FINAL

Site Inspection Report

Johnstown Army Aviation

Support Facility #2

Johnstown, Pennsylvania

Site Inspection for Perfluorooctanoic acid (PFOA),

Perfluorooctanesulfonic acid (PFOS), Perfluorohexanesulfonic

acid (PFHxS), Perfluorononanoic acid (PFNA),

Hexafluoropropylene oxide dimer acid (HFPO-DA), and 

Perfluorobutanesulfonic acid (PFBS) at ARNG Installations,

Nationwide 

August 2023 

Prepared for:

Army National Guard Bureau

111 S. George Mason Drive

Arlington, VA 22204

UNCLASSIFIED
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Table of Contents

Executive Summary ..............................................................................................................ES-1

1. Introduction ..................................................................................................................1-1

1.1 Project Authorization .............................................................................................1-1

1.2 SI 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........................................................................................................2-4

2.2.5 Current and Future Land Use......................................................................2-4

2.2.6 Sensitive Habitat and Threatened/ Endangered Species.............................2-4

2.3 History of PFAS Use..............................................................................................2-4

3. Summary of Areas of Interest .......................................................................................3-1

3.1 AOI 1 Hangar Apron Areas....................................................................................3-1

3.2 AOI 2 Drainage Areas ...........................................................................................3-1

3.3 AOI 3 Former Burn Area........................................................................................3-1

3.4 Adjacent Sources ..................................................................................................3-1

3.4.1 Drainage Ditch to Detention Pond ...............................................................3-1

3.4.2 Runway 15/33 .............................................................................................3-2

3.4.3 JCCA ARFF.................................................................................................3-2

3.4.4 Richland Township Fire Station ...................................................................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....................................................................................4-1

5. Site Inspection Activities ...............................................................................................5-1

5.1 Pre-Investigation Activities.....................................................................................5-1

5.1.1 Technical Project Planning ..........................................................................5-1

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

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

5.2 Soil Borings and Soil Sampling .............................................................................5-2

5.3 Permanent Well Installation and Groundwater Sampling.......................................5-4

5.4 Synoptic Water Level Measurements ....................................................................5-4

5.5 Surveying..............................................................................................................5-5

5.6 Investigation-Derived Waste..................................................................................5-5

5.7 Laboratory Analytical Methods ..............................................................................5-5

5.8 Deviations from SI QAPP Addendum ....................................................................5-5

6. Site Inspection Results .................................................................................................6-1

6.1 Screening Levels...................................................................................................6-1

6.2 Soil Physicochemical Analyses .............................................................................6-2
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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.........................................................6-3

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

7. Exposure Pathways......................................................................................................7-1

7.1 Soil Exposure Pathway .........................................................................................7-1

7.1.1 AOI 1...........................................................................................................7-1

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

7.1.3 AOI 3...........................................................................................................7-2

7.2 Groundwater Exposure Pathway...........................................................................7-2

7.2.1 AOI 1...........................................................................................................7-3

7.2.2 AOI 2...........................................................................................................7-3

7.2.3 AOI 3...........................................................................................................7-3

7.3 Surface Water and Sediment Exposure Pathway ..................................................7-3

7.3.1 AOI 1...........................................................................................................7-3

7.3.2 AOI 2...........................................................................................................7-4

7.3.3 AOI 3...........................................................................................................7-4

8. Summary and Outcome................................................................................................8-1

8.1 SI Activities............................................................................................................8-1

8.2 Outcome ...............................................................................................................8-1

9. References...................................................................................................................9-1
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Appendices

Appendix A Data Usability Assessment and Validation Reports

Appendix B Field Documentation

B1. Log of Daily Notice of Field Activities

B2. Sampling Forms

B3. Field Change Request Forms

B4. Survey Data

B5. Investigation-Derived Waste Polygons

Appendix C Photographic Log

Appendix D TPP Meeting Minutes

Appendix E Boring Logs and Well Construction Diagrams

Appendix F Analytical Results

Appendix G Laboratory Reports

Figures

Figure 2-1 Facility Location

Figure 2-2 Facility Topography

Figure 2-3 Groundwater Features

Figure 2-4 Groundwater and Bedrock Elevations, August 2022

Figure 2-5 Surface Water Features

Figure 3-1 Areas of Interest

Figure 5-1 Site Inspection Sample Locations

Figure 6-1 PFOA Detections in Soil

Figure 6-2 PFOS Detections in Soil

Figure 6-3 PFBS Detections in Soil

Figure 6-4 PFHxS Detections in Soil

Figure 6-5 PFNA Detections in Soil

Figure 6-6 PFOA, PFOS, and PFBS Detections in Groundwater

Figure 6-7 PFHxS and PFNA Detections in Groundwater

Figure 7-1 Conceptual Site Model, AOI 1

Figure 7-2 Conceptual Site Model, AOI 2

Figure 7-3 Conceptual Site Model, AOI 3

Tables

Table ES-1 Screening Levels (Soil and Groundwater)

Table ES-2 Summary of Site Inspection Findings and Recommendations

Table 5-1 Site Inspection Samples by Medium

Table 5-2 Boring Depths and Bedrock Elevations

Table 5-3 Permanent Monitoring Well Screen Intervals and Groundwater Elevations

Table 6-1 Screening Levels (Soil and Groundwater)

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

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

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

Table 6-5 PFOA, PFOS, PFBS, PFNA, and PFHxS Results in Groundwater

Table 8-1 Summary of Site Inspection Findings and Recommendations
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Acronyms and Abbreviations

% percent

°C degrees Celsius

°F degrees Fahrenheit

μg/kg micrograms per kilogram

AASF Army Aviation Support Facility

AECOM AECOM Technical Services, Inc.

AFFF aqueous film-forming foam

AMEC AMEC Earth & Environmental, Inc.

amsl above mean sea level

AOI Area of Interest

ARFF Aircraft Rescue and Fire Fighting

ARNG Army National Guard

bgs below ground surface 

CERCLA Comprehensive Environmental Response, Compensation, and Liability Act

CoC chain of custody

CSM conceptual site model

DA Department of the Army

DoD Department of Defense 

DQO data quality objective

DUA data usability assessment 

EDRTM Environmental Data Resources, Inc.TM

EIS extraction internal standards

ELAP Environmental Laboratory Accreditation Program

EM Engineer Manual

FAA Federal Aviation Administration

FedEx Federal Express

GIS Geographic Information System 

GPS Global positioning system 

GPRS Ground Penetrating Radar Systems

HDPE high-density polyethylene 

HFPO-DA hexafluoropropylene oxide dimer acid

IDW investigation-derived waste

ITRC Interstate Technology Regulatory Council

JCC Johnstown-Cambria County

JCCA Johnstown-Cambria County Airport

LC/MS/MS liquid chromatography with tandem mass spectrometry

MIL-SPEC military specification

MS/MSD matrix spike/ matrix spike duplicate

NAVD88 North American Vertical Datum 1988

NELAP National Environmental Laboratory Accreditation Program

ng/L nanograms per liter 

OSD Office of the Secretary of Defense 

PA Preliminary Assessment 
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PAANG Pennsylvania Air National Guard

PAARNG Pennsylvania Army National Guard

PADEP Pennsylvania Department of Environmental Protection

PaGWIS Pennsylvania Groundwater Information System

PFAS per- and polyfluoroalkyl substances

PFBS perfluorobutanesulfonic acid

PFHxS perfluorohexanesulfonic acid

PFNA perfluorononanoic acid

PFOA perfluorooctanoic acid

PFOS perfluorooctanesulfonic acid

PID photoionization detector

PQAPP Programmatic UFP-QAPP

PVC polyvinyl chloride

QA quality assurance

QAPP Quality Assurance Project Plan

QC quality control

QSM Quality Systems Manual

RI Remedial Investigation

SI Site Inspection

SL screening level

SOP standard operating procedure

TOC total organic carbon

TPP Technical Project Planning

UFP Uniform Federal Policy

US United States

USACE United States Army Corps of Engineers

USACHPPM United States Army Center for Health Promotion and Preventive Medicine

USAEC United States Army Environmental Command

USAR United States Army Reserves

USCS Unified Soil Classification System

USEPA United States Environmental Protection Agency

USFWS United States Fish and Wildlife Service

USMCR United States Marine Corps Reserve
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Executive Summary

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

Inspections (SIs) 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) dated 6 July 2022 (Assistant Secretary of Defense, 2022). The six

compounds listed in the OSD memorandum include perfluorooctanesulfonic acid (PFOS),

perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorohexanesulfonic acid

(PFHxS), hexafluoropropylene oxide dimer acid (HFPO-DA)1

, and perfluorobutanesulfonic acid

(PFBS). 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

used, stored, disposed, or released historically (see Table ES-2 for AOI locations). The objective

of the SI is to identify whether there has been a release to the environment from theAOIs 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 SLs for relevant

compounds. This SI was completed at the Johnstown Army Aviation Support Facility (AASF) #2

in Johnstown, Pennsylvania and determined further evaluation under the Comprehensive

Environmental Response, Compensation, and Liability Act (CERCLA) is warranted for AOI 1 and

AOI 2; no further evaluation is warranted for AOI 3 at this time. Johnstown AASF #2 will also be

referred to as the “facility” throughout this document. 

Johnstown AASF #2 is located in the northwestern portion of a parcel of land owned by the

Johnstown-Cambria County Airport Authority, within the Richland and Conemaugh Townships in

Cambria County, Pennsylvania. The facility is situated on property shared between United States

(US) Army Reserves, PennsylvaniaARNG (PAARNG), and US Marine Corps Reserve and is used

for administrative, training, mechanical/maintenance, and storage purposes. Johnstown AASF #2

serves as a PAARNG aviation maintenance and storage facility for rotary wing aircraft.

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

three AOIs were compared to OSD SLs. Table ES-2 summarizes the SI results for each AOI.

Based on the results of this SI, further evaluation under CERCLA is warranted in a Remedial

Investigation (RI) for AOI 1 and AOI 2; no further evaluation is warranted for AOI 3 at this time.

Given the level of uncertainty at AOI 3, additional sampling may be considered at this AOI during 

a future CERCLA phase. 

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) 

Analyteb

Residential

(Soil)

(μg/kg)a 

0-2 feet bgs

Industrial/ Commercial

Composite Worker

(Soil)

(μg/kg)a 

2-15 feet bgs

Tap Water

(Groundwater)

(ng/L)a

PFOA 19 250 6

PFOS 13 160 4 

PFBS 1,900 25,000 601 

PFHxS 130 1,600 39

PFNA 19 250 6

Notes:

bgs = below ground surface; μg/kg = micrograms per kilogram; ng/L = nanograms per liter

a.) Assistant Secretary of Defense, 2022. Risk Based Screening Levels in Groundwater and Soil using United States Environmental Protection

Agency’s (USEPA’s) Regional Screening Level Calculator. Hazard Quotient (HQ) = 0.1. 6 July 2022. 

b.) 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 HFPODA 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. 

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

AOI Potential 

Release Area

Soil – 

Source Area

Groundwater – 

Source Area Future Action

1 Hangar Apron

Areas Proceed to RI 

2 Drainage Areas Proceed to RI

3 Former Burn

Area

No further action

at this time

Legend:

 = detected; exceedance of the screening levels

 = detected; no exceedance of the screening levels

 = not detected
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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) 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) 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 perfluorooctanoic acid (PFOA), 

perfluorooctanesulfonic acid (PFOS), perfluorohexanesulfonic acid (PFHxS), perfluorononanoic

acid (PFNA), hexafluoropropylene oxide dimer acid (HFPO-DA)1

, and perfluorobutanesulfonic

acid (PFBS) at ARNG facilities nationwide. The ARNG performed this SI at the Johnstown Army

Aviation Support Facility (AASF) #2 in Johnstown, Pennsylvania. The Johnstown AASF #2 is also

referred to as the “facility” throughout this document. 

The SI project elements were performed in compliance with Comprehensive Environmental

Response, Compensation, and Liability Act (CERCLA; United States [US] 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 US Department of the Army (DA) requirements and guidance for field

investigations. 

1.2 SI Purpose

A PA was performed at Johnstown AASF #2 (AECOM Technical Services, Inc. [AECOM], 2020) 

that identified three Areas of Interest (AOIs) where PFAS-containing materials may have been

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 is required based on screening levels (SLs) for the relevant compounds. 

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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2. Facility Background

2.1 Facility Location and Description

Johnstown AASF #2 is located in the northwestern portion of a parcel of land owned by the

Johnstown-Cambria County Airport (JCCA) Authority, within the Richland and Conemaugh

Townships in Cambria County, Pennsylvania. The facility is approximately 5 miles east of the City

of Johnstown and 2 miles north of the intersection of Highway 219 and Highway 56. Figure 2-1

illustrates the location of Johnstown AASF #2; however, property boundaries are approximate,

based on Geographic Information System (GIS) database information provided by PAARNG, and

may not reflect all informal property agreements.

The JCCA is a joint civil and military airport, with the military comprising approximately 37 percent

(%) of all operations (US Army Center for Health Promotion and Preventive Medicine

[USACHPPM], 2006). Military occupants include PAARNG, Pennsylvania Air National Guard

(PAANG), the US Army Reserves (USAR), the US Marine Corps, and the US Marine Corps

Reserve (USMCR) (Army Public Health Center, 2018). In 1991, the US Government entered into

a long-term lease agreement with the JCCA Authority for the acquirement of approximately 70

acres at the JCC; the lease has since been amended by several supplemental lease agreements.

The USAR began construction of an Army Reserve Center Building on the facility property in

1997. The PAARNG AASF #2 was located in Washington, Pennsylvania at the time but then

relocated to the USAR ASF in 1997 (USACHPPM, 2006). Operational usage of the property was

shared between three military divisions: USAR, PAARNG, and USMCR. The PAANG is located

on separate property across the airport runway. In 2010, the PAARNG occupation was formalized

in a land lease agreement between the Secretary of the Army and the Commonwealth of

Pennsylvania that designated three buildings, a 3,247-square yard parking apron, and a 50,000-

square yard hangar apron for use by PAARNG. The land occupied by PAARNG is on a portion of

the land leased under the aforementioned lease with the Johnstown-Cambria County (JCC)

Authority. Both agreements are active and expire in 2051, although they may be extended every

10 years until 2081. The total acreage currently being leased and used by these three military

organizations is 106.502 acres.

2.2 Facility Environmental Setting

The JCCA is situated on a plateau that is a regional topographic high in the Allegheny Mountains;

therefore, surface water and presumably unconfined groundwater generally move radially from

this position. The surrounding topography is characterized by steep slopes and gently rolling hills

(Figure 2-2). Locally, elevations range from 1,880 feet above mean sea level (amsl) to 2,278 feet

amsl. The facility sits at an elevation of 2,253 feet amsl and generally slopes to the northwest.

The facility is northwest of the JCCA Runway 15/33. The area surrounding the JCCA is

predominantly undeveloped, wooded land, but the area has been zoned for office commercial,

light industrial, manufacturing, and single-family residential use (USACHPPM, 2006). Scattered

residential homes are located to the west and northwest. Agricultural lands are located beyond

the JCCA property to the east.

2.2.1 Geology

Johnstown AASF #2 is located within the Allegheny Mountain Section of the Appalachian Plateau

physiographic province, which is characterized by wide ridges separated by broad valleys and

increasing ridge elevations to the south (Commonwealth of Pennsylvania, 2018). The Ebensburg

anticline runs north to south and approximately bisects the JCCA (National Park Service, 2018).
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The surface soils at the facility are primarily disturbed and composed of fill material from airport

construction activities. Within the area, the majority of the original soils are from the CookportHazelton-Laidig Association. These soils are formed in residual and colluvial materials and have

moderately well- to well-drained, deep to moderately deep, and channery loam characteristics

(AMEC Earth & Environmental, Inc. [AMEC], 2003).

