FINAL

Preliminary Assessment Report

AASF #3 Bates Field,

Mobile, 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

Army Aviation Support Facility #3, Mobile, Alabama

i

Table of Contents

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

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

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

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

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

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

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

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

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

1.5.3 Hydrology .......................................................................................................6

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

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

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

Wash Rack Area .....................................................................................................11

3. Non-Fire Training Areas ...................................................................................................13

Hangar Fire Suppression System ...........................................................................13

AFFF Storage Area .................................................................................................13

Flight Ramp ............................................................................................................14

4. Emergency Response Areas ............................................................................................16

5. Adjacent Sources .............................................................................................................17

United States Coast Guard .....................................................................................17

Mobile Regional Airport ...........................................................................................17

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

Pathways ................................................................................................................19

Receptors ...............................................................................................................19

AOI 1 Flight Ramp ..................................................................................................20

AOI 2 Hangar Suppression System and Washrack .................................................20

7. Conclusions .....................................................................................................................24

Findings ..................................................................................................................24

Uncertainties ...........................................................................................................24

Potential Future Actions ..........................................................................................25

8. References ......................................................................................................................28
PFAS Preliminary Assessment Report

Army Aviation Support Facility #3, Mobile, Alabama

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Tables

Table ES-1 AOIs at AASF #3 Bates Field

Table 6-1 Exposure Pathways at AOI 1 and AOI 2

Table 7-1 AOIs at AASF #3 Bates Field

Table 7-2 No Suspected Release Areas

Table 7-3 Uncertainties

Table 7-4 PA Findings Summary

Figures

Figure ES-1 Summary of Findings

Figure ES-2 Preliminary Conceptual Site Model, AASF #3 Bates Field

Figure 1-1 

Figure 1-2 

Figure 1-3 

Figure 2-1 

Figure 3-1 

Figure 5-1 

Figure 6-1 

Figure 6-2 

Figure 7-1 

Facility Location

Groundwater Features

Surface Water Features

Fire Training Area

Non-Fire Training Areas

Adjacent Sources

Areas of Interest

Preliminary Conceptual Site Model, AOI 1 Flight Ramp and AOI 2 Hangar

Suppression System and Wash Rack

Summary of Findings

Appendices

Appendix A Data Resources

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
PFAS Preliminary Assessment Report

Army Aviation Support Facility #3, Mobile, Alabama

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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

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

EDRTM Environmental Data Resources, Inc.

FTA fire training area

HA Health Advisory

MAWSS Mobile Area Water & Sewer System

NGWA National Ground Water Association

OWS oil water separator

PA Preliminary Assessment

PFAS per- and poly-fluoroalkyl substances

PFOA perfluorooctanoic acid

PFOS perfluorooctanesulfonic acid

SI Site Inspection

US United States

USACE United States Army Corps of Engineers

USCG United States Coast Guard

USEPA United States Environmental Protection Agency

USGS United States Geological Survey

VSI Visual Site Inspection
PFAS Preliminary Assessment Report

Army Aviation Support Facility #3, Mobile, Alabama

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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 the Army Aviation Support Facility (AASF) #3

Bates Field (also referred to as the “facility”), in Mobile, Alabama, to assess potential PFAS

release areas and exposure pathways to receptors. The AASF #3 facility is constructed on a

parcel of land owned by the Mobile 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 on 9 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, 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 #3 facility during the

PA. The AOIs are shown on Figure ES-1 and described in Table ES-1.

Table ES-1: AOIs at AASF #3 Bates Field

Area of Interest Name Used by Potential Release Date

AOI 1 Flight Ramp ALARNG 2002 to 2008

AOI 2

Hangar Suppression

System and Wash

Rack

ALARNG Hangar: 1999 to 2016; Wash Rack: 

2002 to 2008

Construction of the AASF #3 facility began in 1996 and was completed in 1999. The original

hangar building was equipped with an AFFF dispensing system that was replaced with 3% AFFF

from 2016 to 2018 as part of a statewide upgrade effort. Three areas were investigated during

this PA: the hangar building & AFFF suppression system, the AFFF storage building, and the flight

ramp.

