FINAL

Preliminary Assessment Report

AASF #1 RW Shepherd,

Montgomery, Alabama

Perfluorooctanesulfonic Acid (PFOS) and Perfluorooctanoic 

Acid (PFOA) Impacted Sites

ARNG Installations, Nationwide

September 2020

Prepared for:

Army National Guard Headquarters

111 S. George Mason Drive

Arlington, VA 22204

UNCLASSIFIED
PFAS Preliminary Assessment Report

AASF #1 RW Shepherd, Montgomery, Alabama

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Table of Contents

Executive Summary .................................................................................................................... 1

1. Introduction ........................................................................................................................ 4

1.1 Authority and Purpose .............................................................................................. 4

1.2 Preliminary Assessment Methods ............................................................................. 4

1.3 Report Organization .................................................................................................. 5

1.4 Facility Location and Description............................................................................... 5

1.5 Facility Environmental Setting ................................................................................... 5

1.5.1 Geology ......................................................................................................... 6

1.5.2 Hydrogeology ................................................................................................. 6

1.5.3 Hydrology ....................................................................................................... 7

1.5.4 Climate ........................................................................................................... 7

1.5.5 Current and Future Land Use ......................................................................... 7

2. Fire Training Areas ........................................................................................................... 11

3. Non-Fire Training Areas ................................................................................................... 12

3.1 Hangar Fire Suppression System ........................................................................... 12

3.2 Hazardous Waste Storage Room ............................................................................ 12

3.3 Flight Ramp ............................................................................................................ 13

3.4 Wash Rack ............................................................................................................. 13

4. Emergency Response Areas ............................................................................................ 15

5. Adjacent Sources ............................................................................................................. 16

5.1 Interstate Industrial Park ......................................................................................... 16

5.2 Montgomery Regional Airport .................................................................................. 17

6. Preliminary Conceptual Site Model .................................................................................. 19

6.1 Pathways ................................................................................................................ 19

6.2 Receptors ............................................................................................................... 19

6.3 AOI #1: Hangar Suppression System and Mechanical Room ................................. 20

6.4 AOI #2: Flight Ramp and Wash Rack ...................................................................... 20

7. Conclusions ..................................................................................................................... 25

7.1 Findings .................................................................................................................. 25

7.2 Uncertainties ........................................................................................................... 25

7.3 Potential Future Actions .......................................................................................... 26

8. References ...................................................................................................................... 29
PFAS Preliminary Assessment Report

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Figures

Figure ES-1 Summary of Findings

Figure ES-2 Preliminary Conceptual Site Model, AASF #1 RW Shepherd

Figure 1-1 Facility Location

Figure 1-2 Groundwater Features

Figure 1-3 Surface Water Features

Figure 3-1 Non-Fire Training Areas

Figure 5-1 Adjacent Sources

Figure 6-1 Areas of Interest

Figure 6-2 Preliminary Conceptual Site Model, AOI 1 Hangar Suppression System and

Mechanical Room

Figure 6-3 Preliminary Conceptual Site Model, AOI 2 Flight Ramp and Wash Rack

Figure 7-1 Summary of Findings

Tables

Table ES-1 AOIs at AASF #1

Table 6-1 Exposure Pathways at AOI 1

Table 6-2 Exposure Pathways at AOI 2

Table 7-1 AOIs at AASF #1

Table 7-2 No Suspected Release Areas

Table 7-3 Uncertainties

Table 7-4 PA Findings Summary

Appendices

Appendix A Data Resources

A1. Environmental Data Resource Report

Appendix B Preliminary Assessment Documentation

B.1 Interview Records

B.2 Visual Site Inspection Checklists

B.3 Conceptual Site Model Information

Appendix C Photographic Log
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Acronyms and Abbreviations

°F degrees Fahrenheit

AASF Army Aviation Support Facility

AECOM AECOM Technical Services, Inc.

AFFF aqueous film forming foam

ALARNG Alabama Army National Guard

ANGB Air National Guard

AOI Area of Interest

ARNG Army National Guard

CERCLA Comprehensive Environmental Response, Compensation, and Liability

Act

CFR Code of Federal Regulations

CSM conceptual site model

CSMS combined maintenance shop

EDRTM Environmental Data Resources, IncTM.

FTA fire training area

PA Preliminary Assessment

PFAS per- and poly-fluoroalkyl substances

PFOA perfluorooctanoic acid

PFOS perfluorooctanesulfonic acid

PRL potential release location

SI Site Inspection

US United States

USACE United States Army Corps of Engineers

USEPA United States Environmental Protection Agency
PFAS Preliminary Assessment Report

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Executive Summary

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

Inspections (SIs) for Perfluorooctanesulfonic acid (PFOS) and Perfluorooctanoic acid (PFOA)

Impacted Sites at ARNG Facilities Nationwide. A PA for per- and polyfluoroalkyl substances

(PFAS)-containing materials was completed for Army Aviation Support Facility (AASF) #1 (also

referred to as the “facility”), in Montgomery, Alabama, to assess potential PFAS release areas and

exposure pathways to receptors. The AASF #1 facility is constructed on a parcel of land owned

by the Montgomery Airport Authority and leased to the Alabama ARNG (ALARNG). The

performance of this PA included the following tasks:

· Reviewed available administrative record documents and Environmental Data Resources,

Inc. (EDR)TM report packages to obtain information relevant to potential PFAS releases, such

as: drinking water well locations, historical aerial photographs, Sanborn maps, and

environmental compliance actions in the area surrounding the facility;

· Conducted a site visit 10 April 2019 and completed visual site inspections at locations where

PFAS-containing materials were suspected of being stored, used, or disposed;

· Interviewed current ALARNG personnel, including environmental managers, and operations

staff;

· Identified Area(s) of Interest (AOIs) and developed a preliminary conceptual site model (CSM)

to summarize potential source-pathway-receptor linkages of potential PFAS in soil,

groundwater, surface water, and sediment for each AOI.

Two AOIs related to potential PFAS releases were identified at the AASF #1 facility during the

PA. The AOIs are shown on Figures ES-1 and described in Table ES-1 below:

Table ES- 1 AOIs at AASF #1

Area of Interest Name Used by Potential Release Date

AOI 1 Hangar Fire Suppression

System and Mechanical Room ALARNG 1995 to present

AOI 2 Flight Ramp and Wash Rack ALARNG 2001 to 2017

Construction of the AASF #1 facility was completed in 1995. Based on aerial imagery, the

hazardous waste room was added to the west end of the hangar between 2013 and 2017. The

hangar building is equipped with the same AFFF dispensing system that was installed during the

original construction of the site; however, the 3% AFFF concentrate was replaced with the same

concentration between 2006 and 2009. The manufacturer of the historical and current 3% AFFF

concentrate could not be ascertained. The Hangar, Hazardous Waste Storage Room, Mechanical

Room, and Ramp and Wash Rack were investigated during this PA.

