FINAL 

Site Inspection Report 

Army Aviation Support Facility #1 

Williamstown, West Virginia 

Site Inspections for Perfluorooctanoic Acid (PFOA), Perfluorooctanesulfonic Acid (PFOS), 

Perfluorohexanesulfonic Acid (PFHxS), Perfluorononanoic Acid (PFNA), Hexafluoropropylene 

oxide dimer Acid (HFPO-DA) and Perfluorobutanesulfonic Acid (PFBS) 

ARNG Installations, Nationwide

September 2023

Prepared for: 

Army National Guard Headquarters 

111 S. George Mason Drive 

Arlington, VA 22204 

UNCLASSIFIED
Site Inspection Report 

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TABLE OF CONTENTS 

Page 

LIST OF APPENDICES ................................................................................................................ iv

LIST OF FIGURES ........................................................................................................................ v

LIST OF TABLES ......................................................................................................................... vi

LIST OF ACRONYMS AND ABBREVIATIONS ....................................................................... 1

EXECUTIVE SUMMARY ...................................................................................................... ES-1

1. INTRODUCTION ............................................................................................... 1-1

1.1 PROJECT AUTHORIZATION ............................................................... 1-1

1.2 SITE INSPECTION PURPOSE .............................................................. 1-1

2. FACILITY BACKGROUND .............................................................................. 2-1

2.1 FACILITY LOCATION AND DESCRIPTION ..................................... 2-1

2.2 FACILITY ENVIRONMENTAL SETTING .......................................... 2-1

2.2.1 Geology ..................................................................................... 2-1

2.2.2 Hydrogeology ........................................................................... 2-2

2.2.3 Hydrology ................................................................................. 2-3

2.2.4 Climate ...................................................................................... 2-3

2.2.5 Current and Future Land Use .................................................... 2-3

2.2.6 Sensitive Habitat and Threatened/Endangered Species ............ 2-3

2.3 HISTORY OF PFAS USE ....................................................................... 2-4

3. SUMMARY OF AREAS OF INTEREST ........................................................... 3-1

3.1 AOI 1 – BURN PIT FTA ......................................................................... 3-1

3.2 AOI 2 – WASH PAD ............................................................................... 3-1

3.3 AOI 3 – AFFF STORAGE ...................................................................... 3-2

3.4 ADJACENT SOURCES .......................................................................... 3-2

4. PROJECT DATA QUALITY OBJECTIVES ..................................................... 4-1

4.1 PROBLEM STATEMENT ...................................................................... 4-1

4.2 INFORMATION INPUTS ....................................................................... 4-1

4.3 STUDY BOUNDARIES ......................................................................... 4-1

4.4 ANALYTICAL APPROACH ................................................................. 4-1

4.5 DATA USABILITY ASSESSMENT ...................................................... 4-2

5. SITE INSPECTION ACTIVITIES ...................................................................... 5-1
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5.1 PRE-INVESTIGATION ACTIVITIES ................................................... 5-1

5.1.1 Technical Project Planning ....................................................... 5-2

5.1.2 Utility Clearance ....................................................................... 5-2

5.1.3 Source Water and PFAS Sampling Equipment Acceptability .. 5-2

5.2 HAND AUGUR SOIL SAMPLING ....................................................... 5-3

5.3 SOIL BORINGS AND SOIL SAMPLING ............................................. 5-3

5.4 TEMPORARY WELL INSTALLATION AND GROUNDWATER 

GRAB SAMPLING ................................................................................. 5-4

5.5 SYNOPTIC WATER LEVEL MEASUREMENTS ............................... 5-4

5.6 SURVEYING .......................................................................................... 5-4

5.7 INVESTIGATION-DERIVED WASTE ................................................. 5-4

5.8 LABORATORY ANALYTICAL METHODS ....................................... 5-5

5.9 DEVIATIONS FROM SITE INVESTIGATION UFP-QAPP 

ADDENDUM .......................................................................................... 5-5

6. SITE INSPECTION RESULTS .......................................................................... 6-1

6.1 SCREENING LEVELS ........................................................................... 6-1

6.2 SOIL PHYSICOCHEMICAL ANALYSES ............................................ 6-2

6.3 AOI 1 ....................................................................................................... 6-2

6.3.1 AOI 1 – Soil Analytical Results................................................ 6-2

6.3.2 AOI 1 – Groundwater Analytical Results ................................. 6-3

6.3.3 AOI 1 – Conclusions ................................................................. 6-3

6.4 AOI 2 ....................................................................................................... 6-3

6.4.1 AOI 2 – Soil Analytical Results................................................ 6-3

6.4.2 AOI 2 – Groundwater Analytical Results ................................. 6-4

6.4.3 AOI 2 – Conclusions ................................................................. 6-4

6.5 AOI 3 ....................................................................................................... 6-4

6.5.1 AOI 3 – Soil Analytical Results................................................ 6-4

6.5.2 AOI 3 – Groundwater Analytical Results ................................. 6-4

6.5.3 AOI 3 – Conclusions ................................................................. 6-5

6.6 Facility boundary ..................................................................................... 6-5

6.6.1 Soil Analytical Results .............................................................. 6-5

6.6.2 Groundwater Analytical Results ............................................... 6-5

7. EXPOSURE PATHWAYS .................................................................................. 7-1

7.1 SOIL EXPOSURE PATHWAY .............................................................. 7-1
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7.1.1 AOI 1 ........................................................................................ 7-2

7.1.2 AOI 2 ........................................................................................ 7-2

7.1.3 AOI 3 ........................................................................................ 7-3

7.2 GROUNDWATER EXPOSURE PATHWAY........................................ 7-3

7.3 SURFACE WATER AND SEDIMENT EXPOSURE PATHWAY ....... 7-3

8. SUMMARY AND OUTCOME .......................................................................... 8-1

8.1 SITE INSPECTION ACTIVITIES .......................................................... 8-1

8.2 OUTCOME .............................................................................................. 8-1

9. REFERENCES .................................................................................................... 9-1
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LIST OF APPENDICES 

Appendix A. Data Usability Assessment and Data Validation Reports 

Appendix B. Field Documentation 

B1. Logs of Daily Notice of Field Activities 

B2. Sampling Forms 

B3. Survey Data 

B4. Field Request Change Forms 

Appendix C. Photographic Log 

Appendix D. Technical Project Planning Meeting Minutes 

Appendix E. Boring Logs and Well Construction Diagrams 

Appendix F. Analytical Results 

Appendix G. Laboratory Reports
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LIST OF FIGURES 

Figure 2-1. Facility Location 

Figure 2-2. Topography 

Figure 2-3. Groundwater Features 

Figure 2-4. Surface Water Features 

Figure 3-1. Areas of Interest 

Figure 5-1. Site Inspection Sample Locations 

Figure 6-1. PFOS Detections in Soil (AOI 1) 

Figure 6-2. PFOA Detections in Soil (AOI 1) 

Figure 6-3. PFBS Detections in Soil (AOI 1) 

Figure 6-4. PFHxS Detections in Soil (AOI 1) 

Figure 6-5. PFNA Detections in Soil (AOI 1) 

Figure 6-6. PFOS Detections in Soil (AOIs 2 and 3) 

Figure 6-7. PFOA Detections in Soil (AOIs 2 and 3) 

Figure 6-8. PFBS Detections in Soil (AOIs 2 and 3) 

Figure 6-9. PFHxS Detections in Soil (AOIs 2 and 3) 

Figure 6-10. PFNA Detections in Soil (AOIs 2 and 3) 

Figure 7-1. Conceptual Site Model (AOI 1) 

Figure 7-2. Conceptual Site Model (AOI 2) 

Figure 7-3. Conceptual Site Model (AOI 3) 
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LIST OF TABLES 

Table ES-1. Screening Levels (Soil and Groundwater) 

Table ES-2. Summary of Site Inspection Findings and Recommendations 

Table 5-1. Samples by Medium, AASF #1, Williamstown, West Virginia, Site Inspection 

Report 

Table 5-2. Soil Boring Depths and Temporary Well Screen Intervals, AASF #1, 

Williamstown, West Virginia, Site Inspection Report 

Table 6-1. Screening Levels (Soil and Groundwater) 

Table 6-2. PFOA, PFOS, PFBS, PFNA, and PFHxS Results in Surface Soil, Site 

Inspection Report, AASF #1, Williamstown, West Virginia

Table 6-3. PFOA, PFOS, PFBS, PFNA, and PFHxS Results in Shallow Subsurface Soil, 

Site Inspection Report, AASF #1, Williamstown, West Virginia

Table 6-4. PFOA, PFOS, PFBS, PFNA, and PFHxS Results in Deep Subsurface Soil, Site 

Inspection Report, AASF #1, Williamstown, West Virginia

Table 8-1. Summary of Site Inspection Findings and Recommendations 
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LIST OF ACRONYMS AND ABBREVIATIONS 

% Percent

°C Degrees Celsius

oF Degrees Fahrenheit

μg/kg Microgram(s) per kilogram 

μg/L Microgram(s) per liter

AASF Army Aviation Support Facility 

AECOM AECOM Technical Services, Inc. 

AFFF Aqueous film forming foam 

amsl Above mean sea level 

AOI Area of interest 

ARNG Army National Guard 

ASTM ASTM International

bgs Below ground surface 

btoc Below top of casing 

CERCLA Comprehensive Environmental Response, Compensation, and Liability Act 

CSM Conceptual site model 

DoD Department of Defense

DQO Data quality objective 

DUA Data Usability Assessment 

EA EA Engineering, Science, and Technology, Inc., PBC 

EB Equipment blank

ELAP Environmental Laboratory Accreditation Program 

EM Engineer Manual

ft Foot (feet) 

FTA Fire Training Area 

HFPO-DA Hexafluoropropylene oxide dimer acid 

ID Identification 

IDW Investigation-derived waste

in. Inch(es)

ITRC Interstate Technology Regulatory Council 

LC/MS/MS Liquid chromatography tandem mass spectrometry 

LQU Large Quantity User 

mg/kg Microgram(s) per kilogram 

MIL-SPEC Military specification 
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LIST OF ACRONYMS AND ABBREVIATIONS (continued)

MS Matrix spike 

MSD Matrix spike duplicate 

NFA No further action

ng/L Nanogram(s) per liter 

No. Number

OSD Office of the Secretary of Defense

PA Preliminary Assessment 

PFAS Per- and polyfluoroalkyl substances 

PFBS Perfluorobutanesulfonic acid

PFHxS Perfluorohexanesulfonic acid

PFNA Perfluorononanoic acid 

PFOA Perfluorooctanoic acid

PFOS Perfluorooctanesulfonic acid

PID Photoionization detector

QAPP Quality Assurance Project Plan 

QSM Quality Systems Manual 

RI Remedial investigation

SI Site inspection

SL Screening level

TOC Total organic carbon 

TPP Technical Project Planning 

UFP Uniform Federal Policy 

USACE U.S. Army Corps of Engineers 

USCS Unified Soil Classification System 

USEPA U.S. Environmental Protection Agency 

USGS U.S. Geological Survey 

WVARNG West Virginia Army National Guard 

WAASF #1 Williamstown Army Aviation Support Facility #1 

WHAASF #2 Wheeling Army Aviation Support Facility #2
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EXECUTIVE SUMMARY 

The Army National Guard (ARNG) G-9 is performing Preliminary Assessments (PAs) and 

Site Inspections (SIs) at ARNG facilities nationwide based on the current or potential 

historical use of per- and polyfluoroalkyl substances (PFAS) with a focus on the six compounds 

presented in the memorandum from the Office of the Secretary of Defense (OSD) (Assistant 

Secretary of Defense) dated 6 July 2022. The six compounds listed in the OSD memorandum 

include perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA), and 

perfluorobutanesulfonic acid (PFBS), perfluorononanoic acid (PFNA), perfluorohexanesulfonic 

acid (PFHxS), and hexafluoropropylene oxide dimer acid (HFPO-DA).1 These compounds are 

collectively referred to as “relevant compounds” throughout the document and the applicable 

screening levels (SLs) are provided in Table ES-1. 

The PA identified three Areas of Interest (AOIs) where PFAS-containing materials may have 

been stored, disposed, or released historically (see Table ES-2 for AOI listing). The objective of 

the SI is to identify whether there has been a release to the environment from the AOIs identified 

in the PA and determine whether further investigation is warranted, a removal action is required 

to address immediate threats, or no further action is required based on a comparison of SI results 

to SLs for the relevant compounds. This SI was completed at the Williamstown Army Aviation 

Support Facility (AASF) #1 in Williamstown, West Virginia, and determined further evaluation 

under the Comprehensive Environmental Response, Compensation, and Liability Act 

(CERCLA) is warranted for AOI 2. Williamstown AASF is also referred to as the “Facility” 

throughout this document. 

Williamstown AASF #1, operated by the West Virginia ARNG (WVARNG), encompasses 

approximately 102.8 acres in Williamstown, West Virginia, within Wood County. The Facility is 

located adjacent to the Mid-Ohio Valley Regional Airport, west of Runway 21, and is utilized 

as an operational military facility, providing training and support for an active WVARNG 

unit since the completion of the Facility in 1992. The Facility is located in the Appalachian 

Plateau Physiographic Province, characterized by steep hillslopes and ravines formed through 

post-glacial erosional processes. The Ohio River can be found between 2.5 to 3.5 miles to the 

north, east, and west of the Facility (AECOM Technical Services, Inc. 2020). 

The PA identified three AOIs for investigation during the SI phase. SI sampling results from the 

AOIs were compared to OSD SLs. Table ES-2 summarizes the SI results for the AOIs. Based on 

the results of this SI, further evaluation under CERCLA is warranted in a remedial investigation 

(RI) for AOI 2. 

1

 Of the six PFAS compounds presented in the 6 July 2022 OSD memorandum, HFPO-DA (commonly referred to as 

GenX) was not included as an analyte at the time of this SI. Based on the conceptual site model (CSM) developed 

during the PA and revised based on SI findings, the presence of HFPO-DA is not anticipated at the Facility because 

HFPO-DA is generally not a component of military specification (MIL-SPEC) aqueous film forming foam (AFFF) 

and based on its history including distribution limitations that restricted use of GenX, it is generally not a component 

of other products the military used. In addition, it is unlikely that GenX would be an individual chemical of concern 

in the absence of other PFAS.
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Table ES-1. Screening Levels (Soil and Groundwater) 

Analyte2

Residential 

(Soil) 

(μg/kg)1 

0 to 2 ft bgs 

Industrial/Commercial 

Composite Worker 

(Soil) 

(μg/kg) 1 

2 to 15 ft bgs 

Tap Water 

(Groundwater) 

(ng/L) 1 

PFOA 19 250 6

PFOS 13 160 4

PFBS 1,900 25,000 601

PFHxS 130 1,600 39

PFNA 19 250 6

Notes: 

1. Assistant Secretary of Defense. 2022. Risk-Based SLs in Groundwater and Soil using U.S.

Environmental Protection Agency’s Regional SL Calculator. Hazard Quotient=0.1. May 2022.

2. Of the six PFAS compounds presented in the 6 July 2022 OSD memorandum, HFPO-DA

(commonly referred to as GenX) was not included as an analyte at the time of this SI. Based

on the CSM developed during the PA and revised based on SI findings, the presence of

HFPO-DA is not anticipated at the facility because HFPO-DA is generally not a component of

MIL-SPEC AFFF and based on its history including distribution limitations that restricted use

of GenX, it is generally not a component of other products the military used. In addition, it is

unlikely that GenX would be an individual chemical of concern in the absence of other PFAS.

g/kg = Microgram(s) per kilogram 

ng/L = Nanogram(s) per liter 

ft = feet 

bgs = below ground surface 

Table ES-2. Summary of Site Inspection Findings and Recommendations 

AOI 

Potential Release 

Area

Soil 

Source Area

Groundwater 

Source Area

Groundwater 

Facility Boundary Future Action 

1 Burn Pit FTA NA NA NFA 

2 Wash Pad FTA NA NA Proceed to RI 

3 AFFF Storage NA NA NFA 

 Legend: 

 = Detected; exceedance of SLs 

 = Detected; no exceedance of SLs 

 = Not detected 

 FTA = Fire Training Area 

 NA = Not applicable; no temporary wells were installed at any AOI, or boundary location and no groundwater 

samples were collected or analyzed. 

NFA = No further action 
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1. INTRODUCTION

1.1 PROJECT AUTHORIZATION 

The Army National Guard (ARNG) G-9 is the lead agency in performing Preliminary 

Assessments (PAs) and Site Inspections (SIs) at ARNG facilities nationwide based on the current 

or potential historical use of per- and polyfluoroalkyl substances (PFAS) with a focus on six 

compounds presented in the memorandum from the Office of the Secretary of Defense (OSD) 

dated 6 July 2022 (Assistant Secretary of Defense 2022). The six compounds listed in the OSD 

memorandum will be referred to as “relevant compounds” throughout this document and include 

perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorobutanesulfonic 

acid (PFBS), perfluorononanoic acid (PFNA), perfluorohexanesulfonic acid (PFHxS), and 

hexafluoropropylene oxide-dimer acid (HFPO-DA)2 at ARNG facilities nationwide. The ARNG 

performed this SI at Williamstown AASF #1 in Williamstown, West Virginia. Williamstown 

AASF #1 is also referred to as the “Facility” throughout this report. 