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 the facility, which presents

the potential receptors and media impacted, is shown on Figure ES-2. Based on the 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.
Mobile Regional Airport

USCG 

Hangar

Hangar

Ramp

Wash Rack

AFFF Storage

AOI 1

AOI 2

Miller Creek

Pierce Creek

PierceCreek

Legend

Area of Interest

Potential PFAS Release

No Suspected Release

Facility Boundary

Water Body

Wetland

Stream/River

CLIENT

REVISED

SCALE

ARNG

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CHK BY

MS

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8/3/2020 ­ Figure ES-1 PM RG 8/3/2020

C:\Users\stankevichm\OneDrive - AECOM Directory\ARNG_PFAS_GIS_60552172\MXDs\AL\Bates_Field_AASF3\Fig_ES-1_Bates_Field_AASF3_Summary.mxd

12420 Milestone Center Drive

Germantown, MD 20876

Summary of Findings

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

Geographics, CNES/Airbus DS, USDA, USGS,

1:19,200

0 800 1,600 3,200

Feet

2
Media

SOURCE PATHWAY RECEPTOR

AOI 1

AOI 2

Hangar

Suppression

System Leaks/

Fire Training at

Wash Rack

and Discharge of

Trimax Units on

Flight Ramp

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 Transportand Migration Media ExposureRoutes

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 RecreationalUser

Site

Worker

Construction

Worker Resident Recreational

User

LEGEND

/ / / /

/ / / /

Figure ES-2

Preliminary Conceptual Site Model

AASF #3 Bates Field

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

Army Aviation Support Facility #3, Mobile, Alabama

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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 a Lifetime Health Advisory 

(HA) for PFOA and PFOS in May 2016, but there are currently no promulgated national standards 

regulating PFAS in drinking water. The HA is 70 parts per trillion for PFOS and PFOA, individually 

or combined. 

This report presents the findings of a PA for PFAS-containing materials at the current Army 

Aviation Support Facility (AASF) #3 Bates Field (also referred to as “the facility”), Mobile, 

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 9 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, 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. 
PFAS Preliminary Assessment Report

Army Aviation Support Facility #3, Mobile, Alabama

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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:

· 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 along Tanner Williams Road in Mobile County, Mobile, Alabama (Figure 1-

1) and is approximately 12 miles west of downtown Mobile.

According to ALARNG personnel, construction at the facility began in 1996 and was completed in 

1999. The facility is situated on a 66-acre parcel of land owned by the Mobile Airport Authority; 

see Appendix A for parcel details provided in the Mobile County property appraiser database. 

The current AASF #3 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 Mobile. 

Facility Environmental Setting

AASF #3 is situated in the Alluvial-Deltaic Plain district of the Coastal Plain physiographic 

province. The Alluvial-Deltaic Plain is a flat expanse characterized by sinuous stream courses, 

swamps, and poorly defined drainage divides. The facility lies in the Southern Coastal Plain 

ecoregion, which is characterized by meandering, low-gradient, and sandy bottom streams that 

flow across flat, swampy plains and bottomlands that define the local the topography. The 

surrounding landscape supports forest and woodland areas with some cropland and pasture. 

Land cover in the area is mostly longleaf-slash pine forest, oak-gum-cypress forest in some lowlying areas, pasture for beef cattle, and urban areas (US Geological Survey [USGS], 2002). 
PFAS Preliminary Assessment Report

Army Aviation Support Facility #3, Mobile, Alabama

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1.5.1 Geology

Near-surface sediments consist of undifferentiated Holocene and Pleistocene age alluvial,

coastal, and low terrace deposits characterized by white, gray, orange, and red very fine- to

coarse-grained sand with gravel and gray and orange sandy clay in some places (Geological

Survey of Alabama, 1972). Throughout most of the area, these sands are less than 50 feet thick; 

however, in the Mobile River floodplain, alluvial deposits are as much as 150 feet thick (USGS,

2019).

The Pliocene age Citronelle Formation underlies the undifferentiated Holocene and Pliocene

units. The Citronelle formation is characterized by moderate-reddish-brown, deeply weathered,

fine to very coarse quartz sand with varicolored, typically mottled, lenticular beds of clay and

clayey gravel. Limonite pebbles and lenses of limonite-cemented sand occur locally in weathered

exposures. Gravel found in the Citronelle formation is composed of chert and quartz pebbles.

(USGS, 2019).

