Soil and Foundation Engineers REPORT OF LIMITED ......8265 COMMERCIAL STREET #12 LA MESA, CALIFORNIA 91941 Phone: (619) 462-9861 Fax: (619) 462-9859 July 31, 2015 TO: Fred Schmidt

REPORT OF LIMITED GEOTECHNICAL INVESTIGATIONThree Proposed Duplex Buildings

9924 San Juan StreetSpring Valley, CAA.P.N. 501 174 33

JOB NO. 15 6559

July 31, 2015

Prepared for:

Fred Schmidt9924 San Juan Street

Spring Valley, CA 91977

8265 COMMERCIAL STREET #12 La Mesa, CA 91942

Phone: 619-462-9861 Fax: 619 462-9859

Soil and Foundation Engineers

12/31/2015 12/31/2015

Soil and Foundation Engineers

8265 COMMERCIAL STREET #12 LA MESA, CALIFORNIA 91941Phone: (619) 462-9861 Fax: (619) 462-9859

July 31, 2015

TO: Fred Schmidt9924 San Juan StreetSpring Valley, CA 91977

SUBJECT:

In accordance with your request, and our proposal dated April 14, 2015 we haveperformed a geotechnical investigation for the proposed residential project. Weare presenting herein our findings and recommendations. In general, we foundthe lot to be suitable for the proposed project provided that therecommendations contained herein are adhered to. The building site is overlainwith up to 5 feet of loose slope wash and highly weathered bedrock materialsthat may require mitigation by remedial grading in some locations.

If you should have any questions after reviewing this report, please do nothesitate to contact our office. This opportunity to be of professional service issincerely appreciated.

Respectfully submitted,

C.W. La Monte Company Inc.

________________________________Clifford W. La Monte,R.C.E. 25241, G.E. 0495

____________________________________Jerry Redolfi, Project Geologist

REPORT OF LIMITED GEOTECHNICAL INVESTIGATIONThree Proposed Duplex Buildings, 9924 San Juan Street, SpringValley, CA, A.P.N. 501 174 33

Job No. 15 6559

TABLE OF CONTENTS

PROJECT DESCRIPTION ............................................................................................... 1SCOPE OF WORK ........................................................................................................... 2FINDINGS......................................................................................................................... 3Site Description ................................................................................................................ 3Description of Site Geology and Subsurface Soil Conditions ................................... 3Ground Water................................................................................................................... 5FAULTING AND SEISMICITY ..................................................................................... 5SEISMIC DESIGN PARAMETERS................................................................................ 6GEOLOGIC HAZARDS.................................................................................................. 7CONCLUSIONS............................................................................................................... 8RECOMMENDATIONS.................................................................................................. 9EARTH WORK AND GRADING.................................................................................. 9

Specifications and Preconstruction......................................................................... 9Fill Suitability ........................................................................................................... 10Site Preparation ....................................................................................................... 10Compaction and Method of Filling ...................................................................... 12Manufactured Slope Construction........................................................................ 12Temporary Cut Slopes............................................................................................ 12Excavation Characteristics ..................................................................................... 14Surface Drainage ..................................................................................................... 14Erosion Control........................................................................................................ 14

FOUNDATIONS AND CONCRETE SLAB-ON-GRADE RECOMMENDATIONS........................................................................................................................................... 14

Soil Bearing Value ................................................................................................... 15Lateral Load Resistance.......................................................................................... 16Post-Tensioned Foundation System ..................................................................... 16Anticipated Settlements ......................................................................................... 17Foundation Excavation Observation.................................................................... 17Foundation Plan Review ........................................................................................ 18

CONCRETE SLABS-ON-GRADE................................................................................ 18Exterior Concrete Slabs ................................................................................................. 18

Exterior Concrete Flatwork.................................................................................... 19DESIGN PARAMETERS FOR EARTH RETAINING STRUCTURES.................... 20

Soil Bearing Value ................................................................................................... 20Active Pressure for Retaining Walls..................................................................... 20Waterproofing and Drainage................................................................................. 22Backfill....................................................................................................................... 22

FIELD INVESTIGATION.............................................................................................. 23LABORATORY TESTS AND SOIL INFORMATION............................................... 23LIMITATIONS................................................................................................................ 24

______________________________________________________________________9924 San Juan St. July 31, 2015 Page 2Spring Valley, CA

TABLES

Table I Mapped Spectral Acceleration Values and Design Parameters Page 6

Table II Foundation Categories Page 16

Table III Post-tensioned Foundation Design Page 16

Table IV & V Equivalent Fluid Weights Page 21

Table VI Expansion Test Results Page 23

ATTACHMENTS

FIGURES

Figure No. 1A Site Location and Topographic Map

Figure No. 2B Plot Plan and Geotechnical Map

Figure No. 2 Site Plan – Proposed Development

Figure No. 3A-3F Test Excavation Logs

Figure No 4 Cross Section

Figure No. 5 Geologic Map Excerpt

Figure No. 6 Regional Fault Map

Figure No. 7 Landslide Hazard Map Excerpt

Figure No. 8 Retaining Wall Details

APPENDICIES

Appendix "A"- Standard Grading Specifications

Appendix "B" - Unified Soil Classification Chart

REPORT OF LIMITED GEOTECHNICAL INVESTIGATIONThree Proposed Duplex Buildings

9924 San Juan StreetSpring Valley, CAA.P.N. 501 174 33

PROJECT DESCRIPTION

The following report presents the results of a limited geotechnical investigationperformed for the proposed residential project. The project site is a developedresidential lot located at 9924 San Juan Street in the Casa de Oro area of San Diego County.Figure Number 1 (attached) provides a vicinity map showing the approximatelocation of the property and area topography. The site is improved with a one andtwo-story single family residence with an attached, partially below grade garage.

It is our understanding the existing improvements will be removed to make way forthree new duplex buildings that will be constructed on terraced levels. We anticipatethe proposed structures will be a maximum of three-stories with below gradeparking. Finish floor elevations of the parking level will range from approximately 8to 14 feet below the existing grade. Restrained masonry retaining walls, up to ninefeet in height, will be utilized in the garage construction. A ramped driveway willprovide access to the upper level buildings. A temporary cut slope will beconstructed behind the upper level buildings. The structure retaining walls will bebackfilled to the level of the second floor. After backfilling the structure retainingwalls an additional upper level wall will be terraced behind the structure at thesecond floor level. The upper level wall will retain the sloping hillside terrain (andreconstructed slope) above and may be masonry or geogrid reinforced, segmentalblock wall.

To aid in the preparation of this report, we were provided with a Topographic Survey,Schmidt Residence, 9924 San Juan Street, San Diego (Spring Valley), California by NaslandEngineering, dated December, 19, 2013; and an unreferenced, undated, grading planprovided by Gary Taylor & Associates. These plans were used in pour fieldmapping and to prepare our Plot Plan and Geotechnical Map (Figure 2A) and Site Plan(Figure No. 2B).

This report has been prepared for the exclusive use of the stated client and his designconsultants for specific application to the project described herein. Should theproject be changed in any way, the modified plans should be submitted to C. W. LaMonte Company, Inc. for review to determine their conformance with our


recommendations and to determine if any additional subsurface investigation,laboratory testing and/or recommendations are necessary. Our professional serviceshave been performed, our findings obtained and our recommendations prepared inaccordance with generally accepted engineering principles and practices. Thiswarranty is in lieu of all other warranties, expressed or implied.

SCOPE OF WORK

The scope of this investigation was limited to: surface reconnaissance, research ofreadily available geotechnical literature pertinent to the site, subsurface exploration,laboratory testing, engineering and geologic analysis of the field and laboratory dataand preparation of this report. More specifically, the intent of this investigation wasto:

Identify the subsurface conditions of the site to the depths influenced by theproposed construction.

Based on laboratory testing and our experience with similar sites in the area,identify the engineering properties of the various strata that may influence theproposed construction, including the allowable soil bearing pressures,expansive characteristics and settlement potential.

Describe possible geotechnical factors that could have an effect on the sitedevelopment.

Provide mapped spectral acceleration parameters relative to the 2013California Building Code.

Address potential construction difficulties that may be encountered due to soil

conditions and groundwater, and provide recommendations concerning theseproblems.

Recommend an appropriate foundation system for the proposed structure anddevelop soil engineering design criteria for the recommended foundationdesigns.

Present our opinions in this written report, which includes in addition to ourfindings and recommendations, a site plan showing the location of oursubsurface explorations, logs of the test trenches and a summary of ourlaboratory test results.


It was not within our scope of work to evaluate the site for hazardous materialscontamination. Further, we did not perform laboratory tests to evaluate the chemicalcharacteristics of the on-site soils in regard to their potentially corrosive impact to on-grade concrete and below grade improvements.

FINDINGS

Site Description

The project site is located on the north side of San Juan Street in the Casa de Oro area ofSan Diego County, California. The site is also bounded on the north with a singlefamily residence and on the east and west with apartments. The property isrectangular-shaped and is approximately 100 feet wide by 150 feet deep. A layout ofthe property is included on the Plot Plan and Geotechnical Map and Site Plan,Figures No. 2A. The site is improved with a one and two-story single familyresidence with a partially below grade, attached garage. Vegetation consists of lawngrass, a moderate growth of wild grasses and weeds, landscape shrubs and severaltrees.

Topographically, the site consists of hillside terrain sloping moderately to the south.Elevations in the vicinity of the site range from a high of about 234 feet (MSL) at thenorth end of the property to low of 201 feet (MSL) at the adjacent sidewalk level.Inclinations of the natural sloping terrain range from approximately 15 to 25 percent.

The existing single family residence is constructed on a minor cut and fill buildingpad. A cut slope approximately 5 feet in maximum height was placed in the areabehind the residence and is sloped at an approximate 1:1 (horizontal to vertical)inclination. A short fieldstone retaining wall is located along the toe of this slope.Minor fills rim the composite slope in the front of the lot. The base of the front slopeis retained with a masonry wall a maximum of 5 feet in height.

Description of Site Geology and Subsurface Soil Conditions

The site is underlain at depth with Tertiary-aged sedimentary deposits withassociated topsoils and subsoil and minor amounts of fill soils. These soil types aredescribed individually below in order of increasing age. Also refer the attached TestExcavation Logs, Figure No. 3A-3D. A Plot and Geotechnical Map is attached asFigure No. 2. An excerpt from a regional geologic map is included as Figure No. 4.


Undocumented Fills: A minor sliver fill was placed at the south end site tohelp level the existing structure’s building pad. The fills are locatedapproximately as shown on the attached geotechnical map, Figure No. 2. Thefills are composed of a mixture of the other units described in this section. It isassumed the fills are improperly placed and compacted and require remedialgrading .

Slope Wash: The “undisturbed” areas of the site are overlain with about 1.5 to2 feet of natural ground slope wash materials. The encountered surficialdeposits consist primarily of dark brown, dry, loose, silty sand and sandy silt.These topsoils are potential compressible and should be removed andreplaced as compacted fill in areas to receive settlement sensitiveimprovements or be penetrated with deepened foundation excavations. Muchof the slope wash in the existing building pad area was removed by priorgrading exposing the formational materials near the ground surface.

Residual Soil: A layer of subsoil clay was encountered in Test Boring No. 5,underlying the fill. The encountered residual clays were about one-half foot inn thickness and consist primarily of stiff, dark brown, sandy clay.

Mission Valley Formation (Tmv): The Preliminary Geologic Map of the El Cajon30' x 60' Quadrangle, Southern California (Todd, 2004) incorrectly indicates thatthe site is underlain with Cretaceous-aged Granitoid Rocks (Kgr), which werenot encountered in any of our explorations. The sedimentary formationencountered is characteristic of the Tertiary-aged, Mission Valley Formation,which is the assumed geologic unit for the purposes of this report.(Outcroppings of the Mission Valley Formation are mapped as close as a ½mile from the site). The Mission Valley Formation is described by the samepublication as: “a predominantly marine sandstone unit, rests conformably upon theStadium Conglomerate and is in turn conformably overlain by the PomeradoConglomerate. The Mission Valley Formation has a maximum thickness of 60 m andwas named for exposures in the La Jolla 7.5-minute quadrangle west of the quadrangle(Kennedy, 1975). Sandstone is soft and friable, light-olive-gray in color, fine- tomedium-grained, and composed mostly of quartz and K-feldspar with less than 2%plagioclase and biotite. Tongues of cobble conglomerate that is similar to the StadiumConglomerate comprise as much as 30% of the easternmost exposures of theformation. Interbeds and tongues of claystone of brackish water origin locally compose20% of the section.”

