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March AR# 569054 1 of 903

569054

MEMORANDUM FOR DISTRIBUTION 18 Dec 17

FROM: AFCEC/CZOW – March ARB 610 Meyer Drive, Bldg 2403 March ARB CA 92518

SUBJECT: Courtesy Copy of the Site Inspection Report, March Air Reserve Base, CA, Site Inspection of Aqueous Film Forming Foam (AFFF) Release Areas

1. Please find the Site Inspection of Aqueous Film Forming Foam (AFFF) Release Areas Report for March ARB for your information. The AFFF release areas were sampled according to the final Installation Specific Work Plan dated 14 April 2017.

2. The Federal Facility Agreement has primary and secondary documents starting at the

Remedial Investigation phase, this work plan is prior to the Remedial Investigation phase.

3. If you have any questions of comments, please contact me at (951) 655-5060

ERIC LEHTO

Remedial Project Manager

DISTRIBUTION:

Ms. Catherine Brown US EPA Region 9 75 Hawthorne Street San Francisco, CA 94105 brown.catherine@epa.gov

Mr. Stephen Niou Department of Toxic Substances Control 5796 Corporate Avenue Cypress, CA 90630 atephen.niou@dtsc.ca.gov

Ms. Patricia Hannon California Regional Water Quality Control Board, Santa Ana Region 3737 Main Street, Suite 500 Riverside CA 92501-3348 patricia.hannon@waterboards.ca.gov

Mr. Calvin C. Cox SpecPro Professional Services 18374 Phantom Street Victorville, CA 92394 Calvin.Cox@SpecProSvcs.com

March AR# 569054 2 of 903 mailto:patricia.hannon@waterboards.ca.gov mailto:Calvin.Cox@SpecProSvcs.com

Contract FA8903-16-D-0027 Task Order 0004

Prepared for:

Air Force Civil Engineer Center JBSA Lackland, Texas

December 2017

FINAL

SITE INSPECTION REPORT

MARCH AIR RESERVE BASE, CA

Site Inspection of Aqueous Film Forming

Foam (AFFF) Release Areas Environmental Programs Worldwide

March AR# 569054 3 of 903

FINAL

SITE INSPECTION REPORT

SITE INSPECTION OF AQUEOUS FILM FORMING FOAM (AFFF) RELEASE AREAS

ENVIRONMENTAL PROGRAMS WORLDWIDE

MARCH AIR RESERVE BASE, CALIFORNIA

Project No. RPMO20167118

Prepared for:

Air Force Civil Engineer Center

Joint Base San Antonio – Lackland, Texas

Prepared by:

Amec Foster Wheeler Programs, Inc.

Contract FA8903-16-D-0027 Task Order 0004

December 2017

March AR# 569054 4 of 903

Site Inspection of Aqueous Film Forming Foam (AFFF) Release Areas Final Site Inspection Report, March Air Reserve Base

Page iii

TABLE OF CONTENTS

ACRONYMS ...................................................................................................................................... vii

EXECUTIVE SUMMARY ...................................................................................................................... ix

1.0 INTRODUCTION

PER- AND POLY-FLUORINATED ALKYL SUBSTANCES OVERVIEW

PROJECT OBJECTIVES

PROJECT SCOPE

2.0 AFFF RELEASE AREA BACKGROUND

SITE LOCATION AND SETTING

SITE HISTORY

PREVIOUS INVESTIGATIONS

3.0 FIELD ACTIVITIES AND ANALYTICAL PROTOCOL

AFFF RELEASE AREA 1: PRE-2004 AFFF TRAILER SPILL

3.1.1 Sample Location and Methodologies

3.1.2 Analytical Results

3.1.3 Conclusions

AFFF RELEASE AREA 2: FORMER FIRE STATION

3.2.1 Sample Location and Methodologies

3.2.2 Analytical Results

3.2.3 Conclusions

AFFF RELEASE AREA 3: WATERSHED 2 OUTFALL

3.3.1 Sample Location and Methodologies

3.3.2 Analytical Results

3.3.3 Conclusions

AFFF RELEASE AREA 4: CURRENT FIRE STATION

3.4.1 Sample Location and Methodologies

3.4.2 Analytical Results

3.4.3 Conclusions

AFFF RELEASE AREA 5: NOZZLE SPRAY TEST AREA

3.5.1 Sample Location and Methodologies

3.5.2 Analytical Results

3.5.3 Conclusions

AFFF RELEASE AREA 6: IRP SITE 15 (FORMER FTA 3)

3.6.1 Sample Location and Methodologies

3.6.2 Analytical Results

3.6.3 Conclusions

AFFF RELEASE AREA 7: WATERSHED 1 OUTFALL

3.7.1 Sample Location and Methodologies

3.7.2 Analytical Results

3.7.3 Conclusions

March AR# 569054 5 of 903

Page iv

AFFF RELEASE AREA 8: 1985 NASA CONVAIR FIRE

3.8.1 Sample Location and Methodologies

3.8.2 Analytical Results

3.8.3 Conclusions

AFFF RELEASE AREA 9: 2010 AIRCRAFT BRAKE FIRE

3.9.1 Sample Location and Methodologies

3.9.2 Analytical Results

3.9.3 Conclusions

AFFF RELEASE AREA 10: 2004 AIRCRAFT BRAKE FIRE

3.10.1 Sample Location and Methodologies

3.10.2 Analytical Results

3.10.3 Conclusions

AFFF RELEASE AREA 11: 1989 F-4E CRASH

3.11.1 Sample Location and Methodologies

3.11.2 Analytical Results

3.11.3 Conclusions

4.0 MIGRATION/EXPOSURE PATHWAYS AND TARGETS

SOIL (SURFACE AND SUBSURFACE) EXPOSURE PATHWAY

4.1.1 Local Geologic Setting

4.1.2 Soil Exposure Pathways and Targets

4.1.3 Soil Exposure Conclusions

GROUNDWATER MIGRATION PATHWAY

4.2.1 Local Hydrogeologic Setting

4.2.2 Groundwater Exposure Pathways and Targets

4.2.3 Downgradient Drinking Water Supply Wells

4.2.4 Groundwater Exposure Conclusions

SEDIMENT EXPOSURE PATHWAY

4.3.1 Sediment Exposure Pathways and Targets

4.3.2 Sediment Exposure Conclusions

5.0 SUMMARY AND CONCLUSIONS

6.0 REFERENCES

March AR# 569054 6 of 903

Page v

FIGURES

Figure 2.1-1 Installation Location Map Figure 2.3-1 AFFF Release Areas Figure 3.0-2 Upper Alluvial Basewide Potentiometric Surface Map (Fourth Quarter 2016) Figure 3.0-3 Lower Alluvial Basewide Potentiometric Surface Map (Fourth Quarter 2016) Figure 3.0-4 Bedrock Basewide Potentiometric Surface Map (Fourth Quarter 2016) Figure 3.1-1 Sampling Locations and Groundwater Elevations, Pre-2004 AFFF Trailer Spill, AFFF Release

