FINAL

Site Inspection Report 

Army Aviation Support Facility 1

Green Township, Summit

County, Ohio

Perfluorooctanesulfonic Acid (PFOS) and 

Perfluorooctanoic Acid (PFOA) Impacted Sites

ARNG Installations, Nationwide

December 2022

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 ...............................................................................................2-1

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

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

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

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

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

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

3.1 AOI 1.......................................................................................................................3-1

3.1.1 Storage and Ramp Area ...............................................................................3-1

3.2 AOI 2.......................................................................................................................3-1

3.2.1 Green AASF1 Hangar...................................................................................3-1

3.3 AOI 3.......................................................................................................................3-2

3.3.1 Wetland ........................................................................................................3-2

4. Project Data Quality Objectives .....................................................................................4-1

4.1 Problem Statement .................................................................................................4-1

4.2 Goals of the Study ..................................................................................................4-1

4.3 Information Inputs ...................................................................................................4-2

4.4 Study Boundaries ...................................................................................................4-2

4.5 Analytical Approach ................................................................................................4-2

4.6 Data Usability Assessment .....................................................................................4-3

4.6.1 Precision.......................................................................................................4-3

4.6.2 Accuracy.......................................................................................................4-4

4.6.3 Representativeness......................................................................................4-5

4.6.4 Comparability................................................................................................4-6

4.6.5 Completeness...............................................................................................4-6

4.6.6 Sensitivity .....................................................................................................4-6

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 PFAS Sampling Equipment Acceptability .......................5-2

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

5.3 Temporary Well Installation and Groundwater Grab Sampling ...............................5-3

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

5.5 Surveying................................................................................................................5-4

5.6 Investigation-Derived Waste ...................................................................................5-4
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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

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

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

6.3.2 AOI 1 Groundwater Analytical Results .........................................................6-2

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

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

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

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

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

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

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

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

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

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 ............................................................................................................7-2

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

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

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

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

8.2 SI Goals Evaluation ................................................................................................8-1

8.3 Outcome .................................................................................................................8-2

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

Appendix A Data Validation Reports

Appendix B Field Documentation

B1. Log of Daily Notice of Field Activities

B2. Sampling Forms

B3. Survey Data

B4. Investigation-Derived Waste Logs

B5. Non-Conformance and Corrective Action Reports

Appendix C Photographic Log

Appendix D Laboratory Reports

Appendix E Boring Logs 

Appendix F Analytical Results

Figures

Figure 2-1 Facility Location

Figure 2-2 Facility Topography

Figure 2-3 Groundwater Features

Figure 2-4 Groundwater Elevation Contours

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 PFOA, PFOS, and PFBS 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

Table ES-3 Site Inspection Recommendations

Table 5-1 Site Inspection Samples by Medium

Table 5-2 Soil Boring Depths, Temporary Well Screen Intervals, and Groundwater 

Elevations

Table 6-1 Screening Levels (Soil and Groundwater)

Table 6-2 PFAS Detections in Surface Soil

Table 6-3 PFAS Detections in Subsurface Soil

Table 6-4 PFAS Detections in Groundwater

Table 8-1 Summary of Site Inspection Findings

Table 8-2 Site Inspection Recommendations
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Acronyms and Abbreviations

% percent

°C degrees Celsius

°F degrees Fahrenheit

μg/kg micrograms per kilogram

6:2 FTS 6:2 Fluorotelomer sulfonic acid

8:2 FTS 8:2 Fluorotelomer sulfonic acid

AECOM AECOM Technical Services, Inc.

AFFF aqueous film forming foam

AOI Area of Interest

ARNG Army National Guard

bgs below ground surface 

CCV Calibration verification

CERCLA Comprehensive Environmental Response, Compensation, and Liability Act 

CoC chain of custody

CSM conceptual site model

DA Department of the Army

DERR Division of Environmental Response and Revitalization

DO dissolved oxygen

DoD Department of Defense

DPT direct push technology

DQI data quality indicator

DQO data quality objective

DUA data usability assessment

DVR data validation report 

EIS extraction internal standards

ELAP Environmental Laboratory Accreditation Program

EM Engineer Manual

ERB equipment rinsate blank

FedEx Federal Express

FRB field reagent blank

gpm gallons per minute

GPRS Ground Penetrating Radar Services, LLC

HA Health Advisory

HEF high expansion foam

HDPE high-density polyethylene 

IDW investigation-derived waste

IIS injection internal standards

ITRC Interstate Technology Regulatory Council

LC/MS/MS liquid chromatography with tandem mass spectrometry

LCS laboratory control spike

LCSD laboratory control spike duplicate

LOQ limit of quantitation

MDL method detection limit
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MS matrix spike

MSD matrix spike duplicate

NELAP National Environmental Laboratory Accreditation Program

NEtFOSAA N-ethyl perfluorooctanesulfonamidoacetic acid

ng/L nanograms per liter

NMeFOSAA N-methyl perfluorooctanesulfonamidoacetic acid

NOAA National Oceanic and Atmospheric Administration

NOSC Navy Operational Support Center

ODGS Ohio Division of Geological Survey

ODNR Ohio Department of Natural Resources

OHANG Ohio Air National Guard

OHARNG Ohio Army National Guard

Ohio EPA Ohio Environmental Protection Agency

ORP oxidation-reduction potential

OSD Office of the Secretary of Defense

PA Preliminary Assessment

PFAS per- and polyfluoroalkyl substances

PFBA perfluorobutyrate

PFBS perfluorobutanesulfonic acid

PFDA perfluorodecanoic acid

PFDoA perfluorododecanoic acid

PFHpA perfluoroheptanoic acid

PFHxA perfluorohexanoic acid

PFHxS perfluorohexanesulfonic acid

PFNA perfluorononanoic acid

PFOA perfluorooctanoic acid

PFOS perfluorooctanesulfonic acid

PFPeA perfluoropentanoic acid

PFTeDA perfluorotetradecanoic acid

PFTrDA perfluorotridecanoic acid

PFUdA perfluoroundecanoic 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

RPD relative percent differences

SI Site Inspection

SL screening level

SOP standard operating procedure

TCRA Time Critical Removal Action

TOC total organic carbon
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TPP Technical Project Planning

UCMR Unregulated Contaminant Monitoring Rule

UFP Uniform Federal Policy

US United States

USACE United States Army Corps of Engineers

USCS Unified Soil Classification System

USEPA United States Environmental Protection Agency

USFWS United States Fish and Wildlife Service
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Executive Summary

The Army National Guard (ARNG) G9 is performing Preliminary Assessments (PAs) and Site 

Inspections (SIs) at per- and polyfluoroalkyl substances (PFAS)-impacted sites at ARNG facilities 

nationwide. The objective of the SI at each facility is to identify whether there has been a release 

to the environment from the Areas of Interest (AOIs) identified in the PA and determine the 

presence or absence of perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), and 

perfluorobutanesulfonic acid (PFBS) at or above screening levels (SLs). An SI was completed at

the Army Aviation Support Facility 1 (AASF1) in Green Township, Summit County, Ohio. The 

Green AASF1 will also be referred to as the “facility” throughout this document.

Green AASF1 is located at 6000 W Airport Dr, North Canton, Ohio 44720. The facility is home to 

the 238th Aviation Regiment and is located in Green Township, Summit County, Ohio, on the north

portion of the Akron-Canton Regional Airport. The property is leased by the State of Ohio, Adjutant 

General’s Department from the Akron-Canton Airport. The facility currently has an AASF building, 

an aviation support area, helicopter parking area, vehicle maintenance area, and an armory. 

Hover operations and other flight training activities occur on and near the helicopter pad. 

Three potential PFAS release areas were identified at Green AASF1 during the PA: the Storage 

and Ramp Area, the Green AASF1 Hangar, and the Wetland (AECOM, 2020). Green AASF1 

includes a hangar equipped with a high expansion foam (HEF) fire suppression system. Tri-MaxTM

tanks were previously stored in the hangar before transferring to the outdoor storage area. A test 

of the HEF suppression system occurred, resulting in a full release of the system. Tri-MaxTM tanks 

containing aqueous film forming foam were stored outside of Green AASF1 Building 5 (cold 

storage area) and on the ramp area. Unintentional releases from the tanks may have occurred at 

these locations. The close proximity of potential releases in the Green AASF1 Hangar and 

Storage and Ramp Area, coupled with surface water flow to the east, leaves the potential for 

migrating PFAS the third potential release area, the Wetland. These three potential PFAS release 

areas were grouped into three Areas of Interest (AOIs), which were investigated during the SI. 

The SI field activities were conducted from 16 to 18 June 2021 and included the collection of soil 

and groundwater samples.

To fulfill the project Data Quality Objectives set forth in the approved SI Quality Assurance Project 

Plan Addendum (AECOM, 2021a), samples were collected and analyzed for a subset of 18 PFAS 

by liquid chromatography with tandem mass spectrometry compliant with Quality Systems Manual 

5.3 Table B-15. The 18 PFAS analyzed as part of the ARNG SI program are specified in Section 

5.9 of this Report.

The Department of Defense (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 Office 

of the Secretary of Defense (OSD) dated 15 September 2021 (Assistant Secretary of Defense, 

2021). 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 and there is a release identified that is likely attributed to ARNG activities, the AOI

will proceed to the next phase under CERCLA. The SLs established in the OSD memorandum 

apply to three compounds: PFOS, PFOA, and PFBS. 

The SLs are presented on Table ES-1 below. All other results presented in this report are 

considered informational in nature and serve as an indication as to whether soil and groundwater

contain or do not contain the 18 PFAS analyzed within the boundaries of the facility.

Sample chemical analytical concentrations were compared against the project SLs as described 

in Table ES-1. A summary of the results of the SI data relative to the SLs is as follows:
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• At AOI 1, detected concentrations of PFOA, PFOS, and PFBS in groundwater at the 

Storage and Ramp potential PFAS release area were below their respective SLs. Based 

on the results of the SI, no further evaluation of AOI 1 is warranted.

• At AOI 2, detected concentrations of PFOA, PFOS, and PFBS in groundwater at the Green 

AASF1 Hangar potential PFAS release area were below their respective SLs. Based on 

the results of the SI, no further evaluation of AOI 2 is warranted.

• At AOI 3, detected concentrations of PFOA, PFOS, and PFBS in groundwater at the

Wetland potential PFAS release area were below their respective SLs. Based on the 

results of the SI, no further evaluation of AOI 3 is warranted.

• The detected concentrations of PFOA, PFOS, and PFBS in soil at all AOIs were below the

SLs. 

Table ES-2 summarizes the SI results for soil and groundwater. Based on the conceptual site 

models (CSMs) developed and revised in light of the SI findings, there is potential for exposure 

to drinking water receptors caused by DoD activities at or adjacent to the facility.

Table ES-3 summarizes the rationale used to determine if an AOI should be considered for further 

investigation under CERCLA and undergo an RI. Based on the results of this SI, no further 

evaluation is warranted for AOI 1: Storage and Ramp Area, AOI 2: Green AASF1 Hangar, and 

AOI 3: Wetland.
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Table ES-1: Screening Levels (Soil and Groundwater) 

Analyte

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,b

PFOA 130 1,600 40

PFOS 130 1,600 40

PFBS 1,900 25,000 600

Notes:

a.) Assistant Secretary of Defense, 2021. Risk Based Screening Levels Calculated for PFOS, PFOA, PFBS in Groundwater and Soil using 

United States Environmental Protection Agency’s (USEPA’s) Regional Screening Level Calculator. Hazard Quotient (HQ) = 0.1. 15 

September 2021. 

b.) USEPA. 2016a. Drinking Water Health Advisory (HA) for Perfluorooctanoic Acid (PFOA). Office of Water (4304T). Health and Ecological 

Criteria Division, Washington, DC 20460. USEPA Document Number: 822-R-16-005. May 2016. / USEPA. 2016b. Drinking Water HA for 

Perfluorooctane Sulfonic Acid (PFOS). Office of Water (4304T). Health and Ecological Criteria Division, Washington, DC 20460. USEPA 

Document Number: 822-R-16-004. May 2016.

Table ES-2: Summary of Site Inspection Findings

AOI Potential PFAS 

Release Area

Soil – 

Source Area

Groundwater – 

Source Area

Groundwater –

Facility Boundary

1 Storage and Ramp 

Area

2 Green AASF1 

Hangar

N/A

3 Wetland

Legend:

N/A = not applicable 

= PFOA, PFOS, and/or PFBS detected; exceedance of the screening levels

= PFOA, PFOS, and/or PFBS detected; no exceedance of the screening levels

= PFOA, PFOS, and PFBS not detected

Table ES-3: Site Inspection Recommendations

AOI Description Rationale Future Action

1 Storage and Ramp 

Area

Detections in groundwater but no 

exceedances of SLs. No exceedances of 

SLs in soil.

No further action

2 Green AASF1 

Hangar

Detections in groundwater but no 

exceedances of SLs. No exceedances of 

SLs in soil.

No further action

3 Wetland

Detections in groundwater but no 

exceedances of SLs. No exceedances of 

SLs in soil.

No further action
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1. Introduction

1.1 Project Authorization

The Army National Guard (ARNG) G9 is the lead agency in performing Preliminary Assessments 

(PAs) and Site Inspections (SIs) for Perfluorooctanesulfonic acid (PFOS) and Perfluorooctanoic 

acid (PFOA) at Impacted Sites, ARNG Installations, Nationwide. This work is supported by the 

United States (US) Army Corps of Engineers (USACE) Baltimore District and their contractor, 

AECOM Technical Services, Inc. (AECOM), under Contract Number W912DR-12-D-0014, Task 

Order W912DR17F0192, issued 11 August 2017. The ARNG performed this SI at Army Aviation 

Support Facility 1 (AASF1) in Green Township, Summit County, Ohio. The Green AASF1 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; 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 including specific 

requirements for sampling for PFOA, PFOS, and perfluorobutanesulfonic acid (PFBS), and the 

group of related compounds known in the industry as per- and polyfluoroalkyl substances (PFAS). 

The term PFAS is used throughout this report to encompass all PFAS chemicals being evaluated, 

including PFOA, PFOS, and PFBS, which are the key components of the suspected releases 

being evaluated, and the other 15 related compounds listed in the task order.

1.2 SI Purpose

A PA was performed at Green AASF1 (AECOM, 2020) that identified three potential PFAS release 

areas at the facility, which were grouped into three Areas of Interest (AOIs). The objective of the 

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

the presence or absence of PFOA, PFOS, and PFBS at or above screening levels (SLs).

As stated in the Federal Facilities Remedial Site Inspection Summary Guide (USEPA, 2005), an 

SI has five goals: 

1. Develop information to potentially eliminate a release from further consideration because 

it is determined that it poses no significant threat to human health or the environment;

2. Determine the potential need for a removal action;

3. Collect or develop data to evaluate potential release;

4. Collect data to better characterize the release for more effective and rapid initiation of a 

Remedial Investigation (RI), if determined necessary; and

5. Collect data to determine whether the release is more than likely the result of activities 

associated with the Department of Defense (DoD).

In addition to the USEPA-identified goals of an SI, the ARNG SI also identifies whether there are 

potential off-facility PFAS sources. 
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2. Facility Background

2.1 Facility Location and Description

Green AASF1 is located at 6000 W Airport Dr, North Canton, Ohio 44720. The facility is home to 

the 238th Aviation Regiment and is located in Green Township, Summit County, Ohio, on the north 

portion of the Akron-Canton Regional Airport (Figure 2-1). The property is leased by the State of 

Ohio, Adjutant General’s Department from the Akron-Canton Airport, and the lease applies to the 

Ohio ARNG (OHARNG). The facility currently has an AASF building, an aviation support area, 

helicopter parking area, vehicle maintenance area, and an armory. Hover operations and other 

flight training activities occur on and near the helicopter pad. 