The upper surface of the formation encountered was highly weathered to adepth of approximately 4 to 5 feet below the existing grade. The weatheredmaterial consists primarily of light tan, loose to medium dense/firm clayey


sand and sandy clay with abundant caliche. The weathered material isunderlain with pinkish brown and light tan, slightly moist, hard, sandyclaystone with a little caliche interbedded with tan, very dense, clayeysandstone. The expansion potential of the formation varies from very low tohigh.

Ground Water

No groundwater was encountered in our test excavations at the time of ourinvestigation. However, it should be kept in mind, that any required gradingoperations might change surface drainage patterns and/or reduce permeability dueto the densification of compacted soils. Such changes of surface and subsurfacehydrologic conditions, plus irrigation of landscaping or significant increases inrainfall, may result in the appearance of surface or near-surface water at locationswhere none existed previously. The damage from such water is expected to be minorand cosmetic in nature only if good positive drainage is implemented at thecompletion of construction. Corrective action should be taken on a site-specific basisif, and when, it becomes necessary.

FAULTING AND SEISMICITY

No major faults are known to traverse the subject site but it should be noted that muchof Southern California, including the San Diego County area, is characterized by aseries of Quaternary-age fault zones, which typically consist of several individual, enechelon faults that generally strike in a south easterly – northwesterly direction. Someof these fault zones (and the individual faults within the zones) are classified as active.According to the criteria of the California Division of Mines and Geology, active faultzones are those, which have shown conclusive evidence of faulting during theHolocene Epoch (the most recent 11,000 years). An excerpt from the 2010 Fault ActivityMap of California, Geologic Data Map No. 6, is attached as Figure No. 6, showing therecency of faulting in the region.

A review of available geologic maps indicates that the Rose Canyon Fault Zone is thenearest active fault and is located about 11 miles west of the site. According to the2008 National Seismic Hazard Maps - Fault Parameters (USGS website), the MaximumMagnitude earthquake on the Rose Canyon Fault Zone is 6.9 (Ellsworth) or 6.7(Hanks) with a slip rate of 1.5. The Rose Canyon Fault Zone is currently classified asa Type "B" fault (California Probabilistic Seismic Hazard Maps, June 2003)


Other active fault zones in the region that could possibly affect the site include theCoronado Bank, San Diego Trough and San Clemente Fault Zones to the southwestand the Elsinore, Earthquake Valley, San Jacinto and San Andreas Fault Zones to thenortheast. However, the Rose Canyon Fault Zone is considered the most significantnearby fault with respect to the potential for seismically induced ground shaking(due to its closer proximity to the site).

The Alquist-Priolo Earthquake Fault Zoning Act was signed into California law onDecember 22, 1972 to mitigate the hazard of surface faulting to structures for humanoccupancy. According to Digital Images of Official Maps of Alquist-Priolo Earthquake FaultZones, of California, Southern Region (DMG CD 2000-003), by the California Departmentof Conservation, the site IS NOT located in or near an Alquist-Priolo Earthquake FaultZone.

SEISMIC DESIGN PARAMETERS

We have re-determined the mapped spectral acceleration values for the site utilizingU.S. Seismic Design Maps, Version 3.1.0 (July 11, 2013) from the USGS website. Theseismic design parameters are specific to the site and provide a solution for Section1613 of the 2012 IBC (which uses USGS hazard data available in 2008).The analysis included the following input parameters:

Design Code Reference Document: 2012 IBC

Site Soil Classification: Site Class C

Risk Category: I or II or III

Site Coordinates: 32.7491°N, 116.98234°W

The values generated by the Design Map Report are provided in the following table:

TABLE ISite Coefficients and Spectral Response Acceleration Parameters

Ss S1 Fa Fv Sms Sm1 Sds Sd1

0.857 0.332 1.057 1.468 0.906 0.488 0.604 0.325

Application to the criteria in Table I for seismic design does not constitute any kind


of guarantee or assurance that significant structural damage or ground failure willnot occur if ever seismic shaking occurs. The primary goal of seismic design is toprotect life, not to avoid all damage, since such design may be economicallyprohibitive.

GEOLOGIC HAZARDS

General: No geologic hazards of sufficient magnitude to preclude development ofthe site as currently proposed are known to exist. In our professional opinion and tothe best of our knowledge, the site is suitable for the proposed lateral additions.

Ground Shaking: A likely geologic hazard to affect the site is ground shakingresulting from movement along one of the major active fault zones mentioned above.Probable ground shaking levels at the site could range from slight to severe,depending on such factors as the magnitude of the seismic event and the distance tothe epicenter. It is likely that the site will experience the effects of at least onemoderate to large earthquake during the life of the proposed structure. Constructionin accordance with the minimum requirements of the current building codes andlocal governing agencies should minimize potential damage due to seismic activity.

Landslide Potential and Slope Stability: A review of the geologic hazards mapindicates there are no known deep or suspected ancient landslides located on the site.Due to the sites moderate topography and underlying competent materials, landslidehazards do not appear to present a significant risk to the proposed construction.However, we recommend global stability analysis be conducted on the finalizedconfiguration of the project.

As part of this investigation we reviewed the publication, “Landslide Hazards in theSouthern Part of the San Diego Metropolitan Area” by Tan and Giffen, 1995. Thisreference is a comprehensive study that classifies San Diego County into areas ofrelative landslide susceptibility. The subject site is located in an area classified as 3-1. The 3-1 is a general classification assigned to areas generally susceptible to slopemovement. Slopes within the 3-1 classification are considered at or near their stabilitylimits due to steep slopes and can be expected to fail locally when adverselymodified. Sites Within this classification are located outside the boundaries ofknown landslides but may contain observably unstable slopes that may be underlainby weak materials and/or adverse geologic structure. It should be noted that thatthis reference, typically classifies most hillside terrain, (that is not underlain bylandslides or landslide prone formations) within the 3 category. An excerpt from thisdocument is attached as Figure No. 7.


Liquefaction: The materials at the site are not subject to significant liquefaction dueto such factors as soil density, grain-size distribution, and groundwater conditions.

Soil Expansion: The foundation level materials at the site are considered to possessa medium to high expansion potential..

Flooding: The site is located outside the boundaries of both the 100-year and the500-year floodplains according to the maps prepared by the Federal EmergencyManagement Agency.

Tsunamis and Seiches: Tsunamis are great sea waves produced by submarineearthquakes or volcanic eruptions. Seiches are periodic oscillations in large bodies ofwater such as lakes, harbors, bays or reservoirs. Based on the project’s elevatedlocation, the site is considered to possess a very low risk potential from tsunamis orseiche activity.

CONCLUSIONS

In general, our findings indicate that the project site is suitable for the proposedaddition, provided the recommendations presented herein are followed. The mostsignificant geotechnical conditions that will influence site development aresummarized below.

Much of the site is capped by loose fill, slope wash and weathered formationalmaterials, which range from about 2 to over 5 feet in combined thickness.These loose surficial soils are considered unsuitable in their present conditionto support fill and/or settlement sensitive improvements. As such, all slopewash, fill and weathered formational materials not removed by planned sitegrading (plus and materials disturbed by future demolition operations) willneed to be removed from areas to support fills and/or settlement sensitiveimprovements and, where necessary to achieve planned site grades, shall beremoved and replaced as properly compacted fill. Refer to the Site Preparationheading in the following section of this report.

However, based on the proposed finish floor elevations and the encounteredsite conditions, it appears that the cut depths required for the basement levelparking will remove the loose topsoil and weathered formation from thebasement area, exposing competent, natural ground materials at below grade,finish floor elevations (Refer to the attached cross section, Figure No. 4).Therefore, no additional site preparation is required for locations exposingcompetent formational deposits at finish grade elevations.


Another significant geotechnical condition that will affect the construction ofthe improvements as proposed is the placement of temporary cut slopes andwhether there could be a need for temporary shoring during the constructionof the basement walls. Temporary excavations and shoring are discussed inthe following Temporary Cut Slopes section of this report.

Layers of claystone materials, encountered within the formational profile, areconsidered “moderately to highly expansive” as determined by ASTM D4829).Foundation recommendations reflect this probable finish grade condition.

To do away with expansive soil foundation recommendations it is feasible toperform remedial grading. This would involve mixing the clay soils withonsite and imported non-expansive soil to produce a non-detrimentallyexpansive mix. Refer to the Selective Grading section of this report for details.

The project, as presently designed, will include retaining walls terraced intothe hillside terrain. We recommend global stability analysis be conductedon the finalized configuration of the project.

We do not anticipate any significant cut-fill transitions below the proposedstructures.

No groundwater or seepage was observed at the time of our investigation ofour investigation. However, as is typical for “down hill” locations, temporaryseepage can develop during periods of prolonged heavy precipitation.Recommended drainage behind retaining walls should provide adequatemitigation.

RECOMMENDATIONS

EARTH WORK AND GRADING

Specifications and Preconstruction

All grading should conform to the guidelines presented in this report, Sections 1804,J107, J108, J109 and J110S of the 2013 California Building Code, the minimumrequirements of the County of San Diego, and the Standard Grading and ConstructionSpecifications, Appendix “A”, attached hereto, except where specifically supersededin the text of this report. Prior to grading, a representative of C. W. La Monte


Company Inc. should be present at the preconstruction meeting to provideadditional grading guidelines, if necessary, and to review the earthwork schedule.

Fill Suitability

On-site excavated materials may be used as compacted fill material or backfill. Theprimary on-site materials are anticipated to posses a low- to high-expansionpotential. However, the clay soils should not be used as retaining wall backfill. Anypotential import soil sites should be evaluated and approved by the GeotechnicalConsultant prior to importation. At least two working days notice of a potentialimport source should be given to the Geotechnical Consultant so that appropriatetesting can be accomplished. The type of material considered most desirable forimport is a non-detrimentally expansive granular material with some silt or claybinder.

Observation of Grading

Observation and testing by the soil engineer is essential during the gradingoperations. This allows the soil engineer to confirm the conditions anticipated by ourinvestigation, to allow adjustments in design criteria to reflect the actual fieldconditions exposed, and to determine that the grading proceeds in generalaccordance with the recommendations contained herein.

Site Preparation

Site preparation should begin with the removal of the all improvements designatedfor removal and vegetation and other deleterious materials from the portion of thelot that will be graded and/or that will receive improvements. This should includeall root balls from the trees removed and all significant root material. The resultingmaterials should be disposed of off-site.

Planned site grading for the proposed structures will consist primarily of a cuttingoperation to produce the parking levels. Excavations for the basement should exposecompetent materials at the finish surface. No additional site preparation should benecessary in the parking level areas where such favorable conditions areencountered.

However, any remaining, loose fill and slope wash materials (such as for thedriveway ramp) should be removed from areas of the site that will supportsettlement-sensitive improvements. As the project is presently planned, anyremaining soil removals are expected to range to maximum of 2 to 5 feet, but may bethicker in localized areas. The loose soil shall be removed to expose firm naturalground as determined by our field representative during grading. The removalsshould extend laterally a minimum of 5 feet beyond the structure perimeter or to a


distance equal to the depth of removals (whichever is greater). All removal areasshould be approved by a representative of our office prior to the placement ofadditional fill or improvements. In areas where lateral removals are limited, due toproperty line constraints, deepened foundations may be used to compensate for thiscondition.

Where existing grade is at a slope steeper than five units horizontal to one unitvertical (20-percent slope) and the depth of the fill exceeds 5 feet (1524 mm) benchingshall be provided in accordance with Figure J107.3 (reproduced below) of the 2010California Building Code (A copy is attached to the back of Appendix A). A keyshall be provided which is at least 10 feet (3048 mm) in width and 2 feet (610 mm) indepth. All removal areas should be approved by a representative of our office priorto the placement of fill or improvements.

Figure J107.3 from the 2010 California Building Code

Prior to placing any fill soils or constructing any new improvements in areas thathave been cleaned out to receive fill, the exposed soils should be scarified to a depthof approximately 6 to 12 inches, be moisture conditioned, and compacted to at least90 percent relative compaction.