The SI project elements were performed in compliance with Comprehensive Environmental 

Response, Compensation, and Liability Act (CERCLA) (U.S. Environmental Protection Agency 

[USEPA] 1980), as amended, the National Oil and Hazardous Substances Pollution Contingency 

Plan (40 Code of Federal Regulations Part 300) (USEPA 1994), and in compliance with Army 

requirements and guidance for field investigations. 

1.2 SITE INSPECTION PURPOSE 

A PA was performed at Williamstown AASF #1 (AECOM Technical Services, Inc. [AECOM] 

2020) that identified three Areas of Interest (AOIs) where PFAS-containing materials were used, 

stored, disposed, or released historically. The objective of the SI is to identify whether there has 

been a release to the environment from the AOIs identified in the PA and determine whether 

further investigation is warranted, a removal action is required to address immediate threats, or 

no further action (NFA) is required based on screening levels (SLs) for the relevant compounds.

2

 Of the six PFAS compounds presented in the 6 July 2022 OSD memorandum, HFPO-DA (commonly referred to as 

GenX) was not included as an analyte at the time of this SI. Based on the conceptual site model (CSM) developed 

during the PA and revised based on SI findings, the presence of HFPO-DA is not anticipated at the facility because 

HFPO-DA is generally not a component of military specification (MIL-SPEC) aqueous film forming foam (AFFF) 

and based on its history including distribution limitations that restricted use of GenX, it is generally not a component 

of other products the military used. In addition, it is unlikely that GenX would be an individual chemical of concern 

in the absence of other PFAS.
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2. FACILITY BACKGROUND

2.1 FACILITY LOCATION AND DESCRIPTION 

AASF #1 occupies 102.8 acres in Williamstown, West Virginia (Figure 2-1). The Facility is 

located adjacent to the Mid-Ohio Valley Regional Airport, west of Runway 21. Land to the south 

and east of the Facility is a combination of residential and forested, while land to the north and 

west is primarily forested and agricultural. The nearest suburban area is Parkersburg, West 

Virginia, and is located 7.8 miles southwest of the Facility (AECOM 2020). 

The AASF is located on a portion of land the West Virginia National Guard leased from the 

Wood County Airport Authority for a term of 50 years starting in August 1986. On 1 July 2022, 

a new lease agreement with Wood County Airport Authority was entered for a period of five 

years, up for renewal on 27 June 2027. AASF #1 has operated as a military facility since 

construction was completed around 1992 when the unit moved from their previous location on 

the opposite side of the airport to the southeast (AECOM 2020). 

2.2 FACILITY ENVIRONMENTAL SETTING 

Williamstown AASF #1 is located in Wood County, West Virginia, directly south of the 

residential area of Williamstown, and northeast of Parkersburg, West Virginia. The Facility is 

approximately 627 feet (ft) above mean sea level (amsl) (Figure 2-2). This area of West Virginia 

is located in the Appalachian Plateau Physiographic Province. Typical surface features in the 

surrounding area include steep hillslopes and ravines formed through erosional processes. AASF 

#1 sits at the top of a plateau, with forested land in its immediate surroundings. AASF #1 is 

within the Middle Ohio South Watershed, the tributaries of which feed the major geographic 

feature in this area, the Ohio River, which is found between 2.5 to 3.5 miles from the Facility to 

the east, north, and west (AECOM 2020). 

The following sections include information on geology, hydrogeology, hydrology, climate, and 

current and future land use. The regional geology and groundwater features are shown on Figure 

2-3. The regional surface water features and drainage basins are shown on Figure 2-4.

2.2.1 Geology 

The exposed geologic group in the Williamstown area is the Upper Pennsylvanian or Permian 

Dunkard group, which consists of shale, sandstone, limestone, and coal. Underlying is the Lower 

Pennsylvanian group, also comprised of shale, sandstone, limestone, coal, and a sandstone 

conglomerate in the older section of the stratum. Below this group is the Mississippian group, 

consisting of undivided sedimentary rocks, siltstone, shale, sandstone, Pleistocene age glacial 

deposits, and Maxville Limestone. Soils in this area are composed of shale, sandstone, limestone, 

and coal, the same rocks that make up the underlying Pennsylvanian or Permian Dunkard group 

(AECOM 2020). 

Soils primarily composed of silts and medium to fine grained sands with varying amounts of clay 

and gravel were the dominant lithology encountered during the SI field events. Boring 

completion depths ranged between 5 to 44 ft below ground surface (bgs). Grain size analysis was 
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performed on samples AOI01-03, AOI02-02, AOI03-02, and boundary sample WAASF-03 and 

analyzed via ASTM International (ASTM) Method D-422. Results indicated soil comprised of 

4–13.9 percent (%) clay, 33.9–43.6% silt, 33.6–52.9% sand, and 0–20.6% gravel. 

2.2.2 Hydrogeology 

The Pleistocene sands and gravel within stream valleys form alluvial aquifers directly above 

bedrock that is between 15 and 25 ft thick in nearby Parkersburg, West Virginia. Groundwater 

within the fractured bedrock hills in the Facility area is generally between 30 and 40 ft bgs. In 

the area around the Facility, under normal conditions, the hydraulic gradient is such that 

groundwater flows northwest from the surrounding hills, towards the Ohio River, as shown on 

Figure 2-3. No groundwater wells were installed during the SI due to absence of shallow 

groundwater; thus, no groundwater elevation contour figures were able to be produced. During 

floods and high-water events that happen over a short period of time, the hydraulic gradient can 

reverse, causing river water to flow into and recharge the aquifer. This process during high-water 

events could affect the flow of contaminants in the aquifer. There is a semi-confining silt-clay 

layer over the alluvial aquifers; however, the bedrock and alluvium are hydraulically 

interconnected. This connectivity was determined by observing identical well responses during 

high-water events (AECOM 2020). 

West Virginia’s water resources predominantly come from the alluvial aquifers. Multiple entities 

draw water from the Middle Ohio South Watershed for public water supply. Fourteen cities 

receive most of their public water supply from groundwater of the Middle Ohio South 

Watershed, three of which specifically draw groundwater from Wood County. The City of 

Williamstown’s public water supply is completely sourced from groundwater within the Middle 

Ohio North Watershed (AECOM 2020). 

An EDRTM Report conducted a well search for a 1-mile radius surrounding the Facility. Using 

additional online resources, such as state and local GIS databases, wells were researched to a 

4-mile radius of the Facility. Based on the EDRTM Report, no public water supply wells, private

domestic wells, or monitoring wells were identified within 1 mile of the Facility. According to 

the U.S. Geological Survey (USGS) National Water Information System Mapper, there are two 

active USGS monitoring wells located within a 4-mile radius of the Facility: one 2.5 miles east 

and one 3.2 miles north of the Facility. Additional inactive USGS monitoring wells were 

identified within 4 miles and are shown on Figure 2-3 . Geographic information system (GIS) 

data for wells within a 4-mile radius of the Facility was unavailable at the city, county, state, and 

national levels. Therefore, it is possible that additional unidentified public or private wells may 

be located within 4 miles of the Facility. Drinking water at the Facility is provided by the City of 

Williamstown public water supply (AECOM 2020). 
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2.2.3 Hydrology 

The Ohio River is the major water feature near the Facility, beginning in Pittsburgh, 

Pennsylvania at the union of the Allegheny and Monongahela rivers. From there, the Ohio River 

flows southwest, ending at the border of Kentucky, Illinois, and Missouri, where it meets with 

the Mississippi River. Williamstown, West Virginia, is within the Middle Ohio South Watershed, 

one of many watersheds along the banks of the Ohio River. The Ohio River is used for 

recreational activities in the area of the Facility. The Middle Ohio South Watershed is spread 

through Wood, Wirt, Jackson, Roane, and Mason counties. There is no single, major tributary in 

this area of Wood County, as it consists of multiple Ohio River tributaries flowing through 

valleys, toward the river. This watershed contributes 7% of the public water supply within West 

Virginia. Wood County overall is one of three counties with the largest reported withdrawals by 

Large Quantity Users (LQUs) for public water supply. Approximately 80% of water withdrawn 

in Wood County for public supply is groundwater withdrawn by LQUs and groundwater 

privately withdrawn for self-supply (AECOM 2020). The City of Williamstown’s public water 

supply is completely sourced from groundwater within the Middle Ohio North Watershed. 

Surface water flow at the Facility follows topography (Figure 2-4). Surface water runoff on the 

northwest side of the Facility flows north to Plum Run. From Plum Run, water flows northwest 

to join Big Run. On the southern end of the Facility, surface water runoff flows southwest to Big 

Run. Big Run continues north for approximately 3 miles before discharging into the Ohio River, 

which has a southwestern flow (AECOM 2020). 

2.2.4 Climate 

Williamstown, West Virginia has a continental climate, which is characterized by four distinct 

seasons with moderately severe winters and warm, rainy summers. Topography and elevation are 

primary influences on climatic variations and temperature in West Virginia. The eastern region 

of West Virginia is generally a few degrees cooler than the western region of the state, including 

AASF #1, due to higher elevation. Climate data from Parkersburg, approximately 8.5 miles from 

the Facility, records an annual average high temperature of 65.3 degrees Fahrenheit (°F), the 

annual average low temperature is 44.1°F, annual rainfall precipitation is 42.09 inches (in.), and 

annual average snowfall precipitation is 11 in. (AECOM 2020). 

2.2.5 Current and Future Land Use 

AASF #1 currently resides on a portion of land leased from the Wood County Airport Authority 

under the terms of a 5-year lease. AASF #1 has been an operational military facility for an active 

National Guard unit since 1992, following the completion of construction. Future land use is not 

anticipated to change (AECOM 2020). 

2.2.6 Sensitive Habitat and Threatened/Endangered Species 

The following species are listed as federally endangered, threatened, proposed, and/or candidate 

species in Wood County, West Virginia (U.S. Fish and Wildlife Services 2022): 

 Snails: Flat-spired Three-toothed Snail (Triodopsis platysayoides) – Federally Threatened
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 Insects: Monarch Butterfly (Danaus plexippus) – Federal Candidate

 Mammal: Indiana Bat (Myotis sodalis) – Federally Endangered; Northern Long-eared Bat

(Myotis septentrionalis) – Federally Threatened; Virginia Big-eared Bat (Corynorhinus

townsendii virginianus) – Federally Endangered.

2.3 HISTORY OF PFAS USE 

Three AOIs were identified in the PA where AFFF may have been used, stored, disposed, or 

released historically at Williamstown AASF (AECOM 2020). AFFF may have historically been 

released at the Facility during a one-time fire training event at the burn pit area in the early 

2000s. Additional AFFF releases may also have occurred from annual fire training and refilling 

of fire extinguishers that took place at the wash pad. Additionally, AFFF in 5-gallon buckets 

were stored in the AFFF storage location. The potential release areas were grouped into three 

AOIs based on preliminary data and presumed groundwater flow directions. A description of 

each AOI is presented in Section 3. 
Williamstown

- AASF #1

Mid-Ohio Valley

Regional Airport

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Facility Data

Facility Boundary

0 1

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Data Sources:

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Figure 2-1

Facility Location

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Projection:........WGS 84 UTM 17N
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Williamstown

- AASF #1

Mid-Ohio Valley

Regional Airport

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0 1

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Data Sources:

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Figure 2-2

Topography

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Date:.....................September 2023

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Contour interval = 20 ft
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Mile Run

Carpenter Run

Worthington Creek

Fivemile Run

Big Run

Ohio River

Hogland

Run

Jackson Fork

Johnson Run

Sugarcamp Run

Laurel Fork

Long Run

Plum Run

Briscoe Run

Williams Creek

Bull Run

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Data Sources:

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AECOM 2020

Figure 2-3

Groundwater Features

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Facility Data

Facility Boundary

Well Type

A@ USGS Active Monitoring Well

A@ USGS Inactive Monitoring Well

Hydrology/Hydrogeology

Inferred Groundwater Flow Direction

Perennial Creek/Stream

Intermittent Creek/Stream

Wetlands

Date:.....................September 2023

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Projection:........WGS 84 UTM 17N
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Island Run

Big Run

Hogland Run

Carpenter Run

Jackson Fork

Sugarcamp Run

Plum Run

Big Run

Bull

Creek-Ohio

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Surface Water Flow Direction

Perrenial Creek/Stream

Intermittent Creek/Stream

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Watersheds

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Figure 2-4

Surface Water Features

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Date:....................September 2023

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Projection:........WGS 84 UTM 17N
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3. SUMMARY OF AREAS OF INTEREST

The PA evaluated areas where PFAS-containing materials may have been used, stored, disposed, 

or released historically. Based on the PA findings, three potential release areas were identified at 

Williamstown AASF #1 and grouped into three AOIs. The potential release areas are shown on 

Figure 3-1 and described below. 

3.1 AOI 1 – BURN PIT FTA 

In the early 2000s, the Williamstown AASF gave the adjacent Airport’s Fire Department a truck 

equipped with AFFF. The Airport Fire Department had permission to conduct a fire training 

event on AASF #1 property to see how the firetruck operated. For this exercise, a training 

location was chosen on the southeastern side of the Facility, near a large concrete pad. The exact 

location is unknown, but the estimated area is shown on Figure 3-1. The Airport Fire Department 

poured water into the pit, followed by fuel, then ignited the water-fuel mixture. The exercise fire 

was then extinguished using the Fire Department’s fire truck that contained AFFF. The quantity 

of foam used is unknown, but personnel remember the firetruck’s foam being sprayed for 

approximately 1 to 2 minutes. Following the exercise, the firetruck was not cleaned at the AASF 

#1 wash pad. Instead, the truck returned to the airport, and it is not known if the firetruck was 

washed after returning. This training event was a one-time occurrence. The foam released likely 

infiltrated soils on the surface as well as subsurface soils within the pit. The general burn pit 

location is a potential PFAS-release area (AECOM 2020). 

3.2 AOI 2 – WASH PAD 

Annual fire training took place with AFFF at the wash pad of the Facility. Interviewees recall 

AFFF being incorporated into the Facility’s emergency response equipment between 2000 and 

2001 and removed in 2010. During this period, annual fire training with AFFF took place on the 

Facility wash pad. During these events, wood was placed on the wash pads and ignited for 

participants to practice using Tri-MaxTM AFFF extinguishers. Interviewees recall Airport Fire 

Department personnel and employees from Fire Extinguisher Specialists, the company 

contracted for annual inspections of AFFF extinguishers, observing the annual fire training. 

Neither group brought outside extinguishers to the Facility, but Fire Extinguisher Specialists 

supplied propane torches to assist in lighting wood for the exercises. During these training 

events, the contents of one 150-pound, or 30-gallon, extinguisher would be expended in the wash 

pad area and rinsed down the drain with a water hose (AECOM 2020). 

Prior to 2006, the wash pad drain led to the Facility’s oil-water separator (OWS), then to a 

surface water outfall leading to Big Run, off-property. In 2006, the drainage system was 

restructured, and an equalization tank was installed. At this time, a valve was installed that 

directs liquid draining through the wash pad to the equalization tank, then to municipal sewage 

and the Williamstown wastewater treatment plant. Interviewees recall the valve being turned to 

the equalization tank during wash pad activities, including fire training. However, if the valve 

was not turned to the equalization tank, the wash pad water followed its original path to the 

OWS, followed by release to Big Run. Therefore, following renovations in 2006, AFFF from fire 

training activities followed the updated wash water path to the equalization tank, then to 

municipal sewage and a water treatment plant (AECOM 2020). 
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In addition to fire training exercises, the wash pad was used to dispose and refill off-specification 

AFFF. According to the Fire Extinguishers Inspection Sheet provided by AASF #1 personnel, 

there were 18 of the 30-gallon Tri-MaxTM AFFF extinguishers on the Facility that underwent 

hydrostatic testing every five years. When it was time for the extinguishers to be submitted for 

testing, the contents of each extinguisher were emptied into the wash pad before they were given 

to the contractor, Fire Extinguisher Specialists. At this time, Fire Extinguisher Specialists 

replaced them with re-certified extinguishers. This process was followed every five years, until 

AASF #1 had Tri-MaxTM AFFF extinguishers replaced by Purple K extinguishers in 2010. At 

this time, 18 extinguishers were emptied into the wash pad, and the empty extinguishers were 

given to the US Property and Fiscal Office. Disposal of large quantities of AFFF via wash pad 

drain potentially occurred before drainage renovations in 2006, as AFFF was acquired between 

2000 and 2001 and required service every five years. Therefore, it is likely that there was one 

disposal event prior to drainage renovations, resulting in AFFF going to Big Run, and one 

disposal event resulting in AFFF going to the municipal water treatment plant (AECOM 2020). 

The foam released during these annual training events and at the disposal of off-specification 

AFFF likely infiltrated surface water and sediment along drainage pathways from the outfall 

leading to Big Run and were introduced to the municipal sewer system. The pathway of potential 

contamination is dependent on the date of release. Though interviewees assert that the valve was 

turned to direct flow to municipal water treatment any time AFFF was used in the wash pad area 

following renovations, there is a degree of uncertainty due to the lack of documentation and 

reliance on interviewee recollection. The wash pad area is a potential PFAS-release area 

(AECOM 2020). 

3.3 AOI 3 – AFFF STORAGE 

While AFFF was in-use at AASF #1, 5-gallon buckets of Tri-MaxTM were stored in a Materials 

Storage Room on the property with oil and spill kits. To interviewee knowledge, no spills 

occurred in this location. Due to the potential for unintended leaks or spills of AFFF, this 

location is considered a potential PFAS-release area (AECOM 2020). 