2.2 Facility Environmental Setting

Green AASF1 is located in the Appalachian Highlands region of Ohio. The Appalachian Highlands 

encompass the eastern part of the state and are characterized by alternating plateaus and plains 

and a higher relief than the adjacent Interior Plains. The terrain around the facility exhibits 

moderate to low relief (Figure 2-2). The elevation of the facility is approximately 1,215 feet above 

mean sea level. The facility is surrounded by farmland and deciduous forest to the north and west, 

the Akron-Canton Regional Airport to the southeast, and residential areas to the west.

2.2.1 Geology

Green AASF1 lies within the Appalachian Plateaus physiographic province, Akron-Canton 

Interlobate Plateau district. The facility occupies a hummocky area between two converging 

glacial lobes and is dominated by kames, kame terraces, eskers, kettles, kettle lakes, bogs, and 

fens (Ohio Division of Geological Survey [ODGS], 1998).

Green AASF1 is situated on sandy Wisconsinan-age clay to loam glacial till (ODGS, 1998). The 

glacial till unit is generally 21 to 50 feet thick and may be up to 80 feet thick locally (ODGS, 2004). 

The glacial till is underlain by shale and siltstone bedrock of the Allegheny and Pottsville Groups. 

The shale and siltstone are interbedded with minor very fine- to medium-grained sandstone and 

minor limestone. Incidental coal beds up to 12 feet thick may occur locally. The Allegheny and 

Pottsville Groups are up to 700 feet thick (Figure 2-3) (Slucher, E.R. et al., 2006).

Soil borings completed during the SI found well-graded sand, clay, and clayey sand as the 

dominant lithology of the soils below Green AASF1; the borings were completed at depths 

between 10 and 25 feet below ground surface (bgs). Below the first layers of sand, the lithology 

was predominantly clays, including fat clay, lean clay, and clayey sand. The clay layers extended 

the length of the boring. Some borings included sections of gravel in the deeper sandy layers. 

Samples for grain size analyses were collected at four locations, AOI01-01, AOI02-01, AOI03-03, 

and ESLR-01, and analyzed via American Society for Testing and Materials Method D-422. The 

results indicate that the soil samples are comprised primarily of silt (57.15 percent [%] to 75.94%) 

and clay (19.96% to 40.86%). These results and facility observations are consistent with the 

understood geologic environment of the area. Boring logs are presented in Appendix E, and grain 

size results are presented in Appendix F.

2.2.2 Hydrogeology

Green AASF1 is located in the Appalachian Plateaus aquifer system. The aquifer system has two 

major hydrogeologic units within the vicinity of Green AASF1: (1) the surficial aquifer system and 

(2) the Pennsylvanian aquifers. The surficial aquifers consist of glacial or alluvial sand and gravel 

deposits surrounded by low-permeability glacial till and are concentrated in stream valleys. Yields 
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from the surficial aquifer are typically low in the vicinity of Green AASF1 and increase westward 

towards Singer Lake and Nimisila Reservoir. The Pennsylvanian aquifer is composed primarily of 

sandstone and shale from the Allegheny and Pottsville Groups. Yields from the sandstone and 

shale are generally three to ten gallons per minute (gpm). Yields as much as 50 gpm have been 

obtained from the Sharon conglomerate member of the Allegheny and Pottsville Groups at depths 

greater than 100 feet bgs (Schmidt, 1979).

The property is located on a groundwater divide in both the surficial aquifer system and the 

Pennsylvanian aquifers. Groundwater in the eastern part of the property flows east, towards a 

tributary of the West Branch of Nimishillen Creek; groundwater in the western part of the property 

flows west, southwest, and northwest toward a tributary of Nimisila Creek (Figure 2-3). Based on 

monitoring well data from the Ohio Water Wells database, the depth to water in the immediate 

vicinity of Green AASF1 is estimated to be between 15 to 30 feet bgs (Ohio Department of Natural 

Resources [ODNR], 2020). 

Domestic, industrial, public/semi-public, agricultural/irrigation, and monitoring wells are located 

within 4 miles of the facility (Figure 2-3). A query of the Ohio Water Wells database showed 

several private drinking water wells within a 0.5 mile radius of the facility, as well as one 

public/semi-public supply well on the property. According to the ODNR, the well (well log number 

788781) was installed in 1996 to a depth of 360 feet bgs into the sandstone aquifer; however, 

interviewees confirmed that this drinking water well has been inactive for approximately 10 years 

(ODNR, 2018). Drinking water within the facility is now provided by Aqua Ohio, a public water 

utility provider and a subsidiary of Aqua America. Aqua Ohio serves multiple counties and receives 

the drinking water it distributes from groundwater and a series of surface water locations at Evans, 

Pine, Hamilton, and McKelvey Lakes and Lake Erie (Aqua, 2018). The adjacent Akron-Canton 

Regional Airport drinking water supplies are provided by the city of North Canton, located about 

3.5 miles south. Drinking water from the city of North Canton is supplied by a series of six 

groundwater drinking wells in and around the North Canton area.

The Unregulated Contaminant Monitoring Rule (UCMR) sampling program was an addition to the 

1996 Safe Drinking Water Act which requires every five years the USEPA issue a new list of no 

more than 30 unregulated contaminants to be monitored by public water systems. PFAS was 

added as part of the UCMR 3 list (USEPA, 2017a). The UCMR 3 dataset was evaluated to 

determine which public water systems were sampled for PFAS within a 20-mile radius of the 

facility. Based on this rule, the City of North Canton public drinking water was sampled. The 

sampling results for PFOA and PFOS were non-detect. No other public water system within 20 

miles of the facility had detections of PFOA or PFOS (USEPA, 2017a). PFAS analyses performed 

in 2016 had method detection limits (MDLs) that were higher than currently achievable. Thus, it 

is possible that low concentrations of other PFAS were not detected during the UCMR 3 but might 

be detected if analyzed today.

Depths to water measured in June 2021 during the SI ranged from 2.27 to 18.31 feet bgs. 

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

groundwater flow direction is generally to the east. 

2.2.3 Hydrology

Regional surface water features include Willowdale Lake to the southwest, the Nimisila Reservoir 

to the west, and the Portage Lakes to the northwest. The Nimisila Reservoir is used to maintain 

a constant water supply in the Portage Lakes, and surface water is withdrawn from the Portage 

Lakes for industrial use.

No surface water flows onto Green AASF1. Three streams flow to the east, west, and north of the 

facility, respectively (Figure 2-5). An unnamed tributary of the West Branch of Nimishillen Creek 

begins approximately 2,000 feet from the eastern boundary of the facility and flows to the 
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southeast. An unnamed tributary of Nimisila Creek begins approximately 2,800 feet from the 

western boundary of the facility and flows to the south/southwest for approximately 2.5 miles, 

where it enters Willowdale Lake. An unnamed stream flowing to the north begins approximately 

1,800 feet from the northern boundary of the facility. Lake Cable, a popular lake for recreational 

activities, is located approximately four miles south of Green AASF1. Recreational use of nearby 

surface water bodies, including Willowdale Lake, Lake Cable, and other surrounding tributaries is 

high. 

Three small forested/shrub wetlands are located within and directly surrounding the facility 

boundary. Two wetland areas are located outside the southeast boundary of the facility; one 

wetland is located outside the northeast corner of the facility boundary, and one wetland is located 

on the southeastern edge of the facility (CHA, 2015). An approximately 18.4-acre forested/shrub 

wetland begins approximately 930 feet from the north property boundary and drains into the 

unnamed stream to the north of the facility. Surface drainage from Green AASF1 empties into 

these wetlands, as well as into the unnamed streams to the north and east of the facility. Any 

surface drainage not emptied into these wetlands is captured by grated drains throughout the 

facility and the adjacent property and is discharged through an outfall east of the facility, within 

the Akron-Canton Airport facility boundary. Discharge from this outfall eventually flows into 

Schumacher Ditch, approximately 1.5 miles east of Green AASF1. Schumacher Ditch flows 

through Stark County and parts of the City of Green and discharges to the west branch of Nimisila 

Creek. 

The Akron-Canton Airport property is broken up into eight designated drainage areas, with Green 

AASF1 located in the northern-most drainage area, which is about 500 acres. This area drains 

surface water to the east/southeast and discharges through a designated outfall on the eastern 

boundary of Akron-Canton Airport, and it eventually flows into Schumacher Ditch. This outfall is 

operated and managed by the Akron-Canton Airport and holds a National Pollutant Discharge 

Elimination System permit (CHA, 2015). Four side channels are associated with this ditch; 

however, Schumacher Ditch is the main waterway that captures stormwater and surface flow from 

this entire drainage area, including the outfall associated with Green AASF1 (EDG, 1994).

2.2.4 Climate

The climate at Green AASF1 is temperate, humid subtropical, with cool to cold winters and long, 

hot summers. The average temperature is 49.9 degrees Fahrenheit (°F), with summer highs of 

80.1 °F and winter lows of 21.4 °F. The average annual precipitation is 39.62 inches (National 

Oceanic and Atmospheric Administration [NOAA], 2020).

2.2.5 Current and Future Land Use

The Green AASF1 is located on the northern portion of the Akron-Canton Regional Airport, with 

various small residential areas surrounding the facility, and several small local parks to the north 

and west. A small taxiway extends from the OHARNG apron to the intersection of Taxiway K and 

D at the Akron-Canton Airport (CHA, 2015). A helicopter pad and work area, where hover 

operations and other flight training activities are performed, are present within the facility (CHA, 

2015). Directly east of the facility boundary lies Runway 19. Within the facility boundaries are an 

AASF hangar, an armory building, helicopter parking area, and vehicle maintenance area. Within 

the National Guard complex is a Navy Operational Support Center (NOSC) that was built in 2011 

and is leased by the US Navy Reserve. This one-story facility was constructed under the Base 

Realignment and Closure process and consolidated NOSC Akron and NOSC Cleveland (CHA, 

2015). ARNG has an active lease of Green AASF until 2061, and future land use is not anticipated 

to change during that time.
FINAL Site Inspection Report

AASF1, Green Township, Summit County, Ohio

AECOM 2-4

2.2.6 Sensitive Habitat and Threatened/ Endangered Species 

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

proposed, and/ or are listed as candidate species in Summit County, Ohio (US Fish and Wildlife 

Service [USFWS], 2021). 

• Insects: Monarch butterfly, Danaus plexippus (candidate)

• Mammals: Northern long-eared bat, Myotis septentrionalis (threatened); Indiana bat, Myotis

sodalis (endangered)

• Flowering plants: Northern wild monkshood, Aconitum noveboracense (threatened)

2.3 History of PFAS Use 

Three potential PFAS release areas where aqueous film forming foam (AFFF) may have been 

used or released historically were identified at Green AASF1 during the PA (AECOM, 2020). 

Green AASF1 includes a hangar equipped with a high expansion foam (HEF) fire suppression 

system. Tri-MaxTM tanks were previously stored in the hangar before they were transferred to the 

outdoor storage area. A test of the HEF suppression system occurred in 2007 that resulted in a 

full release of the system with the bay doors closed and foam washed down the hangar drains

which connect to a municipal sewer system. Tri-MaxTM tanks that contained AFFF were stored 

outside of Green AASF1 Building 5 (cold storage area) and on the ramp area. Unintentional 

releases of the tanks may have occurred at these locations. The close proximity of releases and 

potential releases in the hangar and storage areas coupled with surface water flow to the east 

leaves the potential for migrating PFAS to impact the wetland area on the east side of the facility.
­12420 Milestone Center Drive

Germantown, MD 20876

CLIENT

REVISED

SCALE

ARNG

GIS BY

CHK BY

MS

CH

12/9/2021

12/9/2021

NOTES Site Inspection for PFAS at AASF1, OH

12/9/2021

1:63,360

PM CM 12/9/2021

C:\Users\stankevichm\OneDrive - AECOM Directory\ARNG_PFAS_GIS_60552172\MXDs\OH\Green_Armory_Figures\Green_Armory_SI_Figures\SI_Report\Fig_2-1_Green_AASF1_SI_Facility_Location.mxd

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

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

Figure 2-1

Facility Location

Legend

Facility Boundary

0 0.5 1 2

Miles

^_

AASF1

AECOM 2-5
­12420 Milestone Center Drive

Germantown, MD 20876

CLIENT

REVISED

SCALE

ARNG

GIS BY

CHK BY

MS

JW

1/31/2022

1/31/2022

NOTES Site Inspection for PFAS at AASF1, OH

1/31/2022

1:6,000

PM CM 1/31/2022

C:\Users\stankevichm\OneDrive - AECOM Directory\ARNG_PFAS_GIS_60552172\MXDs\OH\Green_Armory_Figures\Green_Armory_SI_Figures\SI_Report\Fig_2-2_Green_AASF1_SI_Facility_Topography.mxd

Base Map: USGS The National Map: National

Boundaries Dataset, 3DEP Elevation Program,

Figure 2-2

Facility Topographic Map

Legend

Facility Boundary

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Figure 2-3

Groundwater Features

Facility Boundary

Water Body

Wetland

River/Stream

Groundwater Flow Direction

Geology

Allegheny and Pottsville Groups, Undivided

Logan and Cuyahoga Formations, Undivided

Wells

!P Domestic Well

!P Commercial Well

!5 Agriculture/Irrigation Well

!5 Industrial Well

!C( Municipal/Public Water Supply Well

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AOI01-01

1214.94

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AOI02-03

1217.94

AOI03-01

1210.57

AOI01-04

1196.86

AOI01-03

1212.22

AOI02-04

NA

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Geographics, CNES/Airbus DS, USDA, USGS,

Figure 2-4

Groundwater Elevation Contours

Legend

?! DPT Soil Boring

Facility Boundary

Groundater Elevation Contours

Inferred Groundater Elevation Contours

Groundwater Flow Direction

0 200 400 800

Feet

AECOM 2-8
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Tuscarawas

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Geographics, CNES/Airbus DS, USDA, USGS,

Figure 2-5

Surface Water Features

Legend

Facility Boundary

Water Body

Wetland

River/Stream

Surface Water Flow

Direction

0 800 1,600 3,200

Feet

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3. Summary of Areas of Interest

This section presents a summary of each potential PFAS release area by AOI. Based on the PA 

findings, three potential PFAS release areas, the Storage and Ramp Area, Green AASF1 Hangar, 

and Wetland, were identified at Green AASF1 and grouped into three AOIs (AECOM, 2020). The 

potential PFAS release areas are shown on Figure 3-1. 

3.1 AOI 1 

AOI 1 consists of one potential PFAS release area. This potential release area is described below. 

3.1.1 Storage and Ramp Area

AOI 1 is the Storage and Ramp Area. During the PA, 11 TriMaxTM 30 tanks were stored outside 

the southern border of Green AASF1 Building 5 (cold storage area), on the northwestern portion 

of the aircraft parking area. Nine of the tanks were filled with concentrated 3% AFFF, while two of 

the tanks were empty. These tanks have all since been removed from the facility. Interviewees 

confirmed that one of the empty tanks was previously released during an off-facility training event

at the Akron-Canton Airport in approximately 2014 or 2015. While no spills or releases were 

reported from the nine full tanks stored outside, the storage of these tanks in a non-climatecontrolled area since at least 2017 without inspection for several years indicates a potential for 

unintended spills or releases.