Based on potential PFAS releases at these AOIs, there is potential for receptor exposure to PFAS

contamination in media at or near the facility. The preliminary CSM for the facility, which presents

the potential receptors and media impacted, is shown on Figure ES-2. Based on the United States

(US) Environmental Protection Agency (USEPA) Unregulated Contaminant Monitoring Rule 3

(UCMR3) data, it was indicated that no PFAS were detected in a public water system above the

USEPA’s lifetime Health Advisories (HAs) within 20 miles of the facility. The HA is 70 parts per

trillion for PFOS and PFOA, individually or combined. PFAS analyses performed in 2016 had

method detection limits that were higher than currently achievable. Thus, it is possible that low

concentrations of PFAS were not detected during the UCMR3 but might be detected if analyzed

today.
Caney

Branch

Pin tlala

Creek

Interstate

Industrial

Park

Montgomery

Regional

Airport

Montgomery Air

National Guard

AOI 2

AOI 1

Legend

Area of Interest

Potential PFAS Release

No Suspected Release

Facility Boundary

Water Body

Stream/River

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ARNG

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Summary of Findings

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

Geographics, CNES/Airbus DS, USDA, USGS,

1:37,200

0 1,550 3,100 6,200

Feet

Wash Rack

Mechanical

Room

Hangar

Ramp

Hazardous Waste

Storage Room

AOI 2

AOI 1

Retention

Area 2

Retention

Area 1

2
Media

SOURCE PATHWAY RECEPTOR

AOI 1

AOI 2

Hangar 

Suppression 

System/

Mechanical 

Room Leaks and 

Discharge of TriMaxTM 30 Units

PFAS in 

Surface Soil

Human 

Activities

Leaching/

Infiltration

Precipitation

/ 

Run-Off

Airborne Soil 

Particulate

Surface Soil 

at AOI

Shallow 

Groundwater

Surface 

Water/ 

Sediment

Subsurface 

soil

Source Release 

Mechanism Media Transport and Migration Media Exposure Routes

Inhalation of 

Dust

Ingestion

Ingestion

Ingestion

Ingestion

Human Receptors: 

Current/ Future

Flow-Chart Continues

Partial / Possible Flow

Incomplete Pathway

Potentially Complete Pathway

Complete Pathway

Site 

Worker

Construction 

Worker Resident Recreational User

Site 

Worker

Construction 

Worker Resident Recreational User

LEGEND

/ / / /

/ / / /

Figure ES-2

Preliminary Conceptual Site Model

AASF #1 RW Shepherd

Potential 

Off-Facility 

Source Not 

under 

Control of 

ARNG

/ /

/ / /

/

/ / /

/

Notes:

1. The resident and 

recreational user 

receptors refer to an 

off-site resident and 

recreational user

2. Dermal contact 

exposure pathway is 

incomplete for PFAS

/

/

3
PFAS Preliminary Assessment Report

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1. Introduction

Authority and Purpose

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 at ARNG Facilities 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 is assessing potential effects on human health related to processes at facilities that 

used per- and poly-fluoroalkyl substances (PFAS), primarily in the form of aqueous film forming 

foam (AFFF) released as part of firefighting activities, although other PFAS sources are possible. 

In addition, the ARNG is assessing businesses or operations adjacent to the ARNG facility (not 

under the control of ARNG) that could potentially be responsible for a PFAS release. 

PFAS are classified as emerging environmental contaminants that are garnering increasing 

regulatory interest due to their potential risks to human health and the environment. PFAS 

formulations contain highly diverse mixtures of compounds. Thus, the fate of PFAS compounds 

in the environment varies. The regulatory framework at both federal and state levels continues to 

evolve. The US Environmental Protection Agency (USEPA) issued lifetime Drinking Water Health 

Advisories for PFOA and PFOS in May 2016, but there are currently no promulgated national 

standards regulating PFAS in drinking water. In the absence of federal maximum contaminant 

levels, some states have adopted their own drinking water standards for PFAS. The HA is 70 parts 

per trillion for PFOS and PFOA, individually or combined. The state of Alabama does not currently 

have drinking water standards for PFAS.

This report presents the findings of a PA for PFAS-containing materials at the current AASF #1 

(referred to as “the facility”), Montgomery, Alabama, in accordance with the Comprehensive 

Environmental Response, Compensation, and Liability Act (CERCLA), as amended, the National 

Oil and Hazardous Substances Pollution Contingency Plan (40 Code of Federal Regulations 

[CFR] Part 300), and Army requirements and guidance. 

This PA documents locations where PFAS may have been released into the environment at the 

facility. The term PFAS will be used throughout this report to encompass all PFAS chemicals being 

evaluated, including PFOS and PFOA, which are key components of AFFF. 

Preliminary Assessment Methods

The performance of this PA included the following tasks: 

· Reviewed available administrative record documents and Environmental Data Resources, 

Inc. (EDR)TM report packages to obtain information relevant to potential PFAS releases, such 

as: drinking water well locations, historical aerial photographs, Sanborn maps, and 

environmental compliance actions in the area surrounding the facility; 

· Conducted a site visit on 10 April 2019 and completed visual site inspections (VSIs) at 

locations where PFAS-containing materials were suspected of being stored, used, or 

disposed; 

· Interviewed current Alabama ARNG (ALARNG) personnel, including environmental 

managers, and operations staff; 
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· Identified Area(s) of Interest (AOIs) and developed a preliminary conceptual site model (CSM) 

to summarize potential source-pathway-receptor linkages of potential PFAS in soil, 

groundwater, surface water, and sediment for each AOI. 

Report Organization

This report has been prepared in accordance with the USEPA Guidance for Performing 

Preliminary Assessments under CERCLA (USEPA, 1991). The report sections and descriptions 

of each are as follows:

· Section 1 – Introduction: identifies the project purpose and authority and describes the 

facility location, environmental setting, and methods used to complete the PA

· Section 2 – Fire Training Areas: describes the fire training areas (FTAs) at the facility 

identified during the site visit 

· Section 3 – Non-Fire Training Areas: describes other locations of potential PFAS releases 

at the facility identified during the site visit 

· Section 4 – Emergency Response Areas: describes areas of potential PFAS release at the 

facility, specifically in response to emergency situations 

· Section 5 – Adjacent Sources: describes sources of potential PFAS release adjacent to the 

facility that are not under the control of ARNG 

· Section 6 – Preliminary Conceptual Site Model: describes the pathways of PFAS transport 

and receptors for the AOIs and the facility 

· Section 7 – Conclusions: summarizes the data findings and presents the conclusions of the 

PA 

· Section 8 – References: provides the references used to develop this document

· Appendix A – Data Resources

· Appendix B - Preliminary Assessment Documentation

· Appendix C – Photographic Log

Facility Location and Description

The facility is located in southwest Montgomery, in Montgomery County, Alabama. The facility 

property is within the Montgomery Regional Airport, at the southernmost portion of the airport 

property, off US Highway 80 (Selma Highway). The site location is depicted on (Figure 1-1). 

According to ALARNG personnel, the facility was constructed in 1995. The facility is situated on 

a 160-acre parcel of land owned by the Montgomery Airport Authority (Montgomery County, 2019). 

The current AASF #1 facilities include one hangar for the operation, maintenance, and repair of 

ALARNG rotary-winged aircraft, administrative offices, and classrooms. Water and electric utilities 

are provided by the city of Montgomery. Floor drains at the facility discharge to the oil water 

separator (OWS) and then to the stormwater sewer. According to ALARNG personnel, wastewater 

from the AASF #1 facility goes to the Cotoma Wastewater Treatment Plant (WWTP) located 

approximately 6 miles northwest of the facility.

Facility Environmental Setting

The ALARNG AASF #1 is situated in the Black Prairie Belt district of the Coastal Plain 

physiographic province. The Black Prairie Belt lies to the south and west of the Fall Line Hills and 
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occupies a crescent shaped area extending from northern Mississippi into central Alabama. The

Black Prairie Belt is characterized by an undulating, deeply-weathered plain of low relief. The

facility lies in the Southeastern Plains ecoregion, which is characterized by smooth to irregular

plains or flatlands separated in some places by curved bands of asymmetrical ridges and rugged

hills. Streams draining this ecoregion are generally low gradient with silty sand substrates. Forest

and woodland areas are prevalent and are part of the mosaic of cropland, pasture, and urban

areas that dot the landscape. Natural vegetative cover includes oak, hickory, pine, and southern

mixed forests (Geological Survey of Alabama, 2002).