According to a 1994 geotechnical survey of the Johnstown AASF #2 property, the overburden

consists of a mixture of organic soil with sands, clay, and silty clay and has a thickness ranging

from 0.5 to 14 feet below ground surface (bgs); however, much of the overburden has since been

disturbed by construction activities (AMEC, 2003). The underlying bedrock belongs to the

Pennsylvanian-age Conemaugh Group, which is subdivided into the sedimentary bedrock units

of the Casselman and Glenshaw Formations. The facility sits squarely on the Glenshaw

Formation according to a geologic map of Cambria County (McElroy, 1993). The Saltsburg

member is the primary sandstone unit within the Glenshaw Formation and is prevalent in the hills

and ridges east of Johnstown. The Conemaugh Group is nearly 1,000 feet thick and consists

mainly of shales and sandstones and some beds of limestone. The Allegheny Formation underlies

the Conemaugh Group and includes the top of the Upper Freeport coal bed to the base of the

Brooksville coal bed. The thickness of the Allegheny Formation is between 220 and 290 feet

(Phalen and Martin, 1911). The youngest-age deposits are the Quaternary alluvium deposits

along the Conemaugh River and its tributaries (National Park Service, 2018) (Figure 2-3).

Starting with the eastern most boring locations (JTN-AOI01-03, JTN-AOI01-02, and JTN-AOI01-

01 – from east to west), bedrock was observed (based on pulverized rock due to the sonic drilling) 

between 1 and 2 feet bgs. No limestone was observed in any of these three borings, and 

weathered shale was documented in the western most location (JTN-AOI01-01) in the bottom 8

feet, corresponding to an elevation of 2,207 to 2,199 feet North American Vertical Datum 1988 

(NAVD88). Moving westward, bedrock was encountered in boring location JTN-AOI02-02 at 15 

feet bgs (elevation 2,203 feet NAVD88). Sandstone red beds (13 feet thick) were observed in this 

boring starting at 55 feet bgs (elevation 2,163 feet NAVD88), followed by 5 feet of gray to black 

claystone and shale and ending with 2 feet of red beds (sandstone) at an elevation of 2,143 feet 

NAVD88. The most westerly location (JTN-AOI03-02) encountered bedrock at the deepest 

elevation (elevation of 2,132 feet NAVD88 or 57 feet bgs) of all the borings conducted. The 

bedrock encountered was not sandstone but appeared to be calcitic and was interpreted to be 

more likely limestone lithology. 

Varying quantities of clay, silt, sand, and gravel were noted across all five borings. Specifically

noted material included lean clay, silt, sandy silt (with/without gravel), clayey sand (with/without

gravel), silty sand (with/without gravel), poorly graded sand, and weathered shale. These layers

ranged in thicknesses from a few inches to 38.5 feet. Boring logs are presented in Appendix E

and a bedrock surface map is presented in Figure 2-4.

2.2.2 Hydrogeology

The regional source for groundwater is the Pennsylvanian aquifer, which is part of theAppalachian

Plateau aquifer system. The Appalachian Plateau aquifer system consists of alternating 

sequences of sandstone, shale, clay, coal, and limestone (US Geological Survey, 1997). 

Groundwater yields average about 50 gallons per minute from the Pennsylvanian aquifer, in which 

the Conemaugh Group is considered a productive water bearing unit due to the presence of

sandstone (Skelly and Loy, Inc., 2010; AMEC, 2003). The coal beds and limestones that comprise 

the Appalachian Plateau aquifer system are also water bearing units but are not as productive as 

the sandstones (US Geological Survey, 1997). 

An Environmental Data Resources, Inc.TM (EDRTM) report conducted a well search for a 1-mile

radius surrounding the facility. Using additional online resources, such as state and local GIS
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databases, wells and water providers were researched to a 4-mile radius of the facility. Potable

water at the facility is supplied by the Southwestern Cambria County Water Authority and the

Greater Johnstown Water Authority. The Southwestern Cambria County Water Authority is a

distribution system that purchases water from Highland Sewer and Water Authority (Southwestern

Cambria County Water Authority, 2018). The Highland Sewer and Water Authority and the Greater

Johnstown Water Authority have surface water intakes at the North Fork, Dalton Run, Beaverdam

Run, Quemahoning, and Lloydell Reservoirs (AMEC, 2003; Highland Sewer and Water Authority,

2019). The closest reservoir to the facility (Dalton Run) is located approximately 8 miles to the

southwest.

Several domestic wells were identified, from the Pennsylvania Groundwater Information System

(PaGWIS) northeast and southeast of the facility, within 4 miles of the facility. Domestic wells are

typically screened within the Conemaugh Group and have static water levels ranging from 28 to

70 feet bgs. Several monitoring wells at the JCC are located approximately 0.5 miles to the east

and have static water level measurements ranging from 9 to 14 feet bgs, where bedrock was

encountered at 3 to 5 feet bgs and the monitoring wells were screened below the bedrock 

(Pennsylvania Department of Conservation & Natural Resources, n.d.). The groundwater flow

direction in the overburden likely follows the topographic gradient (generally trending west), but

groundwater flow direction in the bedrock is unknown (AMEC, 2003). During the SI, an existing 

well (designated JTN-AOI03-MW001) was discovered within AOI 3. No known well installation 

records were found for this well, but USAR personnel stated that this was a water supply well that 

was used for the concrete batch plant during airport tarmac construction. Groundwater features

are presented on Figure 2-3.

Depths to water measured in August 2022 during the SI ranged from 27.92 to 119.96 feet bgs.

Groundwater elevation contours from the SI are presented on Figure 2-4 and indicate the

groundwater flow direction at the facility is primarily to the southwest. Groundwater availability 

varied between wells installed during the SI due to differences in the lithology based on the vertical 

section drilled. A permanent well was installed at location JTN-AOI03-02, but the well was purged

dry and could not be sampled for groundwater. At JTN-AOI01-01, located at a higher elevation

than JTN-AOI03-02, groundwater production was higher because the porous sandstone, 

underlain by shale at this location, acts as a reservoir for water infiltrating from directly above. In

contrast, while JTN-AOI03-02 also consisted of sandstone in the upper section of the boring, the 

lithology is interpreted as transitioning to cemented limestone at approximately 50 to 55 feet bgs

(Appendix E). Because these units are nearly flat-lying, and based on relative elevations between

AOI 1 and AOI 3, the productive section present at JTN-AOI01-01 is considered missing (above)

JTN-AOI03-02. The well at JTN-AOI03-02 was installed within the interpreted limestone lithology 

where groundwater may have been initially present in possible fracture zones; however, it is likely 

due to the cementing observed, that groundwater recharge is limited.

2.2.3 Hydrology

Stormwater drainage from the hangar buildings (Buildings 292 and 288) and the apron areas are

captured by two stormwater detention ponds that lead into an intermittent, unnamed branch of

Solomon Run, which is a tributary of the Conemaugh River. The stormwater detention pond that

is located directly west of Building 292 is referred to as the “AFFF Pond”. According to the GIS

database information provided by PAARNG, the AFFF Pond and a portion of a drainage ditch that

leads into the second stormwater detention pond are located on facility property. The second

stormwater detention pond is located outside the facility property, to the north. Another intermittent

branch of Solomon Run is located southeast of the facility. Both branches flow southwest into

Solomon Run and then connect with the Conemaugh River, located approximately 3.5 miles west

of the facility. The general surface water flow direction from the facility is to the west and northwest

(Skelly and Loy, Inc., 2010). Surface water features are presented on Figure 2-5.
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 2-4

2.2.4 Climate 

Johnstown is in a humid subtropical climate zone that is generally characterized by cold and

temperate weather. The average high temperature for the summer is 78 degrees Fahrenheit (°F),

and the average winter low temperature is 20°F. The mean annual temperature is 47°F. The area

receives an average of 41 inches of precipitation throughout the year. Generally, the heaviest

rains occur from May to July, although the region experiences year-round rainfall (National

Weather Service, 2019).

2.2.5 Current and Future Land Use 

Johnstown AASF #2 serves as a PAARNG aviation maintenance and storage facility for rotary

wing aircraft. The facility is situated on property shared between USAR, PAARNG, and USMCR

and is used for administrative, training, mechanical/maintenance, and storage purposes. Related

infrastructure includes 12 buildings, tarmacs, hangar aprons, parking lots, storage lockers, two

large retention ponds, and one smaller detention pond designed to capture AFFF (Skelly and Loy,

Inc., 2010). Future property agreements between USAR and PAARNG over the occupation of

shared buildings and resources are currently planned. Otherwise, reasonably anticipated future

land use is not expected to change from the current land use described above. 

2.2.6 Sensitive Habitat and Threatened/ Endangered Species

A wildlife survey has not occurred at the facility, and the facility does not have any significant areas

of habitat. The following species have not been identified at the facility but may be present in the

surrounding area. 

The following birds, plants, insects, and mammals are federally endangered, threatened,

proposed, and/ or are listed as candidate species in Cambria County, Pennsylvania (US Fish and

Wildlife Service [USFWS], 2022). 

• Birds: Bald eagle, Haliaeetus leucocephalus (recovery)

• Flowering Plants: Northeastern bulrush, Scirpus ancistrochaetus (endangered)

• Insects: Monarch butterfly, Danaus plexippus (candidate)

• Mammals: Tricolored bat, Perimyotis subflavus (proposed endangered); Little brown bat,

Myotis lucifugus (under review); Indiana bat, Myotis sodalis (endangered); Northern LongEared Bat, Myotis septentrionalis (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 the Johnstown AASF #2 (AECOM, 2020). AFFF may have historically been

released at the facility during fire training exercises, fire suppression system releases, and other

release mechanisms. 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. 
0 0.5 1 2

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12420 Milestone Center Drive

Germantown, MD 20876

Facility Location

Base Map: Sources: Esri, HERE, Garmin, USGS,

Intermap, INCREMENT P, NRCan, Esri Japan, METI,

Legend

Estimated Facility

Boundary

Facility Boundary

John Cambria-County

Airport (Approximate)

Johnstown AASF #2

^_

AECOM 2-5
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12420 Milestone Center Drive

Germantown, MD 20876

Facility Topography

Base Map: USGS The National Map: National

Boundaries Dataset, 3DEP Elevation Program,

Legend

Estimated Facility

Boundary

Facility Boundary

John Cambria-County

Airport (Approximate)

AECOM 2-6
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Figure 2-3

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Japan, METI, Esri China (Hong Kong), Esri Korea, Esri (Thailand), NGCC, (c)

1:95,040 ­ 12420 Milestone Center Drive

Germantown, MD 20876

Legend

Estimated Facility Boundary

Facility Boundary

Water Body

River/Stream

Groundwater Flow Direction

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Glenshaw Formation

Casselman Formation

Allegheny Formation

Pottsville Formation

Mauch Chunk Formation

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Oswayo Formation, undivided

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1:2,400

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Bedrock Elevation Contour

Groundwater and Bedrock Elevations, August 2022

12420 Milestone Center Drive

Germantown, MD 20876

0 100 200 400

Feet

Notes:

* Excluded from contouring.

Groundwater and bedrock elevations in ft NAVD88

indicated for each boring/well as [Groundwater/Bedrock]

Due to sonic drilling, top of bedrock is determined by

evidence of pulverized rock.

AECOM 2-8
Solomon Run

Clapboard Run

Sandy Run

Peggys Run

Falls Run

Lower Stonycreek

River Watershed

South Fork Little

Conemaugh River

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Legend

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Facility Boundary

Water Body

River/Stream

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Figure 2-5

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1:31,680 ­ 12420 Milestone Center Drive

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Base Map: Sources: Esri, HERE, Garmin, USGS, Intermap, INCREMENT P, NRCan, Esri

Japan, METI, Esri China (Hong Kong), Esri Korea, Esri (Thailand), NGCC, (c)

AECOM 2-9
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 2-10

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Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 3-1

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, eight potential release areas were

identified at Johnstown AASF #2 and grouped into three AOIs (AECOM, 2020). The potential

release areas, and AOIs, are shown on Figure 3-1. 

3.1 AOI 1 Hangar Apron Areas

AOI 1 includes Building 292, Building 288, Tri-MaxTM Service Area, hangar apron, and Pump

House #1. Buildings 292 and 288 are aircraft hangars equipped with AFFF fire suppression

systems that have a history of releases due to trips, leaks, and testing. Tri-MaxTM fire extinguishers

were refilled with AFFF at the Tri-MaxTM Service Area, and four 55-gallon AFFF drums were

observed in storage at Pump House #1. The hangar apron was the site of familiarization training

and nozzle testing activities that utilized AFFF. Excess AFFF from fire crash trucks and Tri-MaxTM

fire extinguishers were also purged into the hangar apron drains prior to the disposal of the

equipment in 2017 or 2018.

3.2 AOI 2 Drainage Areas

AOI 2 includes the AFFF Pond and a portion of the drainage ditch that leads into a second offfacility stormwater detention pond. Both drainage areas lead to Solomon Run, which is a tributary

of the Conemaugh River. AFFF releases from AOI 1 are captured in surface water and sediment

in AOI 2. Throughout the years of facility operation, the water runoff in both drainage areas

occasionally has been observed to be foamy as a result of suspected AFFF releases in AOI 1. 

3.3 AOI 3 Former Burn Area

AOI 3 includes the Former Burn Area where AFFF releases may have occurred from fire training

activities. PAARNG personnel reported that only Tri-MaxTM fire extinguishers containing water

were used to extinguish the fires. The burn area was also used by USMCR and USAR, but their

activities at the site are unknown. The Former Burn Area was regraded and paved over around

2010, and the current area is a fenced motor pool. At the time of the fire training activities

(approximately 2004 to 2010), AOI 3 was located on unpaved surfaces. 

3.4 Adjacent Sources

Four off-facility, potential source areas were identified adjacent to the Johnstown AASF #2 during

the PA and are not associated with ARNG activities, except for the drainage ditch to detention 

pond adjacent source (Section 3.4.1). The adjacent potential source areas are shown on Figure

3-1 and described in the following sections for informational purposes only and were not

investigated as part of this SI.

3.4.1 Drainage Ditch to Detention Pond

The drainage ditch to detention pond source is the off-facility, downgradient portion of the drainage

ditch described in Section 3.2. The drainage ditch is a 0.5-mile riprap channel that leads into a 

second stormwater detention pond and then connects with an intermittent, unnamed stream of

Solomon Run. The second stormwater detention pond also receives drainage from paved lots

and buildings designated for USMCR or USAR usage (AECOM, 2020). The drainage ditch to

detention pond is downgradient from the facility, and PFAS contamination from this potential

source is not anticipated to migrate towards the facility.
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 3-2

3.4.2 Runway 15/33

Runway 15/33 trends northwest to southeast and is one of the two primary runways at JCCA.

Three aircraft accidents at Runway 15/33 occurred between 2006 and 2012, and an unspecified

amount of AFFF was used in the emergency response for each incident. Emergency responses

were conducted jointly by PAARNG, JCCA Aircraft Rescue and Fire Fighting (ARFF), and

Richland Township Fire Department per a mutual aid agreement between entities. Runway 15/33

is upgradient of the facility, and it is possible that the potential PFAS contamination from the

emergency responses are migrating towards the facility.

