LANDFILL E LAND USE CONTROL

SITE-SPECIFIC ADDENDUM TO THE PRESIDIO TRUST LAND USE CONTROLS MASTER REFERENCE REPORT

Presidio of San Francisco, California

CONTENTS

August 2012 i Landfill E Land Use Control

Page

1.  INTRODUCTION AND DECISION DOCUMENT 1 

2.  AREA INCLUDED IN THE LAND USE CONTROL 1 

3.  REMEDIATION SUMMARY AND REMAINING CHEMICALS OF CONCERN 1 

3.1  Site History and Remedial Activities .............................................................................. 1 3.2  Residual Chemicals that Necessitate the LUC ................................................................ 3 

4.  SITE-SPECIFIC LAND USE RESTRICTIONS 3 

5.  INSPECTION, MAINTENANCE, AND REPAIR REQUIREMENTS 4 

6.  REFERENCES 5 

Tables:

1. COCs Remaining in Landfill E Land Use Control Area Soil 2. Coordinates for Landfill E Confirmation Sampling Locations 3. Landfill E Land Use Controls

Figures:

1. Landfill E Land Use Control Area 2. Landfill E Confirmation Sampling Locations

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1. INTRODUCTION AND DECISION DOCUMENT This Site-Specific addendum to the Presidio Trust Land Use Control Master Reference Report (LUCMRR) has been prepared for Landfill E (LFE or the Site) as an addendum to the Presidio Trust Land Use Controls Master Reference Report, Presidio of San Francisco, California (LUCMRR) (Presidio Trust, 2009) pursuant to the Final Feasibility Study/Remedial Action Plan for Landfill E, Presidio of San Francisco, California (Final FS/RAP) (Geosyntec, 2011a), which was approved by the Department of Toxic Substances Control on June 16, 2011. 2. AREA INCLUDED IN THE LAND USE CONTROL The Final FS/RAP defined the area that encompasses LFE. The LFE Land Use Control (LUC) Area is defined in this addendum based on a survey of post-remediation Site conditions as documented in the Construction Completion Report for Landfill E, Presidio of San Francisco, California (CCR) (Geosyntec, 2012a). Figure 1 shows the location and extent of the LFE LUC Area. The LFE LUC Area is located in Area B of the Presidio. 3. REMEDIATION SUMMARY AND REMAINING CHEMICALS OF CONCERN This section describes remedial actions that have been implemented at LFE and identifies chemicals of concern (COCs) that were detected above unrestricted cleanup levels (CULs) for LFE. Detailed summaries of remedial actions and remaining chemical concentrations for LFE are provided in the Final FS/RAP (Geosyntec, 2011a) and the CCR (Geosyntec, 2012a).

3.1 Site History and Remedial Activities LFE was created by filling a portion of the western drainage of the Tennessee Hollow area, previously used as a small-arms firing range designated the Barnard Avenue Protected Range (BAPR). LFE is approximately 4.6 acres in area and is bounded by Barnard Avenue on the northwest and Quarry Road on the southwest. Fernandez Street is approximately 500 feet to the north (Geosyntec, 2011a). LFE contains soil mixed with building debris, municipal-type solid waste, and chemical waste. The total landfill volume at LFE is estimated to be 107,500 cubic yards. LFE has a maximum depth of fill of approximately 39 feet below ground surface (ft bgs) in the north-central portion, and pinches out at the canyon walls (Geosyntec, 2011a). Prior to remediation, surface water drainage was conveyed in a southwest-northwest direction through LFE in a subsurface pipe.

August 2012 2 Landfill E Land Use Control

The Trust completed remedial action at LFE required by the Final FS/RAP (Geosyntec, 2011a) in the summer of 2011. The remedial action activities are documented in the CCR (Geosyntec, 2012a). The following remedial actions were performed:

Landfill Consolidation and Grading – This step involved grading the existing landfill material within the established limits of LFE. Landfill material was excavated in areas of high elevation and recompacted in areas of low elevation relative to the excavation grading plan. The subsurface drainage pipe was abandoned in-place. Future surface water channel alignments were excavated to design grades and confirmation sampling along the edges of waste material that reached native ground was performed. Figure 2 shows the clean soil corridors and confirmation sampling locations. The coordinates of the confirmation sampling points are included in Table 2.

