174.44 289.89 0.16 9.65 7.20



Grading – Area M-3





Off-Road Diesel 13.70 153.34 86.29 0.14 7.09 6.59


Worker Trips 0.15 0.17 1.88 0.004 0.31 0.09

Total 28.63 201.01 338.96 0.18 48.81 19.65


Above Threshold No No No No No No




Grading – Backbone Roadway





Off-Road Diesel 12.96 147.76 82.32 0.14 6.70 6.20


Worker Trips 0.15 0.17 1.88 0.004 0.31 0.09

Total 27.83 195.28 334.14 0.18 48.52 19.27



Grading - Channel





Off-Road Diesel 11.64 135.86 75.67 0.12 6.01 5.53


Worker Trips 0.13 0.15 1.63 0.003 0.27 0.07

Total 25.80 181.53 317.02 0.15 47.87 18.58



Maximum Simultaneous

Construction Emissions, Grading 28.63 201.01 338.96 0.18 48.81 19.65



Phase 1 Construction

Building Construction

Building Construction Off-Road

Diesel 3.66 30.03 18.74 0.03 2.11 1.99

Building Construction Vendor Trips 2.57 12.33 13.73 0.03 0.95 0.40

Building Construction Worker Trips 4.43 1.36 14.88 0.03 2.49 0.67

Total 10.66 43.72 47.35 0.09 5.55 3.06



Paving

Asphalt Offgassing 0.28 - - - - -

Paving Off-Road Diesel 5.30 52.39 28.79 0.051 2.93 2.76

Paving On-Road Diesel 0.23 1.09 1.21 0.002 0.08 0.04

Paving Worker Trips 0.37 0.11 1.24 0.003 0.21 0.06

Total 6.18 53.59 31.24 0.06 3.22 2.86






Architectural Coatings Use

Architectural Coating Offgassing 24.31 - - - - -

Off-Road Diesel 0.41 2.57 1.90 0.003 0.22 0.22

Architectural Coatings Worker Trips 0.88 0.27 2.97 0.006 0.50 0.13

Total 25.60 2.84 4.87 0.01 0.72 0.35




Construction Emissions, Phase 1 36.26 97.31 78.59 0.14 8.78 5.92



Phase 2 Construction

Building Construction

Building Construction Off-Road

Diesel 3.10 26.41 18.13 0.03 1.78 1.67

Building Construction Vendor Trips 2.96 13.81 17.02 0.04 1.28 0.50

Building Construction Worker Trips 5.26 1.54 16.67 0.04 3.41 0.92

Total 11.32 41.76 51.82 0.11 6.47 3.09



Paving

Asphalt Offgassing 0.28 - - - - -

Paving Off-Road Diesel 4.43 43.19 27.94 0.051 2.37 2.23

Paving On-Road Diesel 0.18 0.85 1.04 0.002 0.08 0.03

Paving Worker Trips 0.32 0.09 1.01 0.003 0.21 0.06

Total 5.21 44.13 29.99 0.06 2.66 2.32



Architectural Coatings Use

Architectural Coating Offgassing 22.14 - - - - -

Off-Road Diesel 0.33 2.19 1.87 0.002 0.17 0.17

Architectural Coatings Worker Trips 1.05 0.31 3.32 0.009 0.68 0.18

Total 23.52 2.50 5.19 0.01 0.85 0.35




Construction Emissions, Phase 2 40.05 88.38 87.00 0.18 9.98 5.76





As shown in Table 5a, maximum daily emissions of all criteria pollutants would be below the

significance thresholds for all criteria pollutants. The mitigation measures assumed are as follows:

Operational Emissions

Operational impacts associated with the Rancho Coronado Specific Plan would include emissions

associated with vehicular traffic, as well as area sources such as energy use, consumer products use,

and architectural coatings use for maintenance purposes. Emissions associated with project

operations were estimated using the CalEEMod Model, based on the project’s overall trip

generation of 8,926 ADT (RBF Consulting 2014). For the purpose of estimating emissions, it was

assumed that each residence would have a fireplace, and that the fireplaces would be natural gas-

fired only.

Table 5b provides a summary of the estimated operational emissions for the Rancho Coronado

Specific Plan project.

Table 5b. Operational Emissions – Proposed Project

VOC NOx CO SOx PM10 PM2.5

Summer Day, Lbs/day

Area Sources 64.24 0.33 28.71 0.001 0.62 0.62

Energy Use 0.50 4.38 2.68 0.03 0.35 0.35

Vehicular Emissions 60.41 45.61 225.74 0.63 42.66 11.85

TOTAL 125.15 50.33 257.13 0.66 43.63 12.81

Significance Screening Criteria 137 250 550 250 100 55

Above Screening Criteria? No No No No No No

Winter Day, Lbs/day

Area Sources 64.24 0.33 28.71 0.001 0.62 0.62

Energy Use 0.50 4.38 2.68 0.03 0.35 0.35

Vehicular Emissions 72.04 48.44 242.49 0.60 42.67 11.85

TOTAL 136.78 53.15 273.87 0.62 43.63 12.81

Significance Screening Criteria 137 250 550 250 100 55

Above Screening Criteria? No No No No No No

Operational emissions associated with the Rancho Coronado Specific Plan would be below the

significance criteria for operations. Air quality impacts would therefore be less than significant.

CO Hot Spot Analysis

Operational emissions associated with the Rancho Coronado Specific Plan would be below the

significance criteria for operations. Air quality impacts would therefore be less than significant.

Projects that involve traffic impacts may have the potential for CO “hot spots” to occur (i.e., high

concentrations of CO at intersections). The Traffic Impact Analysis Report (RBF Consulting 2014)

indicated that project-related traffic would result in a significant impact at the following

intersections:



2016 Conditions

• Twin Oaks Valley Road and SR-78 Eastbound Ramps

2020 Conditions


2030 Conditions


• Twin Oaks Valley Road and Discovery Street/Barham Drive

To verify that the project would not cause or contribute to a violation of the CO standard, a

screening evaluation of the potential for CO “hot spots” was conducted. The Traffic Impact Analysis

evaluated whether or not there would be a decrease in the level of service at the roadways and/or

intersections affected by the Project. The potential for CO “hot spots” was evaluated based on the

results of the Traffic Impact Analysis. The Caltrans ITS Transportation Project-Level Carbon

Monoxide Protocol (Caltrans 1998) should be followed to determine whether a CO “hot spot” is

likely to form due to Project-generated traffic. In accordance with the Protocol, CO “hot spots” are

typically evaluated when (a) the level of service (LOS) of an intersection or roadway decreases to a

LOS E or worse; (b) signalization and/or channelization is added to an intersection; and (c) sensitive

receptors such as residences, commercial developments, schools, hospitals, etc. are located in the

vicinity of the affected intersection or roadway segment.

To evaluate the potential for CO “hot spots,” the procedures in the Caltrans ITS Transportation

Project-Level Carbon Monoxide Protocol were used. As recommended in the Protocol, CALINE4

modeling was conducted for the intersections identified above for the scenario without Project

traffic, and the Project scenarios. Modeling was conducted based on the guidance in Appendix B of

the Protocol to calculate maximum predicted 1-hour CO concentrations. Predicted 1-hour CO

concentrations were then scaled to evaluate maximum predicted 8-hour CO concentrations using

the recommended scaling factor of 0.7 for urban locations.

Inputs to the CALINE4 model were obtained from the Traffic Impact Analysis Report for the Rancho

Coronado Specific Plan (RBF Consulting 2014). As recommended in the Protocol, receptors were

located at locations that were approximately 3 meters from the mixing zone, and at a height of 1.8

meters. Average approach and departure speeds were assumed to be 1 mph to account for

congestion at the intersection and provide a worst case estimate of emissions. Emission factors for

those speeds were estimated from the EMFAC2007 emissions model (ARB 2007) for 2011 for

Existing plus Project conditions, 2020 for Phase II implementation, and 2030 for Phase III

implementation.

In accordance with the Caltrans ITS Transportation Project-Level Carbon Monoxide Protocol, it is

also necessary to estimate future background CO concentrations in the project vicinity to determine

the potential impact plus background and evaluate the potential for CO “hot spots” due to the

project. As a conservative estimate of background CO concentrations, the existing maximum 1-hour

background concentration of CO that was measured at the Escondido monitoring station for the

period 20010 to 2012 of 4.4 ppm was used to represent future maximum background 1-hour CO



concentrations. This is a conservative assumption, as the monitoring station is located in a

congested area in Escondido. The existing maximum 8-hour background concentration of CO that

was measured at the Escondido monitoring station during the period from 2010 to 2012 of 3.61

ppm was also used to provide a conservative estimate of the maximum 8-hour background

concentrations in the project vicinity. CO concentrations in the future may be lower as inspection

and maintenance programs and more stringent emission controls are placed on vehicles.

The CALINE4 model outputs are provided in Appendix A of the air quality report (Appendix B of this

document). Table 6 presents a summary of the predicted CO concentrations (impact plus

background) for the intersections evaluated. As shown in Table 6, the predicted CO concentrations

would be substantially below the 1-hour and 8-hour NAAQS and CAAQS for CO. Therefore, no

exceedances of the CO standard are predicted, and the project would not cause or contribute to a

violation of this air quality standard.

Table 6. CO Hot Spot Evaluation – Predicted CO Concentrations, ppm

Near Term - 2016

Intersection Existing plus Project

Maximum 1-hour Concentration Plus Background, ppm

CAAQS = 20 ppm; NAAQS = 35 ppm; Background 4.4 ppm

am pm

Twin Oaks Valley Rd./SR-78 EB Ramps 5.3 5.3


CAAQS = 9.0 ppm; NAAQS = 9 ppm; Background 3.24 ppm

Twin Oaks Valley Rd./SR-78 EB Ramps 4.24

2020



am pm





2030



am pm


Twin Oaks Valley Rd./Barham Dr./Discovery St. 4.9 5.0




Twin Oaks Valley Rd./Barham Dr./Discovery St. 4.03



c) Result in a cumulatively considerable net increase of any criteria pollutant for which the

project region is non-attainment under an applicable federal or state ambient air quality

standard (including releasing emissions which exceed quantitative thresholds for ozone

precursors)? Less Than Significant Impact

The San Diego Air Basin is a nonattainment area for the state and federal O3 standards, and for the

state PM10 and PM2.5 standards. Evaluating whether the project could result in a cumulatively

considerable impact on air quality relies on both the project’s consistency with the RAQS and SIP,

which address attainment of the O3 standards, and the potential for the project to result in a

cumulatively considerable impact due to particulate emissions.

As part of the RAQS and SIP planning process, the SDAPCD develops an emission inventory, based on

projections from the San Diego Association of Governments (SANDAG), of growth in the region as

well as on information maintained by the SDAPCD on stationary source emissions within the SDAB.

The SDAPCD then uses the emission inventory to conduct airshed modeling, which provides a

demonstration that the SDAB will attain and maintain the O3 standards. Provided a project’s

emissions are consistent with the projections within the RAQS and SIP, the project would not result

in a cumulatively considerable impact on O3 within the SDAB.

With regard to emissions of O3 precursors NOx and VOCs during construction, the SIP includes

emissions associated with construction in its emissions budget and therefore within its attainment

demonstration. The O3 precursor emissions associated with project construction are well below the

screening level thresholds and are well within the construction emissions budget contained in the

SIP, which includes a demonstration that the SDAB will attain and maintain the O3 standards. Thus

because the project will be consistent with the SIP and therefore consistent with the attainment

demonstration for O3 attainment contained within the SIP, the project would not result in a

cumulatively considerable impact that would cause or contribute to a violation of the O3 standard.

Because the Proposed Project would result in emissions below the significance thresholds for all

nonattainment pollutants, the project would not result in additional emissions of O3 precursors

above that projected in the attainment demonstration for O3. The project will therefore not result

in a cumulatively considerable impact on O3 levels within the SDAB.

No simultaneous major construction projects are anticipated within 100 meters of the project site.

Furthermore, particulate emissions for both construction and operations are below the significance

thresholds. Therefore, no cumulatively considerable PM10 impact would result from construction or

operation of the project. Impacts would be less than significant.

d) Expose sensitive receptors to substantial pollutant concentrations? Less Than Significant

Impact

Sensitive receptors are defined as schools, hospitals, resident care facilities, or day-care centers, as

well as residential receptors in the project vicinity. The threshold concerns whether the project

could expose sensitive receptors to substantial pollutant concentrations, either of criteria pollutants,

or of toxic air contaminants (TACs).

If a project has the potential to result in emissions of any TAC which result in a cancer risk of greater

than 10 in 1 million or substantial non-cancer risk, the project would be deemed to have a



potentially significant impact. Residential uses are not land uses that would emit substantial

amounts of toxic air contaminants. The truck traffic that would be associated with the construction

activities would be confined to onsite trips to redistribute excavated material and minor on-road

trips to deliver construction materials. Toxic air contaminant impacts would be less than significant.

e) Create objectionable odors affecting a substantial number of people? Less Than Significant

Impact

Project construction could result in minor amounts of odor compounds associated with diesel heavy

equipment exhaust. These compounds would be emitted in various amounts and at various

locations during construction. Odors are highest near the source and would quickly dissipate offsite;

any odors associated with construction would be temporary. Due to the temporary nature of

construction odors and the anticipated dissipation of odors offsite, impacts during construction

would be less than significant.

The project proposes residential and non-residential mixed use development (e.g., office, business

park, retail) and would not include land uses that would be sources of nuisance odors. Thus the

potential for odor impacts associated with the project is less than significant.

IV. BIOLOGICAL RESOURCES

A Biological Technical Report was prepared for the project by Helix Environmental (2014). The

complete report is included as Appendix C of this document. The report provides a description of

biological surveys performed to date, summarizes biological resources present, assesses proposed

impacts to sensitive biological resources, and proposes compensatory mitigation measures for

project impacts.

Biological Resources Background/Habitat Loss Permit

The project site sits within the boundaries of the former Hanson mining site. The eastern and

northern portions of the former Hanson mining site are disturbed from past aggregate mining

activities and the remainder of the site contains undeveloped native habitat. All upland habitat

impacts associated with the mining and the current residential project have been previously

analyzed within the approved Habitat Loss Permit (HLP; HLP 03-08) approved by the City on

December 23, 2003 and approved by the Wildlife Agencies on January 23, 2004.

The project development is proposed in areas that are disturbed from previous mining and cleared

following the initial HLP approval, although some natural jurisdictional areas still remain and will be

impacted. This is analyzed under the biological resources thresholds, below.

The project will be relocating the primary drainage to the west of the existing location, creating a

widened channel bottom and manufactured earthen slopes along both sides that will be restored to

riparian and sage scrub habitat. Overall riparian habitat will be increased over the long term

following restoration. Any impacts to jurisdictional areas will be reviewed and permitted separately

though agency wetland permits.

The HLP authorizes loss of 40.5 acres of coastal sage scrub (CSS) including 0.7 acres of offsite

impacts, 4.5 acres of native grassland (NG), 11.5 acres of eucalyptus woodland, 23.9 acres of



disturbed habitat, 0.6 acre of ornamental, and 49.5 acres of developed land. Under the HLP the

project was conditioned to preserve 81.0 acres of CSS onsite.

The following project design measures shall be carried forward from the HLP conditions to minimize

impacts to biological resources and are identified as mitigation measures for the project.

Implementation of these mitigation measures will be required as a condition of project approval.

MM-BIO-A The clearing and grubbing of sensitive habitats shall occur outside of the bird

breeding season (February 15 to August 31), unless a qualified biologist

demonstrates to the satisfaction of the City and the Wildlife Agencies that all

nesting is complete. The qualified biologist would need to be federally permitted

for coastal California gnatcatcher if the habitat being cleared has potential to


MM-BIO-B Temporary perimeter fencing shall be installed to separate the proposed

development and the fuel management zones from any CSS areas to the preserved

under the HLP. The removal of temporary fencing is only to occur after all clearing

and construction has been completed.

MM-BIO-C Lots adjacent to biological open space will have permanent fencing and no gates

between the development and the open space; (a) landscaping will be restricted to

native and/or non-invasive plant species; and (b) Best Management Practices

(BMPs) during construction in accordance with Nation Pollutant Discharge

Elimination Systems General Construction Permit requirements will be

implemented.

MM-BIO-D A biological monitor will be on-site when habitat is being cleared, and/or

construction activities are occurring within 100 feet of a Biological Open Space

Easement boundary. Permanent signs must be placed every 100 feet along the

fence bordering the preserve. The signs must be corrosion resistant, no less than

three feet above the ground surface, have minimum dimensions of 6” x 9”, and

must state the following:



By Easement

Information:


MM-BIO-E A conservation easement shall be placed over all on-site mitigation. Additionally,

the applicant shall insure that the biological open space is deeded to a nature

conservancy acceptable to the planning Division Director for maintenance and

monitoring purposes.

MM-BIO-F Manufactured slopes will be revegetated with appropriate native species in

consultation with the Wildlife Agencies. The landscape plan and construction

documents will be approved by the City Engineer, Planning Director, and Fire

Marshal prior to issuance of building permits.



MM-BIO-G Any lands providing mitigation/preservation for the project shall be held in

perpetuity in accordance with a habitat management plan to be approved by the

City and the Wildlife Agencies.

a) Have a substantial adverse effect, either directly or through habitat modifications, on any

species identified as a candidate, sensitive, or special status species in local or regional plans,

policies, or regulations, or by the California Department of Fish and Game or U.S. Fish and

Wildlife Service? Less Than Significant with Mitigation Incorporated

Sensitive Plant Species Observed on the Project Site

Focused surveys for sensitive plants within the study area were performed RECON in 2001 and were

verified as part of the HLP process. Sensitive plant surveys were conducted on foot and focused on

those areas supporting native vegetation communities rather than the highly disturbed mining

areas, which supported little vegetation of any kind. Any rare plants that were observed were

mapped on aerial photographs. Two sensitive plant, Wart-stemmed ceanothus and summer holly

was observed during surveys conducted in 2001. See Figure 5 of the Biological Technical Report

(Appendix C of this document) for the location of sensitive species.

Sensitive Animal Species Observed on the Project Site

A total of 34 animal species (including one listed species) were observed/detected within the project

boundaries and include: 46 birds, and 1 mammal species. The only listed species observed is the

coastal California gnatcatcher. Three animal species observed on site are considered sensitive:

coastal California gnatcatcher, yellow warbler, and yellow-breasted chat. The results of most recent

focused surveys for the least Bell’s vireo were negative. See Figure 5 of the Biological Technical

Report (Appendix C of this document) for the location of sensitive species.

Analysis of Direct Impacts to Sensitive Species

No direct take of habitat occupied by the California gnatcatcher will result from project

implementation. Additionally, no impacts to wart-stemmed ceanothus and summer holly would

occur. Impacts would occur to riparian habitat occupied by the yellow warbler and yellow-breasted

chat. These impacts are considered significant (Impact BIO-1). Implementation of mitigation

measures MM-BIO-1A and BIO-1B, which will be required as condition of project approval would

reduce this impact to below a level of significance, as it would creation, enhance and preserve

riparian habitats both on and offsite, which would provide habitat for the yellow warbler and

yellow-breasted chat.

MM-BIO-1A Impacts to 0.23 acre southern riparian forest, 0.15 acre riparian woodland,

1.43 acres southern willow scrub, 0.90 acre freshwater marsh, 0.33 acre mule fat

scrub, and 0.09 SWS/FWM habitat will be mitigated at a 3:1 ratio. Impacts to

0.85 acres disturbed wetland will be mitigated at a 2:1 ratio. Impact to 0.02 acre

streambed will be mitigated at a 1:1 ratio as detailed in Table 7a for a total of

8.89 acres of mitigation. Mitigation includes a combination of onsite and offsite

creation and enhancement with 6.47 acres of creation and 0.30 acres of

enhancement occurring onsite and 1.07 1.27 acres creation mitigation credit

equivalents and 1.05 acres enhancement credits at the North County Habitat Bank.



Table 7a. Mitigation Requirements for Rancho Coronado (acres)

Vegetation Community Existing Impacts

Required

Mitigation Onsite

Mitigation

Offsite

Mitigation Total Ratio† Area

Riparian woodland (62000) 0.15 0.15 3:1 0.45

6.47

Creation

0.30

Enhancement

1.07

1.27

Creation1

1.05

Enhancement

7.54

7.74

Creation

1.35

Enhancement

Southern riparian forest (61300) 1.72 0.23 3:1 0.69

Southern willow scrub (63320) 1.43 1.43 3:1 4.29

Southern willow scrub/ Freshwater Marsh

(63320/52400) 0.09 0.09 3:1 0.27

Mule fat scrub (63310) 0.33 0.33 3:1 0.99

Freshwater marsh (52400) 0.90 0.16 3:1 0.48

Disturbed wetland (11200) 0.85 0.85 2:1 1.70

Open water (13100) 1.56 0.0 N/A 0

Streambed 0.02 0.02 1:1 0.02

Detention basin (12000) 0.2 0.2 1:1 0.20

7.25 3.46 8.89

9.09 6.77 2.12

8.89

9.09

Notes:

*All areas are presented in acre(s) rounded to the nearest 0.01 **

Riparian habitat creation will be comprised of one or more of the other riparian vegetation communities present on site 10.37 creation credits which is equivalent to 1.071.27 acres of mitigation credit



MM-BIO-1B The preparation of a riparian restoration plan will be required as a condition of the

mitigation for impacts to riparian vegetation communities. The plan will be require

review and approval by the City and include the following.

• All final specifications and topographic-based grading, planting, and

irrigation plans (0.5-foot contours and typical cross-sections) for the

creation/restoration sites. All wetland mitigation areas shall be graded to

the same elevation as adjacent existing jurisdictional wetlands areas, and/or

to within 1 foot of the groundwater table, and shall be left in a rough grade

state with micro topographic relief (including channels for wetlands) that

mimics natural topography, as directed by the City and Resource Agencies.

All plantings shall be installed in a way that mimics natural plant


• Planting palettes (plant species, size, and number/acre) and seed mix (plant

species and pounds/acre). Unless otherwise approved by the City and

Resource Agencies, only locally native species (no cultivars) obtained from

as close to the project area as possible shall be used. The source and proof

of local nativeness of all plant material and seed shall be provided;

• Container plant survival shall be 80 percent of the initial plantings for the

first year;

• A final implementation schedule that indicates when all riparian/wetland

impacts, as well as riparian/wetland creation/restoration grading, planting,

and irrigation, will begin and end. Necessary site preparation and planting

shall be completed during the concurrent or next planting season (i.e., late

fall to early spring). Any temporal loss of habitat caused by delays in

riparian/wetland habitat creation/restoration shall be offset through like

habitat creation/restoration at a 0.5:1 ratio for every 6 months of delay

(i.e., 1:1 for 12 months delay, 1.5:1 for 18 months delay, etc.). In the event

that the project applicant is wholly or partly prevented from performing

obligations under the final plans (causing temporal losses due to delays)

because of unforeseeable circumstances or causes beyond the reasonable

control, and without the fault of negligence of the project applicant,

including but not limited to natural disasters (e.g., earthquakes, etc.), labor

disputes, sudden actions of the elements (e.g., further landslide activity), or

actions or inaction by federal or state agencies, or other governments, the

project applicant will be excused by such unforeseeable cause(s);

• Five years of success criteria for wetland/riparian creation/restoration

areas, including separate percent cover criteria for herbaceous understory,

shrub midstory, and tree overstory, and a total percent absolute cover for

all 3 layers at the end of 5 years; evidence of natural recruitment of multiple

species for all habitat types; 0 percent coverage for Cal-IPC’s “Invasive Plant

Inventory” species, and no more than 10 percent coverage for other




• A minimum of 5 years of maintenance and monitoring of riparian/wetland

creation/restoration areas, unless success criteria are met earlier and all

artificial water supply has been off for at least 2 years

• A qualitative and quantitative vegetation monitoring plan with a map of

proposed sampling locations. Photo points shall be used for qualitative

monitoring and stratified-random sampling shall be used for all quantitative

monitoring;

• Contingency measures in the event of creation/restoration failure;

• Annual mitigation maintenance and monitoring reports shall be submitted

to the City and Resource Agencies no later than December 1 of each year;

• A wetland delineation shall be done to confirm that USACE and CDFW

jurisdictional wetlands have been successfully created/restored prior to

final approval of creation/restoration sites.

Implementation of mitigation measures MM-BIO-1A and MM-BIO-1B will reduce impacts to

sensitive riparian habitats to below a level of significance.

Migratory Bird Treaty Act (MBTA) Species

Additionally the project has the potential to impact avian species protected under the Migratory

Bird Treaty Act (MBTA) if habitat clearing occurs during the breeding season. This represents a

significant impact (Impact BIO-2). Implementation of mitigation measures MM-BIO-2, which will be

required as a condition of project approval, will reduce this impact to below a level of significance.

MM-BIO-2 Potential direct impacts to bird species covered under the MBTA will be mitigated

by restricting brushing and grading to outside of the breeding season of most bird

species (general breeding season is February 15 to August 31). Grubbing, grading,

or clearing during the breeding season of MBTA covered species could occur if it is

determined via a pre-construction survey that no nesting birds (or birds displaying

breeding or nesting behavior) are present immediately prior to grubbing, grading, or

clearing and will require approval of the City that no breeding or nesting avian

species are present in the vicinity of the grubbing, grading, or clearing. The City

shall be notified of any sensitive bird species identified during the pre-construction

surveys.

Analysis of Indirect Impacts to Sensitive Species

Indirect impacts that may be caused by implementation of the proposed project are associated with

edge effects. Edge effects occur when disturbance, development, or grading traverse an

undeveloped area with substantial native lands surrounding the impact area. Edge effects include

human activity, invasive plant species, nuisance animal species, animal behavioral changes, night

lighting, and roadkill. Additionally, the proposed project has potential to cause temporary indirect

impacts due to noise.

Human Activity − Increases in human activity in an area often result in degradation of sensitive

vegetation by further fragmenting habitat through creation of trails, removal of existing vegetation,



and illegal dumping (landscape debris, trash, and other refuse). Human activity in the adjacent

habitat is proposed to be controlled by project fencing and monitoring and management

requirements. Still, these impacts would be considered significant (Impact BIO-3). Implementation

of mitigation measures MM-BIO-3, which would be required as a condition of project approval,

would reduce the impact to below a level of significance.

MM-BIO-3 To reduce edge effects, on-site human activity, and potential impacts related to the

introduction of exotic and domestic animals, the biological open space lots shall be

actively managed and monitored. The required habitat management plan (as

detailed in MM-BIO-1B) shall ensure that access be restricted to developed areas.

Permanent fencing shall be provided for all backyards abutting proposed project

open space. In addition, preserved habitat shall be posted with signs precluding

access due to habitat sensitivity and prohibiting dumping. Residents shall be

educated in access restrictions, control of domestic animals, prevention of irrigation

runoff, and sensitivity of habitats on site.

Invasive Plants − Invasive plants have potential to spread from developed or disturbed areas to

adjacent native habitats. Such invasive species can displace native vegetation reducing the diversity

of native habitats and potentially increasing flammability, changing ground and surface water levels,

and adversely affecting native wildlife. As a project design feature, no invasive plant species would

be utilized in the landscaping plans, and no species on the Cal-IPC “Invasive Plant Inventory” list shall

be included in the erosion control plan. These design features are included in Table 2. Therefore

impacts would be less than significant.

Nuisance Animal Species − Domesticated animals, particularly cats, are known to impact native

wildlife in the habitat areas immediately adjacent to development. The proposed project has the

potential to result in introduction of domestic animals to the surrounding habitat. Project fencing

and the maintenance of healthy predator populations (coyote and bobcat) will minimize

introduction of domestic animals. Brown-headed cowbirds are an invasive nest parasite that can

greatly reduce the breeding success of native birds. This species has been reported on site and on

the adjacent property to the west in low numbers, and the proposed project is not expected to

significantly increase the number of brown-headed cowbirds in the surrounding habitat. In addition,

residential uses may introduce Argentine ants to local habitats, which could have significant

consequences for native ant species and animals that feed on them. Impacts from Argentine ants

will be avoided by requiring the inspection of all plant material prior to use on the site. This

requirement is identified as a project design features (Table 2). Therefore, impacts associated with

nuisance animal species are expected to be adverse but less than significant.

Night Lighting − Night lighting exposes wildlife species to an unnatural light regime and may alter

their behavior patterns, causing them to have lower reproductive success, and thus reducing species

diversity. All exterior lighting adjacent to preserved habitat including street lighting for Street A

shall be limited to low pressure sodium sources of the lowest illumination allowed for human safety,

selectively placed, shielded, and directed away from preserved habitat to the maximum extent

practicable. This requirement is identified as a project design features (Table 2). Therefore, impacts

due to night lighting would be considered less than significant.

Roadkill − Roadkill impacts would be considered significant if they resulted in adverse effects to

federally or state listed species. Roadkill could occur as vehicles travel on the internal roads



associated with the project. The primary drainage through the site may currently provide minimal

local wildlife movement through the project site, though the site is highly disturbed with mining

activities. The preserve over the southern portion of the site is completely avoided and connects

with offsite preserve areas, and the restored channel will include an arch culvert under the access

road to the proposed park to facilitate wildlife movement. Therefore, on-site roadkill impacts are

anticipated to be less than significant.

Noise − Noise from grading, grubbing, and vehicular traffic would be a temporary impact to local

wildlife. Noise impacts would be considered significant if sensitive species, such as the coastal

California gnatcatcher or raptor species were displaced and failed to breed. Breeding mammals and

birds may temporarily leave the project vicinity during construction activities; however, they would

be expected to return afterward once the noise impact has been eliminated because the habitat will

remain in place and viable for reoccupation by the displaced species. Noise levels during grading at

the grading/open space interface throughout the site would be in excess of 60 dBA Leq. Such noise

impacts to nesting coastal California gnatcatchers would be considered significant (Impact BIO-4).