The long-term storage location of the TriMaxTM tanks falls within a surface water divide; depending 

on various factors, surface water can flow to either the east or the west of the facility. Surface 

water flow to the west migrates towards off-facility wetlands and other grassy areas. Surface water 

flow to the east is towards an identified on-facility wetland, as well as towards a designated 

surface drainage system. Any potential spills or releases on or around this TriMaxTM Storage area 

have the potential to migrate to and impact these various areas.

Historical aerial photography shows the presence of mobile fire extinguishers along the paved 

ramp area from at least 2006 until 2018. Generally, safety standards require at least one mobile 

fire extinguisher for every two helicopters. During interviews, it could not be confirmed if the mobile 

extinguishers previously stored along the ramp area contained AFFF or PFAS-containing

material; however, given the historic presence of TriMaxTM tanks and other previous AFFF storage

at the facility there is the potential for these mobile fire extinguishers to have contained PFAS. 

Any potential spills or releases in this area would follow the same pattern as the long-term TriMaxTM

storage and leave the potential for PFAS exposure.

3.2 AOI 2 

AOI 2 consists of one potential PFAS release area. This potential release area is described below.

3.2.1 Green AASF1 Hangar

AOI 2 is the Green AASF1 Hangar. The Green AASF1 Hangar was constructed between 1987 

and 1988 and includes a main hangar that is used for aviation maintenance and aircraft storage. 

Original construction of the Green AASF Hangar did not include a fire suppression system. The 

Green AASF1 Hangar was retrofitted in 2006 to include a HEF fire suppression system. This fire 

suppression system included a 400-gallon tank that contained concentrated Buckeye HEF 2.2%. 

In 2007, a test of the system occurred that resulted in a full release of the system. According to 

interviewees, the bay doors were closed, and all foam from the test was washed down the drains 

within the Green AASF1 Hangar. The drains within the Green AASF1 Hangar are connected to 
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an underground oil water separator that then routes any residual material to the local municipal 

wastewater system. 

Five TriMaxTM tanks that were located within the TriMaxTM storage area were previously stored 

inside the Green AASF1 Building area (since approximately 2000 or 2001) and then transferred 

to outside storage sometime within the last several years. The long-term and undocumented 

storage of these tanks within Green AASF1 leave the potential for unintended spills or releases.

During the site visit, interviewees noted that 26 5-gallon containers of AFFF concentrate were 

removed from the Green AASF1 Hangar and were properly transported and disposed of off-facility

in approximately April 2018. According to base personnel, all 26 5-gallon buckets of AFFF were 

unopened and unused during the entire duration of storage at the facility. It is estimated that the 

containers were located within the facility for approximately 10 years prior to disposal; however, 

it is unknown where the buckets originated from. Interviewees also had no knowledge of the 

procurement of the AFFF buckets, and there was no knowledge of spills or releases during their 

time of storage at the facility. 

3.3 AOI 3 

AOI 3 consists of one potential PFAS release area. This potential release area is described below. 

3.3.1 Wetland

AOI 3 is a small wetland on the southeast edge of the facility property that extends on- and offfacility. Several wetlands exist directly around the facility. Surface drainage from Green AASF1 

empties into these various wetlands, including the wetland partially located within the facility 

property, as well as into the unnamed streams to the north and east of the facility. Any surface 

runoff not directed into these wetlands is captured by grated drains throughout the facility and the 

adjacent property. These drain discharge through an outfall east of the facility, within the AkronCanton Airport facility boundary.

While there have been no known or suspected releases directly into the on-facility wetland, the

historical storage of AFFF and potential releases at AOI 1 and AOI 2 coupled with the close 

proximity of the wetland and general surface water flow direction to the east leave the potential 

for migrating PFAS to impact this wetland. This wetland can receive and store potentially impacted 

stormwater and surface water runoff from around the facility.
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West Branch

Nimishillen

Creek Watershed

Nimisila

Reservoir-Nimisila

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AOI 1 AOI 3

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Base Map: Source: Esri, Maxar, GeoEye, Earthstar

Geographics, CNES/Airbus DS, USDA, USGS,

Figure 3-1

Areas of Interest

Legend

Area of Interest

Potential PFAS Release

Facility Boundary

Water Body

Wetland

River/Stream

Surface Water Flow Direction

Groundwater Flow Direction

!P Domestic Well

A! Monitoring Well

A! Other Well

0 500 1,000 2,000

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4. Project Data Quality Objectives

Project Data Quality Objectives (DQOs) are qualitative and quantitative statements that specify 

the quality of data and define the level of certainty required to support project decision-making

process. The specific DQOs established for this facility are described below. These DQOs were 

developed in accordance with the USEPA’s seven-step iterative process (USEPA, 2006). 

4.1 Problem Statement

The following problem statement was developed during project planning:

The presence of PFAS, which may pose a risk to human health or the environment, in 

environmental media at the facility is currently unknown. PFAS are classified as emerging 

environmental contaminants that are garnering increasing regulatory interest due to their potential 

risks to human health and the environment. The regulatory framework for managing PFAS at both 

the federal and state level continues to evolve. 

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 Office of the Secretary of 

Defense (OSD) dated 15 September 2021 (Assistant Secretary of Defense, 2021). The ARNG 

program under which this SI was performed follows this DoD policy. Should the maximum site 

concentration for sampled media exceed the SLs established in the OSD memorandum, the AOI

will proceed to the next phase under CERCLA. The SLs established in the OSD memorandum 

apply to three compounds: PFOS, PFOA, and PFBS. 

The SLs are presented in Section 6.1 of this Report.

The following quotes from the DA policy documents form the basis for this project (DA, 2016; DA, 

2018): 

• “The Army will research and identify locations where PFOS- and/or PFOA-containing

products, such as AFFF, are known or suspected to have been used. Installations shall

coordinate with installation/facility fire response or training offices to identify AFFF use or

storage locations. The Army will consider FTAs, AFFF storage locations, hangars/buildings

with AFFF suppression systems, fire equipment maintenance areas, and areas where

emergency response operations required AFFF use as possible source areas. In addition,

metal plating operations, which used certain PFOS-containing mist suppressants, shall be

considered possible source areas.”.

• “Based on a review of site records...determine whether a CERCLA PA is appropriate for

identifying PFOS/PFOA release sites. If the PA determines a PFOS/PFOA release may

have occurred, a CERCLA SI shall be conducted to determine presence/absence of

contamination.”.

• “Identify sites where perfluorinated compounds are known or suspected to have been

released, with the priority being those sites within 20 miles of the public systems that tested

above USEPA Health Advisory (HA) levels.” (USEPA, 2016a; USEPA, 2016b).

4.2 Goals of the Study

The following goals were established for this SI:

1. Determine the presence or absence of PFOA, PFOS, and PFBS at or above SLs.
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2. Develop information to potentially eliminate a release from further consideration because

it is determined that it poses no significant threat to human health or the environment.

3. Determine the potential need for a Time Critical Removal Action (TCRA) (applies to

drinking water only). The primary actions that will be considered include provision of

alternative water supplies or wellhead treatment.

4. Collect data to better characterize the release areas for more effective and rapid initiation

of a RI (if determined necessary).

5. If PFOA, PFOS, and PFBS are determined to be present, aim to evaluate whether the

concentrations can be attributed to on-facility or off-facility sources that were identified

within 4 miles of the installation as part of the PA (e.g., fire stations, major manufacturers,

other DoD facilities).

6. Determine whether a potentially complete pathway exists between the source and

potential receptors and whether ARNG is the likely source of the contamination.

4.3 Information Inputs

Primary information inputs included:

• The PA for Green AASF1 (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)-Quality Assurance Project Plan (QAPP)

Addendum (AECOM, 2021a); and

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

parameters measured at the time of sampling.

4.4 Study Boundaries

The scope of the SI was bounded by the property limits of the facility (Figure 2-1). Off-facility sampling 

was not included in the scope of this SI. If future off-facility sampling is required, the proper 

stakeholders will be notified, and necessary rights of entry will be obtained by ARNG with property 

owner(s).

4.5 Analytical Approach

Samples were analyzed by Pace Analytical Gulf Coast, accredited under the 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 and decision rules as defined in the SI QAPP Addendum (AECOM, 

2021a). These rules governed response actions based on the results of the SI sampling effort.

The decision rules described in the Worksheet #11 of the SI QAPP Addendum identify actions 

based on the following:

Groundwater:

• Is there a human receptor within 4 miles of the facility?

• What is the concentration of PFOA, PFOS, and PFBS at the potential release areas?
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• What is the concentration of PFOA, PFOS, and PFBS at the facility boundary upgradient

and downgradient of the potential release areas?

• What does the conceptual site model (CSM) suggest in terms of source, pathway and

receptor?

Soil:

• What is the concentration of PFOA, PFOS, and PFBS in shallow surface soil (0 to 2 feet

bgs)?

• What is the concentration of PFOA, PFOS, and PFBS in deep soil (i.e., vadose zone and

capillary fringe)?

• What does the CSM suggest in terms of source, pathway, and receptor?

Soil and groundwater samples were collected from each of the potential release areas. 

Groundwater was encountered at approximately 2.27 to 18.31 feet bgs. 

4.6 Data Usability Assessment 

The Data Usability Assessment (DUA) is an evaluation at the conclusion of data collection 

activities that uses the results of both data verification and validation in the context of the overall 

project decisions or objectives. Using both quantitative and qualitative methods, the assessment 

determines whether project execution and the resulting data have met installation-specific DQOs. 

Both sampling and analytical activities are considered to assess whether the collected data are 

of the right type, quality, and quantity to support the decision-making (DoD, 2019a; DoD, 2019b; 

USEPA, 2017b). 

Data Quality Indicators (DQIs) (Precision, Accuracy, Representativeness, Comparability, 

Completeness and Sensitivity) are important components in assessing data usability. These DQIs 

were evaluated in the subsequent sections and demonstrate that the data presented in this SI 

report are of high quality. Although the SI data are considered reliable, some degree of uncertainty 

can be associated with the data collected. Specific factors that may contribute to the uncertainty 

of the data evaluation are described below. The Data Validation Report (DVR) (Appendix A) 

presents explanations for all qualified data in greater detail.

4.6.1 Precision

Precision is the degree of agreement among repeated measurements of the same characteristic 

on the same sample or on separate samples collected as close as possible in time and place. 

Field sampling precision is measured with the field duplicate relative percent differences (RPD); 

laboratory precision is measured with calibration verification, internal standard recoveries, 

laboratory control spike (LCS) and matrix spike (MS) duplicate RPD.

Injection internal standards (IIS) were added by the laboratory after sample extraction and prior 

to analysis as a legacy requirement of DoD QSM 5.1 to measure relative responses of target 

analytes. Even though not required under DoD QSM 5.3, the IIS are still added to the sample 

after extraction as an additional quality control (QC) measure. The IIS percent recoveries were 

within the established precision limits presented in the QAPP Addendum (AECOM, 2021a). 

LCS/LCS duplicate (LCS/LCSD) pairs were prepared by addition of known concentrations of each 

analyte in a matrix-free media known to be free of target analytes. LCS/LCSD pairs were analyzed 

for every analytical batch to demonstrate the ability of the laboratory to detect similar 

concentrations of a known quantity in matrix-free media. The LCS/LCSDs performed during the 
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laboratory analyses were within the project established precision limits presented in the QAPP 

Addendum (AECOM, 2021a). 

MS/MS duplicate (MS/MSD) samples were prepared, analyzed, and reported for all preparation 

batches. MS/MSD samples demonstrated that the analytical system was in control for the matrix 

being tested. MS/MSD samples were submitted to the laboratory for analysis at a rate of 5%. The 

MS/MSD samples were within the project established precision limits presented in the QAPP 

Addendum (AECOM, 2021a), with limited exceptions. The MS/MSD performed on parent sample 

GRN-AOI02-01-SB-2-4 displayed a relative percent difference (RPD) greater than the QC limit for 

perfluorohexanoic acid (PFHxA). The field sample result associated with MS/MSD RPD 

exceedance was qualified as estimate and should be considered usable as qualified.

Field duplicate samples were collected at a rate of 10% to assess the overall sampling and 

measurement precision for this sampling effort. The field duplicate samples were analyzed for 

PFAS and general chemistry parameters. The field duplicate samples were within the project 

established precision limits presented in the QAPP Addendum (AECOM, 2021a) with limited 

exceptions. Three separate field duplicate pairs displayed positive results in one sample and nondetect results in the other sample. The field duplicate pair results were qualified as estimate and 

the qualified field duplicate pair results should be considered usable as estimated values. 

4.6.2 Accuracy

Accuracy is a measure of confidence in a measurement. The smaller the difference between the 

measurement of a parameter and its "true" or expected value, the more accurate the 

measurement. The more precise or reproducible the result, the more reliable or accurate the 

result. Accuracy is measured through percent recoveries in the LCS/LCSD, MS/MSD, and 

surrogates.

LCS/LCSD samples were prepared by addition of known concentrations of each analyte in a 

matrix free media known to be free of target analytes. LCS/LCSD samples were analyzed for 

every analytical batch and demonstrated that the analytical system was in control during sample 

preparation and analysis. The LCS/LCSDs performed during the laboratory analyses were within 

the project established accuracy limits presented in the QAPP Addendum (AECOM, 2021a). 

Extraction internal standards (EIS) were added by the laboratory during sample extraction to 

measure relative responses of target analytes and used to correct for bias associated with matrix 

interferences and sample preparation efficiencies, injection volume variances, mass spectrometry 

ionization efficiencies, and other associated preparation and analytical anomalies. The EIS area 

counts were within the project established precision limits presented in the QAPP Addendum 

(AECOM, 2021a), with several exceptions. Five investigative field samples and eight QC samples 

displayed EIS area counts less than the lower QC limit for several target analytes. Field sample 

results are not qualified based on QC sample EIS area count anomalies and should be considered 

usable as reported. The positive field sample results associated with low EIS area counts were 

qualified as estimate with a high bias, while non-detect results were qualified as estimate and 

should be considered usable as qualified. 

MS/MSD samples were prepared, analyzed, and reported at a rate of 5%. MS/MSD samples 

demonstrated that the analytical system was in control for the matrix being tested. The MS/MSDs 

performed during that laboratory analyses were within the project established accuracy limits 

presented in the QAPP Addendum (AECOM, 2021a), with limited exceptions. Two parent samples 

displayed MS/MSD percent recoveries outside the QC limits. The positive parent sample result 

associated with low MS/MSD percent recovery was qualified as estimate with a low bias. The 

positive parent sample result associated with the high MS/MSD percent recovery was qualified 

as estimate with a high bias. The associated field sample results should be considered usable as 

qualified. 
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Calibration verifications (CCV) were performed routinely to ensure that instrument responses for 

all calibrated analytes were within established QC criteria. The calibration verifications performed 

during the laboratory analyses were within the project established accuracy limits presented in 

the QAPP Addendum (AECOM, 2021a), with one exception. One CCV displayed percent 

recoveries less than the QC limit for perfluorohexanesulfonic acid (PFHxS) and PFOS. These 

were not target analytes in the associated batch, so there was no impact on data quality.

4.6.3 Representativeness

Representativeness qualitatively expresses the degree to which data accurately reflect site 

conditions. Factors that affect the representativeness of analytical data include appropriate 

sample population definitions, proper sample collection and preservation techniques, analytical 

holding times, use of standard analytical methods, and determination of matrix or analyte 

interferences. 

Relating to the use of standard analytical methods, the laboratory followed the method as 

established in PFAS by liquid chromatography with tandem mass spectrometry (LC/MS/MS) 

Compliant with Quality Systems Manual (QSM) Table B-15, including the specific preparation 

requirements (i.e. ENVI-Carb or equivalent used), mass calibration, spectra, all the ion transitions 

identified in Table B-15 were monitored, standards that contained both branched and linear 

isomers when available were used, and isotopically labeled standards were used for quantitation.