Landfill Gas (LFG) System Construction – This step involved placement of the LFG geocomposite layer over the landfill topdeck, excavation and backfilling of LFG trenches on the north face and topdeck, and excavation and backfilling in LFG vent-collector areas. In addition, geosynthetic material was placed above the LFG geocomposite along the western channel alignment .

Engineered Soil Cover Construction – This step involved placement and compaction of the clean soil cover over the landfill to meet the elevations shown on the final grading plan.

Final Construction Elements – In this final step, LFG vents were constructed and remaining surface water elements (channels, culverts, drop inlets, energy dissipation, etc.) installed. Vegetation and erosion control elements were installed as well.

August 2012 3 Landfill E Land Use Control

3.2 Residual Chemicals that Necessitate the LUC Table 1 below summarizes chemicals of concern (COCs) above cleanup levels remaining in soil at the LFE LUC Area.

TABLE 1 COCs REMAINING IN LANDFILL E LAND USE CONTROL AREA SOIL

Metals Organics

Antimony Arsenic Barium

Cadmium Copper Lead

Selenium Silver

Vanadium Zinc

4,4-DDE 4,4-DDT

Tetraethyl lead Benzo(a)anthracene

Benzo(a)pyrene Benzo(b)fluoranthene

Chrysene Fluoranthene

Indeno(1,2,3-cd)pyrene Naphthalene Phenanthrene

Pyrene

Table Notes: 1. Recreational and buffer zone ecological cleanup levels apply to the LFE LUC Area. However, residential

cleanup levels are applied to assess land use restrictions. The COCs listed in this table are those chemicals with concentrations in LFE LUC Area soil that exceed residential or ecological buffer zone cleanup levels.

2. Freshwater sediment cleanup levels also apply to existing surface water conveyances and areas where there are active seeps and springs.

In the Final FS/RAP, three COCs (cadmium, nickel, and total petroleum hydrocarbons as fuel oil [TPHfo]) were identified in groundwater beneath or near LFE at concentrations exceeding cleanup levels, but COC impacts to groundwater were considered minimal. The Final FS/RAP specifies that groundwater use at LFE will only be restricted if COC concentrations in groundwater are above drinking water levels (Geosyntec, 2011a). Based on the most recent groundwater monitoring results, concentrations of contaminants in groundwater at LFE are below drinking water levels. Therefore, no groundwater use restrictions are required for the LFE LUC Area. 4. SITE-SPECIFIC LAND USE RESTRICTIONS The following site-specific land use restrictions apply for soil at the LFE LUC Area:

The construction and operation of residences, schools, hospitals, and day care centers in the LFE LUC Area is prohibited without further remediation.

August 2012 4 Landfill E Land Use Control

Personnel potentially exposed to soils in the LFE LUC Area shall follow a site-specific Health and Safety Plan, have the appropriate level of health and safety training, and use the appropriate level of personal protective equipment specified in a Health and Safety Plan.

All soils excavated from the LFE LUC Area shall be managed and/or disposed in accordance with Presidio policies and procedures and applicable federal, state, and local laws and regulations.

Soil in the LFE LUC Area shall remain covered with a minimum of 2-feet of clean soil, concrete, asphalt, buildings, or another appropriate barrier.