Implementation of mitigation measures MM-BIO-4, which will be required as a condition of project

approval will reduce this potential impact to below a level of significance.

MM-BIO-4 If project grading (other than clearing and grubbing of sensitive habitats) is

necessary and adjacent to preserved on-site habitat during the bird breeding season

(February 15 to August 31), a qualified biologist shall conduct pre-construction

surveys in the adjacent habitat for the coastal California gnatcatcher\ and nesting

raptors. The survey shall begin not more than three days prior to the beginning of

grading activities. The Wildlife Agencies shall be notified if the gnatcatcher is

observed nesting within 300 feet of proposed grading or if raptors are observed

nesting within 500 feet of proposed grading activities. No activities which would

result in noise levels exceeding 60 dBA hourly Leq within this buffer shall be allowed.

If grading activities are not initiated prior to the breeding season, and any of these

species are present, and noise levels exceed this threshold, noise barriers shall be

erected to reduce noise impacts to occupied habitat to below 60 dBA hourly Leq

and/or the activities shall be suspended. Impacts resulting from noise for non-listed

species other than raptors are not considered significant, and mitigation is not

warranted.

b) Have a substantial adverse effect on any riparian habitat or other sensitive natural community

identified in local or regional plans, policies, regulations, or by the California Department of

Fish and Game or U.S. Fish and Wildlife Service? Less Than Significant with Mitigation

Incorporated

Direct Impact to Riparian Habitats

Implementation of the proposed project would result in impacts to wetland resources, including

0.23 acre of southern riparian forest, 0.15 acre of riparian woodland, 1.43 acre of southern willow

scrub, 0.16 acre of freshwater marsh (SWS/FWM), 0.33 acre of mule fat scrub, and 0.09 acre of

southern willow scrub/freshwater marsh habitat, 0.85 acre of disturbed wetland, as well as 0.02

acre of streambed, and 0.19 acre detention basin (Table 7b). These impacts are considered

significant (Impact BIO-5).



Table 7b. Summary of Impact to Vegetation Communities

Vegetation Community

Existing

(acres)

Impacts

(acres)

Proposed

HLP Preserve

(acres)

Southern riparian woodland (62000) 0.15 0.15 0.0

Southern riparian forest (61300) 1.72 0.23 0.70(1)

Southern willow scrub (63320) 1.43 1.43 0.0

Southern willow scrub/Freshwater Marsh

(63320/52400) 0.09 0.09 0.0

Mule fat scrub (63310) 0.33 0.33 0.0

Freshwater marsh (52400) 0.90 0.16 0.0

Disturbed wetland (11200) 0.85 0.85 0.0

Open water (13100) 1.56 0.0 0.0

Streambed 0.02 0.02 0.0

Diegan coastal sage scrub (32500) 92.6 0.0 91.4

Southern mixed chaparral (37120) 11.5 0.0 11.5

Eucalyptus woodland (79000) 7.9 5.4 3.2

Disturbed habitat (11300) 132.0 86.9 3.4

Detention basin (12000) 0.2 0.2 0.0

Total 251.2 95.7 110.0(2)

Notes:

(1) Does not include 1.0 acres that will also be preserved within the riparian mitigation area.

(2) Does not include additional acres conserved as part of wetland restoration onsite.

Implementation of mitigation measures MM-BIO-1A and MM-BIO-1B would reduce impact to

riparian habitats to below a level of significance since it would create and enhance riparian habitats

both on and offsite.

Direct Impact to Upland Habitat

No sensitive upland habitat impacts are anticipated. All sensitive upland habitats are located within

the existing HLP preserve area. Minor adjustments to the HLP preserve are proposed but there are

no impacts associated with the adjustment other than to disturbed habitat. These impacts are not

considered significant.

Indirect Impact to Sensitive Habitats

Indirect impacts that may be caused by implementation of the proposed project are associated with

edge effects. Edge effects occur when disturbance, development, or grading traverse an

undeveloped area with substantial native lands surrounding the impact area. Edge effects for

sensitive habitats include decreased water quality and temporary indirect impacts due to noise and

fugitive dust.

Water Quality – Landscaping often results in increased runoff, which could in turn reduce water

quality in riparian areas. The use of petroleum products (i.e., fuels, oils, lubricants) and erosion of

land cleared during mine reclamation could potentially contaminate surface water, adversely

affecting vegetation, aquatic animals, and terrestrial wildlife. However, implementation of BMPs

per the City’s grading permitting requirements, as well as installation of drainage and desiltation



basins outlined in the Stormwater Management Plan would reduce potential short-term water

quality impacts to below a level of significance. These requirements are included as project design

features (Table 2).

During construction, measures would be implemented as part of the project to control erosion,

sedimentation, and pollution that could impact water resources on and off site. Prior to the

commencement of grading, a Notice of Intent must be filed with the RWQCB for a National Pollutant

Discharge Elimination System General Construction Storm Water Permit. Specific permit

requirements include implementation of an approved Storm Water Pollution Prevention Plan, which

requires best management practices for erosion and sediment control related to construction

activities. Standard measures that may apply to the proposed project include:

• Surface drainage will be designed to collect and move runoff into adequately sized drainage

structures before being discharged into natural stream channels.

• Erosion control measures associated with the project will include techniques for both long-

and short-term erosion hazards. These include such measures as the short-term use of

gravel bags, matting, mulches, berms, hay bales, or similar devices along all pertinent

graded areas to minimize sediment transport.

• Native vegetation will be preserved whenever feasible, and all disturbed areas will be

stabilized as soon as possible after completion of grading.

• Use of energy dissipating structures (e.g., detention ponds, riprap, or drop structures) will

be used at storm drain outlets, drainage crossings, and/or downstream of all culverts, pipe

outlets, and brow ditches to reduce velocity and prevent erosion.

• A maintenance plan for temporary erosion control facilities will be established. This

typically involves inspection, cleaning, and repair operations being conducted after runoff-

producing rainfall.

• Removal and disposal of ground water (if any) encountered during construction activities

will be coordinated with the RWQCB to ensure proper disposal methods and locations under

a General Dewatering Permit if required. This may involve specific measures such as

removing excess sediment (through the use of desilting basins, etc.) and limiting discharge

velocity.

• Specified fueling and maintenance procedures will be designated to preclude the discharge

of hazardous materials used during construction (e.g., fuels, lubricants, and solvents). Such

designations will include specific measures to preclude spill including proper handling and

disposal techniques.

Further, the project shall comply with the latest NPDES permit (Order No. R9-2013-0001) as well as

the latest City of San Marcos’ Storm Water Standards Manual Guidelines. A WQIP shall be approved

by the City prior to issuance of any grading permit and shall address how the pollutants of concern

will be treated, how low impact development standards will be satisfied and how hydromodification

requirements will be achieved. .

Fugitive Dust – Dust released during grading activities could cover vegetation in adjacent habitat

areas. The resulting dust-induced shading could reduce native plant productivity, in turn displacing

native vegetation, reducing diversity, encouraging weed invasion, adversely affecting wildlife, and



increasing fire susceptibility. One of the project design measures requires that the monitoring

biologist periodically monitor adjacent habitats for excessive amounts of dust, and recommend

remedial measures to address dust control if necessary. This requirement is included as a project

design feature (Table 2). As a result, the effects of dust on surrounding vegetation are considered

less than significant.

c) Have a substantial adverse effect on federally protected wetlands as defined by Section 404 of

the Clean Water Act (including, but not limited to, marsh, vernal pool, coastal, etc.) through

direct removal, filling, hydrological interruption, or other means? Less Than Significant with

Mitigation Incorporated

A delineation of on-site jurisdictional areas was performed by HELIX in 2012. All areas with

depressions, drainage channels, or wetland vegetation were evaluated for the presence of U.S.

Army Corps of Engineers (USACE) and California Department of Fish and Wildlife (CDFW)

jurisdictional wetlands, as well as Waters of the U.S. (WUS) and CDFW streambeds in accordance

with applicable guidelines.

Within the study area, USACE jurisdictional areas occur along the primary drainage along the

eastern boundary and in the northern portion of the site. Additional jurisdictional areas occur in the

south-central portion of the site. Federal (USACE) jurisdictional areas on the project site include

1.39 acres of wetland and 0.46 acre of non-wetland WUS. See Figure 6 in Biological Technical Report

(Appendix C of this document) for the location of the USACE jurisdictional areas. State (CDFW)

jurisdictional areas on the project site include 4.83 acres of wetland and 0.07 acre of non-wetland

See Figure 7 in Biological Technical Report (Appendix C of this document) for the location of the

CDFW jurisdictional areas.

The project would cause permanent and temporary impacts to both USACE and CDFW jurisdictional

areas. The project would permanently impacts to 1.32 acre of USACE jurisdictional areas and 3.45

acres of CDFW jurisdictional areas (Table 8). See Figures 10 and 11 in Biological Technical Report

(Appendix C of this document) for the location of the impact areas. This represents a significant

impact (Impact BIO-6).

Impacts to all on-site WUS (including wetlands) are regulated by the USACE under Section 404 of the

Clean Water Act (33 USC 1344) and would require a USACE permit. Implementation of the project

will result in impacts greater than 0.5 acre and an Individual Permit would be necessary. Individual

permits require a biological assessment, a detailed Section 404(b) alternatives analysis, an

environmental assessment, and preparation of a mitigation and monitoring plan. A State Water

Resources Control Board (SWRCB) permit (401 Certification) is required under the Clean Water Act

in association with the 404 Permit.

The CDFW is also responsible for issuing permits for impacts to streambeds and wetlands under its

jurisdiction. Any impacts to CDFW jurisdictional areas are regulated under California Fish and Game

Code Section 1602 and will require a Streambed/Lake Alteration Agreement.



Table 8. USACE and CDFW Jurisdictional Impacts

Vegetated Habitat1

Habitat USACE2 CDFW

2

Southern riparian woodland 0.0 0.15

Southern riparian forest 0.05 0.23

Southern willow scrub 0.12 1.43

Southern willow scrub/freshwater marsh 0.09 0.09

Freshwater marsh 0.16 0.16

Mule fat scrub 0.02 0.33

Disturbed wetland 0.43 0.89

Subtotal 0.87 3.28

Unvegetated Habitat

Habitat USACE CDFW

Streambed 0.38 0.10

Detention Basin 0.07 0.07

Subtotal 0.45 0.17

TOTAL 1.32 3.45

Notes: 1Acreage is rounded to the nearest hundredth.

2All impacts are permanent. There are no temporary impacts.

The USACE and CDFW all require no net loss of wetlands, a policy under which mitigation occurs at a

minimum ratio of 1:1 with a combination of creation and restoration. The project includes relocating

the primary drainage to the west of the existing location, creating a widened channel bottom and

manufactured earthen slopes along both sides. Riparian vegetation is to be installed in the channel

bottom; the riparian edge will be planted with coast live oak woodland and the slopes are to be

planted with Diegan coastal sage scrub vegetation. Implementation of mitigation measures MM-

BIO-1A and MM-BIO-1B would reduce impact to jurisdictional habitat and unvegetated waters to

below a level of significance since it would create and enhance riparian habitats both on and offsite

and offset impacts to jurisdictional wetland and waters.

d) Interfere substantially with the movement of any native resident or migratory fish or wildlife

species or with established native resident or migratory wildlife corridors, or impede the use

of native wildlife nursery sites? Less than Significant Impact

The northern and eastern portions of the site are highly disturbed by previous mining activities and

do not function as local wildlife corridors. The native habitat in the southwestern portion of the site

provides live in habitat for wildlife and may also serve as a local corridor along the drainage in the

south-central portion of the site. The primary drainage is within the eastern and north-central

portion of the site, and originates from runoff from South Twin Oaks Valley Road, as well as recent

development east of Twin Oaks Valley Road. The runoff flows westerly through the property and

into Discovery Lake, which is situated immediately off site to the west. The onsite drainage has

been heavily degraded by the quarry operation over the years. Wildlife movement is most likely to

occur to and from the western portion of the site to the undeveloped lands to the west, east and

south. There are no regional corridors that traverse the site and the project lies outside of the

Biological Resource Conservation Area for the Multiple Habitat Conservation Plan. Regional

connectivity occurs to the south of the project.



The proposed open space occurs in the southwestern portion of the site and abuts existing open

space to the southwest and South Lake to the south. The small block of open space in the southern

corner of the site also is adjacent to existing open space located on the other side of Twin Oaks

Valley Road. Proposed restoration of the creek through the project will connect preserve lands in

the southwestern portion of the site with Discovery Lake immediately northwest of the site. The

drainage will maintain wildlife connectivity through these areas by providing a restored creek

channel with riparian habitat and upland buffer habitat, and by providing an arch culvert for wildlife

movement under the access road to the proposed park. Because the site is currently heavily

disturbed, wildlife movement may actually be enhanced along the creek channel. The

approximately 11 acres of open space along the restored creek channel will add to the regional

preserve in this area. Therefore impacts to regional conservation or wildlife movement are

anticipated and impact would be less than significant.

e) Conflict with any local policies or ordinances protecting biological resources, such as a tree

preservation policy or ordinance? No Impact

The proposed project would not conflict with any local policies or ordinances protection biological

resources, such as a tree preservation policies or ordinance. The project meets the requirements of

the existing HLP for the project site and includes habitat conservation as well as habitat creation and

enhancement. No impact is identified for this issue area.

f) Conflict with the provisions of an adopted Habitat Conservation Plan, Natural Community

Conservation Plan, or other approved local, regional, or state habitat conservation plan? No

Impact

The project site is located outside of the Biological Resource Conservation Area for the Multiple

Habitat Conservation Plan. Therefore the project would not conflict with the provisions of an

adopted Habitat Conservation Plan, Natural Community Conservation Plan, or other approved local,

regional, or state habitat conservation plan and no impact is identified.

V. CULTURAL RESOURCES

A Cultural Resources Report was prepared for the project by ASM Affiliates (2013) and is included in

Appendix D.

a) Cause a substantial adverse change in the significance of a historical resource as defined in

§15064.5? No Impact

A cultural resources report has been prepared for the project site by ASM Affiliates (2013) and is

included in Appendix D. The report presents the results of a cultural and historical resources

inventory conducted within the Area of Potential Effect for the proposed project. Site records on file

at the South Coastal Information Center (SCIC), San Diego State University, indicate 21 previous

archaeological surveys have been conducted within the one-mile search radius of the proposed

project. The report concluded that no cultural resources had been previously recorded within the

APE, and no new resources were recorded during the survey. No cultural resources have been

previously recorded within the search radius. Additionally, the pedestrian survey conducted by ASM

did not identify any historical resources on the site. Therefore, no impact is identified for this issue

area.



b) Cause a substantial adverse change in the significance of an archaeological resource pursuant

to §15064.5? Less Than Significant with Mitigation Incorporated

Based upon the cultural resources reports prepared for the project (ASM Affiliates 2013), no

archeological resources are known to occur on the project site. ASM’s research included a records

research and site reconnaissance.

Site records on file at the SCIC indicated 21 previous archaeological surveys have been conducted

within a one-mile radius of the proposed project. None of the previous surveys identified or

recorded archaeological resources within the current project boundary. Additionally, the pedestrian

survey conducted by ASM did not identify any historical resources on the site. A Sacred Lands File

Search was conducted by the Native American Heritage Commission (NAHC) and did not identify any

sacred sites in the project area).

Although ASM did not identify the potential for archeological or Native American resources, one of

the tribes (Rincon Band) consulted during the preparation of the Cultural Resources Analysis for the

proposed project, did note the potential to encounter unidentified resources during the grading

activities and requested that monitoring be conducted during the grading operation (Impact CR-1).

Correspondence from the Pala Band was received but noted that the project site was outside their

Traditional Use Area. Correspondence from the San Luis Rey Band requested a copy of the cultural

resources report once it was completed.

As the City does not have access to all tribal sacred land site records, the City will include as a

component of the project activities the presence of an Archeological monitor and a Native American

monitor during the earth moving grading activities to assure that any resources found during project

grading would be protected as directed by the Most Likely Decedent (MLD). Therefore, impacts are

less than significant with incorporation of mitigation measure MM-CR-1 through MR-CR-8.

Implementation of MM-CR-1 through MM-CR-8 shall be required as a condition of project approval

and will reduce potential impacts to below a level of significance.

MM-CR-1 An archeological monitor and a Luiseño Native American monitor shall be present

during the all earth moving and grading activities to assure that any potential

cultural resources, including tribal, found during project grading be protected.



activities in an effort to identify any unknown archaeological resources. Any newly

discovered cultural resource deposits shall be subject to cultural resources

evaluation, which shall include archaeological documentation, analysis and report

generation.

MM-CR-3 At least 30 days prior to beginning project construction, the Project Applicant shall

enter into a Cultural Resource Treatment and Monitoring Agreement (also known as

a pre-excavation agreement) with a Luiseño Tribe. contact the Rincon Tribe to

notify the Tribe of grading, excavation and the monitoring program and to develop a

Cultural Resources Treatment and Monitoring Agreement. The Agreement shall

address the treatment of known cultural resources, the designation, responsibilities,

and participation of professional Native American Tribal monitors during grading,



excavation and ground disturbing activities; project grading and development

scheduling; terms of compensation for the monitors; and treatment and final

disposition of any cultural resources, sacred sites, and human remains discovered

on site.

MM-CR-4 Prior to beginning project construction, the Project Archaeologist shall file a pre-

grading report with the City to document the proposed methodology for grading

activity observation, which will be determined in consultation with the Luiseño Tribe

referenced in MM-CR-3. the Rincon Tribe. Said methodology shall include the

requirement for a qualified archaeological monitor to be present and to have the

authority to stop and redirect grading activities. In accordance with the agreement

required in MM-CR-3, the archaeological monitor’s authority to stop and redirect

grading will be exercised in consultation with the Luiseño Native American monitor

the Rincon Tribe in order to evaluate the significance of any archaeological

resources discovered on the property. Tribal and archaeological monitors shall be

allowed to monitor all grading, excavation, and groundbreaking activities, and shall

also have the authority to stop and redirect grading activities.

MM-CR-5 The landowner shall relinquish ownership of all cultural resources, including sacred

items, burial goods, and all archaeological artifacts that are found on the project

area collected during the grading monitoring program and from any previous

archaeological studies or excavations on the project site to the appropriate Tribe for

proper treatment and disposition per the Cultural Resource Treatment and

Monitoring Agreement referenced in MM-CR-3. All cultural materials that are

deemed by the Tribe to be associated with burial and/or funerary goods will be

repatriated to the Most Likely Descendant as determined by the Native American

Heritage Commission per California Public Resources Code Section 5097.98.


conducted by an approved facility and the curation shalll be guided by California

State Historic Resource Commissions Guidelines for the Curation of Archaeological

Collections. The City of San Marcos shall provide the developer final curation

language and guidance on the project grading plans prior to issuance of the grading

permit, if applicable, during project construction.

collected during the grading monitoring program and from any previous

archaeological studies or excavations on the project site, with the exception of

sacred items, burial goods, and human remains which will be addressed in the

Treatment Agreement required in MM-CR-3, shall be tribally curated according to

the current professional repository standards by the Rincon Tribe. The collections

and associated records shall be transferred, including title, to the Rincon Tribe.





Coroner has made the necessary findings as to origin. Further, pursuant to California



Public Resources Code Section 5097.98(b) remains shall be left in place and free

from disturbance until a final decision as to the treatment and disposition has been

made. Suspected Native American remains shall be examined in the field and kept in

a secure location at the site If the San Diego County Coroner determines the

remains to be Native American, the Native American Heritage Commission (NAHC)

must be contacted within 24 hours. The NAHC must them immediately notify the

“most likely descendant(s)” of receiving notification of the discovery. The most likely

descendants(s) shall then make recommendations within 48 hours, and engage in

consultation concerning treatment of remains as provided in Public Resources Code

5097.98, and the Treatment Agreement described in MM-CR-.3.




assess the significance of such resources and shall meet and confer regarding the

mitigation for such resources. Pursuant to California Public Resources Code Section

21083.2(b) avoidance is the preferred method of preservation for archaeological

resources. If the Developer, the project archaeologist and the Tribe cannot agree on

the significance of mitigation for such resources, these issues will be presented to

the Planning Director for decision. The Planning Director shall make a determination

based upon the provisions of the California Environmental Quality Act with respect

to archaeological resources and shall take into account the religious beliefs,

customs, and practices of the Tribe. Notwithstanding any other rights available

under law, the decision of the Planning Director shall be appealable to the Planning

Commission and/or City Council.

c) Directly or indirectly destroy a unique paleontological resource or site or unique geologic

feature? Less Than Significant Impact

The project area is located in the Peninsular Ranges Geomorphic Province, underlain by Santiago

Peak Volcanics. In general, the molten origin of the Santiago Peak Volcanics precludes the discovery

of fossil remains. Therefore, due to the limited availability of fossil-producing geologic formations,

impacts due to this issue area are considered less than significant.

d) Disturb any human remains, including those interred outside of formal cemeteries? Less Than

Significant With Mitigation Incorporated

The cultural resource assessment prepared by ASM Affiliates (2013) did not indicate the likelihood

of human remains on the site. Additionally, existing regulations, through California Health and

Safety Code Section 7050.5 state that if human remains are discovered during project construction,

no further disturbance shall occur until the San Diego County Coroner has made the necessary

findings as to origin. Further, pursuant to California Public Resources Code Section 5097.98(b)

remains shall be left in place and free from disturbance until a final decision as to the treatment and

disposition has been made. If the San Diego County Coroner determines the remains to be Native

American, the Native American Heritage Commission shall be contacted within a reasonable

timeframe. Subsequently, the Native American Heritage Commission shall identify the “most likely

descendant.” The Most Likely Descendant shall then make recommendations, and engage in

consultations concerning the treatment of the remains as provided in Public Resources Code



5097.98. So, while the cultural resources assessment concluded that there is no evidence of human

remains on the project site, a Sacred Lands monitor shall be present during the earth moving

grading activities to assure that any resources found during project grading would be protected as

directed by the MLD. Therefore, impacts are less than significant with incorporation of mitigation

measures MM-CR-1 through MM-CR-8.

VI. GEOLOGY AND SOILS

a) Expose people or structures to potential substantial adverse effects, including the risk of loss,

injury, or death involving:

i) Rupture of a known earthquake fault, as delineated on the most recent Alquist-Priolo

Earthquake Fault Zoning map, issued by the State Geologist for the area or based on other

substantial evidence of a known fault? Refer to Division of Mines and Geology Special

Publication 42. No Impact

The project site is located within a seismically active region, as is all of Southern California.

However, the project site is not adjacent to any known active faults. The project site is not

located on a fault, as delineated by the most recent Alquist-Priolo Earthquake Fault Zoning Map

(Department of Conservation, 2008). The closest major active faults are the Elsinore fault,

located 15 miles to the northeast, and the Coronado Banks fault located offshore approximately

25 miles to the southwest. The Rose Canyon fault, which is potentially active, is located

approximately 11 miles southwest of the project site. Therefore, no impact is identified for this

issue area.

ii) Strong seismic ground shaking? Less Than Significant Impact

The proposed project is located in seismically-active Southern California and is considered likely

to be subjected to strong ground motion from regional seismic activity. As identified in Section

VI.a.i, the nearest identified potentially active fault is located approximately 11 miles from the

project area. All structures on the site would be designed in accordance with seismic parameters

of the California Building Code (2007). Therefore, the impact for this issue area would be

considered less than significant.

iii) Seismic-related ground failure, including liquefaction? No Impact

The project site is located within the coastal sub-province of the Peninsular Ranges Geomorphic

Province, and is underlain by metavolcanic rock of the Cretaceous to Jurassic-aged Santiago

Peak Volcanics. Leighton Consulting (2012) (Appendix E) conducted a limited geotechnical

exploration for the proposed San Marcos Elementary School at Rancho Coronado project

located in San Marcos, California. Based on the results of this exploration, the report concluded

that the proposed site improvements are feasible provided the geotechnical recommendations

contained in this report are implemented during design and construction (Impact GS-1).

Therefore, the impacts due to ground failure and liquefaction are considered less that

significant.

iv) Landslides? Less Than Significant Impact

Land sliding and slope instability in San Marcos is associated with bedding plane faults, weak



claystone and siltstone beds associated with Eocene sedimentary rocks. The community plan

areas of Barham/Discovery and Questhaven/La Costa Meadows have scattered sites known for

slope instability in hillside areas, however the project area consists of Exchequer series of soils.

These soils are formed in material weathered from hard metabasic rock, consisting of shallow to

very shallow, well-drained silt loams, located on mountainous uplands, and are not conducive to

landslides. In addition, on December 2, 2011, the reclamation plan submitted by Hanson was

approved for construction and a grading permit was issued on December 7, 2011. The grading

work took place between February and April 2012 on the proposed school site has resulted in

the establishment of stabilized 2:1 slopes or less. Therefore, no impact is identified for this issue

area.

b) Result in substantial soil erosion or the loss of topsoil? Less than Significant Impact

On December 2, 2011, the reclamation plan submitted by Hanson was approved for construction

and a grading permit was issued on December 7, 2011. The General Construction Permit (GCP) that

will be required of the project and the existing General Industrial Permit (GIP) for the project site

require BMPs for sediment control and erosion during construction activities or activities conducted

under the SWPPP. These BMPs are required and will mitigate soil loss and erosion.

The grading work took place between February and April 2012 and resulted in the establishment of

stabilized 2:1 slopes or less.

The project would be required to be under the GCP which requires the preparation of a SWPPP and

development of BMPs for all phases of construction. The GCP would result in stabilization of all

graded areas prior to the completion of the graded portions of the project.

The project would grade portions of the site and prepare the site for development of the residential,

mixed-use non-residential and active park uses as well as supporting roadways and infrastructure.

Grading operations could have the potential to expose bare slopes which could result in soil erosion

and loss of topsoil. However, the project would be required by the SWRCB GCP to obtaining

stabilization and incorporate erosion and sediment control measures during and after grading

operations. See Table 2 for a list of project design feature BMPs related to this topic. These BMPs

will be included in the SWPPP and in the construction plans and specifications which and shall be

implemented during construction. The GCP prohibits sediment or pollutant release from the project

site. Further all slopes will be required to be stabilized with permanent vegetation. Therefore,


c) Be located on a geologic unit or soil that is unstable, or that would become unstable as a

result of the project, and potentially result in on- or off-site landslide, lateral spreading,

subsidence, liquefaction or collapse? Less than Significant Impact

See comments VI.a.1 and VI .a.2.

d) Be located on expansive soil, as defined in Table 18-1-B of the Uniform Building Code (1994),

creating substantial risks to life or property? Less Than Significant Impact

The Preliminary Geotechnical Report and Addendum prepared by Leighton Consulting (2012) found

that the onsite soils are expected to have a low to moderate expansion potential, but concluded



that the project is feasible. A final geotechnical analysis would be performed to determine the actual

expansion potential of finish grade soils and recommendations in light of proposed building designs.

The final geotechnical analysis would ensure that the site soils are properly prepared so that any

potential expansion issues would be remedied. Therefore, impacts would be less than significant.

e) Have soils capable of adequately supporting the use of septic tanks or alternative wastewater

disposal systems where sewers are not available for the disposal of wastewater? No Impact

The project does not propose any septic tanks or alternative wastewater disposal systems.

Therefore, no impact is identified for this issue area.

VII. GREENHOUSE GAS EMISSIONS

A global climate change assessment was prepared for the project by Scientific Resources Associated

(2014b). The complete report is included as Appendix F of this document.

a) Generate greenhouse gas emissions, either directly or indirectly, that may have a significant

impact on the environment? Less Than Significant Impact

Existing Greenhouse Gas Emissions (GHG)

The site has historically been used for extraction of aggregate materials. The project is located

within the southwestern portion of the Heart of the City Specific Plan. The project site property is

bounded by Twin Oaks Valley Road on the east, the Discovery Hills residential community on the

north, and undeveloped land on the west and south, in the Barham/Discovery Hills neighborhood.

In its past use for extraction of aggregate materials, the site was a source of GHG emissions from the

use of equipment to extract materials and truck traffic to transport materials from the site.

GHG emissions associated with the Rancho Coronado Specific Plan were estimated separately for

four categories of emissions: (1) construction; (2) energy use, including electricity and natural gas

usage; (3) water consumption; and (4) transportation. The analysis includes a baseline estimate

assuming Title 24-compliant buildings, which is considered business as usual for the proposed

Project. Emissions were estimated based on emission factors from the California Climate Action

Registry General Reporting Protocol (CCAP 2008). This inventory presents emissions based on

“business as usual” assumptions.

Construction GHG Emissions

Construction GHG emissions include emissions from heavy construction equipment, truck traffic,

and worker trips. Emissions were calculated based on the CalEEMod Model (ENVIRON 2011). Total

GHG emissions associated with construction are estimated at 7,245 metric tons of CO2e. To

evaluate construction projects’ contribution to overall annual GHG emissions, the SCAQMD

recommends in their interim guidance for evaluating GHGs under CEQA (SCAQMD 2008). For

construction emissions, the interim guidance recommends that the emissions be amortized over 30

years and added to operational emissions, as appropriate. Amortized over 30 years, construction

would contribute 240 metric tons per year of CO2 emissions.

Operational GHG Emissions



The proposed project includes 346 residential units, 24 acres of non-residential mixed use,

approximately 38 acres of active park and the necessary infrastructure to support the proposed

development. Total electricity, natural gas, and water usage rates for the residences and commercial

development under “business as usual” conditions were estimated as discussed in the sections

below.

Energy Use Emissions – As discussed above, energy use generates GHG through emissions from

power plants that generate electricity, as well as emissions from natural gas usage at the facility

itself.