2


Compaction and Method of Filling

All structural fill placed at the site should be compacted to a relative compaction of atleast 90 percent of its maximum dry density as determined by ASTM Laboratory TestD1557. Fills should be placed at or slightly above optimum moisture content, in liftssix to eight inches thick, with each lift compacted by mechanical means. Fills shouldconsist of approved earth material, free of trash or debris, roots, vegetation, or othermaterials determined to be unsuitable by our soil technicians or project geologist. Allmaterial should be free of rocks or lumps of soil in excess of twelve inches inmaximum width. However, in the upper two feet of pad grade, no rocks or lumps ofsoil in excess of six inches should be allowed.

Utility trench backfill within five feet of the proposed structures and beneath allpavements and concrete flatwork should be compacted to a minimum of 90 percentof its maximum dry density. The upper one-foot of pavement subgrade and basematerial should be compacted to at least 95 percent relative density. All grading andfill placement should be performed in accordance with the local Grading Ordinance,the California Building Code, and the Recommended Grading Specifications andSpecial Provisions attached hereto as Appendix A.

Manufactured Slope Construction

Proposed cut and fill slopes that may be placed should be constructed at aninclination of 2:1 or flatter (horizontal to vertical). Compaction of slopes should beperformed by back-rolling with a sheepsfoot compactor at vertical intervals of fourfeet or less as the fill is being placed, and track-walking the face of the slope when theslope is completed. As an alternative, the fill slopes may be overfilled by at leastthree feet and then cut back to the compacted core at the design line and grade.

Temporary Cut Slopes

Temporary cut slopes, up to 17 feet in maximum height, are planned for theproposed basement excavation. We anticipate temporary slopes may be excavated ata minimum inclination of 1.0:1.0 (horizontal to vertical) in competent formationaldeposits. In addition, a short vertical cut will be allowable at the base toaccommodate the foundation excavation.

The stability of temporary slopes should be verified by the geotechnical consultant atthe time of excavation. No surcharge loads such as stockpiles, vehicles, etc. should beallowed within a distance from the top of temporary slopes equal to half the slopeheight. Further care should be taken not to undermine adjacent improvements bythe placement of temporary excavations.


It appears there is sufficient area to place the 1:1 recommended cut slope. However,in the event it is not feasible to place temporary cut slopes sloped at therecommended inclinations temporary or permanent shoring will be required in suchareas. If such is the case, excavation shoring should be provided in such locationswhere undermining or other damage to adjacent structures and improvements is anissue. Design for shoring is, typically, provided by the installation contractor.Supplemental soil design parameters can be provided on request. Plans for shoringshould be reviewed by the geotechnical consultant.

It should be noted that the contractor is solely responsible for designing andconstructing stable, temporary excavations and may need to shore, slope, or benchthe sides of trench excavations as required to maintain the stability of the excavationsides where friable sands or loose soils are exposed. The contractor’s “responsibleperson”, as defined in the OSHA Construction Standards for Excavations, 29 CFR,Part 1926, should evaluate the soil exposed in the excavations as part of thecontractor’s safety process. In no case should slope height, slope inclination, orexcavation depth, including utility trench excavation depth, exceed those specified inlocal, state, and federal safety regulations. Actual safe slope angles should beverified by the geotechnical consultant at the time of excavation.

Select Grading

Much of the existing on-site soils were found to possess a “medium” to “high”expansive potential. In order to use conventional spread foundations and on-gradefloor slabs, the expansive on-site soils that are to be used as fill material should bemixed with other select fills to produce a nondetrimentally expansive mixture of soil,or should be placed at least four (4) feet below finish pad grade. The select fill materialshould consist of a granular soil with an Expansion Index of less than 50. The selectfill may be mined from existing, nondetrimentally expansive on-site soils, or may beimported from other sites. The select soil should be approved by our engineeringstaff prior to importing.

In addition, wherever detrimentally expansive soil is determined to occur naturallywithin four (4) feet of finish pad grade, it should be removed and replaced withnondetrimentally expansive material. The bottom of the over-excavated areas shouldbe sloped in such a manner that water does not become trapped in the over-excavatedzone. Where the mixture of soil does not produce a nondetrimentally expansive fillmaterial or detrimentally expansive soil is not removed, special consideration forheaving soil will need to be incorporated into the foundation design.


Excavation Characteristics

Based on our exploratory excavations, the subsurface materials at the site appearmoderately difficult to excavate with conventional earthmoving equipment and willgenerate clayey sand and expansive, sandy clay materials.

Surface Drainage

Surface runoff into graded areas should be minimized. Where possible, drainageshould be directed to suitable disposal areas via non-erodible devices such as pavedswales, gunited brow ditches, and storm drains. Pad drainage should be designed tocollect and direct surface water away from proposed structures and the top of slopesand toward approved drainage areas. For earth areas, a minimum gradient of onepercent should be maintained.

The ground around the proposed buildings should be graded so that surface waterflows rapidly away from the buildings without ponding. In general, we recommendthat the ground adjacent to buildings slope away at a gradient of at least two-percent. Densely vegetated areas where runoff can be impaired should have aminimum gradient of five percent within the first five feet from the structure.

Erosion Control

In addition, appropriate erosion-control measures shall be taken at all times duringconstruction to prevent surface runoff waters from entering footing excavations,ponding on finished building pad or pavement areas, or running uncontrolled overthe tops of newly-constructed cut or fill slopes. Appropriate Best ManagementPractice (BMP) erosion control devices should be provided in accordance with localand federal governing agencies.

FOUNDATIONS AND CONCRETE SLAB-ON-GRADE RECOMMENDATIONS

The expansive characteristics of the materials underlying the site are variable. Forthis reason we cannot provide site specific recommendations until finish pads areexposed and foundation conditions can be better evaluated. The followingfoundation recommendations are for one- to three-story residential structures andare separated into categories dependent on the thickness and geometry of theunderlying fill soils as well as the Expansion Index of the prevailing subgrade soils ofa particular building pad. The recommended minimum foundation and interiorconcrete slab design criteria for each category is presented on Table II, Categorycriteria is listed below. It appears expansive soil criteria mainly apply to project siteas anticipated fill thicknesses will be less than 10 feet. We will evaluate the Finalfoundation categories once site grading has been completed.


CATEGORY CRITERIA

Category I: Maximum fill thickness is less than 20 feet and Expansion Index is lessthan or equal to 50.

Category II: Maximum fill thickness is less than 50 feet and Expansion Index is lessthan or equal to 90, or variation in fill thickness is between 10 feet and20 feet.

Category III: Fill thickness exceeds 50 feet, variation in fill thickness exceeds 20 feet,or Expansion Index exceeds 90 but is less than 130.

TABLE IIFOUNDATION RECOMMENDATIONS BY CATEGORY

Category

I 12”Two No. 4 barsone top and one bottom

No. 3 bars at 24 incheson center, both directions

4”

II 18”Four No. 4 barstwo top and two bottom


4”

III 24”Four No. 5 barstwo top and two bottom


5”

The embedment depths presented in the above table should be measured from thelowest adjacent pad grade for both interior and exterior footings. The conventionalfoundations should have a minimum width of 12 inches and 24 inches for continuousand isolated footings, respectively. Specific recommendations for slab-on-gradefloors are provided in the following report section.

Soil Bearing Value

The recommended allowable bearing capacity for foundations with minimumdimensions described herein is 3,500 psf for footings when bearing in competentnatural ground formation and 2000 psf when placed in properly compacted fill. Thevalues presented herein are for dead plus live loads and may be increased by one-third when considering transient loads due to wind or seismic forces.

MinimumFootingDepth

ContinuousFooting

Reinforcement

InteriorSlab

Reinforcement

MinimumSlab

Thickness


Lateral Load Resistance

Lateral loads against foundations may be resisted by friction between the bottom ofthe footing and the supporting soil, and by the passive pressure against the footing.The coefficient of friction between concrete and soil may be considered to be 0.3. Thepassive resistance may be considered to be equal to an equivalent fluid weight of 350pounds per cubic foot in recompacted fill or firm natural ground material. Thisassumes the footings are poured tight against undisturbed soil. If a combination ofthe passive pressure and friction is used, the friction value should be reduced by one-third.

Post-Tensioned Foundation System

Post-tensioned concrete slab and foundation systems should be considered for thesupport of the proposed structures on building pads with a medium to highexpansion potential. The post-tensioned systems should be designed by a structuralengineer experienced in post-tensioned slab design and design criteria of the Post-Tensioning Institute (PTI) as required by the 2013 California Building Code. The post-

tensioned design should incorporate the geotechnical parameters presented on Table II for theparticular Foundation Category designated. The foundations for the post-tensioned slabs shouldbe embedded in accordance with the recommendations of the structural engineer

The post-tensioned design should incorporate the geotechnical parameters presentedon Table III.

TABLE IIIPOST-TENSIONED FOUNDATIONSYSTEM DESIGN PARAMETERS

Foundation CategoryPost-Tensioning Institute (PTI)Third Edition Design Parameters I II III

Thomthwaite Index -20 -20 -20

Equilibrium Suction 3.9 3.9 3.9

Edge Lift Moisture Variation Distance, em (feet) 5.3 5.1 4.9

Edge Lift, Ym (inches) 0.61 1.10 1.58

Center Lift Moisture Variation Distance, em

(feet)9.0 9.0 9.0

Center Lift, Υm (inches) 0.30 0.47 0.66

If the structural engineer proposes a post-tensioned foundation design method otherthan the 2013 CBC:


The criteria presented in Table III are still applicable.

Interior stiffener beams should be used for Foundation Categories II and III.

The width of the perimeter foundations should be at least 12 inches.

The perimeter footing embedment depths should be at least 12 inches, 18inches and 24 inches for foundation categories I, II, and Ill, respectively. Theembedment depths should be measured from the lowest adjacent pad

Anticipated Settlements

Based on our experience with the soil types on the subject site, the soils shouldexperience settlement in the magnitude of less than 0.5 inch under proposedstructural loads.

It should be recognized that minor hairline cracks normally occur in concrete slabsand foundations due to shrinkage during curing and/or redistribution of stressesand some cracks may be anticipated. Such cracks are not necessarily an indication ofexcessive vertical movements.

Foundation Excavation Observation

All foundation excavations should be observed by the Geotechnical Consultant priorto placing reinforcing steel and formwork in order to verify compliance with thefoundation recommendations presented herein. All footing excavations should beexcavated neat, level and square. All loose or unsuitable material should be removedprior to the placement of concrete.

Pre-saturation

If expansive clay subgrade conditions are present at the completion of grading, thebottom of foundation excavations and slab subgrade requires pre-saturation prior tothe placement of concrete. The subgrade encountered in our explorations wasgenerally very moist to wet. However, subgrade moisture conditions can varyseasonal. Therefore, moisture conditioning may be necessary prior to placement offoundations and floor slabs. The most important practice in reducing the potentialfor lifting of concrete slabs due to expansive soil is the pre-saturation of the soil priorto pouring concrete. A common specification is to attain a 110% to 120% of optimummoisture content to a depth of at least 18". This moisture penetration should beverified by the soil engineer prior to the placement of concrete.


Water migrates very slowly through most expansive soil; therefore, obtaining therecommended pre-saturation can be a tedious process. Experienced contractors oftenspread an ample amount of a surfactant such as laundry detergent on the groundduring pre-saturation to aid in obtaining the recommended moisture penetration.Another technique is to utilize a hand auger to create a grid of small diameter holes(about 2 inches in diameter); 2 feet deep. The holes can be filled with crushed rocksuch as pea gravel. These holes fill with water during pre-saturation to further aid inobtaining the recommended moisture penetration.

Foundation Plan Review

The finalized, foundation plans should be submitted to this office for review toascertain that the recommendations provided in this report have been followed andthat the assumptions utilized in its preparation are still valid. Additional oramended recommendations may be issued based on this review.

CONCRETE SLABS-ON-GRADE

It is our understanding that the floor system of the proposed structure may consist ofconcrete slab-on-grade floors. The following recommendations assume that thesubgrade soils have been prepared in accordance with the recommendationspresented in the “Grading and Earthwork” section of this report and the subgrade wasadequately prostrated as discussed in the Foundations section of this report. Inaddition, the following recommendations are considered the minimum slabrequirements based on the soil conditions and are not intended in lieu of structuralconsiderations. Proper design by a post tensioned foundation system professionalmay supersede these recommendations.