Area 1 Figure 3.1-2 PFAS in Groundwater, Pre-2004 AFFF Trailer Spill, AFFF Release Area 1 Figure 3.2-1 Sampling Locations and Groundwater Elevations, Former Fire Station, AFFF Release

Area 2 Figure 3.2-2 PFAS in Soil, Former Fire Station, AFFF Release Area 2 Figure 3.2-3 PFAS in Groundwater, Former Fire Station, AFFF Release Area 2 Figure 3.3-1 Sampling Locations, Watershed 2 Outfall, AFFF Release Area 3 Figure 3.3-2 PFAS in Sediment, Watershed 2 Outfall, AFFF Release Area 3 Figure 3.4-1 Sampling Locations and Groundwater Elevations, Current Fire Station, AFFF Release

Area 4 Figure 3.4-2 PFAS in Soil, Current Fire Station, AFFF Release Area 4 Figure 3.4-3 PFAS in Groundwater, Current Fire Station, AFFF Release Area 4 Figure 3.5-1 Sampling Locations and Groundwater Elevations, Nozzle Spray Test Area, AFFF Release

Area 5 Figure 3.5-2 PFAS in Soil, Nozzle Spray Test Area, AFFF Release Area 5 Figure 3.5-3 PFAS in Groundwater, Nozzle Spray Test Area, AFFF Release Area 5 Figure 3.6-1 Sampling Locations and Groundwater Elevations, IRP Site 15, AFFF Release Area 6 Figure 3.6-2 PFAS in Soil, IRP Site 15, AFFF Release Area 6 Figure 3.6-3 PFAS in Groundwater, IRP Site 15, AFFF Release Area 6 Figure 3.7-1 Sampling Locations, Watershed 1 Outfall, AFFF Release Area 7 Figure 3.7-2 PFAS in Sediment, Watershed 1 Outfall, AFFF Release Area 7 Figure 3.8-1 Sampling Locations, 1985 NASA Convair Fire, AFFF Release Area 8 Figure 3.8-2 PFAS in Soil, 1985 NASA Convair Fire, AFFF Release Area 8 Figure 3.8-3 PFAS in Groundwater, 1985 NASA Convair Fire, AFFF Release Area 8 Figure 3.9-1 Sampling Locations, 2010 Aircraft Brake Fire, AFFF Release Area 9 Figure 3.9-2 PFAS in Soil, 2010 Aircraft Brake Fire, AFFF Release Area 9 Figure 3.9-3 PFAS in Groundwater, 2010 Aircraft Brake Fire, AFFF Release Area 9 Figure 3.10-1 Sampling Locations, 2004 Aircraft Brake Fire, AFFF Release Area 10 Figure 3.10-2 PFAS in Soil, 2004 Aircraft Brake Fire, AFFF Release Area 10 Figure 3.10-3 PFAS in Groundwater, 2004 Aircraft Brake Fire, AFFF Release Area 10 Figure 3.11-1 Sampling Locations, 1989 F-4E Crash, AFFF Release Area 11

March AR# 569054 7 of 903

Page vi

Figure 3.11-2 PFAS in Soil, 1989 F-4E Crash, AFFF Release Area 11 Figure 3.11-3 PFAS in Groundwater, 1989 F-4E Crash, AFFF Release Area 11 Figure 4.2-1 Water Well Inventory

TABLES

Table 1.1-1 Regulatory Screening Values (Page 3 in Report) Table 3.0-1 Groundwater Elevations and Well Construction Details (Tables Section) Table 3.1-1 Summary of Soil Analytical Testing Results (Tables Section) Table 3.1-2 Summary of Soil General Chemistry Analytical Testing Results (Tables Section) Table 3.1-3 Summary of Groundwater Analytical Testing Results (Tables Section) Table 3.1-4 Summary of Sediment Analytical Testing Results (Tables Section) Table 4.0-1 Conceptual Site Model: Installation-Wide Summary (Tables Section) Table 5.0-1 Summary of Screening Level Exceedances (Page 38 in Report)

APPENDICES

Appendix A Photograph Logs Appendix B Field Forms

B-1 Field Activity Daily Logs B-2 Daily PFAS Protocol Checklists B-3 Tailgate Safety Meeting Reports B-4 Soil Boring/Monitoring Well Records B-5 Water Quality Sampling Instrument Calibration Forms B-6 Groundwater Sampling Records B-7 Sediment/Surface Water Sample Collection Logs

Appendix C Laboratory Analytical Reports (DVD) Appendix D Data Validation Reports Appendix E Bedrock Elevation Map and Geological Cross Section

March AR# 569054 8 of 903

Page vii

ACRONYMS

AECOM AECOM Technical Services, Inc.

AFB Air Force Base AFCEC Air Force Civil Engineer Center AFFF Aqueous Film Forming Foam AL lower alluvial unit Amec Foster Wheeler Amec Foster Wheeler Programs, Inc. and its affiliate Amec Foster

Wheeler Environment & Infrastructure Inc. (AEI) collectively ARB Air Reserve Base AU upper alluvial unit

BD bedrock unit bgs below ground surface BRAC Base Realignment and Closure

CDWR California Department of Water Resources CoC Chain-of-Custody

DL detection limit DoD Department of Defense DQO Data Quality Objective

EMWD Eastern Municipal Water District ft/day feet per day FTA fire training area FTS fluorotelomer sulfonate

HA Health Advisory HDPE high-density polyethylene HGL HydroGeoLogic, Inc.