Business as usual electricity use was estimated based on construction of the proposed Project to

meet the requirements of Title 24 as of 2005. As stated in Section 3.0, based on the latest

guidelines and baseline emission calculations for energy efficiency, “business as usual” is considered

to be the equivalent of Title 24 as of 2005 because the ARB’s baseline inventory and its definition of

business as usual is based on compliance with Title 24 as of 2005. The ARB prepared its inventory to

evaluate the required reduction from “business as usual,” which is defined as the baseline with no

measures implemented to reduce emissions of GHGs. For building standards, the goal of reducing

emissions below business as usual within the ARB’s Scoping Plan is based on Title 24 as of the ARB’s

inventory. Thus, the baseline used in this analysis is consistent with the ARB’s analysis and goals.

The use of Title 24 as of 2005 is consistent with the Scoping Plan. The Scoping Plan is the original

basis for the County’s approach to evaluating significance of impacts for GHG emissions. The County

based its goals for reduction of emissions from “business as usual” levels on the Scoping Plan. It is

therefore appropriate to use the baseline energy use contained in the Scoping Plan as the baseline

for evaluating emissions for individual projects within the County. As stated above, Title 24 as of

2005 was the baseline used in the ARB’s Scoping Plan.

Emissions were calculated based on emission factors in the California Climate Action Registry

General Reporting Protocol, Version 3.1 (CCAR 2009).

Natural gas use was also estimated based on construction of the proposed Project to meet the

requirements of Title 24 as of 2005. Emissions were calculated based on emission factors in the

California Climate Action Registry General Reporting Protocol, Version 3.1 (CCAR 2009).

Residential electricity use was estimated based on average performance for southern California

residences, according to the California Statewide Residential Appliance Saturation Survey (CEC

2004). The energy use figures in this report represent current state-wide average uses, including

those that are compliant with 2005 Title 24 standards. The California Statewide Residential

Appliance Saturation Survey provided estimated energy use of 7,605 kWh annually within California.

In the California Statewide Residential Applicant Saturation Survey, natural gas usage rate were

reported at 421 therms per year.

Water – Water use and energy use are often closely linked. The provision of potable water to

commercial users consumes large amounts of energy associated with five stages: source and

conveyance, treatment, distribution, end use, and wastewater treatment. This inventory estimated

that delivered water for the proposed Project will have an embodied energy of 0.0127 kWh/gallon.

Water usage was estimated based on the CalEEMod model annual estimates of 22,543,300 gallons

of indoor water use and 14,212,100 gallons of outdoor water use for the residences. The model

estimates 38,390,490 gallons of indoor water use and 23,529,655 gallons of outdoor water use for



the business park, and 1,777,741 gallons of indoor water use and 1,089,583 gallons of outdoor

water use for the retail uses. The embodied energy demand associated with this water use was

converted to GHG emissions with the same emission factors used in the CCAP as for purchased

electricity.

Transportation – Several regulatory initiatives have been passed to reduce emissions from on-road

vehicles, as discussed in Section 1.3. For the purpose of calculating “business as usual” emissions

associated with vehicles, no credit was taken for implementation of the CAFE standards, Pavley

standards, or the LCFS.

Vehicle emissions were calculated based on the average daily trips (ADT) for the project from the

Traffic Impact Analysis (RBF Consulting 2014). The analysis estimated the total number of trips for

the project to be 8,926. It was assumed that the average trip length would be 5.8 miles, based on

the SANDAG average trip length (SANDAG 2012).

GHG emissions under “business as usual” conditions are summarized in Table 9A. As shown in

Table 9A, total CO2e emissions would be 14,767 metric tons per year.

Table 9A. Summary of Estimated Operational GHG Emission – Business as Usual Scenario

Emission Source

Annual Emissions

(Metric tons/year)

CO2 CH4 N2O


Electricity Use Emissions 4,199 0.1751 0.0470

Natural Gas Use Emissions 900 0.1000 0.0017

Water Consumption Emissions 1,317 0.0549 0.0147

Vehicle Emissions 7,978 0.0579 0.3345

Amortized Construction Emissions 241 - -

Total 14,635 0.39 0.40

Global Warming Potential Factor 1 21 310

CO2 Equivalent Emissions 14,635 8 124

Total CO2 Equivalent Emissions 14,767

A significance threshold of 28.35% from “business as usual” levels is considered to demonstrate that

a project would be consistent with the goals of AB 32. If the proposed project can demonstrate that

it would meet these goals, its greenhouse gas emissions, emitted either directly or indirectly, would

not have a significant impact on the environment.

Not all of the GHG-reducing project design features identified above are quantifiable due to

scientific and methodological limitations regarding GHG savings. The CEC (Architectural Energy

Corporation 2007) estimates that implementation of the Title 24 standards as of 2008 will result in

reductions in electricity use of 22.7% for residential dwellings. The CEC also estimates that

implementation of the Title 24 standards as of 2008 will result in reductions in natural gas use of

7.4% for residential dwellings.



GHG emissions from water use would also be reduced through the use of on-site groundwater to

irrigate the park uses. Because the water used for the park uses would be groundwater, there

would be no energy use in the conveyance, treatment, and wastewater disposal from park uses.

The embodied energy for local water sources is estimated at 110 kWh/million gallon (Cooley and

Wilkinson 2012). It is anticipated that water conservation measures that will be implemented for

the development would reduce water consumption by 10 percent. These measures include the use

of low-flow fixtures, use of drought-resistance landscaping, and means to reduce water usage such

as irrigation systems that conserve water.

Implementation of the RPS will affect indirect GHG emissions associated with electricity use for the

project because electricity will be purchased from San Diego Gas and Electric. According to the

SDCGHGI, implementation of the 33 percent RPS mandate, as established by Senate Bill 107, would

reduce GHG emissions by 27 percent from 2005 levels; credit was taken for these GHG savings in

this analysis.

Implementation of the new Federal CAFE standards will achieve reductions that are equivalent to

those proposed in AB 1493, the Pavley bill. Emissions were calculated based on the 2020 emission

factors from the EMFAC2011 model (ARB 2011), with credit for the Pavley standards and the Low

Carbon Fuel Standard.

The results of the GHG inventory for emissions with implementation of GHG reduction measures are

presented in Table 9B.

Table 9B. Summary of Estimated Operational GHG Emission –

With GHG Reduction Measures Scenario

Emission Source

Annual Emissions

(Metric tons/year)

CO2 CH4 N2O


Electricity Use Emissions 2,267 0.0946 0.0254

Natural Gas Use Emissions 703 0.0782 0.0013

Water Consumption Emissions 584 0.0244 0.0065

Vehicle Emissions 5,826 0.0405 0.2676

Amortized Construction Emissions 241 - -

Total 9,621 0.24 0.30

Global Warming Potential Factor 1 21 310

CO2 Equivalent Emissions 9,621 5 93

TOTAL CO2 Equivalent Emissions 9,719

Business as Usual CO2 Equivalent Emissions 14,766

Percent Reduction from Business as Usual 34.19%

As shown in Table 9B, with implementation of the project design features, project emissions would

total 9,719 metric tons per year. This represents a 34.19 percent reduction in emissions over

“business as usual” levels. Thus, the project will have a less than significant impact with regard to



greenhouse gas emissions.

b) Conflict with any applicable plan, policy or regulation of an agency adopted for the purpose of

reducing the emissions of greenhouse gases? Less Than Significant Impact

As part of the General Plan, the City has adopted a Conservation and Open Space Element, which

includes a goal (Goal COS-4) to improve air quality and reduce GHG emissions within the City. As

part of the Conservation and Open Space Element, the City has adopted the following General Plan

Policies designed to achieve the goal of reducing GHG emissions:

• Policy COS-4.3: Participate in regional efforts to reduce greenhouse gas emissions.

• Policy COS-4.4: Quantify community-wide and municipal greenhouse gas (GHG) emissions,

set a reduction goal, identify and implement measures to reduce greenhouse gas emissions

as required by governing legislation.

• Policy COS-4.5: Encourage energy conservation and the use of alternative energy sources

within the community.

• Policy COS-4.6: Promote efficient use of energy and conservation of available resources in

the design, construction, maintenance and operation of public and private facilities,

infrastructure and equipment.

• Policy COS-4.7: As City facilities and services are constructed or upgraded, incorporate

energy and resource conservation standards and practices by:

o Taking a leadership role in implementing programs for energy and water

conservation, waste reduction, recycling and reuse and increased reliance on

renewable energy.

o Upgrading City buildings and infrastructure facilities to comply with State of

California green building standards.

o Implementing landscaping that reduces demands on potable water; this may include

the use of drought tolerant landscaping and/or use of well water for irrigation,

favoring recycling and energy-efficient products and practices when issuing City

purchase agreements.

• Policy COS-4.8: Encourage and support the generation, transmission and use of renewable

energy.

• Policy COS-4.9: Encourage use and retrofitting of existing buildings under Title 24 of the

California Building Energy Code.

As shown in Table 9B, with implementation of the project design features, project emissions would

total 9,719 metric tons per year. This represents a 34.19 percent reduction in emissions over

“business as usual” levels. Thus, the project will have a less than significant impact with regard to

greenhouse gas emissions and would not conflict with any applicable plan, policy or regulation of an

agency adopted for the purpose of reducing the emissions of greenhouse gases.



VIII. HAZARDS AND HAZARDOUS MATERIALS

A Phase I Environmental Site Assessment was prepared for the project (SCS Engineers, 2012) and is

included as Appendix G of this document. Additionally, a soil characterization report was prepared for

the project site by Geosyntec (2013) and is included as Appendix H of this document.

a) Create a significant hazard to the public or the environment through the routine transport,

use or disposal of hazardous materials? Less Than Significant Impact

Hazardous materials include solids, liquids, or gaseous materials that, because of their quantity,

concentration, or physical, chemical, or infectious characteristics, could pose a threat to human

health or the environment. Hazards include the risks associated with potential explosions, fires, or

release of hazardous substances in the event of an accident or natural disaster, which may cause or

contribute to an increase in mortality or serious illness, or pose substantial harm to human health or

the environment.

The proposed project would involve the transport of fuels, lubricants, and various other liquids

needed for operation of construction equipment at the site and would be transported to the

construction site on an as-needed basis by equipment service trucks. In addition, workers would

commute to the project site via private vehicles, and would operate construction

vehicles/equipment on both public and private streets. Materials hazardous to humans, wildlife, and

sensitive environments would be present during project construction of the pipeline installation.

These materials include diesel fuel, gasoline, equipment fluids, concrete, cleaning solutions and

solvents, lubricant oils, adhesives, human waste, and chemical toilets. The potential exists for direct

impacts to human health and biological resources from accidental spills of small amounts of

hazardous materials from construction equipment during construction of the pipeline; however, the

proposed project would be required to comply with Federal, State, and City Municipal Code

regulations which regulate and control those materials handled onsite. Compliance with these

restrictions and laws ensure that potentially significant impacts would not occur. Therefore, a less

than significant impact is identified.

b) Create a significant hazard to the public or the environment through reasonable foreseeable

upset and accident conditions involving the release of hazardous materials into the

environment? Less Than Significant Impact with Mitigation Incorporated

Phase 1 Environmental Site Assessment Results

A Phase 1 Environmental Site Assessment was prepared by SCS Engineers (2012). The assessment

concluded that there is a low likelihood that a recognized environmental condition exists at the site

as a result of the current or historical site land use or from known and reported off-site sources.

Soil Characterization Analysis Results

Portions of the project site were historically was used for aggregate mining and related activities.

Previous soil characterization activities conducted on the Hanson Property identified arsenic in soil

samples collected within a portion of the project site at concentrations above established

background levels, but the anomalous arsenic concentrations did not appear to be attributable to

historical operations on the Property or other anthropogenic activities. This area of the project site



is associated with the portion identified for future non-residential mixed-use development in the

southeastern portion of the project site.

In May 2012, Tetra Tech conducted an investigation of soil conditions within the area proposed for

future non-residential mixed-use development. Tetra Tech collected twenty-five soil samples from

seven boring locations (B1 through B7 to evaluate metals concentrations in areas where

“undocumented fill1” had been identified during a prior Phase I ESA and geotechnical investigation.

This undocumented fill is related to grading activities performed during the construction of the Twin

Oaks Valley Road just to the east of the site, and overburden material from onsite mining activities.

Soil sampling was performed under the direction of Tetra Tech using a direct-push rig. Fill soil was

reportedly encountered by Tetra Tech to depths up to approximately 18 feet below ground surface.

Each of the 25 soil samples was analyzed for total metals by EPA Method 6010B/7471A. Arsenic

concentrations in the soil samples ranged from 0.831 mg/kg to 72.2 mg/kg. The remaining metals

concentrations were within the typical range of background concentrations in San Diego soil. Tetra

Tech concluded that arsenic concentrations in soil samples collected at the site are “naturally-

occurring and within the ambient range…and that the arsenic is not an anomalous detection and

does not require further investigation.”

In August 2012, Geosyntec performed additional soil sampling which confirmed arsenic

concentrations in excess of the upper bound California background established by the Department

of Toxic Substances Control (12 mg/kg; DTSC, 2008) in soil localized to the vicinity of Tetra Tech

borings B-1, B-4, and B-5, and adequately delineated the extent of arsenic in soil in the vicinity of

those three borings.

In March 2013 Geosyntec prepared a report titled “Native Background Arsenic Summary” which

outlined the occurrence of naturally-occurring arsenic in San Diego County. The Santiago Peak

Volcanics Formation has historically been economically mined for arsenic in its mineral form as

arsenopyrite. Arsenopyrite, the sulfarsenide of iron, is a principal ore of arsenic. Arsenopyrite is

associated with high temperature hydrothermal veins, in pegmatities, and in areas of contact

metamorphism. Because the formation is volcanic in nature and that hydrothermal alteration in

veins and areas of contact metamorphisim have been identified throughout the formation,

arsenopyrite is associated with the formation and at one time an economically viable mineral

resource in San Diego County. From researching historical arsenic mining operations in San Diego

County located in the Santiago Peak Volcanics Formation, the mines were typically situated in

canyons or the saddles of ridges which are areas where preferential erosion is occurring and

exposing potentially significant arsenopyrite deposits. Veins, contact metamorphosed, and

hydrothermally altered rock tend to be more fractured or have mineralized zones that lead to areas

that are more susceptible to erosional forces. Two documented arsenic mines in San Diego County

that are located within the Santiago Peak Volcanic Formation are the Black Mountain Mine and

Cedar Creek Mine. The Property is underlain by the Santiago Peak Volcanics Formation, and there

are no known anthropogenic sources of arsenic on or near the project site.

Concentrations of arsenic from the samples collected in 2012 by Geosyntec ranged from 3.86 mg/kg

to 159 mg/kg. Geosyntec also collected ten soil samples a hand auger throughout the Hanson

property at depths of 0.5 to 3.0 ft. below ground surface to evaluate background concentrations of

arsenic in soil. The concentrations of arsenic in soil in the 10 background samples ranged from



4.78 mg/kg to 134 mg/kg. Data from the May and August 2012 soil investigations indicate that

arsenic concentrations are generally higher in the eastern portion of the analysis where the Santiago

Peak Volcanic formation is exposed at or near the existing ground surface, and in fill material in the

north-central portion of the analysis area that was derived from Santiago Peak Volcanics during

grading activities in the eastern portion of the area proposed for future non-residential mixed use

when Twin Oaks Valley Road was constructed in the period between 2004 and 2007.

Results from the previous investigation performed by Tetra Tech and recent investigation performed

by Geosyntec indicate that the majority of the soil samples which contained elevated concentrations

of naturally-occurring arsenic are localized in the area propose for future non-residential mixed use.

Statistical evaluations performed on the data demonstrated that the localized areas of naturally-

occurring elevated arsenic in soil can be effectively managed through soil management activities to

achieve a site that would be suitable for the proposed development.

The requirement for a soils management plan is included as mitigation measure MM-HAZ-1 and

implementation of this measure will be required as a condition of project approval.

MM-HAZ-1 Prior to grading activities, the project applicant shall prepare and implement a soils

management plan that addresses handling of soils containing naturally-occurring

arsenic during grading. The management plan shall be submitted to the City

Engineer for review and approval prior to the issuance of a grading permit.

c) Emit hazardous emissions or handle hazardous or acutely hazardous materials, substances, or

waste within one-quarter mile of an existing or proposed school? No Impact

There are no existing or proposed schools within 0.25 mile of the project site. Further, the project

does not propose uses that would emit hazardous emissions or handle hazardous or acutely

hazardous materials or substances. Therefore no impact is identified for this issue area.

d) Be located on a site which is included on a list of hazardous materials sites compiled pursuant

to Government code Section 65962.5 and, as a result, would it create a significant hazard to

the public or the environment? No Impact

The project site is not identified on a list of hazardous materials sites compiled pursuant to

government code Section 65962.5. Therefore no impact is identified for this issue area.

The California Department of Toxic Substances Control maintains an online database (EnvirStor) that

allows for search of permitted facilities and environmental cleanup activities at a specific location. A

review of EnviroStor revealed two entries associated with the project site. The first was associated

with the soil boring for background arscenic testing. The second listing was associated with a

previous project proposal on the site that included a school. Since the school is no longer proposed,

that listing is no longer active. The results of the arscenic testing were addressed in Section VIII(b),

above. No other listings were identified within a quarter-mile of the project site and no impact is

identified for this issue area.



e) For a project located within an airport land use plan or, where such a plan has not been

adopted, within two miles or a public airport or public use airport, would the project result in

a safety hazard for people residing or working in the project area? No Impact

The proposed project is not located within an airport land use plan area, nor is it within two

miles of a public airport or public use airport. The nearest is the McClellan-Palomar Airport in

Carlsbad, which is located approximately six miles west of the project area. The project site is

located outside the over-flight notification area, but is located within the Review Area 2 of the

airport influence area. The influence area is regulated by the Airport Land Use Commission

(ALUC), which regulates land uses in the area to be compatibility with airport-related noise,

safety, airspace protection, and over-flight factors. Review Area 2 consists of limits on heights

of structures in areas of high terrain. The project site would not be characterized as high terrain,

as it is situated south and east of higher terrain areas. Therefore, no impact is identified for this

issue area.

f) For a project within the vicinity of a private airstrip, would the project result in a safety hazard

for people residing or working in the project area? No Impact

The proposed project is not located within the vicinity of a private airstrip. Therefore the project

does not have the potential to result in a safety hazard for people residing or working in the project

area. No impact is identified for this issue area.

g) Impair implementation of or physically interfere with an adopted emergency response plan or

emergency evacuation plan? Less than Significant Impact

The project does not propose any development that would impair implementation of or physically

interfere with an adopted emergency response plan or evacuation plan. Construction of the project

would not result in any complete road closures. The San Marcos Fire Department has reviewed the

project and has not raised any concerns on this issue. Therefore, impacts are less than significant.

h) Expose people or structures to a significant risk of loss, injury or death involving wildland fires,

including where wildlands are adjacent to urbanized areas or where residences are intermixed

with wildlands? Less Than Significant Impact with Mitigation Incorporated

The project proposes development adjacent to natural areas which will be preserved as open space.

This creates and areas where development will be adjacent to wildland areas that have a high fire

risk. This represents a significant impact (Impact HAZ-2). Implementation of mitigation measures

MM-HAZ-2, which requires preparation and implementation of a Fire Protection Plan will reduce

this impact to below a level of significance.

MM-HAZ-2 Prior to issuance of building permits, a fire protection plan shall be prepared for the

project and submitted to the Planning Director and Fire Marshal for review and

approval. The fire protection plan shall include fire fuel clearing and fire fuel

management zones to provide a minimum 150-foot buffer between proposed

structures and natural habitat. The fire protection plan shall identify the responsible

parties for the ongoing fire fuel maintenance and the mechanism to ensure

compliance with fire clearing requirements. Implementation of the fire protection

plan shall be required prior project occupancy.



Thus implementation of mitigation measures MM-HAZ-2 will reduce the potential impact of

exposing people or structures to a significant loss, injury, or death involving wildland fires, would be

reduced to below a level of significance.

IX. HYDROLOGY AND WATER QUALITY

a) Violate any water quality standards or waste discharge requirements? Less than Significant

Impact

The project will comply with all water quality standards and waste discharge requirements. Since

the project includes disturbance to more than an acre, a Construction General Permit from SWRCB

will be require prior to the issuance of a grading permit. A Storm Water Pollution Prevention Plan

(SWPPP) will be developed and implemented in accordance with the appropriate Risk Level, as

determined by the City Engineer. The SWPPP will identify Best Management Practices (BMPs) to

protect storm water runoff.

New Regional MS4 Permit

On May 8, 2013, the SDRWQCB adopted Order R9 2013-0001, the new Regional MS4 Permit. The

permit became effective June 27, 2013. The City is required to update its SUSMP land development

requirements within three months of the SDRWQCB concurrence of the Carlsbad Watershed WQIP

which is estimated to be 24 months after the May 8, 2013 adoption of R9 2013-0001 or

approximately December 2015. The City will make project-specific determinations on a case-by-case

basis as to what constitutes prior lawful approval based on its Municipal Code, Ordinances, and

project milestones within the development process to identify the appropriate MS4 permit land

development requirements that are applicable to each project.

The proposed project has been designed to comply with the land development requirements of

Order R9 2007-001 and the City SUSMP (as amended January 14, 2011). Long term water quality and

HMP requirements are mitigated through appropriate design and mitigation requirements for

residential, parking lot, and street land uses.

The proposed project is on a development schedule to achieve prior lawful approval under the land

development requirements of R9 2007-0001 in accordance with the City’s municipal ordinances and

is therefore in compliance with the SDRWQCB MS4 permit at this time.

Prior to final issuance of construction permits, the City will evaluate the project’s land development

milestones and construction schedule and issue a Final Determination of Prior Lawful Approval and

determination of applicable MS4 Permit development requirements and MS4. The project will be

required to provide a design to mitigate water quality and HMP under the land development

requirements deemed to be in effect of either R9 2007-001 or R9 2013-0001.

At this time it is anticipated that no substantive changes will occur with project design based on the

recent adoption of R9 2013-0001and the projects development milestone schedule for construction

and implementation.

In summary, the proposed project will not violate any water quality standards or waste discharge

requirements. Impact will be less than significant.



b) Have a potentially significant adverse impact on groundwater quality or cause or contribute to

an exceedance of applicable groundwater receiving water quality objectives or degradation of

beneficial uses? No Impact

The project does not propose any uses or irrigation with groundwater or wells that would impact

ground water quality or cause or contribute to an exceedance of applicable groundwater receiving

water quality objectives or degradation of beneficial uses. The project proposes residential, mixed-

use non residential, active park, and habitat conservation. Therefore no impact is identified.

c) Substantially deplete groundwater supplies or interfere substantially with groundwater

recharge such that there would be a net deficit in aquifer volume or a lowering of the local

groundwater table level (e.g., the production rate of preexisting nearby wells would drop to a

level which would not support existing land uses or planned uses for which permits have been

granted)? No Impact

The proposed project will not use groundwater, thus the project would not result in the substantial

depletion of groundwater supplies or interfere substantially with groundwater recharge. Thus no

impact is identified for this issue area.

d) Substantially alter the existing drainage pattern of the site or area, including through the

alteration of the course of a stream or river, in a manner which would result in substantial

erosion or siltation on-or off-site (e.g. downstream)? Less than Significant Impact

This threshold is analyzed in terms of short term project construction impact and long term/project

operation impacts.

Short Term (Project Construction)

The project site is topographically diverse and has hill and valley areas. Existing elevations range

from a high of approximately 875 feet msl in the southeastern portion of the site to a low of

approximately 720 feet msl in the northern portion of the project site.

Grading would occur on the project site to prepare the site roadways, utility infrastructure,

residential pads, and future pads for the park and non-residential mixed use area. The project will

incorporate construction BMPs in compliance with the General Construction Permit. These BMPs

focus on areas such as good site management/housekeeping, non-stormwater management,

erosion control, sediment control, run-on and run-off control, inspection/maintenance/repair, rain

event action plan, and monitoring/reporting requirements. Implementation of these BMPs will

further reduce the potential for erosion and siltation entering waterways. Impact will be less than

significant.

Long Term (Project Operation)

The project will increase the area of impervious surface on the project site. However, based upon

the analysis prepared by Fuscoe Engineering (2013), runoff amounts and quantities would be similar

in the pre- and post-condition.



To provide water quality treatment and hydromodification mitigation of runoff from the project site

and tributary areas, the project was divided into drainage management areas (DMA), and one best

management practice (BMP) has been provided in each DMA to provide water quality treatment

and hydromodification mitigation. The BMPs used for the project are bioretention basins. The

following table shows the pre-development runoff in cubic feet per second (cfs) as well as the post-

development condition with and without the proposed low impacts development (LID) features.

Basin and Flow Condition

Peak Runoff (CFS) by Recurrence Interval

0.5Q2 Q2 Q5 Q10

BMP-3 Pre-Development .89 1.78 2.69 3.56

Post-Development

(Unmitigated) 1.31 2.63 3.43 4.71

Post-Development

(Mitigated) 0.44 0.87 1.42 1.79

BMP-5 Pre-Development 1.51 3.03 4.43 5.97

Post-Development

(Unmitigated) 2.40 4.79 6.27 8.60

Post-Development

(Mitigated) 1.33 2.66 3.61 4.61

BMP-7 Pre-Development 2.29 4.57 6.75 8.70

Post-Development

(Unmitigated) 3.14 6.27 8.14 11.15

Post-Development

(Mitigated) 1.41 2.83 4.19 4.89

Source: Fuscoe Engineering (2013)

As shown in the table, the post-development (mitigated) condition has runoff values that are below

the pre-development conditions. The project incorporates LID features and BMPs which minimize

the potential for erosion and siltation. The project conserves natural areas, soils and vegetation. The

project detains and retains runoff through the site through the use of bioretention features.

Bioretention will be used to achieve compliance with stormwater treatment requirements as well as

the LID requirements in the stormwater NPDES permit. Bio-retention was selected the LID to treat

the stormwater runoff project the project site. Impacts would be less than significant.

e) Create a significant adverse environmental impact to drainage patterns due to changes in

runoff flow rates or volumes? Less than Significant Impact

The project will increase the area of impervious surface on the project site due to the construction

of roads and structures. The WQIP assumed that for those areas proposed for development,

approximately 70 percent of the area would be impervious. The project will retain over 129 as

preserved open space.

Impervious surfaces can increase runoff flow rates and volumes; however the project has been

designed to maintain pre-condition runoff amounts and quantities on the project site, as discussed

in threshold IX.d, above. Runoff rates and volumes in the post-development condition will be less

than the pre-development condition when BMPs and LID requirements are considered. Thus the

project would not result in a significant adverse environmental impact to drainage patterns due to

change in runoff rates or volumes and impacts are less than significant.



f) Substantially alter the existing drainage pattern of the site or area, including through the

alteration of the course of a stream or river, or substantially increase the rate or amount of

surface runoff in a manner, which would result in flooding on-or off-site? Less than Significant

Impact

The project is still adequately designed such that the project would not substantially alter the

existing drainage pattern of the site or area, including through the alteration of the course of a

stream or river, or substantially increase the rate or amount of surface runoff in a manner which

would result in flooding on or off site.

Runoff rates and volumes in the post-development condition will be less than the pre-development

condition when BMPs and LID requirements are considered. Thus the project would not result in a

significant adverse environmental impact to drainage patterns due to change in runoff rates or

volumes and impacts are less than significant.

There are no streams or rivers on the project site, though there are wetland/riparian areas that have

been created through runoff. These areas will be enhanced and restored as part of the proposed

project’s mitigation for impacts to biological resources.

g) Create or contribute runoff water which would exceed the capacity of existing or planned

storm water drainage systems or provide substantial additional sources of polluted runoff?


The project proposes a comprehensive stormwater management plan that includes stormwater

improvements within the project boundary. This includes bio-retention ponds that will detain and

retain stormwater flows from the pads and roadways. Construction of these facilities is proposed

within the development footprint for the project. An expansion of existing facilities will not be

required to serve the project. Thus impacts would be less than significant.

h) Result in increased impervious surfaces and associated increased runoff? Less than Significant

Impact

The project will increase the area of impervious surface on the project site due to the construction

of roads and structures. The WQIP assumed that for those areas proposed for development,

approximately 70 percent of the area would be impervious. The project will retain over 129 as

preserved open space.

Impervious surfaces can increase runoff flow rates and volumes; however the project has been

designed to maintain pre-condition runoff amounts and quantities on the project site, as discussed

in threshold IX.d, above. Runoff rates and volumes in the post-development condition will be less

than the pre-development condition when BMPs and LID requirements are considered. Thus the

project would not result in a significant adverse environmental impact related to an increase in

impervious surfaces and impacts are less than significant.



i) Result in significant alteration of receiving water quality during or following construction? Less

than Significant Impact

The analysis of this threshold considers both short term and long term water quality. Potential

construction-related impacts associated with receiving water quality would include siltation and

erosion, the use of fuels for construction equipment, and the generation of trash and debris from

the construction site. Project design feature have been identified that will minimize these potential

for construction-related water quality impacts.

Short Term

The project will incorporate construction-related water quality BMPs to protect water quality. Such

measures could include, but are not limited to:

• Use of sediment trapping devices to control sediment runoff;

• Proper containment and disposal of trash/debris;

• Use of erosion control devices to minimize runoff during rain events; and

• Additional measures to be identified once SWPPP is available prior to the issuance of the

grading permit and start of work onsite

These measures are designed to minimize the generation of pollutants, including sediment,

trash/debris, and erosion. Preparation and implementation of a SWPPP and construction-related

water quality BMPs will ensure that there are no significant alterations to receiving water quality

during construction. Impacts would be less than significant.