Interior Floor Slabs

We recommend a minimum floor slab thickness of four (4) inches (actual) isrecommended for slab-on-grade floors (Also refer to Table II for additional thicknessrecommendations). The floor slabs should be reinforced in accordance with Table II.Slab reinforcing should be supported by chairs and be positioned at mid-height inthe floor slab. Slab reinforcement shall be integrated into the foundation.

Exterior Concrete Slabs

On-grade exterior concrete slabs for walks and patios should have a thickness of fiveinches and should be reinforced with at least No. 3 reinforcing bars placed at 18inches on center each way. Exterior slab reinforcement should be placedapproximately at mid-height of the slab. Reinforcement and control joints should be


constructed in exterior concrete flatwork to reduce the potential for cracking andmovement. Joints should be placed in exterior concrete flatwork to help control thelocation of shrinkage cracks. Spacing of control joints should be in accordance withthe American Concrete Institute specifications. When slabs abut foundations theyshould be doweled into the footings.

The slab subgrade should be prepared as recommendation in the Site Preparationsection of this report. Exterior slab subgrade in any exposes expansive soils requirespre-saturation as discussed in the foundations section of this report. We recommenddriveway slabs with clay subgrade be underlain with at least 6 inches of aggregatebase.

Vehicular traffic should be avoided until the slab concrete is adequately cured.

Exterior Concrete Flatwork

On-grade exterior concrete slabs for walks and patios should have a thickness of fourinches and should be reinforced with at least No. 3 reinforcing bars placed at 24inches on center each way. Exterior slab reinforcement should be placedapproximately at mid-height of the slab. Reinforcement and control joints should beconstructed in exterior concrete flatwork to reduce the potential for cracking andmovement. Joints should be placed in exterior concrete flatwork to help control thelocation of shrinkage cracks. Spacing of control joints should be in accordance withthe American Concrete Institute specifications. When slabs abut foundations theyshould be doweled into the footings.

Concrete Driveway Slabs

Driveway slabs may be placed directly on properly compacted non-expansivesubgrade. The minimum thickness of the slab should be at least 5 inches or per theminimum requirements of the County of San Diego. The slabs should be reinforcedwith at least No. 3 bars placed at 24 inches on center each way. Slab reinforcingshould be supported by chairs and be positioned at mid-height in the floor slab.

Spacing of control joints should be in accordance with the American ConcreteInstitute specifications and/or the requirements by San Diego County. A deepenededge is recommended for slab sections, which will minimize the potential for lateralcreep or wheel damage.


DESIGN PARAMETERS FOR EARTH RETAINING STRUCTURES

The below foundation values are provided for conventional shallow foundations.

Passive Pressure: The passive pressure for the prevailing soil conditions may beconsidered to be 300 pounds per square foot per foot of depth. This pressure maybe increased one-third for seismic loading. The coefficient of friction for concrete tosoil may be assumed to be 0.25 for the resistance to lateral movement. Whencombining frictional and passive resistance, the friction value should be reduced byone-third.

Soil Bearing Value

Conventional spread footings with the above minimum dimensions may be designedfor an allowable soil bearing pressure of 2,000 pounds per square foot for foundationbearing in compacted fill. Foundations bearing in “bedrock” may utilize 3000 psf.

Active Pressure for Retaining Walls

Lateral pressures acting against masonry and cast-in-place concrete retaining wallscan be calculated using soil equivalent fluid weight. The equivalent fluid weightvalue used for design depends on allowable wall movement. Walls that are free torotate at least 0.5 percent of the wall height can be designed for the active equivalentfluid weight. Retaining walls that are restrained at the top (such as basement walls),or are sensitive to movement and tilting should be designed for the at-rest equivalentfluid weight.

Values given in the table below are in terms of equivalent fluid weight and assume atriangular distribution. The provided equivalent fluid weight values assume thatonsite or imported, sandy soils (SP, SM, SC) with an Expansion Index (E.I.) of lessthan 50 will be used as backfill. No highly expansive clay soils (CH) should be usedas retaining wall backfill.


Pressures for Seismic Ground Motions: Using a Kh value of 0.12 the modifiedequivalent fluid pressure (EFP) due to earthquake ground motion is 14 pcf. This isan inverted triangular distribution. The point of application of the resultant force ofthe seismic EFP is located at approximately 0.6H (H=Height of the retaining wall)above the base of the wall. The above seismic force should be used in addition to the“static” or at-rest earth pressure.

Surcharge Loads: Retaining walls must be designed to resist horizontal pressuresthat may be generated by surcharge loads applied at or near the ground surface.Where an imaginary 1:1 plane projecting downward from the outermost edge of a

Surface slope of Cantilever equivalent Restrained equivalent

Retained material Fluid weight Fluid weight

Horizontal to vertical* (active pressure) (at-rest pressure)

(pcf) (pcf)

LEVEL 45 605 t o l 49 64

4 t o l 53 68

3 t o l 57 72

2 t o l 61 76

Surface slope of Cantilever equivalent Restrained equivalent

Retained material Fluid weight Fluid weight

Horizontal to vertical* (active pressure) (at-rest pressure)

(pcf) (pcf)

LEVEL 30 605 t o l 32 64

4 t o l 35 68

3 t o l 38 72

2 t o l 43 76

TABLE NO. IVTABLE OF EQUIVALENT FLUID WEIGHTS FOR ACTIVE PRESSUREAND AT-REST PRESSURE BASED ONSITE BACKFILL CONDITON

TABLE NO. VTABLE OF EQUIVALENT FLUID WEIGHTS FOR ACTIVE PRESSURE ANDAT-REST PRESSURE BASED IMPORTED SELECTBACKFILL CONDITON


surcharge load or foundation intersects the retaining wall, that portion of the wallbelow the intersection should be designed for an additional horizontal thrust from auniform pressure equivalent to one-third the maximum anticipated surcharge load.

Vehicular Loads: In the case of vehicular loads coming closer than one-half theheight of the wall, we recommend a live load surcharge pressure equal to not lessthan 2 feet of soil surcharge with an average unit weight of 125 pcf.

Waterproofing and Drainage

In general, retaining walls should be provided with a drainage system adequate toprevent the buildup of hydrostatic forces and waterproofed as specified by theproject architect. Also refer to American Concrete Institute ACI 515.R (A Guide tothe Use of Waterproofing, Damp Proofing, Protective and Decorative BarriersSystems for Concrete).

Positive drainage for retaining walls should consist of a vertical layer of permeablematerial positioned between the retaining wall and the soil backfill. Such permeablematerial may be composed of a composite drainage geosynthetic or a naturalpermeable material such as crushed rock or clean sand at least 12 inches thick andcapped with at least 12 inches of backfill soil. The gravel should be wrapped in ageosynthetic filter fabric. Provisions should be made for the discharge of anyaccumulated groundwater. The selected drainage system should be provided with aperforated collection and discharge pipe placed along the bottom of the permeablematerial near the base of the wall. The drain pipe should discharge to a suitabledrainage facility. A typical retaining wall detail is attached as Figure No. 8A. Iflateral space (due to property line constraints) is insufficient to allow installation ofthe gravel-wrapped "burrito" drain, a geocomposite system may be used in lieu ofthe typical gravel and pipe subdrain system. TenCate's MiraDrain (and similarproducts) provide a "low-profile" drainage system that requires minimal lateralclearance for installation. See Figure No. 8B for a typical MiraDrain detail, which isprovided by the manufacturer. MiraDRAIN and similar products may also beincorporated into a waterproofing system and provide a slab drainage system (Pleasenote that supplemental manufacturer’s details will be required to provide awaterproofed system).

Backfill

All backfill soils should be compacted to at least 90% relative compaction. The typicalon-site clay (CH) materials are not suitable for retaining wall backfill. Soil with anexpansion index (EI) of greater than 50 should not be used as backfill material behindretaining walls. The wall should not be backfilled until the masonry has reached anadequate strength.


FIELD INVESTIGATION

Six test explorations were placed on the lot, using a hand auger sampling system.The excavations were placed specifically in areas where representative soilconditions were expected and/or where the proposed structures will be located. Ourinvestigation also included a visual site reconnaissance. The excavations werevisually inspected and logged by our field geologist, and samples were taken of thepredominant soils throughout the field operation. Test excavation logs have beenprepared on the basis of our inspection and the results have been summarized onFigures No. 3 A through 3D. The predominant soils have been classified inconformance with the Unified Soil Classification System (refer to Appendix B). Inaddition, a verbal textural description, the wet color, the apparent moisture and thedensity or consistency are provided. The density of granular soils is given as veryloose, loose, medium dense, dense or very dense. The density of cohesive soils is

given as either very soft, soft, medium stiff, stiff, very stiff, and hard. Disturbed andrelatively undisturbed samples of typical and representative soils were obtainedfrom the test excavations and transported to the laboratory for testing.

LABORATORY TESTS AND SOIL INFORMATION

Laboratory tests were performed in accordance with the generally acceptedAmerican Society for Testing and Materials (ASTM) test methods or suggestedprocedures. A brief description of the tests and evaluations performed is presentedbelow:

CLASSIFICATION: Field classifications were verified in the laboratory by visualexamination. The final soil classifications are in accordance with the Unified SoilClassification System.

MOISTURE-DENSITY: In-place moisture contents and dry densities weredetermined for representative soil samples. This information was an aid toclassification and permitted recognition of variations in material consistency withdepth. The dry unit weight is determined in pounds per cubic foot, and the in-placemoisture content is determined as a percentage of the soil's dry weight. The resultsare summarized in the test excavation logs.

EXPANSION INDEX: Expansion Index testing on a remolded sample wasperformed on a representative sample of the existing clayey subsoil. The test wasperformed on the portion of the sample passing the #4 standard sieve. The samplewas brought to near optimum moisture content. The specimen was then compactedin a 4-inch-diameter mold in two equal layers by means of a tamper, then trimmed to


a final height of 1 inch, and brought to a saturation of approximately 50 percent. Thespecimen was placed in a consolidometer with porous stones at the top and bottom;a total normal load of 12.63 pounds was placed (144.7 psf). The sample wassaturated, and the change in vertical movement was recorded until the rate ofexpansion became nominal. The expansion index is reported below as the totalvertical displacement.

TABLE VIEXPANSION INDEX TEST

Sample Location: B-1, 3’ to 6' B-4, 2’ to 4'

Initial Moisture Content: 12.9% 12.0%

Initial Dry Density: 107.0 110.0

Final Moisture Content: 25 % 23 %

Expansion Index: 91 21

CBC Classification: Medium to high Low

LIMITATIONS

The recommendations presented in this report are contingent upon our review offinal plans and specifications. Such plans and specifications should be madeavailable to the Geotechnical Engineer and Engineering Geologist so that they mayreview and verify their compliance with this report and with Appendix Chapter 33 ofthe Uniform Building Code.

It is recommended that C.W. La Monte Company Inc. be retained to providecontinuous soil engineering services during the earthwork operations. This is toverify compliance with the design concepts, specifications or recommendations andto allow design changes in the event that subsurface conditions differ from those

anticipated prior to start of construction.

The recommendations and opinions expressed in this report reflect our best estimateof the project requirements based on an evaluation of the subsurface soil conditionsencountered at the subsurface exploration locations and on the assumption that thesoil conditions do not deviate appreciably from those encountered. It should berecognized that the performance of the foundations and/or cut and fill slopes may beinfluenced by undisclosed or unforeseen variations in the soil conditions that mayoccur in the intermediate and unexplored areas. Any unusual conditions notcovered in this report that may be encountered during site development should bebrought to the attention of the Geotechnical Engineer so that he may makemodifications if necessary.


This office should be advised of any changes in the project scope or proposed sitegrading so that we may determine if the recommendations contained herein areappropriate. It should be verified in writing if the recommendations are found to beappropriate for the proposed changes or our recommendations should be modifiedby a written addendum.

The findings of this report are valid as of this date. Changes in the condition of aproperty can, however, occur with the passage of time, whether they are due tonatural processes or the work of man on this or adjacent properties. In addition,changes in the Standards-of-Practice and/or Government Codes may occur. Due tosuch changes, the findings of this report may be invalidated wholly or in part bychanges beyond our control. Therefore, this report should not be relied upon after aperiod of two years without a review by us verifying the suitability of theconclusions and recommendations.