HSA Hollow Stem Auger

IDW Investigation-Derived Waste IRP Installation Restoration Program ISWP Installation-Specific Work Plan

LC-MS/MS Liquid Chromatography and Tandem Mass Spectrometry μg/L micrograms per liter μg/kg micrograms per kilogram mg/kg milligrams per kilogram MS Matrix Spike MSD Matrix Spike Duplicate

March AR# 569054 9 of 903

Page viii

MWH MWH Americas, Inc.

NASA National Aeronautics and Space Administration NEtFOSAA N-Ethyl perfluorooctanesulfonamidoacetic acid (NEtFOSAA) NMeFOSAA N-Methyl perfluorooctanesulfonamidoacetic acid PA Preliminary Assessment PFAS per- and polyfluorinated alkyl substances PFBS perfluorobutanesulfonic acid PFDA Perfluorodecanoic acid PFDoA Perfluorododecanoic acid PFHpA perfluoroheptanoic acid PFHxA Perfluorohexanoic acid PFHxS perfluorohexanesulfonic acid PFNA perfluorononanoic acid PFOA perfluorooctanoic acid PFOS perfluorooctanesulfonic acid PFTA Perfluorotetradecanoic acid PFTrDA Perfluorotridecanoic acid PFUnA Perfluoroundecanoic acid pH potential of hydrogen PID photoionization detector PPE personal protective equipment PVC polyvinyl chloride

RSL Regional Screening Level

SI Site Investigation SIR Site Investigation Report SOP Standard Operating Procedure S.U. standard units

TOC total organic carbon

USAF United States Air Force USEPA United States Environmental Protection Agency

WMWD West Municipal Water District WS Watershed

March AR# 569054 10 of 903

Page ix

EXECUTIVE SUMMARY

This Site Inspection (SI) Report (SIR) was prepared by Amec Foster Wheeler Programs, Inc., together with our affiliate Amec Foster Wheeler Environment & Infrastructure, Inc., herein collectively referred to as Amec Foster Wheeler, under Contract No. FA8903-16-D-0027, Task Order 0004, to document the results of SI activities conducted at 11 aqueous film forming foam (AFFF) release areas located at March Air Reserve Base (ARB). The purpose of the SI was to determine, through environmental media sampling, if a release of per- and polyfluorinated alkyl substances (PFAS) has occurred at potential AFFF release areas identified by others during a Preliminary Assessment (PA) (HydroGeologic Inc. [HGL], 2015) and installation scoping visit conducted by Amec Foster Wheeler on 5 October 2016. The data presented in this SIR were collected and evaluated in accordance with the Final Installation-Specific Work Plan (ISWP) (Amec Foster Wheeler, 2017a) and the General Quality Program Plan (Amec Foster Wheeler, 2017b).

PFAS are a class of synthetic organofluorine compounds that possess a chemical structure that gives them unique properties, including thermal stability and the ability to repel both water and oil. These chemical properties make them useful components in a wide variety of consumer and industrial products, including non-stick cookware, food packaging, waterproof clothing, fabric stain protectors, lubricants, paints, and firefighting foams such as AFFF. AFFF concentrate contains fluorocarbon surfactants to meet required performance standards for fire extinguishing agents (Department of Defense [DoD] Military Specification MIL-F-24385F [SH], Amendment 1, 5 August 1994). The United States Air Force (USAF) began purchasing and using AFFF containing PFAS (perfluorooctanesulfonic acid [PFOS] and/or perfluorooctanoic acid [PFOA]) for extinguishing petroleum fires and during firefighting training activities in 1970. AFFF was primarily used on USAF installations at fire training areas (FTAs), but may have also been used, stored, or released from hangar fire suppression systems, at firefighting equipment testing and maintenance areas, and during emergency response actions for fuel spills and/or aircraft incidents.

The United States Environmental Protection Agency (USEPA) Office of Water issued lifetime drinking water Health Advisory (HA) values for PFOS and PFOA in May 2016 that replaced the 2009 Provisional HA values. The HA values for PFOS and PFOA are 0.07 micrograms per liter (μg/L) for each constituent;

however, when these two chemicals co-occur in a drinking water source, a conservative and health-protective approach is recommended that compares the sum of the concentrations (PFOS + PFOA) to the HA value (0.07 μg/L). HA values are not to be construed as legally enforceable federal standards and are subject to change as new information becomes available (USEPA, 2016a and 2016b). Although the USEPA has not established Regional Screening Levels (RSL) for PFOS and PFOA in soil, the USAF calculated a screening level of 1.26 milligrams per kilogram (mg/kg) for PFOS and PFOA in soil using the USEPA RSL calculator (https://epa-prgs.ornl.gov/cgi-bin/chemicals/csl_search).

While PFOS and PFOA are the focus of the HA and provide specific targets for the USAF to address in the SI, USEPA has also derived RSL values for perfluorobutanesulfonic acid (PFBS) for which there is a Tier 2 toxicity value (Provisional Peer Review Toxicity Value) (USEPA, 2017b). Concentrations of PFBS detected in groundwater and soil were compared to the RSLs of 400 μg/L and 1,300 mg/kg, respectively.

March AR# 569054 11 of 903

Page x

The USEPA has not issued HA values or promulgated standards for any other PFAS constituents to date.

March ARB is an active USAF installation located at approximately west longitude -117.256 by north latitude 33.896 at the northern end of the Perris Valley, east of the city of Riverside in Riverside County, California. The installation has been in operation since 1918 and formerly occupied approximately 7,123 acres.

Construction of March Air Force Base (AFB) began in late 1917 as a training installation at an existing airstrip named Alessandro Field, located approximately 12 miles southeast of the city of Riverside. In 1918, the first troops arrived at the training installation, making it home to the 818th Aero Squadron detachment. In 1921, activities were phased back due to reduced military budgets and March AFB was subsequently closed in 1923. March AFB was reopened in 1927 by the United States Army Air Corps as a training facility in accordance with their plan to expand pilot training and activate tactical units. The March AFB training facility became an active training facility in 1931 and at that time was recognized as an operational base. In these early years of operation, March was home to the 7th Bomb Group, the 17th Pursuit Group, and the 1st Bombardment Wing (USAF, 1994).

March AFB was selected for Base Realignment and Closure (BRAC) in 1993. In 1996, the approximately 2,700-acre cantonment area was retained for military use by the Air Force Reserve Command and was designated as March ARB. The remaining approximately 4,400 acres was closed as part of the nationwide BRAC, and re-designated as former March AFB.