1.5.1 Geology

Near-surface sediments consist of Quaternary Alluvium and Pleistocene Terrace Deposits. The

Alluvium units measures 0 to 40 feet thick and are characterized by white to light-gray, silty, poorly

sorted sand with yellow, gray-orange to bluish-gray, sandy clay lenses. The thickness of the

Terrace Deposits range from 10 to 100 feet and are characterized by pale-yellowish-orange,

cross-bedded, medium to very coarse grained, poorly-sorted sand; dark-reddish-brown sandy

clay; and lenses of well-rounded gravel (Geological Survey of Alabama, 1963).

Selma Group rocks of Late Cretaceous age unconformably underlie the Pleistocene Terrace

Deposits. Selma group rocks include all Upper Cretaceous strata above the Eutaw Formation.

Stratigraphic units of the Selma Group, in descending order, include Providence Sand, Prairie

Bluff chalk, Ripley Formation sands, Demopolis chalk, and Mooresville chalk. Units of the Selma

Group are relatively impermeable or have low groundwater permeability (Geological Survey of

Alabama, 1963).

The Eutaw Formation unconformably underlies the Mooresville Chalk of the Selma Group. The

Eutaw Formation ranges from 3 feet thick in Northeast Montgomery to 405 feet thick in southwest

Montgomery. The Eutaw formation consists of sand, light-greenish-gray, cross laminated, fine to

medium-grained, well-sorted, micaceous, glauconitic, fossiliferous sand; it is interbedded with

greenish-gray micaceous glauconitic fossiliferous clay and sandy clay. The Gordo Formation

unconformably underlies the Eutaw formation and is characterized by pale-yellowish-orange

medium to coarse grained, poorly sorted, quarzitic, ferruginous-cemented sand; it is interbedded

with moderate-reddish-brown to pale-red-purple clay. The Coker Formation unconformably

underlies the Gordo Formation and consists of light-greenish-gray, medium to coarse grained,

well-sorted, micaceous, quarzitic, glauconitic, fossiliferous sand; it is thinly laminated with

greenish-gray, lignitic, fossiliferous clay. Basement rock unconformably below the Cocker

Formation is characterized by Pre-Cretaceous crystalline, biotite, mica schist (Geological Survey

of Alabama, 1963). Geologic units underlying the facility are depicted on Figure 1-2.

1.5.2 Hydrogeology

The Quaternary Alluvium sediments yield small quantities of water of good quality in shallow wells

installed at depths from less than 10 to about 30 feet below land surface. Some users of these

wells experience water shortages during times of limited rainfall; however, some wells installed in

topographically lower areas and near streams can produce water year-round (Geological Survey

of Alabama, 1963).

Sand and Gravel beds of the Terrace Deposits are very permeable and yield moderate to large

supplies of water. Wells installed in these sand and gravel beds are used for industrial, domestic,

and stock use (Geological Survey of Alabama, 1963).

The Coker, Gordo, and Eutaw formations are the most productive aquifers in Montgomery County,

where large quantities of water are pumped from these formations for municipal use by the City

of Montgomery (Geological Survey of Alabama, 1963).
PFAS Preliminary Assessment Report

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Groundwater features surrounding the facility are shown in Figure 1-2. General groundwater flow

beneath the facility is toward the northwest. An EDRTM report conducted a well search for a 1-

mile radius surrounding the facility (Appendix A). Using additional online resources, such as state

and local Geographic Information System databases, wells were researched to a 4-mile radius of

the facility. According to the EDRTM report, no groundwater wells have been identified within a 1-

mile radius of AASF #1. Based on the USEPA Unregulated Contaminant Monitoring Rule 3 data,

it was indicated that no PFAS were detected in a public water system above the HA within 20

miles of the facility. The HA is 70 parts per trillion for PFOS and PFOA, individually or combined.

PFAS analyses performed in 2016 had method detection limits that were higher than currently

achievable. Thus, it is possible that low concentrations of PFAS were not detected during the

UCMR3 but might be detected if analyzed today.

1.5.3 Hydrology

The AASF #1 facility lies within Alabama River Basin (Geological Survey of Alabama, 2002).

General surface water drains from the facility via sheet flow to the northwest; however, surface

water could also drain to the low-lying retention areas to the southwest of the flight ramp

(Retention Area 1) and southeast of the mechanical room (Retention Area 2). There is also one

storm drain within the wash rack (east of the flight ramp) that empties to the oil/water separator

and then the sanitary sewer. The nearest named surface water body is Catoma Creek,

approximately 2.5 miles northeast, which empties into the Alabama River. Surface water features

surrounding the facility are shown in Figure 1-3.

1.5.4 Climate

Alabama’s climate is humid subtropical, with average annual temperatures in Montgomery of

about 65 degrees Fahrenheit (°F). Rainfall in Alabama usually is abundant and distributed

throughout the year. Average annual precipitation ranges from less than 50 inches to 54 inches

near Montgomery to a high of 66 inches near the coast. (Geological Survey of Alabama, 2002).

The average temperature in the area of the facility is 65 °F, with an average high of 76.5 °F and

an average low of 53.5 °F. Montgomery receives an average of 53.03 inches of rain per year

(World Climate, 2020).

1.5.5 Current and Future Land Use

The ALARNG AASF #1 facility is located within the Montgomery Regional Airport. Properties

surrounding the AASF #1 facility primarily consist of commercial properties to the north and

southeast, rural residential properties to the east and south, and agricultural properties to the

west. Reasonably anticipated future land use is not expected to change from the current land use.
^_

AASF #1 R W Shepherd Hope Hull

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Facility Location

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

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

1:126,720

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Caney Branch

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Catoma Creek

Genetta Ditch

Legend

Facility Boundary

Water Body

Wetland

Stream/River

Canal/Ditch

Inferred Groundwater Flow Direction

Geology

Alluvial and Low Terrace Deposits

Mooreville Chalk

Eutaw Formation

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

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Surface Water Features

Base Map: Source: Esri, DigitalGlobe, GeoEye,

Earthstar Geographics, CNES/Airbus DS, USDA, USGS,

1:31,680

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2. Fire Training Areas

In addition to FTAs, the PA evaluated areas where PFAS-containing materials may have been

broadly used, stored, or disposed. This may include buildings with fire suppression systems, paint

booths, AFFF storage areas, and areas of compliance demonstrations. Information on these

features obtained during the PA are included in Appendices A and B. Based on interviews

conducted during this PA, ALARNG personnel with knowledge of the property dating back to 2000

confirmed that no fire training occurred during their operation of the subject property. Features

indicative of FTAs are not evident in aerial imagery dating back to 1952 and provided in EDRTM

report (Appendix A).
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3. Non-Fire Training Areas

Non-FTAs where AFFF was stored and/or potentially released were identified during the PA. A 

description of each non-FTA is presented below and shown on Figure 3-1. 

Hangar Fire Suppression System 

The AASF #1 hangar contains a fire suppression system supplied by two 800-gallon tanks filled 

with 3% AFFF concentrate. The hangar building is equipped with an overhead suppression 

system as well as floor tanks. The current AFFF suppression system was installed in 1995 and 

was part of the original hangar construction. According to ALARNG personnel, the 3% AFFF 

concentrate was replaced with the same concentration between 2006 and 2009. The 

manufacturer of the historical and current 3% AFFF concentrate could not be ascertained. 