In the performance of our professional services, we comply with that level of careand skill ordinarily exercised by members of our profession currently practicingunder similar conditions and in the same locality. The client recognizes thatsubsurface conditions may vary from those encountered at the locations where ourborings, surveys, and explorations are made, and that our data, interpretations, andrecommendations are based solely on the information obtained by us. We will beresponsible for those data, interpretations, and recommendations, but shall not beresponsible for the interpretations by others of the information developed. Ourservices consist of professional consultation and observation only, and no warrantyof any kind whatsoever, express or implied, is made or intended in connection withthe work performed or to be performed by us, or by our proposal for consulting orother services, or by our furnishing of oral or written reports or findings.

It is the responsibility of the stated client or their representatives to ensure that theinformation and recommendations contained herein are brought to the attention ofthe structural engineer and architect for the project and incorporated into theproject's plans and specifications. It is further their responsibility to take thenecessary measures to insure that the contractor and his subcontractors carry outsuch recommendations during construction. The firm of C.W. La Monte Co. Inc. shallnot be held responsible for changes to the physical condition of the property, such asaddition of fill soils or changing drainage patterns, which occur subsequent to theissuance of this report.

We do not direct the Contractor's operations, and we cannot be responsible for thesafety of Personnel other than our own on the site; the safety of other is theresponsibility of the Contractor. The Contractor should notify the Owner if heconsiders any of the recommended actions presented herein to be unsafe.

SITE LOCATION AND TOPOGRAPHIC MAP

Figure No. 1

C.W. La Monte Company Inc.Soil and Foundation Engineers

Excerpt from USGS Topographic Maps El Cajon and Jamul Mt. Quadrangles,7.5-Minute Series, 2012

B-1

B-2

B-3

B-4

B-6

Tmv

B-5

A'

A

Tmv

Tmv

SAN JUAN STREET0 20 40

FEET

FIGURE NO. 2 A

3-Unit Residential Project9924 San Juan St., Spring Valley, CA

Approximate TestBoring Location

LEGEND

Cross Section

A A

Geologic Units

Tmv =( Mission Valley Fm.)

B-1

0 20 40

FEET

B-1

B-2

B-3

B-4

B-6

Tmv

B-5

Tmv

Tmv

SAN JUAN STREET

FIGURE NO. 2 B


Approximate TestBoring Location

LEGEND

Cross Section

A A

Geologic Units

Tmv =( Mission Valley Fm.)

B-1

TEST BORING NO.

JBR

Hand Auger

05/29/2015

DE

PT

H(f

ee

t)

SA

MP

LE

SB

UL

K

UN

DIS

TU

RB

ED

BL

OW

S/

FO

OT

MO

IST

UR

E(%

)

DR

YD

EN

SIT

Y(P

CF

)

FIGURE NO. 3

CL

AS

SIF

ICA

TIO

N

U.S

.C.S

DESCRIPTION OF SUBSURFACE CONDITIONS

Surface Elevation: Date: Logged By:

Excavation Method:

2

3

4

5

6

7

8

9

10

11

12


A

Exavation Bottom

B-1

Light tan, slightly moist medium dense,clayey sand with abundant caliche

SLOPE WASH

Dark brown, slightly moist, soft to firm,sandy, clayey silt with small caliche fragments

MISSION VALLEY FORMATION (Tmv)

Pinkish brown, slightly moist, hardsandy claystone/sandy siltstone with a little caliche

Tan, moist, dense to very densedsandy very clayey sand

Pinkish brown, slightly moist, hardsandy clay with a little caliche

ML

CLML

CLCH

SC

SC

231'

TEST BORING NO.

JBR

Hand Auger

05/29/2015

DE

PT

H(f

ee

t)

SA

MP

LE

SB

UL

K

UN

DIS

TU

RB

ED

BL

OW

S/

FO

OT

MO

IST

UR

E(%

)

DR

YD

EN

SIT

Y(P

CF

)

FIGURE NO. 3

CL

AS

SIF

ICA

TIO

N

U.S

.C.S



Excavation Method:

2

3

4

5

6

7

8

9

10

11

12


B

Exavation Bottom

B-2

Light tan, slightly moist, loose to medium dense/firmclayey sand and sandy clay with abundant calicheHighly weathered

SLOPE WASH



Pinkish brown and light tan, slightly moist, hardsandy claystone/sandy siltstone with a little caliche

ML

CLML

SCCL

228'

@ 6.5 feet drilling refusal with hand auger

TEST BORING NO.

JBR

Hand Auger

05/29/2015

DE

PT

H(f

ee

t)

SA

MP

LE

SB

UL

K

UN

DIS

TU

RB

ED

BL

OW

S/

FO

OT

MO

IST

UR

E(%

)

DR

YD

EN

SIT

Y(P

CF

)

FIGURE NO. 3

CL

AS

SIF

ICA

TIO

N

U.S

.C.S



Excavation Method:

2

3

4

5

6

7

8

9

10

11

12


C

Exavation Bottom

B-3


SLOPE WASH



Pinkish brown with light tan, slightly moist, hardsandy claystone/sandy siltstone with a little caliche

ML

CLML

SCCL

222'

@ 6.0 feet drilling refusal with hand auger

TEST BORING NO.

JBR

Hand Auger

05/29/2015

DE

PT

H(f

ee

t)

SA

MP

LE

SB

UL

K

UN

DIS

TU

RB

ED

BL

OW

S/

FO

OT

MO

IST

UR

E(%

)

DR

YD

EN

SIT

Y(P

CF

)

FIGURE NO. 3

CL

AS

SIF

ICA

TIO

N

U.S

.C.S



Excavation Method:

2

3

4

5

6

7

8

9

10

11

12


D

Exavation Bottom

B-4



Pinkish brown and reddish brown, slightly moist, hardsandy claystone/sandy siltstone

CLCH

SCCL

213'

9.8 110

TEST BORING NO.

JBR

Hand Auger

05/29/2015

DE

PT

H(f

ee

t)

SA

MP

LE

SB

UL

K

UN

DIS

TU

RB

ED

BL

OW

S/

FO

OT

MO

IST

UR

E(%

)

DR

YD

EN

SIT

Y(P

CF

)

FIGURE NO. 3

CL

AS

SIF

ICA

TIO

N

U.S

.C.S



Excavation Method:

2

3

4

5

6

7

8

9

10

11

12


E

Exavation Bottom

B-5

RESIDUAL SOIL

FILL

dark brown, moist, stiff, sandy clay

Light tan and pinkish brown, slightly moist, loose to mediumdense/firm clayey sand and sandy clay with some caliche


Pinkish brown, slightly moist, hardsandy claystone/sandy siltstone with a little caliche

Tan, moist, dense to very densedsandy very clayey sand

ML

CLML

SC

211.5'

CH

TEST BORING NO.

JBR

Hand Auger

05/29/2015

DE

PT

H(f

ee

t)

SA

MP

LE

SB

UL

K

UN

DIS

TU

RB

ED

BL

OW

S/

FO

OT

MO

IST

UR

E(%

)

DR

YD

EN

SIT

Y(P

CF

)

FIGURE NO. 3

CL

AS

SIF

ICA

TIO

N

U.S

.C.S



Excavation Method:

2

3

4

5

6

7

8

9

10

11

12


F

Exavation Bottom

B-6


Pinkish brown and reddish brown, slightly moist, hardsandy clay

CLCH

203.4'

Ele

vatio

n(F

eet)

Distance (Feet) 20 40 60 80 100 120 140 160

ExistingSFR

200

210

220

230

240

250

260S

AN

JU

AN

ST.

Pro

pert

yLin

e

Pro

pert

yLin

e

Proposed Building

Proposed Building

Line of Driveway

Proposed Grade

Slope Wash

Weathered TmvSlope Wash

Weathered Tmv

Tmv (Claystone/Siltstone)

Tmv (Claystone)

Tmv (Sandstone)

Tmv (Sandstone)

Fill

Slope Wash

1:1

Proje

ctio

n

Tem

p.Cut

Tmv (Claystone/Siltstone)

CROSS SECTION A-A'

FIGURE NO. 4


Kgr

Kc

Ksp

Qya Tp

Tmv

GEOLOGIC MAP EXCERPT

Excerpt from Preliminary Geologic Map of the El Cajon 30' x 60' Quadrangle, Southern California (Todd, 2004).

LEGEND (Localized)

Ksp = Santiago Peaks Volcanics

Kc = Cuyamaca Gabbro

Fault - Solid where well defined; dashed where inferred

FIGURE NO. 5

Kgr = Granatoid Rock

Qya = Young alluvium

Tp = Pomerado Conglomerate

Tmv = Mission Valley Formation

Unmapped Tmv ?

SUMMARY EXPLANATIONFault traces on land are indicated by solid lines where well located, by dashed lines where approximately located or inferred, and by dotted lines where

concealed by younger rocks or by lakes or bays. Fault traces are queried where continuation or existence is uncertain.FAULT CLASSIFICATION COLOR CODE (Indicating Recency of Movement)

Historic Fault (last 200 years)

FIGURE 6 - Excerpt from: 2010 Fault Activity Map of California, Geologic Data Map No. 6

Holocene fault (during past 11,700 years)

without historic record.

Late Quaternary fault (during past 700,000 years).

Quaternary fault (age undifferentiated)

Pre-Quaternary fault (older that 1.6 million years) or faultwithout recognized Quaternary displacement.

Figure No. 7

Excerpt from: DMG OPEN-FILE REPORT 95-03, LANDSLIDE HAZARDS IN THE SOUTHERNPART OF THE SAN DIEGO METROPOLITAN AREA, SAN DIEGO COUNTY, DMG OPEN-FILE REPORT 95-03,by the California, California Department of Conservation, Division Of Mines and Geology (1995)

3-1

C.W. LA MONTE COMPANY, INC.Soil and Foundation Engineers

(no scale)

Concrete Slab

Concrete or CMU Wall

Isolating JointWith Sealant

Concrete Slab

Vapor Retarder

Compacted GranularDrainage System

a.) Grade TransitionCoating or Flashing

b.) Ground SlopesAway From Wall

c.) Granular Backfill

d.) Optional Drainage Mator Isolating DrainageBoard in Place ofGranular Backfill

e.) Protection Board

f.) Waterproofing - Cont.to Bottom of Footering

g.) Filter Fabric

i.) 4" PerforatedDrain Pipe

k.) Concrete Footingj.) Water Stop

h.) Coarse DrainageGravel - Peastone

6" Min.

a.) Provides continuitybetween upper buildingenvelope weather shield& below gradewaterproofing

b.) Directs building facesheet runoff & roofgutter overspill away frombelow grade waterproofingand drainage system.

c./d.) Reduces/preventsliquid water buildupagainst wall; serves asa flow path to drain pipe.

e.) Protects membranefrom constructiondamage.

f.) Prevents moisturetransmission / penetrationthrough wall and into thebuilding.

g.) Protect soil fromcontaminating "clogging"drainage layer.

h.) Provides a flow pathfor water to exit into

drain pipe.

i.) Provides a channeledflow to the dischargesystem.

j.) Prevents moisturemigration through coldjoint @ wall / footing.

k.) Transfers wall load tosubgrade.

g.) Filter Fabric

Retaining Wall Detail

Figure 8A

Figure

SP

RE

AD

FO

OT

ING

DE

TA

IL

Mir

a D

rain

Deta

il

SLA

B

ß°°»²¼·¨ �ß� ÍÌßÒÜßÎÜ ÙÎßÜ×ÒÙ ßÒÜ ÝÑÒÍÌÎËÝÌ×ÑÒ ÍÐÛÝ×Ú×ÝßÌ×ÑÒÍ

ß°°»²¼·¨ �ß� ÍÌßÒÜßÎÜ ÙÎßÜ×ÒÙ ßÒÜ ÝÑÒÍÌÎËÝÌ×ÑÒ ÍÐÛÝ×Ú×ÝßÌ×ÑÒÍ

Ì¸»» °»½·º·½¿¬·±² °®»»²¬ ¬¸» ««¿´ ¿²¼ ³·²·³«³ ®»¯«·®»³»²¬ º±® °®±¶»½¬ ±² ©¸·½¸ ÝòÉò Ô¿ Ó±²¬»Ý±³°¿²§ · ¬¸» ¹»±¬»½¸²·½¿´ ½±²«´¬¿²¬ò Ò± ¼»ª·¿¬·±² º®±³ ¬¸»» °»½·º·½¿¬·±² ©·´´ ¾» ¿´´±©»¼ô »¨½»°¬ ©¸»®»°»½·º·½¿´´§ «°»®»¼»¼ ·² ¬¸» °®»´·³·²¿®§ ¹»±´±¹§ ¿²¼ ±·´ ®»°±®¬ ±® ·² ±¬¸»® ©®·¬¬»² ½±³³«²·½¿¬·±² ·¹²»¼ ¾§¬¸» Í±·´ Û²¹·²»»® ±® Û²¹·²»»®·²¹ Ù»±´±¹·¬ ±º ®»½±®¼ò