3.4.3 JCCA ARFF

The JCCAARFF maintains a maintenance facility on the northeast portion of JCCA along Airport

Road. There are two 60-gallon foam tank capacity ARFF firetrucks, 200-gallon barrels, and 5-

gallon buckets of 6% AFFF stored within the maintenance facility. Additionally, in accordance with

Federal Aviation Administration (FAA) regulations, the JCCA ARFF performed biannual AFFF

testing outside the maintenance facility. It was estimated that less than 5 gallons of 6% AFFF

concentrate were released during each testing event. After the AFFF was discharged, the area

was hosed down with water, and the runoff was captured in an adjacent retention pond. The JCCA

ARFF had FAA testing records available that date back to 2005. The JCCA ARFF is upgradient

of the facility, and it is possible the that potential PFAS contamination from the testing events are

migrating towards the facility.

3.4.4 Richland Township Fire Station

The Richland Township Fire Department has a fire station due south of the JCCA border. The

Richland Township Fire Station was identified as a potential adjacent source due to the potential

storage of AFFF and involvement in emergency responses with AFFF at JCCA. The Richland

Township Fire Station is cross-gradient of the facility, and it is possible that potential PFAS

contamination from the fire station is migrating towards the facility.
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Pump House #1

Tri-Max Service Area

AOI 3

AOI 2

AOI 1

Sandy

Run

Clapboard Run

Solomon Run

­ Figure 3-1

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4/12/2023

1:12,000

Area of Interest

Potential Release Area

Estimated Facility Boundary

Facility Boundary

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River/Stream

Surface Water Flow Direction

Groundwater Flow Direction

!P Domestic Well

A! Monitoring Well

A! Other/Unknown Well

Areas of Interest

12420 Milestone Center Drive

Germantown, MD 20876

0 500 1,000 2,000

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AECOM 3-3
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AECOM 3-4

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Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 4-1

4. Project Data Quality Objectives

As identified during the Data Quality Objective (DQO) process and outlined in the SI Quality

Assurance Project Plan (QAPP) Addendum (AECOM, 2021), 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 no further action 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 will recommend an AOI for Remedial Investigation (RI) if 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 included:

• The PA for Johnstown AASF #2 (AECOM, 2020);

• Analytical data from groundwater and soil samples collected as part of this SI in accordance

with the site-specific Uniform Federal Policy (UFP)-QAPP Addendum (AECOM, 2021); and

• Field data collected during the SI, including groundwater elevation and water quality

parameters measured at the time of sampling.

4.3 Study Boundaries

The scope of the SI was bounded by the property limits of the facility (Figure 2-2). 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 summer season, which was the earliest available

time field resources were available to complete the study. Vertical boundaries were established by the 

depth to encountered groundwater and sonic drilling refusal. 

4.4 Analytical Approach

Samples were analyzed by Pace Analytical Gulf Coast, accredited under the Department of

Defense (DoD) Environmental Laboratory Accreditation Program (ELAP; Accreditation Number

74960) and the National Environmental Laboratory Accreditation Program (NELAP; Certificate

Number 01955). Data were compared to applicable SLs within this document and decision rules

as defined in the SI QAPP Addendum (AECOM, 2021). 

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
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Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 4-2

whether the collected data are of the right type, quality, and quantity to support the decisionmaking (DoD, 2019a; DoD, 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. Multiple field and quality control (QC) samples displayed extraction 

internal standards (EIS) area counts outside the QC limits of 50%-150%. The field sample results 

that displayed EIS area counts less than 10% were initially flagged “X” while positive results were 

changed to estimate with a positive bias. These samples were re-extracted and reanalyzed 

outside technical holding time and displayed EIS area counts within QC limits in the reanalysis. 

The reanalyzed results were qualified appropriately and recommended to be retained in place of 

the “X” flagged data in the data set. These data are of sufficient quality to meet the objectives and

requirements of the SI QAPP Addendum (AECOM, 2021).
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 5-1

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 implemented

in accordance with the following approved documents: 

• Final Site Inspection Programmatic Uniform Federal Policy-Quality Assurance Project Plan

(PQAPP) dated March 2018 (AECOM, 2018a);

• Final Programmatic Accident Prevention Plan dated July 2018 (AECOM, 2018b);

• Final Preliminary Assessment Report, Johnstown Army Aviation Support Facility #2,

Johnstown, Pennsylvania dated July 2020 (AECOM, 2020);

• Final Site Inspection Uniform Federal Policy-Quality Assurance Project Plan Addendum,

Johnstown Army Aviation Support Facility #2, Johnstown, Pennsylvania dated December

2021 (AECOM, 2021); and

• Final Site Safety and Health Plan, Johnstown Army Aviation Support Facility #2, Johnstown,

Pennsylvania dated July 2022 (AECOM, 2022).

The SI field activities were conducted from 21 July to 10 August 2022 and consisted of utility

clearance, borings, soil sample collection, permanent monitoring well installations and

development, groundwater sample collection, and land surveying. Field activities were conducted

in accordance with the SI QAPP Addendum (AECOM, 2021), except as noted in Section 5.8. 

The following samples were collected during the SI and analyzed for a subset of 18 compounds

by liquid chromatography with tandem mass spectrometry (LC/MS/MS) compliant with Quality

Systems Manual (QSM) 5.3 Table B-15 to fulfill the project DQOs:

• Thirty (30) soil samples from five (5) borings and sixteen (16) hand auger locations;

• Four (4) groundwater samples from three (3) permanent well locations and one (1) existing

well (JTN-AOI03-MW001);

• Fifteen (15) quality assurance (QA)/ QC 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 media. 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, Field Change Request Forms

are provided in Appendix B3, land survey data are provided in Appendix B4, and investigationderived waste (IDW) polygons are provided in Appendix B5. 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 for each of these activities are presented below.

5.1.1 Technical Project Planning

The US Army Corps of Engineers (USACE) TPP Process, Engineer Manual (EM) 200-1-2 

(USACE, 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 
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 5-2

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 14 September 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, PAARNG, USACE, USAR, US Army Environmental

Command (USAEC), and Pennsylvania Department of Environmental Protection (PADEP).

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 (AECOM, 2021).

A TPP Meeting 3 was held after the field event to discuss the results of the SI. Meeting minutes

for TPP 3 are 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

AECOM’s drilling subcontractor, Cascade Technical Services, LLC., placed a ticket with the

Pennsylvania 811 utility clearance provider to notify them of intrusive work on 19 July 2022.

Additionally, AECOM contracted Ground Penetrating Radar Systems (GPRS), a private utility

location service, to perform utility clearance. GPRS performed utility clearance of the proposed

boring locations on 21 July 2022 with input from the AECOM field team and USAR facility staff.

General locating services and ground-penetrating radar were used to complete the clearance. To

verify utility clearance in the shallow subsurface where utilities would typically be encountered, all 

proposed boring locations were precleared, using a hand auger. Three of the five borings 

encountered shallow bedrock refusal prior to reaching the target depth of 5 feet bgs. The 

remaining two borings were able to be cleared, via hand auger, to 5 feet bgs.

5.1.3 Source Water and Sampling Equipment Acceptability

The potable water source at Johnstown AASF #2 was sampled on 12 October 2021 to assess

usability for decontamination of drilling equipment. Results of the sample collected at the Building

292 spigot (JTN-DECON-01) confirmed this source to be acceptable for use in this investigation;

therefore, it was used throughout the field activities. Specifically, the samples were analyzed by

LC/MS/MS compliant with QSM 5.3 Table B-15. The results of the decontamination water sample

associated with the wash rack spigot source used during the SI are provided in Appendix F. A

discussion of the results is presented in the DUA (Appendix A).

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

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

was provided in the Standard Operating Procedures (SOPs) appendix to the SI QAPP Addendum

(AECOM, 2021). Prior to the start of field work each day, a Sampling Checklist was completed as

an additional layer of control. The checklist served as a daily reminder to each field team member

regarding the allowable materials within the sampling environment.

5.2 Borings and Soil Sampling

Borings were installed in grass areas to avoid disturbing concrete or asphalt surfaces. Soil

samples were collected via sonic drilling technology, in accordance with the SI QAPP Addendum

(AECOM, 2021). A sonic drill rig was used to collect continuous soil cores to the target depth. A

hand auger was used to collect soil from within the top five feet of the boring, in accordance with

AECOM utility clearance procedures. The boring locations are shown on Figure 5-1, and depths

are provided Table 5-2. Several boring locations were adjusted within a 100-feet offset for reasons
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 5-3

including drill rig access, utility avoidance and bias toward sampling within observed drainage

features. Additional details regarding these adjustments are described in Section 5.8.

In general, three discrete soil samples were collected from the vadose zone for chemical analysis

from each boring: one surface soil sample (0 to 2 feet bgs), one subsurface soil sample

approximately 1 foot above the groundwater table or 1 foot above the bedrock, whichever was

encountered first, and one subsurface soil sample at the mid-point between the surface and the

groundwater table. Only two soil samples could be collected from boring location AOI02-02 due

to the presence of bedrock and lack of available soil below 15 feet bgs.

The soil cores were continuously logged for lithological descriptions by an AECOM field geologist

using the Unified Soil Classification System (USCS). A photoionization detector (PID) was used

to screen the breathing zone during boring activities as part of personal safety requirements.

Observations and measurements were recorded on boring logs (Appendix E) and in a nontreated field logbook (i.e., composition notebook). Depth interval, recovery thickness, PID

concentrations, moisture, relative density, color (using a Munsell soil color chart), and texture

(using the USCS) were recorded. The boring logs are provided in Appendix E.

Starting with the eastern most boring locations (JTN-AOI01-03, JTN-AOI01-02, and JTN-AOI01-

01 – from east to west), bedrock was observed (based on pulverized rock due to the sonic drilling) 

between 1 and 2 feet bgs. No limestone was observed in any of these three borings, and 

weathered shale was documented in the western most location (JTN-AOI01-01) in the bottom 8

feet, corresponding to an elevation of 2,207 to 2,199 feet NAVD88. Moving westward, bedrock 

was encountered in boring location JTN-AOI02-02 at 15 feet bgs (elevation 2,203 feet NAVD88). 

Sandstone red beds (13 feet thick) were observed in this boring starting at 55 feet bgs (elevation 

2,163 feet NAVD88), followed by 5 feet of gray to black claystone and shale and ending with 2 

feet of red beds (sandstone) at an elevation of 2,143 feet NAVD88. The most westerly location 

(JTN-AOI03-02) encountered bedrock at the deepest elevation (elevation of 2,132 feet NAVD88

or 57 feet bgs) of all the borings conducted. The bedrock encountered was not sandstone but 

appeared to be calcitic and was interpreted to be more likely limestone lithology. 

Varying quantities of clay, silt, sand, and gravel were noted across all five borings. Specifically

noted material included lean clay, silt, sandy silt (with/without gravel), clayey sand (with/without

gravel), silty sand (with/without gravel), poorly graded sand, and weathered shale. These layers

ranged in thicknesses from a few inches to 38.5 feet. Boring logs are presented in Appendix E.

Each soil sample was collected into laboratory-supplied PFAS-free high-density polyethylene

(HDPE) bottles and labeled using a PFAS-free marker or pen. Samples were packaged on ice

and transported via Federal Express (FedEx) under standard chain of custody (CoC) procedures

to the laboratory and analyzed by LC/MS/MS compliant with QSM 5.3 Table B-15, total organic

carbon (TOC) (USEPA Method 9060A) and pH (USEPA Method 9045D) in accordance with the

SI QAPP Addendum (AECOM, 2021).

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

as the accompanying samples. Matrix spike/ matrix spike duplicates (MS/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, equipment rinsate blanks were collected at a rate of 5% 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.

Sonic borings were converted into permanent wells, except for location JTN-AOI01-02 that was

dry after boring installation. JTN-AOI01-02 was abandoned using bentonite chips at the

completion of sampling activities, in accordance with the SI QAPP Addendum (AECOM, 2021).
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 5-4

5.3 Permanent Well Installation and Groundwater Sampling

During the SI, four permanent monitoring wells were installed within or downgradient of potential

source areas. Of the four newly-installed permanent wells, one well could not be sampled due to

a lack of available groundwater. Additionally, an existing well (JTN-AOI03-MW001) was

discovered at AOI 3 during SI field activities. No known well installation records were found for 

this well, but USAR personnel stated that the concrete batch plant, in place during airport tarmac 

construction, used this well as a water supply well. The bottom of the well was tagged around 292 

feet bgs, and other measured well construction details are provided in Table 5-3. This well was

sampled for groundwater, as described further in Section 5.8. The locations of the wells are

shown on Figure 5-1.

A sonic drill rig was used to install four 2-inch diameter monitoring wells. The monitoring wells

were constructed with Schedule 40 polyvinyl chloride (PVC), flush threaded 10-foot sections of

riser, 0.010-inch slotted 10-foot well screens, and a threaded bottom cap. A filter pack of 20/40

silica sand was installed in the annulus around the well screen to a minimum of 2-feet above the

well screen. A 2-foot-thick bentonite seal was placed above the filter sand and hydrated with

distilled water. Bentonite grout was placed in the well annulus from the top of the bentonite seal

to ground surface. The bentonite grout was allowed to set for 24 hours prior to well completion in

accordance with the SI QAPP Addendum (AECOM, 2021). All monitoring wells were completed

with flush mount well vaults. The screen intervals of the groundwater monitoring wells are

provided in Table 5-3.

Development and sampling of wells were completed in accordance with the SI QAPP Addendum

(AECOM, 2021). The newly installed monitoring wells were developed no sooner than 24 hours

following installation by pumping and surging using a variable speed submersible pump. Samples

were collected no sooner than 24 hours following development via low-flow sampling methods

using a QED Sample Pro® bladder pump with disposable PFAS-free, HDPE tubing. Due to the

sampling depth limitations of the bladder pump, a Geotech Geosub submersible pump with a drop

tube assembly was used to sample the existing well, JTN-AOI03-MW001. New tubing was used

at each well and the pumps were decontaminated between each well. The wells were purged at

a rate determined in the field to reduce draw down prior to sampling. Water quality parameters

(e.g., temperature, specific conductance, pH, dissolved oxygen, and oxidation-reduction

potential) were measured using a water quality meter and recorded on the field sampling form

(Appendix B2). Water levels were measured to the nearest 0.01 inch and recorded. Additionally,

a subsample of each groundwater sample was collected in a separate container, and a shaker

test was completed to identify if there were any foaming. No foaming was noted in any of the

groundwater samples.

Each sample was collected into laboratory-supplied PFAS-free HDPE bottles and labeled using

a PFAS-free marker or pen. Samples were packaged on ice and transported via FedEx under

standard CoC procedures to the laboratory and analyzed by LC/MS/MS compliant with QSM 5.3

Table B-15 in accordance with the SI QAPP Addendum (AECOM, 2021).

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

as the accompanying samples. MS/MSDs were collected at a rate of 5% and analyzed for the

same parameters as the accompanying samples. A temperature blank was placed in each cooler

to ensure that samples were preserved at or below 6°C during shipment.

5.4 Synoptic Water Level Measurements

A synoptic groundwater gauging event was performed on 10 August 2022. Groundwater elevation

measurements were collected from four new permanent monitoring wells and one existing well, 

JTN-AOI03-MW001. Water level measurements were taken from the northern side of the well
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 5-5

casing. A groundwater flow contour map is provided in Figure 2-4. Groundwater elevation data

are provided in Table 5-3.