The PA provided findings from research conducted to identify whether and where AFFF, containing PFAS, was stored, handled, used or released at March ARB. Based on the research conducted during the PA, as well as the information collected during an installation scoping visit conducted by Amec Foster Wheeler on 5 October 2016, the following 11 AFFF release areas were recommended for SI:

AFFF Release Area 1: Pre-2004 AFFF Trailer Spill

AFFF Release Area 2: Former Fire Station (Former Building 1223)

AFFF Release Area 3: Watershed 2 (WS-2) Outfall

AFFF Release Area 4: Current Fire Station (Building 1290)

AFFF Release Area 5: Nozzle Spray Test Area

AFFF Release Area 6: IRP Site 15 (Former FTA 3)

AFFF Release Area 7: Watershed 1 (WS-1) Outfall

AFFF Release Area 8: 1985 NASA Convair Fire

AFFF Release Area 9: 2010 Aircraft Brake Fire

AFFF Release Area 10: 2004 Aircraft Brake Fire

AFFF Release Area 11: 1989 F-4E Crash

March AR# 569054 12 of 903

Page xi

The specific objectives of the initial SI were as follows:

Determine if PFAS are present in soil, sediment, surface water, and/or groundwater at AFFF release areas selected for SI;

Determine if PFOS and PFOA concentrations in soil exceed the RSL of 1.26 mg/kg, and PFBS concentrations in soil exceed the RSL of 1,300 mg/kg;

Determine if concentrations of PFOS, PFOA, or the sum of PFOS and PFOA, in groundwater exceed the USEPA HA of 0.07 μg/L, and if PFBS concentrations in groundwater exceed the USEPA Tap Water RSL of 400 μg/L;

Determine if concentrations of PFOS or PFOA in sediment exceed the RSL of 1.26 mg/kg; and, Identify potential receptor pathways with immediate impacts to human health (immediate impact to human health is considered consumption of drinking water with PFOS/PFOA above the HA, or PFBS above the RSL).

PFAS Analytical Results

Review of analytical results indicated that PFAS are present in soil and groundwater at March ARB in excess of applicable USEPA HA value and/or RSLs. PFOS concentrations in soil exceeded the RSL at AFFF Release Areas 4 and 5. PFOS, PFOA, and/or PFOS+PFOA concentrations in groundwater exceeded the USEPA HA values at AFFF Release Areas 2, 4, 5, 6, 8, 9, 10, and 11. PFOS was detected in sediment at a concentration below the RSL at only one location, AFFF Release Area 7.

Potential human health exposure pathways were identified during this SI. Identified potential receptors and targets vary by AFFF release area and are summarized below.

Surface and Subsurface Soil Receptors

PFOS, PFOA, and/or PFBS were detected in soil at each of the AFFF release areas sampled; however, only PFOS exceeded the soil RSL at AFFF Release Areas 4 and 5.

Human receptors potentially exposed to PFAS in soil include on-site workers, specifically those involved with excavation or drilling activities, on-site residents, visitors, and trespassers.

Groundwater Receptors

PFOS and PFOA in groundwater exceeded the USEPA HA value of 0.07 μg/L for PFOS, PFOA, and/or the sum of PFOS/PFOA, at AFFF Release Areas 2, 4, 5, 6, 8, 9, 10, and 11.

Human receptors potentially exposed to PFAS in groundwater include persons on-base and off-base who are supplied drinking water by water supply wells downgradient of AFFF Release Areas. The primary sources of drinking water at March ARB are 1) surface water from Northern California through the State Water Project, 2) surface water from the Colorado River, and 3) groundwater supply wells. Groundwater wells supply approximately 25 percent of March AFB drinking water.

March AR# 569054 13 of 903

Page xii

There are two drinking water supply wells located downgradient of March ARB (Indian 59 and Perry 1).

Groundwater samples collected from these wells in June and October 2013 by Eastern Municipal Water District (EMWD) were analyzed for PFOS and PFOA. The maximum concentrations of PFOS and PFOA (0.082 μg/L and 0.052 μg/L, respectively) were detected in samples from the Indian 59 well (HGL, 2015 and EMWD, 2017). Indian 59, Perry 1, and two downgradient private water supply wells were also sampled and analyzed for PFAS in January 2016 by Amec Foster Wheeler. PFOA was detected in Perry 1 at a concentration of 0.0168 μg/L, below the USEPA HA value. PFOS and PFOS+PFOA were detected in Indian 59 at 0.108 μg/L and 0.1675 μg/L, respectively; above the USEPA HA value. The maximum concentrations of PFOS and PFOS+PFOA detected in the two residential wells were 0.0491 μg/L and 0.078 μg/L, respectively (Amec Foster Wheeler, 2016). Since PFAS were detected in drinking water supply wells, the groundwater exposure pathway is considered complete.

Sediment Receptors

PFOS was detected in sediment collected from AFFF Release Area 7 at a concentration below the RSL.

PFAS were not detected above laboratory reporting limits in sediment samples collected from AFFF Release Area 3.

Potential human receptors include on-site workers, visitors, and trespassers that may come in contact with sediment at or downstream of AFFF Release Area 7. However, the potential for exposure to PFAS in sediment is low because PFAS were only detected at low concentrations in one sample, in a location that is not routinely accessed by potential receptors.

March AR# 569054 14 of 903

1.0 INTRODUCTION

This Site Inspection (SI) Report (SIR) was prepared by Amec Foster Wheeler Programs, Inc., together with our affiliate Amec Foster Wheeler Environment & Infrastructure, Inc., herein collectively referred to as Amec Foster Wheeler, under Contract No. FA8903-16-D-0027, Task Order 0004, to document the results of SI activities conducted at 11 aqueous film forming foam (AFFF) release areas located at March Air Reserve Base (ARB). The purpose of the SI was to determine, through environmental media sampling, if a release of per- and polyfluorinated alkyl substances (PFAS) has occurred at potential AFFF release areas identified by others during a Preliminary Assessment (PA) (HydroGeologic Inc. [HGL], 2015) and during an installation scoping visit conducted by Amec Foster Wheeler on 5 October 2016.

The data presented in this SIR were collected and evaluated in accordance with the Final Installation- Specific Work Plan (ISWP) (Amec Foster Wheeler, 2017a) and the General Quality Program Plan (Amec Foster Wheeler, 2017c).