Field QC samples were collected to assess the representativeness of the data collected. Field 

duplicates were collected at a rate of 10% for all field samples, while MS/MSD samples were 

collected at a rate of 5%. All preservation techniques were followed by the field staff, and all 

technical and analytical holding times were met by the laboratory, with limited exceptions. The 

field samples submitted in SDG 221061935 were received by the laboratory at 6.2 degrees 

Celsius (°C). The samples were still considered preserved, the associated field sample results

were qualified as estimate and should be considered usable as qualified. The laboratory used 

approved standard methods in accordance with the QAPP Addendum (AECOM, 2021a) for all 

analyses.

Instrument blanks and method blanks were prepared by the laboratory in each batch as a negative 

control. Six instrument blanks and one method blank displayed concentrations for multiple 

analytes greater than the detection limit (DL). The positive field sample results associated with 

the blank detections that displayed concentrations less than five times the blank detections were 

qualified as likely false positives and should be treated as non-detect. The remaining field sample 

results associated with the blank detections were all greater than five times the blank 

concentration or were non-detect, and these associated field sample results should be considered 

usable as reported. 

Field blanks and equipment blanks were also collected for groundwater and soil samples. All 

equipment blanks and field blanks were non-detect for all target analytes. 

A sample of the water used for decontamination of the drill rig was collected in advance of the 

field effort. The decontamination samples, GRN-PW-01 and GRN-PW-01-FD, displayed 

concentrations for several target analytes greater than the DLs. The remaining field sample 

results associated with the blank detections were all greater than five times the blank 

concentration or were non-detect. The associated field sample results should be considered 

usable as reported.

Field samples were extracted and analyzed within the appropriate holding time in order to 

qualitatively express the degree to which data accurately reflect site conditions, with limited 

exceptions. Eight field samples were re-extracted and reanalyzed outside technical holding time 

due to QC failures. The associated field sample results were qualified as estimate and should be 
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considered usable as qualified. The holding time for pH analysis is “immediate”, and all field 

samples analyzed for pH were qualified as estimate and should be considered usable as qualified.

Overall, the data are usable for evaluating the presence or absence of PFAS at the facility. 

Sufficient usable data were obtained to meet the objectives of the SI.

4.6.4 Comparability

Comparability is the extent to which data from one study can be compared directly to either past 

data from the current project or data from another study. Using standardized sampling and 

analytical methods, units of reporting, and site selection procedures help ensure comparability. 

Standard field sampling and typical laboratory protocols were used during the SI and are 

considered comparable to ongoing investigations.

4.6.5 Completeness

Completeness is a measure of the amount of valid data obtained from a measurement system 

compared to the amount of data expected under normal conditions. The laboratory provided data 

that met system QC acceptance criteria for all samples tested. Project completeness was 

determined by evaluating the planned versus actual quantities of data. Percent completeness per 

parameter is as follows and reflects the exclusion of “X” flagged data, if applicable:

• PFAS in groundwater by DoD QSM B-15 at 100%

• PFAS in soil by DoD QSM B-15 at 100%

• pH in soil by USEPA Method 9045D at 100%

• Total organic carbon (TOC) by USEPA Method 9060 at 100%

One groundwater sample was not collected due to refusal. This is described further in Section 

5.2. 

4.6.6 Sensitivity

Sensitivity is the capability of a test method or instrument to discriminate between measurement 

responses representing different levels (e.g., concentrations) of a variable of interest. Examples 

of QC measures for determining sensitivity include laboratory fortified blanks, an MDL study, and 

calibration standards at the limit of quantitation (LOQ). In order to meet the needs of the data 

users, project data must meet the measurement performance criteria for sensitivity and project 

LOQs specified in the QAPP Addendum (AECOM, 2021a). The laboratory provided the requested 

MDL studies and provided applicable calibration standards at the LOQ. In order to achieve the 

DQOs for sensitivity outlined in the QAPP Addendum (AECOM, 2021a), the laboratory reported 

all field sample results at the lowest possible dilution. Additionally, any analytes detected below 

the LOQ and above the DL were reported and qualified “J” as estimated values by the laboratory.
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5. Site Inspection Activities 

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

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

in accordance with the following approved documents: 

 Final Preliminary Assessment Report, AASF1, Green Township, Summit County, Ohio 

dated June 2020 (AECOM, 2020); 

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

dated March 2018 (AECOM, 2018a); 

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

AASF1, Green Township, Summit County, Ohio dated June 2021 (AECOM, 2021a); 

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

 Final Site Safety and Health Plan, AASF1, Green Township, Summit County, Ohio dated 

June 2021 (AECOM, 2021b). 

The SI field activities were conducted from 16 to 18 June 2021 and consisted of utility clearance, 

direct push boring, soil sample collection, temporary monitoring well installation, grab groundwater 

sample collection, and land surveying. Field activities were conducted in accordance with the SI 

QAPP Addendum (AECOM, 2021a). 

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

LC/MS/MS compliant with QSM 5.3 Table B-15 to fulfill the project DQOs: 

 Twenty-five (25) soil samples from nine boring locations; 

 Eight grab groundwater samples from eight temporary well locations; 

 Twelve (12) quality assurance (QA) 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, land survey data are provided in 

Appendix B3, investigation-derived waste (IDW) logs are provided in Appendix B4, and 

Nonconformance and Corrective Action Reports are included 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 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 collection plan. The process encourages 

stakeholder involvement in the SI, beginning with defining overall project objectives, including 

quantitative and qualitative DQOs, and formulating a sampling approach to address the AOIs 

identified in the PA. 
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AASF1, Green Township, Summit County, Ohio

AECOM 5-2

A combined TPP Meeting 1 and 2 was held on 23 November 2020, 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, OHARNG, USACE, Ohio Environmental Protection

Agency (Ohio EPA), and representatives familiar with the facility, the regulations, and the 

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

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

combined TPP Meeting 1 and 2 was memorialized in the SI QAPP Addendum (AECOM, 2021a).

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 Ohio811 

“Call Before You Dig” utility clearance provider to notify them of intrusive work on 7 June 2021. 

However, because the AASF is a private facility, the participating “Call Before You Dig” locators 

did not clear utilities at the entire facility. Therefore, AECOM contracted Ground Penetrating Radar 

Services, LLC (GPRS), a private utility location service, to complete the on-facility utility 

clearance. GPRS performed utility clearance of the proposed boring locations on 11 June 2021 

with input from the AECOM field team and Green AASF1 facility staff. General locating services 

and ground-penetrating radar were used to complete the clearance. Additionally, the first 5 feet of 

each boring were pre-cleared using a hand auger to verify utility clearance in shallow subsurface

soils where utilities would typically be encountered.

5.1.3 Source Water and PFAS Sampling Equipment Acceptability

The potable water source used for decontamination of drilling equipment was confirmed to be 

acceptable for use in a PFAS investigation prior to the start of field activities. A sample from the

potable water source at Green AASF1 was collected on 5 January 2021, prior to mobilization, and 

analyzed for PFAS by LC/MS/MS compliant with QSM 5.3 Table B-15. The results of the 

decontamination water sample are provided in Appendix F. A discussion of the results is 

presented in Section 4.6.3.

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

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

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

QAPP Addendum (AECOM, 2021a). Prior to the start of field work each day, a PFAS 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 Soil Borings and Soil Sampling

Soil samples were collected via direct push technology (DPT), in accordance with the SI QAPP 

Addendum (AECOM, 2021a). A GeoProbe® 7822DT dual-tube sampling system was used to 

collect continuous soil cores to the target depth. A hand auger was used to collect soil from the 

top five feet of the boring, in accordance with AECOM utility clearance procedures. The soil boring 

locations are shown on Figure 5-1 and depths are provided Table 5-1.

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

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

approximately 2 feet above the groundwater table, and one subsurface soil sample at the midpoint between the surface and the groundwater table. 
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AASF1, Green Township, Summit County, Ohio

AECOM 5-3

The soil cores were continuously logged for lithological descriptions by a field geologist using the 

Unified Soil Classification System (USCS). A photoionization detector (PID) was used to screen 

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

and measurements were recorded on sampling forms (Appendix B2) and in a non-treated 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. 

Soil borings completed during the SI found well-graded sand, clay, and clayey sand as the 

dominant lithology of the soils below Green AASF1. The borings were completed at depths 

between 10 and 25 ft bgs. Below the first layers of sand, the lithology was predominantly clays, 

including fat clay, lean clay, and clayey sand. The clay layers extended the length of the boring. 

Some borings included sections of gravel in the deeper sandy layers. These observations are 

consistent with the understood geologic environment of the area.

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 for PFAS (LC/MS/MS compliant with QSM 5.3 Table B-15), TOC 

(USEPA Method 9060A) and pH (USEPA Method 9045D) in accordance with the SI QAPP 

Addendum (AECOM, 2021a). 

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. In instances when non-dedicated sampling 

equipment was used, such as a hand auger for the shallow soil samples, equipment Rinsate 

blanks (ERBs) 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 °C during shipment.

DPT borings were converted to temporary wells, which were subsequently abandoned in 

accordance with the SI QAPP Addendum (AECOM, 2021a) using wetted bentonite chips at 

completion of sampling activities. Borings were installed in grass areas to avoid disturbing 

concrete or asphalt surfaces.

5.3 Temporary Well Installation and Groundwater Grab Sampling

Temporary wells were installed using a GeoProbe® 7822DT dual-tube sampling system. Once 

the borehole was advanced to the desired depth, wherever conditions allowed, a temporary well 

was constructed of a 5-foot section of 1-inch Schedule 40 poly-vinyl chloride (PVC) screen with 

sufficient casing to reach ground surface. New PVC pipe and screen were used to avoid cross 

contamination between locations. The screen intervals for the temporary wells are provided in 

Table 5-2. 

The temporary wells were allowed to recharge after installation before collection of groundwater 

samples. After the recharge period, groundwater samples were collected using a peristaltic pump 

with PFAS-free HDPE tubing. Each sample was collected into laboratory-supplied PFAS-free 

HDPE bottles and labeled using a PFAS-free marker or pen. The temporary wells were purged at 

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

parameters (e.g., temperature, specific conductance, pH, dissolved oxygen [DO], and oxidationreduction potential [ORP]) were measured using a water quality meter and recorded on the field 

sampling form (Appendix B2) after each grab sample was collected. 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. 
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AECOM 5-4

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 for PFAS by LC/MS/MS compliant with 

QSM 5.3 Table B-15 in accordance with the SI QAPP Addendum (AECOM, 2021a). 

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. One field reagent blank (FRB) was collected in 

accordance with the Programmatic UFP-QAPP (PQAPP) (AECOM, 2018a). A temperature blank 

was placed in each cooler to ensure that samples were preserved at or below 6°C during 

shipment.

Temporary wells were abandoned in accordance with the SI QAPP Addendum (AECOM, 2021a) 

by removing the PVC and backfilling the hole with wetted bentonite chips. Temporary wells were 

installed in grass areas to avoid disturbing concrete or asphalt. 

5.4 Synoptic Water Level Measurements

A synoptic groundwater gauging event was performed on 16 to 18 June 2021. Groundwater

elevation measurements were collected from the 8 new temporary monitoring wells. Water level 

measurements were taken from the northern side of the well casing. A groundwater flow contour 

map is provided in Figure 2-4. Groundwater elevation data are provided in Table 5-2. 

5.5 Surveying 

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

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

data from the newly installed wells on the facility were collected on 18 June 2021 in the applicable 

Universal Transverse Mercator zone projection with World Geodetic System 84 datum (horizontal) 

and North American Vertical Datum 1988 (vertical). The surveyed well data are provided in 

Appendix B3. 

5.6 Investigation-Derived Waste

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

generated during the SI is considered non-hazardous waste and was managed in accordance 

with the SI QAPP Addendum (AECOM, 2021a) and with the DA Guidance for Addressing Releases 

of PFAS, Q18 (DA, 2018). 

Soil IDW (i.e., soil cuttings) generated during the SI activities was containerized in one properly 

labeled 55-gallon drum. The soil IDW was not sampled and assumes the PFAS characteristics of 

the associated soil samples collected from that source location. The IDW is currently stored onfacility at a location designated by the OHARNG Environmental Office. ARNG will manage 

disposal of the solid IDW and ensure proper disposal in accordance with the Army Guidance for 

Addressing Releases of PFAS, Q18 (DA, 2018). 

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

decontamination fluids) was containerized in one properly-labeled 55-gallon drum (see SOP 3-

05). The liquid IDW was not sampled and assumes the PFAS characteristics of the associated 

groundwater samples collected from that source location. The containerized IDW is currently 

stored on-facility at a location designated by OHARNG. Liquid IDW drums were only filled 75% 

full to account for freeze/thaw cycles. ARNG will manage and dispose of the liquid IDW under a 

separate contract in accordance with SOP No. 042A for Treating Liquid Investigation-Derived 

Material (purge water, drilling water, and decontamination fluids) (EA Engineering, Science, and 
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AASF1, Green Township, Summit County, Ohio 

AECOM 5-5 

Technology, Inc., 2021). ARNG will coordinate proper disposal in accordance with the Army 

Guidance for Addressing Releases of PFAS, Q18 (DA, 2018). The IDW logs describing the 

storage location and relative volume of soil and liquid IDW are documented in Appendix B4. 

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 for a subset of 18 PFAS 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. The 18 PFAS analyzed as part of the ARNG SI program include the following: 

 6:2 fluorotelomer sulfonic acid (6:2 FTS) 

 8:2 fluorotelomer sulfonic acid (8:2 FTS) 

 N-ethyl perfluorooctanesulfonamidoacetic 

acid (NEtFOSAA) 

 N-methyl 

perfluorooctanesulfonamidoacetic acid 

(NMeFOSAA) 

 Perfluorobutyrate (PFBA) 

 Perfluorobutanesulfonic acid (PFBS) 

 Perfluorodecanoic acid (PFDA) 

 Perfluorododecanoic acid (PFDoA) 

 Perfluoroheptanoic acid (PFHpA) 

 Perfluorohexanoic acid (PFHxA) 

 Perfluorohexanesulfonic acid (PFHxS) 

 Perfluorononanoic acid (PFNA) 

 Perfluorooctanoic acid (PFOA) 

 Perfluorooctanesulfonic acid (PFOS) 

 Perfluoropentanoic acid (PFPeA) 

 Perfluorotetradecanoic acid (PFTeDA) 

 Perfluorotridecanoic acid (PFTrDA) 

 Perfluoroundecanoic acid (PFUdA) 

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

9045D. 

5.8 Deviations from SI QAPP Addendum 

Four deviations from the SI QAPP Addendum were identified following conclusion of the field 

sampling activities. The deviations are noted below. Documentation of the deviations, such as in 

a Nonconformance and Corrective Action Report, are also included in Appendix B5. 

 During SI fieldwork, the coordinates of the proposed location for AOI01-03 were 

discovered to be outside the facility’s fence line. AOI01-03 was relocated inside the facility 

fence line. 

 During SI fieldwork, temporary monitoring well AOI02-04 did not contain any water; 

therefore, a groundwater sample was not collected from this location. 

 Upon visual review of the boring location AOI02-03, the OHARNG discovered that the 

temporary well installed during the SI had not been properly abandoned. As a result, the 

field team re-mobilized to the facility on 9 July 2021 to complete the abandonment of this 

temporary well using wetted bentonite chips. This action was documented in a 

Nonconformance and Corrective Action Report provided in Appendix B5. 