3.4 ADJACENT SOURCES 

There are potential PFAS sources adjacent to the Williamstown AASF #1 that may impact PFAS 

concentrations in groundwater underlying the Facility. The Hard Landing and Airport Crash 

Simulation Training areas are located south and hydraulically upgradient of the AOIs, but there 

is no associated AFFF or PFAS release suspected at these sites. The Nozzle Test Area, which 

was used for testing that biannually released 5 to 10 gal of AFFF until 2017, is located south and 

hydraulically upgradient of the Facility. As such, the nozzle test area is a suspected adjacent 

PFAS release area and could potentially impact the groundwater underlying the Facility. The 

Williamstown Waste Water Treatment Plant is approximately 3.5 miles north and hydraulically 

downgradient of the AOIs. As such, this area is not expected to impact PFAS concentrations in 

the groundwater underlying the Facility. 
Ohio River

Big Run

Jackson Fork

Sugarcamp Run

Plum Run

Williams Creek

Hard Landing

Downed

Aircraft FTA

Nozzle

Test Area

Williamstown

WWTP

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Facility Data

Facility Boundary

Area of Interest

Potential PFAS Release

No Suspected PFAS Release

Hydrology

Surface Water Flow Direction

Inferred Groundwater Flow Direction

Perennial Creek/Stream

Intermittent Creek/Stream

0 1

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Data Sources:

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AECOM 2020

Figure 3-1

Areas of Interest

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Wash

Pad FTA

AFFF Storage

Burn Pit FTA

Oil-Water

Separator AOI 1

AOI 2

Big Run

Plum Run

AOI 3

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Date:....................September 2023

Prepared By:.............................EA

Prepared For:....................USACE

Projection:........WGS 84 UTM 17N
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4. PROJECT DATA QUALITY OBJECTIVES

As identified during the data quality objective (DQO) process and outlined in the SI Uniform 

Federal Policy- (UFP-) Quality Assurance Project Plan (QAPP) Addendum (EA Engineering, 

Science, and Technology, Inc., PBC [EA] 2022a), the objective of the SI is to identify whether 

there has been a release to the environment at the AOIs identified in the PA. For each AOI, 

ARNG determines if further investigation is warranted, a removal action is required to address 

immediate threats, or whether NFA is warranted. This SI evaluated groundwater and soil for 

presence or absence of relevant compounds at each of the sampled AOIs. 

4.1 PROBLEM STATEMENT 

ARNG may recommend AOIs for remedial investigation (RI) if site-related soil and groundwater 

samples have concentrations of the relevant compounds above the OSD risk-based SLs. The SLs 

are presented in Section 6.1 of this report. 

4.2 INFORMATION INPUTS 

Primary information inputs for the SI include the following: 

 The PA Report for Williamstown AASF #1 (AECOM 2020)

 Analytical data from soil samples collected as part of this SI in accordance with the UFPQAPP Addendum (EA 2022)

4.3 STUDY BOUNDARIES 

The scope of the SI was bounded horizontally by the property limits of the Facility (Figure 2-1). 

Off-Facility sampling was not included in the scope of this SI. If future off-Facility sampling is 

required, the proper stakeholders will be notified, and necessary rights-of-entry will be obtained 

by ARNG with property owner(s). Temporal boundaries were limited to the earliest available 

time field resources were available to complete the study. 

4.4 ANALYTICAL APPROACH 

Samples were analyzed by Eurofins Lancaster Laboratories Environmental, LLC, accredited 

under the Department of Defense (DoD) Environmental Laboratory Accreditation Program 

(ELAP); Accreditation No. 1.01). PFAS data underwent 100% Stage 2B validation in accordance 

with the DoD General Data Validation Guidelines (2019a) and DoD Data Validation Guidelines 

Module 3: Data Validation Procedure of PFAS Analysis by Quality Systems Manual (QSM) 

Table B-15 (2020). 

Data were compared to applicable SLs within this document and decision rules as defined in the 

SI UFP-QAPP Addendum (EA 2022a). 
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4.5 DATA USABILITY ASSESSMENT 

The Data Usability Assessment (DUA), which is provided in Appendix A, is an evaluation at the 

conclusion of data collection activities that uses the results of both data verification and 

validation in the context of the overall project decisions or objectives. Using both quantitative 

and qualitative methods, the assessment determines whether project execution and the resulting 

data have met installation-specific DQOs. Both sampling and analytical activities are considered 

to assess whether the collected data are of the right type, quality, and quantity to support the 

decision-making (DoD 2019a, 2019b; USEPA 2017). 

Based on the DUA, the environmental data collected during the SI were found to be acceptable 

and usable for this SI evaluation with the qualifications documented in the DUA and its 

associated data validation reports. These data are of sufficient quality to meet the objectives and 

requirements of the UFP-QAPP Addendum (EA 2022a). 
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5. SITE INSPECTION ACTIVITIES

This section describes the environmental investigation and sampling activities that occurred as 

part of the SI. The SI sampling approach was based on the findings of the PA and was 

implemented in accordance with the following approved documents: 

 Final PA Report, Army Aviation Support Facility #1, Williamstown, West

Virginia, dated July 2020 (AECOM 2020)

 Final Programmatic UPF-QAPP, SIs for PFAS Impacted Sites, ARNG

Installations, Nationwide, dated December 2020 (EA 2020a)

 Final SI UFP-QAPP Addendum, Army Aviation Support Facility #1,

Williamstown, West Virginia, dated March 2022 (EA 2022)

 Final Programmatic APP, Revision 1, dated November 2020 (EA 2020b)

 Final APP/Site Safety and Health Plan Addendum, Army Aviation Support

Facility #1, Williamstown, West Virginia, dated October 2021 (EA 2021).

The SI field activities were conducted from 31 January to 9 February 2023 and consisted of 

Sonic drilling and hand auger borings and soil sample collection. Two preparatory facility visits 

without intrusive work were also conducted on 15 November 2021 (source water sampling) and 

30 January 2023 (utility location). Field activities were conducted in accordance with the UFPQAPP Addendum (EA 2022a), except as noted in Section 5.9. 

The following samples were collected during the SI and analyzed for a subset of 24 PFAS via 

liquid chromatography/tandem mass spectrometry (LC/MS/MS) compliant with QSM Version 

5.3 Table B-15 to fulfill the project DQOs: 

 Fifty-Two (52) soil samples from 14 primary locations, 9 secondary (hand auger)

locations, and 3 boundary locations

 Twenty (20) quality assurance/quality control samples.

Figure 5-1 provides the sample locations for all media across the Facility. Table 5-1 presents 

the list of samples collected for each medium. Field documentation is provided in Appendix B. 

A log of Daily Notice of Field Activity was completed throughout the SI field activities, which 

is provided in Appendix B1. Sampling forms are provided in Appendix B2, and land survey 

data is provided in Appendix B3. Field change request forms are provided in Appendix B4. 

Additionally, a photographic log of field activities is provided in Appendix C. 

5.1 PRE-INVESTIGATION ACTIVITIES 

In preparation for the SI field activities, project team members participated in Technical Project 

Planning (TPP) meetings, performed utility clearance, and sampled decontamination source 

water. Details of these activities are presented below. 
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5.1.1 Technical Project Planning 

The U.S. Army Corps of Engineers (USACE) TPP Process, Engineers Manual (EM) 200-1-2 

(Department of the Army 2016) defines four phases to project planning: (1) defining the project 

phase; (2) determining data needs; (3) developing data collection strategies; and (4) finalizing the 

data collection plan. The process encourages stakeholder involvement in the SI, beginning with 

defining overall project objectives, including DQOs, and formulating a sampling approach to 

address the AOIs identified in the PA. 

A combined TPP Meeting 1 and 2 was held on 10 November 2021, prior to SI field activities. 

The combined TPP Meeting 1 and 2 was conducted in general accordance with EM 200-1-2. The 

stakeholders for this SI include the ARNG, WVARNG, USACE, West Virginia Department of 

Environmental Protection, and representatives familiar with the facility, the regulations, and the 

community. Stakeholders were provided the opportunity to make comments on the technical 

sampling approach and methods at the combined TPP Meeting 1 and 2. The outcome of the 

combined TPP Meeting 1 and 2 was memorialized in the SI QAPP Addendum (EA, 2022a). 

Note: A TPP Meeting (No. 3) will be held to discuss the results of the SI. Meeting minutes for 

TPP 3 will be included in Appendix D of this report. Future TPP meetings will provide an 

opportunity to discuss the results and findings, and future actions, where warranted. 

5.1.2 Utility Clearance 

EA contracted Ground Penetrating Radar Systems (GPRS) Inc., a private utility location service, 

to perform utility clearance at the Facility. Utility clearance was performed at each of the 

proposed boring locations on 30 January 2023 with input from the EA field team. General 

locating services and ground-penetrating radar were used to complete the clearance. The location 

AOI03-01 was offset approximately 40 ft east due to the presence of an obstruction in the 

original location. Location WAASF-02 was relocated 400ft southwest due to access and steep 

gradients. Hand auger clearances to a full 5 ft bgs for the remaining boring locations were 

unsuccessful due to intercepting weathered bedrock and resulted in a deviation from the UFPQAPP as outlined in Section 5.9. 

5.1.3 Source Water and PFAS Sampling Equipment Acceptability 

The potable water source used for decontamination of drilling equipment was sampled prior to 

the start of field activities. A sample from a potable water source via a spout located outside the 

hangar was collected on 15 November 2021, prior to mobilization, and analyzed for PFAS by 

LC/MS/MS compliant with QSM 5.3 Table B-15. These samples included multiple detections of 

PFAS relevant compounds at concentrations above one-fifth of their associated SL. As such, the 

water could not be used for decontamination and source-water collected at Wheeling AASF #2 

via a spigot outside the main hangar (using PFAS-free hose tubing), was brought for use at 

WAASF #1 during the SI. The results for Wheeling Army Aviation Support Facility #2 

(WHAASF #2) indicated that the water contained trace levels of PFOA detected at an estimated 

concentration less than one-tenth of the SL of 6 nanograms per liter (ng/L). Based on these lowlevel detections, the water was deemed acceptable for use in decontamination. Further discussion 
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is provided in the DUA (Appendix A). Analytical results for this sample can be found in 

Appendix F. 

Materials that were used within the sampling zone were confirmed as acceptable for use in the 

PFAS sampling environment. The checklist of acceptable materials for use in the PFAS sampling 

environment was provided in the Standard Operating Procedures appendix to the Programmatic 

UFP-QAPP (EA 2020a). 

5.2 HAND AUGER SOIL SAMPLING 

Eleven borings were advanced exclusively by hand auger; AOI01-06 through AOI01-10, AOI02-

05 through AOI02-08, as well as two additional hand auger samples obtained at locations 

AOI02-01 and WAASF-03 (see Section 5.9). 

5.3 SOIL BORINGS AND SOIL SAMPLING 

Each boring was pre-cleared by EA’s drilling subcontractor, Cascade Drilling, using a hand 

auger to verify utility clearance in the shallow subsurface where utilities would typically be 

encountered (see Section 5.9). Soil samples collected from depths shallower than 5 ft bgs were 

collected using the hand auger. The hand auger was decontaminated between each boring to 

ensure no cross-contamination occurred between samples. Soil sample locations are shown on 

Figure 5-1 and described in the subsequent section. Non-dedicated sampling equipment (i.e., 

hand auger) was decontaminated between sampling locations. 

Beyond 5 ft depth, soil samples were collected via Sonic drilling methods in accordance with the 

UFP-QAPP Addendum (EA 2022). 

Three discrete soil samples were collected for chemical analysis from each soil boring (except as 

noted in Section 5.9); one sample at the surface (0 to 2 ft bgs) and two subsurface soil samples. 

One subsurface soil sample was collected from the midpoint of the boring (not to exceed 15 ft 

bgs), and one was collected approximately one foot above the terminal depth of the boring. 

Shallow groundwater was not encountered at the Facility during the SI field event. Total boring 

completion depths ranged from ~5 to 44 ft bgs. 

Soil sample locations are shown on Figure 5-1, and boring sample depths are provided in Table 

5-1. The soil boring locations were selected based on the AOI information provided in

the PA (AECOM 2020) and as agreed upon by stakeholders during the TPP and review of the 

UFP-QAPP Addendum (EA 2022). Several boring locations were adjusted and offset for various 

reasons including drill rig access, utility avoidance, and drill equipment refusal. 

During the mobilization, the soil cores were continuously logged for lithological descriptions by 

a field geologist using the Unified Soil Classification System (USCS). A photoionization 

detector (PID) was used to screen the breathing zone during boring activities as a part of personal 

safety requirements. Observations and measurements were recorded on sampling forms 

(Appendix B2) and in a non-treated field logbook. Depth interval, recovery thickness, PID 

concentrations, moisture, relative density, Munsell color, and USCS texture were recorded. The 

boring logs are provided in Appendix E. 
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Each sample was collected into a laboratory-supplied PFAS-free high-density polyethylene 

bottle and labeled using a PFAS-free marker or pen. Samples were packaged on ice and 

transported via Federal Express under standard chain-of-custody procedures to the laboratory 

and analyzed for PFAS (LC/MS/MS compliant with QSM Version 5.3 Table B-15), total organic 

carbon (TOC) (USEPA Method 9060A), pH (USEPA Method 9045D), and grain size (ASTM 

D422) in accordance with the UFP-QAPP Addendum (EA 2022). 

Field duplicate samples were collected at a rate of 10% and analyzed for the same parameters as 

the accompanying samples. Matrix spike (MS)/matrix spike duplicates (MSDs) were collected at 

a rate of 5% and analyzed for the same parameters as the accompanying samples. In instances 

when non-dedicated sampling equipment was used, such as a hand auger for the shallow soil 

samples, one equipment blank (EB) was collected per day and analyzed for the same parameters 

as the soil samples. A temperature blank was placed in each cooler to ensure that samples were 

preserved at or below 6 degrees Celsius (°C) during shipment. 

5.4 TEMPORARY WELL INSTALLATION AND GROUNDWATER GRAB

SAMPLING 

There were no temporary wells installed at the Williamstown AASF #1 Facility because shallow 

refusal was reached prior to encountering groundwater. Thus, no grab groundwater samples were 

able to be collected for any AOI at the Facility. Shallow groundwater is a pathway of concern in 

the SI.

5.5 SYNOPTIC WATER LEVEL MEASUREMENTS

No temporary wells were installed during this SI field event. Due to this, no synoptic gauging 

event occurred, and no groundwater elevation contour maps were created. 

5.6 SURVEYING 

No temporary wells were installed so no surveying was performed. 

5.7 INVESTIGATION-DERIVED WASTE

As of the date of this report, the disposal of PFAS investigation-derived waste (IDW) is not 

regulated federally. PFAS IDW generated during the SI is considered non-hazardous waste and 

was managed in accordance with the UFP-QAPP Addendum (EA 2022). 

Soil IDW (i.e., soil cuttings) and liquid IDW (i.e., decon water and drilling water) generated 

during the SI activities was containerized (except as noted in Section 5.9) in properly labeled 55-

gallon drums (two water, eleven soil) and staged within a connex box at an approved location at 

the western end of the parking lot near AOI 3. The solid and liquid IDW will be sampled and

disposed offsite via a Resource Conservation and Recovery Act Subtitle C landfill. Specifics on 

the disposal of solid and liquid IDW will be addressed in an IDW Technical Memorandum. 
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Other solids such as spent personal protective equipment, plastic sheeting, tubing, rope, and 

unused monitoring well construction materials generated during the field activities were disposed 

at a licensed solid waste landfill. 

5.8 LABORATORY ANALYTICAL METHODS 

Samples were analyzed for PFAS by LC/MS/MS compliant with QSM Version 5.3 Table B-15 

at Eurofins Lancaster Laboratories Environmental, LLC, in Lancaster, Pennsylvania, a DoD 

ELAP- and National Environmental Laboratory Accreditation Program-certified laboratory. 

Soil samples were also analyzed for TOC using USEPA Method 9060A, pH by USEPA Method 

9045D, and grain size by ASTM D422. 

5.9 DEVIATIONS FROM SITE INVESTIGATION UFP-QAPP ADDENDUM 

Deviations from the UFP-QAPP Addendum occurred based on field conditions. These deviations 

were discussed between EA, ARNG, and USACE. Deviations from the UFP-QAPP Addendum 

(EA 2022) are noted below and are documented in the field change requests forms in Appendix 

B4: 

 During utility clearance, it was noted that WAASF-02 was located in a position that was

difficult to access via drill rig. The location was relocated approximately 400 ft

southwest, inside the fence line and downgradient of all associated AOIs. Full details can

be found in Appendix B4.

 Due to shallow bedrock and/or refusal encountered between 0 and 5 ft bgs across the site,

the majority of borings were not cleared via hand auger to the full 5 ft bgs but went to at

least to the frost line between 3 and 4 ft bgs

 Refusal/bedrock was encountered at variable depths across the Facility. As such, the third

sample outlined in the UFP-QAPP Addendum (EA 2022) was not collected from boring

locations AOI01-01 and AOI01-10, due to unanticipated shallow depths to bedrock (less

than 10 ft bgs).