PER- AND POLY-FLUORINATED ALKYL SUBSTANCES OVERVIEW

PFAS are a class of synthetic organofluorine compounds that possess a chemical structure that gives them unique properties, including thermal stability and the ability to repel both water and oil. These chemical properties make them useful components in a wide variety of consumer and industrial products, including non-stick cookware, food packaging, waterproof clothing, fabric stain protectors, lubricants, paints, and firefighting foams such as AFFF. AFFF concentrate contains fluorocarbon surfactants to meet required performance standards for fire extinguishing agents (Department of Defense [DoD] Military Specification MIL-F-24385F [SH], Amendment 1, 5 August 1994). The United States Air Force (USAF) began purchasing and using AFFF containing PFAS (perfluorooctanesulfonic acid [PFOS] and/or perfluorooctanoic acid [PFOA]) for extinguishing petroleum fires and during firefighting training activities in 1970, as confirmed by the following federal government documents:

Military Specification for AFFF (MIL-F-24385), formally issued in 1969 (DoD, 1969);

General Accounting Office determination on sole source award protest to provide AFFF to the Navy in December 1969; and

A History of USAF Fire Protection Training at Chanute Air Force Base, 1964-1976 (Coates, 1977).

AFFF was primarily used on USAF installations at fire training areas (FTAs), but may have also been used, stored, or released from hangar fire suppression systems, at firefighting equipment testing and maintenance areas, and during emergency response actions for fuel spills and/or aircraft incidents.

The United States Environmental Protection Agency (USEPA) Office of Water issued lifetime drinking water Health Advisory (HA) values for PFOS and PFOA in May 2016 that replaced the 2009 Provisional HA values. The HA values for PFOS and PFOA are 0.07 micrograms per liter (μg/L) for each constituent;

however, when these two contaminants co-occur in a drinking water source, a conservative and health-protective approach is recommended that compares the sum of the concentrations (PFOS + PFOA) to the

March AR# 569054 15 of 903

HA value (0.07 μg/L). HA values are non-regulatory concentrations of drinking water contaminants at or below which adverse health effects are not anticipated to occur over specific exposure durations (e.g., 1 day, 10 days, and a lifetime). They serve as informal technical guidance to assist federal, state, and local officials, and managers of public or community water systems in protecting public health when emergency spills or other contamination situations occur. A HA document provides information on the environmental properties, health effects, analytical methodology, and treatment technologies for removing drinking water contaminants. HA values are not to be construed as legally enforceable federal standards and are subject to change as new information becomes available (USEPA, 2016a and 2016b).

The USEPA has not published Regional Screening Levels (RSLs) for PFOS or PFOA for soil or sediment;

however; for this project, a screening level of 1.26 milligrams per kilogram (mg/kg) for soil and sediment was calculated using the USEPA RSL calculator (https://epa-prgs.ornl.gov/cgi-bin/chemicals/csl_search).

The toxicity value input for the calculator is the Tier 3 value reference dose of 0.00002 mg/kg per day derived by the USEPA in their Drinking Water HA values for both PFOS and PFOA (USEPA, 2016a and 2016b).

While PFOS and PFOA are the focus of the HA and provide specific targets for the USAF to address in the SI, USEPA has also derived RSL values for perfluorobutanesulfonic acid (PFBS) for which there is a Tier 2 toxicity value (Provisional Peer Review Toxicity Value) (USEPA, 2017b). PFBS concentrations detected in groundwater and soil were compared to the RSLs of 400 μg/L and 1,300 mg/kg, respectively.

Table 1.1-1 below presents the screening values for comparing analytical results for PFOS, PFOA, and PFBS. The USEPA has not issued HA values or promulgated standards for any other PFAS to date.

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Table 1.1-1. Regulatory Screening Values.

Parameter Chemical Abstract Number

USEPA Regional Screening Level Table

(June 2017)a

Calculated RSL for Soils and Sedimentsb

(μg/kg)

USEPA Health Advisory for Drinking Water (Surface Water or Groundwater)c (μg/L)

Residential Soil (μg/kg)

Tap Water (μg/L)

PFOS 1763-23-1 NL NL 1,260

0.07d

PFOA 335-67-1 NL NL 1,260

PFBS 375-73-5 1.3E+6 400 NL NL

Notes:

a USEPA Regional Screening Levels (June 2017) [https://www.epa.gov/risk/regional-screening-levels-rsls-generic-tables-june-2017].

b Screening levels calculated using the USEPA Regional Screening Level calculator (https://epa-prgs.ornl.gov/cgi-bin/ chemicals/csl_search).

c USEPA, May 2016a. “Drinking Water Health Advisory for Perfluorooctane Sulfonate (PFOS)” and USEPA, May 2016b. “Drinking

Water Health Advisory for Perfluorooctanoic Acid (PFOA).”

d When both PFOA and PFOS are both present, the combined concentrations of PFOA and PFOS should be compared with the

0.07 μg/L health advisory level.

μg/kg - micrograms per kilogram PFOA - perfluorooctanoic acid μg/L - micrograms per liter PFOS - perfluorooctanesulfonic acid NL - not listed RSL - Regional Screening Level PFBS - perfluorobutanesulfonic acid USEPA - United States Environmental Protection Agency

PROJECT OBJECTIVES

In accordance with DoD Instruction 4715.18, “Emerging Contaminants (ECs)” (DoD, 2009), the Interim AF Guidance on Sampling and Response Actions for Perfluorinated Compounds at Active and Base Realignment and Closure (BRAC) Installations (USAF, 2012), and the SAF/IE Policy on Perfluorinated Compounds of Concern (USAF, 2016) the USAF will:

1) Identify locations where there is a reasonable expectation that there may have been a release of PFAS (defined below) associated with USAF actions;

2) Determine if there is unacceptable risk to human health and the environment; and

3) Address releases that pose an unacceptable risk, including offsite migration.