5.5 Surveying

The northern side of each well casing was surveyed by Pennsylvania-licensed land surveyors

following guidelines provided in the SOPs provided in the SI QAPP Addendum (AECOM, 2021).

Survey data from the newly installed wells and the existing well, on the facility were collected on

4 August 2022 in the applicable Universal Transverse Mercator zone projection with Pennsylvania

State Plane South Coordinate System Datum (horizontal) and North American Vertical Datum

1988 (vertical). The surveyed well data are provided in Appendix B4.

5.6 Investigation-Derived Waste

As of the date of this report, the disposal of IDW is not regulated federally. IDW generated during

the SI is considered non-hazardous waste and was managed in accordance with the SI QAPP

Addendum (AECOM, 2021) and with the DA Guidance for Addressing Releases of PFAS, Q18 (DA,

2018).

Solid IDW (i.e., soil cuttings) generated during the SI activities were either left in place at the point

of the source or distributed in a designated IDW discharge location downgradient of AOI 3, as

described further in Section 5.8. This IDW was not sampled and assumes the PFAS

characteristics of the associated soil samples collected from that source location.

Liquid IDW generated during SI activities (i.e. purge water, development water, and

decontamination fluids) was discharged directly to the ground surface slightly downgradient of the

source. This IDW was not sampled and assumes the PFAS characteristics of the associated

groundwater samples collected from that source location.

Geographic coordinates were collected using a global positioning system (GPS) around each

location where IDW was placed (i.e., an IDW polygon). The IDW polygons are displayed on the

figure in Appendix B5.

Other solids such as spent personal protective equipment, plastic sheeting, tubing, rope, unused

monitoring well construction materials, and other environmental media generated during the field

activities were disposed of at a licensed solid waste landfill.

5.7 Laboratory Analytical Methods

Samples were analyzed by LC/MS/MS compliant with QSM 5.3 Table B-15 at Pace Analytical Gulf

Coast in Baton Rouge, Louisiana, a DoD ELAP and NELAP certified laboratory. Soil samples

were also analyzed for TOC using USEPA Method 9060A and pH by USEPA Method 9045D.

5.8 Deviations from SI QAPP Addendum

Three deviations from the SI QAPP Addendum were identified during review of the field

documentation. The deviations are noted below and are documented in Field Change Request

Forms (Appendix B3):

• Prior to the SI field activities, one alternate boring location for JTN-AOI01-01 was proposed

for utility avoidance, and three alternate boring locations for AOI 3 were proposed to avoid

a potential construction area. Both the proposed and original locations were marked and

cleared for utilities during the utility clearance event on 21 July 2022. The final placement of

the borings was determined during subsequent field activities. These proposed boring 
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 5-6

locations were documented in a field change request form dated 28 March 2022 and

provided in Appendix B3. 

• During the SI field activities, the AOI 2 well construction was changed to flush mount

completion instead of stick-up completion with bollards. Since AOI 2 was in the mowing path

area, this change was made to help avoid potential obstructions for landscaping equipment.

Additionally, an alternate IDW discharge location was identified downgradient of AOI 3 for

soil IDW generated from AOI 1. The alternate IDW discharge location was proposed by

PAARNG and approved by the USAR facilities manager to assist with foreign object debris

management at AOI 1. These actions were documented in a field change request form

dated 26 July 2022 and provided in Appendix B3.

• During the SI field activities, shallow bedrock was encountered above 5 feet bgs at all

attempted boring locations, except for one location (JTN-AOI03-02). Additionally, the sonic

rig was seizing and experiencing mechanical failures due to the pressure exerted when

encountering the various bedrock lithologies. The permanent wells that were able to be

successfully installed had generally low groundwater recharge rates. Therefore, in

concurrence with the project delivery team, the following deviations were implemented and

documented in a field change request form dated 3 August 2022 (Appendix B3):

• Seven surface soil samples were added to the sampling plan and collected at the

facility drainage features (see Figure 5-1). The additional surface soil samples were

identified as JTN-AOI01-04, JTN-AOI01-05, JTN-AOI01-06, JTN-AOI02-09, JTNAOI03-04, JTN-AOI03-05, and JTN-AOI03-06.

• The drilling for the permanent well at JTN-AOI02-02 was limited to 75 feet bgs.

• The proposed permanent wells for JTN-AOI02-01, JTN-AOI02-03, JTN-AOI03-01,

and JTN-AOI03-03 were converted to surface soil sample locations.

• An existing well (designated JTN-AOI03-MW001) was discovered within AOI 3 and,

with USAR’s approval, the groundwater was sampled.
Table 5-1

Site Inspection Samples by Medium

Site Inspection Report, Johnstown AASF #2, Pennsylvania

Sample Identification

Sample

Collection 

Date/Time

Sample 

Depth 

(feet bgs)

LC/MS/MS compliant with QSM 5.3 Table B-15TOC(USEPA Method 9060A)pH (USEPA Method 9045D)

Comments

JTN-AOI01-01-SB-00-02 7/28/2022 7:45 0 - 2 x

JTN-AOI01-01-SB-00-02-D 7/28/2022 7:45 0 - 2 x Field Duplicate

JTN-AOI01-01-SB-00-02-MS 7/28/2022 7:45 0 - 2 x MS

JTN-AOI01-01-SB-00-02-MSD 7/28/2022 7:45 0 - 2 x MSD

JTN-AOI01-01-SB-23-25 7/28/2022 15:45 23 - 25 x

JTN-AOI01-01-SB-30-32 7/29/2022 8:00 30 - 32 x

JTN-AOI01-02-SB-00-01 7/26/2022 11:15 0 - 1 x x x

JTN-AOI01-02-SB-12-14 7/26/2022 14:30 12 - 14 x

JTN-AOI01-02-SB-25-27 7/26/2022 9:00 25 - 27 x

JTN-AOI01-03-SB-00-01 7/25/2022 14:15 0 - 1 x

JTN-AOI01-03-SB-10-12 7/25/2022 18:15 10 - 12 x

JTN-AOI01-03-SB-15-17 7/25/2022 18:00 15 - 17 x

JTN-AOI01-04-HA-00-02 8/2/2022 16:30 0 - 2 x

JTN-AOI01-05-HA-00-01 8/2/2022 17:00 0 - 2 x

JTN-AOI01-06-HA-00-02 8/2/2022 16:00 0 - 2 x

JTN-AOI02-01-HA-00-02 8/5/2022 10:10 0 - 2 x

JTN-AOI02-02-SB-00-02 8/3/2022 14:15 0 - 2 x

JTN-AOI02-02-SB-13-15 8/3/2022 17:00 13 - 15 x x x

JTN-AOI02-02-SB-13-15-D 8/3/2022 17:00 13 - 15 x Field Duplicate

JTN-AOI02-02-SB-13-15-MS 8/3/2022 17:00 13 - 15 x x MS for TOC/pH

JTN-AOI02-02-SB-13-15-MSD 8/3/2022 17:00 13 - 15 x x MSD for TOC/pH

JTN-AOI02-03-HA-00-02 8/5/2022 8:35 0 - 2 x

JTN-AOI02-04-HA-00-02 7/28/2022 13:40 0 - 2 x

JTN-AOI02-04-HA-00-02-D 7/28/2022 13:40 0 - 2 x Field Duplicate

JTN-AOI02-05-HA-00-02 8/5/2022 8:50 0 - 2 x

JTN-AOI02-06-HA-00-02 8/5/2022 9:05 0 - 2 x

JTN-AOI02-07-HA-00-02 8/5/2022 9:20 0 - 2 x

JTN-AOI02-08-HA-00-02 8/5/2022 9:50 0 - 2 x

JTN-AOI02-09-HA-00-01 8/5/2022 10:30 0 - 1 x

JTN-AOI03-01-HA-00-02 7/28/2022 14:00 0 - 2 x

JTN-AOI03-02-SB-00-02 7/28/2022 12:00 0 - 2 x

JTN-AOI03-02-SB-13-15 8/1/2022 10:45 13 - 15 x

JTN-AOI03-02-SB-46-48 8/1/2022 17:00 46 - 48 x

JTN-AOI03-02-SB-46-48-D 8/1/2022 17:00 46 - 48 x x x Field Duplicate

JTN-AOI03-03-HA-00-02 8/4/2022 14:15 0 - 2 x

JTN-AOI03-04-HA-00-02 8/4/2022 12:30 0 - 2 x

JTN-AOI03-05-HA-00-02 8/4/2022 13:30 0 - 2 x

JTN-AOI03-06-HA-00-02 8/4/2022 13:00 0 - 2 x

JTN-AOI01-01-GW 8/5/2022 15:30 NA x

JTN-AOI01-01-GW-D 8/5/2022 15:30 NA x Field Duplicate

JTN-AOI01-03-GW 8/5/2022 13:00 NA x

JTN-AOI01-03-GW-MS 8/5/2022 13:00 NA x MS

JTN-AOI01-03-GW-MSD 8/5/2022 13:00 NA x MSD

JTN-AOI02-02-GW 8/10/2022 12:30 NA x

JTN-AOI03-MW001-GW 8/9/2022 18:00 NA x

Groundwater Samples

Soil Samples

Equipment Blank Samples

AECOM 5-7
Table 5-1

Site Inspection Samples by Medium

Site Inspection Report, Johnstown AASF #2, Pennsylvania

Sample Identification

Sample

Collection 

Date/Time

Sample 

Depth 

(feet bgs)

LC/MS/MS compliant with QSM 5.3 Table B-15TOC(USEPA Method 9060A)pH (USEPA Method 9045D)

Comments

JTN-DECON-01 10/12/2021 14:45 NA x

Decontamination Water 

Sample

JTN-DECON-02 7/25/2022 19:00 NA x

Decontamination Water 

Sample

JTN-ERB-01 7/26/2022 10:45 NA x

Equipment Blank from Hand 

Auger

JTN-ERB-02 8/2/2022 14:45 NA x

Equipment Blank from Drill

Shoe

JTN-ERB-03 8/10/2022 13:00 NA x

Equipment Blank from 

Bladder Pump

JTN-ERB-04 8/10/2022 13:30 NA x

Equipment Blank from 

Development Pump

Notes:

AASF = Army Aviation Support Facility

bgs = below ground surface

ERB = equipment rinsate blank

FD = field duplicate

LC/MS/MS = Liquid Chromatography Mass Spectrometry

MS/MSD = matrix spike/ matrix spike duplicate

QSM = Quality Systems Manual

TOC = total organic carbon

USEPA = United States Environmental Protection Agency

AECOM 5-8
Table 5-2

Borings Depths and Bedrock Elevations

Site Inspection Report, Johnstown AASF #2, Pennsylvania

Area of Interest Boring ID Boring Depth 

(feet bgs)

Ground 

Surface 

Elevation 

(feet NAVD88)

Depth to Top of 

Bedrock1 

(feet bgs)

Top of Bedrock 

Elevation

(feet NAVD88)

JTN-AOI01-01 50 2249.13 2 2247.13

JTN-AOI01-02 60 2257.86 1 2256.86

JTN-AOI01-03 36 2260.35 1 2259.35

2 JTN-AOI02-02 75 2217.90 15 2202.90

3 JTN-AOI03-02 75 2188.62 57 2131.62

Notes:

1 Due to sonic drilling, top of bedrock is determined by evidence of pulverized rock. 

AASF = Army Aviation Support Facility

bgs = below ground surface

NAVD88 = North American Vertical Datum 1988

1

AECOM 5-9
Table 5-3

Permanent Monitoring Well Screen Intervals and Groundwater Elevations

Site Inspection Report, Johnstown AASF #2, Pennsylvania

Area of 

Interest Monitoring Well ID Screen Interval (feet bgs)

Top of Casing 

Elevation 

(feet NAVD88)

Ground Surface 

Elevation 

(feet NAVD88)

Depth to Water2

(feet btoc)

Depth to Water2

(feet bgs)

Groundwater 

Elevation 

(feet NAVD88)

JTN-AOI01-01 38 - 48 2248.83 2249.13 32.15 32.45 2216.68

JTN-AOI01-03 26 - 36 2260.04 2260.35 27.61 27.92 2232.43

2 JTN-AOI02-02 65 - 75 2217.59 2217.90 43.80 44.11 2173.79

JTN-AOI03-MW001 Unknown1 2205.68 2204.24 121.40 119.96 2084.28

JTN-AOI03-02 60 - 70 2188.36 2188.62 70.10 70.35 2118.26

Notes:

1 Screen interval of existing water supply well JTN-AOI03-MW001 is unknown.

2 Synoptic gauging event occurred on 10 August 2022.

AASF = Army Aviation Support Facility

bgs = below ground surface

btoc = below top of casing

NAVD88 = North American Vertical Datum 1988

1

3

AECOM 5-10
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 5-11

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Tri-Max Service Area

Former Burn Area

AFFF Pond

Building 292

Drainage Ditch

Building 288

Pump House #1

JTN-AOI01-01

JTN-AOI01-02

JTN-AOI01-03

JTN-AOI02-01

JTN-AOI02-02

JTN-AOI02-03 JTN-AOI02-04

JTN-AOI02-05

JTN-AOI02-06

JTN-AOI02-07

JTN-AOI02-08

JTN-AOI03-01

JTN-AOI03-02

JTN-AOI03-03

JTN-AOI01-04

JTN-AOI01-05

JTN-AOI01-06

JTN-AOI02-09

JTN-AOI03-04

JTN-AOI03-05

JTN-AOI03-06

JTN-AOI03-MW001

Bldg 230

Bldg 200

Bldg 195

Readiness

Center

Storage Bldg

AOI 3

AOI 2

AOI 1

­ Figure 5-1

CLIENT

REVISED

SCALE

PROJECT

ARNG

Site Inspection at Johnstown AASF #2, PA

3/15/2023

3/15/2023

3/15/2023

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Area of Interest

Potential Release Area

Estimated Facility Boundary

Facility Boundary

Roadway/Parking

Groundwater Flow Direction

Site Inspection Sample Locations

12420 Milestone Center Drive

Germantown, MD 20876

0 100 200 400

Feet

AECOM 5-12
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 6-1

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. A discussion of the results for each AOI is provided in Section 6.3

through Section 6.5. Table 6-2 through Table 6-5 present results in soil or groundwater 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, theAOI 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 below.

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

Analyteb

Residential

(Soil)

(μg/kg)a 

0-2 feet bgs

Industrial/

Commercial

Composite

Worker

(Soil)

(μg/kg)a 

2-15 feet bgs

Tap Water

(Groundwater)

(ng/L)a

PFOA 19 250 6 

PFOS 13 160 4

PFBS 1,900 25,000 601 

PFHxS 130 1,600 39

PFNA 19 250 6 

Notes:

bgs = below ground surface; μg/kg = micrograms per kilogram; ng/L = nanograms per liter

a.) Assistant Secretary of Defense, 2022. Risk Based Screening Levels in Groundwater and Soil using United States Environmental Protection

Agency’s (USEPA’s) Regional Screening Level Calculator. Hazard Quotient (HQ) = 0.1. 6 July 2022. 

b.) 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 HFPODA 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. 

The data in the subsequent sections are compared to 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 feet bgs) 

and the industrial/commercial worker scenario is applied to shallow subsurface soil results (2 to

15 feet bgs). The SLs are not applied to deep subsurface soil results (>15 feet bgs) because 15

feet is the anticipated limit of construction activities. 
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 6-2

6.2 Soil Physicochemical Analyses

To provide basic soil parameter information, soil samples were analyzed for TOC and pH, which

are important for evaluating transport through the soil medium. Appendix F contains the results

of the 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 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 (for example, pH and presence

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

6.3 AOI 1 

This section presents the analytical results for soil and groundwater in comparison to SLs for AOI

1: Hangar Apron Areas. The soil and groundwater results are summarized on Table 6-2 through

Table 6-5. Soil and groundwater results are presented on Figure 6-1 through Figure 6-7. 