Long Term (Project Operation)

With regard to project operation, the project includes a comprehensive water quality management

approach. The complete WQIP is included as Appendix I. The project proposes the comprehensive

use of bio retention and filtration Additionally, the project will implement a variety of site design,

source control, LID, and treatment control BMPs in accordance with Order R9 2007-001 to treat to a

medium pollutant removal rate or better for the pollutants of concern (nutrients and bacteria) and

minimize the potential for pollutants such as sediment, trash, metals, bacteria, oil/grease and

organics prior to reaching the storm drain and off-site waterways. The project is required to

integrate into its design site design, source control, LID, and treatment control BMPs in accordance

to R9 2007-0001 or R9 2013-0001. Thus the project will would not result in significant alterations to

receiving water quality after construction and impacts are less than significant.

j) Result in an increase in pollutant discharges to receiving waters? Consider water quality

parameters such as temperature, dissolved oxygen, turbidity and other typical storm water

pollutants (e.g. heavy metals, pathogens, petroleum derivatives, synthetic organics, sediment,

nutrients, oxygen-demanding substances, and trash). Less than Significant Impact

The project site is located in the Richland (904.52) hydrologic sub-area of the San Marcos (904.5)

hydrologic area of the Carlsbad watershed. Impaired waterbodies in this watershed include San

Marcos Creek (DDE, phosphorus, sediment toxicity and selenium), Lake San Marcos (ammonia as

nitrogen and nutrients) Batiquitos Lagoon (total coliform) and the Pacific Ocean (total coliform).



Anticipated pollutants to be generated by the project include sediment, nutrients, heavy metals,

organic compounds, trash/debris, oil/grease and bacteria/viruses. Potential pollutants that could

also include oxygen/demanding substances.

The project includes a comprehensive water quality management approach to ensure that there will

not be an increase in pollutant discharge to receiving waters. The comprehensive use of bio

filtration, including bioretention ponds as well as self-treating areas to effectively treat stormwater

runoff prior to discharge from the site and to receiving waters.

Bioretention basins are landscaped depressions or shallow basins used to slow and treat on-site

stormwater runoff. Stormwater is directed to the basin and then percolates through the system

where it is treated by a number of physical, chemical and biological processes. The slowed,

cleaned water is allowed to infiltrate native soils or directed to nearby stormwater drains or

receiving waters. A cross section of a typical bioretention basin is included on Sheet 3 of the WQIP

(Appendix I).

The City’s SUSMP requires that the pollutants of concern for each impaired water body in each

watershed be treated by engineered treatment controls to a medium pollutant removal efficiency or

better prior to leaving each development site. This requirement results in reductions in pollutants.

Bioretention has a high efficiency for removal of sediments, nutrients, trash, metals, oil/grease,

organics and oxygen demanding substances and has a medium efficiency for removal of bacteria.

The bioretention features will be subject to regular inspection and maintenance. The maintenance

requirements are detailed on the last sheet of the WQIP (Appendix I). The property owner is

required, pursuant to the City’s Municipal Code Section 4.15 and the City’s current local SUSMP, to

enter into a stormwater management and discharge control maintenance agreement for the

installation and maintenance of permanent best management practices prior to issuance of permits.

Since the project includes a comprehensive approach to the handling and treatment of stormwater

runoff and will achieve a high efficiency for removal of sediments, nutrients, trash, metals,

oil/grease, organics and oxygen demanding substances and has a medium efficiency for removal of

bacteria, impact to receiving waters would be less than significant.

k) Be tributary to an already impaired water body as listed on the Clean Water Act Section

303(d) list. If so, can it result in an increase in any pollutant for which the water body is

already impaired? Less than Significant Impact












filtration, including bioretention basins as well as self-treating areas to effectively treat stormwater

runoff prior to discharge from the site and to receiving waters.

Bioretention basins are landscaped depressions or shallow basins used to slow and treat on-site

stormwater runoff. Stormwater is directed to the basin and then percolates through the system

where it is treated by a number of physical, chemical and biological processes. The slowed,

cleaned water is allowed to infiltrate native soils or directed to nearby stormwater drains or

receiving waters. A cross section of a typical bioretention basin is included on Sheet 3 of the WQIP

(Appendix I).

The City’s SUSMP requires that the pollutants of concern for each impaired water body in each

watershed be treated by engineered treatment controls to a medium pollutant removal efficiency or

better prior to leaving each development site. This requirement results in reductions in pollutants.

Bioretention has a high efficiency for removal of sediments, nutrients, trash, metals, oil/grease,

organics and oxygen demanding substances and has a medium efficiency for removal of bacteria.

The bioretention features will be subject to regular inspection and maintenance. The maintenance

requirements are detailed on the last sheet of the WQIP (Appendix I). The property owner is

required, pursuant to the City’s Municipal Code Section 4.15 and the City’s current local SUSMP, to

enter into a stormwater management and discharge control maintenance agreement for the

installation and maintenance of permanent best management practices prior to issuance of permits.

Since the project includes a comprehensive approach to the handling and treatment of stormwater

runoff and will achieve a high efficiency for removal of sediments, nutrients, trash, metals,

oil/grease, organics and oxygen demanding substances and has a medium efficiency for removal of

bacteria, impact to impaired water bodies would be less than significant.

l) Be tributary to environmentally sensitive areas (e.g. MSCP, RARE, Areas of Special Biological

Significance, etc.)? If so, can it exacerbate already existing sensitive conditions? Less than

Significant Impact








The project site is located outside of the Biological Resource Conservation area for the MHCP. The

project includes areas that are proposed for wetland restoration, creation and enhancement.



filtration, including bioretention basins as well as self-treating areas to effectively treat stormwater

runoff prior to discharge from the site. Thus the project would not exacerbate already sensitive

conditions and impacts would be less than significant.



m) Have a potentially significant environmental impact on surface water quality, to either

marine, fresh or wetland waters? Less than Significant Impact

The project site supports wetlands and jurisdictional waters. The project will directly impact

wetlands and jurisdictional waters as part of the project development; however, impacts will be

mitigated to below a level of significance through a comprehensive habitat restoration, creation and

preservation effort both on and off-site. The project will implement BMPs during project

construction to minimize potential impact to surface water quality. The project also includes a

comprehensive water quality approach including biofiltration, to reduce pollutants that would be

generated during project operation. Incorporation of these measures would ensure that impacts are

less than significant.

n) Otherwise substantially degrade water quality? Less than Significant Impact

As detailed in IX(j), above, the project includes a comprehensive water quality management

approach. The WQIP is included as Appendix I. The comprehensive use of biofiltration, combined

with on- and off-site riparian enhancement which will further improve water quality. See IX(k),

above. Impacts are less than significant.

o) Place housing within a 100-year flood hazard area as mapped on a federal Flood Hazard

Boundary or Flood Insurance Rate Map or other flood hazard delineation map? No Impact

The project does not propose any housing within a 100-year flood hazard area as mapped on a

federal Flood Hazard Boundary, FIRM, or other flood hazard delineation map. No impact is

identified.

p) Place within a 100-year flood hazard area structures which would impede or redirect flood

flows? No Impact

The project does not propose any structures within a 100-year flood hazard area as mapped on a

federal Flood Hazard Boundary, FIRM, or other flood hazard delineation map. No impact is

identified.

q) Expose people or structures to a significant risk of loss, injury or death involving flooding,

including flooding as a result of the failure of a levee or dam? Less than Significant Impact

The project site is located immediately north and adjacent to South Lake, a storage reservoir with a

dam height of over 75 feet and storage capacity of approximately 300 acre-free at the spillway crest

elevation of 825.5 feet. The Vallecitos Water District is the owner/operator of the lake and its dam.

A Breach Study for South Lake and Development of Inundation Map for Downstream Channel was

prepared by Chang Consultants (2007). The complete study is included as Appendix J of this

document. The purpose of the study was to determine the flood discharge and its downstream

variation as a result of dam failure at South Lake reservoir and to develop an inundation map as a

result of dam failure.



South Lake outlets through a naturally-lined channel aligned through the proposed project site. The

flow continues to Discovery Lake, then along residential areas and a golf course and ultimately

confluences with Dan Marcos Creek near Discovery Street, upstream of Lake San Marcos.

Based upon the inundation mapping prepared for South Lake under a breach condition, all proposed

residences would be located outside of the inundation zone in the event of a breach of the South

Lake Dam. Further, the project will be conditioned to update the inundation study and obtain the

necessary agency approval in order to reflect the project’s current grading concept. Therefore,


r) Inundation by seiche, tsunami, or mudflow? No Impact

The proposed project is not located near a coastline, lake, or mountainous area that would be

subject to a seiche, tsunami, or mudflow. No impacts are identified for this issue area.

X. LAND USE AND PLANNING

a) Physically divide an established community? No Impact

The proposed project would not divide an established community. The project site is currently

undeveloped and would be constructed adjacent to existing residential uses to the north and in the

vicinity of existing multi-family residential uses to the east. The proposed project will provide

infrastructure that would connect offsite residential uses with the proposed park and non-

residential mixed use, also proposed as part of this project. Therefore, no impact is identified for

this issue area.

b) Conflict with any applicable land use plan, policy, or regulation of an agency with jurisdiction

over the project (including, but not limited to the general plan, specific plan, local coastal

program, or zoning ordinance) adopted for the purpose of avoiding or mitigating an

environmental effect? Less than Significant Impact

General Plan

The project site is identified as Focus Area 9 in the General Plan and is identified as a mix of LDR

(Low Density Residential), LMDR (Low Medium Density Residential), MU4 (Mixed Use 4 Non

Residential), OS (Open Space) and P (Park). Per the General Plan, development of 346 single-family

residences, 17 acres of Mixed Use 4 (non-residential mixed use), and 75 acres of park/open space.

The proposed project is consistent with intensity of development contemplated in the General Plan

update. Impacts would be less than significant.

Zoning Ordinance

The project site is zoned Heart of the City Specific Plan. The project includes an amendment to the

Heart of the City Specific Plan. The amended Specific Plan is included as Appendix A.2 of this

document. Implementation of the Specific Plan Amendment, which is one of the discretionary

actions for the project, would make the project consistent with the Zoning Ordinance. Impacts

would be less than significant.



c) Conflict with any applicable habitat conservation plan or natural community conservation

plan? No Impact

The project site is located outside of the Biological Resource Conservation Area for the Multiple

Habitat Conservation Plan. Therefore the project would not conflict with the provisions of an

adopted Habitat Conservation Plan, Natural Community Conservation Plan, or other approved local,

regional, or state habitat conservation plan and no impact is identified.

XI. MINERAL RESOURCES

a) Result in the loss of availability of a known mineral resource that would be a value to the

region and the residents of the state? No Impact

There are no known mineral resources on the site of value to the region or to residents of the state.

Hanson Aggregate operated on the project site in the past, however the operation closed in 2008.

Therefore, the project would not have an impact on any known mineral resource and no impact is


b) Result in the loss of availability of a locally important mineral resource recovery site

delineated on a local general plan, specific plan or other land use plan? No Impact

There are no known mineral resources on the site of value to the region or to residents of the state.

Hanson Aggregate operated on the project site in the past, however the operation closed in 2008.

Therefore, the project would not have an impact on any known mineral resource and no impact is


XII. NOISE

A noise impact analysis was prepared for the project by LdN Consulting (2014). The complete report

is included as Appendix K of this document.

a) Exposure of persons to or generation of noise levels in excess of standards established in the

local general plan or noise ordinance, or applicable standards of other agencies? Less Than


Existing Noise Environment

Noise measurements were taken in four areas of the project site in November 2011. The results of

the noise level measurements are presented in Table 10. The measurements were taken on site to

establish a baseline of the vehicle noise from adjacent Twin Oaks Valley Road and Village Drive. The

measurements were free of obstruction and had a direct line of sight to the roadway. The overall

sound levels were found to be between 44.2 and 70.8 dBA. Construction was occurring to the east

of the project during the measurements. The noise monitoring locations can be seen in Figure 5.



Table 10. Measured Ambient Noise Levels

Measurement

Identification Description Time

Noise Levels (dBA Leq)

Leq Lmax Lmin L10 L50 L90

ML 1 North of the site 12:35-12:53 p.m. 44.2 58.0 33.5 47.8 40.1 36.9



ML 4 Eastern portion of site 1:52-1:58 p.m. 70.8 85.4 54.8 75.1 64.6 57.2

Source: Ldn Consulting (2014)

Future Onsite Noise Analysis – Residential

To control transportation related noise sources such as arterial roads, freeways, airports and

railroads, the City has established guidelines for acceptable community noise levels in the Noise

Element of the General Plan. For noise sensitive rural and single family residential uses, schools,

libraries, parks and recreational areas the City Noise Element requires an exterior noise level of less

than 60 dBA CNEL for outdoor usable areas. For multi-family developments the standard is 65 dBA

CNEL and a standard of 70 dBA CNEL is typically applied to commercial uses.

To determine the future noise environment and impact potentials the Sound32 model was utilized.

Table 11 presents the roadway parameters used in the analysis including the peak traffic volumes,

vehicle speeds and the hourly traffic flow distribution (vehicle mix). The vehicle mix provides the

hourly distribution percentages of automobile, medium trucks and heavy trucks for input into the

Sound32 Model. The Buildout conditions include the future traffic volume forecasts provided in the

Project’s Traffic Study (RBF Consulting, 2014).

Table 11. Future Traffic Parameters

Roadway

Average Daily

Traffic (ADT)1

Peak Hour

Volumes1

Modeled

Speeds

(MPH)

Vehicle Mix %2

Auto

Medium

Trucks

Heavy

Trucks

Twin Oaks Valley Road 40,445

4.056 50 96 2 2

North Village Drive 3,528 353 30 96 2 2

Street A 2,312 231 30 96 2 2


To evaluate the potential noise impacts on the proposed development, outdoor observers were

located throughout the site and placed five feet above the finished pad elevation. The modeled

observer locations for the potential outdoor use areas for both the residential portion of the site

and the mixed-use area are presented in Figure 6. The modeling results are presented in Table 12

for the unmitigated and mitigated scenarios.



Figure 5. Ambient Noise Monitoring Locations



Figure 6. Modeled Receptor Locations



Table 12. Future Exterior Noise Levels

Receptor

Number

Receptor

Location

(Pad #)

Unmitigated

Noise Level (dBA

CNEL)

Barrier Heights

(Feet)

Mitigated Noise

Level (dBA CNEL)

Second Floor

Noise Level (dBA

CNEL)

1 3 56 0 55 56

2 16 55 0 54 55

3 11 57 0 56 58

4 31 56 0 55 58

5 12 57 0 56 57

6 47 55 0 55 55

7 72 60 0 59 60

8 68 60 0 59 59

9 67 56 0 56 56

10 105 59 0 59 59

11 111 59 0 58 59

12 117 60 0 59 59

13 119 57 0 56 59

14 121 57 0 55 59

15 126 57 0 55 60

16 127 56 0 53 58

17 129 56 0 54 58

18 131 57 0 55 58

19 133 56 0 53 53

20 136 60 0 57 58

21 139 57 0 54 57

22 140 63 6 59 62

23 142 64 6 60 63

24 144 66 8 60 64

25 146 66 10 60 64

26 149 66 10 60 63

27 150 63 5 59 63

28 152 63 5 59 62

29 Mixed-Use 67 -- -- 67

30 Mixed-Use 71 -- -- 70

31 Mixed-Use 71 -- -- 71

32 Mixed-Use 65 -- -- 65


Notes:

- = Not applicable

n/a = barrier mitigation not required at this location



Based upon the modeling results, noise mitigation will be required along the top of slope for

some residential pads adjacent to Village Drive, Twin Oaks Valley Drive and future internal streets

(Impact N-1). Therefore, mitigation measures MM-N-1 and MM-N-2 will be required as a condition

of project approval. With implementation of these mitigation measures, onsite noise levels will be

consistent with the Noise Element of the City’s General Plan and will be reduced to below a level of

significance.

MM-N-1 Sound barriers ranging from five to ten feet shall be constructed to reduce future

onsite noise levels to be consistent with the Noise Element of the San Marcos

General Plan (60 dBA CNEL for single family and 65 dBA for multifamily). Locations

and heights of the proposed barriers are presented in Figure 7, Noise Mitigation

Measures. Barriers could include berms, wall, glass or a combination of these to

meet the required noise attenuation.

MM-N-2 A final noise assessment shall be prepared prior to the issuance of the first building

permit. This final report would identify the interior noise requirements based upon

architectural and building plans to meet the City’s established interior noise limit of

45 dBA CNEL2.

Future Onsite Noise Analysis – Non-Residential Mixed Use

No outdoor noise sensitive uses are anticipated on the non-residential mixed-use portion of the

project site; therefore no outdoor impacts from the roadways are anticipated. Table 12 provides

the future unshielded noise levels that would occur at the building façades for the mixed use pads.

As shown in Table 12, mixed-use pads could experience sound level is excess of 70 dBA CNEL in an

unmitigated condition. If outdoor use areas are proposed at the mixed use area (e.g., employee

picnic areas) this would result in a significant impact (Impact N-3). Therefore, mitigation measures

N-3 will be required as a condition of project approval. Implementation of mitigation measures MM-

N-3 would reduce the potential impact to below a level of significance.

MM-N-3 If outdoor usable areas are proposed in the non-residential mixed use areas of the

project, the design shall consider shielding form the buildings, increased setbacks

from the roadways or conduct a site specific noise study to determine compliance.

An interior noise assessment is required to mitigate the exterior noise levels to an

interior level of 50 dBA CNEL. This report should be conducted prior to the issuance

of building permits and would finalize the noise requirements based upon actual


2 Interior noise levels of 45 dBA CNEL can easily be obtained with conventional building construction methods and providing a

closed window condition requiring a means of mechanical ventilation (e.g. air conditioning).



Figure 7. Noise Mitigation Measures – Barrier Height and Locations

b) Exposure of persons to or generation of excessive groundbourne vibrations or groundbourne

noise levels? Less Than Significant Impact

Construction Vibration Analysis

The nearest vibration-sensitive uses are the residences located to the east, 200 feet or more from

the proposed construction. Table 13 lists the average vibration levels that would be experienced at

the nearest vibration sensitive land uses to the east from temporary construction activities. Loaded

trucks will be traveling along the western portion of the site and were assessed at a minimum

distance of 200 feet to be conservative.



Table 13. Vibration Levels from Construction Activities (Residential Receptors)

Equipment

Approximate

Velocity Level

at 25 Feet

(VdB)

Approximate

RMS Velocity

at 25 Feet

(in/sec)

Approximate

Velocity Level

at 200 Feet

(VdB)

Approximate

RMS Velocity

at 200 Feet

(in/sec)

Small bulldozer 58 0.003 33.9 0.0001

Jackhammer

79 0.035 54.9 0.0015

Loaded trucks 86 0.076 61.9 0.0034

Large bulldozer 87 0.089 62.9 0.0039

FTA Criteria 80 0.2

Significant Impact? No No

Note: 1 PPV at Distance D = PPVref x (25/D)

1.5

The Federal Transit Administration (FTA) has determined vibration levels that would cause

annoyance to a substantial number of people and potential damage to building structures. The FTA

criterion for vibration induced structural damage is 0.20 in/sec for the peak particle velocity (PPV).

Project construction activities would result in PPV levels below the FTA’s criteria for vibration

induced structural damage. Therefore, construction activities would not result in vibration-induced

structural damage to residential buildings near the demolition and construction areas. The FTA

criterion for infrequent vibration induced annoyance is 80 Vibration Velocity (VdB) for residential

uses. Construction activities would generate levels of vibration that would not exceed the FTA

criteria for nuisance for nearby residential uses. Therefore, vibration impacts would be less than

significant.

Blasting Vibration Analysis

The City of San Marcos Title 17 of the City’s Municipal Code states that all blasting operations within

the City of San Marcos are prohibited unless a Certificate of Authorization is first obtained from the

San Marcos Building Director and an Operations Permit issued by the Fire Chief. Additional relevant

sections of the City’s Code for Blasting are provided below:

• The general contractor or property owner/developer shall give reasonable notice in writing

at the time of issuance of a building permit, grading permit or encroachment license to all

residences or businesses within 600 feet of any potential blast location. The notice shall be

in a form approved by the Building Director. Any resident or business receiving such notice

may request of the Building Director that a notice of impending blasting be given by the

blaster at the time of the 12 hour advance notice given to the Building Director. The general

contractor or property owner/developer shall make all reasonable efforts to contact any

and all parties requesting the second notice.

• The blaster shall file a written certification with the Building Director certifying that the

general notice required by Section 17.60.060(b) has been given. The certificate shall include

addresses and date(s) of notification. A copy shall be retained on file at the Building Division.

• Inspections of all structures within 300 feet of the blast site shall be made before blasting

operations. The persons inspecting shall obtain the permission of the building owner to



conduct an inspection. The inspections shall be done by a registered structural engineer

employed by the blaster or project contractor. The inspection shall be only for the purpose

of determining the existence of any visible or reasonably recognizable pre-existing defects

or damages in any structure. Inspection refusal shall be at the discretion of the property

owner.

• Blasting shall only be permitted between the hours of 9:00 a.m. and 4:00 p.m. during any

weekday, Monday through Friday, exclusive of City recognized holidays unless special

circumstances warrant another time or day and special approval is granted by the Building

Director and Fire Chief.

Blasting for construction projects typically results in an RMS vibration velocity of about 100 VdB at

50 feet from the blast based on FTA findings. This is equivalent to a peak particle velocity of about

0.4 inch per second. As discussed above the smallest distance between an existing residence and

the blasting activity was assumed to be 200 feet. Given attenuation of vibration velocities with

distance, the RMS vibration velocity and peak particle velocity at the nearest existing residence

would be about 82 VdB and 0.05 inch per second, respectively. Based on the construction vibration

damage criteria published by the FTA, the threshold vibration levels for damage to "Non-engineered

timber and masonry buildings" are 94 VdB and 0.20 inch per second. Therefore, the effect of the

blasting activity on nearby residential structures will not be significant. However, it should be noted

that the human annoyance criterion of 80 VdB would be slightly exceeded when blasting occurred

within about 250 feet of existing residences. If blasting is required within 250 feet of existing

residences, the potential annoyance may not be completely avoided but can be minimized by

following the City’s blasting procedures as stated above, and with proper notice annoyances can be

avoided.

c) A substantial permanent increase in ambient noise levels in the project vicinity above levels

existing without the project? Less Than Significant With Mitigation Incorporated

Project Related Offsite Transportation Noise

Because mobile/traffic noise levels are calculated on a logarithmic scale, a doubling of the traffic

noise or acoustical energy results in a noise level increase of 3 dBA. Therefore the doubling of the

traffic volume, without changing the vehicle speeds or mix ratio, results in a noise increase of 3 dBA.

Community noise level changes greater than 3 dBA are often identified as audible and considered

potential significant, while changes less than 1 dBA will not be discernible to local residents. In the

range of 1 to 3 dBA, residents who are very sensitive to noise may perceive a slight change.

Community noise exposures are typically over a long time period rather than the immediate

comparison made in a laboratory situation. Therefore, the level at which changes in community

noise levels become discernible is likely greater than 1 dBA and 3 dBA appears to be appropriate for

most people. For the purposes for this analysis a direct and cumulative roadway noise impacts

would be considered significant if the project increases noise levels for a noise sensitive land use by

3 dBA CNEL and if the project increases noise levels above an unacceptable noise level per the City’s

General Plan in the area adjacent to the roadway segment.

The projected off-site Project related roadway segment noise levels were calculated using the

methods in the Highway Noise Model published by the Federal Highway Administration (FHWA



Highway Traffic Noise Prediction Model, FHWA-RD-77-108, December, 1978).

Project Direct Off-Site Noise Impact Analysis

To determine if direct off-site noise level increases associated with the development of the

proposed project will create noise impacts. The noise levels for the existing conditions were

compared with the noise level increase from the Project. Utilizing traffic assessment prepared for

the project (RBF Consulting 2014) noise contours were developed for the following traffic scenarios:

• Existing: Current day noise conditions without construction of the project.

• Existing Plus Project: Current day noise conditions plus the completion of the project.

• Existing vs. Existing Plus Project: Comparison of the direct project related noise level

increases in the vicinity of the project site.

The noise levels and reference distances to the 60 dBA CNEL contours for the roadways in the

vicinity of the Project site are given in Table 14 for the Existing Scenario and in Table 15 for the

Existing Plus Project Scenario. It should be noted that the values in Tables 14 and 15 do not take

into account the effect of any noise barriers or topography that may affect ambient noise levels.

Table 14. Existing Roadway Noise Levels

Roadway Roadway Segment ADT1

Vehicle

Speeds

(MPH)1

Noise Level

@ 50-Feet

(dBA CNEL)

60 dBA CNEL

Contour

Distance

(Feet)

Twin Oaks Valley Rd.

SR-78 Ramps to Barham Dr. 39,465 50 76.2 2,108

Barham Dr. to Campus Marketplace 28,659 50 74.9 1,531

Campus Marketplace to Craven Rd. 29,990 50 75.1 1,602

Craven Rd. to North Village Dr. 21,750 50 73.7 1,162

North Village Dr. to South Village Dr. 17,491 50 72.7 934

South Village Dr. to School-Park Access 17,056 50 72.6 911

South of School-Park Access 17,056 50 72.6 911

Craven Road

Twin Oaks Valley Rd. to Rush Dr. 10,294 45 69.4 432

Rush Dr. to Echo Lane 15,746 45 71.2 661

Echo Lane to Santa Barbara Drive 16,013 45 71.3 672

Santa Barbara Dr. Craven Rd. to Orchid Avenue 1,181 30 57.0 25

Village Drive North Twin Oaks Valley Road to Carnation Ct. 1,038 30 56.4 22




Table 15. Existing + Project Roadway Noise Levels


Vehicle

Speeds

(MPH)1

Noise Level

@ 50-Feet

(dBA CNEL)

60 dBA CNEL

Contour

Distance

(Feet)






North Village Dr. to South Village Dr. 21,009 50 73.5 1,122

South Village Dr. to Site Access 19,329 50 73.1 1,032

South of Site Access 18,976 50 73.1 1,013

Craven Road







Table 16 presents the comparison of the Existing Year with and without Project related noise levels. As

shown in Table 16, the overall roadway segment noise levels will increase from 0.0 dBA CNEL to 4.9 dBA

CNEL with the development of the proposed project.

Table 16. Existing vs. Existing + Project Roadway Noise Levels

Roadway Roadway Segment

Existing

Noise Level

@ 50-Feet

(dBA CNEL)

Existing Plus

Project

Noise Level

@ 50-Feet

(dBA CNEL)

Project

Related

Noise Level

Increase

(dBA CNEL)


SR-78 Ramps to Barham Dr. 76.2 76.6 0.4

Barham Dr. to Campus Marketplace 74.9 75.4 0.5

Campus Marketplace to Craven Rd. 75.1 75.6 0.5

Craven Rd. to North Village Dr. 73.7 74.5 0.8

North Village Dr. to South Village Dr. 72.7 73.5 0.8

South Village Dr. to Site Access 72.6 73.1 0.5

South of Site Access 72.6 73.1 0.5

Craven Road

Twin Oaks Valley Rd. to Rush Dr. 69.4 69.7 0.3

Rush Dr. to Echo Lane 71.2 71.5 0.3

Echo Lane to Santa Barbara Drive 71.3 71.7 0.4

Santa Barbara Dr. Craven Rd. to Orchid Avenue 57.0 59.8 2.8

Village Drive North Twin Oaks Valley Road to Carnation Ct. 56.4 61.3 4.9




The only segment that has an increase of 3dBA CNEL or greater is the segment of Village Drive North

between Twin Oaks Valley Road and Carnation Court. The overall noise level is 61.3 dBA CNEL with no

shielding along this segment. However, the side and rear yards of existing residences along this segment

of roadway have a minimum five-foot wall already in place. Barriers of this height typically provide a

reduction of 3 to 5 decibels, and those residences that are below the grade of Village Drive North will

have further noise reductions due to grade separation. Thus, the existing walls will reduce the noise

level below the 60 dBA CNEL threshold. Therefore, the Project’s direct contribution to off-site roadways

is less than significant.

Cumulative Off-Site Noise Impact Analysis

To determine if cumulative off-site noise level increases associated with the development of the Project

and other planned or permitted projects in the vicinity will create noise impacts. The noise levels for the

near-term Project Buildout and other planned and permitted projects were compared with the existing

conditions. Utilizing the Project’s traffic assessment (RBF Consulting, 2012) noise contours were

developed for the following traffic scenarios:

• Existing: Current day noise conditions without construction of the project.

• Existing Plus Cumulative Projects Plus Project: Current day noise conditions plus the completion

of the project and the completion of other permitted, planned projects or approved ambient

growth factors.

• Existing vs. Existing Plus Cumulative Plus Project: Comparison of the existing noise levels and

the related noise level increases from the combination of the project and all other planned or

permitted projects in the vicinity of the site.

The existing noise levels and reference distances to the 60 dBA CNEL contours for the roadways in the

vicinity of the project site are given in Table 14 above for the Existing Scenario. The near-term

cumulative noise conditions are provided in Table 17. No noise barriers or topography that may affect

noise levels were incorporated in the calculations.

Table 17. Existing + Project + 2030 Cumulative Roadway Noise Levels


Vehicle

Speeds

(MPH)1

Noise Level

@ 50-Feet

(dBA CNEL)

60 dBA CNEL

Contour

Distance (Feet)






North Village Dr. to South Village Dr. 30,869 50 75.2 1,649

South Village Dr. to Site Access 29,002 50 74.9 1,549

South of Site Access 28,560 50 74.8 1,525

Craven Road









Table 18 presents the comparison of the Existing Year and the Near-Term Cumulative noise levels. The

overall roadway segment noise levels will increase from 0.3 dBA CNEL to 5.3 dBA CNEL with the

development of the Project.