Additionally, information regarding where the original 3% AFFF concentrate was disposed of was 

not known by ALARNG personnel and could not be ascertained. Floor drains are located on the 

north and south ends of the hangar building. These floor drains empty to the oil/water separator 

which then discharges to the sanitary sewer.

The geographic coordinates of the hangar are 32° 17' 8.9" N; 86° 23' 41.2"W. The two 800-gallon 

concentrate tanks that supply the AFFF suppression system are located in the mechanical room, 

off the southeast corner of the hangar building. The geographic coordinates of the mechanical 

room are 32° 17' 7.9" N; 86° 23' 39.7"W. The locations of the hangar building and mechanical 

room are depicted on Figure 3-1. 

The AFFF suppression system was installed in 1995. It is reasonable to assume that an 

acceptance test was conduct prior to ALARNG accepting the system installation. According to the 

ALARNG personnel interviewed with knowledge of the property dating back to 2000, a full-scale 

test of the new system was not conducted, and the system has not been triggered. However, 

information regarding a full-scale test from 1995 to 2000 could not be ascertained. During the 

visual inspection, corrosion and rust staining were observed at both AFFF concentrate tanks in 

the mechanical room, as well as the floor tanks within the hangar building. Corrosion was not 

evident when observing the overhead suppression system in the hangar building. ALARNG 

personnel also noted that during the AFFF concentrate replacement between 2006 and 2009, an 

unknown quantity of concentrate was spilled on the south side of the mechanical room, which 

consequently killed the grass. During the visual inspection, dead grass was noted outside the 

mechanical room where the spill had occurred. Photographs are provided in Appendix C. 

Hazardous Waste Storage Room

The hazardous waste storage room is located at the west side of the hangar building. Based on 

aerial imagery, the hazardous waste room was added to the west end of the hangar between 

2013 and 2017. The geographic coordinates of the hazardous waste storage room are 32° 17' 

8.9" N; 86° 23' 42.3"W. During the PA, ALARNG personnel noted that when the AFFF concentrate 

was replaced between 2006 and 2009, the contractor responsible for replacement left a 5-gallon 

jug of 3% AFFF concentrate in the mechanical room. This jug was presumably left in the 

mechanical room to top off the 800-gallon concentrate tanks discussed above. Prior to the PA 

visit, ALARNG personnel had relocated the 5-gallon concentrate jug to the hazardous waste 

storage room. Although, AFFF is not classified as a hazardous waste, ALARNG personnel 

relocated the 5-gallon concentrate jug to the hazardous waste storage room for waste 

characterization analyses in preparation for proper disposal. Visual inspection of the 5-gallon 

concentrate jug indicated corrosion and leakage from the cap; however, the jug’s location when 

leakage occurred is unknown. It was also noted that the 5-gallon concentrate jug had been stored 

on a secondary containment. Photographs are provided in Appendix C. 
PFAS Preliminary Assessment Report

AASF #1 RW Shepherd, Montgomery, Alabama

13

Flight Ramp 

The flight ramp is located west of the hangar building. The geographic coordinates of the flight 

ramp are 32° 17' 10.6" N ; 86° 23' 46.5 "W. According to ALARNG personnel with knowledge of 

the facility dating back to 2000, approximately ten mobile AFFF Tri-MaxTM 30 units were staged 

along the flight ramp from 2001 to 2017. The Tri-MaxTM 30 units were replaced in 2017 with the 

Purple K units that are currently utilized onsite. The Tri-MaxTM units were transported offsite to the 

combined maintenance shop (CSMS) at the Alabama National Guard office in Montgomery, 

Alabama. According to CSMS personnel, the Tri-MaxTM 30 units were received empty. However, 

information regarding how the Tri-MaxTM 30 units were emptied could not be ascertained by 

ALARNG personnel at the AASF #1 facility. Based on this discrepancy, it may be assumed that 

the Tri-MaxTM 30 units were discharged on the flight ramp prior to transportation to CSMS. 

Therefore, the flight ramp is a suspected release area. Photographs of this areas are provided in 

Appendix C. 

Wash Rack

The wash rack is located south of the hangar building and is used to wash aircrafts. The 

geographic coordinates of the wash rack are 32° 17' 6.2" N; 86° 23' 40.8" W. There is one drain 

in the center of the wash rack that empties to the oil/water separator and then the municipal 

stormwater system. According to ALARNG personnel, wastewater from the AASF #1 facility goes 

to the Cotoma WWTP located approximately 6 miles northwest of the facility. According to 

ALARNG personnel with knowledge of the facility dating back to 2000, ALARNG used aircraft 

soap at the wash rack area to simulate firefighting techniques but did not use fire or AFFF for 

these simulations. As discussed in Section 3.3, approximately ten AFFF Tri-MaxTM 30 units were 

historically (from 2001 to 2017) staged along the flight ramp. Although ALARNG personnel stated 

that only aircraft soap units were used for simulating firefighting techniques, it is reasonable to 

assume that Tri-MaxTM 30 units may have been used. Therefore, there wash rack is considered a 

suspected release area. During the PA visit, an aircraft was parked in the wash rack area, 

therefore, photographs of this area could not be provided in this PA. 
Hazardous Waste

Storage Room Wash Rack

Mechanical

Room

Hangar Ramp

Retention

Area 2

Retention

Area 1

Legend

Potential PFAS Release

No Suspected Release

Facility Boundary

Water Body

Stream/River

CLIENT

REVISED

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12420 Milestone Center Drive

Germantown, MD 20876

Non-Fire Training Areas

Base Map: Source: Esri, DigitalGlobe, GeoEye,

Earthstar Geographics, CNES/Airbus DS, USDA, USGS,

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0 250 500 1,000

Feet

14
PFAS Preliminary Assessment Report

AASF #1 RW Shepherd, Montgomery, Alabama

15

4. Emergency Response Areas

No emergency response areas were identified within the AASF #1 facility during the PA through

interviews or document review. The city of Montgomery Fire Department provides fire emergency

services for the AASF #1 facility.
PFAS Preliminary Assessment Report

AASF #1 RW Shepherd, Montgomery, Alabama

16

5. Adjacent Sources

Two potential off-facility sources of PFAS adjacent to the AASF #1, not under the control of 

ALARNG, were identified during the PA. These potential off-facility sources include the Interstate 

Industrial Park and the Montgomery Regional Airport. These potential sources are depicted on 

Figure 5-1 and described below. 

Interstate Industrial Park

The Interstate Industrial Park is located approximately 2 miles southeast of the AASF #1 facility. 

The geographic coordinates for the Interstate Industrial Park are 32° 15' 49.1" N; 86° 21' 56.6" W. 

The Interstate Industrial Park is a 345-acre industrial park zoned as light industry. Businesses 

within the Interstate Industrial Park include GenPak, LLC, Hyundai Power Transformers USA, 

Inc., WestRock, and Viscofan USA, Inc. (Economic Development Partnership of Alabama, 2019). 

Brief descriptions of these companies are listed below:

· GenPak, LLC: GenPak, LLC is a distribution warehouse for containers and packaging for 

the food service industry (Genpak, 2019).

· Hyundai Power Transformers USA, Inc.: Hyundai Power Transformers USA, Inc. 

produces power transformers including oil immersed transformers, dry type transformers 

and cast resin transformers (Hyundai Power Transformers USA, 2012). 

· WestRock: Generally, WestRock produces paper and paper packaging products. The 

WestRock facility located at the Interstate Industrial Park is a warehouse and distribution 

center (WestRock, 2019). 