The primary objectives of this initial SI were to:

Determine if PFOS, PFOA, or PFBS are present in soil, groundwater, and/or sediment at AFFF release areas selected for SI;

Determine if PFOS and PFOA concentrations in soil exceed the RSL of 1.26 mg/kg, and if PFBS concentrations in soil exceed the RSL of 1,300 mg/kg;

Determine if PFOS, PFOA, or sum of PFOS and PFOA concentrations in groundwater exceed the USEPA HA value of 0.07 μg /L, and if PFBS concentrations in groundwater exceed the USEPA Tap Water RSL of 400 μg/L;

March AR# 569054 17 of 903

Determine if PFOS or PFOA concentrations in sediment exceed the RSL of 1.26 mg/kg; and, Identify potential receptor pathways with immediate impacts to human health (immediate impact to human health is considered consumption of drinking water with PFOS/PFOA above the HA, or PFBS above the RSL).

PROJECT SCOPE

Eleven AFFF release areas were selected for SI at March ARB based on research conducted by HGL (2015) during a PA and based on information gathered during an installation scoping visit conducted by Amec Foster Wheeler on 5 October 2016. The following 11 AFFF release areas recommended for SI are as follows:

AFFF Release Area 1: Pre-2004 AFFF Trailer Spill

AFFF Release Area 2: Former Fire Station (Former Building 1223)

AFFF Release Area 3: Watershed 2 (WS-2) Outfall

AFFF Release Area 4: Current Fire Station (Building 1290)

AFFF Release Area 5: Nozzle Spray Test Area

AFFF Release Area 6: IRP Site 15 (Former FTA 3)

AFFF Release Area 7: Watershed 1 (WS-1) Outfall

AFFF Release Area 8: 1985 NASA Convair Fire

AFFF Release Area 9: 2010 Aircraft Brake Fire

AFFF Release Area 10: 2004 Aircraft Brake Fire

AFFF Release Area 11: 1989 F-4E Crash

Media evaluated at each area included surface and subsurface (vadose zone) soil, groundwater, and/or sediment.

This SIR discusses and provides a comparison of analytical results to screening values for PFOS, PFOA, and PFBS in soil, groundwater, and sediment. The remaining PFAS do not have screening values; therefore, only the results of PFOS, PFOA, and PFBS are discussed in detail and presented in figures in this SIR.

However, data for all PFAS analyzed are presented in the soil, groundwater, and sediment analytical tables presented in this SIR.

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2.0 AFFF RELEASE AREA BACKGROUND

SITE LOCATION AND SETTING

March ARB is an active USAF installation located at approximately west longitude 117.256 by north latitude 33.896 at the northern end of the Perris Valley, east of the city of Riverside in Riverside County, California. The installation has been in operation since 1918 and formerly occupied approximately 7,123 acres (Amec Foster Wheeler, 2017a).

SITE HISTORY

Construction of March Air Force Base (AFB) began in late 1917 as a training installation at an existing airstrip named Alessandro Field, located approximately 12 miles southeast of the city of Riverside. In 1918, the first troops arrived at the training installation, making it home to the 818th Aero Squadron detachment. In 1921, activities were phased back due to reduced military budgets and March AFB was subsequently closed in 1923. March AFB was reopened in 1927 by the United States Army Air Corps as a training facility in accordance with their plan to expand pilot training and activate tactical units. The March AFB training facility became an active training facility in 1931 and at that time was recognized as an operational base. During the years of operation, March was home to the 7th Bomb Group, the 17th Pursuit Group, and the 1st Bombardment Wing (USAF, 1994).

March AFB was selected for Base Realignment and Closure (BRAC) in 1993. In 1996, the approximately 2,700-acre cantonment area was retained for military use by the Air Force Reserve Command and was designated as March ARB. The remaining approximately 4,400 acres was closed as part of the nationwide BRAC, and re-designated the former March AFB (Amec Foster Wheeler, 2017a).

PREVIOUS INVESTIGATIONS

HGL conducted a PA of FTA and non-FTA sites at March ARB to identify locations of where PFAS may have been used and released into the environment, and to provide an initial assessment of possible migration pathways and receptors of potential contamination (HGL, 2015). Twenty-three potential AFFF release areas were identified during the PA research. However, based on the PA research the following 10 potential AFFF areas recommended for SI as part of the PA (Figure 2.3-1):

Former Fire Station (Former Building 1223): Re-servicing of fire engines between 1956 and 2004/2005 caused an unknown amount of AFFF to be released when disconnecting hoses (minor drips observed), washing fire engines with AFFF residue, and on occasion during daily operational testing where AFFF was accidentally sprayed instead of water. Residual AFFF may have migrated to adjacent grassy/bare soil areas, remained on paved surfaces, or migrated with stormwater to nearby drainage channels during rain events.

Watershed 2 (WS-2) Outfall: Watershed 2 Outfall receives stormwater runoff from hangars and the northeast portion of the Base. Any AFFF released from the hangars or released into the environment, may have migrated with stormwater into storm drains that discharged to the WS-2

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Outfall. The potential for migration of surface contamination into nearby surface water is low because there are no permanent surface bodies near this outfall.

Current Fire Station (Building 1290): The re-servicing of fire engines since 2004 caused an unknown amount of AFFF to be released when disconnecting hoses (minor drips observed), washing fire engines with AFFF residue on trucks, and on occasion, during daily operational testing when AFFF was accidentally sprayed instead of water. Residual AFFF may have migrated to adjacent grassy/bare soil areas, remained on paved surfaces, or migrated with stormwater to nearby drainage channels during rain events.

Nozzle Spray Test Area: Each nozzle spray test resulted in the release of 25 gallons of AFFF and water onto the asphalt-paved road where the discharged AFFF was left in place and allowed to dissipate to adjacent grassy/dirt areas. Tests were performed annually for each fire engine and after major repairs to fire suppression systems. The total amount of AFFF discharged is unknown.

During rain events, AFFF could have migrated with stormwater to a nearby unlined drainage ditch.

Installation Restoration Program (IRP) Site 15 (Former FTA 3): The Former FTA was used from 1978 through the mid-1990’s, during which an unknown amount of AFFF was used during annual training exercises. Runoff from training activities was drained into a former unlined evaporation pond, the approximate location of which is the basis for the potential release area outline shown on Figure 2.1-1. Fire training activities occurred in the training pit east of the historical evaporation pond. In 1995, petroleum and polynuclear aromatic hydrocarbon-contaminated soil was excavated from both the training pit and the evaporation pond.