ÙÛÒÛÎßÔ

ßò Ì¸» Í±·´ Û²¹·²»»® ¿²¼ Û²¹·²»»®·²¹ Ù»±´±¹·¬ · ¬¸» Ñ©²»®� ±® Þ«·´¼»®� ®»°®»»²¬¿¬·ª» ±² ¬¸» Ð®±¶»½¬ò Ú±® ¬¸» °«®°±» ±º ¬¸»» °»½·º·½¿¬·±²ô °¿®¬·½·°¿¬·±² ¾§ ¬¸» Í±·´ Û²¹·²»»® ·²½´«¼» ¬¸¿¬ ±¾»®ª¿¬·±² °»®º±®³»¼¾§ ¿²§ °»®±² ±® °»®±² »³°´±§»¼ ¾§ô ¿²¼ ®»°±²·¾´» ¬±ô ¬¸» ´·½»²»¼ Ý·ª·´ Û²¹·²»»® ·¹²·²¹ ¬¸» ±·´®»°±®¬ò

Þò ß´´ ½´»¿®·²¹ô ·¬» °®»°¿®¿¬·±²ô ±® »¿®¬¸©±®µ °»®º±®³»¼ ±² ¬¸» °®±¶»½¬ ¸¿´´ ¾» ½±²¼«½¬»¼ ¾§ ¬¸» Ý±²¬®¿½¬±®«²¼»® ¬¸» «°»®ª··±² ±º ¬¸» Í±·´ Û²¹·²»»®ò

Ýò ×¬ · ¬¸» Ý±²¬®¿½¬±®� ®»°±²·¾·´·¬§ ¬± °®»°¿®» ¬¸» ¹®±«²¼ «®º¿½» ¬± ®»½»·ª» ¬¸» º·´´ ¬± ¬¸» ¿¬·º¿½¬·±² ±º ¬¸» Í±·´ Û²¹·²»»® ¿²¼ ¬± °´¿½»ô °®»¿¼ô ³·¨ô ©¿¬»®ô ¿²¼ ½±³°¿½¬ ¬¸» º·´´ ·² ¿½½±®¼¿²½» ©·¬¸ ¬¸» °»½·º·½¿¬·±² ±º¬¸» Í±·´ Û²¹·²»»®ò Ì¸» Ý±²¬®¿½¬±® ¸¿´´ ¿´± ®»³±ª» ¿´´ ³¿¬»®·¿´ ½±²·¼»®»¼ «²¿¬·º¿½¬±®§ ¾§ ¬¸» Í±·´Û²¹·²»»®ò

Üò ×¬ · ¿´± ¬¸» Ý±²¬®¿½¬±®� ®»°±²·¾·´·¬§ ¬± ¸¿ª» «·¬¿¾´» ¿²¼ «ºº·½·»²¬ ½±³°¿½¬·±² »¯«·°³»²¬ ±² ¬¸» ¶±¾ ·¬» ¬± ¸¿²¼´» ¬¸» ¿³±«²¬ ±º º·´´ ¾»·²¹ °´¿½»¼ò ×º ²»½»¿®§ô »¨½¿ª¿¬·±² »¯«·°³»²¬ ©·´´ ¾» ¸«¬ ¼±©² ¬± °»®³·¬½±³°´»¬·±² ±º ½±³°¿½¬·±²ò Í«ºº·½·»²¬ ©¿¬»®·²¹ ¿°°¿®¿¬« ©·´´ ¿´± ¾» °®±ª·¼»¼ ¾§ ¬¸» Ý±²¬®¿½¬±®ô ©·¬¸ ¼«»½±²·¼»®¿¬·±² º±® ¬¸» º·´´ ³¿¬»®·¿´ô ®¿¬» ±º °´¿½»³»²¬ô ¿²¼ ¬·³» ±º §»¿®ò

Ûò ß º·²¿´ ®»°±®¬ ¸¿´´ ¾» ·«»¼ ¾§ ¬¸» Í±·´ Û²¹·²»»® ¿¬¬»¬·²¹ ¬± ¬¸» Ý±²¬®¿½¬±®� ½±²º±®³¿²½» ©·¬¸ ¬¸»» °»½·º·½¿¬·±²ò

Í×ÌÛ ÐÎÛÐßÎßÌ×ÑÒ

ßò ß´´ ª»¹»¬¿¬·±² ¿²¼ ¼»´»¬»®·±« ³¿¬»®·¿´ ¸¿´´ ¾» ¼·°±»¼ ±º ±ºº ·¬»ò Ì¸· ®»³±ª¿´ ¸¿´´ ¾» ½±²½´«¼»¼ °®·±® ¬±°´¿½·²¹ º·´´ò

Þò Í±·´ô ¿´´«ª·«³ô ±® ¾»¼®±½µ ³¿¬»®·¿´ ¼»¬»®³·²»¼ ¾§ ¬¸» Í±·´ Û²¹·²»»®ô ¿ ¾»·²¹ «²«·¬¿¾´» º±® °´¿½»³»²¬ ·²½±³°¿½¬»¼ º·´´ ¸¿´´ ¾» ®»³±ª»¼ º®±³ ¬¸» ·¬»ò Ì¸» Í±·´ Û²¹·²»»® ³«¬ ¿°°®±ª» ¿²§ ³¿¬»®·¿´ ·²½±®°±®¿¬»¼¿ ¿ °¿®¬ ±º ¿ ½±³°¿½¬»¼ º·´´ò

Ýò ßº¬»® ¬¸» ¹®±«²¼ «®º¿½» ¬± ®»½»·ª» º·´´ ¸¿ ¾»»² ½´»¿®»¼ô ·¬ ¸¿´´ ¾» ½¿®·º·»¼ô ¼·½»¼ô ±® ¾´¿¼»¼ ¾§ ¬¸»Ý±²¬®¿½¬±® «²¬·´ ·¬ · «²·º±®³ ¿²¼ º®»» º®±³ ®«¬ô ¸±´´±©ô ¸«³³±½µô ±® ±¬¸»® «²»ª»² º»¿¬«®» ©¸·½¸ ³¿§°®»ª»²¬ «²·º±®³ ½±³°¿½¬·±²ò

Ì¸» ½¿®·º·»¼ ¹®±«²¼ «®º¿½» ¸¿´´ ¬¸»² ¾» ¾®±«¹¸¬ ¬± ±°¬·³«³ ³±·¬«®»ô ³·¨»¼ ¿ ®»¯«·®»¼ô ¿²¼ ½±³°¿½¬»¼¿ °»½·º·»¼ò ×º ¬¸» ½¿®·º·»¼ ¦±²» · ¹®»¿¬»® ¬¸¿² ïî ·²½¸» ·² ¼»°¬¸ô ¬¸» »¨½» ¸¿´´ ¾» ®»³±ª»¼ ¿²¼ °´¿½»¼·² ´·º¬ ®»¬®·½¬»¼ ¬± ê ·²½¸»ò

Ð®·±® ¬± °´¿½·²¹ º·´´ô ¬¸» ¹®±«²¼ «®º¿½» ¬± ®»½»·ª» º·´´ ¸¿´´ ¾» ·²°»½¬»¼ô ¬»¬»¼ ¿ ²»½»¿®§ô ¿²¼ ¿°°®±ª»¼¾§ ¬¸» Í±·´ Û²¹·²»»®ò

Üò ß²§ «²¼»®¹®±«²¼ ¬®«½¬«®» «½¸ ¿ ½»°±±´ô ½·¬»®²ô ³·²·²¹ ¸¿º¬ô ¬«²²»´ô »°¬·½ ¬¿²µô ©»´´ô °·°»´·²»ô ±® ±¬¸»® ¿®» ¬± ¾» ®»³±ª»¼ ±® ¬®»¿¬»¼ ·² ¿ ³¿²²»® °®»½®·¾»¼ ¾§ ¬¸» Í±·´ Û²¹·²»»® ¿²¼ ñ±® ¹±ª»®²·²¹¿¹»²½§ò

Ûò ×² ±®¼»® ¬± °®±ª·¼» «²·º±®³ ¾»¿®·²¹ ½±²¼·¬·±² ·² ½«¬óº·´´ ¬®¿²·¬·±² ´±¬ ¿²¼ ©¸»®» ½«¬ ´±¬ ¿®» °¿®¬·¿´´§ ·²±·´ô ½±´´«ª·«³ô ±® «²ó©»¿¬¸»®»¼ ¾»¼®±½µ ³¿¬»®·¿´ô ¬¸» ¾»¼®±½µ °±®¬·±² ±º ¬¸» ´±¬ »¨¬»²¼·²¹ ¿ ³·²·³«³ ±º íº»»¬ ±«¬·¼» ±º ¾«·´¼·²¹ ´·²» ¸¿´´ ¾» ±ª»® »¨½¿ª¿¬»¼ ¿ ³·²·³«³ ±º í º»»¬ ¿²¼ ®»°´¿½»¼ ©·¬¸ ½±³°¿½¬»¼ º·´´ò

ß°°»²¼·¨ ß Í¬¿²¼¿®¼ Ù®¿¼·²¹ ¿²¼ Ý±²¬®«½¬·±² Í°»½·º·½¿¬·±² Ð¿¹» î

ÝÑÓÐßÝÌÛÜ Ú×ÔÔÍ

ßò ß²§ ³¿¬»®·¿´ ·³°±®¬»¼ ±® »¨½¿ª¿¬»¼ ±² ¬¸» °®±°»®¬§ ³¿§ ¾» «¬·´·¦»¼ ·² ¬¸» º·´´ô °®±ª·¼»¼ »¿½¸ ³¿¬»®·¿´¸¿ ¾»»² ¼»¬»®³·²»¼ ¬± ¾» «·¬¿¾´» ¾§ ¬¸» Í±·´ Û²¹·²»»®ò Î±±¬ô ¬®»» ¾®¿²½¸»ô ¿²¼ ±¬¸»® ³¿¬¬»® ³·»¼¼«®·²¹ ½´»¿®·²¹ ¸¿´´ ¾» ®»³±ª»¼ º®±³ ¬¸» º·´´ ¿ ¼·®»½¬»¼ ¾§ ¬¸» Í±·´ Û²¹·²»»®ò

Þò Î±½µ º®¿¹³»²¬ ´» ¬¸¿² ê ·²½¸» ·² ¼·¿³»¬»® ³¿§ ¾» «¬·´·¦»¼ ·² ¬¸» º·´´ô °®±ª·¼»¼æ

ïò Ì¸»§ ¿®» ²±¬ °´¿½»¼ ·² ½±²½»²¬®¿¬»¼ °±½µ»¬òîò Ì¸»®» · ¿ «ºº·½·»²¬ °»®½»²¬¿¹» ±º º·²»ó¹®¿·²»¼ ³¿¬»®·¿´ ¬± «®®±«²¼ ¬¸» ®±½µòíò Ì¸» Í±·´ Û²¹·²»»® ¸¿´´ «°»®ª·» ¬¸» ¼·¬®·¾«¬·±² ±º ®±½µò

Ýò Î±½µ ¹®»¿¬»® ¬¸¿² ê ·²½¸» ·² ¼·¿³»¬»® ¸¿´´ ¾» ¬¿µ»² ±ºº ·¬»ô ±® °´¿½»¼ ·² ¿½½±®¼¿²½» ©·¬¸ ¬¸»®»½±³³»²¼¿¬·±² ±º ¬¸» Í±·´ Û²¹·²»»® ·² ¿®»¿ ¼»·¹²¿¬»¼ ¿ «·¬¿¾´» º±® ®±½µ ¼·°±¿´ò

Üò Ó¿¬»®·¿´ ¬¸¿¬ · °±²¹§ô «¾¶»½¬ ¬± ¼»½¿§ ±® ±¬¸»®©·» ½±²·¼»®»¼ «²«·¬¿¾´» ¸±«´¼ ²±¬ ¾» «»¼ ·² ¬¸»½±³°¿½¬»¼ º·´´ò