 On the first day of drilling (31 January 2023), silt and clay (between 10 and 20 ft bgs), a

stiff clay (beginning at 20 ft bgs), and refusal attributed to weathered rock (at 31 ft bgs)

was encountered in the WAASF-03. No groundwater was encountered and no sediments

with moisture content above “moist” quality were observed in the boring. A project team

call between ARNG G-9 and EA was held to determine a path forward if similar

subsurface conditions were encountered at subsequent locations. Based on the call, it was

determined a well would not be installed if these conditions occurred; thus, no temporary

wells were installed at any AOI due to these similar conditions being encountered in

every boring.

 Due to shallow bedrock encountered and/or no groundwater observed at each AOI, a

decision was made by ARNG G-9 to add nine additional surface soil (hand auger; 0 to 2ft
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bgs) samples to ensure there was complete representation and capture of each AOI 

release area. AOI 1 added five locations – AOI01-06 through AOI01-10 – and AOI 2 

added four locations – AOI02-05 through AOI02-08. 

 Due to the extensive, dense clay encountered at WAASF-03 during drilling, source-water

(obtained from WHAASF #2) was introduced to alleviate friction generated-heat on the

core barrel; as a result, two 55-gallon drums of water were collected following pumping

of the completed boring. Similar circumstances generated half of a 55-gallon drum at

AOI02-01. Per the UFP-QAPP Addendum (EA 2022), “Liquid IDW generated during SI

activities (i.e., drilling and decontamination fluids) will be discharged directly to the

ground surface slightly downgradient of the source of generation. This IDW will not be

sampled and will assume the PFAS characteristics of the associated groundwater samples

collected from that source location.” Under this work plan, collected water was

subsequently discharged to the surface at each respective location. However, based on

discussions with ARNG G-9, WVDEP had made a statement subsequent to the

finalization of the QAPP that all liquid IDW should be drummed and staged until receipt

of SI sampling results. Based on this statement, EA collected confirmatory surface soil

samples (0 to 2ft bgs) at each location where water was discharged, labeled AOI02-01HA

and WAASF-03HA, and analyzed them for PFAS-relevant compounds. Further, solid

and liquid IDW was containerized following this added procedure.
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Table 5-1. Site Inspection Samples by Medium 

AASF #1, Williamstown, West Virginia 

Site Inspection Report

Sample Identification 

Sample Collection 

Date

Sample Depth 

(ft bgs)

LC/MS/MS 

compliant with QSM 

5.3 Table B-15 TOC1 pH2

Grain 

Size3 Comments 

 Soil Samples 

AOI01-01-SB-[0-2] 2/8/2023 0-2 X MS/MSD

Sample 

Collected 

AOI01-01-SB-[4-5] 2/8/2023 4-5 X

AOI01-02-SB-[0-2] 2/9/2023 0-2 X

AOI01-02-SB-[14-15] 2/9/2023 14-15 X

AOI01-02-SB-[28-29] 2/9/2023 28-29 X

AOI01-03-SB-[0-2] 2/9/2023 0-2 X X X X MS/MSD

Sample 

Collected 

AOI01-03-SB-[11-12] 2/9/2023 11-12 X

AOI01-03-SB-[23-24] 2/9/2023 23-24 X

AOI01-04-SB-[0-2] 2/8/2023 0-2 X

AOI01-04-SB-[7-8] 2/8/2023 7-8 X

AOI01-04-SB-[14-15] 2/8/2023 14-15 X

AOI01-05-SB-[0-2] 2/8/2023 0-2 X

AOI01-05-SB-[4-6] 2/8/2023 4-6

AOI01-06-HA-[0-2] 2/9/2023 0-2 X Hand auger

only sample 

AOI01-07-HA-[0-2] 2/9/2023 0-2 X Hand auger

only sample; 

MS/MSD 

Sample 

Collected 

AOI01-08-HA-[0-2] 2/9/2023 0-2 X Hand auger

only sample 

AOI01-09-HA-[0-2] 2/9/2023 0-2 X Hand auger

only sample

AOI01-10-HA-[0-2] 2/9/2023 0-2 X Hand auger

only sample 

AOI02-01-HA-[0-2] 2/9/2023 0-2 X Hand auger

only sample – 

surface soil 

confirmation 

sample from 

IDW dump

AOI02-01-SB-[0-2] 2/1/2023 0-2 MS/MSD

Sample 

Collected 

AOI02-01-SB-[14-15] 2/1/2023 14-15 X

AOI02-01-SB-[34-35] 2/1/2023 34-35 X

AOI02-02-SB-[0-2] 2/2/2023 0-2 X

AOI02-02-SB-[9-10 2/1/2023 9-10 X

AOI02-02-SB-[19-20] 2/1/2023 19-20 X X X X

AOI02-03-SB-[0-2] 2/1/2023 0-2 X

AOI02-03-SB-[9-10 2/1/2023 9-10 X

AOI02-03-SB-[19-20] 2/1/2023 19-20 X

AOI02-04-SB-[0-2] 2/1/2023 0-2 X MS/MSD

Sample 
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Table 5-1. Site Inspection Samples by Medium 

AASF #1, Williamstown, West Virginia 

Site Inspection Report

Sample Identification 

Sample Collection 

Date

Sample Depth 

(ft bgs)

LC/MS/MS 

compliant with QSM 

5.3 Table B-15 TOC1 pH2

Grain 

Size3 Comments 

Collected 

AOI02-04-SB-[9-10] 2/1/2023 9-10 X

AOI02-04-SB-[19-20] 2/1/2023 19-20 X

AOI02-05-HA-[0-2] 2/6/2023 0-2 X

AOI02-06-HA-[0-2] 2/6/2023 0-2 X

AOI02-07-HA-[0-2] 2/6/2023 0-2 X

AOI02-08-HA-[0-2] 2/6/2023 0-2 X

AOI03-01-SB-[0-2] 2/3/2023 0-2 X

AOI03-01-SB-[8-9] 2/3/2023 8-9 X

AOI03-01-SB-[17-18] 2/3/2023 17-18 X

AOI03-02-SB-[0-2] 2/7/2023 0-2 X X X X

AOI03-02-SB-[9-10] 2/7/2023 9-10 X

AOI03-02-SB-[19-20] 2/7/2023 19-20 X

WAASF-01-SB-[0-2] 2/7/2023 0-2 X

WAASF-01-SB-[14-15] 2/7/2023 14-15 X

WAASF-01-SB-[43-44] 2/7/2023 43-44 X

WAASF-02-SB-[0-2] 2/7/2023 0-2 X

WAASF-02-SB-[11-12] 2/7/2023 11-12 X

WAASF-02-SB-[23-24] 2/7/2023 23-24 X

WAASF-03-HA-[0-2] 2/7/2023 0-2 X Hand auger

only sample – 

surface soil 

confirmation 

sample from 

IDW dump

WAASF-03-SB-[0-2] 1/31/2023 0-2 X

WAASF-03-SB-[14-15] 1/31/2023 14-15 X 

WAASF-03-SB-[30-32] 1/31/2023 30-32 X 

WAASF-03-SB-[25-26] 1/31/2023 25-26 X X X 

DUP1 1/31/2023 0-2 X Field Duplicate

of WAASF-03-

SB-[0-2] 

DUP2 2/2/2023 0-2 X Field Duplicate

of AOI02-02-

SB-[0-2] 

DUP3 2/6/2023 0-2 X Field Duplicate

of AOI02-06-

HA-[0-2] 

DUP4 2/7/2023 11-12 X Field Duplicate

of WAASF-04-

SB-[11-12] 

DUP5 2/8/2023 0-2 X Field Duplicate

of AOI01-05-

SB-[0-2] 

DUP6 2/8/2023 0-2 X Field Duplicate

of AOI01-04-

SB-[0-2] 

Blank Samples

EB-01312023 1/31/2023 -- X Equipment

Blank
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Table 5-1. Site Inspection Samples by Medium 

AASF #1, Williamstown, West Virginia 

Site Inspection Report

Sample Identification 

Sample Collection 

Date

Sample Depth 

(ft bgs)

LC/MS/MS 

compliant with QSM 

5.3 Table B-15 TOC1 pH2

Grain 

Size3 Comments 

EB-02012023 2/01/2023 -- X Equipment

Blank

EB-02022023 2/02/2023 -- X Equipment

Blank

EB-02032023 2/03/2023 -- X Equipment

Blank

EB-02062023 2/06/2023 -- X Equipment

Blank

EB-02072023 2/07/2023 -- X Equipment

Blank

EB-02082023 2/08/2023 -- X Equipment

Blank

Notes: 

1 = TOC by USEPA Method 9060A 

2 = pH by USEPA Method 9045D 

3 = Grain Size by ASTM International D422 

ft = foot (feet) 

bgs = below ground surface 
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Table 5-2. Soil Boring Depths and Temporary Well Screen Intervals 

AASF #1, Williamstown, West Virginia 

Site Inspection Report 

AOI Boring ID

Soil Boring Depth 

(ft bgs)

Temporary Well Screen 

Interval1

(ft bgs) 

1 

AOI01-01 5 --

AOI01-02 30 —

AOI01-03 30 —

AOI01-04 20 —

AOI01-05 8 —

AOI01-06-HA 2 —

AOI01-07-HA 2 —

AOI01-08-HA 2 —

AOI01-09-HA 2 —

AOI01-10-HA 2 —

2 

AOI02-01-HA 2 —

AOI02-01 40 —

AOI02-02 20 —

AOI02-03 20 —

AOI02-04 20 —

AOI02-05-HA 2 —

AOI02-06-HA 2 —

AOI02-07-HA 2 —

AOI02-08-HA 2 —

3 

AOI03-01 18 —

AOI03-02 20 —

Facility Boundary 

WAASF-01 44 —

WAASF-02 20 —

WAASF-03 33 —

WAASF-03-HA 2 —

Notes: 

1 = No temporary wells were installed at any AOI; thus, there are no well screen intervals to report 

HA = Hand Auger; location was exclusively a hand auger soil sample 
AOI01-03

AOI01-04

AOI01-02

AOI01-05

AOI01-01

WAASF-03

WAASF-01

WAASF-02

Oil-Water Separator

AOI01-06-HA

AOI01-07-HA

AOI01-08-HA AOI01-09-HA

AOI01-10-HA

Big Run

Plum Run

WAASF-03-HA

^_

WV

Facility Data

Facility Boundary

Area of Interest

Potential PFAS Release

Sample Locations

Soil Boring

Surface Soil Sample

Hydrology

Surface Water Flow Direction

Inferred Groundwater Flow Direction

Perennial Creek/Stream

Intermittent Creek/Stream

3

0 1,000

Feet

Data Sources:

ESRI 2020

AECOM 2020

Figure 5-1

Site Inspection Sample Locations

Army National Guard Site Inspections

Site Inspection Report

Williamstown AASF #1, West Virginia

Path: G:\Federal\Nationwide\PFAS\MAES_634250383\PROJECTS\SIReport\Williamstown\WilliamstownSI.aprx\Figure 5-1 Site Inspection Sample Locations

AOI02-02

AOI02-01

AOI02-03

AOI02-04

AOI02-05-HA

AOI02-06-HA

AOI02-07-HA

AOI02-08-HA

Wash Pad

FTA

AOI02-01-HA

AOI 2

AOI03-01

AOI03-02

AFFF Storage

AOI 3

0 75

Feet

0 100

Feet

Date:.....................September 2023

Prepared By:.............................EA

Prepared For:....................USACE

Projection:........WGS 84 UTM 17N
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6. SITE INSPECTION RESULTS

This section presents the analytical results of the SI. The SLs used in this evaluation are 

presented in Section 6.1 in Table 6-1. A discussion of the results for the AOIs and boundary 

areas is provided in Sections 6.3 through 6.6. Tables 6-2 through 6-4 present results for soil for 

the relevant compounds. Tables that contain all results are provided in Appendix F, and the 

laboratory reports are provided in Appendix G. 

6.1 SCREENING LEVELS 

The DoD has adopted a policy to retain facilities in the CERCLA process based on risk-based 

SLs for soil and groundwater, as described in a memorandum from the OSD dated 6 July 2022 

(Assistant Secretary of Defense 2022). The ARNG program under which this SI was performed 

follows this DoD policy. Should the maximum site concentration for sampled media exceed the 

SLs established in the OSD memorandum, the AOI will proceed to the next phase under 

CERCLA. The SLs established in the OSD memorandum apply to the five compounds presented 

on Table 6-1. 

Table 6-1. Screening Levels (Soil and Groundwater) 

Analyte2

Residential 

(Soil) 

(μg/kg)1 

0 to 2 ft bgs

Industrial/Commercial 

Composite Worker 

(Soil) 

(μg/kg) 1 

2 to 15 ft bgs

Tap Water 

(Groundwater) 

(ng/L) 1 

PFOA 19 250 6

PFOS 13 160 4

PFBS 1,900 25,000 601

PFHxS 130 1,600 39

PFNA 19 250 6

Notes: 

1. Assistant Secretary of Defense. July 2022. Risk-Based SLs in Groundwater and Soil using USEPA’s Regional

Screening Level Calculator. Hazard Quotient=0.1. May 2022.

2. Of the six PFAS compounds presented in the 6 July 2022 OSD memorandum, HFPO-DA (commonly referred

to as GenX) was not included as an analyte at the time of this SI. Based on the CSM developed during the PA

and revised based on SI findings, the presence of HFPO-DA is not anticipated at the Facility because HFPODA is generally not a component of MIL-SPEC AFFF and based on its history including distribution

limitations that restricted use of GenX, it is generally not a component of other products the military used. In

addition, it is unlikely that GenX would be an individual chemical of concern in the absence of other PFAS

The data in the subsequent sections are compared against the SLs presented in Table 6-1. The 

SLs for groundwater are based on direct ingestion. The SLs for soil are based on incidental 

ingestion and are applied to the depth intervals reasonably anticipated to be encountered by the 

receptors identified at the Facility; the residential scenario is applied to surface soil results (0 to 

2 ft bgs) and the industrial/commercial worker scenario is applied to shallow subsurface soil 

results (2 to 15 ft bgs). The SLs are not applied to deep subsurface soil results (greater than 15 ft 

bgs) because 15 ft is the anticipated limit of construction activities. 
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6.2 SOIL PHYSICOCHEMICAL ANALYSES 

To provide basic soil parameter information, soil samples were analyzed for grain size, TOC, 

and pH, which are important for evaluating transport through the soil medium. Appendix F

contains the results of the grain size, TOC, and pH sampling. 

The data collected in this investigation will be used in subsequent investigations, where 

appropriate, to assess fate and transport. According to the Interstate Technology Regulatory 

Council (ITRC), several important PFAS partitioning mechanisms include hydrophobic and 

lipophobic effects, electrostatic interactions, and interfacial behaviors. At relevant environmental 

pH values, certain PFAS are present as organic anions; and are therefore, relatively mobile in 

groundwater (Xiao et al. 2015), but tend to associate with the organic carbon fraction that may be 

present in soil or sediment (Higgins and Luthy 2006; Guelfo and Higgins 2013). When sufficient 

organic carbon is present, organic carbon normalized distribution coefficients (Koc values) can 

help in evaluating transport potential, though other geochemical factors (e.g., pH and presence of 

polyvalent cations) may also affect PFAS sorption to solid phases (ITRC 2018). 

Soil pH and TOC were analyzed in soil samples AOI01-03-SB-[0-2] and AOI02-02-SB-[19-20], 

AOI03-02-SB2-0-2, and WAASF-03-SB-[25-26]. Results were similar, with pH ranging from 

7.4 to 8.9, and TOC results ranged from 450 to 12,000 milligrams per kilogram (mg/kg). The 

grain size analysis showed varying amounts of clay (4–13.9%), sand (33.6–52.9%), silt (33.9–

43.6%), and minor gravel. This result corresponds to a soil texture of sandy loam. 

6.3 AOI 1 

This section presents the analytical results for soil in comparison to SLs for AOI 1, which 

includes the Burn Pit FTA. The soil results are summarized on Tables 6-2 through 6-4 and 

presented on Figures 6-1 through 6-5. 

6.3.1 AOI 1 – Soil Analytical Results 

Tables 6-2 through 6-4 summarize the detected compounds in soil. Figures 6-1 through 6-5

present the ranges of detections in soil. 

Soil was sampled in ten boring locations associated with the potential release areas at AOI 1 

(AOI01-06 through AOI01-10 were exclusively hand auger samples from 0 to 2ft bgs). Soil was 

sampled from three intervals at locations AOI01-02 through AOI01-04; due to shallow refusal, 

locations AOI01-01 and AOI01-05 only had two intervals. Samples were collected from surface 

soil (0 to 2 ft bgs), shallow subsurface soil (4 to 15 ft bgs), and deep subsurface soil (17 to 29 ft 

bgs). 

Nine of 10 locations had detections of PFOA in surface soil (0 to 2ft bgs) under the 19 μg/kg SL. 

Concentrations ranged from (estimated) 0.29 J to 1.2 μg/kg in AOI01-09 and AOI01-07, 

respectively. One location (AOI01-09) had a PFOS detection with an estimated concentration of 

0.29 J μg/kg, below the 13 μg/kg SL. There were no other detections of relevant compounds in 

surface soil. 
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There was one detection of PFOA in subsurface soil at AOI01-05 at an estimated concentration 

of 0.26 J μg/kg, which was below the SL of 250 μg/kg. There were no other detections of 

relevant compounds in any shallow or deep subsurface sample. 