Watershed 1 (WS-1) Outfall: Watershed 1 outfall receives stormwater runoff from the aircraft ramp and a portion of the runway. An unknown amount of AFFF likely flowed into and through the WS-1 Outfall as the result of AFFF emergency response discharges and migration in stormwater. The potential for migration of surface contamination into nearby surface water is low because there are no permanent surface water bodies near this location.

1985 National Aeronautics and Space Administration (NASA) Convair Fire: A one-time event in which 1,915 gallons of AFFF were used to extinguish an aircraft fire on the runway. The AFFF applied likely migrated into the grassy areas and infiltrated into the subsurface near the crash location. During rain events, AFFF could have migrated with stormwater to a nearby drainage channel.

2010 Aircraft Brake Fire: A one-time event occurred in July 2010 when approximately 10 to 20 gallons of AFFF were used to extinguish a brake fire. The fire occurred approximately 1,300 feet from the north end of Runway 32. A small volume of AFFF may have infiltrated into the grassy/bare soil areas in the vicinity of the brake fire.

2004 Aircraft Brake Fire: A one-time event occurred in December 2004 when approximately 10 to 20 gallons of AFFF were used to extinguish a brake fire. The exact location of the fire is unknown; however, it was assumed to have occurred in the northern half of Runway 32. A small volume of AFFF may have infiltrated into the grassy/bare soil areas in the vicinity of the brake fire.

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1989 F-4E Crash: A one-time event occurred in July 1989 when an unknown amount of AFFF was potentially used to extinguish an aircraft fire. If used, a small volume of AFFF would have infiltrated into the ground in the vicinity of the crash in a grassy/bare soil field.

The following area is also recommended for investigation based on data obtained during the installation scoping visit conducted on 5 October 2016 (Figure 2.3-1):

Pre-2004 AFFF Trailer: Prior to 2004, the AFFF trailer was punctured by a forklift, resulting in a release of approximately 1,000 gallons of AFFF onto the paved area/road in the vicinity of the historical fire station. Although the AFFF was cleaned up, some residual AFFF likely remained in place. Residual AFFF may have migrated with stormwater to the WS-2 Outfall.

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3.0 FIELD ACTIVITIES AND ANALYTICAL PROTOCOL

Initial SI activities were conducted at March ARB from 22 May to 2 June 2017 at 11 AFFF release areas identified during the PA (HGL, 2015) and based on findings from the 5 October 2016 scoping visit (Figure 2.3-1). Sample locations were identified following discussions between Amec Foster Wheeler, March ARB, and Air Force Civil Engineer Center (AFCEC) personnel, and were documented in the Final ISWP (Amec Foster Wheeler, 2017a). Media sampled during the initial SI included surface soil, subsurface soil, sediment, and groundwater as described in the following sections.

Photographic documentation of the initial SI activities is provided in Appendix A and field documentation is provided in Appendix B. Initial SI activities were recorded by field personnel on field activity daily logs (Appendix B-1), and daily PFAS protocol checklists were completed to document that procedures were followed to prevent introduction of PFAS into field samples (Appendix B-2). A tailgate safety meeting was conducted each morning prior to beginning work; tailgate safety meeting reports are provided in Appendix B-3.

Soil Boring Advancement and Soil Sample Collection

Eighteen soil borings were advanced by California-licensed driller, J&H Drilling Co., Inc. of Buena Park, California to identify the presence or absence of PFAS in soil at eight of the 11 AFFF release areas at March ARB, as well as to characterize subsurface conditions. Soil borings were initially advanced to a depth of 5 feet below ground surface (bgs) with a hand auger and then advanced and sampled to planned depths using hollow-stem auger (HSA) drilling technology. Soil samples were continuously collected from the ground surface to first-encountered groundwater using 1) a hand auger (above 5 feet bgs) and 2) below 5 feet bgs using a decontaminated 18-inch-long split spoon sampler. The samples were field-screened for volatile organic vapors using a photoionization detector (PID) equipped with a 10.6 electron volt lamp.

The soil borings were logged by a qualified geoscientist in accordance with the Unified Soil Classification System. Drilling information, PID readings, lithologic logging observations, and soil sample depths and IDs are included on the soil boring records provided in Appendix B-4. Samples for laboratory analysis were collected at the ground surface by hand (nitrile glove covered) or by transferring samples from the split spoon sampler into laboratory-provided high-density polyethylene (HDPE) containers. Sample containers were sealed, labeled, packed into ice-filled coolers, and delivered under chain-of-custody (CoC) to SGS Accutest in Orlando, Florida. Soil samples were collected according to Standard Operating Procedure (SOP) AFW 02 – Soil Sampling. Soil sample locations are marked on the soil boring records provided in Appendix B-4.

Groundwater Elevations

Depth to water measurements were collected from soil borings and existing wells during the initial SI.

Elevations of the soil borings were not surveyed; therefore, groundwater elevation data was only calculated for existing wells. As part of the fourth quarter of 2016 basewide groundwater monitoring program, depth to water measurements were collected from existing monitoring wells by AECOM

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Technical Services, Inc. (AECOM). Water level measurements were reported in the Annual Monitoring Report (AECOM, 2017), and fourth quarter 2016 groundwater contours for the upper hydrostratigraphic alluvial unit, the lower hydrostratigraphic alluvial unit, and the bedrock hydrostratigraphic unit are depicted on Figures 3.0-2, 3.0-3 and 3.0-4. As shown on these figures, groundwater in each of the hydrostratigraphic units generally flows to the south-southeast. Depth to water measurements collected during the initial SI showed a water level increase from November 2016 to May 2017 of up to 3.5 feet in all measured wells with the exception of OU1GEW02, where water level depth decreased by approximately 2 feet. Groundwater elevations and well construction details for wells sampled during the initial SI are presented in Table 3.0-1.

Grab Groundwater Sampling

The initial SI groundwater sampling program included the collection of grab groundwater samples for laboratory chemical analysis of PFAS from 18 soil borings advanced using HSA technology. The target groundwater sample depths were selected based on field observations of first encountered groundwater, and each boring was advanced to 10 feet below the first encountered groundwater. Temporary 2-inch diameter polyvinyl chloride (PVC) casing with 10 feet of 0.01-inch slotted screen was installed in the boring through the HSA, and the auger was retracted 10 feet in order to expose the screen. Grab groundwater samples were collected from the PVC casing within each borehole using a peristaltic pump or stainless steel bailer.