Ûò Î»°®»»²¬¿¬·ª» ¿³°´» ±º ³¿¬»®·¿´ ¬± ¾» «¬·´·¦»¼ ¿ ½±³°¿½¬»¼ º·´´ ¸¿´´ ¾» ¿²¿´§¦»¼ ¾§ ¬¸» ´¿¾±®¿¬±®§±º ¬¸» Í±·´ Û²¹·²»»® ¬± ¼»¬»®³·²» ¬¸»·® °¸§·½¿´ °®±°»®¬·»ò ×º ¿²§ ³¿¬»®·¿´ ±¬¸»® ¬¸¿² ¬¸¿¬ °®»ª·±«´§¬»¬»¼ · »²½±«²¬»®»¼ ¼«®·²¹ ¹®¿¼·²¹ô ¬¸» ¿°°®±°®·¿¬» ¿²¿´§· ±º ¬¸· ³¿¬»®·¿´ ¸¿´´ ¾» ½±²¼«½¬»¼ ¾§ ¬¸»Í±·´ Û²¹·²»»® ¿ ±±² ¿ °±·¾´»ò

Úò Ó¿¬»®·¿´ «»¼ ·² ¬¸» ½±³°¿½¬·±² °®±½» ¸¿´´ ¾» »ª»²´§ °®»¿¼ô ©¿¬»®»¼ °®±½»»¼ô ¿²¼ ½±³°¿½¬»¼ ·²¬¸·² ´·º¬ ²±¬ ¬± »¨½»»¼ ê ·²½¸» ·² ¬¸·½µ²» ¬± ±¾¬¿·² ¿ «²·º±®³´§ ¼»²» ´¿§»®ò Ì¸» º·´´ ¸¿´´ ¾» °´¿½»¼¿²¼ ½±³°¿½¬»¼ ±² ¿ ¸±®·¦±²¬¿´ °´¿²»ô «²´» ±¬¸»®©·» ¿°°®±ª»¼ ¾§ ¬¸» Í±·´ Û²¹·²»»®ò

Ùò ×º ¬¸» ³±·¬«®» ½±²¬»²¬ ±® ®»´¿¬·ª» ¼»²·¬§ ª¿®·» º®±³ ¬¸¿¬ ®»¯«·®»¼ ¾§ ¬¸» Í±·´ Û²¹·²»»®ô ¬¸»Ý±²¬®¿½¬±® ¸±«´¼ ®»ó©±®µ ¬¸» º·´´ «²¬·´ ¬¸» Í±·´ Û²¹·²»»® ¿°°®±ª» ·¬ò

Øò Û¿½¸ ´¿§»® ¸¿´´ ¾» ½±³°¿½¬»¼ ¬± çð °»®½»²¬ ±º ¬¸» ³¿¨·³«³ ¼»²·¬§ ·² ½±³°´·¿²½» ©·¬¸ ¬¸» ¬»¬·²¹³»¬¸±¼ °»½·º·»¼ ¾§ ¬¸» ½±²¬®±´´·²¹ ¹±ª»®²³»²¬¿´ ¿¹»²½§ò ø×² ¹»²»®¿´ô ßÍÌÓ Üóïëëéóçïô ¬¸» º·ª»ó´¿§»®³»¬¸±¼ ©·´´ ¾» «»¼ò÷

×º ½±³°¿½¬·±² ¬± ¿ ´»»® °»®½»²¬¿¹» · ¿«¬¸±®·¦»¼ ¾§ ¬¸» ½±²¬®±´´·²¹ ¹±ª»®²³»²¬¿´ ¿¹»²½§ ¾»½¿«» ±º ¿°»½·º·½ ´¿²¼ «» ±® »¨°¿²·ª» ±·´ ½±²¼·¬·±²ô ¬¸» ¿®»¿ ¬± ®»½»·ª» º·´´ ½±³°¿½¬»¼ ¬± ´» ¬¸¿² çð °»®½»²¬¸¿´´ »·¬¸»® ¾» ¼»´·²»¿¬»¼ ±² ¬¸» ¹®¿¼·²¹ °´¿² ±® ¿°°®±°®·¿¬» ®»º»®»²½» ³¿¼» ¬± ¬¸» ¿®»¿ ·² ¬¸» ±·´®»°±®¬ò

Øò ß´´ º·´´ ¸¿´´ ¾» µ»§»¼ ¿²¼ ¾»²½¸»¼ ¬¸®±«¹¸ ¿´´ ¬±°±·´ô ½±´´«ª·«³ô ¿´´«ª·«³ ±® ½®»»° ³¿¬»®·¿´ô ·²¬±±«²¼ ¾»¼®±½µ ±® º·®³ ³¿¬»®·¿´ »¨½»°¬ ©¸»®» ¬¸» ´±°» ®»½»·ª·²¹ º·´´ »¨½»»¼ ¿ ®¿¬·± ±º º·ª» ¸±®·¦±²¬¿´¬± ±²» ª»®¬·½¿´ô ·² ¿½½±®¼¿²½» ©·¬¸ ¬¸» ®»½±³³»²¼¿¬·±² ±º ¬¸» Í±·´ Û²¹·²»»®ò

×ò Ì¸» µ»§ º±® ¸·´´·¼» º·´´ ¸±«´¼ ¾» ¿ ³·²·³«³ ±º ïë º»»¬ ·² ©·¼¬¸ ¿²¼ ©·¬¸·² ¾»¼®±½µ ±® ·³·´¿®³¿¬»®·¿´ô «²´» ±¬¸»®©·» °»½·º·»¼ ·² ¬¸» ±·´ ®»°±®¬ò

Õò Í«¾¼®¿·²¿¹» ¼»ª·½» ¸¿´´ ¾» ½±²¬®«½¬»¼ ·² ½±³°´·¿²½» ©·¬¸ ¬¸» ±®¼·²¿²½» ±º ¬¸» ½±²¬®±´´·²¹¹±ª»®²³»²¬¿´ ¿¹»²½§ô ±® ©·¬¸ ¬¸» ®»½±³³»²¼¿¬·±² ±º ¬¸» Í±·´ Û²¹·²»»® ±® Û²¹·²»»®·²¹ Ù»±´±¹·¬ò

Ôò Ì¸» ½±²¬®¿½¬±® ©·´´ ¾» ®»¯«·®»¼ ¬± ±¾¬¿·² ¿ ³·²·³«³ ®»´¿¬·ª» ½±³°¿½¬·±² ±º çð °»®½»²¬ ±«¬ ¬± ¬¸» º·²·¸´±°» º¿½» ±º º·´´ ´±°»ô ¾«¬¬®»»ô ¿²¼ ¬¿¾·´·¦¿¬·±² º·´´ò Ì¸· ³¿§ ¾» ¿½¸·»ª»¼ ¾§ »·¬¸»® ±ª»®¾«·´¼·²¹¬¸» ´±°» ¿²¼ ½«¬¬·²¹ ¾¿½µ ¬± ¬¸» ½±³°¿½¬»¼ ½±®»ô ±® ¾§ ¼·®»½¬ ½±³°¿½¬·±² ±º ¬¸» ´±°» º¿½» ©·¬¸ «·¬¿¾´»»¯«·°³»²¬ô ±® ¾§ ¿²§ ±¬¸»® °®±½»¼«®» ©¸·½¸ °®±¼«½» ¬¸» ®»¯«·®»¼ ½±³°¿½¬·±²ò

ß°°»²¼·¨ ß Í¬¿²¼¿®¼ Ù®¿¼·²¹ ¿²¼ Ý±²¬®«½¬·±² Í°»½·º·½¿¬·±² Ð¿¹» í

Óò ß´´ º·´´ ´±°» ¸±«´¼ ¾» °´¿²¬»¼ ±® °®±¬»½¬»¼ º®±³ »®±·±² ±® ¾§ ±¬¸»® ³»¬¸±¼ °»½·º·»¼ ·² ¬¸» ±·´®»°±®¬ò

Òò Ú·´´ó±ª»®ó½«¬ ´±°» ¸¿´´ ¾» °®±°»®´§ µ»§»¼ ¬¸®±«¹¸ ¬±°±·´ô ½±´´«ª·«³ ±® ½®»»° ³¿¬»®·¿´ ·²¬± ®±½µ ±®º·®³ ³¿¬»®·¿´ô ¿²¼ ¬¸» ¬®¿²·¬·±² ¸¿´´ ¾» ¬®·°°»¼ ±º ¿´´ ±·´ °®·±® ¬± °´¿½·²¹ º·´´ò

ÝËÌ ÍÔÑÐÛÍ

ßò Ì¸» Û²¹·²»»®·²¹ Ù»±´±¹·¬ ¸¿´´ ·²°»½¬ ¿´´ ½«¬ ´±°» ¿¬ ª»®¬·½¿´ ·²¬»®ª¿´ ²±¬ »¨½»»¼·²¹ ïð º»»¬ò

Þò ×º ¿²§ ½±²¼·¬·±² ²±¬ ¿²¬·½·°¿¬»¼ ·² ¬¸» °®»´·³·²¿®§ ®»°±®¬ «½¸ ¿ °»®½¸»¼ ©¿¬»®ô »»°¿¹»ô ´»²¬·½«´¿® ±®½±²º·²»¼ ¬®¿¬¿ ±º ¿ °±¬»²¬·¿´´§ ¿¼ª»®» ²¿¬«®»ô «²º¿ª±®¿¾´§ ·²½´·²»¼ ¾»¼¼·²¹ô ¶±·²¬ ±® º¿«´¬ °´¿²» ¿®»»²½±«²¬»®»¼ ¼«®·²¹ ¹®¿¼·²¹ô ¬¸»» ½±²¼·¬·±² ¸¿´´ ¾» ¿²¿´§¦»¼ ¾§ ¬¸» Û²¹·²»»®·²¹ Ù»±´±¹·¬ ¿²¼ Í±·´Û²¹·²»»®ô ¿²¼ ®»½±³³»²¼¿¬·±² ¸¿´´ ¾» ³¿¼» ¬± ¬®»¿¬ ¬¸»» °®±¾´»³ò

Ýò Ý«¬ ´±°» ¬¸¿¬ º¿½» ·² ¬¸» ¿³» ¼·®»½¬·±² ¿ ¬¸» °®»ª¿·´·²¹ ¼®¿·²¿¹» ¸¿´´ ¾» °®±¬»½¬»¼ º®±³ ´±°» ©¿¸ ¾§ ¿²±²ó»®±¼·¾´» ·²¬»®½»°¬±® ©¿´» °´¿½»¼ ¿¬ ¬¸» ¬±° ±º ¬¸» ´±°»ò

Ë²´» ±¬¸»®©·» °»½·º·»¼ ·² ¬¸» ±·´ ¿²¼ ¹»±´±¹·½¿´ ®»°±®¬ô ²± ½«¬ ´±°» ¸¿´´ ¾» »¨½¿ª¿¬»¼ ¸·¹¸»® ±®¬»»°»® ¬¸¿² ¬¸¿¬ ¿´´±©»¼ ¾§ ¬¸» ±®¼·²¿²½» ±º ½±²¬®±´´·²¹ ¹±ª»®²³»²¬¿´ ¿¹»²½·»ò

Ü®¿·²¿¹» ¬»®®¿½» ¸¿´´ ¾» ½±²¬®«½¬»¼ ·² ½±³°´·¿²½» ©·¬¸ ¬¸» ±®¼·²¿²½» ±º ½±²¬®±´´·²¹ ¹±ª»®²³»²¬¿´¿¹»²½·»ô ±® ©·¬¸ ¬¸» ®»½±³³»²¼¿¬·±² ±º ¬¸» Í±·´ Û²¹·²»»® ±® Û²¹·²»»®·²¹ Ù»±´±¹·¬ò

ÙÎßÜ×ÒÙ ÝÑÒÌÎÑÔ

ßò Ñ¾»®ª¿¬·±² ±º ¬¸» º·´´ °´¿½»³»²¬ ¸¿´´ ¾» °®±ª·¼»¼ ¾§ ¬¸» Í±·´ Û²¹·²»»® ¼«®·²¹ ¬¸» °®±¹®» ±º ¹®¿¼·²¹ò