6.3.2 AOI 1 – Groundwater Analytical Results 

Groundwater was not encountered at any location within AOI 1. Due to this, no temporary wells 

were installed, and no grab groundwater samples were collected or analyzed. 

6.3.3 AOI 1 – Conclusions 

Two of the five relevant compounds were detected in soil at AOI 1. PFOA and PFOS were 

detected well below their respective SLs. No groundwater samples were collected at any location 

at AOI 1. Based on the results of the soil analytics, and the lack of any groundwater analytics, no 

further evaluation at AOI 1 is warranted. 

6.4 AOI 2 

This section presents the analytical results for soil in comparison to SLs for AOI 2, which 

includes the Wash Pad FTA. The soil results are summarized in Tables 6-2 through 6-4 and are 

presented on Figures 6-5 through 6-10. 

6.4.1 AOI 2 – Soil Analytical Results 

Tables 6-2 through 6-4 summarize the detected compounds in soil. Figures 6-6 through 6-10

present the ranges of detections in soil. 

Soil was sampled in nine boring locations associated with the potential release areas at AOI 2 

(AOI02-05 through AOI02-08 were exclusively hand auger samples from 0 to 2ft bgs; AOI02-

01HA was an additional hand auger sample collected at this location after drilling water was 

discharged, see Section 5.9). Soil was sampled from three intervals at locations AOI02-01 

through AOI02-04. Samples were collected from surface soil (0 to 2 ft bgs), shallow subsurface 

soil (9 to 15 ft bgs), and deep subsurface soil (19 to 35 ft bgs). 

Four of the five relevant compounds (PFOA, PFOS, PFNA, and PFHxS) were detected in 

surface soils in one or more locations at AOI 2. PFOA was detected at estimated concentrations 

ranging from 0.33 J μg/kg (AOI02-04) to 1.2 J+ μg/kg (AOI02-06), below the 19 μg/kg SL. 

PFOS was detected above and below the SL of 13 μg/kg, with concentrations ranging from 

(estimated) 0.25 J μg/kg (AOI02-02) to 73 μg/kg at AOI02-03, which was the only exceedance 

at AOI 2. PFNA was detected at one location (AOI02-01-HA) with an estimated concentration of 

0.25 J μg/kg, below the SL of 19 μg/kg. PFHxS was detected below the 130 μg/kg SL with 

concentrations ranging from (estimated) 0.29 J to 3.0 μg/kg in AOI02-08HA and AOI02-03, 

respectively. 

In shallow subsurface soil, one location (AOI02-03) had a detection of PFBS with an estimated 

concentration of 0.84 J μg/kg, below the 25,000 μg/kg SL. There were no other detections of 

relevant compounds in shallow or deep subsurface soil. 
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6.4.2 AOI 2 – Groundwater Analytical Results 

Groundwater was not encountered at any location within AOI 2. Therefore, no temporary wells 

were installed, and no grab groundwater samples were collected or analyzed. 

6.4.3 AOI 2 – Conclusions 

Four of the five relevant compounds (PFOA, PFOS, PFHxS, PFNA,) were detected in surface 

soils at AOI 2 below their respective SLs, with the exception of AOI02-03, which had an 

exceedance for PFOS with a concentration of 73 μg/kg. One location had a detection below the 

SL for PFBS in shallow subsurface soil. No groundwater samples were collected, and thus no 

groundwater analytical data is available for AOI 2. Based on the exceedance of an SL in soil, 

further evaluation at AOI 2 is warranted. 

6.5 AOI 3 

This section presents the analytical results for soil in comparison to SLs for AOI 3, which 

includes the AFFF Storage location. The soil results are summarized on Tables 6-2 through 

6-4 and presented on Figures 6-5 through 6-10.

6.5.1 AOI 3 – Soil Analytical Results 

Tables 6-2 through 6-4 summarize the detected compounds in soil. Figures 6-6 through 6-10

present the ranges of detections in soil. 

Soil was sampled at two locations associated with release areas at AOI 3. Soil was sampled from 

three intervals at each location. Samples were collected from surface soil (0 to 2 ft bgs), shallow 

subsurface soil (8 to 10 ft bgs), and deep subsurface (17 to 20 ft bgs). 

Two relevant compounds were detected in surface soil at one location, AOI03-01. PFOA was 

detected at an estimated concentration of 0.37 J μg/kg, below the SL of 19 μg/kg. PFOS was 

detected at an estimated concentration of 0.64 J μg/kg below the SL of 13 μg/kg. No other 

relevant compounds were detected. 

There was one detection of PFOA in shallow subsurface soil at AOI3-02 at an estimated 

concentration of 0.45 J μg/kg, which is below the associated SL of 250 μg/kg. There were no 

other detections of relevant compounds in shallow subsurface soil. 

There were no detections of relevant compounds at any location in deep subsurface soil at 

AOI 3. 

6.5.2 AOI 3 – Groundwater Analytical Results 

Groundwater was not encountered at any location within AOI 3. Therefore, no temporary wells 

were installed, and no grab groundwater samples were collected or analyzed. 
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6.5.3 AOI 3 – Conclusions 

None of the relevant compounds were detected in soil above their respective SLs. No 

groundwater samples were collected, and thus no groundwater analytical data is available for 

AOI 3. Based on the results of the soil analytics, and the lack of any groundwater analytics, no 

further evaluation at AOI 3 is warranted. 

6.6 FACILITY BOUNDARY 

This section presents the analytical results for soil in comparison to SLs for the Facility 

Boundary locations, which includes WAASF-01 (near western Facility boundary, roughly 700 ft 

slightly northwest of AOIs 2 and 3 and downgradient to potential contaminants leaving the 

central portion of the Facility), WAASF-02 (at the northwest Facility boundary, roughly 1200 ft 

north of WAASF-01 and downgradient of all AOIs and to contaminants leaving the Facility), 

and WAASF-03 (roughly 300 ft south of AOIs 2 and 3 at the OWS outfall). The soil results are 

summarized in Tables 6-2 through 6-4 and presented on Figures 6-1 through 6-5 as well. 

6.6.1 Soil Analytical Results 

Tables 6-2 through 6-4 summarize the detected compounds in soil. Figures 6-1 through 6-5 

present the ranges of detections in soil. 

Soil was sampled at three locations associated with the Facility Boundary. These three borings 

were associated with locations downgradient of AOIs 1, 2 and 3 via surface water and presumed 

groundwater flow direction. Soil was sampled from three intervals at each location. An 

additional surface soil sample was collected at WAASF-03 (hand auger sample WAASF-03-HA) 

due to drilling water being discharged at this location (see Section 5.9). Samples were collected 

from surface soil (0 to 2 ft bgs), shallow subsurface soil (11 to 15 ft bgs), and deep subsurface 

soil (23 to 44 ft bgs). 

PFOA and PFOS relevant compounds were detected in surface soils at the boundary locations. 

PFOA was detected in WAASF-01, WAASF-03, and WAASF-03HA with concentrations 

ranging from (estimated) 0.3 J μg/kg in WAASF-01 to 1.7 μg/kg in WAASF-03-HA, below the 

19 μg/kg SL. PFOS was detected in WAASF-01 at an estimated concentration of 0.55 J μg/kg, 

below the SL of 13 μg/kg. No other relevant compounds were detected in surface soil in Facility 

Boundary samples. 

There were no detections of relevant compounds in the shallow subsurface or deep subsurface 

soil intervals Facility Boundary Samples. 

6.6.2 Groundwater Analytical Results 

Groundwater was not encountered at any Facility Boundary location. Therefore, no temporary 

wells were installed, and no groundwater samples were collected or analyzed.
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Site Inspection Report

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Analyte Screening Level1,2 Result Qual Result Qual Result Qual Result Qual R

PFAS by LC/MS/MS compliant with QSM Version 5.3 Table B-15 (μg/kg)Perfluorobutanesulfonic acid (PFBS) 1900 ND U ND U ND U ND U Perfluorohexanesulfonic acid (PFHxS) 130 ND U ND U ND U ND U Perfluorononanoic acid (PFNA) 19 ND U ND U ND U ND U Perfluorooctanesulfonic acid (PFOS) 13 ND U ND U ND U ND U Perfluorooctanoic acid (PFOA) 19 0.31 J 0.52 J 0.73 ND U 0

Notes:J = Estimated concentration.

J- = Estimated concentration, biased low.J+ = Estimated concentration, biased high.

Table 6-2. PFOA, PFOS, PFBS, PFNA, and PFHxS Results in Surface 

Site Inspection Report, AASF #1, Williamstown, West Virginia

Location ID AOI01-01 AOI01-02 AOI01-03 AOI01-04 

Sample Name AOI01-01-SB-0-2 AOI01-02-SB-0-2 AOI01-03-SB-0-2 AOI01-04-SB-0-2 

Parent Sample ID A

Sample Date 2/8/2023 2/9/2023 2/9/2023 2/8/2023 

Sample Depth (ft bgs) 0-2 0-2 0-2 0-2 

U = The analyte was not detected at a level greater than or equal to the adjustedLimit of Detection (LOD).1. Assistant Secretary of Defense. July 2022. Risk-Based Screening Levels inGroundwater and Soil using EPA’s Regional Screening Level Calculator. HazardQuotient (HQ)=0.1. May 2022.2. The Screening Levels for soil are based on a residential scenario for directingestion of contaminated soil.

Values exceeding the Screening Level are shaded gray.μg/kg = Microgram(s) per kilogramft bgs = Foot (feet) below ground surfaceND = Analyte not detected above the LOD (LOD values are presented in Appendix F).Qual = Qualifier

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AOI = Area of InterestDUP = DuplicateLC/MS/MS = Liquid chromatography/tandem mass spectrometry QSM = Quality Systems Manual
Site Inspection Report

Williamstown AAFS #1, West Virginia 

Analyte Screening Level1,2

PFAS by LC/MS/MS compliant with QSM Version 5.3 Table B-15 (μg/kg)Perfluorobutanesulfonic acid (PFBS) 1900Perfluorohexanesulfonic acid (PFHxS) 130Perfluorononanoic acid (PFNA) 19Perfluorooctanesulfonic acid (PFOS) 13Perfluorooctanoic acid (PFOA) 19Notes:J = Estimated concentration.J- = Estimated concentration, biased low.J+ = Estimated concentration, biased high.

Location ID

Sample Name

Parent Sample ID

Sample Date

Sample Depth (ft bgs)

U = The analyte was not detected at a level greater than or equal to the adjustedLimit of Detection (LOD).1. Assistant Secretary of Defense. July 2022. Risk-Based Screening Levels inGroundwater and Soil using EPA’s Regional Screening Level Calculator. HazardQuotient (HQ)=0.1. May 2022.2. The Screening Levels for soil are based on a residential scenario for directingestion of contaminated soil.

Values exceeding the Screening Level are shaded gray.

μg/kg = Microgram(s) per kilogramft bgs = Foot (feet) below ground surfaceND = Analyte not detected above the LOD (LOD values are presented in Appendix F).

Qual = Qualifier

Result Qual Result Qual Result Qual Result Qual R

ND U ND U ND U ND U ND U ND U ND U ND U ND U ND U ND U ND U 0ND U ND U 0.29 J ND U 0

1.2 0.32 J 0.29 J 0.79 0

Table 6-2. PFOA, PFOS, PFBS, PFNA, and PFHxS Results in Surface 

Site Inspection Report, AASF #1, Williamstown, West Virginia

AOI01-07 AOI01-08 AOI01-09 AOI01-10 

AOI01-07-HA-0-2 AOI01-08-HA-0-2 AOI01-09-HA-0-2 AOI01-10-HA-0-2 A

2/9/2023 2/9/2023 2/9/2023 2/9/2023 

0-2 0-2 0-2

0-2 

EA Engineering, Science, and Technology, Inc., PBC

AOI = Area of InterestDUP = DuplicateLC/MS/MS = Liquid chromatography/tandem mass spectrometry QSM = Quality Systems Manual 
Site Inspection Report

Williamstown AAFS #1, West Virginia 

Analyte Screening Level1,2

PFAS by LC/MS/MS compliant with QSM Version 5.3 Table B-15 (μg/kg)Perfluorobutanesulfonic acid (PFBS) 1900Perfluorohexanesulfonic acid (PFHxS) 130Perfluorononanoic acid (PFNA) 19Perfluorooctanesulfonic acid (PFOS) 13Perfluorooctanoic acid (PFOA) 19Notes:J = Estimated concentration.J- = Estimated concentration, biased low.J+ = Estimated concentration, biased high.

Location ID

Sample Name

Parent Sample ID

Sample Date

Sample Depth (ft bgs)

U = The analyte was not detected at a level greater than or equal to the adjustedLimit of Detection (LOD).1. Assistant Secretary of Defense. July 2022. Risk-Based Screening Levels inGroundwater and Soil using EPA’s Regional Screening Level Calculator. HazardQuotient (HQ)=0.1. May 2022.2. The Screening Levels for soil are based on a residential scenario for directingestion of contaminated soil.

Values exceeding the Screening Level are shaded gray.

μg/kg = Microgram(s) per kilogramft bgs = Foot (feet) below ground surfaceND = Analyte not detected above the LOD (LOD values are presented in Appendix F).

Qual = Qualifier

Result Qual Result Qual Result Qual Result Q

ND U ND U ND U ND 

3 ND U 0.41 J 2.3 

ND U ND U ND U ND 

73 0.72 1.3 5.4 

0.53 J 0.33 J 1 J+ 1.2 

Table 6-2. PFOA, PFOS, PFBS, PFNA, and PFHxS Results in 

Site Inspection Report, AASF #1, Williamstown, West V

AOI02-03 AOI02-04 AOI02-05 AOI02-0

AOI02-03-SB-0-2 AOI02-04-SB-0-2 AOI02-05-HA-0-2 AOI02-06-H

2/2/2023 2/2/2023 2/6/2023 2/6/2023 

0-2 0-2 0-2 0-2 

EA Engineering, Science, and Technology, Inc., PBC

AOI = Area of InterestDUP = DuplicateLC/MS/MS = Liquid chromatography/tandem mass spectrometry QSM = Quality Systems Manual 
Site Inspection Report

Williamstown AAFS #1, West Virginia 

Analyte Screening Level1,2

PFAS by LC/MS/MS compliant with QSM Version 5.3 Table B-15 (μg/kg)Perfluorobutanesulfonic acid (PFBS) 1900Perfluorohexanesulfonic acid (PFHxS) 130Perfluorononanoic acid (PFNA) 19Perfluorooctanesulfonic acid (PFOS) 13Perfluorooctanoic acid (PFOA) 19Notes:J = Estimated concentration.J- = Estimated concentration, biased low.J+ = Estimated concentration, biased high.

Location ID

Sample Name

Parent Sample ID

Sample Date

Sample Depth (ft bgs)

U = The analyte was not detected at a level greater than or equal to the adjustedLimit of Detection (LOD).1. Assistant Secretary of Defense. July 2022. Risk-Based Screening Levels inGroundwater and Soil using EPA’s Regional Screening Level Calculator. HazardQuotient (HQ)=0.1. May 2022.2. The Screening Levels for soil are based on a residential scenario for directingestion of contaminated soil.

Values exceeding the Screening Level are shaded gray.

μg/kg = Microgram(s) per kilogramft bgs = Foot (feet) below ground surfaceND = Analyte not detected above the LOD (LOD values are presented in Appendix F).

Qual = Qualifier

Result Qual Result Qual Result Qual Result Q

ND U ND U ND U ND ND U ND U ND U ND ND U ND U ND U ND 

0.64 J ND U 0.55 J ND 0.37 J ND U 0.3 J ND 

Table 6-2. PFOA, PFOS, PFBS, PFNA, and PFHxS Results in 

Site Inspection Report, AASF #1, Williamstown, West V

AOI03-01 AOI03-02 WAASF-01 WAASF-

AOI03-01-SB-0-2 AOI03-02-SB-0-2 WAASF-01-SB-0-2 WAASF-02-S

2/3/2023 2/6/2023 2/7/2023 2/7/2023 

0-2 0-2 0-2 0-2 

EA Engineering, Science, and Technology, Inc., PBC

AOI = Area of InterestDUP = DuplicateLC/MS/MS = Liquid chromatography/tandem mass spectrometry QSM = Quality Systems Manual 
Site Inspection Report

Williamstown AAFS #1, West Virginia

Table 6-3. PFOA, PFOS, PFBS, PFNA, and PFHxS Results in Shallow 

Site Inspection Report, AASF #1, Williamstown, West Vi

Analyte Screening Level1,2 Result Qual Result Qual Result 

PFAS by LC/MS/MS compliant with QSM Version 5.3 Table B-15 (μg/kg)Perfluorobutanesulfonic acid (PFBS) 25,000 ND U ND U ND Perfluorohexanesulfonic acid (PFHxS) 1,600 ND U ND U ND Perfluorononanoic acid (PFNA) 250 ND U ND U ND Perfluorooctanesulfonic acid (PFOS) 160 ND U ND U ND Perfluorooctanoic acid (PFOA) 250 ND U ND U ND Notes:J = Estimated concentration.

Location ID AOI01-01 AOI01-02 AOI0

Sample Name AOI01-01-SB-4-5 AOI01-02-SB-14-15 AOI01-03

Parent Sample ID

Sample Date 2/8/2023 2/9/2023 2/9/

Sample Depth (ft bgs) 4-5 14-15 11

U = The analyte was not detected at a level greater than or equal to the adjusted Limit of Detection (LOD).