· Viscofan USA, Inc.: Viscofan produces casings and packaging solutions for the meat 

industry. Viscofan produces various casing materials including cellulose, collagen, fibrous 

and plastic (Viscofan, 2019). 

The Interstate Industrial Park is situated topographically upgradient to the AASF #1 facility. Details 

of a release of PFAS containing materials could not be ascertained from public records; therefore, 

this facility is not considered an off-facility source of AFFF. 

Montgomery Air National Guard Base

The Montgomery Air National Guard Base (ANGB) is located adjacent to the Montgomery 

Regional Airport and approximately 1.25 miles northwest of the AASF #1 facility. Aircraft support 

operations at Montgomery ANGB include aircraft fueling and maintenance, aircraft deicing, fire 

protection and support, ground vehicle fueling and maintenance, and equipment and facilities 

maintenance (AECOM, 2019). 

Previous PA documentation for the Montgomery ANGB indicates that fire training was not 

performed within the facility boundary. However, an FTA was identified approximately 0.5 miles 

southeast of the Montgomery ANGB facility and across the East-West Runway on Airport property. 

According to this PA, fire training took place circa 1989 and 1991 and was conducted jointly with 

airport authority. During each exercise, an unknown quantity of spent fuel was ignited and 

extinguished using AFFF (BB&E, Inc., 2019). 

A SI was performed from December 2017 to March 2018 at the Montgomery ANGB, in areas 

deemed as potential release locations (PRLs). A total of six PRLs were investigated during the 

SI. Results of the SI indicated that PFAS were present in all media sampled at each PRL. 

Additionally, PFAS detected in base boundary wells indicate that off-base migration of PFAS is 
PFAS Preliminary Assessment Report

AASF #1 RW Shepherd, Montgomery, Alabama

17

possible (AECOM, 2019). Based on the findings of the SI report, the Montgomery Air National 

Guard Base is considered an off-facility source of PFAS.

Montgomery Regional Airport

The AASF #1 facility is located within the Montgomery Regional Airport. Multiple Aviation facilities 

are located within the Mobile Region Airport, including the Montgomery Air National Guard Base 

(ANGB) (discussed in Section 5.2). 

As noted above, an FTA was identified approximately 0.5miles southeast of the Montgomery 

ANGB facility and across the East-West Runway on Airport property and was used from 1989 to 

1991. During each exercise, an unknown quantity of spent fuel was ignited and extinguished using 

AFFF (BB&E, Inc., 2019). Additionally, some hangars at the airport are suspected to be equipped 

with AFFF suppression systems; however, the use or storage of AFFF in these hangars are 

unknown. Details of a release could not be ascertained form public records.

The AASF #1 facility is located on the southernmost and topographically upgradient portion of the 

Montgomery Regional Airport. Based on the use of an FTA on the East-West Runway, general 

airport practices and the location of AASF #1 facility within the Montgomery Regional Airport 

property, the Montgomery Regional Airport is considered an off-facility source of PFAS. 
Caney Branch

Pintlala C

er ek

Interstate

Industrial

Park

Montgomery

Regional

Airport

Montgomery Air

National Guard

Retention

Area 2

Retention

Area 1

Legend

Potential PFAS Release

No Suspected Release

Facility Boundary

Water Body

Stream/River

CLIENT

REVISED

SCALE

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12420 Milestone Center Drive

Germantown, MD 20876

Adjacent Sources

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Geographics, CNES/Airbus DS, USDA, USGS,

1:37,200

0 1,550 3,100 6,200

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18
PFAS Preliminary Assessment Report

AASF #1 RW Shepherd, Montgomery, Alabama

19

6. Preliminary Conceptual Site Model

Based on the PA findings, two AOIs were identified at the AASF #1 facility. Locations of the AOIs 

are shown on Figure 6-1. The preliminary CSM for AOI 1 is shown on Figure 6-2, and the 

preliminary CSM for AOI 2 is shown on Figure 6-3. The following sections describe the CSM 

components and the specific preliminary CSMs developed for each AOI. The CSM identifies the 

three components necessary for a potentially complete exposure pathway: (1) source, (2) 

pathway, (3) receptor. If any of these elements are missing, the pathway is considered incomplete.

Pathways

In general, the potential PFAS exposure pathways 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 (National Ground Water Association, 2018).

Known and potential AFFF releases identified at the AASF #1 facility occurred on both surface 

soil and paved surfaces. Releases to the paved surfaces could have migrated a short distance 

onto the surrounding surface soil. Ground-disturbing activities in these grassy areas as well as 

beneath the pavement may result in potential exposure to surface soils via ingestion and 

inhalation of dust particles. AFFF releases to the paved surfaces could have infiltrated the 

subsurface via cracks in the pavement or joints between areas that are paved with different 

materials. Ground-disturbing activities may result in potential exposure to subsurface soils and 

groundwater via ingestion. 

PFAS are water soluble and can migrate readily from soil to groundwater via leaching; however, 

drinking water at AASF #1 is provided by the City of Montgomery. The City of Montgomery has 

groundwater and surface water sources that contribute to 96 million gallons of water per day. 

Groundwater from City of Montgomery’s west and southwest well fields represent approximately 

one third of that capacity, while surface water from the Tallapoosa River represents approximately 

two thirds (Water Works and Sanitary Sewer Board of the city of Montgomery, 2018). The 

Tallapoosa River is located approximately 15 miles northeast of the AASF #1 facility. The west 

and southwest well fields could not be ascertained from public records. No public supply wells or 

private drinking water wells exist at the AASF #1 facility or the surrounding area within a 1-mile 

radius. It is possible that unregistered, private, domestic wells exist downgradient of the identified 

AOIs, which may result in potential exposure via ingestion of groundwater. 

Surface water runoff at the AASF #1 facility appears to drain to north and northwest. However, 

surface water may flow to the low-lying Retention Areas 1 and 2, located southeast of the flight 

ramp and southwest of the hangar building, respectively. It is possible PFAS could migrate to 

nearby tributaries, which may result in potential exposure via ingestion of surface water and 

sediment.

Receptors

Receptors at the AASF #1 facility include site workers, construction workers, off-facility 

recreational users, and off-facility residents. These receptors, as they pertain to the facility, are 

described below:

· Site workers typically work at or use the site and may come into contact with the surface soils. 

Site workers may also come into contact with surface water in the low-laying Retention Areas 

1 and 2 onsite and located southwest of the flight ramp, and southeast of the mechanical 

room, respectively. 
PFAS Preliminary Assessment Report

AASF #1 RW Shepherd, Montgomery, Alabama

20

· Construction workers are considered workers who represent a utility worker or other worker

who would be exposed to surface and/or subsurface conditions through ground-disturbing 

activities. 

· Off-facility recreational users typically identify a person who may recreationally use an offfacility area that may be affected by a PFAS release from the facility. Off-facility recreational 

users could be exposed to sediment and surface water during recreational use.

· Off-facility residents identify receptors who occupy properties outside of AASF #1. Off-facility 

residents may come into contact with groundwater using unregistered, private, domestic wells.

The preliminary CSMs for AASF #1 indicate which specific receptors could potentially be exposed 

to PFAS. The preliminary CSM for AOI 1 is shown on Figure 6-2, and the preliminary CSM for 

AOI 2 is shown on Figure 6-3.

AOI 1: Hangar Suppression System and Mechanical Room

AOI 1 encompasses the AFFF fire suppression system within the hangar building and mechanical 

room. Seepage of AFFF is evident from corrosion identified at the floor tanks in the hangar 

building. ALARNG personnel use water and mops to clean the floor within the hangar building. 