The only segment that has an increase of 3dBA CNEL or greater is the segment of Village Drive North

between Twin Oaks Valley Road and Carnation Court. The overall noise level is 61.7 dBA CNEL with no

shielding. However, the side and rear yards of existing residences along this segment of roadway have a

minimum five-foot wall already in place. Barriers of this height typically provide a reduction of 3 to 5

decibels, and those residences that are below the grade of Village Drive North will have further noise

reductions due to grade separation. Thus, the existing walls will reduce the noise level below the 60

dBA CNEL threshold. Therefore, the Project’s direct contribution to off-site roadways is less than

significant. Therefore, the Project’s direct contributions to off-site roadways is less than significant.

Table 18. Existing vs. Existing + Project + 2030 Cumulative Roadway Noise Levels

Roadway Roadway Segment

Existing Noise

Level @ 50 Feet

(dBA CNEL)

Existing Plus

Project Noise

Level @ 50 Feet

(dBA CNEL)

Project

Related

Noise Level

Increase

(dBA CNEL)


SR-78 Ramps to Barham Dr. 76.2 77.7 1.5

Barham Dr. to Campus Marketplace 74.9 76.3 1.4

Campus Marketplace to Craven Rd. 75.1 76.4 1.3

Craven Rd. to North Village Dr. 73.7 75.9 2.2

North Village Dr. to South Village Dr. 72.7 75.2 2.5

South Village Dr. to Site Access 72.6 74.9 2.3

South of Site Access 72.6 74.8 2.2

Craven Road

Twin Oaks Valley Rd. to Rush Dr. 69.4 71.1 1.7

Rush Dr. to Echo Lane 71.2 71.6 0.4

Echo Lane to Santa Barbara Drive 71.3 71.6 0.3

Santa Barbara Dr. Craven Rd. to Orchid Avenue 57.0 59.8 2.8

Village Drive North Twin Oaks Valley Road to Carnation Ct. 56.4 61.7 5.3


In summary, the proposed project does create a direct and cumulative noise increase of more than 3

dBA CNEL on a segment of Village Drive North, however, this increase does not take into

consideration existing barriers and walls, which provide shielding/noise attenuation. The overall

noise level is 61.7 dBA CNEL with no shielding. However, the side and rear yards of existing

residences along this segment of roadway have five-foot barriers already in place. Barriers of this

height typically provide a reduction of 3 to 5 decibels, thus they will reduce the noise level below the

60 dBA CNEL threshold. Therefore, the Project’s direct and cumulative contributions to off-site

roadway noise increases are less than significant to any existing or future noise sensitive land uses.

d) A substantial temporary or periodic increase in ambient noise levels in the project vicinity

above levels existing without the project? Less Than Significant Impact

Construction noise represents a short-term impact on the ambient noise levels. Noise generated by

construction equipment includes haul trucks, water trucks, graders, dozers, loaders and scrapers can



reach relatively high levels. Grading activities typically represent one of the highest potential

sources for noise impacts. The most effective method of controlling construction noise is through

local control of construction hours and by limiting the hours of construction to normal weekday

working hours.

The City of San Marcos Municipal Code addresses the limits grading, extraction and construction

activities between 7:00 a.m. and 4:30 p.m. Monday through Friday and no grading, extraction or

construction is allowed on the weekends or holidays. The Municipal code does not set noise limits

on construction activities. Commonly, the City has utilized the County of San Diego’s Noise

Ordinance noise limit of 75 dBA for other projects.

The U.S. Environmental Protection Agency (U.S. EPA) has compiled data regarding the noise

generating characteristics of specific types of construction equipment. Noise levels generated by

heavy construction equipment can range from 60 dBA to in excess of 100 dBA when measured at 50

feet. However, these noise levels diminish rapidly with distance from the construction site at a rate

of approximately 6 dBA per doubling of distance. For example, a noise level of 75 dBA measured at

50 feet from the noise source to the receptor would be reduced to 69 dBA at 100 feet from the

source to the receptor, and reduced to 63 dBA at 200 feet from the source.

Using a point-source noise prediction model, calculations of the expected construction noise

impacts were completed. The essential model input data for these performance equations include

the source levels of each type of equipment, relative source to receiver horizontal and vertical

separations, the amount of time the equipment is operating in a given day, also referred to as the

duty-cycle and any transmission loss from topography or barriers.

The equipment needed for the development will consist of up to a tractor/backhoe, a hydraulic

crane, a loader/grader, a side boom, a water truck, a concrete truck, a concrete pump, haul trucks, a

paver, a roller/compactor, a scraper and a drill rig. Based on the EPA noise emissions, empirical data

and the amount of equipment needed, worst case noise levels from the construction equipment for

site preparation would occur during the grading operations. Additionally, the project will utilize a

Terex Pegson XA750 rock crusher. This equipment is utilized separately from the grading equipment

and will be analyzed separately.

Construction Grading Noise Analysis

The grading activities will consist of the preparation of internal roadways, parking and the finished

pads. The grading equipment will be spread out over the Project site from distances near the

occupied property lines to distances of 350 feet or more away. Based upon the site plan the

majority of the grading operations, on average, will occur more than 350 feet from the property

lines. This means that most of the time the average distance from all the equipment to the nearest

property line is over 350 feet. Table 19 presents the anticipated construction noise levels. As can be

seen in Table 19, at an average distance of 350 feet from the construction activities to the nearest

property line would result in a noise attenuation of -16.9 dBA.



Table 19. Construction Noise Levels

Equipment Type Quantity Used Source @ 50 Feet (dBA)

Cumulative Noise Level @

50 Feet (dBA)

Tractor/Backhoe 1 72 72.0

Dozer D9 Cat 1 74 74.0

Hydraulic Crane 1 78 78.0

Loader/Grader 1 73 73.0

Side Boom 1 72 72.0

Water Trucks 1 70 70.0

Concrete Trucks 1 75 75.0

Concrete Pump 1 82 82.0

Dump Trucks 1 75 75.0

Paver/Blade 1 75 75.0

Roller/Compactor 1 74 74.0

Scraper 1 75 75.0

Drill Rig 1 83 83.0

Haul Trucks 4 75 81.0

Cumulative Level 89.0

Distance to Sensitive Use 350

Noise Reduction due to Distance -16.9

Property Line Noise Level 72.1

Given this, the noise levels will comply with the 75 dBA Leq standard at the property lines. To help

control the noise levels from the haul trucks a speed limit of 15 MPH should be posted along the on-

site haul route and signage limiting the use of engine “jake” brakes. Additionally, all equipment

should be properly fitted with mufflers and all staging and maintenance should be conducted as far

away for the existing residence as possible. These requirements have been identified as design

features for the project. Therefore, impacts are less than significant and no mitigation is required

during construction of the proposed project.

Rock Crusher Analysis

Due to bedrock conditions, rock crushing may be required during project construction. Rock

crushing would occur between the hours of 7:00 AM and 4:00 PM. The rock crushing equipment will

be located in the northwestern corner of the Mixed-Use site near the access road, more than

1,000 feet from the nearest residence. Based on empirical data collected at a material processing

plant in the City of Upland noise levels from a rock crusher ranged between 80-86 dBA at 45 feet

(Ldn 2011). A worst-case noise level of 86 dBA at 45 feet will be utilized for the analysis.

As can be seen in Table 20, in order to achieve the City’s 60 dBA Leq standard, the rock crusher

needs to be 1,000 feet from the nearest residence. The nearest residence to the proposed rock

crusher location is over 1,000 feet. Figure 8 shows the noise contour of the rock crushing

operations. Given this, the noise levels will comply with the City’s 60 dBA Leq standard at the

property lines. However, should there be a change in rock crusher location or rock crusher type,

there is the potential for a significant noise impact (Impact N-4). Thus implementation of mitigation

measure MM-N-4 will be required as a condition of project approval. Implementation of MM-N-4

will reduce the potential impact to below a level of significance.



Table 20. Rock Crushing Noise Levels

Equipment Type

Quantity

Used

Source @ 50 Feet

(dBA)

Cumulative Noise Level

@ 50 Feet (dBA)

Terex Pegson XA750 Rock Crusher 1 86 86.0

Distance to Sensitive Use 1,000

Noise Reduction due to Distance -26.0

Property Line Noise Level 60.0

Figure 8. Rock Crusher Noise Contour



MM-N-4 If rock crushing is proposed, upon starting of crushing operations, noise

measurements of the rock crushing facility shall be required to ensure compliance

with the City’s thresholds. If noise levels are found to be above the established

thresholds of 60 dBA at any existing single family residential use, 65 dBA for any

multifamily use or 70 dBA at a commercial use then additional mitigation in the

form of berms or temporary walls will need to be incorporated into the rock crusher

design to reduce the noise levels to below the City’s thresholds.

e) For a project located within an airport land use plan or, where such a plan has not been

adopted, within two miles of a public airport or public use airport, would the project expose

people residing or working in the project area to excessive noise levels? No Impact

The nearest airport is the Palomar Airport in Carlsbad, which is located approximately six miles west

of the project area. At this distance, the airport would not subject future residents or workers in the

project area to excessive noise levels due to airport operations. Therefore, no impact is identified.

f) For a project within the vicinity of a private airstrip, would the project expose people residing

or working in the project area to excessive noise levels? No Impact

The project site is not located within the vicinity of a private airstrip. Therefore, no impact is


XIII. POPULATION AND HOUSING

a) Induce substantial population growth in an area, either directly (for example, by proposing

new homes and businesses) or indirectly (for example, through extension of roads or other

infrastructure)? Less than Significant Impact

The project proposes the construction of 346 residential units, 24.1 acres of non-residential mixed

use, an approximately 38 acre active park, and associated infrastructure. This will result in an

approximately 1,100 new residents. The proposed development is consistent within the existing

General Plan and proposed adjacent to an area that is already developed with residential. Utility

infrastructure will be sized to serve the project. Proposed roadways will connect to existing

roadways and are provided to serve the project and not any future development areas. Therefore,

impacts would be less than significant for this issue area.

b) Displace substantial numbers of existing housing, necessitating the construction of

replacement housing elsewhere? No Impact

There is no existing housing on the project site. The project site coincides with the former Hanson

Aggregate site, as well as undeveloped natural open space. Therefore, the construction would not

result in the displacement of any people, nor would it necessitate the construction of replacement

housing elsewhere. Therefore, no impact is identified for this issue area.



c) Displace substantial numbers of people, necessitating the construction of replacement

housing elsewhere? No Impact

There is no existing housing or residents on the project site. The project site coincides with the

former Hanson Aggregate site, as well as undeveloped natural open space. Therefore, the

construction would not result in the displacement of any people, nor would it necessitate the

construction of replacement housing elsewhere. Therefore, no impact is identified for this issue

area.

XIV. PUBLIC SERVICES

a) Fire protection? Less Than Significant Impact

The project site would increase demand on fire protection services due to the construction of 346

residential units, 24 acres of non-residential mixed use development and 38 acres of active park. The

City of San Marcos Fire Department was contacted for their input on the project, including

information regarding stations serving the project, current staffing, response times and other items

related to fire protection services. The Fire Department’s response is included in Appendix L.

The project site is closest to Station 1 and Station 4. Fire Station 1 is located at 180 West Mission

and is staffed with one paramedic engine company (3 personnel), one paramedic truck company (3

personnel) and one paramedic ambulance (2 personnel). Fire Station 4 is located at 204 San Elijo

Road and is staffed with one paramedic engine company (3 personnel), paramedic ambulance (2

personnel) and one battalion chief. Average response times to the project site from either Station 1

or 4 are approximately four minutes based upon most current response data.

The San Marcos Fire Department (2013) indicated that current staff levels and equipment at these

stations are adequate to serve the project; however, the Fire Department continues to experience

an increase in emergency and non-emergency response and additional resources will be needed in

the future. The project would be contained within a preexisting Fire Community Facilities District

and impacts are less than significant.

Additionally, the project will implement the following design features, per fire department

requirements:

• Roadways serving the project shall have a minimum improved paved width of 24 feet with

an additional 8 feet to each side for parking. Any deviations from this or any other roadway

features such as cul-de-sacs and gates must meet the design criteria of the San Marcos Fire

Department.

• Any automatic gates are required to have a Knox rapid entry system and emergency vehicle

strobe detector.

• Fire hydrants with an adequate water supply must be installed at locations approved by the

San Marcos Fire Department. Hydrant spacing shall be 300 feet apart.

• Residential structures shall be fire sprinklered per California Building Code 2010 edition and

city ordinance.



• Homes and mixed use buildings will be required to be designed using state fire marshal

standards for fire resistive construction features using the California Building Code 2013

edition Chapter 7, design to be reviewed by City Building Department.


As discussed in Section VIII(h), the project proposes development adjacent to natural areas which

will be preserved as open space. This creates and areas where development will be adjacent to

wildland areas that have a high fire risk. This represents a significant impact (Impact HAZ-2).

Implementation of mitigation measures MM-HAZ-2, which requires preparation and

implementation of a Fire Protection Plan will reduce this impact to below a level of significance.

b) Police protection? Less Than Significant Impact

The project site would increase demand on police protection services due to the construction of 346

residential units, 24 acres of non-residential mixed use development and 38 acres of active park. The

San Diego County Sheriff’s Department was contacted for their input on the project, including

information regarding stations serving the project, current staffing, response times and other items

related to police protection services. The Sheriff Department’s response is included in Appendix L.

The project site would be served by the San Marcos Station located at 182 Santar Place, which is

located approximately four miles from the project site. Based upon information from Corporal

Malcolm Horst (2013), current staffing levels are adequate to meet current demand. The addition of

development associated with this project will result in an increase in demand on police protection

services. Additionally, the Sheriff’s Department encouraged the use of design features in the project

that are consistent with the “Crime Prevention Through Environmental Design” techniques.

Any incremental effects of the project on police protection services will be offset by the City

requirement for payment of fees to a preexisting Community Facilities District for police protection.

Therefore, impacts to police protection services are determined to be less than significant.

c) Schools? Less than Significant Impact

The project is located within the service boundary of the San Marcos Unified School District

(SMUSD). Existing schools that would serve the project include:

• Discovery Elementary School, 730 Applewilde Drive

• San Elijo Elementary School, 1615 School House Way

• San Elijo Middle School, 600 School House Way

• San Marcos High School, 1615 San Marcos Boulevard

The current enrollment and planned capacity of each of these schools is presented below. Due to

overcrowding in the district, interim relocatable classrooms are used at various sites in the district.

Additionally, some students are house at schools outside their attendance area and may be bussed

to those sites.



School Enrollment Permanent Capacity

Discovery Elementary School 987 638

San Elijo Elementary School 1,225 838

San Elijo Middle School 1,499 1,484

San Marcos High School 2,242 2,961

Based upon correspondence from SMUSD (2012) (Appendix L), development of 346 residential units

is expected to generate approximately 86 elementary school students, 37 middle school students

and 44 high school students. Based upon the available capacity at the schools that would serve the

project, student generation associated with the project would exceed current capacity at the

elementary and middle schools. These additional students would need to be accommodated

through the addition of classrooms on these campuses, or within the increase capacity generated by

future K-8 school planned within the District. The project applicant will be required to pay school

mitigation fees pursuant to California Education Code Section 17620 and Government Code Section

65995. These fees will assist in funding the SMUSD’s long-rage plans. Current Level II school fees are

$4.58/s.f. for residential and $0.51/s.f. for commercial.

d) Parks? Less than Significant Impact

The City has 22 developed parks as well an extensive trail network. The closest existing park to the

project site is Double Peak Park (900 Double Peak Drive), which is approximately 2.5 miles south of

the project site. Double Peak Park includes picnic area, trails, a playground, amphitheater, scenic

views and restroom facilities. The future South Lake Park will be located immediately south of the

project site. South Lake Park will include a dog park, picnic area, scenic viewing, trails, and restroom

facilities. South Lake Park is scheduled to open is included in the City’s Capital Improvement

Program but an opening date is yet to be determined.

The project proposes 38.43 acres of active park area that would be developed in the future with a

variety of active park uses, including ball fields. The proposed park facility will add to the overall

park and recreation amenities in the City. Therefore impacts are less than significant.

e) Other public facilities? Less than Significant Impact

In Sections XIV(a) through XIV(d), the analysis concluded that the project would have a less than

significant impact related to police protection, fire protect, schools and parks. The project would not

result in an impact to any other public facilities. Impacts are less than significant.

XV. RECREATION

a) Would the project increase the use of existing neighborhood and regional parks or other

recreational facilities, such that substantial physical deterioration of the facility would occur

or be accelerated? Less than Significant Impact

The City has 22 developed parks as well an extensive trail network. The closest existing park to the

project site is Double Peak Park (900 Double Peak Drive), which is approximately 2.5 miles south of

the project site. Double Peak Park includes picnic area, trails, a playground, amphitheater, scenic



views and restroom facilities. The future South Lake Park will be located immediately south of the

project site. South Lake Park will include a dog park, picnic area, scenic viewing, trails, and restroom

facilities.

The project proposes over 38 acres of active park area that would be developed in the future with a

variety of active park uses, including ball fields. The proposed park facility will add to the overall

park and recreation amenities in the City.

Since the project provides adequate recreational amenities, the project would not result in

substantial physical deterioration of any facilities and impacts are less than significant.

b) Does the project include recreational facilities or require the construction or expansion of

recreational facilities, which might have an adverse physical effect on the environment? Less

Than Significant Impact

The project includes approximately 38-acres of active park are which would be developed at a

future time. Additionally small pocket parks are incorporated into the residential area. Any

impacts associated with these uses are analyzed within this environmental document. Impacts

are less than significant.

XVI. TRANSPORTATION/TRAFFIC

A traffic impact analysis was prepared for the project by RBF Consulting (2014). The complete report

is included as Appendix M of this document. The project study area included 11 intersections and 12

roadway segments and considered the following analysis scenarios:

• Existing Conditions

• Existing Plus Project Conditions

• Year 2016 Cumulative Conditions Without Project

• Year 2016 Cumulative Conditions With Project (Phase One)

• Year 2020 Cumulative Conditions Without Project

• Year 2020 Cumulative Conditions With Project (Phase Two)

• Horizon Year 2030 Conditions Without Project

• Horizon Year 2030 Conditions With Project (Phase Two)

a) Cause an increase in traffic, which is substantial in relation to the existing traffic load and

capacity of the street system (i.e., result in a substantial increase in either the number of

vehicle trips, the volume to capacity ratio on roads, or congestion at intersections)? Less Than


Existing Level of Service

To determine the existing operation of the study intersections, intersection turning movement

counts were taken on a typical weekday during the a.m. (7:00 to 9:00 a.m.) and p.m. (4:00 to 6:00

p.m.) peak period. Table 21 summarizes the existing a.m. and p.m. peak hour intersection LOS of

the study intersections based on the existing peak hour intersection volumes and existing

intersection geometry. As shown in Table 21, all study intersections currently operate at acceptable

levels of service (LOS D) or better during the peak hours.



Table 21. Existing Peak Hour Intersection Conditions

Study Intersection

Existing Conditions

AM Delay (1)

–

LOS

PM Delay (1)

–

LOS

Twin Oaks Valley Rd / SR-78 WB Ramps 14.7 – B 17.1 – B

Twin Oaks Valley Rd / SR-78 EB Ramps 33.4 - C 31.6 – C

Twin Oaks Valley Rd / Discovery St – Barham Dr 27.2 – C 31.6 – C

Twin Oaks Valley Rd / Campus Marketplace 13.7 – B 20.8 – C

Twin Oaks Valley Rd / Craven Rd 25.3 – C 34.7 – C

Twin Oaks Valley Rd / North Village Dr 23.8 – C 25.1 – C

Twin Oaks Valley Rd / South Village Dr 6.0 – A 6.1 – A

Craven Rd / Rush Dr 29.9 – C 36.0 – D

Craven Rd / Echo Lane 12.6 – B 10.8 – B

Craven Rd / Santa Barbara Dr (2)

11.3 – B 14.2 – B

Note: Deficient intersection operation indicated in bold. (1)

Seconds of delay per vehicle. (2)

Unsignalized, two-way stop-sign controlled intersection.

Daily roadway segment levels of service were calculated based on the roadway classification and

capacity as well as existing ADT volumes. Table 22 presents the results of the existing conditions

daily roadway segment level of service analysis. As shown in Table 22, all study roadway segments

currently operate at acceptable levels of service (LOS D or better).

Table 22. Existing Daily Roadway Segment Conditions

Roadway Location

Class

(# Lanes)

LOS E

Capacity

Existing

ADT V/C LOS

Twin Oaks

Valley Rd.

SR-78 Ramps to Barham Dr./ Discovery St. Prime (8) 70,000 39,465 0.564 B

Barham Dr./Discovery St. to Campus Marketplace Prime (6) 60,000 28,659 0.478 B

Campus Marketplace to Craven Rd. Prime (6) 60,000 29,990 0.500 B

Craven Rd. to North Village Dr. Prime (6) 60,000 21,750 0.363 A

North Village Dr. to South Village Dr. Prime (6) 60,000 17,491 0.292 A

South of South Village Dr. Major (5) 45,000 17,056 0.379 A

Craven Rd.

Twin Oaks Valley Rd. to Rush Dr. Major (4) 40,000 10,294 0.257 A

Rush Dr. to Echo Lane Major (4) 40,000 15,746 0.394 B

Echo Lane to Santa Barbara Dr. Major (4) 40,000 16,013 0.400 B

Santa

Barbara Dr. Craven Rd. to Orchid Ave. Collector (2) 8,000 1,181 0.148 A

North

Village Dr. Carnation Court to Twin Oaks Valley Rd. Collector (2) 8,000 1,038 0.130 A

Note: Deficient roadway segment operation shown in bold.



Project Trip Generation

To determine the trips forecast to be generated by the proposed project, April 2002 SANDAG Trip

Generation rates were utilized in accordance with the City of San Marcos and SANTEC/ITE Traffic

Study Guidelines. As shown in Table 23, Phase One of the proposed project will generate

approximately 1,260 trips per day, which includes approximately 101 a.m. peak hour trips and

approximately 126 p.m. peak hour trips. Phase Two (project build-out including Phase One) will

generate approximately 8,926 trips per day, which includes approximately 857 a.m. peak hour trips

and approximately 942 p.m. peak hour trips.

Table 23. Proposed Project Trip Generation

Land Use Units

Daily

(per unit)

AM Peak PM Peak

Total In Out Total In Out

Single Family Residential DU 10 8% 30% 70% 10% 70% 30%

Active Park AC 30 13% 50% 50% 9% 50% 50%

Business Park TSF 16 12% 80% 20% 12% 20% 80%

Specialty Retail TSF 40 3% 60% 40% 9% 50% 50%

Land Use Size Unit

Daily

Trips

AM Peak PM Peak

Total In Out Total In Out

Forecast Project Generated Trips

Phase One (2016)

Single Family Residential 126 DU 1,260 101 30 71 126 88 38

Total Phase I Trips 1,260 101 30 71 126 88 38

Phase Two - Includes Phase One Development (2020)

Single Family Residential 346 DU 3,460 277 83 194 346 242 104

Active Park 35 AC 1,050 137 68 68 95 47 47

Business Park (MU-4 site) 216 TSF 3,456 415 332 83 415 83 332

Specialty Retail (MU-4 site) 24 TSF 960 29 17 12 86 43 43

Total Project Trips 8,926 857 500 356 942 416 526

Source: SANDAG (Not So) Brief Guide of Vehicular Traffic Generation Rates for the San Diego Region (April 2002).

Existing + Project Condition Analysis

Existing plus project conditions evaluates the impact of the build-out of the proposed project

(completion of Phase One and Phase Two) on the existing roadway network. The Phase Two project

trip distribution assumes that a total of 10% of the project trips will remain internal to the site, with

approximately 5 percent of the trips being captured between the residential and park uses, and

approximately 5 percent of the trips being captured between the residential and business

park/retail use.

The addition of project-generated trips is not forecast to result in a change in operating conditions

from acceptable to deficient at any of the study intersections. As shown in Table 24, consistent with

existing conditions, the study intersections are forecast to continue operating at LOS D or better

with the addition of traffic generated by the proposed project.



Table 24. Existing Plus Project Peak Hour Intersection Conditions

Study Intersection

Existing Conditions Existing + Project

Change

in Delay(1)

AM Delay(1)

LOS

PM Delay(1)

LOS

AM Delay(1)

LOS

PM Delay(1)

LOS AM PM

Twin Oaks Valley Rd / SR-78 WB Ramps 20.2 – C 17.1 – B 20.8 – C 17.9 – B 0.6 0.8

Twin Oaks Valley Rd / SR-78 EB Ramps 33.4 – C 29.0 - C 37.7 - D 31.5 - C 4.3 2.5

Twin Oaks Valley Rd / Discovery St – Barham Dr 31.2 – C 31.6 – C 31.2 – C 31.6 – C 0.0 0.0

Twin Oaks Valley Rd / Campus Marketplace 14.3 – B 20.8 – C 14.3 – B 20.8 – C 0.0 0.0

Twin Oaks Valley Rd / Craven Rd 29.2 – C 34.7 – C 29.2 – C 35.9 – D 0.0 1.2

Twin Oaks Valley Rd / North Village Dr 27.1 – C 25.1 – C 30.6 – C 26.0 – C 3.5 0.9

Twin Oaks Valley Rd / South Village Dr 6.4 – A 6.1 – A 15.7 – B 20.3 – C 9.3 14.2

Craven Rd / Rush Dr 34.7 – C 36.0 – D 34.7 – C 36.7 – D 0.0 0.7

Craven Rd / Echo Ln 12.8 – B 10.8 – B 14.2 – B 11.0 – B 1.4 0.2


11.3 – B 14.2 – B 12.3 – B 16.3 – C 1.0 2.1

Twin Oaks Valley Rd / South Project Access – – 5.6 – A 11.2 – B – –

Note: Deficient intersection operation shown in bold. (1)



The results of the Existing Plus Project conditions daily roadway segment analysis is presented in

Table 25. Table 25 shows that consistent with existing conditions, all study roadway segments are

forecast to operate at LOS D or better with the addition of project-generated trips to existing daily

roadway segment volumes and impacts are less than significant.

Year 2016 Cumulative Conditions – With and Without Project Analysis

To determine the Year 2016 Cumulative conditions in the project study area, forecast project traffic

associated with City of San Marcos approved or pending projects was added to existing traffic

volumes. Cumulative project traffic data through the study area is based on information from traffic

impact studies. Cumulative projects are forecast to generate approximately 52,861 trips per day,

which includes approximately 4,553 a.m. peak hour trips and approximately 5,194 p.m. peak hour

trips.

Year 2016 Cumulative Conditions Level of Service Analysis

Table 26 summarizes the Year 2016 Cumulative conditions peak hour intersection analysis using

HCM methodology, without and with the proposed project. As shown in Table 26, all intersections

are forecast to operate at LOS D or better in the 2016 cumulative peak hour condition.



Table 25. Existing Plus Project Daily Roadway Segment Conditions

Segment Location

Class

(# Lanes)

LOS E

Capacity

Existing Existing + Project Change

in V/C ADT V/C LOS ADT V/C LOS

Twin Oaks

Valley Rd.

SR-78 Ramps to Barham Dr./

Discovery St. Prime (8) 70,000 39,465 0.564 B 43,136 0.616 C 0.052

Barham Dr./Discovery St. to

Campus Marketplace Prime (6) 60,000 28,659 0.478 B 32,635 0.544 B 0.066

Campus Marketplace to Craven Rd. Prime (6) 60,000 29,990 0.500 B 34,195 0.570 B 0.070

Craven Rd. to North Village Dr. Prime (6) 60,000 21,750 0.363 A 26,531 0.442 B 0.080

North Village Dr. to South Village Dr. Prime (6) 60,000 17,491 0.292 A 21,009 0.350 A 0.059

South Village Dr. to South Project-

Park Access Major (5) 45,000 17,056 0.379 A 19,329 0.430 B 0.051

South of South Project Access Major (5) 45,000 17,056 0.379 A 18,976 0.422 B 0.043

Craven Rd.

Twin Oaks Valley Rd. to Rush Dr. Major (4) 40,000 10,294 0.257 A 11,090 0.277 A 0.020

Rush Dr. to Echo Lane Major (4) 40,000 15,746 0.394 B 16,725 0.418 B 0.024

Echo Lane to Santa Barbara Dr. Major (4) 40,000 16,013 0.400 B 17,445 0.436 B 0.036

Santa Barbara Dr. Craven Rd. to Orchid Avenue Collector (2) 8,000 1,181 0.148 A 2,409 0.301 A 0.153

North Village Dr. Twin Oaks Valley Road to

Carnation Court Collector (2) 8,000 1,038 0.130 A 3,188 0.399 B 0.269




Table 26. Year 2016 Cumulative Peak Hour Intersection Conditions - Without and With Project

Study Intersection

Without Project With Project

Change in

Delay(1)

AM Delay(1)

LOS

PM Delay(1)

LOS

AM Delay(1

LOS

PM Delay(1)

LOS AM PM

Twin Oaks Valley Rd / SR-78 WB Ramps 21.0 – C 18.6 – B 21.0 – C 18.8 – B 0.0 0.2

Twin Oaks Valley Rd / SR-78 EB Ramps 40.1 - D 34.3 - C 40.8 - D 35.0 - D 0.7 0.7

Twin Oaks Valley Rd / Discovery St-Barham Dr 33.4 – C 39.9 – D 33.5 – C 40.1 – D 0.1 0.2

Twin Oaks Valley Rd / Campus Marketplace 16.9 – B 23.8 - C 16.9 – B 24.0 – C 0.0 0.2

Twin Oaks Valley Rd / Craven Rd 33.1 – C 39.8 – D 33.2 – C 40.5 – D 0.1 0.7


Twin Oaks Valley Rd / South Village Dr 7.2 – A 6.1 – A 7.2 – A 6.1 – A 0.0 0.0

Craven Rd / Rush Dr 36.5 – D 42.2 – D 36.7 – D 43.5 – D 0.2 1.3



12.5 – B 16.6 – C 13.1– B 17.5 – C 0.6 0.9

Twin Oaks Valley Rd / South Project Access – – – – – –

Note: Deficient intersection operation shown in bold. Change in delay shown in bold indicates a significant impact. (1)




capacity as well as ADT volumes. Table 27 presents the results of the Year 2016 Cumulative

conditions roadway segment level of service analysis, without and with the proposed project. As

shown in Table 27, all study roadway segments are forecast to operate at acceptable levels of

service (LOS D or better) both without and with the proposed project under Year 2016 Cumulative

Conditions.




volumes. Cumulative project traffic data through the study area is based on information from traffic

impact studies. Cumulative projects are forecast to generate approximately 52,861 trips per day,


trips.