1. Assistant Secretary of Defense. July 2022. Risk-Based Screening Levels inGroundwater and Soil using EPA’s Regional Screening Level Calculator. HazardQuotient (HQ)=0.1. May 2022.2. The Screening Levels for soil are based on incidental ingestion of soil in aindustrial/commercial worker scenario.

Values exceeding the Screening Level are shaded gray.

μg/kg = Microgram(s) per kilogramft bgs = Foot (feet) below ground surfaceND = Analyte not detected above the LOD (LOD values are presented in Appendix F).Qual = Qualifier

EA Engineering, Science, and Technology, Inc., PBC

AOI = Area of InterestDUP = DuplicateLC/MS/MS = Liquid chromatography/tandem mass spectrometry QSM = Quality Systems Manual 
Site Inspection Report

Williamstown AAFS #1, West Virginia

Analyte Screening Level1,2

PFAS by LC/MS/MS compliant with QSM Version 5.3 Table B-15 (μg/kg)Perfluorobutanesulfonic acid (PFBS) 25,000Perfluorohexanesulfonic acid (PFHxS) 1,600Perfluorononanoic acid (PFNA) 250Perfluorooctanesulfonic acid (PFOS) 160Perfluorooctanoic acid (PFOA) 250Notes:J = Estimated concentration.

Location ID

Sample Name

Parent Sample ID

Sample Date

Sample Depth (ft bgs)

U = The analyte was not detected at a level greater than or equal to the adjusted Limit of Detection (LOD).1. Assistant Secretary of Defense. July 2022. Risk-Based Screening Levels inGroundwater and Soil using EPA’s Regional Screening Level Calculator. HazardQuotient (HQ)=0.1. May 2022.2. The Screening Levels for soil are based on incidental ingestion of soil in aindustrial/commercial worker scenario.

Values exceeding the Screening Level are shaded gray.μg/kg = Microgram(s) per kilogramft bgs = Foot (feet) below ground surfaceND = Analyte not detected above the LOD (LOD values are presented in Appendix F).Qual = Qualifier

Table 6-3. PFOA, PFOS, PFBS, PFNA, and PFHxS Results in Shallo

Site Inspection Report, AASF #1, Williamstown, West Vi

Result Qual Result Qual Result 

ND U ND U 0.84 ND U ND U ND ND U ND U ND ND U ND U ND ND U ND U ND 

AOI02-01 AOI02-02 AOI0

AOI02-01-SB-14-15 AOI02-02-SB-9-10 AOI02-03

2/1/2023 2/2/2023 2/2/

14-15 9-10 9-

EA Engineering, Science, and Technology, Inc., PBC

AOI = Area of InterestDUP = DuplicateLC/MS/MS = Liquid chromatography/tandem mass spectrometry QSM = Quality Systems Manual
Site Inspection Report

Williamstown AAFS #1, West Virginia

Analyte Screening Level1,2

PFAS by LC/MS/MS compliant with QSM Version 5.3 Table B-15 (μg/kg)Perfluorobutanesulfonic acid (PFBS) 25,000Perfluorohexanesulfonic acid (PFHxS) 1,600Perfluorononanoic acid (PFNA) 250Perfluorooctanesulfonic acid (PFOS) 160Perfluorooctanoic acid (PFOA) 250Notes:J = Estimated concentration.

Location ID

Sample Name

Parent Sample ID

Sample Date

Sample Depth (ft bgs)

U = The analyte was not detected at a level greater than or equal to the adjusted Limit of Detection (LOD).1. Assistant Secretary of Defense. July 2022. Risk-Based Screening Levels inGroundwater and Soil using EPA’s Regional Screening Level Calculator. HazardQuotient (HQ)=0.1. May 2022.2. The Screening Levels for soil are based on incidental ingestion of soil in aindustrial/commercial worker scenario.

Values exceeding the Screening Level are shaded gray.μg/kg = Microgram(s) per kilogramft bgs = Foot (feet) below ground surfaceND = Analyte not detected above the LOD (LOD values are presented in Appendix F).Qual = Qualifier

Table 6-3. PFOA, PFOS, PFBS, PFNA, and PFHxS Results in Shal

Site Inspection Report, AASF #1, Williamstown, West V

Result Qual Result Qual Result 

ND U ND U ND ND U ND U ND ND U ND U ND ND U ND U ND 

0.45 J ND U ND 

AOI03-02 WAASF-01 WAA

AOI03-02-SB-9-10 WAASF-01-SB-14-15 WAASF-0

2/7/2023 2/7/2023 2/7/

9-10 14-15 11

EA Engineering, Science, and Technology, Inc., PBC

AOI = Area of InterestDUP = DuplicateLC/MS/MS = Liquid chromatography/tandem mass spectrometry QSM = Quality Systems Manual
Site Inspection Report

Williamstown AASF #1, West Virginia Version: FINAL

EA Engineering, Science, and Technology, Inc., PBC 6-9

This page intentionally left blank 
Site Inspection Report

Williamstown AAFS #1, West Virginia

Table 6-4. PFOA, PFOS, PFBS, PFNA, and PFHxS Results in Deep Subsur

Site Inspection Report, AASF #1, Williamstown, West Virginia

Location ID

Sample Name

Parent Sample ID

Sample Date

Sample Depth (ft bgs)

Analyte Result Qual Result Qual Result 

PFAS by LC/MS/MS compliant with QSM Version 5.3 Table B-15 (μg/kg)Perfluorobutanesulfonic acid (PFBS) ND U ND U ND Perfluorohexanesulfonic acid (PFHxS) ND U ND U ND Perfluorononanoic acid (PFNA) ND U ND U ND Perfluorooctanesulfonic acid (PFOS) ND U ND U ND Perfluorooctanoic acid (PFOA) ND U ND U ND 

Notes:U = The analyte was not detected at a level greater than or equal to the adjusted Limit of Detection (LOD).μg/kg = Microgram(s) per kilogramft bgs = Foot (feet) below ground surfaceND = Analyte not detected above the LOD (LOD values are presented in Appendix F).Qual = Qualifier.

AOI01-02 AOI01-03 AOI0

AOI01-02-SB-28-29 AOI01-03-SB-23-24 AOI02-01

2/9/2023 2/9/2023 2/1/2

28-29 23-24 34

EA Engineering, Science, and Technology, Inc., PBC

AOI = Area of InterestDUP = DuplicateLC/MS/MS = Liquid chromatography/tandem mass spectrometry QSM = Quality Systems Manual
Site Inspection Report

Williamstown AAFS #1, West Virginia

Location ID

Sample Name

Parent Sample ID

Sample Date

Sample Depth (ft bgs)

Analyte

PFAS by LC/MS/MS compliant with QSM Version 5.3 Table B-15 (μg/kg)Perfluorobutanesulfonic acid (PFBS)Perfluorohexanesulfonic acid (PFHxS)Perfluorononanoic acid (PFNA)Perfluorooctanesulfonic acid (PFOS)Perfluorooctanoic acid (PFOA)

Notes:U = The analyte was not detected at a level greater than or equal to the adjusted Limit of Detection (LOD).μg/kg = Microgram(s) per kilogramft bgs = Foot (feet) below ground surfaceND = Analyte not detected above the LOD (LOD values are presented in Appendix F).Qual = Qualifier.

Table 6-4. PFOA, PFOS, PFBS, PFNA, and PFHxS Results in Deep Subsurfa

Site Inspection Report, AASF #1, Williamstown, West Virginia

Result Qual Result Qual Result Qual R

ND U ND U ND U ND U ND U ND U ND U ND U ND U ND U ND U ND U ND U ND U ND U 

AOI02-04 AOI03-01 AOI03-02 

AOI02-04-SB-19-20 AOI03-01-SB-17-18 AOI03-02-SB-19-20 WA

2/2/2023 2/3/2023 2/7/2023 

19-20 17-18 19-20 

EA Engineering, Science, and Technology, Inc., PBC

AOI = Area of InterestDUP = DuplicateLC/MS/MS = Liquid chromatography/tandem mass spectrometry QSM = Quality Systems Manual 
Army National Guard Site Inspections

Site Inspection Report

Williamstown AASF #1, West Virginia

Figure 6-1

AOI 1

PFOS Detections in Soil

WAASF-02

WAASF-01

WAASF-03

AOI01-01

AOI01-05

AOI01-02

AOI01-04

AOI01-03 WAASF-03-HA

AOI01-10-HA

AOI01-09-HA

AOI01-08-HA

AOI01-07-HA

AOI01-06-HA

AOI 1

AOI 2

AOI 3

Burn Pit FTA

Wash Pad FTA

AFFF Storage

WAASF-02

WAASF-01

WAASF-03

AOI01-01

AOI01-05

AOI01-02

AOI01-04

AOI01-03 WAASF-03-HA

AOI 1

AOI 2

AOI 3

Burn Pit FTA

Wash Pad FTA

AFFF Storage

WAASF-02

WAASF-01

WAASF-03

AOI01-02

AOI01-04

AOI01-03 WAASF-03-HA

AOI 1

AOI 2

AOI 3

Burn Pit FTA

Wash Pad FTA

AFFF Storage

3

0 500

Feet

^_

WV

Data Sources:

ESRI 2022

AECOM 2019

Date:....................September 2023

Prepared By:.............................EA

Prepared For:....................USACE

Projection:........WGS 84 UTM 17N

0 500

Feet

0 500

Feet

Shallow Intermediate Deep

Facility Data

Facility Boundary

Area of Interest

Potential PFAS Release

Hydrology

Perennial Creek/Stream

> 1,600

> 160 - 1,600

> 13 - 160

> ND - 13

ND (Non-Detect)

PFOS Results (μg/Kg)

> 1,600

> 160 - 1,600

> 13 - 160

> ND - 13

ND (Non-Detect)

PFOS Results (μg/Kg)

> 1,600

> 160 - 1,600

> 13 - 160

> ND - 13

ND (Non-Detect)

PFOS Results (μg/Kg)

Notes:

PFOS = Perfluorooctanesulfonic acid

Exceedances of the OSD SL are depicted

with a yellow halo. Depth intervals shown

represent respective sampling position

within a given soil boring location.
Site Inspection Report 

Williamstown AASF #1, West Virginia EA Engineering, Science, and Technology, Inc., PBC 

This page intentionally left blank
Figure 6-2

AOI 1

PFOA Detections in Soil

WAASF-02

WAASF-01

WAASF-03

AOI01-01

AOI01-05

AOI01-02

AOI01-04

AOI01-03 WAASF-03-HA

AOI01-10-HA

AOI01-09-HA

AOI01-08-HA

AOI01-07-HA

AOI01-06-HA

AOI 1

AOI 2

AOI 3

Burn Pit FTA

Wash Pad FTA

AFFF Storage

WAASF-02

WAASF-01

WAASF-03

AOI01-01

AOI01-05

AOI01-02

AOI01-04

AOI01-03 WAASF-03-HA

AOI 1

AOI 2

AOI 3

Burn Pit FTA

Wash Pad FTA

AFFF Storage

WAASF-02

WAASF-01

WAASF-03

AOI01-02

AOI01-04

AOI01-03 WAASF-03-HA

AOI 1

AOI 2

AOI 3

Burn Pit FTA

Wash Pad FTA

AFFF Storage

3

0 500

Feet

^_

WV

0 500

Feet

0 500

Feet

Shallow Intermediate Deep

Data Sources:

ESRI 2022

AECOM 2019

> 2,500

> 250 - 2,500

> 19 - 250

> ND - 19

ND (Non-Detect)

PFOA Results (μg/Kg)

> 2,500

> 250- 2,500

> 19 - 250

> ND - 19

ND (Non-Detect)

PFOA Results (μg/Kg)

> 2,500

> 250- 2,500

> 19 - 250

> ND - 19

ND (Non-Detect)

PFOA Results (μg/Kg)

Notes:

PFOA = Perfluorooctanoic acid

Exceedances of the OSD SL are depicted

with a yellow halo. Depth intervals shown

represent respective sampling position

within a given soil boring location.

Army National Guard Site Inspections

Site Inspection Report

Williamstown AASF #1, West Virginia

Date:...................September 2023

Prepared By:.............................EA

Prepared For:....................USACE

Projection:........WGS 84 UTM 17N

Facility Data

Facility Boundary

Area of Interest

Potential PFAS Release

Hydrology

Perennial Creek/Stream
Site Inspection Report 

Williamstown AASF #1, West Virginia EA Engineering, Science, and Technology, Inc., PBC 

This page intentionally left blank
Figure 6-3

AOI 1

PFBS Detections in Soil

WAASF-02

WAASF-01

WAASF-03

AOI01-01

AOI01-05

AOI01-02

AOI01-04

AOI01-03 WAASF-03-HA

AOI01-10-HA

AOI01-09-HA

AOI01-08-HA

AOI01-07-HA

AOI01-06-HA

AOI 1

AOI 2

AOI 3

Burn Pit FTA

Wash Pad FTA

AFFF Storage

WAASF-02

WAASF-01

WAASF-03

AOI01-01

AOI01-05

AOI01-02

AOI01-04

AOI01-03 WAASF-03-HA

AOI 1

AOI 2

AOI 3

Burn Pit FTA

Wash Pad FTA

AFFF Storage

WAASF-02

WAASF-01

WAASF-03

AOI01-02

AOI01-04

AOI01-03 WAASF-03-HA

AOI 1

AOI 2

AOI 3

Burn Pit FTA

Wash Pad FTA

AFFF Storage

3

0 500

Feet

^_

WV

0 500

Feet

0 500

Feet

Shallow Intermediate Deep

Data Sources:

ESRI 2022

AECOM 2019

> 25,000

> 1,900 - 25,000

> 10 - 1,900

> ND - 10

ND (Non-Detect)

PFBS Results (μg/Kg)

> 25,000

> 1,900 - 25,000

> 10 - 1,900

> ND - 10

ND (Non-Detect)

PFBS Results (μg/Kg)

> 25,000

> 1,900 - 25,000

> 10 - 1,900

> ND - 10

ND (Non-Detect)

PFBS Results (μg/Kg)

Notes:

PFOS = Perfluorooctanesulfonic acid Exceedances of the OSD 

SL are depicted with a yellow halo. Depth intervals shown 

represent respective sampling position within a given soil boring 

location.

*Results for AOI2 and AOI3 are discussed on Figures 6-6

through 6-10

Army National Guard Site Inspections

Site Inspection Report

Williamstown AASF #1, West Virginia

Facility Data

Facility Boundary

Area of Interest

Potential PFAS Release

Hydrology

Perennial Creek/Stream

Date:.....................September 2023

Prepared By:.............................EA

Prepared For:....................USACE

Projection:........WGS 84 UTM 17N
Site Inspection Report 

Williamstown AASF #1, West Virginia EA Engineering, Science, and Technology, Inc., PBC 

This page intentionally left blank
Figure 6-3

AOI 1

PFBS Detections in Soil

WAASF-02

WAASF-01

WAASF-03

AOI01-01

AOI01-05

AOI01-02

AOI01-04

AOI01-03 WAASF-03-HA

AOI01-10-HA

AOI01-09-HA

AOI01-08-HA

AOI01-07-HA

AOI01-06-HA

AOI 1

AOI 2

AOI 3

Burn Pit FTA

Wash Pad FTA

AFFF Storage

WAASF-02

WAASF-01

WAASF-03

AOI01-01

AOI01-05

AOI01-02

AOI01-04

AOI01-03 WAASF-03-HA

AOI 1

AOI 2

AOI 3

Burn Pit FTA

Wash Pad FTA

AFFF Storage

WAASF-02

WAASF-01

WAASF-03

AOI01-02

AOI01-04

AOI01-03 WAASF-03-HA

AOI 1

AOI 2

AOI 3

Burn Pit FTA

Wash Pad FTA

AFFF Storage

3

0 500

Feet

^_

WV

0 500

Feet

0 500

Feet

Shallow Intermediate Deep

Data Sources:

ESRI 2022

AECOM 2019

> 25,000

> 1,900 - 25,000

> 10 - 1,900

> ND - 10

ND (Non-Detect)

PFBS Results (μg/Kg)

> 25,000

> 1,900 - 25,000

> 10 - 1,900

> ND - 10

ND (Non-Detect)

PFBS Results (μg/Kg)

> 25,000

> 1,900 - 25,000

> 10 - 1,900

> ND - 10

ND (Non-Detect)

PFBS Results (μg/Kg)

Notes:

PFBS = Perfluorobutanesulfonic acid

Exceedances of the OSD SL are depicted

with a yellow halo. Depth intervals shown

represent respective sampling position

within a given soil boring location.