Possible releases from the floor boxes within the hangar building could be transported via 

cleaning and captured by floor drains located on the north and south ends of the hangar building. 

These floor drains empty to the oil/water separator which then discharges to the sanitary sewer. 

However, it is possible for minor amounts of AFFF to travel beyond the hangar to the flight ramp 

on the north and south ends of the building. 

Seepage of AFFF is also evident from corrosion identified at the two 800-gallon 3% AFFF 

concentrate tanks, located in the mechanical room. ALARNG personnel also noted that during 

the AFFF concentrate replacement between 2006 and 2009, an unknown quantity of concentrate 

was spilled on the south side of the mechanical room, which consequently killed the grass. Except 

for the wash rack area, surface water surrounding the hangar drains via sheet flow. The apparent 

surface water flow direction is toward the north and northwest. However, surface water may flow 

to the low-lying Retention Areas 1 and 2, located southeast of the flight ramp and southwest of 

the hangar building, respectively. 

Potential PFAS exposure pathways resulting from releases at AOI 1 are described in Table 6-1. 

Table 6-1: Exposure Pathways at AOI 1

Pathway Receptor

Surface Soil Considered a potentially complete pathway to site workers and construction 

workers via ingestion or inhalation of dust

Subsurface 

Soil

Considered a potentially complete pathway to construction workers via 

ingestion or inhalation of dust

Surface 

Water and 

Sediment

Considered a potentially complete pathway to site workers, construction 

workers, and off-facility recreational users via ingestion

Groundwater Considered a potentially complete pathway to construction workers and offfacility residents via ingestion

AOI 2: Flight Ramp and Wash Rack

AOI 2 encompasses the flight ramp located west of the hangar building. According to ALARNG 

personnel with knowledge of the facility dating back to 2000, approximately ten mobile AFFF Tri-
PFAS Preliminary Assessment Report

AASF #1 RW Shepherd, Montgomery, Alabama

21

MaxTM 30 units were staged along the flight ramp from 2001 to 2017. These units were reportedly

transported off-site and replaced with mobile Purple K units in 2017; however, there is a

discrepancy as to how the Tri-MaxTM 30 units were emptied at the AASF #1.. According to CSMS

personnel, the Tri-MaxTM units were received empty. However, information regarding how the TriMaxTM 30 units were emptied could not be ascertained by ALARNG personnel at the AASF #1

facility. Based on this discrepancy, it may be assumed that the Tri-MaxTM 30 units were discharged

on the flight ramp prior to transportation to CSMS.

ALARNG personnel also indicated that aircraft soap was used at the the wash rack area to

simulate firefighting techniques; however, it is reasonable to assume that Tri-MaxTM 30 units may

have also been used.

As described above, surface water on the flight ramp drains via sheet flow towards the north and

northwest. However, surface water could also drain to the low-lying Retention Areas 1 and 2,

located southwest of the flight ramp, and southeast of the mechanical room, respectively. There

is also one storm drain within the wash rack that empties to the oil/water separator and then the

sanitary sewer. Assuming the Tri-MaxTM 30 units were emptied on the flight ramp and wash rack,

AFFF foam would have traveled in in a manner similar to surface water flow.

Potential PFAS exposure pathways resulting from releases at AOI 2 are described in Table 6-2.

Table 6-2: Exposure Pathways at AOI 2

Pathway Receptor

Surface Soil Considered a potentially complete pathway to site workers and construction

workers via ingestion or inhalation of dust

Subsurface

Soil

Considered a potentially complete pathway to construction workers via

ingestion or inhalation of dust

Surface

Water and

Sediment

Considered a potentially complete pathway to site workers, construction

workers, and off-facility recreational users via ingestion

Groundwater Considered a potentially complete pathway to construction workers and offfacility residents via ingestion
A!

A!

A!

A!

A!

A!

Caney

Branch

Pin tlala

Creek

Interstate

Industrial

Park

Caney

Branch

Watershed

Catoma

Creek-Antioch

Branch

Watershed

Upper

Pintlala

Creek

Watershed

Middle Pintlala

Creek Watershed

Montgomery

Regional

Airport

Montgomery Air

National Guard

AOI 2

AOI 1

Legend

Area of Interest

Potential PFAS Release

No Suspected Release

Facility Boundary

Water Body

Stream/River

Surface Water Flow Direction

Inferred Groundwater Flow Direction

A! USGS Inactive Monitoring Well

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12420 Milestone Center Drive

Germantown, MD 20876

Areas of Interest

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

Geographics, CNES/Airbus DS, USDA, USGS,

1:37,200

0 1,550 3,100 6,200

Feet

Wash Rack

Mechanical

Room

Hangar

Ramp

Hazardous Waste

Storage Room

Caney

Branch

Watershed

Middle Pintlala

Creek Watershed

AOI 2

AOI 1

Retention

Area 2

Retention

Area 1

22
Media

SOURCE PATHWAY RECEPTOR

AOI 1

Hangar 

Suppression 

System Leaks 

and Mechanical 

Room Leaks

PFAS in 

Surface Soil

Human 

Activities

Leaching/

Infiltration

Precipitation

/ 

Run-Off

Airborne Soil 

Particulate

Surface Soil 

at AOI

Shallow 

Groundwater

Surface 

Water/ 

Sediment

Subsurface 

soil

Source Release 

Mechanism Media Transport and Migration Media Exposure Routes

Inhalation of 

Dust

Ingestion

Ingestion

Ingestion

Ingestion

Human Receptors: 

Current/ Future

Flow-Chart Continues

Partial / Possible Flow

Incomplete Pathway

Potentially Complete Pathway

Complete Pathway

Site 

Worker

Construction 

Worker Resident Recreational User

Site 

Worker

Construction 

Worker Resident Recreational User

LEGEND

/ / / /

/ / / /

Figure 6-2

Preliminary Conceptual Site Model

AOI 1 

Hangar Suppression System and Mechanical Room

Potential 

Off-Facility 

Source Not 

under 

Control of 

ARNG

/ /

/ / /

/

/ / /

/

Notes:

1. The resident and

recreational user 

receptors refer to an

off-site resident and

recreational user

2. Dermal contact

exposure pathway is 

incomplete for PFAS

/

/

23
Media

SOURCE PATHWAY RECEPTOR

AOI 2

Discharge of 

Trim-Max TM 30 

Units on Flight 

Ramp and Wash 

Rack

PFAS in 

Surface Soil

Human 

Activities

Leaching/

Infiltration

Precipitation

/ 

Run-Off

Airborne Soil 

Particulate

Surface Soil 

at AOI

Shallow 

Groundwater

Surface 

Water/ 

Sediment

Subsurface 

soil

Source Release 

Mechanism Media Transport and Migration Media Exposure Routes

Inhalation of 

Dust

Ingestion

Ingestion

Ingestion

Ingestion

Human Receptors: 

Current/ Future

Flow-Chart Continues

Partial / Possible Flow

Incomplete Pathway

Potentially Complete Pathway

Complete Pathway

Site 

Worker

Construction 

Worker Resident Recreational User

Site 

Worker

Construction 

Worker Resident Recreational User

LEGEND

/ / / /

/ / / /

Figure 6-3

Preliminary Conceptual Site Model

AOI 2

Flight Ramp and Wash Rack

Potential 

Off-Facility 

Source Not 

under 

Control of 

ARNG

/ /

/ / /

/

/ / /

/

Notes:

1. The resident and

recreational user 

receptors refer to an

off-site resident and

recreational user

2. Dermal contact

exposure pathway is 

incomplete for PFAS

/

/

24
PFAS Preliminary Assessment Report

AASF #1 RW Shepherd, Montgomery, Alabama

25

7. Conclusions

This report presents a summary of available information gathered during the PA on the use and 

storage of AFFF and other PFAS-related activities at the AASF #1. The PA findings are based 

on the information presented in Appendix A and Appendix B.