 Upon review of field documentation, it was discovered that one surface soil sample, 

AOI01-01-SB-2-4, was not collected during the SI field effort. As a result, the field team 
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AASF1, Green Township, Summit County, Ohio 

AECOM 5-6 

re-mobilized to the facility on 24 August 2021 to collect this surface soil sample and 

shipped it to the laboratory for analysis. This action was documented in a Nonconformance 

and Corrective Action Report provided in Appendix B5.

 Upon review of field documentation, it was discovered that minimum temporary well 

purging and/or groundwater sample turbidity requirements were not met during the SI field 

effort. As a result, the laboratory performed extra processes to enable adequate analysis 

of samples collected with high turbidity. This action was documented in a Nonconformance 

and Corrective Action Report provided in Appendix B5.
Table 5-1

Site Inspection Samples by Medium

Site Inspection Report, Green AASF1, Ohio

Sample Identification

Sample

Collection 

Date, Time

Sample Depth 

(feet bgs)

PFAS by LC/MS/MS compliant with QSM 5.3 Table B-15TOC(USEPA Method 9060A)pH (USEPA Method 9045D)Grain Size (ASTM D-422)

Comments

GRN-AOI01-01-SB-0-2 6/17/2021 14:20 0-2

GRN-AOI01-01-SB-2-4 6/17/2021 14:35 2-4 x

GRN-AOI01-01-SB-2-4 MS 6/17/2021 14:35 2-4 x MS/MSD

GRN-AOI01-01-SB-2-4 MSD 6/17/2021 14:35 2-4 x MS/MSD

GRN-AOI01-02-SB-0-2 6/17/2021 13:20 0-2 x x x

GRN-AOI01-02-SB-4-6 6/17/2021 13:30 4-6 x

GRN-AOI01-02-SB-4-6-DUP 6/17/2021 13:30 4-6 x FD

GRN-AOI01-02-SB-6-8 6/17/2021 13:35 6-8 x

GRN-AOI01-03-SB-0-2 6/17/2021 11:00 0-2 xxxx

GRN-AOI01-03-SB-0-2-DUP 6/17/2021 11:00 0-2 x x FD

GRN-AOI01-03-SB-2-4 6/17/2021 11:05 2-4 x

GRN-AOI01-03-SB-2-4-DUP 6/17/2021 11:05 2-4 x FD

GRN-AOI01-04-SB-0-2 6/17/2021 8:50 0-2 x

GRN-AOI01-04-SB-6-8 6/17/2021 9:00 6-8 x

GRN-AOI01-04-SB-13-15 6/17/2021 9:05 13-15 x

GRN-AOI02-01-SB-0-2 6/16/2021 15:00 0-2 x

GRN-AOI02-01-SB-7-9 6/16/2021 15:25 7-9 x

GRN-AOI02-01-SB-13-15 6/16/2021 15:30 13-15 x

GRN-AOI02-02-SB-0-2 6/17/2021 15:40 0-2 x

GRN-AOI02-02-SB-4-6 6/17/2021 15:50 4-6 x x x

GRN-AOI02-02-SB-4-6-DUP 6/17/2021 15:50 4-6 x FD

GRN-AOI02-02-SB-8-10 6/17/2021 15:55 8-10 x

GRN-AOI02-03-SB-0-2 6/16/2021 16:30 0-2 x

GRN-AOI02-03-SB-2-4 6/16/2021 16:35 2-4 x

GRN-AOI02-03-SB-4-6 6/16/2021 16:40 4-6 x

GRN-AOI02-04-SB-0-2 6/18/2021 8:30 0-2 x

GRN-AOI02-04-SB-6-8 6/18/2021 8:35 6-8 x x x

GRN-AOI02-04-SB-13-15 6/18/2021 8:40 13-15 x

GRN-AOI03-01-SB-0-2 6/17/2021 10:05 0-2 x

GRN-AOI03-01-SB-2-4 6/17/2021 10:10 2-4 x

GRN-AOI03-01-SB-4-6 6/17/2021 10:15 4-6 x

GRN-AOI01-01-GW 6/18/2021 8:15 NA x

GRN-AOI01-02-GW 6/17/2021 15:00 NA x

GRN-AOI01-03-GW 6/17/2021 13:15 NA x

GRN-AOI01-04-GW 6/18/2021 9:00 NA x

GRN-AOI02-01-GW 6/17/2021 9:40 NA x

GRN-AOI02-01-GW-DUP 6/17/2021 9:40 NA x FD

GRN-AOI02-02-GW 6/18/2021 10:00 NA x

GRN-AOI02-03-GW 6/17/2021 10:45 NA x

GRN-AOI02-03-GW-MS 6/17/2021 10:50 NA x MS/MSD

GRN-AOI02-03-GW-MSD 6/17/2021 10:55 NA x MS/MSD

GRN-AOI03-01-GW 6/17/2021 12:20 NA x

Soil Samples

Groundwater Samples

AECOM 5-7
Table 5-1

Site Inspection Samples by Medium

Site Inspection Report, Green AASF1, Ohio

Sample Identification

Sample

Collection 

Date, Time

Sample Depth 

(feet bgs)

PFAS by LC/MS/MS compliant with QSM 5.3 Table B-15TOC(USEPA Method 9060A)pH (USEPA Method 9045D)Grain Size (ASTM D-422)

Comments

GRN-FRB-01 6/17/2021 11:00 NA x

GRN-ERB-01 6/17/2021 13:30 NA x

GRN-ERB-02 6/18/2021 10:00 NA x

Notes:

ASTM = American Society for Testing and Materials

bgs = below ground surface

ERB = equipment rinsate blank

FD = field duplicate

FRB = field reagent blank

LC/MS/MS = Liquid Chromatography Mass Spectrometry

MS/MSD = matrix spike/ matrix spike duplicate

PFAS = per- and polyfluoroalkyl substances

QSM = Quality Systems Manual

RAE = Rickenbacker Army Enclave

TOC = total organic carbon

USEPA = United States Environmental Protection Agency

Quality Control Samples

AECOM 5-8
Table 5-2

Soil Boring Depths, Temporary Well Screen Intervals, and Groundwater Elevations

Site Inspection Report, Green AASF1, Ohio

Area of 

Interest

Boring 

Location

Soil Boring 

Depth 

(feet bgs)

Temporary Well 

Screen Interval 

(feet bgs)

Top of Casing 

Elevation 

(feet NAVD88)

Ground Surface 

Elevation 

(feet NAVD88)

Depth to 

Water

(feet btoc)

Dep

W

(fee

AOI 1 AOI01-01 10 5 - 10 1217.738 1217.210 2.8 2

AOI 1 AOI01-02 15 5 - 15 1216.3337 1215.980 2.92 2

AOI 1 AOI01-03 15 5 - 15 1216.444 1216.022 4.22 3

AOI 1 AOI01-04 20 10 - 20 1215.613 1215.174 18.75 18

AOI 2 AOI02-01 25 15 - 25 1216.134 1215.879 13.88 13

AOI 2 AOI02-02 15 5 - 15 1220.082 1219.927 5.05 4

AOI 2 AOI02-03 10 5 - 10 1223.294 1222.983 5.35 5AOI 2 AOI02-04 15 5 - 15 1219.969 1219.517 NA NAOI 3 AOI03-01 15 5 - 15 1215.940 1215.275 5.37 4

Notes:

1 Temporary well screen set above total depth to capture groundwater interface

bgs = below ground surfacebtoc = below top of casingNA = not applicableNAVD88 = North American Vertical Datum 1988

AECOM 
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AECOM 5-10

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AOI 2

AOI 1

AOI 3

AOI01-01

AOI01-02

AOI02-01 AOI02-02

AOI02-03

AOI03-01

AOI01-04

AOI01-03

AOI02-04

­12420 Milestone Center Drive

Germantown, MD 20876

CLIENT

REVISED

SCALE

ARNG

GIS BY

CHK BY

MS

JW

3/9/2022

3/9/2022

NOTES Site Inspection for PFAS at AASF1, OH

3/9/2022

1:4,800

PM CM 3/9/2022

C:\Users\stankevichm\OneDrive - AECOM Directory\ARNG_PFAS_GIS_60552172\MXDs\OH\Green_Armory_Figures\Green_Armory_SI_Figures\SI_Report\Fig_5-1_Green_AASF1_SI_Final_Sample_Locations.mxd

Base Map: Source: Esri, Maxar, GeoEye, Earthstar

Geographics, CNES/Airbus DS, USDA, USGS,

Figure 5-1

Site Inspection Sample Locations

Legend

?! DPT Soil Boring

Area of Interest

Facility Boundary

Surface Water Flow Direction

Groundwater Flow Direction

0 200 400 800

Feet

AECOM 5-11
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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 6-4 present PFAS results for samples with 

detections in soil, or groundwater; only constituents detected in one or more samples are 

included. Tables that contain all results are provided in Appendix F, and the laboratory reports 

are provided in Appendix D. 

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 15 September

2021 (Assistant Secretary of Defense, 2021). The ARNG program under which this SI was 

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

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

under CERCLA. The SLs established in the OSD memorandum apply to three compounds: 

PFOS, PFOA, and PFBS. 

The SLs are presented on Table 6-1 below. All other results presented in this report are 

considered informational in nature and serve as an indication as to whether soil and groundwater

contain or do not contain PFAS within the boundaries of the facility. 

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

Analyte

Residential

(Soil)

(μg/kg)a,b 

0-2 feet bgs

Industrial/ 

Commercial 

Composite 

Worker 

(Soil)

(μg/kg)a,b 

2-15 feet bgs

Tap Water

(Groundwater) 

(ng/L)a,b

PFOA 130 1,600 40

PFOS 130 1,600 40

PFBS 1,900 25,000 600

Notes:

a.) Assistant Secretary of Defense, 2021. Risk Based Screening Levels Calculated for PFOS, PFOA, PFBS in Groundwater and Soil using 

United States Environmental Protection Agency’s (USEPA’s) Regional Screening Level Calculator. Hazard Quotient (HQ) = 0.1. 15

September 2021. 

b.) USEPA, 2021. Risk Based Screening Levels Calculated for PFBS in Groundwater and Soil using USEPA’s Regional Screening Level 

Calculator. HQ = 0.1. 8 April 2021.

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

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

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

receptors identified at the site: 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. 
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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 of PFAS contaminants. According to the Interstate 

Technology Regulatory Council (ITRC), several important PFAS partitioning mechanisms include 

hydrophobic and lipophobic effects, electrostatic interactions, and interfacial behaviors. At 

relevant environmental pH values, certain PFAS are present as organic anions and are therefore 

relatively mobile in groundwater (Xiao et al., 2015), but tend to associate with the organic carbon 

fraction that may be present in soil or sediment (Higgins and Luthy 2006; Guelfo and Higgins, 

2013). When sufficient organic carbon is present, organic carbon normalized distribution 

coefficients (Koc values) can help in evaluating transport potential, though other geochemical 

factors (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, which includes one potential PFAS release area: the TriMaxTM Storage and Ramp Area. The 

detected compounds in soil and groundwater are summarized on Table 6-2 through Table 6-4. 

The detections of PFOA, PFOS, and PFBS in soil and groundwater are presented on Figure 6-1

through Figure 6-4. 

6.3.1 AOI 1 Soil Analytical Results

PFOA, PFOS, and PFBS did not exceed the SLs in soil at the potential PFAS release area: 

TriMaxTM Storage and Ramp Area. Figure 6-1 through Figure 6-3 present the ranges of 

detections of PFOA, PFOS, and PFBS in soil. Table 6-2 through Table 6-3 summarize the 

detected compounds in soil.

At AOI 1, soil was sampled from surface soil (0 to 2 feet bgs), shallow subsurface soil (4 to 6 feet 

bgs and 6 to 8 feet bgs), and deep subsurface soil (6 to 8 feet bgs and 13 to 15 feet bgs) from 

boring locations AOI01-02 and AOI01-04. Soil was sampled from surface (0 to 2 feet bgs) and

shallow subsurface (2 to 4 feet bgs) soil at locations AOI01-01 and AOI01-03. PFOA, PFOS, and 

PFBS were detected in surface soil at AOI01-02 at 0.518 J micrograms per kilogram (μg/kg), 

0.158 J μg/kg, and 0.044 J μg/kg, respectively. No other surface soil location at AOI 1 exhibited 

detections of PFOA, PFOS, and PFBS. In shallow subsurface soil, PFOA was detected at AOI01-

02, at a concentration of 0.404 J μg/kg. PFOA, PFOS, and PFBS were not detected at any other 

shallow subsurface sample location or at any deep subsurface soil sample location.

6.3.2 AOI 1 Groundwater Analytical Results

PFOA, PFOS, and PFBS in groundwater did not exceed the SLs at any of the four groundwater 

sample locations at AOI 1: AOI01-01 (screened from 5-10 feet bgs), AOI01-02 (screened from 5-

15 feet bgs), AOI01-03 (screened from 5-15 feet bgs), and AOI01-04 (screened from 10-20 feet 

bgs). Figure 6-4 presents the ranges of detections of PFOA, PFOS, and PFBS in groundwater. 

Table 6-4 summarizes the detected compounds in groundwater.

Within the potential PFAS release area at AOI 1, groundwater was sampled from temporary 

monitoring well locations AOI01-01 through AOI01-04. The SLs for PFOA, PFOS, and PFBS in 

groundwater were not exceeded at any sample location. PFOA was detected at AOI01-01 at 16.4
FINAL Site Inspection Report

AASF1, Green Township, Summit County, Ohio

AECOM 6-3

nanograms per liter (ng/L) and at AOI01-03 at 1.75 J ng/L. PFOS was detected at AOI01-01 at a 

concentration of 1.22 J ng/L and at AOI01-03 at 2.28 J ng/L. PFBS was detected at each sample 

location other than AOI01-04, at concentrations ranging from 1.29 J ng/L to 3.31 J ng/L.

Groundwater analytical results at AOI 1 are consistent with the soil detections observed in this 

area.

6.3.3 AOI 1 Conclusions

Based on the results of the SI, PFOA, PFOS, and PFBS were detected in soil at AOI 1; however, 

the detected concentrations were at least two orders of magnitude lower than their respective soil 

SLs. PFOA, PFOS, and PFBS were detected in groundwater at AOI 1 at concentrations below 

their respective groundwater SLs. Based on the soil and groundwater results from this SI, no 

further investigation 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, which includes one potential PFAS release area, the Green AASF 1 Hangar. The detected 

compounds in soil and groundwater are summarized on Table 6-2 through Table 6-4. The 

detections of PFOA, PFOS, and PFBS in soil and groundwater are presented on Figure 6-1

through Figure 6-4.

6.4.1 AOI 2 Soil Analytical Results

PFOA, PFOS, and PFBS did not exceed the SLs in soil at the potential release area, Green 

AASF1 Hangar. Figure 6-1 through Figure 6-3 present the ranges of detections of PFOA, PFOS, 

and PFBS in soil. Table 6-2 through Table 6-3 summarize the detected compounds in soil.

At the Green AASF1 Hangar, soil was sampled from surface soil (0 to 2 feet bgs) at locations 

AOI02-01, AOI02-02, AOI02-03, and AOI02-04. Due to variations in groundwater level at AOI 2, 

shallow subsurface and deep subsurface soil samples were taken at varying depths:

• AOI02-01 shallow subsurface soil was collected from 2 to 4 feet bgs and 7 to 9 feet bgs, and the 

deep subsurface soil sample was collected from 13 to 15 feet bgs. 

• AOI02-02 shallow subsurface soil was collected from 4 to 6 feet bgs, and deep subsurface soil

was collected from 8 to 10 feet bgs. 

• AOI02-03 shallow subsurface soil was collected from 2 to 4 feet bgs, and deep subsurface soil

was collected from 4 to 6 feet bgs. 