6.3.1 AOI 1 Soil Analytical Results 

Figure 6-1 through Figure 6-5 present the ranges of detections of the relevant compounds in soil. 

Table 6-2 through Table 6-4 summarize the soil results. 

Soil was sampled from surface soil (between 0 and 2 feet bgs) from JTN-AOI01-01 through JTNAOI01-06. Soil was also sampled from shallow subsurface soil (between 10 and 14 feet bgs) from

JTN-AOI01-02 and JTN-AOI01-03 and deep subsurface soil (between 15 and 32 feet bgs) from

borings JTN-AOI01-01 through JTN-AOI01-03. 

All detected concentrations of the relevant compounds were below the residential SLs in surface

soil. The following ranges of concentrations were measured:

• PFOA was detected ranging from 0.119 J micrograms per kilogram (μg/kg) in JTNAOI01-01 to 2.92 μg/kg in JTN-AOI01-05.

• PFOS was detected ranging from 0.063 J μg/kg in JTN-AOI01-03 to 7.56 μg/kg in JTNAOI01-05.

• PFHxS was detected ranging from 0.083 J μg/kg in JTN-AOI01-01 to 0.887 J μg/kg in

JTN-AOI01-05.

• PFNA was detected ranging from 0.133 J μg/kg in JTN-AOI01-01 to 2.71 μg/kg in JTNAOI01-05.

• PFBS was detected ranging from 0.036 J μg/kg in JTN-AOI01-02 to 0.040 J+ μg/kg in

JTN-AOI01-06.

PFOS was the most frequently detected compound (measured in all seven surface soil samples) 

and highest detected compound at 7.56 μg/kg in surface soil. No relevant compounds were

detected in the shallow subsurface soil samples. Only PFOS was detected, at 0.068 J+ μg/kg and

0.105 J μg/kg, in the deep subsurface soil samples from JTN-AOI01-01 and JTN-AOI01-02, 

respectively. 
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 6-3

6.3.2 AOI 1 Groundwater Analytical Results

Figure 6-6 and Figure 6-7 present the ranges of detections of the relevant compounds in

groundwater. Table 6-5 summarizes the groundwater results.

Groundwater was sampled from permanent monitoring wells JTN-AOI01-01 and JTN-AOI01-03.

PFOA and PFOS exceeded their SLs in groundwater at JTN-AOI01-01. PFOA exceeded the SL

of 6 nanograms per liter (ng/L) with a maximum concentration of 9.46 ng/L. PFOS exceeded the

SL of 4 ng/L with a maximum concentration of 68.4 ng/L. PFHxS, PFNA, and PFBS were detected

in groundwater, at concentrations below their SLs. The maximum concentrations and SLs of 

PFHxS, PFNA, and PFBS were 22.9 ng/L (SL of 39 ng/L), 3.06 J ng/L (SL of 6 ng/L), and 2.63 J 

ng/L (SL of 601 ng/L), respectively. 

6.3.3 AOI 1 Conclusions

Based on the results of the SI, PFOA, PFOS, PFHxS, PFNA, and PFBS were detected in surface 

soil below their residential SLs. No relevant compounds were detected in shallow subsurface soil. 

PFOA and PFOS were detected in groundwater, at concentrations above their SLs. Based on the

exceedances of the SLs in groundwater, further evaluation at AOI 1 is warranted.

6.4 AOI 2

This section presents the analytical results for soil and groundwater in comparison to SLs for AOI

2: Drainage Areas. The results in soil and groundwater are summarized on Table 6-2, Table 6-3,

and Table 6-5. Soil and groundwater results are presented on Figure 6-1 through Figure 6-7.

6.4.1 AOI 2 Soil Analytical Results

Figure 6-1 through Figure 6-5 present the ranges of detections of the relevant compounds in soil.

Table 6-2 and Table 6-3 summarize the soil analytical results.

Soil was sampled from surface soil (between 0 and 2 feet bgs) from JTN-AOI02-01 through JTNAOI02-09. Shallow subsurface soil samples (between 13 and 15 feet bgs) were also collected

from JTN-AOI02-02.

PFOA, PFOS, and PFNA were detected in surface soil, at concentrations above their residential

SLs. PFOA exceeded the residential SL of 19 μg/kg, with a concentration of 36.2 μg/kg in JTNAOI02-06. PFOS exceeded the residential SL of 13 μg/kg, with concentrations of 439 μg/kg and

19.4 μg/kg in JTN-AOI02-06 and JTN-AOI02-07, respectively. PFNA exceeded the residential SL

of 19 μg/kg, with a concentration of 34.9 μg/kg in JTN-AOI02-06. PFHxS and PFBS were detected

at concentrations below their SLs, with reported concentrations less than 0.622 J μg/kg. No

relevant compounds were detected in subsurface soil.

6.4.2 AOI 2 Groundwater Analytical Results

Figure 6-6 and Figure 6-7 present the ranges of detections of the relevant compounds in

groundwater. Table 6-5 summarizes the groundwater analytical results.

Groundwater was sampled from permanent monitoring well JTN-AOI02-02. No relevant

compounds were detected in the groundwater sample collected from this well.
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 6-4

6.4.3 AOI 2 Conclusions

Based on the results of the SI, PFOA, PFOS, and PFNA were detected in soil above their SLs.

No relevant compounds were detected in groundwater. Based on the exceedances of the SLs in

soil, further evaluation at AOI 2 is warranted.

6.5 AOI 3 

This section presents the analytical results for soil and groundwater in comparison to SLs for AOI

3: Former Burn Area. The results in soil and groundwater are presented in Table 6-2 through

Table 6-5. Soil and groundwater results are presented on Figure 6-1 through Figure 6-7. 

6.5.1 AOI 3 Soil Analytical Results 

Figure 6-1 through Figure 6-5 present the ranges of detections of the relevant compounds in soil.

Table 6-2 through Table 6-4 summarize the soil results. 

Soil was sampled from surface soil (between 0 and 2 feet bgs) from JTN-AOI03-01 through JTNAOI03-06. Soil was also sampled from shallow subsurface soil (between 13 and 15 feet bgs) and

deep subsurface soil (between 46 and 48 feet bgs) from JTN-AOI03-02. 

All detected concentrations of the relevant compounds were below their residential SLs in surface 

soil. The following ranges of concentrations were measured:

• PFOA was detected ranging from 0.224 J+ μg/kg in JTN-AOI03-05 to 0.621 J μg/kg in

JTN-AOI03-02.

• PFOS was detected ranging from 0.218 J+ μg/kg in JTN-AOI03-06 to 11.5 μg/kg in JTNAOI03-02.

• PFHxS was detected ranging from 0.033 J μg/kg in JTN-AOI03-01 to 0.590 J μg/kg in

JTN-AOI03-02.

• PFNA was detected ranging from 0.044 J μg/kg in JTN-AOI03-01 to 0.499 J μg/kg in

JTN-AOI03-02.

• PFBS was detected ranging from 0.039 J+ μg/kg in JTN-AOI03-03 to 0.086 J+ μg/kg in

JTN-AOI03-05.

PFOS was the most frequently detected compound (measured in all six surface soil samples) and

highest detected compound at 11.5 μg/kg in surface soil. PFOS and PFNA were also detected

below their industrial/commercial worker SLs in shallow subsurface soil, at concentrations of

0.309 J and 0.026 J μg/kg, respectively. No relevant compounds were detected in the deep

subsurface soil samples. 

6.5.2 AOI 3 Groundwater Analytical Results 

Figure 6-6 and Figure 6-7 present the ranges of detections of the relevant compounds in

groundwater. Table 6-5 summarizes the groundwater results. 

Groundwater was sampled from the existing well JTN-AOI03-MW001. PFOS was detected in

groundwater at a concentration of 1.51 J ng/L below the SL of 4 ng/L. No other relevant

compounds were detected. 
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 6-5

6.5.3 AOI 3 Conclusions

Based on the results of the SI, PFOA, PFOS, PFHxS, PFNA, and PFBS were detected in soil,

below their SLs, and PFOS was detected in groundwater at a concentration below its SL;

therefore, no further evaluation at AOI 3 is warranted.
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 6-6

THIS PAGE INTENTIONALLY BLANK
Table 6-2

PFOA, PFOS, PFBS, PFNA, and PFHxS Results in Surface Soil

Site Inspection Report, Johnstown Army Aviation Support Facility #2

Analyte OSD Screening 

Level a

Result Qual Result Qual Result Qual Result Qual Result Qual Result Qual Result Qual 

Soil, LCMSMS compliant with QSM 5.3 Table B-15 (μg/kg)PFBS 1900 ND U ND U 0.036 J ND U ND U ND U 0.040 J+ PFHxS 130 0.142 J 0.083 J 0.215 J ND U 0.264 J 0.887 J 0.254 J+ PFNA 19 0.149 J 0.133 J 0.175 J ND U 0.203 J 2.71 0.439 J+ PFOA 19 0.162 J 0.119 J 0.155 J ND U 0.324 J 2.92 0.590 J+ PFOS 13 2.04 1.78 4.06 0.063 J 6.24 7.56 1.29 J+ 

Grey Fill Detected concentration exceeded OSD Screening Levels Chemical Abbreviations

PFBS perfluorobu

References PFHxS perfluorohe

PFNA perfluoronoPFOA perfluoroocPFOS perfluorooc

Interpreted Qualifiers Acronyms and Abbreviations

J = Estimated concentration AOI Area of InteJ+ = Estimated concentration, biased high D duplicate

U = The analyte was not detected at a level greater than or equal to the adjusted DL DL detection lim

UJ = The analyte was not detected at a level greater than or equal to the adjusted DL. However, the reported adjusted DL is approximate and may be inaccurate or imprecise. ft feet

HA hand auger

Notes HQ hazard quo

ND = Analyte not detected above the LOD. LOD values are presented in Appendix F. ID identificatio

JTN JohnstownLCMSMS liquid chromLOD limit of deteND analyte not OSD Office of the QSM Quality SysQual interpreted SB soil boringUSEPA United Statμg/kg micrograms 

a. Assistant Secretary of Defense, July 2022. Risk Based Screening Levels Calculated for PFOA, PFOS, PFBS, PFHxS, and PFNA in Groundwater or Soil using USEPA’s Regional Screening Level Calculator. HQ=0.1, May 2022. Soil screening levels based on residential scenario for incidental ingestion of contaminated soil.

AOI01 

JTN-AOI01-05-HA-00-01

08/02/2022

0-1 ft

JTN-AOI01-06-HA-00

08/02/2022

0-2 ft

JTN-AOI01-03-SB-00-01

07/25/2022

0-1 ft

JTN-AOI01-04-HA-00-02

08/02/2022

0-2 ft

JTN-AOI01-01-SB-00-02-D

07/28/2022

0-2 ft

JTN-AOI01-02-SB-00-01

07/26/2022

0-1 ft

Area of Interest

Sample ID

Sample Date

Depth

JTN-AOI01-01-SB-00-02

07/28/2022

0-2 ft

AECOM 
Table 6-2

PFOA, PFOS, PFBS, PFNA, and PFHxS Results in Surface Soil

Site Inspection Report, Johnstown Army Aviation Support Facility #2

Analyte OSD Screening 

Level a

Result Qual Result Qual Result Qual Result Qual Result Qual Result Qual Result Qual 

Soil, LCMSMS compliant with QSM 5.3 Table B-15 (μg/kg)PFBS 1900 ND UJ 0.050 J ND UJ 0.041 J ND U ND U ND U PFHxS 130 0.049 J 0.463 J 0.112 J 0.166 J 0.095 J 0.622 J 0.296 J PFNA 19 0.043 J 0.370 J 0.066 J 0.057 J 0.575 J 34.9 9.36 PFOA 19 0.105 J 0.663 J 0.145 J 0.137 J 0.570 J 36.2 5.81 PFOS 13 0.127 J 1.95 1.15 0.977 J 1.05 J 439 19.4 

Grey Fill Detected concentration exceeded OSD Screening Levels Chemical Abbreviations

PFBS perfluorobu

References PFHxS perfluorohe

PFNA perfluoronoPFOA perfluoroocPFOS perfluorooc

Interpreted Qualifiers Acronyms and Abbreviations

J = Estimated concentration AOI Area of InteJ+ = Estimated concentration, biased high D duplicate

U = The analyte was not detected at a level greater than or equal to the adjusted DL DL detection lim

UJ = The analyte was not detected at a level greater than or equal to the adjusted DL. However, the reported adjusted DL is approximate and may be inaccurate or imprecise. ft feet

HA hand auger

Notes HQ hazard quo

ND = Analyte not detected above the LOD. LOD values are presented in Appendix F. ID identificatio

JTN JohnstownLCMSMS liquid chromLOD limit of deteND analyte not OSD Office of the QSM Quality SysQual interpreted SB soil boringUSEPA United Statμg/kg micrograms 

a. Assistant Secretary of Defense, July 2022. Risk Based Screening Levels Calculated for PFOA, PFOS, PFBS, PFHxS, and PFNA in Groundwater or Soil using USEPA’s Regional Screening Level Calculator. HQ=0.1, May 2022. Soil screening levels based on residential scenario for incidental ingestion of contaminated soil.

JTN-AOI02-03-HA-00-02

08/05/2022

0-2 ft

JTN-AOI02-02-SB-00-02

08/03/2022

0-2 ft 0-2 ft

JTN-AOI02-04-HA-00-02-D

07/28/2022

0-2 ft

JTN-AOI02-05-HA-00-02

08/05/2022

0-2 ft

Area of Interest

Sample ID

Sample Date

Depth

JTN-AOI02-04-HA-00-02

07/28/2022

0-2 ft

AOI02

JTN-AOI02-06-HA-00-02

08/05/2022

0-2 ft

JTN-AOI02-07-HA-00

08/05/2022

AECOM 
Table 6-2

PFOA, PFOS, PFBS, PFNA, and PFHxS Results in Surface Soil

Site Inspection Report, Johnstown Army Aviation Support Facility #2

Analyte OSD Screening 

Level a

Result Qual Result Qual Result Qual Result Qual Result Qual Result Qual Result Qual

Soil, LCMSMS compliant with QSM 5.3 Table B-15 (μg/kg)PFBS 1900 ND U ND U ND U 0.039 J+ ND UJ 0.086 J+ ND UJPFHxS 130 0.254 J 0.033 J 0.590 J ND U ND UJ 0.194 J+ ND UJPFNA 19 0.331 J 0.044 J 0.499 J 0.135 J+ 0.116 J+ 0.132 J+ 0.051 J+PFOA 19 0.575 J ND U 0.621 J 0.297 J+ 0.293 J+ 0.224 J+ ND UPFOS 13 2.55 0.313 J 11.5 1.28 J+ 0.534 J+ 1.85 J+ 0.218 J+

Grey Fill Detected concentration exceeded OSD Screening Levels Chemical Abbreviations

PFBS perfluorobu

References PFHxS perfluorohe

PFNA perfluoronoPFOA perfluoroocPFOS perfluorooc

Interpreted Qualifiers Acronyms and Abbreviations

J = Estimated concentration AOI Area of InteJ+ = Estimated concentration, biased high D duplicate

U = The analyte was not detected at a level greater than or equal to the adjusted DL DL detection lim

UJ = The analyte was not detected at a level greater than or equal to the adjusted DL. However, the reported adjusted DL is approximate and may be inaccurate or imprecise. ft feet

HA hand auger

Notes HQ hazard quo

ND = Analyte not detected above the LOD. LOD values are presented in Appendix F. ID identificatio

JTN JohnstownLCMSMS liquid chromLOD limit of deteND analyte not OSD Office of the QSM Quality SysQual interpreted SB soil boringUSEPA United Statμg/kg micrograms 

08/04/2022

0-2 ft

a. Assistant Secretary of Defense, July 2022. Risk Based Screening Levels Calculated for PFOA, PFOS, PFBS, PFHxS, and PFNA in Groundwater or Soil using USEPA’s Regional Screening Level Calculator. HQ=0.1, May 2022. Soil screening levels based on residential scenario for incidental ingestion of contaminated soil.