HCM methodology, without and with the proposed project. As shown in Table 26, all intersections

are forecast to operate at LOS D or better in the 2016 cumulative peak hour condition.



Table 27. Year 2016 Cumulative Daily Roadway Segment Conditions - Without and With Project

Segment Location

Class

(# Lanes)

LOS E

Capacity

Year 2016 Without

Project Year 2016 With Project Change


Twin Oaks

Valley Rd.

SR-78 Ramps to Barham Dr./ Discovery St. Prime (8) 70,000 48,534 0.693 C 49,076 0.701 C 0.008


Campus Marketplace Prime (6) 60,000 33,364 0.556 B 33,855 0.564 B 0.008

Campus Marketplace to Craven Rd. Prime (6) 60,000 34,489 0.575 B 35,056 0.584 C 0.009

Craven Rd. to North Village Dr. Prime (6) 60,000 29,678 0.495 B 30,081 0.501 B 0.007

North Village Dr. to South Village Dr. Prime (6) 60,000 25,017 0.417 B 25,307 0.422 B 0.005

South Village Dr. to South Project Access Major (5) 45,000 24,681 0.548 B 24,971 0.555 B 0.006

South of South Project Access Major (5) 45,000 24,681 0.548 B 24,971 0.555 B 0.006

Craven Rd.

Twin Oaks Valley Rd. to Rush Dr. Major (4) 40,000 14,702 0.368 A 14,891 0.372 A 0.005

Rush Dr. to Echo Lane Major (4) 40,000 20,928 0.523 B 21,243 0.531 C 0.008

Echo Lane to Santa Barbara Dr. Major (4) 40,000 21,595 0.540 C 22,036 0.551 C 0.011



Carnation Court Collector (2) 8,000 1,086 0.136 A 1,779 0.222 A 0.087







volumes. The cumulative projects are forecast to generate approximately 97,290 trips per day,


trips. To determine the Year 2020 Cumulative operating conditions at the study intersections, the

cumulative project trips were added to the existing volumes at the intersections and roadway

segments within the project study area.

The Year 2020 Cumulative Conditions analysis assumes the completion of the following roadway

improvements within the project study area:

• Extension of Discovery Street from Bent Avenue to Twin Oaks Valley Road, constructed as

six-lane Prime Arterial.

• Intersection improvements at Twin Oaks Valley Road / Discovery Street-Barham Drive:

o Two left-turn lanes, three through lanes and one right-turn lane at westbound

approach

o Removal of existing free-right turn lanes at southbound, eastbound and westbound

approaches, replaced with standard right-turn lanes.

o Right-turn overlap phases provided at southbound and westbound intersection

approaches

• Southbound approach of Twin Oaks Valley Road / Campus Marketplace Access restriped to

provide a second left-turn lane into CSUSM campus parking lot area.

The Discovery Street extension will divert existing traffic away from Craven Road and Rush Drive,

and level of service at the intersection of Craven Road / Rush Drive will improve to an acceptable

LOS C during the peak hours under Year 2020 Cumulative Conditions.



HCM methodology, without and with the proposed project.

As shown in Table 28, all intersections are forecast to operate at an acceptable level of under Year

2020 Cumulative Conditions both without and with the proposed project:



Table 28. Year 2020 Cumulative Peak Hour Intersection Conditions Without and With Project

Study Intersection


Change in

Delay(1)

AM Delay(1)

LOS

PM Delay(1)

LOS

AM Delay(1)

LOS

PM Delay(1)

LOS AM PM

Twin Oaks Valley Rd / SR-78 WB Ramps 21.7 – C 20.1 – C 22.4 – C 22.8 – C 0.7 2.7

Twin Oaks Valley Rd / SR-78 EB Ramps 43.5 - D 40.9 - D 49.3 - D 48.3 - D 5.8 7.4

Twin Oaks Valley Rd / Discovery St – Barham Dr 29.5 – C 42.2 – D 29.7 – C 49.5 – D 0.2 7.3


Twin Oaks Valley Rd / Craven Rd 33.4 – C 39.4 – D 36.0 – D 46.6 – D 2.6 7.2


Twin Oaks Valley Rd / South Village Dr 7.2 – A 6.0 – A 13.8 – B 18.8 – B 6.6 12.8

Craven Rd / Rush Dr 30.2 – C 29.3 – C 30.2 – C 29.7 – C 0.0 0.4



11.1 – B 13.0 – B 12.0 – B 14.5 – B 0.9 1.5

Twin Oaks Valley Rd / South Project Access – – 5.6 – A 8.9 – A – –





capacity as well as ADT volumes. Table 29 presents the results of the Year 2020 Cumulative

conditions roadway segment level of service analysis, without and with the proposed project. As

shown in Table 28, all study roadway segments are forecast to operate at acceptable levels of

service (LOS D or better) both without and with the proposed project under Year 2020 Cumulative

Conditions.

Horizon Year 2030 Conditions Level of Service Analysis

The results of the Horizon Year 2030 intersection level of service analysis are summarized in

Table 30.



Table 29. Year 2020 Cumulative Daily Roadway Segment Conditions - Without and With Project

Segment Location

Class

(# Lanes)

LOS E

Capacity

Year 2020 Without

Project Year 2020 With Project

Change


Twin Oaks

Valley Rd.

SR-78 Ramps to Barham Dr./ Discovery St. Prime (8) 70,000 51,181 0.731 C 54,561 0.779 C 0.048


Campus Marketplace Prime (6) 60,000 35,219 0.587 C 39,484 0.658 C 0.071

Campus Marketplace to Craven Rd. Prime (6) 60,000 36,256 0.604 C 40,715 0.679 C 0.074

Craven Rd. to North Village Dr. Prime (6) 60,000 31,553 0.526 B 36,746 0.612 C 0.087

North Village Dr. to South Village Dr. Prime (6) 60,000 27,174 0.453 B 30,869 0.514 B 0.062

South Village Dr. to South Project Access Major (5) 45,000 26,838 0.596 C 29,002 0.644 C 0.048

South of South Project Access Major (5) 45,000 26,838 0.596 C 28,560 0.635 C 0.038

Craven Rd.

Twin Oaks Valley Rd. to Rush Dr. Major (4) 40,000 14,140 0.354 A 15,185 0.380 B 0.026





Carnation Court Collector (2) 8,000 1,086 0.136 A 3,472 0.434 B 0.298




Table 30. Horizon Year 2030 Peak Hour Intersection Conditions - Without and With Project

Study Intersection


Change in

Delay(1)

AM Delay(1)

LOS

PM Delay(1)

LOS

AM Delay(1)

LOS

PM Delay(1)

LOS AM PM

Twin Oaks Valley Rd / SR-78 WB Ramps 23.8 – C 24.3 – C 25.0 – C 30.2 – C 1.2 5.9

Twin Oaks Valley Rd / SR-78 EB Ramps 82.4 – F 65.5 – F 94.1 – F 76.0 – F 11.7 10.5

Twin Oaks Valley Rd / Discovery St – Barham Dr 34.4 – C 55.1 – E 35.5 – D 66.0 – E 1.1 10.9


Twin Oaks Valley Rd / Craven Rd 30.8 – C 39.6 – D 32.2 – C 45.9 – D 1.4 6.3


Twin Oaks Valley Rd / South Village Dr 7.1 – A 5.9 – A 13.8 – B 18.7 – B 6.7 12.8

Craven Rd / Rush Dr 31.8 – C 32.0 – C 32.1 – C 32.8 – C 0.3 0.8



11.5 – B 14.2 – B 12.7 – B 16.0 – C 1.2 1.8

Twin Oaks Valley Rd / South Project Access – – 5.5 – A 8.0 – A – –




As shown in Table 30, the following intersections are forecast to operate at deficient levels of

service (LOS E or F) under Horizon Year 2030 Conditions both without and with the proposed

project:

• Twin Oaks Valley Road / SR-78 Eastbound Ramps (a.m./p.m.: LOS F)

• Twin Oaks Valley Road / Discovery Street–Barham Drive (p.m.: LOS E)

The addition of project-related traffic to the above-listed intersections results in an increase in delay

that exceeds the significance threshold of 2.0 seconds. Therefore, the project will result in a

significant impact at Twin Oaks Valley Road / SR-78 Eastbound Ramps (Impact TR-1) and Twin Oaks

Valley Road / Discovery Street–Barham Drive (Impact TR-2) under Horizon Year 2030 Conditions,

and mitigation measures are required.

MM-TR-1 The project applicant shall make a fair share contribution towards the following

improvements at the Twin Oaks Valley Road/SR-78 Eastbound Ramps:

• Construct an additional dedicated right-turn lane at eastbound (off-ramp)

approach of intersection.

• Restripe eastbound approach to include one left-turn lane, one shared left-

turn/through/right-turn lane, and two right-turn lanes.

MM-TR-2 The project applicant shall make a fair share contribution towards the widening of

the northbound approach of the Twin Oaks Valley Road/Discover Street-Barham

Drive intersection to construct a dedicated right-turn lane.



The project applicant shall pay fair share payments towards the improvements identified in

MM-TR-1 and MM-TR-2. Implementation of mitigation measure MM-TR-1 will improve the LOS from

F to E in the AM Peak hour, improve LOS in the PM peak hour, and reduce impacts to below a level

of significance.

Implementation of mitigation measure MM-TR-2 will improve the LOS from D to C in the AM peak

hour and E to D in the PM peak hour and reduce impacts to below a level of significance.


capacity as well as ADT volumes. Table 31 presents the results of the Horizon Year 2030 Conditions

roadway segment level of service analysis, without and with the proposed project As shown in

Table 31, all study roadway segments are forecast to operate at acceptable levels of service (LOS D

or better) both without and with the proposed project under Horizon Year 2030 Conditions.

Site Access and Internal Circulation

The project will take access from Santa Barbara Drive, North Village Drive, South Village Drive and a

new signalized intersection and access road at the south end of the project site. The residential

units built in Phase One will take access from Santa Barbara Drive and North Village Drive. Phase

One includes construction of the “Backbone Road” that will extend from the existing terminus of

Santa Barbara Drive to the proposed western extension of North Village Drive.

Phase Two will construct the remaining portion of the “Backbone Road from North Village Drive to

the intersection of Twin Oaks Valley Road / South Village Drive. The southerly access intersection,

traffic signal and road will also be constructed during Phase Two to provide access to the proposed

business park and retail uses located at the southern end of the site.

Roundabouts are proposed for the future intersection of North Village Drive / “Backbone Road” and

at another intersection of the “Backbone Road” with a local access street internal to the project site.

A third roundabout is also being considered for the existing intersection of North Village Drive and

Carnation Court, which is located approximately 350 feet west of the signalized intersection of Twin

Oaks Valley Road and North Village Drive. Currently this is a three-legged intersection that is

controlled by stop signs at all approaches. However, there is currently no through traffic on North

Village Drive as the road terminates a few hundred feet west of Carnation Court. One of the

proposed neighborhoods within the project site will take access from North Village Drive across

from Carnation Court, which will add a fourth leg to the intersection of North Village Drive /

Carnation Court. Although the forecast through traffic on North Village Drive at Carnation Court is

relatively low, the existing all-way stop sign control is not optimal due to the close proximity of the

intersection to the signalized intersection at Twin Oaks Valley Road. A roundabout at the North

Village Drive / Carnation Court would improve the flow of traffic through the intersection and

eliminate any potential for queues spilling back from the existing stop signs.



Table 31. Horizon Year 2030 Daily Roadway Segment Conditions - Without and With Project

Segment Location

Class

(# Lanes)

LOS E

Capacity

Year 2030 Without Project Year 2030 With Project Change


Twin Oaks

Valley Rd.

SR-78 Ramps to Barham Dr./ Discovery St. Prime (8) 70,000 59,048 0.844 D 62,428 0.892 D 0.048


Campus Marketplace Prime (6) 60,000 38,564 0.643 C 42,829 0.714 C 0.071

Campus Marketplace to Craven Rd. Prime (6) 60,000 39,665 0.661 C 44,124 0.735 C 0.074

Craven Rd. to North Village Dr. Prime (6) 60,000 42,876 0.715 C 48,069 0.801 C 0.087

North Village Dr. to South Village Dr. Prime (6) 60,000 36,750 0.613 C 40,445 0.674 C 0.062

South Village Dr. to South Project Access Major (5) 45,000 34,937 0.776 C 37,101 0.824 D 0.048

South of South Project Access Major (5) 45,000 34,437 0.765 C 36,159 0.804 D 0.038

Craven Rd.

Twin Oaks Valley Rd. to Rush Dr. Major (4) 40,000 18,365 0.459 B 19,410 0.485 B 0.026




North Village Dr. Twin Oaks Valley Road to Carnation Court Collector (2) 8,000 1,142 0.143 A 3,528 0.441 C 0.298




b) Exceed, either individually or cumulatively, a level of service standard established by the

county congestion management agency for designated roads or highways? Less Than


The traffic report (RBF Consulting, 2013) included an analysis of Caltrans facilities and this section

summarizes the results.

Caltrans Facilities Analysis – ILV Analysis

The results of the Caltrans ILV analysis are summarized in Table 32. As shown in Table 32, operations

at Twin Oaks Valley Road / SR-78 Eastbound Ramps exceed the Capacity threshold of 1,500

intersecting lane volumes per hour during both the a.m. and p.m. peak hours for Year 2016

Cumulative Conditions through Horizon Year 2030 Conditions both without and with the proposed

project. Operations at the intersection of Twin Oaks Valley Road / SR-78 Westbound Ramps exceed

the Capacity threshold of 1,500 intersecting lane volumes per hour during the p.m. peak hour for

Year 2020 Cumulative Conditions through Horizon Year 2030 Conditions both without and with the

proposed project.

Peak Hour Freeway Segment Analysis

The following segments of SR-78 were evaluated under all study scenarios without and with the

proposed project:

• SR-78 from San Marcos Boulevard interchange to Twin Oaks Valley Road interchange

• SR-78 from Twin Oaks Valley Road interchange to Barham Drive-Woodland Parkway

interchange

A 5 percent heavy truck factor was applied based on information reported by Caltrans for these

segments of SR-78. A measured free-flow speed of 65 mph was used in the HCM calculations for

freeway segments. Auxiliary lanes are included in the freeway segment analysis, which are currently

provided in both directions of travel between the interchange ramps on SR-78 from San Marcos

Boulevard to Twin Oaks Valley Road.

Existing (Year 2010) peak hour freeway segment volumes were provided by Caltrans. To determine

the Existing Plus Project operating conditions on the freeway segments, the project-generated trips

were added to the existing peak hour freeway segment volumes. The results of the Existing and

Existing Plus Project conditions peak hour freeway segment analysis are presented in Table 33.

As shown in Table 33, the study freeway segments currently operate at acceptable levels of service

(LOS D or better) except for Westbound SR-78 from Woodland Parkway to Twin Oaks Valley Road,

which is currently operating at LOS F during the a.m. peak hour and at LOS E during the p.m. peak

hour. Under existing plus project conditions, the study freeway segments will continue operating at

acceptable levels of service except for Westbound SR-78 from Woodland Parkway to Twin Oaks

Valley Road.


Draft Initial Study/MITIGATED Negative Declaration March 2014

Table 32. Caltrans ILV Analysis Summary

Intersection


AM Peak Hour PM Peak Hour AM Peak Hour PM Peak Hour

Flow Operations Flow Operations Flow Operations Flow Operations

Existing Conditions

Twin Oaks Valley Rd./ SR-78 WB Ramps 708 Stable 845 Stable 804 Stable 976 Stable

Twin Oaks Valley Rd./ SR-78 EB Ramps 1,346 Unstable 1,160 Stable 1,494 Unstable 1,323 Unstable

Year 2016 Cumulative Conditions

Twin Oaks Valley Rd./ SR-78 WB Ramps 861 Stable 1,082 Stable 875 Stable 1,097 Stable

Twin Oaks Valley Rd./ SR-78 EB Ramps 1,613 Capacity 1,465 Unstable 1,632 Capacity 1,486 Unstable

Year 2020 Cumulative Conditions

Twin Oaks Valley Rd./ SR-78 WB Ramps 922 Stable 1,210 Unstable 1,003 Stable 1,322 Unstable

Twin Oaks Valley Rd./ SR-78 EB Ramps 1,708 Capacity 1,635 Capacity 1,834 Capacity 1,776 Capacity

Horizon Year 2030 Conditions

Twin Oaks Valley Rd./ SR-78 WB Ramps 1,126 Stable 1,347 Unstable 1,208 Unstable 1,459 Unstable

Twin Oaks Valley Rd./ SR-78 EB Ramps 2,155 Capacity 1,850 Capacity 2,281 Capacity 1,991 Capacity

Note: ILV operations at capacity indicated in bold.


Draft Initial Study/MITIGATED Negative Declaration March 2014

Table 33. Peak Hour Freeway Segment Analysis Existing / Existing Plus Project Conditions

Freeway From To

Existing Conditions Existing Plus Project Conditions Change

in Speed

(mph) Volume LOS

Speed

(mph) D Volume LOS

Speed

(mph) D

AM Peak Hour

SR-78 EB San Marcos ON TOVR OFF 5,073 C 65.0 21.0 5,159 C 65.0 21.4 0.0

SR-78 WB TOVR ON San Marcos OFF 6,278 D 64.6 26.2 6,329 D 64.5 26.5 -0.1

SR-78 EB TOVR ON Barham OFF 5,129 D 63.5 29.1 5,191 D 63.3 29.5 -0.2

SR-78 WB Woodland ON TOVR OFF 6,616 F * * 6,707 F * * *

PM Peak Hour


SR-78 WB TOVR ON San Marcos OFF 5,671 C 65.0 23.5 5,764 C 65.0 23.9 0.0


SR-78 WB Woodland ON TOVR OFF 6,048 E 57.7 37.7 6,125 E 57.0 38.7 -0.7

Note: Deficient freeway segment operation indicated in bold where applicable.

D =Density, Passenger Cars per Mile per Lane



Year 2016 and year 2030 peak hour freeway segment volumes are based on traffic volumes and

forecasts developed by Caltrans District 11 Office of Advanced Planning and are consistent with

traffic forecast volumes used on the recent auxiliary lane studies on SR-78 between San Marcos

Boulevard and Woodland Parkway, and between Woodland Parkway and Nordahl Road. The

forecast growth on each freeway segment was calculated from 2016 to 2030, and annual growth

rates were applied to each freeway segment to develop the forecast freeway volumes in the year

2020. Forecast a.m. and p.m. trips generated by the proposed project were added to the Year 2016,

year 2020 and year 2030 base freeway segment volumes.

The SANDAG 2050 Regional Transportation Plan (RTP) includes the construction of one Managed

Lane in each direction of travel on SR-78 from I-5 to I-15 in the Revenue Constrained Plan. The SR-

78 Managed Lanes Project is programmed to be completed by the year 2020. Therefore, this

planned improvement is included in the Year 2020 Cumulative Conditions and Horizon Year 2030

Conditions analysis.

The City of San Marcos in conjunction with Caltrans proposes to construct new auxiliary lanes in

both directions on SR-78 between the San Marcos Boulevard interchange and Woodland

Parkway/Barham Drive interchange, and extending through the Twin Oaks Valley Road interchange.

The proposed auxiliary lanes project on SR-78 is not currently funded, but the project is supported

by SANDAG and funding to construct this project is currently being pursued.

The proposed new auxiliary lanes on SR-78 are assumed to be constructed after Year 2016 but prior

to year 2020. It is assumed that when the SR-78 Managed Lanes Project is completed by 2020, the

new auxiliary lanes would be converted to through traffic lanes to construct the Managed Lane

adjacent to the center median in both directions of travel.

Table 34 summarizes the results of the Year 2016 Cumulative conditions freeway segment analysis

without and with the proposed project, which assumes the existing freeway capacity. As shown in

Table 34, the study freeway segments are forecast to operate at acceptable levels of service (LOS D

or better) under Year 2016 Cumulative conditions except for the following:

• Eastbound SR-78 from Twin Oaks Valley Road to Woodland Parkway-Barham Drive (AM/PM:

LOS E)

• Westbound SR-78 from Woodland Parkway-Barham Drive to Twin Oaks Valley Road

(AM/PM: LOS F)

The Year 2020 Cumulative conditions freeway segment analysis without and with the proposed

project is presented in Table 35, which assumes the construction of the programmed Managed

Lanes Project on SR-78. It is assumed that the proposed new auxiliary lanes would be converted to

through traffic lanes to construct the Managed Lane adjacent to the center median in both

directions of travel. As shown in Table 35, the study freeway segments are forecast to operate at

acceptable levels of service (LOS D or better) under Year 2020 Cumulative conditions both without

and with the proposed project.



Table 34. Peak Hour Freeway Segment Analysis Year 2016 Cumulative Conditions

Freeway From To

Without Project With Project Change in Speed

(mph) Volume LOS Speed (mph) D Volume LOS

Speed (mph) D

AM Peak Hour


SR-78 WB TOVR ON San Marcos OFF 6,774 D 63.7 28.7 6,785 D 63.6 28.8 -0.1

SR-78 EB TOVR ON Barham OFF 5,945 E 58.6 36.5 5,959 E 58.5 36.6 -0.1

SR-78 WB Woodland ON TOVR OFF 7,083 F * * 7,089 F * * *

PM Peak Hour

SR-78 EB San Marcos ON TOVR OFF 6,365 D 64.5 26.6 6,378 D 64.4 26.7 -0.1

SR-78 WB TOVR ON San Marcos OFF 6,108 C 64.8 25.5 6,114 C 64.7 25.5 -0.1

SR-78 EB TOVR ON Barham OFF 6,611 F * * 6,619 F * * *






Table 35. Peak Hour Freeway Segment Analysis Year 2020 Cumulative Conditions

Freeway From To

Without Project With Project Change

in Speed

(mph) Volume LOS

Speed

(mph) D Volume LOS

Speed

(mph) D

AM Peak Hour



SR-78 EB TOVR ON Barham OFF 6,381 D 64.4 26.7 6,436 D 64.4 27.0 0.0

SR-78 WB Woodland ON TOVR OFF 7,459 D 61.2 32.9 7,540 D 60.8 33.4 -0.4

PM Peak Hour




SR-78 WB Woodland ON TOVR OFF 6,973 D 63.1 29.8 7,042 D 62.9 30.2 -0.2





Table 36 summarizes the results of the Horizon Year 2030 conditions freeway segment analysis

without and with the proposed project, which assumes the construction of the programmed

Managed Lanes Project on SR-78. As shown in Table 36, the study freeway segments are forecast to

operate at acceptable levels of service (LOS D or better) under Horizon Year 2030 conditions except

for the following:

• Eastbound SR-78 from Twin Oaks Valley Road to Woodland Parkway-Barham Drive (PM: LOS

E)

• Westbound SR-78 from Woodland Parkway-Barham Drive to Twin Oaks Valley Road

(AM/PM: LOS E)

Peak Hour Freeway Ramp Metering Analysis

Freeway ramp meters are currently operating at the northbound to westbound SR-78 on-ramp at

Twin Oaks Valley Road, the southbound to westbound SR-78 on-ramp at Twin Oaks Valley Road, and

the eastbound SR-78 on-ramp at Twin Oaks Valley Road. The southbound to westbound SR-78 on-

ramp at Twin Oaks Valley Road is not included in this analysis because trips associated with the

proposed project would not be added to this on-ramp.

The northbound to westbound SR-78 on-ramp at Twin Oaks Valley Road has ramp meters operating

during the a.m. peak period from 5:30 a.m. to 9:30 a.m. Ramp meters are currently operating

during the p.m. peak period from 3:30 p.m. to 7:00 p.m. at the eastbound SR-78 on-ramp at Twin

Oaks Valley Road.

The existing lane configurations and meter flow rates for each study area freeway on-ramp are as

follows:

Twin Oaks Valley Road Westbound On-Ramp from NB Approach (a.m. peak metering)

• One single-occupancy vehicle (SOV) lane / One high-occupancy vehicle (HOV) lane

• Meter flow rate: 570 vehicles per hour per lane (2 cars per green)

Twin Oaks Valley Road Eastbound On-Ramp (p.m. peak metering)

• Two single-occupancy vehicle (SOV) lanes / One high-occupancy vehicle (HOV) lane

• Meter flow rate: 570 vehicles per hour per lane (2 cars per green)

It is assumed that the current hourly ramp meter flow rate will be maintained in the future study

scenarios. This assumption is conservative because there are planned improvements on SR-78

through the study area that will increase freeway capacity and improve peak hour flow and level of

service. The existing ramp meter rates are based on the existing capacity and operations, and with

capacity improvements to the freeway, it is likely that the future ramp meter rates would be

adjusted.

Table 37 summarizes the results of the ramp metering analysis under all analysis scenarios. As

shown in Table 37, the peak hour demand at the study ramp meters currently does not exceed the

hourly meter flow rate capacities shown in the table. Table 37 shows that the addition of project-

related traffic to existing ramp volumes will not result in peak hour demand exceeding the hourly

meter flow rate capacities; therefore, no delay or queue lengths were calculated at the ramp meters

under Existing Plus Project conditions.



Table 36. Peak Hour Freeway Segment Analysis Horizon Year 2030 Conditions

Freeway From To

Without Project With Project Change

in Speed

(mph) Volume LOS

Speed

(mph) D Volume LOS

Speed

(mph) D

AM Peak Hour

SR-78 EB San Marcos ON TOVR OFF 7,192 C 65.0 23.9 7,263 C 64.9 24.1 -0.1

SR-78 WB TOVR ON San Marcos OFF 7,883 D 64.5 26.4 7,924 D 64.5 26.5 0.0



PM Peak Hour


SR-78 WB TOVR ON San Marcos OFF 7,637 C 64.8 25.5 7,715 C 64.7 25.7 -0.1

SR-78 EB TOVR ON Barham OFF 7,770 E 59.6 35.2 7,859 E 59.1 35.9 -0.5






Table 37. Peak Hour Freeway Ramp Metering Analysis

Ramp

Peak

Hour

Demand

(Ramp

Volume)

Meter

Flow Rate(1)

Number

of Lanes(2)

Excess

Demand

Delay

(Minutes)

Queue

Length

(in feet)

Existing Conditions

TOVR WB On-Ramp AM 378 570 1.1 0 0 0

TOVR EB On-Ramp PM 939 570 2.2 0 0 0

Existing Plus Project Conditions

TOVR WB On-Ramp AM 429 570 1.1 0 0 0

TOVR EB On-Ramp PM 1,038 570 2.2 0 0 0

Year 2016 Cumulative Conditions Without Project

TOVR WB On-Ramp AM 459 570 1.1 0 0 0

TOVR EB On-Ramp PM 1,145 570 2.2 0 0 0

Year 2016 Cumulative Conditions With Project

TOVR WB On-Ramp AM 470 570 1.1 0 0 0

TOVR EB On-Ramp PM 1,153 570 2.2 0 0 0


TOVR WB On-Ramp AM 487 570 1.1 0 0 0

TOVR EB On-Ramp PM 1,242 570 2.2 0 0 0

Year 2020 Cumulative Conditions With Project

TOVR WB On-Ramp AM 528 570 1.1 0 0 0

TOVR EB On-Ramp PM 1,331 570 2.2 29 3 724

Horizon Year 2030 Conditions Without Project

TOVR WB On-Ramp AM 597 570 1.1 0 0 0

TOVR EB On-Ramp PM 1,537 570 2.2 122 13 3,041

Horizon Year 2030 Conditions With Project

TOVR WB On-Ramp AM 638 570 1.1 4 0 105

TOVR EB On-Ramp PM 1,626 570 2.2 162 17 4,043

Notes: (1)

Vehicles per hour per lane. (2)

Previous studies have shown that HOV lanes are utilized by approximately 10% of the total freeway traffic during the peak

hours. The capacity of the SOV and HOV lanes on the ramps were calculated based on the proportion of traffic using each

lane.

It is assumed that the current hourly ramp meter flow rate will be maintained in the future study

scenarios.

The results of the Year 2016 Cumulative Conditions analysis show that the peak hour demand is not

forecast to exceed the current hourly meter flow rate capacities either without or with the proposed

project. Therefore, no delay or queue lengths were calculated at the ramp meters under Year 2016

Cumulative conditions.

As shown in Table 37, the p.m. peak hour demand at the Twin Oaks Valley Road Eastbound On-

Ramp is forecast to exceed the current hourly meter flow rate capacities under Year 2020

Cumulative Conditions with the proposed project. The forecast ramp meter delay is less than 15

minutes and therefore is not considered deficient an excessive delay.

The results of the Horizon Year 2030 Conditions ramp meter analysis show that the p.m. peak hour



demand at the Twin Oaks Valley Road Eastbound On-Ramp is forecast to exceed the current hourly

meter flow rate capacities either without or with the proposed project. The forecast ramp meter

delay with the proposed project is more than 15 minutes and therefore is considered deficient an

excessive delay according to SANTEC/ITE TIS Guidelines.

Queuing Analysis

A queuing analysis was conducted during the a.m. and p.m. peak hours at the intersection of Twin

Oaks Valley Road / SR-78 Eastbound Ramps under all analysis scenarios without and with the

proposed project. At the request of Caltrans, an Existing Plus Phase One Project scenario was also

included in this queuing analysis, which was not evaluated in the intersection level of service

analysis.