• AOI02-04 shallow subsurface soil was collected from 6 to 8 feet bgs, and deep subsurface soil 

was collected from 13 to 15 feet bgs. 

PFOA, PFOS, and PFBS were not detected in any soil depth interval at AOI02-01. At AOI02-02, 

PFOS and PFBS were detected in surface soil at concentrations of 0.066 J μg/kg and 0.027 J 

μg/kg. PFOS, PFOA, and PFBS were not detected at AOI02-02 in shallow or deep subsurface 

soil. At AOI02-03, PFOS, PFOA, and PFBS were all detected in surface soil at concentrations of 

0.329 J μg/kg, 0.150 J μg/kg, and 0.055 J μg/kg, respectively. Similarly, PFOS, PFOA, and PFBS 

were detected in shallow subsurface soil at AOI02-03 at concentrations of 0.205 J+ μg/kg, 0.127 

J μg/kg, and 0.051 J μg/kg, respectively. PFOS and PFBS were detected in deep subsurface soil 

at AOI02-03 at concentrations of 0.137 J μg/kg and 0.023 J μg/kg, respectively. At AOI02-04, 

PFBS was detected in surface soil at a concentration of 0.046 J μg/kg. PFOS and PFOA were not 

detected in surface soil. Similarly, PFOS, PFOA, and PFBS were not detected in shallow 

subsurface or deep subsurface soil.
FINAL Site Inspection Report

AASF1, Green Township, Summit County, Ohio

AECOM 6-4

6.4.2 AOI 2 Groundwater Analytical Results

PFOA, PFOS, and PFBS in groundwater did not exceed SLs at AOI 2. Figure 6-4 presents the 

ranges of detections for PFOA, PFOS, and PFBS in groundwater. Table 6-4 summarizes the 

detected compounds in groundwater.

Within the Green AASF1 Hangar potential PFAS release area, groundwater was sampled from 

temporary monitoring well locations AOI02-01 (screened from 15-25 feet bgs), AOI02-02 

(screened from 5-15 feet bgs) and AOI02-03 (screened from 5-10 feet bgs). No groundwater SLs 

were exceeded at any temporary well location. PFOS was only detected at AOI02-03 at a 

concentration of 12.9 J ng/L. PFOA was detected at AOI02-01 and AOI02-03 at concentrations 

ranging from 2.95 J ng/L and 9.86 J ng/L. PFBS was detected below the groundwater SL at AOI02-

02 and AOI02-03 at concentrations of 1.05 J ng/L and 24.0 J ng/L, respectively. Groundwater 

concentrations of PFOA, PFOS, and PFBS are consistent with soil concentrations observed in 

this area.

6.4.3 AOI 2 Conclusions

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

at AOI 2; however, the detected concentrations were below their respective soil and groundwater 

SLs. Based on the soil and groundwater results from this SI, no further investigation 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, which includes one potential PFAS release area, the wetland, where on-facility drainage 

discharges. The detected compounds in soil and groundwater are presented in Table 6-2 through 

Table 6-4. The detections of PFOA, PFOS, and PFBS in soil and groundwater are presented on 

Figure 6-1 through Figure 6-4.

6.5.1 AOI 3 Soil Analytical Results

PFOA, PFOS, and PFBS in soil did not exceed the SLs in soil at the potential PFAS release area 

in AOI 3. Figure 6-1 through Figure 6-3 present the ranges of detections of PFOA, PFOS, and 

PFBS in soil. Table 6-2 through Table 6-3 summarize the detected compounds in soil.

At AOI 3, soil was sampled from three intervals at one location, AOI03-01. PFOA and PFOS were 

detected at concentrations two orders of magnitude below the SLs. PFBS was not detected in 

AOI 3. PFOA and PFOS were detected in surface soil (0 to 2 feet bgs) at concentrations of 0.193 

J μg/kg and 0.146 J μg/kg, respectively. At AOI 3, PFOA, PFOS, and PFBS were not detected in 

shallow subsurface (2 to 4 feet bgs) or deep (4 to 6 feet bgs) subsurface soil samples.

6.5.2 AOI 3 Groundwater Analytical Results

PFOA, PFOS, and PFBS did not exceed groundwater SLs at the one groundwater sample 

collected from AOI 3. Figure 6-4 presents the ranges of detections for PFOA, PFOS, and PFBS 

in groundwater. Table 6-4 summarizes the detected compounds in groundwater.

At AOI 3, groundwater was sampled from one temporary monitoring well location, AOI03-01

(screened from 5-15 feet bgs). PFOA, PFOS, and PFBS were detected at concentrations of 4.40 

J ng/L, 3.20 J ng/L, and 2.64 J ng/L, respectively. Groundwater concentrations of PFOA, PFOS, 

and PFBS are consistent with soil concentrations observed in this area.
FINAL Site Inspection Report

AASF1, Green Township, Summit County, Ohio

AECOM 6-5

6.5.3 AOI 3 Conclusions

Based on the results of the SI, PFOA and PFBS were detected in surface soil at AOI 3 at 

concentrations below their respective SLs, and PFBS was not detected in soil. PFOA, PFOS, and 

PFBS were detected in groundwater at concentrations below their respective SLs. Based on the 

soil and groundwater results from this SI, no further investigation of AOI 3 is warranted.
FINAL Site Inspection Report

AASF1, Green Township, Summit County, Ohio

AECOM 6-6

THIS PAGE INTENTIONALLY BLANK
Table 6-2

PFAS Detections in Surface Soil

Site Inspection Report, Green Armory AASF1

Analyte OSD Screening 

Level a

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

PFBA - 0.134 J 0.151 J 0.090 J ND ND ND 0.102 J ND PFBS 1900 ND UJ 0.044 J ND ND ND 0.027 J 0.055 J 0.046 

PFHpA - 0.175 J 0.057 J ND ND ND ND 0.040 J ND 

PFHxA - 0.329 J 0.085 J ND ND ND 0.026 J 0.053 J ND 

PFHxS - ND UJ 0.048 J ND 0.038 J ND ND 0.032 J ND 

PFNA - ND UJ ND UJ ND ND ND ND 0.032 J ND 

PFOA 130 ND UJ 0.518 J ND ND ND ND 0.150 J ND 

PFOS 130 ND UJ 0.158 J ND ND ND 0.066 J 0.329 J ND 

PFPeA - 0.634 J 0.071 J 0.177 J ND ND 0.024 J 0.047 J ND 

Grey Fill Detected concentration exceeded OSD Screening Levels Chemical Abbreviations

PFBA perfluorobutanPFBS perfluorobutanPFHpA perfluorohepta

References PFHxA perfluorohexa

PFHxS perfluorohexaPFNA perfluorononaPFOA perfluorooctanPFOS perfluorooctanPFPeA perfluoropentaAcronyms and Abbreviations

Interpreted Qualifiers AASF Army Aviation 

J = Estimated concentration AOI Area of Interes

J+ = Estimated concentration, biased high ft feet

UJ = The analyte was not detected at a level greater than or equal to the adjusted detection limit (DL). However, the reported adjusted DL is approximate and may be inaccurate or imprecise. GRN Green

HQ hazard quotienLCMSMS liquid chromatLOD limit of detectioND analyte not deOSD Office of the SQSM Quality SystemQual interpreted quSB soil boringUSEPA United States μg/kg micrograms pe- not applicable

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

a. Assistant Secretary of Defense, 2021. Risk Based Screening Levels Calculated for PFBS, PFOS, and PFOA in Groundwater or Soil using USEPA’s Regional Screening Level Calculator. HQ=0.1. 15 September 2021. Soil screening levels based on residential scenario for direct ingestion of contaminated soil.

AOI 1 AOI 2

GRN-AOI0

06/1

0 

GRN-AOI02-02-SB-0-2

06/17/2021

0 - 2 ft

GRN-AOI02-03-SB-0-2

06/16/2021

0 - 2 ft

GRN-AOI01-04-SB-0-2

06/17/2021

0 - 2 ft

GRN-AOI02-01-SB-0-2

06/16/2021

0 - 2 ft

GRN-AOI01-02-SB-0-2

06/17/2021

0 - 2 ft

GRN-AOI01-03-SB-0-2

06/17/2021

0 - 2 ft

Area of Interest

Sample ID

Sample Date

Depth

GRN-AOI01-01-SB-0-2

06/17/2021

0 - 2 ft

AECOM 
Table 6-3

PFAS Detections in Subsurface Soil

Site Inspection Report, Green AASF1

Analyte OSD Screening 

Level a

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

Soil, PFAS by LCMSMS compliant with QSM 5.3 Table B-15 (μg/kg)6:2 FTS - ND ND ND ND ND ND ND PFBA - ND ND UJ 0.247 J ND 0.075 J ND UJ ND 

PFBS 25000 ND ND ND ND ND ND ND PFDoA - ND ND ND ND ND ND ND PFHpA - ND ND UJ 0.195 J ND 0.060 J 0.026 J ND PFHxA - ND ND UJ 1.44 J ND 0.095 J 0.039 J ND PFHxS - ND ND ND ND ND ND ND PFNA - ND ND UJ 0.036 J ND ND ND ND PFOA 1600 ND ND UJ 0.404 J ND ND ND ND PFOS 1600 ND ND ND ND ND ND ND PFPeA - ND ND UJ 0.599 J ND 0.175 J 0.069 J 0.035 J 

Grey Fill Detected concentration exceeded OSD Screening Levels Chemical Abbreviations

6:2 FTS PFBA PFBS 

References PFDoA 

PFHpA PFHxA PFHxS PFNA PFOA PFOS PFPeA 

Interpreted Qualifiers

J = Estimated concentration Acronyms and AbbreviationJ- = Estimated concentration, biased low AASF J+ = Estimated concentration, biased high AOI UJ = The analyte was not detected at a level greater than or equal to the adjusted detection limit (DL). However, the reported adjusted DL is approximate and may be inaccurate or imprecise. DUP 

ft GRN HQ LCMSMS LOD ND OSD QSM Qual SB USEPA μg/kg - 

a. Assistant Secretary of Defense, 2021. Risk Based Screening Levels Calculated for PFBS, PFOS, and PFOA in Groundwater or Soil using USEPA’s Regional Screening Level Calculator. HQ=0.1. 15 September 2021. Soil screening levels based on industrial/commercial composite worker scenario for incidental ingestion of contaminated soil.

GRN-AOI01-02-SB-4-6

06/17/2021

4 - 6 ft

GRN-AOI01-02-SB-4-6-DUP

06/17/2021

4 - 6 ft

GRN-AOI01-03-SB-2-4

06/17/2021

2 - 4 ft

GRN-AOI01-03-SB-2-4-DUP

06/17/2021

GRN-AOI01-02-SB-6-8

06/17/2021

6 - 8 ft

GRN-AOI01-04-SB-6

06/17/2021

2 - 4 ft 6 - 8 ft

Area of Interest

Sample ID

Sample Date

Depth

GRN-AOI-01-01-SB-2-4

08/24/2021

2 - 4 ft

AOI 1

AECOM 
Table 6-3

PFAS Detections in Subsurface Soil

Site Inspection Report, Green AASF1

Analyte OSD Screening 

Level a

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

Soil, PFAS by LCMSMS compliant with QSM 5.3 Table B-15 (μg/kg)6:2 FTS - ND 0.154 J ND ND ND ND ND ND PFBA - ND ND ND UJ ND ND 0.043 J ND ND PFBS 25000 ND ND ND ND ND 0.051 J 0.023 J ND 

PFDoA - ND ND ND UJ ND ND ND ND ND PFHpA - ND ND ND ND ND 0.034 J 0.022 J ND PFHxA - ND ND ND ND ND 0.069 J 0.045 J 0.03

PFHxS - ND ND ND ND 0.077 J 0.066 J 0.062 J ND 

PFNA - ND ND ND ND ND 0.024 J ND ND PFOA 1600 ND ND ND ND ND 0.127 J ND ND PFOS 1600 ND ND ND ND ND 0.205 J+ 0.137 J ND 

PFPeA - ND ND ND UJ ND ND 0.062 J 0.035 J ND 

Grey Fill Detected concentration exceeded OSD Screening Levels Chemical Abbreviations

6:2 FTS 6:2 flPFBA perfluPFBS perflu

References PFDoA perflu

PFHpA perfluPFHxA perfluPFHxS perfluPFNA perfluPFOA perfluPFOS perfluPFPeA perflu

Interpreted Qualifiers

J = Estimated concentration Acronyms and AbbreviationsJ- = Estimated concentration, biased low AASF Army J+ = Estimated concentration, biased high AOI Area UJ = The analyte was not detected at a level greater than or equal to the adjusted detection limit (DL). However, the reported adjusted DL is approximate and may be inaccurate or imprecise. DUP dupli

ft feetGRN GreeHQ hazaLCMSMS liquid LOD limit ND analyOSD OfficQSM QualQual interpSB soil bUSEPA Uniteμg/kg micro- not a

GRN-AOI02-02-SB-8-10

06/17/2021

8 - 10 ft

G

06/16/2021 

4 - 6 ft

a. Assistant Secretary of Defense, 2021. Risk Based Screening Levels Calculated for PFBS, PFOS, and PFOA in Groundwater or Soil using USEPA’s Regional Screening Level Calculator. HQ=0.1. 15 September 2021. Soil screening levels based on industrial/commercial composite worker scenario for incidental ingestion of contaminated soil.

GRN-AOI02-03-SB-2-4

06/16/2021

2 - 4 ft

GRN-AOI02-01-SB-13-15

06/16/2021

13 - 15 ft

Area of Interest

Sample ID

Sample Date

Depth

GRN-AOI02-02-SB-4-6

06/17/2021

4 - 6 ft

AOI 2

GRN-AOI02-01-SB-7-9

06/16/2021

7 - 9 ft

GRN-AOI02-02-SB-4-6-DUP

06/17/2021

4 - 6 ft

GRN-AOI02-03-SB-4-6

AECOM 
Table 6-3

PFAS Detections in Subsurface Soil

Site Inspection Report, Green AASF1

Analyte OSD Screening 

Level a

Result Qual Result Qual

Soil, PFAS by LCMSMS compliant with QSM 5.3 Table B-15 (μg/kg)6:2 FTS - ND NDPFBA - ND NDPFBS 25000 ND NDPFDoA - 0.031 J NDPFHpA - ND NDPFHxA - ND NDPFHxS - ND NDPFNA - ND NDPFOA 1600 ND NDPFOS 1600 ND NDPFPeA - ND ND

Grey Fill Detected concentration exceeded OSD Screening Levels Chemical Abbreviations

6:2 FTS 6:2 fluorotePFBA perfluorobuPFBS perfluorobu

References PFDoA perfluorodo

PFHpA perfluorohePFHxA perfluorohePFHxS perfluorohePFNA perfluoronoPFOA perfluoroocPFOS perfluoroocPFPeA perfluorope

Interpreted Qualifiers

J = Estimated concentration Acronyms and AbbreviationsJ- = Estimated concentration, biased low AASF Army AviatJ+ = Estimated concentration, biased high AOI Area of InteUJ = The analyte was not detected at a level greater than or equal to the adjusted detection limit (DL). However, the reported adjusted DL is approximate and may be inaccurate or imprecise. DUP duplicate

ft feetGRN GreenHQ hazard quoLCMSMS liquid chromLOD limit of deteND analyte not OSD Office of thQSM Quality SysQual interpreted SB soil boringUSEPA United Statμg/kg micrograms - not applica

a. Assistant Secretary of Defense, 2021. Risk Based Screening Levels Calculated for PFBS, PFOS, and PFOA in Groundwater or Soil using USEPA’s Regional Screening Level Calculator. HQ=0.1. 15 September 2021. Soil screening levels based on industrial/commercial composite worker scenario for incidental ingestion of contaminated soil.