Findings

Two AOIs related to potential PFAS releases were identified at the AASF #1 during the PA (Figure 

7-1) and are shown in Table 7-1 below:

Table 7-1: AOIs at AASF #1

Area of Interest Name Used by Potential Release Dates

AOI 1 Hangar Fire Suppression 

System and Mechanical Room ALARNG 1995 to Present

AOI 2 Flight Ramp and Wash Rack ALARNG 2001 to 2017

Based on potential PFAS releases at these AOIs, there is potential for exposure to PFAS 

contamination in media at or near the facility. The preliminary CSM for AOI 1 and AOI 2 are shown 

on Figures 6-2 and 6-3, which presents the potential receptors and media impacted.

The following areas discussed in Section 2 through Section 5 were determined to have no 

suspected release (Table 7-2):

Table 7-2 No Suspected Release Areas

No 

Suspected 

Release 

Area

Used by Rationale for No Suspected Release Determination

Hazardous 

Waste 

Storage 

Room

ALARNG

ALARNG personnel relocated the 5-gallon concentrate jug to 

the hazardous waste storage room from the mechanical 

room. The jug was stored on a secondary containment 

pending analyses for proper disposal. During the visual 

inspection, there was no evidence of a release in the 

Hazardous Waste Storage Room.

Uncertainties

A number of information sources were investigated during this PA to determine the potential for 

PFAS-containing materials to have been present, used, or released at the facility. Historically, 

documentation of PFAS use was not required because PFAS were considered benign. Therefore, 

records were not typically kept by the facility or available during the PA on the use of PFAS in 

training, firefighting, or other non-traditional activities, or on its disposition. 

The conclusions of this PA are based on all available information, including: previous 

environmental reports, EDRsTM, observations made during the VSI, and interviews. Interviews of 

personnel with direct knowledge of a facility generally provided the most useful insights regarding 

a facility's historical and current PFAS-containing materials. Sometimes, the provided information 

was vague or conflicted with other sources. Gathered information has a degree of uncertainty due 

to the absence of written documentation, the limited number of personnel with direct knowledge 

due to staffing changes, the time passed since PFAS were first used (1969 to present), and a 
PFAS Preliminary Assessment Report

AASF #1 RW Shepherd, Montgomery, Alabama

26

reliance on personal recollection. Inaccuracies may arise in potential PFAS release locations, 

dates of release, volume of releases, and the concentration of AFFF used. There is also a 

possibility the PA has missed a source of PFAS, as the science of how PFAS may enter the 

environment continually evolves.

In order to minimize the level of uncertainty, readily available data regarding the use and storage 

of PFAS were reviewed, current personnel were interviewed, multiple persons were interviewed 

for the same potential source area, and potential source areas were visually inspected.

Table 7-3 summarizes the uncertainties associated with the PA:

Table 7-3: Uncertainties

Area of Interest Source of Uncertainty

AOI 1 The AASF #1 facility was constructed circa 1995, and ALARNG personnel 

did not have firsthand knowledge of the facility prior to 2000.

AOI 2

The AASF #1 facility was constructed circa 1995, and ALARNG personnel 

did not have firsthand knowledge of the facility prior to 2000. According to 

CSMS personnel, the Tri-MaxTM 30 units were received empty. However, 

information regarding how the Tri-MaxTM 30 units were emptied could not 

be ascertained by ALARNG personnel at the AASF #1 facility. Based on 

this discrepancy, it may be assumed that the Tri-MaxTM 30 units were 

discharged on the flight ramp prior to transportation to CSMS. ALARNG 

personnel reportedly used aircraft soap to simulate firefighting techniques 

at the wash rack. With the historical presence of Tri-MaxTM 30 units on the 

Flight Ramp, it can be assumed that these units may have also been used 

at the Wash Rack.

Potential Future Actions

Interviews with personnel whose knowledge of the facility date back to 2000 indicate that 

ALARNG activity may have resulted in potential PFAS releases at the AASF #1. Based on the 

preliminary CSMs developed for the AOIs, there is potential for receptors to be exposed to PFAS 

contamination in soil and groundwater at these AOIs. Table 7-4 summarizes the rationale used 

to determine if the AOI should be considered for further investigation under the CERCLA process 

and undergo an SI. 

Table 7-4: PA Findings Summary

Area of 

Interest AOI Location Rationale Potential Future Action

AOI 1 Hangar 

Fire 

Suppression 

System and 

Mechanical 

Room

32° 17' 8.9" 

N;86° 23' 

41.2"W

Evidence of seepage from the 

suppression system was documented 

during the visual inspection. ALARNG 

personnel also described a release of 

3% AFFF concentrate at the south side 

of the mechanical room.

Proceed to an SI, 

focus on soil, 

groundwater, 

surface water, and 

sediment.

AOI 2 Flight 

Ramp and 

Wash Rack

32° 17' 10.6" 

N; 86° 23' 

46.5 "W

Mobile Tri-MaxTM 30 units were staged 

on the flight ramp from 2001 to 2017. 

AASF #1 personnel reported that the 

Tri-MaxTM 30 units were not discharged 

on the ramp. However, CSMS 

Proceed to an SI, 

focus on soil, 

groundwater, 

surface water, and 

sediment.
PFAS Preliminary Assessment Report

AASF #1 RW Shepherd, Montgomery, Alabama

27

personnel report that the Tri-MaxTM 30

units were received at CSMS empty.

These units may have also been used

at the Wash Rack.

ARNG will evaluate the need for an SI at AASF #1 based on the potential receptors, the potential

migration of PFAS contamination off the facility, and the availability of resources.
Caney

Branch

Pin tlala

Creek

Interstate

Industrial

Park

Montgomery

Regional

Airport

Montgomery Air

National Guard

AOI 2

AOI 1

Legend

Area of Interest

Potential PFAS Release

No Suspected Release

Facility Boundary

Water Body

Stream/River

CLIENT

REVISED

SCALE

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12420 Milestone Center Drive

Germantown, MD 20876

Summary of Findings

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

Geographics, CNES/Airbus DS, USDA, USGS,

1:37,200

0 1,550 3,100 6,200

Feet

Wash Rack

Mechanical

Room

Hangar

Ramp

Hazardous Waste

Storage Room

AOI 2

AOI 1

Retention

Area 2

Retention

Area 1

28
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29

8. References

AECOM. (2019). Final Site Inspection Report, Air National Guard Phase II, Regional Site

Inspections for Per- and Polyfluoroalkyl Substances, Montgomery Air National Guard

Base, Montgomery Alabama. Joint Base Andrews: Air National Guard.

BB&E, Inc. (2016). Perfluorinated Compounds Preliminary Assessment, 187th Fighter Wing,

Montgomery Air National Guard Base, Montgomery, Alabama. Joint Base Andrews: Air

National Guard.

Economic Development Partnership of Alabama. (2019, September 9). Economic Development

Partnership of Alabama. Retrieved from Advantage Alabama:

http://advantagealabama.com/sites/283/interstate-industrial-park/interstate-65-at-ushighway-31/montgomery/montgomery-county/edpa-advantage-alabama-site-profile283.html

Genpak. (2019, November 6). Genpak. Retrieved from Genpak Food Containers:

https://www.genpak.com/

Geological Survey of Alabama. (1963). Geology and Ground-water Resources of Montgomery

County, Alabama. Tuscaloosa: Geological Survey of Alabama

Geological Survey of Alabama. 2002. Water in Alabama (Including Basic Water Data).