JTN-AOI03-03-HA-00-02

08/01/2022

0-2 ft

JTN-AOI03-01-HA-00-02

07/28/2022

0-2 ft

JTN-AOI03-02-SB-00-02

07/28/2022

0-2 ft

JTN-AOI03-06-HA-00

08/04/2022

0-2 ft

Area of Interest AOI03

Sample ID

Sample Date

Depth

JTN-AOI03-04-HA-00-02

08/04/2022

0-2 ft

08/05/2022

0-1 ft

AOI02

JTN-AOI02-09-HA-00-01 JTN-AOI03-05-HA-00-02

AECOM 
Table 6-3

PFOA, PFOS, PFBS, PFNA, and PFHxS Results in Shallow Subsurface Soil

Site Inspection Report, Johnstown Army Aviation Support Facility #2

Analyte OSD Screening 

Level a

Result Qual Result Qual Result Qual Result Qual Result Qual

PFBS 25000 ND U ND U ND UJ ND U ND UJ

PFHxS 1600 ND U ND U ND UJ ND U ND UPFNA 250 ND U ND U ND UJ ND U 0.026 J

PFOA 250 ND U ND U ND UJ ND U ND UJ

PFOS 160 ND U ND U ND UJ ND U 0.309 J

Grey Fill Detected concentration exceeded OSD Screening Levels Chemical Abbreviations

PFBS perfluorobutanesulfo

References PFHxS perfluorohexanesulfo

PFNA perfluorononanoic acPFOA perfluorooctanoic aciPFOS perfluorooctanesulfo

Interpreted Qualifiers Acronyms and Abbreviations

J = Estimated concentration AASF Army Aviation SuppoU = The analyte was not detected at a level greater than or equal to the adjusted DL AOI Area of InterestUJ = The analyte was not detected at a level greater than or equal to the adjusted DL. However, the reported adjusted DL is approximate and may be inaccurate or imprecise. D duplicate

DL detection limit

Notes ft feet

ND = Analyte not detected above the LOD. LOD values are presented in Appendix F. HQ hazard quotient

ID identificationJTN JohnstownLCMSMS liquid chromatographLOD limit of detectionND analyte not detected OSD Office of the SecretaQSM Quality Systems ManQual interpreted qualifierSB soil boringUSEPA United States Enviroμg/kg micrograms per kilog

13-15 ft

Area of Interest

Sample ID

Sample Date

Depth

JTN-AOI01-02-SB-12-14

07/26/2022

12-14 ft

Soil, LCMSMS compliant with QSM 5.3 Table B-15 (μg/kg)

a. Assistant Secretary of Defense, July 2022. Risk Based Screening Levels Calculated for PFOA, PFOS, PFBS, PFHxS, and PFNA in Groundwater or Soil using USEPA’s Regional Screening Level Calculator. HQ=0.1, May 2022. Soil screening levels based on industrial/commercial composite worker scenario for incidental ingestion of contaminated soil.

AOI01 AOI02

JTN-AOI02-02-SB-13-15-D

08/03/2022

13-15 ft

AOI03

JTN-AOI03-02-SB-13-15

08/01/2022

13-15 ft

JTN-AOI01-03-SB-10-12

07/25/2022

10-12 ft

JTN-AOI02-02-SB-13-15

08/03/2022

AECOM 
Table 6-4

PFOA, PFOS, PFBS, PFNA, and PFHxS Results in Deep Subsurface Soil

Site Inspection Report, Johnstown Army Aviation Support Facility #2

Area of Interest

Sample ID

Sample Date

Depth

Analyte Result Qual Result Qual Result Qual Result Qual Result Qual Result Qual

PFBS ND U ND UJ ND U ND U ND UJ ND UJ

PFHxS ND U ND UJ ND U ND U ND UJ ND UJ

PFNA ND U ND UJ ND U ND U ND UJ ND UJ

PFOA ND U ND UJ ND U ND U ND UJ ND UJ

PFOS ND U 0.068 J+ 0.105 J ND U ND UJ ND UJ

Interpreted Qualifiers Chemical AbbreviationsJ = Estimated concentration PFBS perfluorobutanesulfonJ+ = Estimated concentration, biased high PFHxS perfluorohexanesulfon

U = The analyte was not detected at a level greater than or equal to the adjusted DL PFNA perfluorononanoic acid

UJ = The analyte was not detected at a level greater than or equal to the adjusted DL. However, the reported adjusted DL is approximate and may be inaccurate or imprecise. PFOA perfluorooctanoic acid

PFOS perfluorooctanesulfoni

Notes

ND = Analyte not detected above the LOD. LOD values are presented in Appendix F. Acronyms and Abbreviations

AOI Area of InterestD duplicateDL detection limitft feetID identificationJTN JohnstownLCMSMS liquid chromatography LOD limit of detectionND analyte not detected aQSM Quality Systems ManuQual interpreted qualifierSB soil boringμg/kg micrograms per kilogra

07/28/2022

23-25 ft

JTN-AOI01-01-SB-30-32

07/29/2022

30-32 ft

Soil, LCMSMS compliant with QSM 5.3 Table B-15 (μg/kg)

AOI01 AOI03

JTN-AOI03-02-SB-46-48

08/01/2022

46-48 ft

JTN-AOI03-02-SB-46-48-D

08/01/2022

46-48 ft

JTN-AOI01-02-SB-25-27

07/27/2022

25-27 ft

JTN-AOI01-03-SB-15-17

07/25/2022

15-17 ft

JTN-AOI01-01-SB-23-25

AECOM 
Table 6-5

PFOA, PFOS, PFBS, PFNA, and PFHxS Results in Groundwater

Site Inspection Report, Johnstown Army Aviation Support Facility #2

Analyte OSD Screening 

Level a

Result Qual Result Qual Result Qual Result Qual Result Qual

PFBS 601 2.63 J 2.51 J 2.00 J ND U ND UPFHxS 39 22.9 21.6 ND U ND U ND U

PFNA 6 3.06 J 2.80 J ND U ND U ND U

PFOA 6 9.46 8.69 1.39 J ND U ND UPFOS 4 68.4 64.2 0.745 J ND U 1.51 J

Grey Fill Detected concentration exceeded OSD Screening Levels Chemical Abbreviations

PFBS perfluorobutanesulfo

References PFHxS perfluorohexanesulfo

PFNA perfluorononanoic acPFOA perfluorooctanoic aciPFOS perfluorooctanesulfo

Interpreted Qualifiers Acronyms and Abbreviations

J = Estimated concentration AOI Area of InterestU = The analyte was not detected at a level greater than or equal to the adjusted DL D duplicate

DL detection limit

Notes GW groundwater

ND = Analyte not detected above the LOD. LOD values are presented in Appendix F. HQ hazard quotient

ID identificationJTN JohnstownLCMSMS liquid chromatographLOD limit of detectionND analyte not detected OSD Office of the SecretaQSM Quality Systems ManQual interpreted qualifierUSEPA United States Environg/l nanogram per liter

AOI03

JTN-AOI03-MW001-GW

08/09/2022

JTN-AOI01-01-GW-D

08/05/2022

JTN-AOI01-03-GW

08/05/2022

a. Assistant Secretary of Defense, July 2022. Risk Based Screening Levels Calculated for PFOA, PFOS, PFBS, PFHxS, and PFNA in Groundwater or Soil using USEPA’s Regional Screening Level Calculator. HQ=0.1, May 2022 Groundwater screening levels based on residential scenario for direct ingestion of groundwater.

AOI01 AOI02

JTN-AOI02-02-GW

08/10/2022

Area of Interest

Sample ID

Sample Date

JTN-AOI01-01-GW

08/05/2022

Water, LCMSMS compliant with QSM 5.3 Table B-15 (ng/l)

AECOM 
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 6-13

THIS PAGE INTENTIONALLY BLANK
Bldg 230

Bldg 204

Bldg 200

Bldg 195

Bldg

288

Readiness

Center

Storage Bldg

Bldg 292

JTN-AOI01-01

JTN-AOI01-02

JTN-AOI01-03

JTN-AOI02-02

JTN-AOI03-02

Bldg 230

Bldg 204

Bldg 200

Bldg 195

Bldg

288

Readiness

Center

Storage Bldg

Bldg 292

JTN-AOI01-01

JTN-AOI01-02

JTN-AOI01-03

JTN-AOI03-02

JTN-AOI01-01

JTN-AOI01-02

JTN-AOI01-03

JTN-AOI02-01

JTN-AOI02-02 JTN-AOI02-03

JTN-AOI02-04

JTN-AOI02-05

JTN-AOI02-06

JTN-AOI02-07

JTN-AOI02-08

JTN-AOI03-01

JTN-AOI03-02

JTN-AOI03-03

JTN-AOI01-04

JTN-AOI01-05

JTN-AOI01-06 JTN-AOI02-09

JTN-AOI03-04

JTN-AOI03-05

JTN-AOI03-06

Bldg 230

Bldg 204

Bldg 200

Bldg 195

Bldg

288

Readiness

Center

Storage Bldg

Bldg 292

Legend

Estimated Facility Boundary

Facility Boundary

Roadway/Parking

12420 Milestone Center Drive

Germantown, MD 20876 Figure 6-1

PFOA Detections in Soil

12/19/2022

12/19/2022

MS 12/19/2022

ST

CM

GIS BY

CHK BY

PM

12/19/2022

CLIENT

REVISED

SCALE

PROJECT

ARNG

Site Inspection at Johnstown AASF #2, PA

Base Map: Sources: Esri, HERE, Garmin, USGS, Intermap,

INCREMENT P, NRCan, Esri Japan, METI, Esri China (Hong

1:4,500

Shallow

Intermediate

Deep

Exceedances of the OSD SL are depicted with a yellow halo.

Depth intervals shown represent respective sampling position within a given soil boring location.

0 187.5

­

375 750

Feet

PFOA Results (μg/Kg)

ND

>ND - 19

>19 - 250

>250 - 2,500

>2,500

AECOM 6-14
Bldg 230

Bldg 204

Bldg 200

Bldg 195

Bldg

288

Readiness

Center

Storage Bldg

Bldg 292

JTN-AOI01-01

JTN-AOI01-02

JTN-AOI01-03

JTN-AOI02-02

JTN-AOI03-02

Bldg 230

Bldg 204

Bldg 200

Bldg 195

Bldg

288

Readiness

Center

Storage Bldg

Bldg 292

JTN-AOI01-01

JTN-AOI01-02

JTN-AOI01-03

JTN-AOI03-02

JTN-AOI01-01

JTN-AOI01-02

JTN-AOI01-03

JTN-AOI02-01

JTN-AOI02-02 JTN-AOI02-03

JTN-AOI02-04

JTN-AOI02-05

JTN-AOI02-06

JTN-AOI02-07

JTN-AOI02-08

JTN-AOI03-01

JTN-AOI03-02

JTN-AOI03-03

JTN-AOI01-04

JTN-AOI01-05

JTN-AOI01-06

JTN-AOI02-09

JTN-AOI03-04

JTN-AOI03-05 JTN-AOI03-06

Bldg 230

Bldg 204

Bldg 200

Bldg 195

Bldg

288

Readiness

Center

Storage Bldg

Bldg 292

Legend

Estimated Facility Boundary

Facility Boundary

Roadway/Parking

12420 Milestone Center Drive

Germantown, MD 20876 Figure 6-2

PFOS Detections in Soil

12/19/2022

12/19/2022

MS 12/19/2022

ST

CM

GIS BY

CHK BY

PM

12/19/2022

CLIENT

REVISED

SCALE

PROJECT

ARNG

Site Inspection at Johnstown AASF #2, PA

Base Map: Sources: Esri, HERE, Garmin, USGS, Intermap,

INCREMENT P, NRCan, Esri Japan, METI, Esri China (Hong

1:4,500

Shallow

Intermediate

Deep

Exceedances of the OSD SL are depicted with a yellow halo.

Depth intervals shown represent respective sampling position within a given soil boring location.

0 187.5

­

375 750

Feet

PFOS Results (μg/Kg)

ND

>ND - 13

>13 - 160

>160 - 1,600

>1,600

AECOM 6-15
Bldg 230

Bldg 204

Bldg 200

Bldg 195

Bldg

288

Readiness

Center

Storage Bldg

Bldg 292

JTN-AOI01-01

JTN-AOI01-02

JTN-AOI01-03

JTN-AOI02-02

JTN-AOI03-02

Bldg 230

Bldg 204

Bldg 200

Bldg 195

Bldg

288

Readiness

Center

Storage Bldg

Bldg 292

JTN-AOI01-01

JTN-AOI01-02

JTN-AOI01-03

JTN-AOI03-02

JTN-AOI01-01

JTN-AOI01-02

JTN-AOI01-03

JTN-AOI02-01

JTN-AOI02-02 JTN-AOI02-03

JTN-AOI02-04

JTN-AOI02-05

JTN-AOI02-06

JTN-AOI02-07

JTN-AOI02-08

JTN-AOI03-01

JTN-AOI03-02

JTN-AOI03-03

JTN-AOI01-04

JTN-AOI01-05

JTN-AOI01-06

JTN-AOI02-09

JTN-AOI03-04

JTN-AOI03-05

JTN-AOI03-06

Bldg 230

Bldg 204

Bldg 200

Bldg 195

Bldg

288

Readiness

Center

Storage Bldg

Bldg 292

Legend

Estimated Facility Boundary

Facility Boundary

Roadway/Parking

12420 Milestone Center Drive

Germantown, MD 20876 Figure 6-3

PFBS Detections in Soil

12/19/2022

12/19/2022

MS 12/19/2022

ST

CM

GIS BY

CHK BY

PM

12/19/2022

CLIENT

REVISED

SCALE

PROJECT

ARNG

Site Inspection at Johnstown AASF #2, PA

Base Map: Sources: Esri, HERE, Garmin, USGS, Intermap,

INCREMENT P, NRCan, Esri Japan, METI, Esri China (Hong

1:4,500

Shallow

Intermediate

Deep

Exceedances of the OSD SL are depicted with a yellow halo.

Depth intervals shown represent respective sampling position within a given soil boring location.