Þò ×² ¹»²»®¿´ô ¼»²·¬§ ¬»¬ ¸±«´¼ ¾» ³¿¼» ¿¬ ·²¬»®ª¿´ ²±¬ »¨½»»¼·²¹ î º»»¬ ±º º·´´ ¸»·¹¸¬ ±® »ª»®§ ëðð ½«¾·½§¿®¼ ±º º·´´ °´¿½»³»²¬ò Ì¸· ½®·¬»®·¿ ©·´´ ª¿®§ô ¼»°»²¼·²¹ ±² ±·´ ½±²¼·¬·±² ¿²¼ ¬¸» ·¦» ±º ¬¸» ¶±¾ò ×² ¿²§»ª»²¬ô ¿² ¿¼»¯«¿¬» ²«³¾»® ±º º·»´¼ ¼»²·¬§ ¬»¬ ¸¿´´ ¾» ³¿¼» ¬± ª»®·´§ ¬¸¿¬ ¬¸» ®»¯«·®»¼ ½±³°¿½¬·±² · ¾»·²¹¿½¸·»ª»¼ò

Ýò Ü»²·¬§ ¬»¬ ³¿§ ¿´± ¾» ½±²¼«½¬»¼ ±² ¬¸» «®º¿½» ³¿¬»®·¿´ ¬± ®»½»·ª» º·´´ ¿ ¼»¬»®³·²»¼ ¾§ ¬¸» Í±·´Û²¹·²»»®ò

Üò ß´´ ½´»¿²ó±«¬ô °®±½»»¼ ¹®±«²¼ ¬± ®»½»·ª» º·´´ô µ»§ »¨½¿ª¿¬·±²ô «¾¼®¿·²ô ¿²¼ ®±½µ ¼·°±¿´ ³«¬ ¾»·²°»½¬»¼ ¿²¼ ¿°°®±ª»¼ ¾§ ¬¸» Í±·´ Û²¹·²»»® ±® Û²¹·²»»®·²¹ Ù»±´±¹·¬ °®·±® ¬± °´¿½·²¹ ¿²§ º·´´ò ×¬ ¸¿´´ ¾»¬¸» Ý±²¬®¿½¬±®� ®»°±²·¾·´·¬§ ¬± ²±¬·º§ ¬¸» Í±·´ Û²¹·²»»® ©¸»² «½¸ ¿®»¿ ¿®» ®»¿¼§ º±® ·²°»½¬·±²ò

ÝÑÒÍÌÎËÝÌ×ÑÒ ÝÑÒÍ×ÜÛÎßÌ×ÑÒÍ

ßò Ì¸» Ý±²¬®¿½¬±® ¸¿´´ °®±ª·¼» ²»½»¿®§ »®±·±² ½±²¬®±´ ³»¿«®»ô ¼«®·²¹ ¹®¿¼·²¹ ¿²¼ °®·±® ¬± ¬¸» ½±³°´»¬·±²¿²¼ ½±²¬®«½¬·±² ±º °»®³¿²»²¬ ¼®¿·²¿¹» ½±²¬®±´ò

Þò Ë°±² ½±³°´»¬·±² ±º ¹®¿¼·²¹ ¿²¼ ¬»®³·²¿¬·±² ±º ·²°»½¬·±² ¾§ ¬¸» Í±·´ Û²¹·²»»®ô ²± º«®¬¸»® º·´´·²¹ ±®»¨½¿ª¿¬·²¹ô ·²½´«¼·²¹ ¬¸¿¬ ²»½»¿®§ º±® º±±¬·²¹ô º±«²¼¿¬·±²ô ´¿®¹» ¬®»» ©»´´ô ®»¬¿·²·²¹ ©¿´´ô ±® ±¬¸»®º»¿¬«®» ¸¿´´ ¾» °»®º±®³»¼ ©·¬¸±«¬ ¬¸» ¿°°®±ª¿´ ±º ¬¸» Í±·´ Û²¹·²»»® ±® Û²¹·²»»®·²¹ Ù»±´±¹·¬ò

Ýò Ý¿®» ¸¿´´ ¾» ¬¿µ»² ¾§ ¬¸» Ý±²¬®¿½¬±® ¼«®·²¹ º·²¿´ ¹®¿¼·²¹ ¬± °®»»®ª» ¿²§ ¾»®³ô ¼®¿·²¿¹» ¬»®®¿½»ô·²¬»®½»°¬±® ©¿´»ô ±® ±¬¸»® ¼»ª·½» ±º °»®³¿²»²¬ ²¿¬«®» ±² ±® ¿¼¶¿½»²¬ ¬± ¬¸» °®±°»®¬§ò

Üò ×² ¬¸» »ª»²¬ ¬¸¿¬ ¬»³°±®¿®§ ®¿³° ±® °¿¼ ¿®» ½±²¬®«½¬»¼ ±º «²½±²¬®±´´»¼ º·´´ ±·´ ¼«®·²¹ ¿ º«¬«®» ¹®¿¼·²¹±°»®¿¬·±²ô ¬¸» ´±½¿¬·±² ¿²¼ »¨¬»²¬ ±º ¬¸» ´±±» º·´´ ±·´ ¸¿´´ ¾» ²±¬»¼ ¾§ ¬¸» ±²ó·¬» ®»°®»»²¬¿¬·ª» ±º ¿¯«¿´·º·»¼ ±·´ »²¹·²»»®·²¹ º·®³ò Ì¸»» ³¿¬»®·¿´ ¸¿´´ ¾» ®»³±ª»¼ ¿²¼ °®±°»®´§ ®»½±³°¿½¬»¼ °®·±® ¬±½±³°´»¬·±² ±º ¹®¿¼·²¹ ±°»®¿¬·±²ò

Ûò É¸»®» ²±¬ «°»®»¼»¼ ¾§ °»½·º·½ ®»½±³³»²¼¿¬·±² °®»»²¬»¼ ·² ¬¸· ®»°±®¬ô ¬®»²½¸»ô »¨½¿ª¿¬·±²ô ¿²¼¬»³°±®¿®§ ´±°» ¿¬ ¬¸» «¾¶»½¬ ·¬» ¸¿´´ ¾» ½±²¬®«½¬»¼ ·² ¿½½±®¼¿²½» ©·¬¸ »½¬·±² ïëìï ±º Ì·¬´» èôÝ±²¬®«½¬·±² Í¿º»¬§ Ñ®¼»®ô ·«»¼ ¾§ ÑÍØßò

ß°°»²¼·¨ ß Í¬¿²¼¿®¼ Ù®¿¼·²¹ ¿²¼ Ý±²¬®«½¬·±² Í°»½·º·½¿¬·±² Ð¿¹» ì

ßÐÐÛÒÜ×È � Þ� ËÒ×Ú×ÛÜ ÍÑ×Ô ÝÔßÍÍ×Ú×ÝßÌ×ÑÒ ÝØßÎÌ

ÍÑ× Ô ÜÛÍÝ Î× ÐÌ× ÑÒ

× ò ÝÑßÎÍÛ ÙÎß×ÒÛÜæ Ó±®» ¬¸¿² ¸¿´º ±º ³¿¬»®·¿´ · ´¿®¹»® ¬¸¿² Ò±ò îðð ·»ª» ·¦»ò

ÙÎßÊÛÔÍæ Ó±®» ¬¸¿² ¸¿´º ±º ½±¿®» º®¿½¬·±² · ´¿®¹»® ¬¸¿² Ò±ò ì ·»ª» ·¦» ¾«¬ ³¿´´»® ¬¸¿² íþò

ÙÎÑËÐ ÍÇÓÞÑÔ ÌÇÐ×ÝßÔ ÒßÓÛÍ

ÝÔÛßÒ ÙÎßÊÛÔÍ ÙÉ É»´´ ¹®¿¼»¼ ¹®¿ª»´ô ¹®¿ª»´ó¿²¼ ³·¨¬«®»ô ´·¬¬´» ±® ²± º·²»ò

ÙÐ Ð±±®´§ ¹®¿¼»¼ ¹®¿ª»´ô ¹®¿ª»´ ¿²¼ ³·¨¬«®»ô ´·¬¬´» ±® ²± º·²»

ÙÎßÊÛÔÍ É×ÌØ Ú×ÒÛÍ ÙÓ Í·´¬§ ¹®¿ª»´ô °±±®´§ ¹®¿¼»¼ ¹®¿ª»´ó ¿²¼ó·´¬ ³·¨¬«®»

øß°°®»½·¿¾´» ¿³±«²¬ ±º º·²»÷ÙÝ Ý´¿§»§ ¹®¿ª»´ô °±±®´§ ¹®¿¼»¼ ¹®¿ª»´ ¿²¼ô ½´¿§ ³·¨¬«®»ò

òÍßÒÜÍæ Ó±®» ¬¸¿² ¸¿´º ±º ½±¿®» º®¿½¬·±² · ³¿´´»® ¬¸¿² Ò±ò ì ·»ª» ·¦»

ÝÔÛßÒ ÍßÒÜÍ ÍÉ É»´´ ¹®¿¼»¼ ¿²¼ô ¹®¿ª»´´§ ¿²¼ô ´·¬¬´» ±® ²± º·²»

òÍÐ Ð±±®´§ ¹®¿¼»¼ ¿²¼ô ¹®¿ª»´´§ ¿²¼ô ´·¬¬´» ±® ²± º·²»ò

ò

ÍßÒÜÍ É×ÌØ Ú×ÒÛÍ ÍÓ Í·´¬§ ¿²¼ô °±±®´§ ¹®¿¼»¼ ¿²¼ ¿²¼ ·´¬§ ³·¨¬«®»ò

øß°°®»½·¿¾´» ¿³±«²¬ ±º º·²»

ÍÝ Ý´¿§»§ ¿²¼ô °±±®´§ ¹®¿¼»¼ ¿²¼ ¿²¼ ½´¿§ ³·¨¬«®»

ò××ò Ú×ÒÛ ÙÎß×ÒÛÜæ Ó±®» ¬¸¿² ¸¿´º ±º ³¿¬»®·¿´ · ³¿´´»® ¬¸¿² Ò±ò îðð ·»ª» ·¦»

ò

Í×ÔÌÍ ßÒÜ ÝÔßÇÍ ÓÔ ×²±®¹¿²·½ ·´¬ ¿²¼ ª»®§ º·²» ¿²¼ô ®±½µ º´±«®ô ¿²¼§ ·´¬

ó ±® ½´¿§»§ó·´¬ ©·¬¸ ´·¹¸¬ °´¿¬·½·¬§ò

Ô·¯«·¼ Ô·³·¬ ÝÔ ×²±®¹¿²·½ ½´¿§ ±º ´±© ¬± ³»¼·«³ °´¿¬·½·¬§ô

Ô» ¬¸¿² ëð ¹®¿ª»´´§ ½´¿§ô ¿²¼§ ½´¿§ô ·´¬§ ½´¿§ô ´»¿² ½´¿§

ÑÔ Ñ®¹¿²·½ ·´¬ ¿²¼ ±®¹¿²·½ ·´¬§ ½´¿§ ±º ´±© °´¿¬·½·¬§

ò

Í×ÔÌÍ ßÒÜ ÝÔßÇÍ ÓØ ×²±®¹¿²·½ ·´¬ô ³·½¿½»±« ±® ¼·¿¬±³¿½»±« º·²» ¿²¼§ ±® ·´¬§

±·´ô »´¿¬·½ ·´¬

Ô·¯«·¼ Ô·³·¬ ÝØ ×²±®¹¿²·½ ½´¿§ ±º ¸·¹¸ °´¿¬·½·¬§ô º¿¬ ½´¿§ò

¹®»¿¬»® ¬¸¿² ëðÑØ Ñ®¹¿²·½ ½´¿§ ±º ³»¼·«³ ¬± ¸·¹¸ °´¿¬·½·¬§ò

Ø×ÙØÔÇ ÑÎÙßÒ×Ý ÍÑ×ÔÍ

ÐÌ Ð»¿¬ ¿²¼ ±¬¸»® ¸·¹¸´§ ±®¹¿²·½ ±·´ò

Documents

Soil and Foundation Engineers REPORT OF LIMITED ......8265 COMMERCIAL STREET #12 LA MESA, CALIFORNIA 91941 Phone: (619) 462-9861 Fax: (619) 462-9859 July 31, 2015 TO: Fred Schmidt