The purpose of the queuing analysis is to determine if the proposed project results in queuing

impacts to the freeway lanes on eastbound SR-78 where the Twin Oaks Valley Road off-ramp

diverges from the freeway mainline lanes. The SYNCHRO software program was utilized to conduct

the queuing analysis, which reports both 50th percentile (average) and 95th percentile (maximum)

queue lengths.

There are currently two lanes exiting the SR-78 freeway at the Twin Oaks Valley Road eastbound off-

ramp, which transition to three lanes approaching the intersection with Twin Oaks Valley Road. The

total length of the off-ramp from the freeway mainline lanes to Twin Oaks Valley Road is

approximately 780 feet. An auxiliary lane approximately 2,150 feet in length is currently provided

along eastbound SR-78 between the on-ramp at San Marcos Boulevard and the off-ramp at Twin

Oaks Valley Road.

There are currently three eastbound approach lanes at the intersection with Twin Oaks Valley Road:

one left-turn lane, one shared left-turn/through/right-turn lane, and one right-turn lane. The left-

turn lane is constructed as a turn bay and is approximately 300 feet in length. The two off-ramp

lanes transition to the center and right-turn intersection approach lanes, and have a total length of

approximately 780 feet.

All analysis scenarios assume the existing lane configuration at the eastbound intersection

approach, with the exception of the mitigated condition under Horizon Year 2030 conditions with

the project, which includes a total of four lanes at the eastbound approach of the intersection. The

recommended additional right-turn lane at the intersection is assumed to have a length of 300 feet

to be consistent with the existing lanes at the intersection approach.

The results of the queuing analysis at Twin Oaks Valley Road / SR-78 Eastbound Ramps under

existing plus project conditions are summarized in Table 38. The Year 2016 and Year 2020

cumulative conditions analysis results are summarized in Table 39. Table 40 presents the results of

the Horizon Year 2030 conditions analysis, without and with the recommended mitigation measure.

As shown in Tables 38 and 39, the reported and adjusted 95th percentile queue lengths are not

forecast to exceed the total length of the eastbound off-ramp lanes (780 feet) under existing, Year

2016 and Year 2020 cumulative conditions with the proposed project.



Table 38. Peak Hour Intersection Queuing Analysis Twin Oaks Valley Road / SR-78 Eastbound Ramps (Existing /

Existing Plus Project Conditions)

Ramp and Intersection Approach Lane

#

Lanes

Length

(feet)

AM Peak Hour PM Peak Hour

Volume

Per

Lane (1)

Reported

50%

Queue (2)

Reported

95%

Queue (2)

Adjusted

95%

Queue (3)

Volume

Per

Lane (1)

Reported

50%

Queue (2)

Reported

95%

Queue (2)

Adjusted

95%

Queue (3)

Existing Conditions

EB Left-Turn 1 300’ 355 287 371 300 254 212 283 NA (4)

EB Left-Turn/Through/Right-Turn (shared) 1 780’ 333 260 354 366 237 156 234 NA (4)

EB Right-Turn 1 780’ 330 221 307 366 235 147 221 NA (4)

Existing Plus Phase One Project Conditions

EB Left-Turn 1 300’ 355 286 371 300 257 216 288 NA (4)


EB Right-Turn 1 780’ 332 224 311 370 237 152 226 NA (4)

Existing Plus Phase Two (Build-Out) Project Conditions

EB Left-Turn 1 300’ 355 270 369 300 263 222 293 NA (4)


EB Right-Turn 1 780’ 375 254 367 428 261 175 253 NA (4)

Notes: (1)

Peak hour volume per lane is derived from the SYNCHRO calculation worksheets used in this queuing analysis. SYNCHRO includes the peak hour factor (PHF) in the vehicles

per hour per lane (vphpl) calculations (shown as “Lane Group Flow” in the SYNCHRO output worksheets). The PHF factors are included in the queuing analysis calculations but

are taken out to report the volume per lane calculations, this is to provide the “true” volume rather than a factored volume calculation. (2)

Queue lengths in SYNCHRO are expressed in feet. (3)

The 95th

percentile queue lengths in SYNCHRO were adjusted where queue lengths exceeded the length of the left turn lane (300 feet), which is constructed as a turn bay.

Since the center and right turn lanes extend for the full length of the off-ramp (780 feet), any reported left-turn lane queues exceeding 300 feet would spill back into the

center lane, which also allows left turn movements. The reported left-turn queue lengths beyond 300 feet were added to the center lane, and the queue lengths of the center

and right-turn lanes were averaged to reflect balanced queue lengths since the center lane allows both left and right turn movements. This adjustment provides more

conservative and accurate queue lengths for the three intersection approach lanes, and account for queues spilling back in the two off-ramp lanes upstream from the

intersection. (4)

NA = Not Applicable. Reported 95th

percentile queue lengths were not adjusted where the left-turn queue length is 300 feet or less.



Table 39. Peak Hour Intersection Queuing Analysis Twin Oaks Valley Road / SR-78 Eastbound Ramps (Year 2016 /

Year 2020 Cumulative Conditions)


#

Lanes

Length

(feet)


Volume

Per

Lane (1)

Reported

50%

Queue (2)

Reported

95%

Queue (2)

Adjusted

95%

Queue (3)

Volume

Per

Lane (1)

Reported

50%

Queue (2)

Reported

95%

Queue (2)

Adjusted

95%

Queue (3)


EB Left-Turn 1 300’ 387 273 384 300 283 224 304 300

EB Left-Turn/Through/Right-Turn (shared) 1 780’ 423 327 472 472 291 217 310 295

EB Right-Turn 1 780’ 411 263 388 472 291 188 276 295

Year 2016 Cumulative Conditions With Project (Phase One)

EB Left-Turn 1 300’ 387 272 384 300 283 221 304 300


EB Right-Turn 1 780’ 413 264 391 478 291 187 277 305


EB Left-Turn 1 300’ 387 258 372 300 283 212 304 300


EB Right-Turn 1 780’ 444 281 422 521 324 210 316 348

Year 2020 Cumulative Conditions With Project (Phase Two Build-Out)

EB Left-Turn 1 300’ 387 254 366 300 283 204 304 300


EB Right-Turn 1 780’ 480 314 470 572 351 228 354 404

Notes: (1)

Peak hour volume per lane is derived from the SYNCHRO calculation worksheets used in this queuing analysis. SYNCHRO includes the peak hour factor (PHF) in the vehicles

per hour per lane (vphpl) calculations (shown as “Lane Group Flow” in the SYNCHRO output worksheets). The PHF factors are included in the queuing analysis calculations but

are taken out to report the volume per lane calculations, this is to provide the “true” volume rather than a factored volume calculation. (2)


The 95th






intersection.



Table 40. Peak Hour Intersection Queuing Analysis Twin Oaks Valley Road / SR-78 Eastbound Ramps (Horizon Year 2030 Conditions)


#

Lanes

Length

(feet)


Volume

Per

Lane (1)

Reported

50%

Queue (2)

Reported

95%

Queue (2)

Adjusted

95%

Queue (3)

Volume

Per

Lane (1)

Reported

50%

Queue (2)

Reported

95%

Queue (2)

Adjusted

95%

Queue (3)

Horizon Year 2030 Conditions Without Project

EB Left-Turn 1 300’ 564 467 715 300 384 298 443 300


EB Right-Turn 1 780’ 521 388 627 859 362 238 369 490

Horizon Year 2030 With Project (Phase Two Build-Out)

EB Left-Turn 1 300’ 564 471 723 300 408 324 443 300


EB Right-Turn 1 780’ 559 447 707 940 378 255 369 490

Horizon Year 2030 With Project (Phase Two Build-Out) - With Mitigation

EB Left-Turn 1 300’ 439 356 556 300 305 235 329 300


EB Right-Turn 1 780’ 406 329 457 641 282 207 263 305

EB Right-Turn (Mitigation for Project Impact) 1 300' 406 329 457 300 282 207 263 300

Notes: (1)

Peak hour volume per lane is derived fromthe SYNCHRO calculation worksheets used in this queuing analysis. SYNCHRO includes the peak hour factor (PHF) in the vehicles per

hour per lane (vphpl) calculations (shown as “Lane Group Flow” in the SYNCHRO output worksheets). The PHF factors are included in the queuing analysis calculations but are

taken out to report the volume per lane calculations, this is to provide the “true” volume rather than a factored volume calculation. (2)


The 95th






intersection.

Note: Queue lengths exceeding total length of off-ramp lanes are indicated in bold.



Table 40 shows that under Horizon Year 2030 conditions without and with the project, the a.m. peak

hour 95th percentile queue lengths of the center and right-turn lanes are forecast to exceed the

total lengths of the two off-ramp lanes, based on the adjusted queue lengths. The adjusted 95th

percentile queue lengths in the two off-ramp lanes are forecast to spill back into the auxiliary lane

and one of the mainline freeway lanes. As shown in Table 40, the recommended mitigation

measure will reduce the adjusted 95th percentile queue length to less than the total length of the

off-ramp lanes. Therefore, the recommended additional right-turn lane will also mitigate the

queuing impacts to the freeway in addition to mitigating the identified significant impact at the

intersection with Twin Oaks Valley Road.

Caltrans Analysis Summary

The ILV methodology of intersection analysis indicated that the ramp intersections are forecast to

operate at Capacity without and with the project from Year 2016 through year 2030. To determine

significant impacts at the ramp intersections, the HCM methodology is used. As presented earlier in

this report, significant impacts were identified at the intersection of Twin Oaks Valley Road / SR-78

Eastbound Ramps under all analysis scenarios with the proposed project.

The results of the peak hour freeway segment analysis show that the addition of project-generated

traffic to freeway segments operating at deficient levels of service would not result in significant

impacts under any of the study scenarios since the forecast reduction in speed is less than 1.0 mph.

Speed and density calculations cannot be made when the freeway segment is operating at LOS F,

which occurs with the existing freeway capacity on SR-78. By 2030, all study freeway segments are

forecast to operate at LOS E or better during the peak hours.

The results of the ramp metering analysis show that under Horizon Year conditions, the addition of

project-related traffic to the Twin Oaks Valley Road / SR-78 Eastbound On-Ramp during the p.m.

peak hour is forecast to result in a ramp meter delay that exceeds the policy threshold of 15minutes.

The increase in ramp meter delay associated with project-related traffic is forecast to result in an

increase in delay that exceeds the significant impact threshold of 2 minutes according to the

SANTEC/ITE TIS Guidelines.

As previously discussed, the existing ramp meter flow rates were used for all future analysis

scenarios. This assumption provided a conservative analysis because there are planned capacity

improvements on eastbound SR-78 through the study area that would likely allow for adjustments in

the future ramp meter rate at the Twin Oaks Valley Road Eastbound On-Ramp.

The planned freeway improvements for eastbound SR-78 through the study area are listed below:

• One new auxiliary lane will be provided, extending from immediately upstream of the San

Marcos Boulevard On-Ramp and connecting with the existing auxiliary lane that is currently

provided from the San Marcos Boulevard eastbound on-ramp to the Twin Oaks Valley Road

eastbound off-ramp. 101

• A second eastbound auxiliary lane will be provided that will begin at the San Marcos Boulevard

eastbound on-ramp and will terminate at the Twin Oaks Valley Road eastbound off-ramp. The

first auxiliary lane will be extended east though the Twin Oaks Valley Road interchange and will

terminate at the Woodland Parkway/Barham Drive eastbound off-ramp.



• The lengths of the San Marcos Boulevard and Twin Oaks Valley Road eastbound on-ramps would

be increased to provide longer acceleration and merging distances from the ramp meters to the

freeway ramp gore points.

• A new eastbound auxiliary lane will be provided from the reconfigured Barham Drive/Woodland

Parkway interchange that will extend east to connect with the existing auxiliary lane that

currently begins immediately east of the SPRINTER overcrossing.

The improvements listed above are planned to be completed prior to the year 2030 and are

included in the Horizon Year 2030 conditions analysis.

The existing ramp meter flow rate of 570 vehicles per hour during the p.m. peak period equates to

approximately 9.5 cycles per minute at the Twin Oaks Valley Road Eastbound On-Ramp. Based on

the existing p.m. ramp meter rate, the forecast ramp meter delay is 17 minutes under Horizon Year

2030 conditions with the proposed project. If the p.m. ramp meter flow rate were adjusted slightly

to 600 vehicles per hour, the forecast ramp meter delay under 2030 conditions with the project

would decrease to 13 minutes, which is equivalent to the forecast p.m. ramp meter delay without

the project. The adjustment to 600 vehicles per hour is equivalent to 10 cycles per minute, a

difference of only one-half cycle per minute.

This adjustment in the p.m. ramp meter rate should be feasible based on the expected improvement

in freeway operations when the planned improvements are completed. Therefore, it is reasonable

to expect that the planned improvements along eastbound SR-78 would reduce the identified ramp

meter impact to a level that is less than significant, and no mitigation measures would be required.

deficient ramp meter delay under Horizon Year 2030 conditions. Therefore, the project results in a

significant impact at the Twin Oaks Valley Road / SR-78 Eastbound On-Ramp and mitigation

measures are required (Impact TR-3). There are two options to reduce this impact to below a level

of significance:



• Adjusting the ramp meter rate to accommodate the increase in demand at

the on-ramp; or

• Converting the existing HOV lane to a third SOV lane on the on-ramp to

increase on-ramp capacity.

•

Implementation of mitigation measure MM-TR-3, which will be required as a condition of project

approval will reduce the deficient ramp meter delay under the Horizon Year 2030 conditions at the

Twin Oaks Valley Road / SR-78 Eastbound On-Ramp during the p.m. peak hour to below a level of

significance.

The results of the queuing analysis for the eastbound off-ramp at Twin Oaks Valley Road show that

the Horizon Year 2030 queuing impacts to the eastbound freeway lanes will be mitigated by the

recommended additional right-turn lane at the eastbound (off-ramp) intersection approach at Twin

Oaks Valley Road (MM-TR-1).



c) Result in a change in air traffic patterns, including either an increase in traffic levels or a

change in location that results in substantial safety risks? No Impact

The project site is located approximately six miles east of McClellan-Palomar Airport. Given the type

of development proposed (residential and open space preservation), as well as the project’s

distance from the airport, the project will not result in a change in air traffic patterns. Therefore, no

impacts are identified for this issue area.

d) Substantially increase hazards due to a design feature (e.g., sharp curves or dangerous

intersections) or incompatible uses (e.g., farm equipment)? No Impact

The roadways designed for this project do not have any sharp curves, nor do they create dangerous

intersection. Two traffic circles to facilitate traffic flows are proposed along the Backbone Road and

another traffic circle is considered for the future intersection of Village Drive North/Carnation

Court/project road. Traffic circles would not be characterized as a design that would substantially

increase hazards or incompatible uses. Therefore, no impact is identified for this issue area.

e) Result in inadequate emergency access? Less Than Significant Impact

The project provides adequate emergency access. Street widths meet the requirements of the San

Marcos Fire Department and there are two ways into the residential community. Construction of the

proposed project will not result in the closure of any roads that would impede emergency access.

Therefore, impacts are less than significant.

f) Result in inadequate parking capacity? Less Than Significant Impact

The project is a new development and does not remove any existing parking on the project site or in

the project vicinity. Each residential unit will have either front-loaded or alley-loaded garage

parking. In addition to the garage parking for each unit, there will be 299 on-street parking spaces

spread across the residential development area. The future park and non-residential multi use

development will also be required to have adequate parking. Therefore, the project will not result in

inadequate parking capacity and impacts are less than significant.

g) Conflict with adopted policies, plans, or programs supporting alternative transportation (e.g.,

bus turnouts, bicycle racks)? No Impact

Existing and Future Bicycle and Pedestrian Access

Class II bike lanes are currently provided on both sides of Twin Oaks Valley Road through the project

study area and along the project frontage. Bike lanes will be provided on the proposed “Backbone

Road”, which will provide access to both Craven Road and Twin Oaks Valley Road from the proposed

project site. The “Backbone Road” will also provide bicycle access to the adjacent proposed school

from existing neighborhoods that access Santa Barbara Drive, thus providing a shorter, more direct

route to the school from those neighborhoods. There are currently bike lanes on both sides of the

street on North Village Drive, and the extension of North Village Drive to the “Backbone Road” will

include the extension of the bike lanes.

Pedestrian access to the proposed project site would be provided from Santa Barbara Drive

(existing), North Village Drive (existing), and South Village Drive (future). Along Twin Oaks Valley



Road north of North Village Drive, there is currently an 8-foot sidewalk on the west side of the

street. Between North Village Drive and South Village Drive, there is currently a narrow unpaved

footpath provided along the west side of Twin Oaks Valley Road, which is along the project frontage.

Phase Two of the proposed project will include construction of a sidewalk along the west side of

Twin Oaks Valley Road.

Sidewalks will be constructed along the extensions of Santa Barbara Drive and North Village Drive

under Phase One of the proposed project. Continuous pedestrian access will ultimately be provided

between Santa Barbara Drive and the Twin Oaks Valley Road / South Village Drive intersection when

the “Backbone Road” is completed under Phase Two. The “Backbone Road” will also provide

pedestrian access to the adjacent non-residential mixed use site from both the proposed project site

and the existing neighborhoods near Santa Barbara Drive.

In summary, the project will enhance bicycle and pedestrian transportation options in the project

area, therefore no impact is identified.

Existing and Future Transit Access

There is currently no transit service along Twin Oaks Valley Road south of Craven Road, and future

transit service is not anticipated to be provided within a reasonable walking distance of the

proposed project. The nearest transit stop is located on Craven Road near the intersection with

Rush Drive, which is located approximately between one-half and three-fourths of a mile from the

proposed project site. This transit stop serves Breeze Route 347, which provides transit service

between Palomar Community College and CSU San Marcos. The project does not propose any uses

that would conflict with existing transit options, therefore no impact is identified.

XVII. UTILITIES AND SERVICE SYSTEMS

A Water and Sewer Study was prepared for the project by Vallecitos Water District (2014). The

complete report is included as Appendix N of this document.

a) Exceed wastewater treatment requirements of the applicable Regional Water Quality Control

Board? Less than Significant Impact

The project will not exceed wastewater treatment requirement of the applicable Regional Water

Quality Control Board. Impacts are less than significant.

b) Require or result in the construction of new water or wastewater treatment facilities or

expansion of existing facilities, the construction of which would cause significant

environmental effects. Less than Significant Impact

Water Facilities Analysis

Water Distribution Infrastructure Analysis – The project is within the boundaries of the Vallecitos

Water District (VWD) for water service and is within the 920 Pressure Zone. Water service will be

connected to the existing 14-inch South Lake Pump Station inlet approximately 800 feet west of the

intersection of Twin Oaks Valley Road and Village Drive. The project includes the necessary utility

improvements to support the proposed development and includes approximately 15,360 linear feet

of water lines. An existing 14 inch Vallecitos Water District water main will be relocated. Water



modeling prepared by VWD concluded that the project would not create any new distribution

system deficiencies under average day demand, maximum day demand, and peak hour demand

conditions. No system deficiencies were identified under maximum day plus fire flow demand

conditions. Therefore, the project will have a less than significant impact related to water

distribution infrastructure.

Water Storage Analysis – The VWD 2008 Master Plan assumed water demand on the site would be

268,550325,562 gallons per day (gpd). Under the proposed development, the project would have a

water demand of 269,884 253,745 gpd. This represents an increasea decrease of approximately

1,334 71,817 gpd (Table 41).

Table 41. Rancho Coronado Estimated Water Demand

Land Use Type

Area

(acres)

Number of

Residential Units

Duty Factor

(gpd/acre)

Water Demand

(gpd)

2008 Master Plan Land Use Demand

Residential

(.125 to 1.0 du/acre) 96.78 --- 600 58,068

Residential

(2-4 du/acre) 91.62 --- 1,800 164,916

Parks/Golf Courses 60.34 --- 1,700 102,578

TOTAL 248.74 325,562

Proposed Project

Residential

(4-8 du/acre) 50.95

346 single family

(high-efficiency) 2,500 127,375

Parks/Golf Courses 38.60 --- 1,700 65,620

Open Space 129.29 --- 200 25,858

Commercial

(Business Park) 22.24 --- 1,500 33,360

Right-of-Way 7.66 --- 200 1,532

TOTAL 248.74 --- --- 253,745



Table 41. Rancho Coronado Estimated Water Demand

Land Use Type

Area

(acres)

Number of

Residential Units

Duty Factor

(gpd/acre)

Water Demand

(gpd)


Residential

(0.05 – 0.25 du/acre) 83.6 --- 1,000 83,600

Residential

(1-2 du/acre) 14.9 --- 1,200 17,880

Residential

(2-4 du/acre) 63.3 --- 1,800 113,940

Industrial 39.0 --- 1,000 39,000

Recreational 2.5 --- 1,700 4,250

Open Space 49.4 --- 200 9,800

TOTAL 252.7 268,550

Proposed Project

Residential

(4-8 du/acre) 58.1

346 single family


Non-Residential

Mixed Use

(Business Park/Retail)

22.24 --- 1,500 33,360

Parks 38.48 --- 1,700 65,416

Open Space 129.29 --- 200 25,858

TOTAL 248.01 --- --- 269,884

Note:

(1) CEQA analysis assumed 240,000 s.f. of development within the non-residential mixed use area with 90% being

business/office park and 10% being retail.

Potable water storage within VWD is sized for operational, emergency, and fire flow storage. Since

the project does not increase the water demand above what was projected for the project site in

the 2008 Master Plan, the storage requirement to serve the project has already been included in the

2008 Master Plan CIP infrastructure and no further storage upgrades are required. Therefore

impacts are less than significant.

This increase in water demand will result in increase of potable water storage demand capacity by

6,670 gallons. The project will pay Water Capital Facility Fees per VWD Ordinance No. 175. This

requirement is also noted in Table 2. These fees will be used by VWD to expand water storage

facilities, as needed, within their service area. VWD considers payment of the Water Capital Facility

Fees as mitigation for the increase in water storage demand. Therefore, impacts are less than

significant.

Water Pump Station Analysis - Pump stations are sized to supply minimum day flows while meeting

all pressure criteria within their service area. Since the proposed project is located in a pressure

zone that is not served by pumping, there are no pump station requirements for the project. Thus,

no impact is identified related to water pump stations.



Wastewater Facilities Analysis

The project site lies completely within VWD sewer shed 36C. A ten-inch sewer line exists to the east

of the project site within Twin Oaks Valley Road and an 8-inch sewer line exists north of the project

site at the intersection of Orchid Avenue and Santa Barbara Drive.

Currently, the project site is not within VWD’s sewer district boundaries and the entire project site

must be annexed to be eligible for sewer service. This is an intra-district annexation and does not

require Local Agency Formation Commission (LAFCO) approval or process.

Table 42. Rancho Coronado Estimated Wastewater Flows

Land Use Type

Area

(acres)

Number of

Residential Units

Duty Factor

(gpd/acre)

Wastewater Flow

(gpd)


Residential

(.125 to 1.0 du/acre) 96.78 --- 150 14,517

Residential

(2-4 du/acre) 91.62 --- 750 68,715

Parks/Golf Courses 60.34 --- 250 15,085

TOTAL 248.74 98,317

Proposed Project

Residential

(4-8 du/acre) 50.95

346 single family


Parks/Golf Courses 38.60 --- 250 9,650

Open Space 129.29 --- 40 5,172

Commercial

(Business Park) 22.24 --- 1,200 26,688

Right-of-Way 7.66 --- 0 0

TOTAL 248.74 --- --- 107,745

VWD’s 2008 Maser Plan assumed a wastewater generation of 95,145 gpd for the project site. Under

the proposed project, the wastewater generation is anticipated to be 117,010 107,745 gpd. This

represents an increase of 21,865 9,428 gpd (Table 42).

Wastewater Collection System Analysis - Increased generation of wastewater from the project

would impact the sewer collection infrastructure in the direct vicinity of the project as well as the

downstream infrastructure to Lift Station No. 1 on San Marcos Boulevard. Modeling prepared by

VWD determined that the 8-inch collection pipe in Craven Road is projected to be undersized from

Santa Barbara Drive to approximately 575 feet south of Discovery Street. This would occur under

the ultimate buildout conditions, even without the proposed project’s increased flows. For ultimate

buildout, the VWD 2008 Master Plan identifies approximately 2,700 feet of 8-inch pipeline to be

replaced with 700 feet of 10-inch pipeline and 2,000 feet of 12-inch pipeline as part of CIP #24 for

construction between the years 2021 and 2025. This CIP is to be completed funded by development

without contribution from the VWD capacity fund. The additional wastewater flows from the project

do not result in any other new deficiencies under peak wet weather flows during ultimate build-out

conditions.



The project will upsize this off-site segment of sewer line per the requirements of VWD. The upsizing

will be only to accommodate flows from the proposed project. This will ensure impacts are less than

significant.

Wastewater Life Station Analysis - Lift stations are sized for peak wet weather flow. Since the

project site is not located in a sewer shed that is served by a lift station (Lift Station No. 1 is a

stripping station and does not meet this definition) or requires a lift station, there are no lift station

upgrade requirements for the project. Thus no impact is identified.

Parallel Land Outfall Analysis - VWD’s existing outfall is approximately eight miles in length and

consists of four gravity pipeline sections and three siphon sections varying from 20 to 54 inches.

VWD maintains the entire pipeline from Lift Station No. 1 to the Encina Pollution Control Facility

(EWPCF).

VWD is currently considering two scenarios for increasing increased wastewater flows from planned

development within their service area. The first option is constructing a peak flow storage area near

Lift Station No. 1. The second option is to convey peak flows to the EWPCF through a parallel land

outfall.

The project will pay Wastewater Capital Facility Fees per VWD Ordinance No. 176 and Wastewater

Density Impact Fees per VWD Ordinance 177. This requirement is also noted in Table 2. These fees

will be used by VWD to help fund the parallel land outfall expansion. VWD considers payment of the

fees as mitigation for the increase in the need for land outfall capacity. Therefore, impacts are less

than significant.

Wastewater Treatment Facility Analysis - VWD uses two wastewater treatment facilities to treat

wastewater that is collected within its sewer service area: the MRF and the EWPCF. The project will

increase the wastewater flows from the project site by approximately 21,8659,428 gpd. VWD is

already projected to experience ultimate solids handling, liquids handling and ocean disposal

capacity deficiencies.

The project will pay Wastewater Capital Facility Fees per VWD Ordinance No. 176 and Wastewater

Density Impact Fees per VWD Ordinance 177. This requirement is also noted in Table 2. These fees

will be used by VWD to help fund the expansion and/or construction of wastewater treatment

facilities to handle increase wastewater quantities. VWD considers payment of the fees as

mitigation for the increase in treatment need. Therefore, impacts are less than significant.

c) Require or result in the construction of new storm water drainage facilities or expansion of

existing facilities, the construction of which could cause significant environmental effects?


The project proposes a comprehensive stormwater management plan that includes stormwater

improvements within the project boundary. This includes bio-retention features that will detain and

retain stormwater flows from the pads and roads. These features have been sized to accommodate

stormwater flows, as detailed in the WQIP (Appendix J) and the Hydrology report (Appendix I) for

the project.



The project includes approximately 11,198 linear feet of storm drains. Construction of these

facilities is proposed within the development footprint for the project. An expansion of existing

facilities will not be required to serve the project. Therefore, impacts are less than significant.

d) Have sufficient water supplies available to serve the project from existing entitlements and

resources, or are new or expanded entitlements needed? Less than Significant Impact

The VWD 2008 Master Plan assumed water demand on the site would be 268,550 325,562 gallons

per day (gpd). Under the proposed development, the project would have a water demand of

269,884 253,745 gpd. This represents an increasea decrease of approximately 71,817 1,334 gpd

(Table 41). Since the project does not increase the water demand above what was projected for the

project site in the 2008 Master Plan, the storage requirement to serve the project has already been

included in the 2008 Master Plan CIP infrastructure and no further storage upgrades are required.

Therefore impacts are less than significant. The minor increase in water demand would not be

characterized as significant from a supply perspective and impacts would be less than significant,

e) Result in a determination by the wastewater treatment provider, which serves or may serve

the project that it has adequate capacity to serve the project’s projected demand in addition

to the provider’s existing commitments? Less than Significant Impact

As analyzed in Section XVII.b., due to changes in the type of development assumed for the project

site, the project will increase the demand for wastewater treatment as well as land outfall capacity.

As noted in Section XVII.b, the project will pay Wastewater Capital Facility Fees per VWD Ordinance

No. 176 and Wastewater Density Impact Fees per VWD Ordinance 177. This requirement is also

noted in Table 2. These fees will be used by VWD to help fund the expansion and/or construction of

wastewater treatment facilities to handle increase wastewater quantities and also the expansion of

land outfall facilities. VWD considers payment of the fees as mitigation for the increase in treatment

need. Therefore, impacts are less than significant.

f) Be served by a landfill with sufficient permitted capacity to accommodate the project’s solid

waste disposal needs? Less than Significant Impact

Solid waste service in the City is provided by a private franchise hauler, EDCO Waste and Recycling

(EDCO), which handles all residential, commercial and industrial collections within the City. Waste

collected is then hauled to the Palomar Transfer Station in Carlsbad where it is then transported to

the Sycamore Sanitary Landfill in Santee.

The Escondido Transfer Station accepts mixed municipal waste, green materials, and

construction/demolition materials. It has a daily capacity of 2,500 tons with a permitted capacity of

3,402 tons/day. The Sycamore Sanitary Landfill has a daily permitted capacity of 3,965 tons/day of

solid waste, with an anticipated closure date of 2031 (CalRecycle 2013).