Existing Well Sampling

The initial SI sampling program included collection of groundwater samples for laboratory chemical analysis of PFAS from eight existing wells. Samples were collected with a peristaltic pump using low-flow groundwater sampling methods. During low flow sampling, HDPE tubing was connected to a flow-through cell whereby groundwater pumped from the well was monitored for pH, temperature, specific conductivity, dissolved oxygen, and oxidation/reduction potential. Turbidity was measured with a separate turbidity meter. Groundwater sampling equipment was calibrated on a daily basis prior to use;

calibration data were recorded on water quality sampling instrument calibration forms presented in Appendix B-5. Depth to water was measured and field parameters were monitored until groundwater indicator parameters reached stabilization criteria in accordance with SOP AFW 03 – Groundwater Sampling. The flow-through cell was then removed and groundwater samples were collected directly into laboratory-provided HDPE containers from the discharge tubing. The sample containers were sealed, labeled, packed on ice in an insulated cooler, and delivered to SGS Accutest under CoC protocol.

Groundwater sampling activities were documented on groundwater sampling records provided in Appendix B-6.

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Soil Boring Abandonment

The PVC casings and screens that were used to collect groundwater from the 18 soil borings were removed and disposed of in a dumpster at the installation. The 18 boreholes were abandoned by the end of each day with grout and bentonite chips in accordance with SOP AFW 06 – Borehole Abandonment.

Sediment Sampling

Sediment samples were collected during the initial SI to assess the presence or absence of PFAS in sediment at surface drainage outfalls associated with AFFF Release Area 3 (Watershed 2 Outfall which discharges into the unlined Heacock Channel) and AFFF Release Area 7 (Watershed 1 Outfall which discharges into the Perris Storm Drain, Lateral A). Samples were collected by hand from two depths— surface and near surface—in accordance with SOP AFW 07 – Sediment Sampling, and placed into laboratory-provided containers. The sample containers were sealed, labeled, packed on ice in an insulated cooler, and delivered to SGS Accutest under CoC protocol. Sample collection data was documented on sediment/surface soil/surface water sample collection logs provided in Appendix B-7.

Total Sample Counts

The following provides a summary of samples (including field duplicate samples) collected by media during initial SI activities at March ARB:

40 soil samples (including four duplicate samples) were collected at 18 soil boring locations;

29 groundwater samples (including three duplicate samples) were collected from 18 soil borings and eight existing permanent monitoring wells; and

Five sediment samples (including one duplicate sample) were collected at two AFFF release areas.

Samples collected during the initial SI were analyzed for the following 16 PFAS compounds:

PFOS;

PFOA;

PFBS;

Perfluoroheptanoic acid (PFHpA);

Perfluorohexanesulfonic acid (PFHxS);

Perfluorononanoic acid (PFNA);

N-Ethyl perfluorooctanesulfonamidoacetic acid (NEtFOSAA);

N-Methyl perfluorooctanesulfonamidoacetic acid (NMeFOSAA);

Perfluorodecanoic acid (PFDA);

Perfluorotetradecanoic acid (PFTA);

Perfluorododecanoic acid (PFDoA);

Perfluorohexanoic acid (PFHxA);

Perfluorotridecanoic acid (PFTrDA);

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Perfluoroundecanoic acid (PFUnA);

6:2 fluorotelomer sulfonate (FTS); and

8:2 FTS.

Soil, groundwater, sediment, and surface water samples were analyzed by SGS Accutest in Orlando, Florida, a DoD Environmental Laboratory Accreditation Program accredited certified laboratory. Samples were analyzed by Modified USEPA Method 537 using Liquid Chromatography and Tandem Mass Spectrometry (LC-MS/MS). The LC-MS/MS method provides acceptable detection limits to confirm the presence of PFAS listed above. The laboratory analytical reports for the PFAS samples collected during the SI are included in Appendix C.

Analytical results for PFOS, PFOA, and PFBS are discussed in the following sections, while the analytical results for the remaining PFAS constituents are provided in tables at the conclusion of this SIR.

Co-occurrence of PFOS and PFOA (PFOS + PFOA) in aqueous samples was reported using the following guidelines:

1. If PFOS and PFOA are both detected at concentrations at or above the laboratory detection limit (DL) in groundwater and/or surface water used for drinking water, then the reported concentration for PFOA was added to the reported concentration for PFOS.

2. If only PFOS or only PFOA is detected at or above the DL in groundwater, then the concentration of the detected analyte only is reported.

3. If neither PFOA nor PFOS are detected at concentrations at or above the DL, then co-occurrence was reported as Not Detected.

One composite surface soil sample and one composite subsurface soil sample were also collected at each AFFF release area where soil sampling was conducted and submitted to CT Laboratories in Baraboo, Wisconsin for laboratory analysis of physiochemical properties, including soil pH (USEPA Method 9045B), particle size analysis (ASTM International D422), and total organic carbon (TOC) content (USEPA 9060 or Lloyd Kahn Method). The particle size analysis was subcontracted to Mi-Tech Services, Inc. in Weston, Wisconsin. The laboratory analytical reports for the physiochemical properties samples collected during the SI are included in Appendix C.

Data Validation and Usability Assessment

The quality and usability of data obtained during the project was determined by reviewing and inspecting field logbooks, sampling forms, chain of custody forms, laboratory data packages, and data validation reports; and verifying that the sampling procedures and analytical results were obtained following the applicable protocols such that they will satisfy project requirements and can be relied upon for evaluating the data with respect to project data quality objectives (DQOs). The data usability assessment identifies possible effects on data usage resulting from project requirement failures (i.e., data quality), and the adequacy of the data in meeting project-specific quality assurance/quality control requirements (i.e., data usability).

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The main project DQO is the determination of the presence (concentrations greater than the laboratories’ DLs, defined as the smallest analyte concentration that can be demonstrated to be different from zero or a blank concentration at the 99% level of confidence) or absence of PFAS in sampled media from identified AFFF areas.

Amec Foster Wheeler validated data from soil, sediment, and groundwater samples that were collected between 8 May and 2 June 2017 and analyzed for PFAS by modified USEPA Method 537. A description of the data validation scope, data validation procedures, and data validation observations and actions is presented in the data validation reports in Appendix D.

Amec Foster Wheeler performed USEPA Stage 4 data validation on 10% of the samples for each media, and USEPA stage 2B on the remaining samples.