0 187.5

­

375 750

Feet

PFBS Results (μg/Kg)

ND

>ND - 10

>10 - 1,900

>1,900 - 25,000

>25,000

AECOM 6-16
Bldg 230

Bldg 204

Bldg 200

Bldg 195

Bldg

288

Readiness

Center

Storage Bldg

Bldg 292

JTN-AOI01-01

JTN-AOI01-02

JTN-AOI01-03

JTN-AOI02-02

JTN-AOI03-02

JTN-AOI01-01

JTN-AOI01-02

JTN-AOI01-03

JTN-AOI03-02

Bldg 230

Bldg 204

Bldg 200

Bldg 195

Bldg

288

Readiness

Center

Storage Bldg

Bldg 292

JTN-AOI01-01

JTN-AOI01-02

JTN-AOI01-03

JTN-AOI02-01

JTN-AOI02-02

JTN-AOI02-03

JTN-AOI02-04

JTN-AOI02-05

JTN-AOI02-06

JTN-AOI02-07

JTN-AOI02-08

JTN-AOI03-01

JTN-AOI03-02

JTN-AOI03-03

JTN-AOI01-04

JTN-AOI01-05

JTN-AOI01-06

JTN-AOI02-09

JTN-AOI03-04

JTN-AOI03-05

JTN-AOI03-06

Bldg 230

Bldg 204

Bldg 200

Bldg 195

Bldg

288

Readiness

Center

Storage Bldg

Bldg

292

Legend

Estimated Facility Boundary

Facility Boundary

Roadway/Parking

12420 Milestone Center Drive

Germantown, MD 20876 Figure 6-4

PFHxS Detections in Soil

12/19/2022

12/19/2022

MS 12/19/2022

ST

CM

GIS BY

CHK BY

PM

12/19/2022

CLIENT

REVISED

SCALE

PROJECT

ARNG

Site Inspection at Johnstown AASF #2, PA

Base Map: Sources: Esri, HERE, Garmin, USGS, Intermap,

INCREMENT P, NRCan, Esri Japan, METI, Esri China (Hong

1:4,500

Shallow

Intermediate

Deep

Exceedances of the OSD SL are depicted with a yellow halo.

Depth intervals shown represent respective sampling position within a given soil boring location.

0 187.5

­

375 750

Feet

PFHxS Results (μg/Kg)

ND

>ND - 10

>10 - 130

>130 - 1,600

>1,600

AECOM 6-17
Bldg 230

Bldg 204

Bldg 200

Bldg 195

Bldg

288

Readiness

Center

Storage Bldg

Bldg 292

JTN-AOI01-01

JTN-AOI01-02

JTN-AOI01-03

JTN-AOI02-02

JTN-AOI03-02

Bldg 230

Bldg 204

Bldg 200

Bldg 195

Bldg

288

Readiness

Center

Storage Bldg

Bldg 292

JTN-AOI01-01

JTN-AOI01-02

JTN-AOI01-03

JTN-AOI03-02

JTN-AOI01-01

JTN-AOI01-02

JTN-AOI01-03

JTN-AOI02-01

JTN-AOI02-02

JTN-AOI02-03

JTN-AOI02-04

JTN-AOI02-05

JTN-AOI02-06

JTN-AOI02-07

JTN-AOI02-08

JTN-AOI03-01

JTN-AOI03-02

JTN-AOI03-03

JTN-AOI01-04

JTN-AOI01-05

JTN-AOI01-06

JTN-AOI02-09

JTN-AOI03-04

JTN-AOI03-05

JTN-AOI03-06

Bldg 230

Bldg 204

Bldg 200

Bldg 195

Bldg

288

Readiness

Center

Storage Bldg

Bldg

292

Legend

Estimated Facility Boundary

Facility Boundary

Roadway/Parking

12420 Milestone Center Drive

Germantown, MD 20876 Figure 6-5

PFNA Detections in Soil

12/19/2022

12/19/2022

MS 12/19/2022

ST

CM

GIS BY

CHK BY

PM

12/19/2022

CLIENT

REVISED

SCALE

PROJECT

ARNG

Site Inspection at Johnstown AASF #2, PA

Base Map: Sources: Esri, HERE, Garmin, USGS, Intermap,

INCREMENT P, NRCan, Esri Japan, METI, Esri China (Hong

1:4,500

Shallow

Intermediate

Deep

Exceedances of the OSD SL are depicted with a yellow halo.

Depth intervals shown represent respective sampling position within a given soil boring location.

0 187.5

­

375 750

Feet

PFNA Results (μg/Kg)

ND

>ND - 19

>19 - 250

>250 - 2,500

>2,500

AECOM 6-18
Bldg 230

Bldg 204

Bldg 200

Bldg 195

Bldg

288

Readiness

Center

Storage Bldg

Bldg 292

JTN-AOI01-01

JTN-AOI01-03

JTN-AOI02-02

JTN-AOI03-MW001

Bldg 230

Bldg 204

Bldg 200

Bldg 195

Bldg

288

Readiness

Center

Storage Bldg

Bldg 292

JTN-AOI01-01

JTN-AOI01-03

JTN-AOI02-02

JTN-AOI03-MW001

Bldg 230

Bldg 204

Bldg 200

Bldg 195

Bldg

288

Readiness

Center

Storage Bldg

Bldg 292

JTN-AOI01-01

JTN-AOI01-03

JTN-AOI02-02

JTN-AOI03-MW001

Legend

Estimated Facility Boundary

Facility Boundary

Roadway/Parking

Groundwater Flow Direction

12420 Milestone Center Drive

Germantown, MD 20876 Figure 6-6

PFOA, PFOS, and PFBS Detections 

in Groundwater

1/31/2023

1/31/2023

MS 1/31/2023

ST

CM

GIS BY

CHK BY

PM

1/31/2023

CLIENT

REVISED

SCALE

PROJECT

ARNG

Site Inspection at Johnstown AASF #2, PA

Base Map: Sources: Esri, HERE, Garmin, USGS, Intermap,

INCREMENT P, NRCan, Esri Japan, METI, Esri China (Hong

1:4,500

PFOA

PFOS

PFBS

Exceedances of the OSD SL are depicted with a yellow halo.

0 187.5

­

375 750

Feet

PFOA Results (ng/L)

ND

>ND - 6

>6 - 40

>40 - 70

>70

PFOS Results (ng/L)

ND

>ND - 4

>4 - 40

>40 - 70

>70

PFBS Results (ng/L)

ND

>ND - 100

>100 - 601

>601 - 2,000

>2,000

AECOM 6-19
Bldg 230

Bldg 204

Bldg 200

Bldg 195

Bldg 284

Bldg

288

Readiness

Center

Storage Bldg

Bldg 292

JTN-AOI01-01

JTN-AOI01-03

JTN-AOI02-02

JTN-AOI03-MW001

Bldg 230

Bldg 204

Bldg 200

Bldg 195

Bldg 284

Bldg

288

Readiness

Center

Storage Bldg

Bldg 292

JTN-AOI01-01

JTN-AOI01-03

JTN-AOI02-02

JTN-AOI03-MW001

Legend

Estimated Facility Boundary

Facility Boundary

Roadway/Parking

Groundwater Flow Direction

12420 Milestone Center Drive

Germantown, MD 20876 Figure 6-7

PFHxS and PFNA Detections

in Groundwater

12/19/2022

12/19/2022

MS 12/19/2022

ST

CM

GIS BY

CHK BY

PM

12/19/2022

CLIENT

REVISED

SCALE

PROJECT

ARNG

Site Inspection at Johnstown AASF #2, PA

Base Map: Sources: Esri, HERE, Garmin, USGS, Intermap,

INCREMENT P, NRCan, Esri Japan, METI, Esri China (Hong

1:4,500

PFHxS

PFNA

Exceedances of the OSD SL are depicted with a yellow halo.

0 187.5

­

375 750

Feet

PFHxS Results (ng/L)

ND

>ND - 39

>39 - 100

>100 - 1,000

>1,000

PFNA Results (ng/L)

ND

>ND - 6

>6 - 100

>100 - 1,000

>1,000

AECOM 6-20
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 7-1

7. Exposure Pathways

The CSMs for each AOI, revised based on the SI findings, are presented on Figure 7-1 through

Figure 7-3. Please note that while the CSM discussion 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; and

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 an incomplete 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 an 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., facility staff and visiting soldiers), construction

workers, trespassers (though unlikely due to restricted access), residents outside the facility

boundary, and recreational users outside of the facility boundary. 

7.1 Soil Exposure Pathway

The SI results in soil were used to determine whether a potentially complete pathway exists 

between the suspected source and potential receptors at AOI 1, AOI 2, and AOI 3 based on the

aforementioned criteria. 

7.1.1 AOI 1 

AOI 1 includes Building 292, Building 288, Tri-MaxTM Service Area, and hangar apron. AFFF

releases have occurred due to fire suppression system trips and testing from Building 292 and

nozzle testing, familiarization training, Tri-MaxTM servicing, and excess AFFF disposal in the apron

areas. The AFFF releases occurred on both paved areas and directly on grassy surfaces.
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 7-2

Relevant compounds were detected in surface soil and subsurface soil at AOI 1. No active 

construction was ongoing during site activities, but site workers and future construction workers

could encounter relevant compounds in surface soil via incidental ingestion and inhalation of dust.

Therefore, the surface soil exposure pathway for site workers and future construction workers are

potentially complete. The incidental ingestion and inhalation of dust exposure pathways for the 

off-facility residents and recreational users are considered incomplete due to the unlikelihood of 

those receptors encountering on-facility media. Future construction workers could encounter

relevant compounds in subsurface soil via incidental ingestion. Therefore, the subsurface soil

exposure pathway for future construction workers is potentially complete but incomplete for site 

workers who are unlikely to partake in subsurface activities. The CSM for AOI 1 is presented on

Figure 7-1. 

7.1.2 AOI 2 

AOI 2 includes the AFFF Pond and a portion of the drainage ditch that leads into a second offfacility stormwater detention pond. Surface soil samples were collected near the inlets and outlets

of these drainage features.

PFOA, PFOS, and PFNA were detected above the residential SLs in surface soil samples

collected at AOI 2. No active construction was ongoing during site activities, but site workers and

future construction workers could encounter relevant compounds in surface soil via incidental

ingestion and inhalation of dust. Therefore, the surface soil exposure pathway for site workers

and future construction workers are potentially complete. The incidental ingestion and inhalation 

of dust exposure pathways for the off-facility residents and recreational users are considered 

incomplete due to the unlikelihood of those receptors encountering on-facility media. Relevant

compounds were not detected in subsurface soil at AOI 2; therefore, all exposure pathways for

subsurface soil are considered incomplete. The CSM for AOI 2 is presented on Figure 7-2. 

7.1.3 AOI 3 

AOI 3 includes the Former Burn Area, where AFFF releases may have occurred from fire training

activities. The Former Burn Area was regraded and paved over in approximately 2010, and the

current area is a fenced motor pool. At the time of the fire training activities (approximately 2004

to 2010), AOI 3 was located on unpaved surfaces. Thus, expendedAFFF may have been released

directly onto surface soil and then infiltrated the subsurface soil. 

Relevant compounds were detected in surface soil and subsurface soil at AOI 3. No active 

construction was ongoing during site activities, but site workers and future construction workers

could come in contact with relevant compounds in surface soil via incidental ingestion and

inhalation of dust. Therefore, the surface soil exposure pathway for site workers and future

construction workers are potentially complete. The incidental ingestion and inhalation of dust 

exposure pathways for the off-facility residents and recreational users are considered incomplete 

due to the unlikelihood of those receptors encountering on-facility media. Future construction

workers could come in contact with relevant compounds in subsurface soil via incidental ingestion; 

therefore, the subsurface soil exposure pathway for future construction workers is potentially

complete but incomplete for site workers who are unlikely to partake in subsurface activities. The

CSM for AOI 3 is presented on Figure 7-3. 

7.2 Groundwater Exposure Pathway

The SI results in groundwater were used to determine whether a potentially complete pathway

exists between the suspected source and potential receptors based on the aforementioned

criteria.
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 7-3

7.2.1 AOI 1 

PFOA and PFOS were detected above their SLs in groundwater samples collected at AOI 1. 

Domestic wells are present within a 4-mile radius of the facility. Although none of the domestic

wells are immediately downgradient from AOI 1, the pathway for exposure to off-facility residents

via ingestion of groundwater is conservatively considered potentially complete. Depths to water

measured at AOI 1 in August 2022 during the SI ranged from 27.92 to 32.45 feet bgs. Based on

the measured depths to water, future construction workers and recreational users are unlikely to

encounter shallow groundwater. Therefore, the ingestion exposure pathway for future

construction workers and recreational users are considered incomplete. The ingestion exposure

pathway for site workers is also considered incomplete since the facility is serviced by municipal

water derived from surface water intakes. The CSM for AOI 1 is presented on Figure 7-1. 

7.2.2 AOI 2 

Relevant compounds were not detected in groundwater samples collected at AOI 2. Therefore,

the groundwater ingestion pathway is considered incomplete for all receptors. The CSM for AOI

2 is presented on Figure 7-2. 

7.2.3 AOI 3 

PFOS was detected below its SL at AOI 3, in the groundwater sample collected from the existing

well (JTN-AOI03-MW001). Domestic wells are present within a 4-mile radius of the facility.

Although none of the domestic wells are immediately downgradient from AOI 3, the pathway for

exposure to off-facility residents via ingestion of groundwater is conservatively considered

potentially complete. Site workers and future construction workers may also be potentially

exposed to groundwater through access to the existing well that was sampled during the SI. 

Depths to water measured at AOI 3 in August 2022 during the SI ranged from 70.35 to 119.96

feet bgs. Based on the measured depths to water, recreational users are unlikely to encounter

shallow groundwater. Therefore, the ingestion exposure pathway for recreational users is

considered incomplete. The CSM for AOI 3 is presented on Figure 7-3. 

7.3 Surface Water and Sediment Exposure Pathway

The SI results in surface water and sediment were used to determine whether a potentially

complete pathway exists between the suspected source and potential receptors at each AOI

based on the aforementioned criteria. At AOIs where surface water and sediment samples were

not collected, data from downgradient AOIs or the SI results in soil and groundwater, in

combination with knowledge of the fate and transport properties of PFAS, were used to determine

whether a potentially complete pathway exists between the suspected source and potential

receptors.

7.3.1 AOI 1 

AFFF releases from the fire suppression systems in Building 288 and Building 292 would have

been captured by trench drains within the buildings. AFFF releases on the hangar apron would

have been captured by drains on the hangar apron. All drainage is controlled by diverter valves, 

which either release the drainage as stormwater or as wastewater through connection to the

sanitary sewer. In the event that the drainage is released as stormwater, the drainage ditch and

AFFF Pond (both AOI 2) are the receiving water bodies. The surface water and sediment pathway

for AOI 1 is evaluated as part of AOI 2. The CSM for AOI 1 is presented on Figure 7-1. 
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 7-4

7.3.2 AOI 2 

Both drainage areas that comprise AOI 2, AFFF Pond and the drainage ditch, lead to Solomon

Run, which is a tributary of the Conemaugh River. Surface soil samples were collected near the

inlets and outlets of the AFFF Pond and drainage ditch.

AFFF releases from AOI 1 have a history of migrating downgradient to AOI 2, as the drainage

areas have been occasionally observed to contain residual foam after AFFF releases at AOI 1. 

PFAS are water soluble and can migrate readily from soil to surface water via leaching and runoff. Because relevant compounds were detected in soil at AOI 2, it is possible that those

compounds may have migrated from soil to surface water and sediment before ultimately

discharging as surface water off-facility. The surface water and sediment ingestion exposure

pathways for site workers, future construction workers, and recreational users are considered

potentially complete. Surface water from the Conemaugh River is not directly used as drinking 

water in the vicinity, so the surface water ingestion exposure pathway for residents is considered 

incomplete. The CSM for AOI 2 is presented on Figure 7-2. 