Army National Guard Site Inspections

Site Inspection Report

Williamstown AASF #1, West Virginia

Facility Data

Facility Boundary

Area of Interest

Potential PFAS Release

Hydrology

Perennial Creek/Stream

Date:.....................September 2023

Prepared By:.............................EA

Prepared For:....................USACE

Projection:........WGS 84 UTM 17N
Site Inspection Report 

Williamstown AASF #1, West Virginia EA Engineering, Science, and Technology, Inc., PBC 

1077 This page intentionally left blank 
Figure 6-4

AOI 1

PFHxS Detections in Soil

WAASF-02

WAASF-01

WAASF-03

AOI01-01

AOI01-05

AOI01-02

AOI01-04

AOI01-03 WAASF-03-HA

AOI01-10-HA

AOI01-09-HA

AOI01-08-HA

AOI01-07-HA

AOI01-06-HA

AOI 1

AOI 2

AOI 3

Burn Pit FTA

Wash Pad FTA

AFFF Storage

WAASF-02

WAASF-01

WAASF-03

AOI01-01

AOI01-05

AOI01-02

AOI01-04

AOI01-03 WAASF-03-HA

AOI 1

AOI 2

AOI 3

Burn Pit FTA

Wash Pad FTA

AFFF Storage

WAASF-02

WAASF-01

WAASF-03

AOI01-02

AOI01-04

AOI01-03 WAASF-03-HA

AOI 1

AOI 2

AOI 3

Burn Pit FTA

Wash Pad FTA

AFFF Storage

3

0 500

Feet

^_

WV

Data Sources:

ESRI 2022

AECOM 2019

0 500

Feet

0 500

Feet

Shallow Intermediate Deep

> 1,600

> 130 - 1,600

> 10 - 130

> ND - 10

ND (Non-Detect)

PFHxS Result (μg/Kg)

> 1,600

> 130 - 1,600

> 10 - 130

> ND - 10

ND (Non-Detect)

PFHxS Result (μg/Kg)

Notes:

PFHxS = Perfluorohexanesulfonic acid

Exceedances of the OSD SL are depicted

with a yellow halo. Depth intervals shown

represent respective sampling position

within a given soil boring location.

> 1,600

> 130 - 1,600

> 10 - 130

> ND - 10

ND (Non-Detect)

PFHxS Result (μg/Kg)

Army National Guard Site Inspections

Site Inspection Report

Williamstown AASF #1, West Virginia

Date:.....................September 2023

Prepared By:.............................EA

Prepared For:....................USACE

Projection:........WGS 84 UTM 17N

Facility Data

Facility Boundary

Area of Interest

Potential PFAS Release

Hydrology

Perennial Creek/Stream
Site Inspection Report 

Williamstown AASF #1, West Virginia EA Engineering, Science, and Technology, Inc., PBC 

This page intentionally left blank 
Army National Guard Site Inspections

Site Inspection Report

Williamstown AASF #1, West Virginia

Figure 6-6

AOI 2 and AOI 3

PFOS Detections in Soil

AOI02-04

AOI02-03

AOI02-01

AOI02-02

AOI03-02

AOI03-01

AOI02-01-HA

AOI02-08-HA

AOI02-07-HA

AOI02-06-HA AOI02-05-HA

AOI 2

AOI 3

AFFF Storage Wash Pad FTA

AOI02-04

AOI02-03

AOI02-01

AOI02-02

AOI03-02

AOI03-01

AOI02-01-HA

AOI 2

AOI 3

AFFF Storage Wash Pad FTA

AOI02-04

AOI02-03

AOI02-01

AOI02-02

AOI03-02

AOI03-01

AOI02-01-HA

AOI 2

AOI 3

AFFF Storage Wash Pad FTA

3

0 100

Feet

^_

WV

Data Sources:

ESRI 2022

AECOM 2019

Date:......................September 2023

Prepared By:.............................EA

Prepared For:....................USACE

Projection:........WGS 84 UTM 17N

0 100

Feet

0 100

Feet

Shallow Intermediate Deep

Facility Data

Facility Boundary

Area of Interest

Potential PFAS Release

Hydrology

Perennial Creek/Stream

> 1,600

> 160 - 1,600

> 13 - 160

> ND - 13

ND (Non-Detect)

PFOS Results (μg/Kg)

> 1,600

> 160 - 1,600

> 13 - 160

> ND - 13

ND (Non-Detect)

PFOS Results (μg/Kg)

> 1,600

> 160 - 1,600

> 13 - 160

> ND - 13

ND (Non-Detect)

PFOS Results (μg/Kg)

Notes:

PFOS = Perfluorooctanesulfonic acid

Exceedances of the OSD SL are depicted

with a yellow halo. Depth intervals shown

represent respective sampling position

within a given soil boring location.
Site Inspection Report 

Williamstown AASF #1, West Virginia EA Engineering, Science, and Technology, Inc., PBC 

This page intentionally left blank
Figure 6-7

AOI 2 and AOI 3

PFOA Detections in Soil

AOI02-04

AOI02-03

AOI02-01

AOI02-02

AOI03-02

AOI03-01

AOI02-01-HA

AOI02-08-HA

AOI02-07-HA

AOI02-06-HA AOI02-05-HA

AOI 2

AOI 3

AFFF Storage Wash Pad FTA

AOI02-04

AOI02-03

AOI02-01

AOI02-02

AOI03-02

AOI03-01

AOI02-01-HA

AOI 2

AOI 3

AFFF Storage Wash Pad FTA

AOI02-04

AOI02-03

AOI02-01

AOI02-02

AOI03-02

AOI03-01

AOI02-01-HA

AOI 2

AOI 3

AFFF Storage Wash Pad FTA

3

0 100

Feet

^_

WV

0 100

Feet

0 100

Feet

Shallow Intermediate Deep

Data Sources:

ESRI 2022

AECOM 2019

> 2,500

> 250 - 2,500

> 19 - 250

> ND - 19

ND (Non-Detect)

PFOA Results (μg/Kg)

> 2,500

> 250- 2,500

> 19 - 250

> ND - 19

ND (Non-Detect)

PFOA Results (μg/Kg)

> 2,500

> 250- 2,500

> 19 - 250

> ND - 19

ND (Non-Detect)

PFOA Results (μg/Kg)

Notes:

PFOA = Perfluorooctanoic acid

Exceedances of the OSD SL are depicted

with a yellow halo. Depth intervals shown

represent respective sampling position

within a given soil boring location.

Army National Guard Site Inspections

Site Inspection Report

Williamstown AASF #1, West Virginia

Date:.................... September 2023

Prepared By:.............................EA

Prepared For:....................USACE

Projection:........WGS 84 UTM 17N

Facility Data

Facility Boundary

Area of Interest

Potential PFAS Release

Hydrology

Perennial Creek/Stream
Site Inspection Report 

Williamstown AASF #1, West Virginia EA Engineering, Science, and Technology, Inc., PBC 

This page intentionally left blank
Figure 6-8

AOI 2 and AOI 3

PFBS Detections in Soil

AOI02-04

AOI02-03

AOI02-01

AOI02-02

AOI03-02

AOI03-01

AOI02-01-HA

AOI02-08-HA

AOI02-07-HA

AOI02-06-HA AOI02-05-HA

AOI 2

AOI 3

AFFF Storage Wash Pad FTA

AOI02-04

AOI02-03

AOI02-01

AOI02-02

AOI03-02

AOI03-01

AOI02-01-HA

AOI 2

AOI 3

AFFF Storage Wash Pad FTA

AOI02-04

AOI02-03

AOI02-01

AOI02-02

AOI03-02

AOI03-01

AOI02-01-HA

AOI 2

AOI 3

AFFF Storage Wash Pad FTA

3

0 100

Feet

^_

WV

0 100

Feet

0 100

Feet

Shallow Intermediate Deep

Data Sources:

ESRI 2022

AECOM 2019

> 25,000

> 1,900 - 25,000

> 10 - 1,900

> ND - 10

ND (Non-Detect)

PFBS Results (μg/Kg)

> 25,000

> 1,900 - 25,000

> 10 - 1,900

> ND - 10

ND (Non-Detect)

PFBS Results (μg/Kg)

> 25,000

> 1,900 - 25,000

> 10 - 1,900

> ND - 10

ND (Non-Detect)

PFBS Results (μg/Kg)

Notes:

PFBS = Perfluorobutanesulfonic acid

Exceedances of the OSD SL are depicted

with a yellow halo. Depth intervals shown

represent respective sampling position

within a given soil boring location.

Army National Guard Site Inspections

Site Inspection Report

Williamstown AASF #1, West Virginia

Date:.....................September 2023

Prepared By:.............................EA

Prepared For:....................USACE

Projection:........WGS 84 UTM 17N

Facility Data

Facility Boundary

Area of Interest

Potential PFAS Release

Hydrology

Perennial Creek/Stream
Site Inspection Report 

Williamstown AASF #1, West Virginia EA Engineering, Science, and Technology, Inc., PBC 

This page intentionally left blank
Figure 6-9

AOI 2 and AOI 3

PFHxS Detections in Soil

AOI02-04

AOI02-03

AOI02-01

AOI02-02

AOI03-02

AOI03-01

AOI02-01-HA

AOI02-08-HA

AOI02-07-HA

AOI02-06-HA AOI02-05-HA

AOI 2

AOI 3

AFFF Storage Wash Pad FTA

AOI02-04

AOI02-03

AOI02-01

AOI02-02

AOI03-02

AOI03-01

AOI02-01-HA

AOI 2

AOI 3

AFFF Storage Wash Pad FTA

AOI02-04

AOI02-03

AOI02-01

AOI02-02

AOI03-02

AOI03-01

AOI02-01-HA

AOI 2

AOI 3

AFFF Storage Wash Pad FTA

3

0 100

Feet

^_

WV

Data Sources:

ESRI 2022

AECOM 2019

0 100

Feet

0 100

Feet

Shallow Intermediate Deep

> 1,600

> 130 - 1,600

> 10 - 130

> ND - 10

ND (Non-Detect)

PFHxS Result (μg/Kg)

> 1,600

> 130 - 1,600

> 10 - 130

> ND - 10

ND (Non-Detect)

PFHxS Result (μg/Kg)

Notes:

PFHxS = Perfluorohexanesulfonic acid

Exceedances of the OSD SL are depicted

with a yellow halo. Depth intervals shown

represent respective sampling position

within a given soil boring location.

> 1,600

> 130 - 1,600

> 10 - 130

> ND - 10

ND (Non-Detect)

PFHxS Result (μg/Kg)

Army National Guard Site Inspections

Site Inspection Report

Williamstown AASF #1, West Virginia

Date:...................September 2023

Prepared By:.............................EA

Prepared For:....................USACE

Projection:........WGS 84 UTM 17N

Facility Data

Facility Boundary

Area of Interest

Potential PFAS Release

Hydrology

Perennial Creek/Stream
Site Inspection Report 

Williamstown AASF #1, West Virginia EA Engineering, Science, and Technology, Inc., PBC 

This page intentionally left blank
Figure 6-10

AOI 2 and AOI 3

PFNA Detections in Soil

AOI02-04

AOI02-03

AOI02-01

AOI02-02

AOI03-02

AOI03-01

AOI02-01-HA

AOI02-08-HA

AOI02-07-HA

AOI02-06-HA AOI02-05-HA

AOI 2

AOI 3

AFFF Storage Wash Pad FTA

AOI02-04

AOI02-03

AOI02-01

AOI02-02

AOI03-02

AOI03-01

AOI02-01-HA

AOI 2

AOI 3

AFFF Storage Wash Pad FTA

AOI02-04

AOI02-03

AOI02-01

AOI02-02

AOI03-02

AOI03-01

AOI02-01-HA

AOI 2

AOI 3

AFFF Storage Wash Pad FTA

3

0 100

Feet

^_

WV

Data Sources:

ESRI 2022

AECOM 2019

0 100

Feet

0 100

Feet

Shallow Intermediate Deep

> 2,500

> 250 - 2,500

> 19 - 250

> ND - 19

ND (Non-Detect)

PFNA Results (μg/Kg)

> 2 ,500

> 250 - 2,500

> 19 - 250

> ND - 19

ND (Non-Detect)

PFNA Results (μg/Kg)

> 2 ,500

> 250 - 2,500

> 19 - 250

> ND - 19

ND (Non-Detect)

PFNA Results (μg/Kg)

Notes:

PFNA = Perfluorononanoic acid

Exceedances of the OSD SL are depicted

with a yellow halo. Depth intervals shown

represent respective sampling position

within a given soil boring location.

Army National Guard Site Inspections

Site Inspection Report

Williamstown AASF #1, West Virginia

Facility Data

Facility Boundary

Area of Interest

Potential PFAS Release

Hydrology

Perennial Creek/Stream

Date:....................September 2023

Prepared By:.............................EA

Prepared For:....................USACE

Projection:........WGS 84 UTM 17N
Site Inspection Report 

Williamstown AASF #1, West Virginia Version: FINAL 

EA Engineering, Science, and Technology, Inc., PBC 6-2

This page intentionally left blank
Site Inspection Report 

Williamstown AASF #1, West Virginia Version: FINAL 

EA Engineering, Science, and Technology, Inc., PBC 7-1

7. EXPOSURE PATHWAYS

CSMs for the AOIs, revised based on the SI findings, are presented on Figure 7-1 through 

Figure 7-3. Please note that while the CSM discussions assists in determining if a receptor may 

be impacted, the decision to move from SI to RI or interim action is determined based upon 

exceedances of the SLs for the relevant compounds and whether the release is more than likely 

attributable to the DoD. A CSM presents the current understanding of the site conditions with 

respect to known and suspected sources, potential transport mechanisms and migration 

pathways, and potentially exposed human receptors. A human exposure pathway is considered 

potentially complete when the following conditions are present: 

1. Contaminant source

2. Environmental fate and transport

3. Exposure point

4. Exposure route

5. Potentially exposed populations.

If any of these elements are missing, the pathway is incomplete. The CSM figures use an empty 

circle symbol to represent an incomplete exposure pathway. Areas with no identified complete 

pathway generally warrant no further action. However, the pathway is considered potentially 

complete if the relevant compounds are detected, in which case the CSM figure uses a half-filled 

circle symbol to represent a potentially complete exposure pathway. Additionally, a completely 

filled circle symbol is used to indicate when a potentially complete exposure pathway has 

detections of relevant compounds above the SLs. Areas with an identified potentially complete 

pathway that have detections of the relevant compounds above the SLs may warrant further 

investigation. Although the CSMs indicate whether potentially complete exposure pathways may 

exist, the recommendation for future study in a RI or no action at this time is based on the 

comparison of the SI analytical results for the relevant compounds to the SLs. 

In general, the potential routes of exposure to the relevant compounds are ingestion and 

inhalation. Human exposure via the dermal contact pathway may occur, and current risk practice 

suggests it is an insignificant pathway compared to ingestion; however, exposure data for dermal 

pathways are sparse and continue to be the subject of toxicological study. The receptors 

evaluated are consistent with those listed in USEPA guidance for risk screening (USEPA 2001). 

Receptors at the Facility include site workers (e.g., staff and visiting soldiers), future 

construction workers, trespassers (though unlikely due to restricted access), off-Facility 

recreational users, and residents. 

7.1 SOIL EXPOSURE PATHWAY 

The SI results for soil were used to determine whether a potentially complete pathway exists 

between the source and potential receptors at each AOI (AOIs 1 through 3) based on the 

aforementioned criteria. Due to its’ location with respect to AOI 2 and AOI 3, AOI 1 will be 

treated as a singular CSM. AOIs 2 and 3 are co-located within 300ft of each other, but due to 

different surface water flow directions, as well as an exceedance in AOI 2 and not in AOI 3, 

AOIs 2 and 3 will also be treated as separate CSMs. 
Site Inspection Report 

Williamstown AASF #1, West Virginia Version: FINAL 

EA Engineering, Science, and Technology, Inc., PBC 7-2

7.1.1 AOI 1 

AOI 1 is the Burn Pit FTA, located on the central-eastern side of the Facility. The Burn Pit FTA 

was once located on an unpaved stretch of land near the large concrete pad where AFFF was 

released directly to the surface soil around the pit. Facility personnel interviewed noted that the 

adjacent Airport Fire Department was permitted to conduct a singular fire training exercise at 

this location, where the fire department used their firetruck equipped with an unknown AFFF 

agent to extinguish flames at an undocumented time period. 

PFOA and PFOS were detected in surface soils associated with nine of the ten boring locations at 

concentrations below their respective SLs. Site workers and future construction workers could 

contact constituents in surface soil via incidental ingestion and inhalation of dust. Therefore, the 

surface soil exposure pathways for site workers and future construction workers are considered 

potentially complete. There was a single detection for PFOA in the shallow subsurface sample at 

AOI01-05, below the SL for shallow subsurface soils, roughly 6ft below grade. Ground 

disturbing activities in this location could result in incidental ingestion for future construction 

workers. Therefore, the exposure pathways for subsurface soil are considered potentially 

complete for the future construction worker. The CSM is presented on 

Figure 7-1. 

7.1.2 AOI 2 

AOI 2 is the Wash Pad FTA, located in the central portion of the Facility, roughly 300 ft slightly 

southeast of the AFFF Storage (AOI 3). Prior to 2006, AFFF released to the concrete wash pad 

during annual fire training activities was rinsed down the wash pad drain with water, which 

flowed south through pipes into the OWS, then flowed out through an outfall at the facility 

boundary and towards Big Run River. After 2006, a restructured tank with a valve directing 

water to the Williamstown Wastewater Treatment Plant was installed and used during fire 

training activities. The potential exists for the valve to have accidentally not been used during 

trainings and for overflow to continue to flow out the outfall at the property boundary, although 

no documentation exists for this occurring. 

PFOA, PFOS, PFNA, and PFHxS were detected in AOI 2 surface soils. PFOA, PFNA, and 

PFHxS were detected in surface soils at concentrations below their respective SLs. PFOS was 

detected below and above the SL, with a single exceedance at AOI02-03. The downgradient 

boundary location at the OWS outflow, WAASF-03 and the additional hand auger sample 

WAASF-03-HA, also had detections of PFOA below the SL. Site workers and future 

construction workers could contact constituents in surface soil via incidental ingestion and 

inhalation of dust. Therefore, the surface soil exposure pathways for site workers and future 

construction workers are potentially complete. A single detection for PFBS below the SL 

occurred in AOI 2 shallow subsurface soil roughly 10 ft below grade, with no other relevant 

compounds detected in shallow or deep subsurface soils at AOI 2 or the boundary location. 