CalRecycle provides solid waste generation rates for various types of land uses. Construction and

demolition debris would be generation by the project through removal of the existing industrial

buildings and parking pavement. Construction and demolition debris recycling is available through

EDCO.

Based upon typical industry generation rates, the project is expected to generate approximately

795 tons/year or 2.1 tons/day (see table below.) This does not consider any waste diversion through



recycling. It is expected that 50 percent of this total volume will be diverted from the landfill

through recycling, thus the volume going to the landfill is expected to be 397.5 tons/year or

1.05 tons/day.

Land Use

Generation

Rate

Units/s.f.

Proposed

Total Volume

(tons/year)

Residential 0.44/tons/DU/year 346 units 219

Commercial 0.0024 tons/s.f./year 240,000 s.f. 576

Total 795(1)

Source: CalRecycle estimated solid waste generation rates (1)

This does not include any diversion through recycling

DU = dwelling unit

s.f. = square feet

Currently, approximately 2,380 tons of waste enter the Sycamore Canyon Landfill each day (City of

San Diego 2013). Therefore there is approximately 1,585 tons/day of capacity at the landfill. Thus,

the project’s contribution of 1.5 tons/day would be a less than significant impact.

g) Comply with federal, state, and local statutes and regulations related to solid waste? No

Impact

The project will comply with all federal. State and local statutes and regulations related to solid

waste, including proper handling of construction and demolition debris. Thus no impact is identified

for this issue area.



V. MANDATORY FINDINGS OF SIGNIFICANCE

The following are Mandatory Findings of Significance in accordance with Section 15065 of the CEQA

Guidelines.

a) Does the project have the potential to degrade the quality of the environment, substantially

reduce the habitat of a fish or wildlife species, cause a fish or wildlife population to drop below

self-sustaining levels, threaten to eliminate a plant or animal community, reduce the number or

restrict the range of a rare or endangered plant or animal or eliminate important examples of the

major periods of California history or prehistory? Less Than Significant Impact With Mitigation

Incorporated

Potential impacts to biological resources were analyzed in the document (Section 3.4). A biological

resources report was prepared for the project by HELIX (2014). Based upon the requirements of the

existing Habitat Loss Permit for the project site, mitigation measures MM-BIO-A through MM-BIO-G

are included for the project. Potential direct and indirect impacts to sensitive species will be

mitigated through the implementation of mitigation measures which will be required as a condition

of project approval (MM-BIO-1 through MM-BIO-4). These measures include avoidance during

nesting season, preconstruction surveys, and measures to reduce indirect impacts. These measures

also require habitat conservation, enhancement and creation. The project will implement a riparian

restoration plan (MM-BIO-1B) to mitigate for impacts to riparian habitat and jurisdictional wetlands

and waters. Preserved areas would be outside the 150-foot fuel modification buffer. The project will

also be required to secure permits from the regulatory agencies (USACE, CDFW and RWQCB) for

impact to jurisdictional waters and wetlands. Impact to biological resources will be mitigated to

below a level of significance.

Cultural resources were analyzed in Section 3.5 of this document. A cultural resources report was

prepared for the project by ASM (2013). The cultural resources records search and site visit did not

identify any cultural resources on the site. The cultural resources report did recommend monitoring

during grading in the event that unidentified cultural resources are encountered during project

grading. Implementation of mitigation measures (MM-CR-1 through MM-CR-8) will be required as a

condition of project approval and will this potential impact to below a level of significance.

Monitoring will reduce the potential for impact to eliminate important examples of the major

periods of California history or prehistory to below a level of significance.

Therefore, this project has been determined not to meet this Mandatory Finding of Significance and

impacts are less than significant with the incorporation of mitigation.

b) Does the project have impacts that are individually limited, but cumulatively considerable?

("Cumulatively considerable" means that the incremental effects of a project are considerable

when viewed in connection with the effects of past projects, the effects of other current projects,

and the effects of probable future projects.) Less Than Significant Impact With Mitigation

Incorporated

Cumulative impacts related to traffic, air quality and noise were analyzed in this CEQA document.

Based upon the analysis, the project will not have any cumulative impact related to air quality and

noise. The project will contribute to a cumulative traffic impact in the Horizon Year 2030 time



frames. Mitigation measures MM-TR-1 and, MM-TR-2 and MM-TR-3 will reduce the impact to below

a level of significance. The project will be required to pay a fair share for improvements to reduce

the impacts to below a level of significance.

All other impacts were site-specific (e.g., cultural resources and hazards/hazardous materials) and

will not result in a significant cumulative impact. Therefore, this project has been determined not to

meet this Mandatory Finding of Significance and impacts are less than significant with the

incorporation of mitigation.

c) Does the project have environmental effects, which will cause substantial adverse effects on

human beings, either directly or indirectly? Less Than Significant Impact With Mitigation

Incorporated

In the evaluation of environmental impacts in this Initial Study, the potential for adverse direct or

indirect impacts to human beings were considered in the response to certain questions in

Sections I. Aesthetics, III. Air Quality, VI. Geology and Soils, VII. Hazards and Hazardous Materials,

VIII. Hydrology and Water Quality, XII. Noise, XIII. Population and Housing, and XVI. Transportation

and Traffic. As a result of this evaluation, there is no substantial evidence that there are adverse

effects on human beings associated with this project.

The Aesthetics analysis concluded that the project would result in a visual change to the project site

but that the change would be less than significant due to the incorporation of grading, landscape

and architectural design requirements identified in the Residential Design Guidelines and the

Specific Plan.

The Air Quality analysis concluded that emissions associated with project construction and

operation would be less than significant. The project will implement dust control measures during

construction and also use low-VOC coatings as required by SDAPCD Rule 67.0. These requirements

are included as design features.

The Geology and Soils analysis concluded that the project would have a less than significant impact.

Recommendations identified in the geotechnical report prepared for the project would be

implemented and these requirements were identified in summary of project design features

(Table 2).

The Hazards and Hazardous materials analysis concluded that impacts would be less than significant,

including hazards related to wildland fire. As a condition of project approval, the project will be

required to implement a fire protection plan (MM-HAZ-1). The fire protection plan will be subject to

review and approval by the Fire Marshal.

The Hydrology/Water Quality section determined that impacts would be less than significant. The

design of the project, which includes 2.51 acres of bio-retention features to ensure post-condition

runoff is the same amount and rate as pre-condition runoff. The project also includes self-treating

areas (water quality lots). A comprehensive Water Quality Improvement Plan (Appendix I) to

address potential water quality pollutants that would be generated by the project by Fuscoe

Engineering (2013).



The Noise section addressed both construction related noise (including blasting and rock crushing)

as well as operational noise. Mitigation measure MM-N-4 will be implemented to reduce potential

noise impacts associated with proposed rock crushing To minimize noise onsite from traffic, noise

barriers ranging from five to six feet will be required for the future homes on North Village Drive and

barriers ranging from six to ten feet will be required for rear yard areas that are adjacent to Twin

Oaks Valley Road (MM-N-1). Additionally, noise measurements for interior second story areas will

also be required (MM-N-2) and implementation of architectural treatments would be required if

interior noise levels are anticipated to be elevated. Finally, if outdoor usable areas are incorporated

into the future non-residential mixed use area, the design shall consider shielding and setback to

meet required noise levels (MM-N-3). Implementation of these noise mitigation measures, which

will be required as condition of project approval would reduce impacts to below a level of

significance.

The Population and Housing section growth inducement and displacement of people and housing.

Impacts were determined to be less than significant.

Finally, the Transportation and Traffic section concluded that the project will contribute to a

cumulative traffic impact in the Horizon Year 2030 Conditions time frame. Mitigation measures

MM-TR-1 and, MM-TR-2 and MM-TR-3 will reduce the impact to below a level of significance. The

project will be required to pay a fair share for improvements to reduce the impacts to below a level

of significance.

In summary, all impacts in these environmental issue areas are less than significant or mitigated to

below a level of significance. Therefore, this project has been determined not to meet this

Mandatory Finding of Significance and impacts are less than significant with the incorporation of

mitigation.



VI. PERSONS AND ORGANIZATIONS CONSULTED

This section identifies those persons who prepared or contributed to preparation of this document. This

section is prepared in accordance with Section 15129 of the CEQA Guidelines.

A. CITY OF SAN MARCOS

Jerry Backoff, Planning Director

Garth Koller, Project Planner

Peter Kuey, Principal Civil Engineer

Susan Vandrew Rodriguez, Associate Planner

Matthew Ernau, Fire Division Chief/Fire Marshal

B. CONSULTANTS

CEQA Documentation

Sophia Mitchell & Associates

Sophia Habl Mitchell, LEED AP

Air Quality

Scientified Resourcs Associated

Valorie Thompson, Principal

Cultural Resources

ASM Affiliates

Shelby Castells, M.A., RPA

Nicholas Hanten, B.S.

Sinéad Ní Ghabhláin, Ph.D., RPA

Noise

LdN Consulting

Jeremy Louden, Principal

Traffic

RBF Consulting

David Mizell, Traffic Engineer



VIII. REFERENCES

ASM Affiliates. 2013. Cultural and Historical Resources Survey Report for the Rancho Coronado Specific

Plan Project, City of San Marcos, San Diego County, California. November.

CalRecycle. 2013. Solid Waste Information System – Escondido Resource Recovery.

http://www.calrecycle.ca.gov/SWFacilities/Directory/37-AA-0906/Detail/ Viewed November

18, 2013.

CalRecycle. 2013. Solid Waste Information System – Sycamore Sanitary Landfill.

http://www.calrecycle.ca.gov/SWFacilities/Directory/37-AA-0023/Detail/ Viewed November 18,

2013.

California Department of Toxic Substance Control. Envirostor Database.

http://www.envirostor.dtsc.ca.gov/ Viewed January 23, 2014

Chang Consultants. 2007. Breach Study for South Lake and Development of Inundation Map for

Downstream Channel in the City of San Marcos. September.

City of San Marcos Fire Department. 2013. Letter to Sophia Habl Mitchell regarding fire protection

services from Fire Marshal Matthew Ernau. November 18.

County of San Diego Sheriff’s Department. 2012. E-mail correspondence from Corporal Malcolm Horst to

Susan Vandrew Rodriguez. September 20, 2012.

County of San Diego Sheriff’s Department. 2013. E-mail correspondence from Corporal Malcolm Horst to

Sophia Habl Mitchell. December 3, 2013.

Fusco Engineering. 2013. Preliminary Water Quality Improvement Plan Sheets. Rancho Coronado South.

December 5.

Geosyntec. 2013a. Letter report address to Craig Burnett at County of San Diego, Department of

Environmental Health Site Assessment and Mitigation Program. “Summary of Results, Additional

Soil Characterization Lehigh Hanson Property, San Marcos, California.” June 4.

Geosyntec. 2013b. Native Background Arsenic Summary. Former Hanson Aggregate San Marcos Plant,

San Marcos, California.

Helix Environmental. 2014. Rancho Coronado Biological Technical Report. January 20.

LdN Consulting. 2014. Noise Assessment Rancho Coronado Specific Plan. January 28.

RBF Consulting. 2014. Hanson Rancho Coronado Traffic Impact Analysis Report. January 30.

San Marcos Unified School District (via Bowie Arneson, Wiles & Giannone). 2012. Letter from Alexander

Bowie to Sophia Habl Mitchell. August 31.



Scientific Resources Associates. 2014a. Air Report for the Rancho Coronado Specific Plan. January 29.

Scientific Resources Associates. 2014b. Global Climate Change Assessment for the Rancho Coronado

Specific Plan. January 29.

SCS Engineers. 2012. Phase I Environmental Site Assessment. Rancho Coronado Villages Project South

Twin Oaks Valley Road and Village Drive. January 30.

Vallecitos Water District. 2014. Rancho Coronado Villages Water and Sewer Study. February 27.



IX. MITIGATED NEGATIVE DECLARATION

City of San Marcos

The following Mitigated Negative Declaration is being circulated for public review in accordance with

the California Environmental Quality Act Section 21091 and 21092 of the Public Resources Code.

Public Review Period: February 5, 2014 to March 7, 2014

Project Name: Heart of the City Specific Plan Amendment (Rancho Coronado)

Project Applicant: Lehigh Hanson West Region, PO BOX 639069, San Diego, CA 92613-9069

Project Location: The 248-acres project site is located within the southwestern portion of the Heart

of the City Specific Plan. The project site property is bounded by Twin Oaks Valley Road on the east,

the Discovery Hills residential community on the north, and undeveloped land on the west and

south in the Barham/Discovery Hills neighborhood. The project site coincides with the former

Hanson mining site. The eastern and northern portions of the former Hanson mining site are

disturbed from past aggregate mining activities and the remainder of the site is vegetated and

undeveloped. The project is proposed in areas that are disturbed from previous mining.

Project Description: The project proposes a Specific Plan amendment to the Heart of the City

Specific Plan. The project would develop 346 residential units, 22.24 acres of non-residential mixed

use (business park), approximately 38 acres of active park and the necessary infrastructure to

support the proposed development. The project also preserves 129.29 acres of open space and

includes a biological mitigation area. Discretionary actions for the project include approval of:

Specific Plan Amendment, and Tentative Subdivision Map.



X. FINDINGS

This is to advise that the City of San Marcos, acting as the lead agency, has conducted an Initial Study

to determine if the project may have a significant effect on the environmental and is proposing this

Mitigated Negative Declaration based upon the following findings:

� The Initial Study shows that there is no substantial evidence that the project may have a

significant effect on the environment and a NEGATIVE DECLARATION will be prepared.

� The Initial Study identifies potentially significant effects but:

(1) Proposals made or agreed to by the applicant before this proposed Mitigated Negative

Declaration was released for public review would avoid the effects or mitigate the

effects to a point where clearly no significant effects would occur.

(2) There is no substantial evidence before the agency that the project may have a

significant effect on the environment.

(3) Mitigation measures are required to ensure all potentially significant impacts are

reduced to levels of insignificance. Mitigation proposed for the project includes:

Biological Resources Mitigation Measures

The following project design measures shall be carried forward from the HLP conditions to minimize

impacts to biological resources and are identified as mitigation measures for the project.

Implementation of these mitigation measures will be required as a condition of project approval.

MM-BIO-A The clearing and grubbing of sensitive habitats shall occur outside of the bird

breeding season (February 15 to August 31), unless a qualified biologist

demonstrates to the satisfaction of the City and the Wildlife Agencies that all

nesting is complete. The qualified biologist would need to be federally permitted

for coastal California gnatcatcher if the habitat being cleared has potential to


MM-BIO-B Temporary perimeter fencing shall be installed to separate the proposed

development and the fuel management zones from any CSS areas to the preserved

under the HLP. The removal of temporary fencing is only to occur after all clearing

and construction has been completed.

MM-BIO-C Lots adjacent to biological open space will have permanent fencing and no gates

between the development and the open space; (a) landscaping will be restricted to

native and/or non-invasive plant species; and (b) Best Management Practices

(BMPs) during construction in accordance with Nation Pollutant Discharge

Elimination Systems General Construction Permit requirements will be

implemented.



MM-BIO-D A biological monitor will be on-site when habitat is being cleared, and/or

construction activities are occurring within 100 feet of a Biological Open Space

Easement boundary. Permanent signs must be placed every 100 feet along the

fence bordering the preserve. The signs must be corrosion resistant, no less than

three feet above the ground surface, have minimum dimensions of 6” x 9”, and

must state the following:



By Easement

Information:


MM-BIO-E A conservation easement shall be placed over all on-site mitigation. Additionally,

the applicant shall insure that the biological open space is deeded to a nature

conservancy acceptable to the planning Division Director for maintenance and

monitoring purposes.

MM-BIO-F Manufactured slopes will be revegetated with appropriate native species in

consultation with the Wildlife Agencies. The landscape plan and construction

documents will be approved by the City Engineer, Planning Director, and Fire

Marshal prior to issuance of building permits.

MM-BIO-G Any lands providing mitigation/preservation for the project shall be held in

perpetuity in accordance with a habitat management plan to be approved by the

City and the Wildlife Agencies.

MM-BIO-1A Impacts to 0.23 acre southern riparian forest, 0.15 acre riparian woodland, 1.43

acres southern willow scrub, 0.90 acre freshwater marsh, 0.33 acre mule fat scrub,

and 0.09 SWS/FWM habitat will be mitigated at a 3:1 ratio. Impacts to 0.85 acres

disturbed wetland will be mitigated at a 2:1 ratio. Impact to 0.02 acre streambed

will be mitigated at a 1:1 ratio as detailed in Table 7a for a total of 8.89 acres of

mitigation. Mitigation includes a combination of onsite and offsite creation and

enhancement with 6.47 acres of creation and 0.30 acres of enhancement occurring

onsite and 1.07 1.27 acres creation mitigation credit equivalents and 1.05 acres

enhancement credits at the North County Habitat Bank (NCHB).

MM-BIO-1B The preparation of a riparian restoration plan will be required as a condition of the

mitigation for impacts to riparian vegetation communities. The plan will be require

review and approval by the City and include the following.

• All final specifications and topographic-based grading, planting, and

irrigation plans (0.5-foot contours and typical cross-sections) for the

creation/restoration sites. All wetland mitigation areas shall be graded to

the same elevation as adjacent existing jurisdictional wetlands areas, and/or

to within 1 foot of the groundwater table, and shall be left in a rough grade

state with micro topographic relief (including channels for wetlands) that

mimics natural topography, as directed by the City and Resource Agencies.



All plantings shall be installed in a way that mimics natural plant


• Planting palettes (plant species, size, and number/acre) and seed mix (plant

species and pounds/acre). Unless otherwise approved by the City and

Resource Agencies, only locally native species (no cultivars) obtained from

as close to the project area as possible shall be used. The source and proof

of local nativeness of all plant material and seed shall be provided;

• Container plant survival shall be 80 percent of the initial plantings for the

first year;

• A final implementation schedule that indicates when all riparian/wetland

impacts, as well as riparian/wetland creation/restoration grading, planting,

and irrigation, will begin and end. Necessary site preparation and planting

shall be completed during the concurrent or next planting season (i.e., late

fall to early spring). Any temporal loss of habitat caused by delays in

riparian/wetland habitat creation/restoration shall be offset through like

habitat creation/restoration at a 0.5:1 ratio for every 6 months of delay

(i.e., 1:1 for 12 months delay, 1.5:1 for 18 months delay, etc.). In the event

that the project applicant is wholly or partly prevented from performing

obligations under the final plans (causing temporal losses due to delays)

because of unforeseeable circumstances or causes beyond the reasonable

control, and without the fault of negligence of the project applicant,

including but not limited to natural disasters (e.g., earthquakes, etc.), labor

disputes, sudden actions of the elements (e.g., further landslide activity), or

actions or inaction by federal or state agencies, or other governments, the

project applicant will be excused by such unforeseeable cause(s);

• Five years of success criteria for wetland/riparian creation/restoration

areas, including: separate percent cover criteria for herbaceous understory,

shrub midstory, and tree overstory, and a total percent absolute cover for

all 3 layers at the end of 5 years; evidence of natural recruitment of multiple

species for all habitat types; 0 percent coverage for Cal-IPC’s “Invasive Plant

Inventory” species, and no more than 10 percent coverage for other


• A minimum of 5 years of maintenance and monitoring of riparian/wetland

creation/restoration areas, unless success criteria are met earlier and all

artificial water supply has been off for at least 2 years

• A qualitative and quantitative vegetation monitoring plan with a map of

proposed sampling locations. Photo points shall be used for qualitative

monitoring and stratified-random sampling shall be used for all quantitative

monitoring;

• Contingency measures in the event of creation/restoration failure;

• Annual mitigation maintenance and monitoring reports shall be submitted

to the City and Resource Agencies no later than December 1 of each year;



• A wetland delineation shall be done to confirm that USACE and CDFW

jurisdictional wetlands have been successfully created/restored prior to

final approval of creation/restoration sites.

MM-BIO-2 Potential direct impacts to bird species covered under the MBTA will be mitigated

by restricting brushing and grading to outside of the breeding season of most bird

species (general breeding season is February 15 to August 31). Grubbing, grading,

or clearing during the breeding season of MBTA covered species could occur if it is

determined via a pre-construction survey that no nesting birds (or birds displaying

breeding or nesting behavior) are present immediately prior to grubbing, grading, or

clearing and will require approval of the City that no breeding or nesting avian

species are present in the vicinity of the grubbing, grading, or clearing. The City

shall be notified of any sensitive bird species identified during the pre-construction

surveys.

MM-BIO-3 To reduce edge effects, on-site human activity, and potential impacts related to the

introduction of exotic and domestic animals, the biological open space lots shall be

actively managed and monitored. The required habitat management plan (as

detailed in MM-BIO-1B) shall ensure that access be restricted to developed areas.

Permanent fencing shall be provided for all backyards abutting proposed project

open space. In addition, preserved habitat shall be posted with signs precluding

access due to habitat sensitivity and prohibiting dumping. Residents shall be

educated in access restrictions, control of domestic animals, prevention of irrigation

runoff, and sensitivity of habitats on site.

MM-BIO-4 If project grading (other than clearing and grubbing of sensitive habitats) is

necessary and adjacent to preserved on-site habitat during the bird breeding season

(February 15 to August 31), a qualified biologist shall conduct pre-construction

surveys in the adjacent habitat for the coastal California gnatcatcher\ and nesting

raptors. The survey shall begin not more than three days prior to the beginning of

grading activities. The Wildlife Agencies shall be notified if the gnatcatcher is

observed nesting within 300 feet of proposed grading or if raptors are observed

nesting within 500 feet of proposed grading activities. No activities which would

result in noise levels exceeding 60 dBA hourly Leq within this buffer shall be allowed.

If grading activities are not initiated prior to the breeding season, and any of these

species are present, and noise levels exceed this threshold, noise barriers shall be

erected to reduce noise impacts to occupied habitat to below 60 dBA hourly Leq

and/or the activities shall be suspended. Impacts resulting from noise for non-listed

species other than raptors are not considered significant, and mitigation is not

warranted.

Cultural Resources Mitigation Measures

MM-CR-1 An archeological monitor and a Luiseño Native American monitor shall be present

during the all earth moving and grading activities to assure that any potential

cultural resources, including tribal, found during project grading be protected.





activities in an effort to identify any unknown archaeological resources. Any newly

discovered cultural resource deposits shall be subject to cultural resources

evaluation, which shall include archaeological documentation, analysis and report

generation.

MM-CR-3 At least 30 days prior to beginning project construction, the Project Applicant shall

enter into a Cultural Resource Treatment and Monitoring Agreement (also known as

a pre-excavation agreement) with contact a Luiseño Tribe. the Rincon Tribe to notify

the Tribe of grading, excavation and the monitoring program and to develop a

Cultural Resources Treatment and Monitoring Agreement. The Agreement shall

address the treatment of known cultural resources, the designation, responsibilities,

and participation of professional Native American Tribal monitors during grading,

excavation and ground disturbing activities; project grading and development

scheduling; terms of compensation for the monitors; and treatment and final

disposition of any cultural resources, sacred sites, and human remains discovered

on site.

MM-CR-4 Prior to beginning project construction, the Project Archaeologist shall file a pre-

grading report with the City to document the proposed methodology for grading

activity observation, which will be determined in consultation with the contracted

Luiseño Tribe referenced in MM-CR-3. the Rincon Tribe. Said methodology shall

include the requirement for a qualified archaeological monitor to be present and to

have the authority to stop and redirect grading activities. In accordance with the

agreement required in MM-CR-3, the archaeological monitor’s authority to stop and

redirect grading will be exercised in consultation the Luiseño Native American

monitor with the Rincon Tribe in order to evaluate the significance of any

archaeological resources discovered on the property. Tribal and archaeological

monitors shall be allowed to monitor all grading, excavation, and groundbreaking

activities, and shall also have the authority to stop and redirect grading activities.

MM-CR-5 The landowner shall relinquish ownership of all cultural resources collected during

the grading monitoring program and from any previous archaeological studies or

excavations on the project site to the appropriate Tribe for proper treatment and

disposition per the Cultural Resources Treatment and Monitoring Agreement

referenced in MM-CR-3., including sacred items, burial goods, and all archaeological

artifacts that are found on the project area to the appropriate Tribe for proper

treatment and disposition. All cultural materials that are deemed by the Tribe to be

associated with burial and/or funerary goods will be repatriated to the Most Likely

Descendant as determined by the Native American Heritage Commission per

California Public Resources Code Section 5097.98.


conducted by an approved facility and the curation shalll be guided by California

State Historic Resource Commissions Guidelines for the Curation of Archaeological

Collections. The City of San Marcos shall provide the developer final curation



language and guidance on the project grading plans prior to issuance of the grading

permit, if applicable, during project construction.

collected during the grading monitoring program and from any previous

archaeological studies or excavations on the project site, with the exception of

sacred items, burial goods, and human remains which will be addressed in the

Treatment Agreement required in MM-CR-3, shall be tribally curated according to

the current professional repository standards by the Rincon Tribe. The collections

and associated records shall be transferred, including title, to the Rincon Tribe.





Coroner has made the necessary findings as to origin. Further, pursuant to California

Public Resources Code Section 5097.98(b) remains shall be left in place and free

from disturbance until a final decision as to the treatment and disposition has been

made. Suspected Native American remains shall be examined in the field and kept in

a secure location at the site If the San Diego County Coroner determines the

remains to be Native American, the Native American Heritage Commission (NAHC)

must be contacted within 24 hours. The NAHC must them immediately notify the

“most likely descendant(s)” of receiving notification of the discovery. The most likely

descendants(s) shall then make recommendations within 48 hours, and engage in

consultation concerning treatment of remains as provided in Public Resources Code

5097.98 and the Treatment Agreement described in MM-CR-3.,




assess the significance of such resources and shall meet and confer regarding the

mitigation for such resources. Pursuant to California Public Resources Code Section

21083.2(b) avoidance is the preferred method of preservation for archaeological

resources. If the Developer, the project archaeologist and the Tribe cannot agree on

the significance of mitigation for such resources, these issues will be presented to

the Planning Director for decision. The Planning Director shall make a determination

based upon the provisions of the California Environmental Quality Act with respect

to archaeological resources and shall take into account the religious beliefs,

customs, and practices of the Tribe. Notwithstanding any other rights available

under law, the decision of the Planning Director shall be appealable to the Planning

Commission and/or City Council.

Hazards/Hazardous Materials Mitigation Measures

MM-HAZ-1 Prior to grading activities, the project applicant shall prepare and implement a soils

management plan that addresses handling of soils containing naturally-occurring

arsenic during grading. The management plan shall be submitted to the City

Engineer for review and approval prior to the issuance of a grading permit.



MM-HAZ-2 Prior to issuance of building permits, a fire protection plan shall be prepared for the

project and submitted to the Planning Director and Fire Marshal for review and

approval. The fire protection plan shall include fire fuel clearing and fire fuel

management zones to provide a minimum 150-foot buffer between proposed

structures and natural habitat. The fire protection plan shall identify the responsible

parties for the ongoing fire fuel maintenance and the mechanism to ensure

compliance with fire clearing requirements. Implementation of the fire protection

plan shall be required prior project occupancy.

Noise Mitigation Measures

MM-N-1 Sound barriers ranging from five to ten feet shall be constructed to reduce future

onsite noise levels to be consistent with the Noise Element of the San Marcos

General Plan (60 dBA CNEL for single family and 65 dBA for multifamily). Locations

and heights of the proposed barriers are presented in Figure 7, Noise Mitigation

Measures. Barriers could include berms, wall, glass or a combination of these to

meet the required noise attenuation.

MM-N-2 A final noise assessment shall be prepared prior to the issuance of the first building

permit. This final report would identify the interior noise requirements based upon

architectural and building plans to meet the City’s established interior noise limit of

45 dBA CNEL.

MM-N-3 If outdoor usable areas are proposed in the non-residential mixed use areas of the

project, the design shall consider shielding form the buildings, increased setbacks

from the roadways or conduct a site specific noise study to determine compliance.

An interior noise assessment is required to mitigate the exterior noise levels to an

interior level of 50 dBA CNEL. This report should be conducted prior to the issuance

of building permits and would finalize the noise requirements based upon actual


MM-N-4 If rock crushing is proposed, upon starting of crushing operations, noise

measurements of the rock crushing facility shall be required to ensure compliance

with the City’s thresholds. If noise levels are found to be above the established

thresholds of 60 dBA at any existing single family residential use, 65 dBA for any

multifamily use or 70 dBA at a commercial use then additional mitigation in the

form of berms or temporary walls will need to be incorporated into the rock crusher

design to reduce the noise levels to below the City’s thresholds.

Traffic Mitigation Measures

MM-TR-1 The project applicant shall make a fair share contribution towards the following

improvements at the Twin Oaks Valley Road/SR-78 Eastbound Ramps:

• Construct an additional dedicated right-turn lane at eastbound (off-ramp)

approach of intersection.



• Restripe eastbound approach to include one left-turn lane, one shared left-

turn/through/right-turn lane, and two right-turn lanes.

MM-TR-2 The project applicant shall make a fair share contribution towards the widening of the

northbound approach of the Twin Oaks Valley Road/Discover Street-Barham Drive

intersection to construct a dedicated right-turn lane.



• Adjusting the ramp meter rate to accommodate the increase in demand at the

on-ramp; or

• Converting the existing HOV lane to a third SOV lane on the on-ramp to increase

on-ramp capacity.

A MITIGATED NEGATIVE DECLARATION will be prepared.

If adopted, the Mitigated Negative Declaration means that an Environmental Impact Report will not be

required. Reasons to support this finding are included in the attached Initial Study. The project file and

all related documents are available for review at the City of San Marcos, 1 Civic Center Drive, San

Marcos, CA 92069.

NOTICE

The public is invited to comment on the proposed Mitigated Negative Declaration during the review

period.

Date of Determination: March 19, 2014

Documents

FINAL Mitigated Negative Declaration/Initial Study Heart