7.3.3 AOI 3 

Surface water runoff at AOI 3 generally flows south-southwest towards Solomon Run, which is a 

tributary of the Conemaugh River. A surface soil sample (JTN-AOI03-04) was collected near an

observed stream running south of AOI 3 and had detections of the relevant compounds. PFAS

are water soluble and can migrate readily from soil to surface water via leaching and run-off.

Because relevant compounds were detected in soil at AOI 3, it is possible that those compounds

may have migrated from soil to surface water and sediment before ultimately discharging as

surface water off-facility. The surface water and sediment ingestion exposure pathways for site

workers, future construction workers, and recreational users are considered potentially complete.

Surface water from the Conemaugh River is not directly used as drinking water in the vicinity, so 

the surface water ingestion exposure pathway for residents is considered incomplete. The CSM

for AOI 3 is presented on Figure 7-3. 
Media

SOURCE PATHWAY RECEPTOR

AOI 1

Nozzle Testing,

Familiarization

Training, AFFF

Testing and

Leaks, Excess

AFFF Disposal

Surface soil

Human

activities

Precipitation/

run-off

Leaching/

infiltration

Airborne soil

particulate

Surface soil

at AOI

Surface

water/

sediment4

Subsurface

soil

Shallow

groundwater

Source Release

Mechanism Media Transportand Migration Media ExposureRoutes

Inhalation of

dust

Ingestion

Ingestion

Ingestion

Ingestion

Human Receptors:

Current/ Future

Flow-Chart Continues

Partial/ Possible Flow

Flow-Chart Stops

Incomplete Pathway

Potentially Complete Pathway

Potentially Complete Pathway

with Exceedance of SL

/ / / /

Site 

Worker

Construction 

Worker3 Resident1,2 Trespasser/ Recreational User1

Site 

Worker

Construction 

Worker3 Resident1,2

/ / / /

/ / / /

/ / / /

/ / / /

LEGEND

Figure 7-1

Conceptual Site Model, AOI 1

Johnstown AASF #2

Potential 

Off-Facility 

Source Not 

under 

Control of 

ARNG

Trespasser/ 

Recreational User1

1. The resident and recreational users refer to offsite receptors.

2. Inhalation of dust for off-site receptors is likely

insignificant.

3. No current active construction at the facility.

4. Surface water and sediment ingestion pathway

is evaluated in AOI 2.

Notes:

Surface water and sediment ingestion pathway is

evaluated in AOI 2.

AECOM 7-5
Media

SOURCE PATHWAY RECEPTOR

AOI 2

Releases from

AOI 1 into

drainage areas

Surface

water

Human

activities

Precipitation/

run-off

Leaching/

infiltration

Airborne soil

particulate

Surface soil

at AOI

Surface

water/

sediment4

Subsurface

soil

Shallow

groundwater

Source Release

Mechanism Media Transportand Migration Media ExposureRoutes

Inhalation of

dust

Ingestion

Ingestion

Ingestion

Ingestion

Human Receptors:

Current/ Future

Flow-Chart Continues

Partial/ Possible Flow

Flow-Chart Stops

Incomplete Pathway

Potentially Complete Pathway

Potentially Complete Pathway

with Exceedance of SL

/ / / /

Site 

Worker

Construction 

Worker3 Resident1,2 Trespasser/ Recreational User1

Site 

Worker

Construction 

Worker3 Resident1,2

/ / / /

/ / / /

/ / / /

/ / / /

LEGEND

Figure 7-2

Conceptual Site Model, AOI 2

Johnstown AASF #2

Potential 

Off-Facility 

Source Not 

under 

Control of 

ARNG

Trespasser/ 

Recreational User1

1. The resident and recreational users refer to offsite receptors.

2. Inhalation of dust for off-site receptors is likely

insignificant.

3. No current active construction at the facility.

4. Includes AOI 1 evaluation for surface water

and sediment ingestion pathway.

Notes:

Includes AOI 1 evaluation for surface water and

sediment ingestion pathway.

AECOM 7-6
Media

SOURCE PATHWAY RECEPTOR

AOI 3 Fire Training Surface soil

Human

activities

Precipitation/

run-off

Leaching/

infiltration

Airborne soil

particulate

Surface soil

at AOI

Surface

water/

sediment

Subsurface

soil

Shallow

groundwater

Source Release

Mechanism Media Transportand Migration Media ExposureRoutes

Inhalation of

dust

Ingestion

Ingestion

Ingestion

Ingestion

Human Receptors:

Current/ Future

Flow-Chart Continues

Partial/ Possible Flow

Flow-Chart Stops

Incomplete Pathway

Potentially Complete Pathway

Potentially Complete Pathway

with Exceedance of SL

/ / / /

Site 

Worker

Construction 

Worker3 Resident1,2 Trespasser/ Recreational User1

Site 

Worker

Construction 

Worker3 Resident1,2

/ / / /

/ / / /

/ / / /

/ / / /

LEGEND

Figure 7-3

Conceptual Site Model, AOI 3

Johnstown AASF #2

Potential 

Off-Facility 

Source Not 

under 

Control of 

ARNG

Trespasser/ 

Recreational User1

1. The resident and recreational users refer to offsite receptors.

2. Inhalation of dust for off-site receptors is likely

insignificant.

3. No current active construction at the facility.

Notes:

AECOM 7-7
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 7-8

THIS PAGE INTENTIONALLY BLANK
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 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 SI Activities

The SI field activities were conducted from 21 July to 10 August 2022 and consisted of utility

clearance, borings, soil sample collection, permanent monitoring well installation and development,

groundwater sample collection, and land surveying. Field activities were conducted in accordance

with the SI QAPP Addendum (AECOM, 2021), except as noted in Section 5.8. 

To fulfill the project DQOs set forth in the approved SI QAPP Addendum (AECOM, 2021), samples

were collected and analyzed for a subset of 18 compounds by LC/MS/MS compliant with QSM 5.3

Table B-15 as follows. 

• Thirty (30) soil samples from five (5) borings and sixteen (16) hand auger locations;

• Four (4) groundwater samples from three (3) permanent well locations and one (1) existing

well (JTN-AOI03-MW001);

• Fifteen (15) QA/QC 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 no further action is

required. Additionally, the CSMs were refined to assess whether a potentially complete pathway

exists between the suspected 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 under CERCLA is warranted in an RI for AOI 1 

and AOI 2; no further evaluation is warranted for AOI 3 at this time (see Table 8-1). Based on the

CSMs developed and revised in light of the SI findings, there is potential for exposure to drinking

water receptors from AOI 1 from suspected sources on the facility resulting from historical DoD

activities. Sample analytical concentrations collected during the SI were compared to the project

SLs in soil and groundwater, as described in Table 6-1. A summary of the results of the SI data

relative to the SLs is as follows: 

• At AOI 1:

• The detected concentrations of relevant compounds in surface and subsurface soil

at AOI 1 were below their respective SLs.

• PFOA and PFOS in groundwater exceeded their SLs. PFOA exceeded the SL of 6

ng/L with a maximum concentration of 9.46 ng/L. PFOS exceeded the SL of 4 ng/L

with a maximum concentration of 68.4 ng/L.

• Based on the results of the SI, further evaluation of AOI 1 is warranted in an RI.
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• At AOI 2:

• PFOA, PFOS, and PFNA were detected in surface soil, at concentrations above their

residential SLs. PFOA exceeded the SL of 19 μg/kg, with a concentration of 36.2

μg/kg in JTN-AOI02-06. PFOS exceeded the SL of 13 μg/kg, with concentrations 439

μg/kg and 19.4 μg/kg in JTN-AOI02-06 and JTN-AOI02-07, respectively. PFNA

exceeded the SL of 19 μg/kg, with a concentration of 34.9 μg/kg in JTN-AOI02-06.

• No relevant compounds were detected in groundwater at AOI 2.

• Based on the results of the SI, further evaluation of AOI 2 is warranted in an RI.

• At AOI 3:

• The detected concentrations of relevant compounds in surface and subsurface soil

at AOI 3 were below their respective SLs.

• PFOS was detected in groundwater below the SL. No other relevant compounds

were detected in groundwater at AOI 3.

• Based on the results of the SI, no further evaluation of AOI 3 is warranted.

This report resulted in one location (existing well JTN-AOI03-MW001) with groundwater data 

associated with the Former Burn Area at AOI 3. Another permanent well (JTN-AOI03-02) was 

installed at AOI 3, but the well was purged dry and could not be sampled for groundwater. All 

sample concentration data at AOI 3 were measured below the respective SLs. One surface soil 

sample collected from JTN-AOI03-02 had a PFOS concentration of 11.5 μg/kg close to the 

residential SL of 13 μg/kg. Based on the lack of groundwater data and AOI 3’s downgradient 

position with respect to AOI 1 and AOI 2, additional sampling at AOI 3 may be considered during 

future phases of CERCLA. For that reason, AOI 3 is recommended for no further action at this 

time, with consideration for additional sampling during a future CERCLA phase.

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. 

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 Future Action

1 Hangar Apron

Areas Proceed to RI

2 Drainage Areas Proceed to RI

3 Former Burn

Area

No further action

at this time

Legend:

 = detected; exceedance of the screening levels

 = detected; no exceedance of the screening levels

 = not detected
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9. References

AECOM. 2018a. Final Site Inspection Programmatic Uniform Federal Policy-Quality Assurance 

Project Plan, Perfluorooctane Sulfonic Acid (PFOS) and Perfluorooctanoic Acid (PFOA)

Impacted Sites ARNG Installations, Nationwide Contract No. W912DR-12-D-0014/

W912DR17F0192. 9 March.

AECOM. 2018b. Final Programmatic Accident Prevention Plan, Perfluorooctane Sulfonic Acid

(PFOS) and Perfluorooctanoic Acid (PFOA) Impacted Sites ARNG Installations, Nationwide

Contract No. W912DR-12-D-0014/W912DR17F0192. July.

AECOM. 2020. Final Preliminary Assessment Report, Johnstown Army Aviation Support Facility

#2, Johnstown, Pennsylvania. July.

AECOM. 2021. Final Site Inspection Uniform Federal Policy-Quality Assurance Project Plan

Addendum, Johnstown Army Aviation Support Facility #2, Johnstown, Pennsylvania, 

Perfluorooctanesulfonic Acid (PFOS) and Perfluorooctanoic Acid (PFOA) Impacted Sites

ARNG Installations, Nationwide. December. 

AECOM. 2022. Final Site Safety and Health Plan, Johnstown Army Aviation Support Facility #2, 

Johnstown, Pennsylvania, Perfluorooctanesulfonic Acid (PFOS) and Perfluorooctanoic Acid

(PFOA) Impacted Sites ARNG Installations, Nationwide. July. 

AMEC, 2003. Final Environmental Assessment of Changes in Helicopter Operations by the

Pennsylvania Army National Guard at Johnstown Cambria County Airport, Johnstown,

Pennsylvania. February. 

Army Public Health Center, 2018. Pennsylvania Army National Guard Installation Compatible Use

Zone Study. December.

Assistant Secretary of Defense. 2022. Investigation Per- and Polyfluoroalkyl Substances within

the Department of Defense Cleanup Program. United States Department of Defense.

6 July. 

Cecil, C. B., Brezinski, D. K., DuLong, F. 2004. The Palezoic record of changes in global climate

and sea level: Central Appalachian basin. US Geological Survey Circular.

Commonwealth of Pennsylvania, 2018. Physiographic Provinces of Pennsylvania.

http://www.docs.dcnr.pa.gov/cs/groups/public/documents/document/dcnr_016202.pdf?_sm_a

u_=iVVt1rjsP0fRRvZPkMMGvK6FH3tTM (Accessed October 2019). 

DA. 2018. Army Guidance for Addressing Releases of Per- and Polyfluoroalkyl Substances.

4 September.

DoD. 2019a. Department of Defense (DoD), Department of Energy (DOE) Consolidated Quality

Systems Manual (QSM) for Environmental Laboratories, Version 5.3. 

DoD. 2019b. General Data Validation Guidelines. Environmental Data Quality Workgroup. 

4 November.

Guelfo, J.L. and Higgins, C.P. 2013. Subsurface Transport Potential of Perfluoroalkyl Acids at

Aqueous Film-Forming Foam (AFFF)-Impacted Sites. Environmental Science and Technology

47(9): 4164-71.

Higgins, C.P., and Luthy, R.G. 2006. Sorption of perfluorinated surfactants on sediments. 

Environmental Science and Technology 40 (23): 7251-7256.
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

AECOM 9-2

Highland Sewer and Water Authority, 2019. Where Does Your Water Come From.

https://www.highlandwater.net/where-your-water-comes-from (Accessed October 2019). 

ITRC. 2018. Environmental Fate and Transport for Per- and Polyfluoroalkyl Substances. March. 

McElroy, T. A. 1993. Geologic Map of Cambria County, Pennsylvania, Showing the Locations of

Selected Wells and Springs. 

National Park Service, 2018. Geologic Map of Johnstown Flood National Memorial, Pennsylvania.

https://irma.nps.gov/DataStore/DownloadFile/603761 (Accessed October 2019).

National Weather Service, 2019. Climatological Report (Annual), State College PA. 

https://w2.weather.gov/climate/getclimate.php?wfo=ctp (Accessed October 2019). 

Pennsylvania Department of Conservation & Natural Resources, n.d. Pennsylvania Groundwater

Information System. 

(https://www.dcnr.pa.gov/Conservation/Water/Groundwater/PAGroundwaterInformationSyste

m/Pages/default.aspx) (Accessed January 2023). 

Phalen, W.C. and Martin, L., 1911. Mineral Resources of Johnstown, Pennsylvania and Vicinity.

United States Geological Survey Bulletin 447.

Skelly and Loy, Inc., 2010. Final Environmental Condition of Property Environmental Site

Assessment, Johnstown Army Aviation Support Facility, Richland and Conemaugh Townships,

Cambria Coun20ty, Pennsylvania. January.

Southwestern Cambria County Water Authority, 2018. 2018 Annual Drinking Water Quality

Report, PWSID #4110041.

https://goh2o.net/sites/default/files/files/129/10984/swcambriacountyccr2018.pdf?reload=May

-23-2019_12-27-28-pm (Accessed May 2020). 

USACE. 2016. Technical Project Planning Process, EM-200-1-2. 26 February.

USACHPPM. 2006. Pennsylvania Army National Guard Operational Noise Management Plan.

January. 

USEPA. 1980. Comprehensive Environmental Response, Compensation, and Liability Act

(CERCLA). 

USEPA. 1994. National Oil and Hazardous Substances Pollution Contingency Plan (Final Rule). 

40 CFR Part 300; 59 Federal Register 47384. September.

USEPA. 2001. Risk Assessment Guidance for Superfund, Volume I: Human Health Evaluation

Manual (Part D, Standardized Planning, Reporting, and Review of Superfund Risk

Assessments). December.

USEPA. 2017. National Functional Guidelines for Organic Superfund Data Review. OLEM

9355.0-136, EPA-540-R-2017-002. Office of Superfund Remediation and Technology

Innovation. January.

USFWS. 2022. Species by County Report, County: Cambria, Pennsylvania. Environmental

Conservation Online System. Accessed 20 December 2022 at

https://ecos.fws.gov/ecp/report/species-listings-by-current-range-county?fips=42021. 

US Geological Survey. 1997. Ground Water Atlas of the United States, Delaware, Maryland, New 

Jersey, North Carolina, Pennsylvania, Virginia, West Virginia HA 730-L. 
Site Inspection Report

Johnstown AASF #2, Johnstown, Pennsylvania

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Xiao, F., Simcik, M. F., Halbach, T. R., and Gulliver, J. S. 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. 
Site Inspection Report

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