Although unlikely, ground disturbing activities in AOI 2 could result in incidental ingestion for 

future construction workers. Therefore, the exposure pathways for subsurface soil are considered 

potentially complete for the future construction worker. The CSM is presented in Figure 7-2. 
Site Inspection Report 

Williamstown AASF #1, West Virginia Version: FINAL 

EA Engineering, Science, and Technology, Inc., PBC 7-3

7.1.3 AOI 3 

AOI 3 is the Materials Storage Room, or AFFF Storage, previously used to store 5-gallon 

buckets of AFFF of an unknown concentration. No record or documentation exists of spills or 

leaks at this location. 

PFOA and PFOS were detected in surface soils at AOI 3 at concentrations below their respective 

SLs. Site workers and future construction workers could contact constituents in surface soil via 

incidental ingestion and inhalation of dust. Therefore, the surface soil exposure pathways for site 

and future construction workers are considered potentially complete. There was a single 

detection of PFOA below the SL in shallow subsurface between 9 and 10 ft bgs. There were no 

deep subsurface detections in soil. Future construction workers could contact constituents in 

shallow subsurface soil through ground disturbing activities. Therefore, the exposure pathways 

for subsurface soil are considered potentially complete for future construction workers. The 

CSM is presented in Figure 7-3.

7.2 GROUNDWATER EXPOSURE PATHWAY 

The SI results for groundwater are used to determine whether a potentially complete pathway 

exists between the source and potential receptors based on the aforementioned criteria. However, 

shallow groundwater was not encountered, and no temporary wells were installed at any AOI or 

boundary location; therefore, no grab groundwater samples were collected or analyzed. This 

pathway is considered incomplete. 

7.3 SURFACE WATER AND SEDIMENT EXPOSURE PATHWAY 

Off-Facility surface water and sediment were not sampled as part of this SI, as the scope of 

sampling was limited to the presence or absence of the relevant compounds in soil and 

groundwater within the facility boundary. Although no surface water features flow through 

Williamstown AASF #1, the Facility sits on a topographic high with the ground sloping steeply 

off-facility between the southwestern to northwestern boundary in the direction of presumed 

groundwater flow and observed surface water flow direction. Big Run, a tributary to the Ohio 

River, is roughly 1,500 ft southwest of boundary location WAASF-03 and the outfall from the 

AOI 2 OWS. Further, Plum Run, which connects to Big Run and then the Ohio River, is roughly 

200 ft north of boundary location WAASF-02 (which is upgradient to all AOIs), and roughly 

1700ft north of WAASF-01 (which is upgradient of AOIs 2 and 3). The Ohio River, as well as 

tributaries it connects to, continue north downgradient and are high-use bodies of water for 

fishing, swimming, boating, and are a source for groundwater. The detections of relevant 

compounds seen in surface soil at WAASF-03 and AOI 2 (with an exceedance for PFOS) lends 

credence to surface water and sediment being transferred out and away as runoff via topography 

and the OWS outfall and off the Facility property. No detections were observed in WAASF-02; 

however, this is likely, as surface water and sediment runoff from AOI 3 would flow off-site near 

WAASF-01, due to its proximity and the topographic gradient between AOI 3 and WAASF-01. 

Indeed, surface soil detections in AOI 3 and WAASF-01 corroborate this. Further, the extensive 

clayey-silty soils, weathered bedrock, and lack of a shallow groundwater unit observed 

throughout the entire Facility could also contribute to slow infiltration rates, high storability, and 

surface runoff events with soils comprised of PFAS relevant compounds. Due to this, and the 
Site Inspection Report 

Williamstown AASF #1, West Virginia Version: FINAL 

EA Engineering, Science, and Technology, Inc., PBC 7-4

potential for PFAS relevant compounds to discharge to nearby tributaries of the Ohio River, the 

ingestion exposure pathway for surface water and sediment is considered potentially complete 

for site and future construction workers, trespassers, and off-Facility recreational users and 

residents who use the downgradient water bodies. The CSMs are presented on Figures 7-1 

through 7-3. 
SOURCE

Source Release 

Mechanism Media

RECEPTOR

Human 

Activities

Leaching/

Infiltration

Airborne Soil 

Particulate

Surface Soil

Surface 

Water/ 

Sediment

Subsurface 

Soil

PATHWAY

Transport 

and Migration Media Exposure Routes

Inhalation of

Dust

Human Receptors: 

Current/ Future

Site

Worker

Site

Worker

Construction Resident2,3

Worker1

/ /

/

Construction Resident2,3

Worker 1

/ / /

/ /

Figure 7-1

Conceptual Site Model

AOI 1 Williamstown AASF #1 

/ /

/

/

Williamstown 

AASF #1 

AOI 1

Precipitation/ 

Run-Off

Ingestion

Trespasser/

Recreational User2,3

Trespasser/

Recreational User2,3

/ / / /

Ingestion

Ingestion

Ingestion

/

Surface 

Water 

Flow

Surface 

Soil

Subsurface 

Soil

Potential AFFF 

Release

Surface 

Water

Shallow 

Groundwater

Potential

Off-Facility

Sources Not

Under

Control of

ARNG

/ / / /

Potentially Complete Pathway 

with Exceedance of Screening 

Level

LEGEND

Flow Chart Stops

Flow Chart Continues

Partial/ Possible Flow

Incomplete Pathway

Partially Complete Pathway

Notes:

1. No current/active construction at the site.

2. The resident and recreational users refer to offsite receptors.
Site Inspection Report 

Williamstown AASF #1, West Virginia EA Engineering, Science, and Technology, Inc., PBC 

This page intentionally left blank
SOURCE

Source Release 

Mechanism Media

RECEPTOR

Human 

Activities

Leaching/

Infiltration

Airborne Soil 

Particulate

Surface Soil

Surface 

Water/ 

Sediment

Subsurface 

Soil

PATHWAY

Transport 

and Migration Media Exposure Routes

Inhalation of

Dust

Human Receptors: 

Current/ Future

Site

Worker

Site

Worker

Construction Resident2,3

Worker1

/ /

/

Construction Resident2,3

Worker 1

/ / /

/ /

Figure 7-2

Conceptual Site Model

AOI 2 Williamstown AASF #1 

/ /

/

/

Williamstown 

AASF #1 

AOI 2

Precipitation/ 

Run-Off

Ingestion

Trespasser/

Recreational User2,3

Trespasser/

Recreational User2,3

/ / / /

Ingestion

Ingestion

Ingestion

/

Surface 

Water 

Flow

Surface 

Soil

Subsurface 

Soil

Potential AFFF 

Release

Surface 

Water

Shallow 

Groundwater

Potential

Off-Facility

Sources Not

Under

Control of

ARNG

/ / / /

Potentially Complete Pathway 

with Exceedance of Screening 

Level

LEGEND

Flow Chart Stops

Flow Chart Continues

Partial/ Possible Flow

Incomplete Pathway

Partially Complete Pathway

Notes:

1. No current/active construction at the site.

2. The resident and recreational users refer to

off-site receptors.
Site Inspection Report 

Williamstown AASF #1, West Virginia EA Engineering, Science, and Technology, Inc., PBC 

This page intentionally left blank
SOURCE

Source Release 

Mechanism Media

RECEPTOR

Human 

Activities

Leaching/

Infiltration

Airborne Soil 

Particulate

Surface Soil

Surface 

Water/ 

Sediment

Subsurface 

Soil

PATHWAY

Transport 

and Migration Media Exposure Routes

Inhalation of

Dust

Human Receptors: 

Current/ Future

Site

Worker

Site

Worker

Construction Resident2,3

Worker1

/ /

/

Construction Resident2,3

Worker 1

/ / /

/ /

Figure 7-3

Conceptual Site Model

AOI 3 Williamstown AASF #1 

/ /

/

/

Williamstown 

AASF #1 

AOI 3

Precipitation/ 

Run-Off

Ingestion

Trespasser/

Recreational User2,3

Trespasser/

Recreational User2,3

/ / / /

Ingestion

Ingestion

Ingestion

/

Surface 

Water 

Flow

Surface 

Soil

Subsurface 

Soil

Potential AFFF 

Release

Surface 

Water

Shallow 

Groundwater

Potential

Off-Facility

Sources Not

Under

Control of

ARNG

/ / / /

Potentially Complete Pathway 

with Exceedance of Screening 

Level

LEGEND

Flow Chart Stops

Flow Chart Continues

Partial/ Possible Flow

Incomplete Pathway

Partially Complete Pathway

Notes:

1. No current/active construction at the site.

2. The resident and recreational users refer to offsite receptors.
Site Inspection Report 

Williamstown AASF #1, West Virginia EA Engineering, Science, and Technology, Inc., PBC 

This page intentionally left blank
Site Inspection Report 

Williamstown AASF #1, West Virginia Version: FINAL 

EA Engineering, Science, and Technology, Inc., PBC 8-1

8. SUMMARY AND OUTCOME

This section summarizes SI activities and findings. The most significant findings are summarized 

in this section and are reproduced directly or abstracted from information contained in this 

report. The outcome provides general and comparative interpretations of the findings relative to 

the SLs. 

8.1 SITE INSPECTION ACTIVITIES 

The SI field activities were conducted from 31 January to 9 February 2023 and consisted of 

Sonic drilling and hand auger borings and soil sample collection. Field activities were conducted 

in accordance with the UFP-QAPP Addendum (EA 2022), except as noted in Section 5.9. 

To fulfill the project DQOs set forth in the approved SI UFP-QAPP Addendum (EA 2022), 

samples were collected and analyzed for a subset of PFAS by LC/MS/MS compliant with QSM 

Version 5.3 Table B-15 as follows: 

 Fifty-Two (52) soil samples from 14 primary locations, 9 secondary (hand auger)

locations, and 3 boundary locations

 Twenty (20) quality assurance/quality control samples.

An SI is conducted when the PA determines an AOI exists based on probable use, storage, and/or 

disposal of PFAS-containing materials. The SI includes multi-media sampling at AOIs to 

determine whether or not a release has occurred. The SI may conclude further investigation is 

warranted, a removal action is required to address immediate threats, or NFA is required. 

Additionally, the CSMs were refined to assess whether a potentially complete pathway exists 

between the source and potential receptors for potential exposure at the AOIs, which are 

described in Section 7. 

8.2 OUTCOME 

Based on the results of this SI, further evaluation RI is warranted for AOI 2. Based on the 

CSMs developed and revised on the SI findings, there is potential for exposure to off-Facility 

residential drinking water receptors, surface water recreators, and on-site future construction and 

site workers from releases during historical DoD activities at the Facility. Sample chemical 

analytical concentrations collected during this SI were compared against the project SLs in soil 

as described in Table 6-1. 

A summary of the results of the SI data relative to SLs is as follows: 

 AOI 1:

 No groundwater samples were collected or analyzed at AOI 1. 
Site Inspection Report 

Williamstown AASF #1, West Virginia Version: FINAL 

EA Engineering, Science, and Technology, Inc., PBC 8-2

 PFOA was detected in surface soil at AOI 1, with a single detection in subsurface 

soil. No other relevant compounds were detected. Based on the results of this SI, 

NFA is warranted for AOI 1. 

 AOI 2:

 No groundwater samples were collected or analyzed at AOI 2. 

 PFOA, PFNA, and PFHxS were detected in surface soil at AOI 2 at 

concentrations below their respective SLs. PFOS was also detected in surface soil, 

with an exceedance of the SL observed at one location. PFBS was detected in a 

single location in shallow subsurface soil below the SL. There were no other 

detections for relevant compounds in shallow or deep subsurface soil. Based on 

the results of this SI, further action for AOI 2 is warranted in the RI. 

 AOI 3:

 No groundwater samples were collected or analyzed at AOI 3. 

 PFOA and PFOS were detected at concentrations below their respective SLs in 

surface soil, with a single PFOA detection in shallow subsurface soil below the 

SL. There were no other detections of relevant compounds at AOI 3. Based on the 

results of this SI, no further action is warranted for AOI 3. 

 Facility Boundary:

 No groundwater samples were collected or analyzed at the Facility Boundaries. 

 PFOA and PFOS were detected in surface soil at the Facility Boundary at 

concentrations below their respective SLs. There were no detections of relevant 

compounds in shallow or deep subsurface soil. 

Of the six PFAS compounds presented in the 6 July 2022 OSD memorandum, HFPO-DA 

(commonly referred to as GenX) was not included as an analyte at the time of this SI. Based on 

the CSM developed during the PA and revised based on SI findings, the presence of HFPO-DA 

is not anticipated at the facility because HFPO-DA is generally not a component MIL-SPEC 

AFFF and based on its history including distribution limitations that restricted use of GenX, it is 

generally not a component of other products the military used. In addition, it is unlikely that 

GenX would be an individual chemical of concern in the absence of other PFAS. 

Table 8-1 summarizes the SI results for soil and groundwater used to determine if an AOI should 

be considered for further investigation under CERCLA and undergo an RI. 
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Table 8-1. Summary of Site Inspection Findings and Recommendations 

AOI 

Potential Release 

Area

Soil 

Source Area

Groundwater 

Source Area

Groundwater 

Facility Boundary Future Action 

1 Burn Pit FTA NA NA NFA 

2 Wash Pad FTA NA NA Proceed to RI 

3 AFFF Storage NA NA NFA 

Legend: 

 = Detected; exceedance of SLs 

 = Detected; no exceedance of SLs 

 = Not detected 
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9. REFERENCES

AECOM Technical Services, Inc. (AECOM). 2020. Final Preliminary Assessment Report, Army 

Aviation Support Facility #1, Williamstown, West Virginia. July. 

Assistant Secretary of Defense. 2022. Investigation Per- and Polyfluoroalkyl Substances within 

The Department of Defense Cleanup Program. United States Department of Defense. 6 

July. 

Department of the Army. 2016. EM-200-1-2, Environmental Quality, Technical Project 

Planning Process. 29 February. 

Department of Defense (DoD). 2019a. General Data Validation Guidelines. November. 

———. 2019b. Department of Defense (DoD), Department of Energy (DOE) Consolidated 

Quality Systems Manual (QSM) for Environmental Laboratories, Version 5.3. May. 

. 2020. Data Validation Guidelines Module 3: Data Validation Procedure for Per- and 

Polyfluoroalkyl Substances Analysis by QSM Table B-15. May. 

EA, Engineering, Science, and Technology, PBC (EA). 2020a. Final Programmatic Uniform 

Federal Policy Quality Assurance Project Plan, Site Inspections for Per- and 

Polyfluoroalkyl Substances Impacted Sites, ARNG Installations, Nationwide. December. 

. 2020b. Programmatic Accident Prevention Plan, Revision 1, November 2020. 

. 2021. Final Accident Prevention Plan Site Safety and Health Plan, Army Aviation 

Support Facility #1, Williamstown, West Virginia Revision 0, October 2021. 

. 2022. Final Site Inspection Uniform Federal Policy Quality Assurance Project Plan 

(UFP-QAPP) Addendum Army Aviation Support Facility #1, Williamstown, West 

Virginia, Per- and Polyfluoroalkyl Substances Impacted Sites ARNG Installations, 

Nationwide. March. 

Guelfo, J.L. and C.P. Higgins. 2013. Subsurface transport potential of perfluoroalkyl acids and 

aqueous film-forming foam (AFFF)-impacted sites. Environmental Science and 

Technology 47(9):4164-71. 

Higgins, C.P., and R.G. Luthy. 2006. Sorption of perfluorinated surfactants on sediments. 

Environmental Science and Technology 40 (23): 7251-7256. 

Interstate Technology Regulatory Council (ITRC). 2018. Environmental Fate and Transport for 

Per- and Polyfluoroalkyl Substances. March. 

U.S. Environmental Protection Agency (USEPA). 1980. Comprehensive Environmental

Response, Compensation, and Liability Act (CERCLA). 11 December. 
Site Inspection Report 

Williamstown AASF #1, West Virginia Version: FINAL 

EA Engineering, Science, and Technology, Inc., PBC 9-2

. 1994. National Oil and Hazardous Substances Pollution Contingency Plan (Final Rule).

40 Code of Federal Regulations Part 300; 59 Federal Register 47384. September. 

. 2001. Risk Assessment Guidance for Superfund, Volume I: Human Health Evaluation 

Manual (Part D, Standardized Planning, Reporting, and Review of Superfund Risk 

Assessments). December. 

. 2017. UCMR 3 (2013-2015) Occurrence Data by State. Occurrence Data for the 

Unregulated Contaminant Monitoring Rule. Accessed 9 July 2019 at 

https://www.epa.gov/dwucmr/occurrence-data-unregulated-contaminant-monitoring-rule. 

January. 

U.S. Fish and Wildlife Service. 2022. Endangered Species. http://ecos.fws.gov/ipac/. Accessed

28 October. 

Xiao, F., M. F. Simcik, T.R. Halbach, and J.S Gulliver. 2015, Perfluorooctane sulfonate (PFOS) 

and perfluorooctanoate (PFOA) in soils and groundwater of a U.S. metropolitan area: 

Migration and implications for human exposure. Water Research 72:64-74