AOI 3

Depth 2 - 4 ft 4 - 6 ft

Sample Date 06/17/2021 06/17/2021

Sample ID GRN-AOI03-01-SB-2-4 GRN-AOI03-01-SB-4-6

Area of Interest

AECOM 
Table 6-4

PFAS Detections in Groundwater

Site Inspection Report, Green Armory AASF1

Analyte OSD Screening 

Level a

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

6:2 FTS - 2.69 J ND UJ ND UJ ND ND UJ ND UJ ND ND UJ N

PFBA - 178 ND UJ 12.7 J ND 16.3 J 15.3 J ND 7.25 J 5

PFBS 600 3.31 J 1.57 J 1.29 J ND ND UJ ND UJ 1.05 J 24.0 J 2PFHpA - 162 ND UJ 5.06 J 1.46 J ND UJ ND UJ ND 7.96 J NPFHxA - 583 ND UJ 19.9 J 4.12 1.52 J 1.32 J ND 7.78 J 0

PFHxS - ND ND UJ 2.32 J ND ND UJ ND UJ ND 14.9 J 1PFNA - 2.30 J ND UJ ND UJ ND ND UJ ND UJ ND 3.29 J NPFOA 40 16.4 ND UJ 1.75 J ND 3.52 J 2.95 J ND 9.86 J 4PFOS 40 1.22 J ND UJ 2.28 J ND ND UJ ND UJ ND 12.9 J 3PFPeA - 1240 ND UJ 39.1 J 7.38 2.23 J 2.01 J ND 13.0 J N

Total PFOA+PFOS - 17.6 ND 4.03 ND 3.52 2.95 ND 22.8 7

Grey Fill Detected concentration exceeded OSD Screening Levels Chemical AbbreviationsBold Font Detected concentration exceeded USEPA HA Screening Levels 6:2 FTS 6:2 fluorotelomer sulfonate

PFBA perfluorobutanoic acidPFBS perfluorobutanesulfonic acid

References PFHpA perfluoroheptanoic acid

PFHxA perfluorohexanoic acidPFHxS perfluorohexanesulfonic acidPFNA perfluorononanoic acidPFOA perfluorooctanoic acidPFOS perfluorooctanesulfonic acidPFPeA perfluoropentanoic acid

Interpreted Qualifiers

J = Estimated concentration Acronyms and AbbreviationsUJ = The analyte was not detected at a level greater than or equal to the adjusted detection limit (DL). However, the reported adjusted DL is approximate and may be inaccurate or imprecise. AASF Army Aviation Support Facility

AOI Area of InterestDUP duplicateGRN GreenGW groundwaterHA Health AdvisoryHQ hazard quotientLCMSMS liquid chromatography with tandem mass spLOD limit of detectionND analyte not detected above the LODOSD Office of the Secretary of DefenseQSM Quality Systems ManualQual interpreted qualifierUSEPA United States Environmental Protection Ageng/L nanogram per liter- not applicable

Area of Interest

Sample ID

Sample Date

GRN-AOI01-01-GW

06/18/2021 06/17/2021

GRN-AOI01-02-GW

06/17/2021

GRN-AOI01-03-GW

06/17/2021

a. Assistant Secretary of Defense, 2021. Risk Based Screening Levels Calculated for PFBS, PFOS, and PFOA in Groundwater or Soil using USEPA’s Regional Screening Level Calculator. HQ=0.1. 15 September 2021. Groundwater screening levels based on residential scenario for direct ingestion of groundwater.

Water, PFAS by LCMSMS compliant with QSM 5.3 Table B-15 (ng/L)

AOI 1 AOI 2

GRN-AOI02-03-GW

06/17/2021

GRN-AOI02-01-GW-DUP

06/17/2021

GRN-AOI02-02-GW

06/18/2021

GRN-AOI01-04-GW

06/18/2021

GRN-AOI02-01-GW

AECOM 
FINAL Site Inspection Report

AASF1, Green Township, Summit County, Ohio

AECOM 6-12

THIS PAGE INTENTIONALLY BLANK
AOI01-01

AOI01-02

AOI02-01 AOI02-02

AOI02-03

AOI03-01

AOI01-04

AOI01-03

AOI02-04

AOI01-01

AOI01-02

AOI02-01 AOI02-02

AOI02-03

AOI03-01

AOI01-04

AOI01-03

AOI02-04

AOI01-02

AOI02-01 AOI02-02

AOI02-03

AOI03-01

AOI01-04

AOI02-04

­ Figure 6-1

PFOA Detections in Soil

12420 Milestone Center Drive

Germantown, MD 20876

Legend

Facility Boundary

CLIENT

REVISED

SCALE

PROJECT

ARNG

Site Inspection for PFAS at AASF1, OH

12/10/2021

12/10/2021

12/10/2021

MS

EG

CM

GIS BY

CHK BY

PM

Base Map: Source: Esri, Maxar, GeoEye, Earthstar Geographics, CNES/Airbus DS,

USDA, USGS, AeroGRID, IGN, and the GIS User Community

12/10/2021

1:4,800

C:\Users\stankevichm\OneDrive - AECOM Directory\ARNG_PFAS_GIS_60552172\MXDs\OH\Green_Armory_Figures\Green_Armory_SI_Figures\SI_Report\Results\Fig_6-1_Green_AASF1_SI_Soil_Results_PFOA.mxd

0 200 400 800

Feet

Shallow Intermediate Deep

PFOA Results (μg/Kg)

ND

>ND - 10

>10 - 130

>130 - 1,600

>1,600

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

AECOM 6-13
AOI01-01

AOI01-02

AOI02-01 AOI02-02

AOI02-03

AOI03-01

AOI01-04

AOI01-03

AOI02-04

AOI01-01

AOI01-02

AOI02-01 AOI02-02

AOI02-03

AOI03-01

AOI01-04

AOI01-03

AOI02-04

AOI01-02

AOI02-01 AOI02-02

AOI02-03

AOI03-01

AOI01-04

AOI02-04

­ Figure 6-2

PFOS Detections in Soil

12420 Milestone Center Drive

Germantown, MD 20876

Legend

Facility Boundary

CLIENT

REVISED

SCALE

PROJECT

ARNG

Site Inspection for PFAS at AASF1, OH

12/10/2021

12/10/2021

12/10/2021

MS

GC

CM

GIS BY

CHK BY

PM

Base Map: Source: Esri, Maxar, GeoEye, Earthstar Geographics, CNES/Airbus DS,

USDA, USGS, AeroGRID, IGN, and the GIS User Community

12/10/2021

1:4,800

C:\Users\stankevichm\OneDrive - AECOM Directory\ARNG_PFAS_GIS_60552172\MXDs\OH\Green_Armory_Figures\Green_Armory_SI_Figures\SI_Report\Results\Fig_6-2_Green_AASF1_SI_Soil_Results_PFOS.mxd

0 200 400 800

Feet

Shallow Intermediate Deep

PFOS Results (μg/Kg)

ND

>ND - 10

>10 - 130

>130 - 1,600

>1,600

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

AECOM 6-14
AOI01-01

AOI01-02

AOI02-01 AOI02-02

AOI02-03

AOI03-01

AOI01-04

AOI01-03

AOI02-04

AOI01-01

AOI01-02

AOI02-01 AOI02-02

AOI02-03

AOI03-01

AOI01-04

AOI01-03

AOI02-04

AOI01-02

AOI02-01 AOI02-02

AOI02-03

AOI03-01

AOI01-04

AOI02-04

­ Figure 6-3

PFBS Detections in Soil

12420 Milestone Center Drive

Germantown, MD 20876

Legend

Facility Boundary

CLIENT

REVISED

SCALE

PROJECT

ARNG

Site Inspection for PFAS at AASF1, OH

12/10/2021

12/10/2021

12/10/2021

MS

GC

CM

GIS BY

CHK BY

PM

Base Map: Source: Esri, Maxar, GeoEye, Earthstar Geographics, CNES/Airbus DS,

USDA, USGS, AeroGRID, IGN, and the GIS User Community

12/10/2021

1:4,800

C:\Users\stankevichm\OneDrive - AECOM Directory\ARNG_PFAS_GIS_60552172\MXDs\OH\Green_Armory_Figures\Green_Armory_SI_Figures\SI_Report\Results\Fig_6-3_Green_AASF1_SI_Soil_Results_PFBS.mxd

0 200 400 800

Feet

Shallow Intermediate Deep

PFBS Results (μg/Kg)

ND

>ND - 10

>10 - 1,900

>1,900 - 25,000

>25,000

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

AECOM 6-15
AOI01-01

AOI01-02

AOI02-01 AOI02-02

AOI02-03

AOI03-01

AOI01-04

AOI01-03

AOI01-01

AOI01-02

AOI02-01 AOI02-02

AOI02-03

AOI03-01

AOI01-04

AOI01-03

AOI01-01

AOI01-02

AOI02-01 AOI02-02

AOI02-03

AOI03-01

AOI01-04

AOI01-03

­ Figure 6-4

PFOA, PFOS, and PFBS Detections in Groundwater

12420 Milestone Center Drive

Germantown, MD 20876

Legend

Facility Boundary

Groundwater Flow Direction

CLIENT

REVISED

SCALE

PROJECT

ARNG

Site Inspection for PFAS at AASF1, OH

12/10/2021

12/10/2021

12/10/2021

MS

EG

CM

GIS BY

CHK BY

PM

Base Map: Source: Esri, Maxar, GeoEye, Earthstar Geographics, CNES/Airbus DS,

USDA, USGS, AeroGRID, IGN, and the GIS User Community

12/10/2021

1:4,800

C:\Users\stankevichm\OneDrive - AECOM Directory\ARNG_PFAS_GIS_60552172\MXDs\OH\Green_Armory_Figures\Green_Armory_SI_Figures\SI_Report\Results\Fig_6-4_Green_AASF1_SI_GW_Results.mxd

0 200 400 800

Feet

PFOA PFOS PFBS

PFOA Results (ng/L)

ND

>ND - 10

>10 - 40

>40 - 70

>70 - 400

>400

PFOS Results (ng/L)

ND

>ND - 10

>10 - 40

>40 - 70

>70 - 400

>400

PFBS Results (ng/L)

ND

>ND - 10

>10 - 600

>600 - 1,000

>1,000 - 6,000

>6,000

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

AECOM 6-16
FINAL Site Inspection Report

AASF1, Green Township, Summit County, Ohio

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. 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 

PFOA, PFOS, or PFBS 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 PFOA, PFOS, 

or PFBS above the SLs. Areas with an identified potentially complete pathway may warrant further 

investigation. 

In general, the potential routes of exposure to PFAS 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 PFAS 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 for PFOA, PFOS, and PFBS in soil were used to determine whether a potentially 

complete pathway exists between the source and potential receptors at AOI 1, AOI 2, and AOI 3

based on the aforementioned criteria. 

7.1.1 AOI 1

From at least 2006 to 2018, PFAS were potentially released at the TriMaxTM Storage and Ramp 

area due to leaks or spills. PFOA, PFOS, and PFBS were detected below the SLs in soil at AOI 

1 and confirm the release of PFAS to soil.

Based on the results of the SI in AOI 1, ground-disturbing activities could potentially result in site

worker, construction worker, or trespasser exposure to PFOA, PFOS, and PFBS via inhalation of 

dust. Off-facility recreational users may be potentially exposed to PFOA, PFOS, and PFBS via 

inhalation of dust caused by on-facility ground disturbing activities. Ground-disturbing activities 

could also potentially result in site worker, construction worker, or trespasser exposure via 

ingestion of surface soil. Lastly, ground-disturbing activities could also potentially result in 
FINAL Site Inspection Report

AASF1, Green Township, Summit County, Ohio

AECOM 7-2

construction worker exposure to PFOA in subsurface soil via ingestion. There is no ongoing 

construction at Green AASF1; however, future construction activities may include ground 

disturbing activities. The AOI 1 CSM is presented on Figure 7-1. 

7.1.2 AOI 2 

The Green AASF1 Hangar was constructed between 1987 and 1988. The Hangar was retrofitted 

in 2006 to include a HEF fire suppression system, and a test was conducted in 2007 that resulted 

in a full release of the system. During the test of the fire suppression system, released AFFF 

traveled to Hangar drains that connect to an OWS followed by a municipal sewer system. 

Based on the results of the SI in AOI 2, ground-disturbing activities could potentially result in site 

worker and future construction worker exposure to PFOA, PFOS, and PFBS via inhalation of dust 

or ingestion of surface soil, and future construction worker exposure to PFOA, PFOS, and PFBS 

in subsurface soil. No construction is currently occurring at AOI 2; however, future construction 

activities may include ground disturbing activities. Off-facility residents and recreational users may 

be potentially exposed to PFOA, PFOS, and PFBS via inhalation of dust caused by on-facility 

ground disturbing activities, but this exposure is likely insignificant. The CSM for AOI 2 is 

presented on Figure 7-2. 

7.1.3 AOI 3 

On-facility surface drainage empties into AOI 3, the wetland area on the southeast edge of the 

facility property that extends off-facility. While there have been no known or suspected releases 

directly to the wetland, the close proximity of AOIs 1 and 2 coupled with surface water flow 

direction to the east leaves potential for migrating PFAS to impact this wetland. PFOA and PFOS 

were detected below the SLs in soil at AOI 3 and confirm the release of PFAS to soil at AOI 3. 

Based on the results of the SI, ground-disturbing activities could potentially result in site worker, 

construction worker, and trespasser exposure to PFOA and PFOS via inhalation of dust or 

ingestion of surface soil. Off-facility residents may potentially be exposed to PFOA and PFOS via 

inhalation of dust caused by on-facility ground disturbing activities. Subsurface soil is not 

considered a potentially complete pathway, due to no detections of PFAS. Exposure to PFAS from 

AOI 3 is likely insignificant. The CSM for AOI 3 is presented on Figure 7-3. 

7.2 Groundwater Exposure Pathway

The SI results for PFOA, PFOS, and PFBS in groundwater were used to determine whether a 

potentially complete pathway exists between the source and potential receptors at AOI 1, AOI 2, 

and AOI 3 based on the aforementioned criteria.

7.2.1 AOI 1

PFOA, PFOS, and PFBS were detected in groundwater from temporary monitoring wells at levels 

below the SLs in the AOI 1 area. There are several off-facility potable wells downgradient of AOI 

1; therefore, the ingestion exposure pathway for off-facility residents and off-facility recreational 

users is considered potentially complete. Water at the facility is supplied by a public water utility 

company, not on-facility wells. Therefore, the ingestion exposure pathway for site workers and 

trespassers is considered incomplete. The ingestion pathway for future construction workers is 

potentially complete, as groundwater may be encountered during construction activities. The CSM

for AOI 1 is presented on Figure 7-1. 
FINAL Site Inspection Report

AASF1, Green Township, Summit County, Ohio

AECOM 7-3

7.2.2 AOI 2 

PFOA, PFOS, and PFBS were detected in groundwater from temporary monitoring wells below 

SLs at AOI 2. There are off-facility potable wells downgradient of AOI 2; therefore, the ingestion 

exposure pathway for off-facility residents and off-facility recreational users is potentially 

complete. The ingestion exposure pathway for site workers and trespassers is incomplete due to 

on-facility water being provided by a public utility company. While there is no ongoing construction 

at the facility, the exposure pathway for future construction workers is potentially complete as 

groundwater may be encountered during construction activities. The CSM for AOI 2 is presented 

on Figure 7-2. 