5. INSPECTION, MAINTENANCE, AND REPAIR REQUIREMENTS The engineered soil cover in the LFE LUC Area will be inspected annually in accordance with the Operation and Maintenance Plan for Landfill E, Presidio of San Francisco, California (Geosyntec, 2012) and the results of the inspection and any repairs performed to the cover will be summarized in the annual Presidio Area B LUC Report. Pursuant to the Final FS/RAP (Geosyntec, 2011a), groundwater and surface water in the LFE area are being monitored quarterly in the initial one-year period following remediation in accordance with the Post-Remediation Groundwater and Surface Water Monitoring Plan for Landfill E, Presidio of San Francisco, California (Geosyntec, 2011b). The groundwater monitoring program is designed to verify the long-term effectiveness of the cover system in minimizing the potential for surface water infiltration and leaching of COCs from the landfill waste to groundwater. The surface water monitoring program is designed to verify surface water runoff does not come into contact with the landfill material and transport COCs offsite. At the conclusion of the first year, the cumulative data set will be reviewed and appropriate changes to the monitoring program, if any, will be proposed to DTSC for approval. LFG monitoring for LFE is being performed as described in the Post-Remediation Landfill Gas Monitoring Plan included in Appendix B of the CCR (Geosyntec, 2012a). The plan specifies that methane emissions from the 12 LFG vents and from the surface of the landfill topdeck be monitored quarterly during the first year following remediation. At the conclusion of the first year, the cumulative data set will be reviewed and appropriate changes to the monitoring program, if any, will be proposed to DTSC for approval. In accordance with the LUCMRR, valid values for the LFE LUC Area and survey coordinates are provided in Table 3.

Northing Easting

DAEEX101 477,215.72 1,434,529.04

DAEEX102 477,182.94 1,434,490.40

DAEEX103 477,177.93 1,434,447.20

DAEEX104 477,193.76 1,434,410.55

DAEEX105 477,215.77 1,434,361.50

DAEEX106 477,232.68 1,434,318.98

DAEEX107 477,246.71 1,434,270.16

DAEEX108 477,270.62 1,434,228.84

DAEEX109 477,315.98 1,434,213.38

DAEEX110 477,542.45 1,434,372.95

DAEEX111 477,579.80 1,434,403.52

DAEEX112 477,166.90 1,434,470.23

DAEEX113 477,177.48 1,434,426.12

DAEEX114 477,203.64 1,434,385.84

DAEEX115 477,222.03 1,434,340.29

DAEEX116 477,236.35 1,434,293.50

DAEEX117 477,256.57 1,434,248.25

DAEEX118 477,562.73 1,434,386.17

DAEEX119 477,601.09 1,434,415.68

Notes: (a) Field surveyed coordinates in California State Plane 1927, Zone III.

TABLE 2CONFIRMATION SAMPLING LOCATION COORDINATES

Landfill E, Presidio of San Francisco, California

Coordinates(a)

Sampling Point

August 2012 Landfill E Land Use Control 

Name Date File Name

(Valid Values) Northing 477,279.44

LFE_LUCAREA Sensitive Use Restrictions Easting 1,434,162.49 Landfill E LUC

Health and Safety Requirements Northing 477,532.87

Soil Management Requirements Easting 1,434,343.48

Surface Cover Restrictions Northing 477,757.46

Easting 1,434,522.74

Northing 477,793.33

Easting 1,434,800.85

Northing 477,690.17

Easting 1,434,843.90

Northing 477,590.24

Easting 1,434,818.65

Northing 477,450.12

Easting 1,434,678.08

Northing 477,108.96

Easting 1,434,489.08

Notes:

F

G

H

A

B

C

D

E

TABLE 3LANDFILL E AREA LAND USE CONTROLS

Presidio of San Francisco, California

Site Name Land Use ControlsLUCMRR Addendum Information

Coordinates(a)

August 2012 Landfill E Land Use Control 

August 2012 7 Landfill E Land Use Control

6. REFERENCES Geosyntec Consultants, Inc. (Geosyntec), 2011a. Final Feasibility Study/Remedial Action Plan

for Landfill E, Presidio of San Francisco, California. June. Geosyntec, 2011b. Post-Remediation Groundwater and Surface Water Monitoring Plan, Landfill E, Presidio of San Francisco, California. December. Geosyntec, 2012a. Construction Completion Report, Landfill E, Presidio of San Francisco,

California. August. Geosyntec, 2012b. Operation and Maintenance Plan, Landfill E, Presidio of San Francisco,

California. August. Presidio Trust, 2009. Presidio Trust Land Use Controls Master Reference Report, Presidio of

San Francisco, California. September.