Tuscaloosa, Alabama: Geological Survey of Alabama.

Hyundai Power Transformers USA. (2012). About. Retrieved from Hyundai Power Transformers

USA: http://hhiamerica.com/about/sub01.htm

Montgomery County. (2019, October 15). Montgomery County, Alabama. Citizen Access Portal.

Retrieved from Montgomery County, Alabama. Citizen Access Portal: https://revco.mcala.org/

National Ground Water Association. 2018. Groundwater and PFAS: State of Knowledge and

Practice. January.

United States Environmental Protection Agency (USEPA). 1991. Guidance for Performing

Preliminary Assessments under CERCLA. September.

Viscofan. (2019, November 6). Products and Markets. Retrieved from Viscofan - The Casing

Company: http://www.viscofan.com/products-and-markets

Water Works and Sanitary Sewer Board of the city of Montgomery. (2018). 2018 Water Quality

Report. Montgomery: City of Montgomery.

WestRock. (2019, November 6). Company - Building A Paper and Packaging Leader. Retrieved

from WestRock: https://www.westrock.com/en/company#top

World Climate. (2020, January 27). Average Weather Data for Hope Hull, Alabama. Retrieved

from WorldClimate.com: http://www.worldclimate.com/climate/us/alabama/hope-hull
PFAS Preliminary Assessment Report

AASF #1 RW Shepherd, Montgomery, Alabama

Appendix A

Data Resources
PFAS Preliminary Assessment Report

AASF #1 RW Shepherd, Montgomery, Alabama

Data resources will be provided separately on CD. Data resources for AASF #1 RW Shepherd

include:

Geologic Documents

· 1963 Geology and Ground-water Resources of Montgomery County, Alabama, Geological

Survey of Alabama.

· 2002 Water in Alabama (Including Basic Water Data), Geological Survey of Alabama

Environmental Data Resources, Inc.TM Geocheck Report

· 2019 Environmental Data Resources, Inc.TM Geocheck Report for AASF #1 RW Shepherd,

Montgomery, Alabama

Miscellaneous Documents

· 2017 Final PFC Site Inspection Work Plan, Montgomery Air National Guard Base,

Montgomery, Alabama

· 2019 Final Site Inspection Report, Air National Guard Phase II, Regional Site Inspection for

Per-and Polyfluoroalkyl Substances

· 2019 Water Quality Report, Water Works and Sanitary Sewer Board of the city of

Montgomery
PFAS Preliminary Assessment Report

AASF #1 RW Shepherd, Montgomery, Alabama

Appendix B

Preliminary Assessment Documentation
PFAS Preliminary Assessment Report

AASF #1 RW Shepherd, Montgomery, Alabama

Appendix B.1

Interview Records






PFAS Preliminary Assessment Report

AASF #1 RW Shepherd, Montgomery, Alabama

Appendix B.2

Visual Site Inspection Checklists





PFAS Preliminary Assessment Report

AASF #1 RW Shepherd, Montgomery, Alabama

Appendix B.3

Conceptual Site Model Information



PFAS Preliminary Assessment Report

AASF #1 RW Shepherd, Montgomery, Alabama

Appendix C

Photographic Log
Preliminary Assessment Report

AASF #1 RW Shepherd

Perfluorooctane-Sulfonic Acid (PFOS) and 

Perfluorooctanoic Acid (PFOA) Impacted Sites

ARNG Installations, Nationwide

APPENDIX C – Photographic Log

Army National Guard, Preliminary 

Assessment for PFAS AASF #1 RW Shepherd Montgomery, Alabama

Photograph No. 1

Description:

Unknown direction

Typical AFFF foam tank on 

hangar floor

Photo date 4/10/19

Photograph No. 2

Description:

Unknown direction

Inspection tag on AFFF foam 

tank in hangar

Photo Date: 4/10/19
Preliminary Assessment Report

AASF #1 RW Shepherd

Perfluorooctane-Sulfonic Acid (PFOS) and 

Perfluorooctanoic Acid (PFOA) Impacted Sites

ARNG Installations, Nationwide

APPENDIX C – Photographic Log

Army National Guard, Preliminary 

Assessment for PFAS AASF #1 RW Shepherd Montgomery, Alabama

Photograph No. 3

Description:

Unknown direction

Corrosion from leaking AFFF 

foam tank in hangar

Photo Date: 4/10/19

Photograph No. 4

Description:

Unknown Direction

General overhead suppression 

system in hangar

Photo Date: 4/10/19
Preliminary Assessment Report

AASF #1 RW Shepherd

Perfluorooctane-Sulfonic Acid (PFOS) and 

Perfluorooctanoic Acid (PFOA) Impacted Sites

ARNG Installations, Nationwide

APPENDIX C – Photographic Log

Army National Guard, Preliminary 

Assessment for PFAS AASF #1 RW Shepherd Montgomery, Alabama

Photograph No. 5

Description:

Unknown direction

Typical floor drain in hangar. 

Floor drains located on the 

north and south sides of 

hangar building

Photo Date: 4/10/19

Photograph No. 6

Description:

Unknown direction

2 800-gallon 3% AFFF 

concentrate tanks in 

mechanical room

Photo Date: 4/10/19
Preliminary Assessment Report

AASF #1 RW Shepherd

Perfluorooctane-Sulfonic Acid (PFOS) and 

Perfluorooctanoic Acid (PFOA) Impacted Sites

ARNG Installations, Nationwide

APPENDIX C – Photographic Log

Army National Guard, Preliminary 

Assessment for PFAS AASF #1 RW Shepherd Montgomery, Alabama

Photograph No. 7

Description:

Unknown direction

Evidence of corrosion of 800-

gallon AFFF concentrate tanks 

in mechanical room

Photo Date: 4/10/19

Photograph No. 8

Description:

Unknown direction

Evidence of leaking from of 

800-gallon AFFF concentrate 

tanks in mechanical room

Photo Date: 4/10/19
Preliminary Assessment Report

AASF #1 RW Shepherd

Perfluorooctane-Sulfonic Acid (PFOS) and 

Perfluorooctanoic Acid (PFOA) Impacted Sites

ARNG Installations, Nationwide

APPENDIX C – Photographic Log

Army National Guard, Preliminary 

Assessment for PFAS AASF #1 RW Shepherd Montgomery, Alabama

Photograph No. 9

Description:

Unknown direction

Typical floor drains in 

mechanical room

Photo Date: 4/10/19

Photograph No. 10

Description:

Looking Northwest

Dead grass thought top be 

associated with AFFF release 

at south side of mechanical 

room

Photo Date: 4/10/19
Preliminary Assessment Report

AASF #1 RW Shepherd

Perfluorooctane-Sulfonic Acid (PFOS) and 

Perfluorooctanoic Acid (PFOA) Impacted Sites

ARNG Installations, Nationwide

APPENDIX C – Photographic Log

Army National Guard, Preliminary 

Assessment for PFAS RW Shepperd AASF #1 Montgomery, Alabama

Photograph No. 51

Description:

Unknown direction

5-gallon jug containing 3% 

AFFF concentrate in 

hazardous waste storage room

Photo date 4/10/19

Photograph No.12

Description:

Looking west

Mobile Purple K units on the 

flight ramp

Photo Date: 4/10/19