7.2.3 AOI 3 

PFOA, PFOS, and PFBS were detected in the groundwater at the lone temporary monitoring well 

at AOI 3. Though detected, PFOA, PFOS, and PFBS concentrations were all below their 

respective SLs. The ingestion exposure pathway for off-facility residents from downgradient 

potable wells is potentially complete. The ingestion pathway for site workers and trespassers is 

incomplete due to on-facility water being provided by a public utility company. There is no ongoing 

construction at the facility, but the exposure pathway for future construction workers is potentially 

complete as groundwater at the facility may be encountered during construction activities. The 

CSM for AOI 3 is presented on Figure 7-3. 
FINAL Site Inspection Report

AASF1, Green Township, Summit County, Ohio

AECOM 7-4

THIS PAGE INTENTIONALLY BLANK
Media

SOURCE PATHWAY RE

AOI 1 TriMax Storage and Ramp Area PFAS in 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 Transport and Migration Media Exposure Routes

Inhalation of 

Dust

Incidental 

Ingestion

Incidental 

Ingestion

Incidental 

Ingestion

Incidental 

Ingestion

Hum

C

Flow-Chart ContinuesPartial / Possible FlowFlow-Chart StopsIncomplete PathwayPotentially Complete PathwayPotentially Complete Pathway with Exceedance of SL

Site 

Worker

Cons

Wo

Site 

Worker

Cons

W

LEGEND

Figure 

Conceptual Si

AOI 1

Green AASF1 Site In

Potential 

Off-Facility 

Source Not 

under 

Control of 

ARNG

/

/

/ 

/ 

/ 

NOTES1. The resident and recreational usersrefer to off-site receptors.2. Inhalation of dust for off-site receptorsis likely insignificant. 3. Human consumption of fishpotentially affected by PFAS is possible.4. Active construction within AOI 1 wasoccurring as of the date of SI field work.

7-4 
Media

SOURCE PATHWAY RE

AOI 2 Hangar Release PFAS in 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 Transport and Migration Media Exposure Routes

Inhalation of 

Dust

Incidental 

Ingestion

Incidental 

Ingestion

Incidental 

Ingestion

Incidental 

Ingestion

Hum

C

Flow-Chart ContinuesPartial / Possible FlowFlow-Chart StopsIncomplete PathwayPotentially Complete PathwayPotentially Complete Pathway with Exceedance of SL

Site 

Worker

Cons

Wo

Site 

Worker

Con

W

LEGEND

Figure 

Conceptual Si

AOI 2

Green AASF1 Site In

Potential 

Off-Facility 

Source Not 

under 

Control of 

ARNG

/

/ 

/ 

// 

NOTES1. The resident and recreational usersrefer to off-site receptors.2. Inhalation of dust for off-site receptorsis likely insignificant. 3. Human consumption of fishpotentially affected by PFAS is possible.4. Active construction within AOI 1 wasoccurring as of the date of SI field work.
Media

SOURCE PATHWAY RECEPTOR

AOI 3 PFAS in 

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 Transport and Migration Media Exposure Routes

Inhalation of 

Dust

Incidental 

Ingestion

Incidental 

Ingestion

Incidental 

Ingestion

Incidental 

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 Worker4 Resident1,2 Recreational User/ Trespasser1,3

Site Worker Construction Worker4 Resident1,2 Recreational User/ Trespasser1,3

/

LEGEND

/ /

Figure 7-3

Conceptual Site Model

AOI 3

Green AASF1 Site Inspection Report

Potential 

Off-Facility 

Source Not 

under 

Control of 

ARNG

/ Wetland / /

/ /

/

/

/

/ / /

/ / /

/

/ /

NOTES

1. The resident and recreational users

refer to off-site receptors.

2. Inhalation of dust for off-site receptors

is likely insignificant.

3. Human consumption of fish

potentially affected by PFAS is possible.

4. Active construction within AOI 1 was

occurring as of the date of SI field work.

7-7
FINAL Site Inspection Report

AASF1, Green Township, Summit County, Ohio

AECOM 7-8

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FINAL Site Inspection Report

AASF1, Green Township, Summit County, Ohio

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 16 to 18 June 2021 and consisted of utility clearance, 

direct push boring, soil sample collection, temporary monitoring well installation, grab 

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

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

To fulfill the project DQOs set forth in the approved SI QAPP Addendum (AECOM, 2021a), 

samples were collected and analyzed for a subset of PFAS by LC/MS/MS compliant with QSM

5.3 Table B-15 as follows. The 18 PFAS analyzed as part of the ARNG SI program are specified 

in Section 5.7 of this Report.

• Twenty-five (25) soil samples from nine boring locations; 

• Eight grab groundwater samples from eight temporary well locations; 

• Twelve (12) quality assurance (QA) samples.

The information gathered during this investigation was used to determine if PFOA, PFOS, and/or

PFBS were present at or above SLs. Additionally, the CSMs were refined to assess whether a 

potentially complete pathway exists between the source and potential receptors for potential 

exposure to PFOA, PFOS, and PFBS at the AOIs, which are described in Section 7.

8.2 SI Goals Evaluation

As described in Section 4.2, the SI activities were designed to achieve six main goals or DQOs. 

This section describes the SI goals and the conclusions that can be made for each based on the 

data collected during this investigation. 

1. Determine the presence or absence of PFOA, PFOS, and PFBS at or above SLs.

PFOA, PFOS, and PFBS were detected at the facility in soil and groundwater. PFOA, 

PFOS, and PFBS were detected at the potential source areas as well as at the facility 

boundary near the wetland area between the potential source areas and potential drinking 

water receptors that use potable wells off-facility. No PFAS detections in soil or 

groundwater at any AOI exceeded SLs.

2. Develop information to potentially eliminate a release from further consideration because 

it is determined that it poses no significant threat to human health or the environment.

All three potential PFAS release areas were removed from further consideration based on 

the groundwater and soil data collected during this SI: the Storage and Ramp Area in AOI 

1; the Green AASF1 Hangar in AOI 2; and the Wetland in AOI 3. PFOA, PFOS, and PFBS 

were not detected in groundwater and/or soil above the SLs in any of these areas; 

therefore, these areas pose no significant threat to human health or the environment.

3. Determine the potential need for a TCRA (applies to drinking water only). The primary 

actions that will be considered include provision of alternative water supplies or wellhead 

treatment.
FINAL Site Inspection Report

AASF1, Green Township, Summit County, Ohio

AECOM 8-2

Based on the data collected during this SI, there is a potentially complete pathway 

between the potential PFAS release areas and downgradient drinking water receptors. 

However, based on detected concentrations of PFOA, PFOS, and PFBS in groundwater 

samples, there are no exceedances of the SLs. Therefore, downgradient testing of offfacility potable wells is unnecessary.

4. Collect data to better characterize the release areas for more effective and rapid initiation 

of a RI (if determined necessary).

The geological data collected as part of the SI indicate a semi-permeable and lowconductivity environment, with soils dominated by clays beyond the first few feet of sand.

Soil borings completed during the SI found well-graded sand, clay, and clayey sand as the 

dominant lithology of the soils below Green AASF1; the borings were completed at depths 

between 10 and 25 feet below ground surface (bgs). Below the first layers of sand, the 

lithology was predominantly clays, including fat clay, lean clay, and clayey sand. The clay 

layers extended the length of the boring. Some borings included sections of gravel in the 

deeper sandy layers. Samples for grain size analyses were collected at four locations, 

AOI01-01, AOI02-01, AOI03-03, and ESLR-01, and analyzed via American Society for 

Testing and Materials Method D-422. The results indicate that the soil samples are 

comprised primarily of silt (57.15 percent [%] to 75.94%) and clay (19.96% to 40.86%). 

These site observations are consistent with a clay to loam glacial till, which categorizes 

the area of the facility.

Depth to water at Green AASF1 ranges from approximately 2 to 18 feet bgs. Groundwater 

flow direction at the facility is generally to the east. These geologic and hydrogeologic 

observations inform development of technical approach for an RI, if pursued.

5. If PFOA, PFOS, and PFBS are determined to be present, aim to evaluate whether the 

concentrations can be attributed to on-facility or off-facility sources that were identified 

within 4 miles of the installation as part of the PA (e.g., fire stations, major manufacturers, 

other DoD facilities)

Based upon the evaluation of groundwater and soil results in comparison to SLs, in 

combination with the groundwater flow direction analysis, the results of the SI indicate that 

the source of detected concentrations of PFOA, PFOS, and PFBS at the facility is likely 

attributable to ARNG activities.

6. Determine whether a potentially complete pathway exists between the source and 

potential receptors and whether ARNG is the likely source of the contamination. 

Detections of PFOA, PFOS, and PFBS in soil and groundwater at potential source areas 

and the facility boundary indicate there is a potentially complete pathway between source 

and receptor. Though the exposure is likely insignificant.

8.3 Outcome 

Based on the CSMs developed and revised in light of the SI findings, there is potential for PFAS 

exposure to off-facility drinking water receptors from potential PFAS sources on facility resulting 

from historical DoD activities due to the presence of private wells in the downgradient direction, 

though exposure is likely insignificant. Sample analytical concentrations collected during the SI 

were compared against the project SLs for PFOA, PFOS, and PFBS 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, detected concentrations of PFOA, PFOS, and PFBS in groundwater at the 

Storage and Ramp potential PFAS release area were below their respective SLs. Based 

on the results of the SI, no further evaluation of AOI 1 is warranted.
FINAL Site Inspection Report

AASF1, Green Township, Summit County, Ohio

AECOM 8-3

• At AOI 2, detected concentrations of PFOA, PFOS, and PFBS in groundwater at the Green 

AASF1 Hangar potential PFAS release area were below their respective SLs. Based on 

the results of the SI, no further evaluation of AOI 2 is warranted.

• At AOI 3, detected concentrations of PFOA, PFOS, and PFBS in groundwater at the 

Wetland potential PFAS release area were below their respective SLs. Based on the 

results of the SI, no further evaluation of AOI 3 is warranted. 

• The detected concentrations of PFOA, PFOS, and PFBS in soil at all AOIs were below the 

SLs. 

Table 8-1 summarizes the SI results for soil and groundwater. Based on the CSMs developed 

and revised in light of the SI findings, there is potential for exposure to off-facility drinking water 

receptors caused by DoD activities at or adjacent to the facility, though exposure is likely 

insignificant.

Table 8-2 summarizes the rationale used to determine if an AOI should be considered for further 

investigation under CERCLA and undergo an RI. Based on the results of this SI, no further 

evaluation is warranted for AOI 1: Storage and Ramp Area, AOI 2: Green AASF1 Hangar, and 

AOI 3: Helicopter Ramp Area.
FINAL Site Inspection Report

AASF1, Green Township, Summit County, Ohio

AECOM 8-4

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FINAL Site Inspection Report 

AASF1, Green Township, Summit County, Ohio

AECOM 8-5

Table 8-1: Summary of Site Inspection Findings

AOI Potential PFAS 

Release Area

Soil –

Source Area

Groundwater –

Source Area

Groundwater –

Facility Boundary

1 Storage and Ramp Area

2 Green AASF1 Hangar N/A

3 Wetland

Legend:

N/A = Not applicable 

= PFOA, PFOS, and/or PFBS detected; exceedance of the screening levels

= PFOA, PFOS, and/or PFBS detected; no exceedance of the screening levels

= PFOA, PFOS, and PFBS not detected

Table 8-2: Site Inspection Recommendations

AOI Description Rationale Future Action

1 Storage and Ramp 

Area

Detections in groundwater but no 

exceedances of SLs. No exceedances of 

SLs in soil.

No further action

2 Green AASF1 

Hangar

Detections in groundwater but no 

exceedances of SLs. No exceedances of 

SLs in soil.

No further action

3 Wetland

Detections in groundwater but no 

exceedances of SLs. No exceedances of 

SLs in soil.

No further action
FINAL Site Inspection Report

AASF1, Green Township, Summit County, Ohio

AECOM 8-6

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FINAL Site Inspection Report 

AASF1, Green Township, Summit County, Ohio

AECOM 9-1

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, Final Preliminary Assessment Report, 

AASF1, Green Township, Summit County, Ohio. January. 

AECOM. 2021a. Final Site Inspection Uniform Federal Policy-Quality Assurance Project Plan 

Addendum, AASF1, Green Township, Summit County, Ohio, Perfluorooctane Sulfonic Acid 

(PFOS) and Perfluorooctanoic Acid (PFOA) Impacted Sites ARNG Installations, Nationwide. 

June. 

AECOM. 2021b. Final Site Safety and Health Plan, Green AASF1, North Canton, Ohio, 

Perfluorooctane Sulfonic Acid (PFOS) and Perfluorooctanoic Acid (PFOA) Impacted Sites 

ARNG Installations, Nationwide. June. 

Assistant Secretary of Defense. 2021. Investigation Per- and Polyfluoroalkyl Substances within 

the Department of Defense Cleanup Program. United States Department of Defense. 

15 October.

Aqua. 2018. “Our States: Aqua Ohio Service Territory.” Aqua America. 

https://www.aquaamerica.com/our-states/ohio.aspx. December 2018.

CHA. 2015. Akron-Canton Airport Master Plan, Final Report. September.

DA. 2016. Army Guidance to Address Perfluorooctane Sulfonate (PFOS) and Perfluorooctanoic 

Acid (PFOA) Contamination. August.

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.

Environmental Design Group (EDG). 1994. The City of Green, Ohio Comprehensive Storm Water 

Study. November 1994. 

EA Engineering, Science, and Technology, Inc. 2021. Standard Operating Procedure No. 042A 

for Treating Liquid Investigation-Derived Material (Purge water, drilling water, and 

decontamination fluids). Revision 1. March.

Guelfo, J.L. and Higgins, C.P. 2013. Subsurface transport potential of perfluoroalkyl acids ad 

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.
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AASF1, Green Township, Summit County, Ohio

AECOM 9-2

ITRC. 2018. Environmental Fate ant Transport for Per- and Polyfluoroalkyl Substances. March. 

National Oceanic and Atmospheric Administration (NOAA). 2020. “Data Tools: 1981-2010 

Normals: Akron Canton Airport, OH US.” NOAA National Centers for Environmental 

Information. https://www.ncdc.noaa.gov/cdo-web/datatools/normals. August.

Ohio Department of Natural Resources (ODNR), Division of Water Resources. 2018. Ohio Water 

Well Viewer. https://gis.ohiodnr.gov/MapViewer/?config=waterwells. December 2018. 

ODNR, Division of Water Resources. 2020. Ohio Water Well Viewer. 

https://gis.ohiodnr.gov/MapViewer/?config=waterwells. Accessed September 2020. 

Ohio Division of Geological Survey (ODGS). 1998. “Physiographic regions of Ohio.” Ohio 

Department of Natural Resources, Division of Geological Survey, page-size map with text, 2 

p., scale 1:2,100,000.

ODGS. 2004. “Shaded drift-thickness map of Ohio.” Ohio Department of Natural Resources, 

Division of Geological Survey, Map SG-3, generalized page-size version with text, scale 

1:2,000,000. Revised 2017.

Ohio Environmental Protection Agency. 2016. Investigation Derived Waste FSOP 1.7. Division of 

Environmental Response and Revitalization. August.

Schmidt, J.J. 1979. “Ground Water Resources of Summit County.” Ohio Department of Natural 

Resources, Division of Water, Ground Water Resources Section, map with text, 1 p.

Slucher, E.R., Swinford, E.M., Larsen, G.E., et al. 2006. “Bedrock Geologic Map of Ohio.” ODGS, 

Map BG-1, version 6.0, scale 1:500,000.

USACE. 2016. Technical Project Planning Process, EM-200-1-2. 26 February.

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 

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