The undifferentiated Miocene Series unconformably underlies the Citronelle Formation and is

characterized by moderate-yellowish-orange, thinly bedded to massive, fine to coarse sand,

gravelly sand, thin-bedded to massive clay, and sandy clay. Limonite pellets occur in places along

clay sand contacts. Gravel in the Miocene Series is composed of quartz and chert granules and

pebbles (USGS, 2019).

The Miocene age Pensacola Clay Formation conformably underlies the undifferentiated Miocene

Series and is characterized by greenish-gray to light olive-gray, slightly calcareous, slightly

micaceous silty to sandy clay, containing beds and lenses of sand (Geological Survey of Alabama,

1985). Geologic units are depicted on Figure 1-2.

1.5.2 Hydrogeology

The principal water-bearing sands in the Mobile County are in the undifferentiated Miocene Series

and Citronelle Formation, and these sands are referred to collectively as the Miocene Pliocene

Aquifer. Groundwater in the vicinity of the facility can be encountered at approximately 5 feet

below ground surface. Large capacity wells tapping the aquifer in Mobile County generally range

in depth from 150 to 800 feet. Prominent sands in the aquifer are not tapped by wells in many

areas because of the availability of adequate supplies at shallower depths (Geological Survey of

Alabama, 1972). Groundwater features surrounding the facility are shown in Figure 1-2, and

general groundwater flow beneath the facility is toward the southwest. According to the

Environmental Data Resources, Inc. (EDRTM) Report (Appendix A), one water well is upgradient

of the facility and identified as an inactive USGS well. According to the USGS National Water

Information System Mapper, an additional 14 inactive USGS wells have been identified within a

4-mile radius of the facility. Based on the USEPA Unregulated Contaminant Monitoring Rule 3

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

USEPA HA level 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 #3 facility lies within Mobile River Basin. Drainage at the facility consists of sheet flow

across the facility to the northwest, toward Pierce Creek and Hamilton Creek, which drain to Big

Creek Lake (Geological Survey of Alabama, 2002). Big Creek Lake, also known as Converse

Reservoir, is the main source of drinking water for almost 70 percent of Mobile County (Mobile

Area Water & Sewer System [MAWSS], 2019). Big Creek Lake is fed by springs, streams, and
PFAS Preliminary Assessment Report

Army Aviation Support Facility #3, Mobile, Alabama

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rainfall in the Converse Reservoir Watershed (MAWSS, 2018). Sewer and water services are

provided by MAWSS. 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 of about 58 degrees

Fahrenheit (°F) in northeastern Alabama to about 68 °F in southwestern Alabama. Rainfall in

Alabama usually is abundant and distributed throughout the year (Geological Survey of Alabama,

2002). The average temperature in Mobile is 67.25 °F, with an average high of 77.5 °F and an

average low of 57 °F. Mobile receives an average of 66.22 inches of rain per year

(WorldClimate.com, 2019).

1.5.5 Current and Future Land Use

The ALARNG AASF #3 facility is adjacent to the Mobile Regional Airport and a US Coast Guard

(USCG) facility located southeast of the facility. Properties surrounding the AASF #3 facility

primarily consist of commercial properties to the southeast, residential properties to the north, and

undeveloped land to the west and southwest. Reasonably anticipated future land use is not

expected to change from the current land use.
^_

Bates Field AASF #3

Legend

Facility Boundary

CLIENT

REVISED

SCALE

ARNG

GIS BY

CHK BY

MS

ST

9/4/2019

9/4/2019

NOTES Preliminary Assessment for PFAS at Bates Field AASF #3, AR

9/4/2019 ­ Figure 1-1 PM RG 9/4/2019

Q:\Projects\ENV\GEARS\GEO\ARNG PFAS\900-CAD-GIS\920-GIS or Graphics\MXD\AL\Bates_Field_AASF3\Fig_1-1_Bates_Field_AASF3_Facility_Location.mxd

12420 Milestone Center Drive

Germantown, MD 20876

Facility Location

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

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

1:126,720

0 1 2 4

Miles

8
A!

A!

A!

A!

A!

A!

A!

A!

A!

A!

A!

A!

A!

A!

A!

Twelve mile Creek

Red Creek

Crooke d Creek

Threemi le Creek

Crook ed Cree k

Milkhous e

Creek

Hamilton Creek

Stone

B ran ch

Prett y Branch

Second Creek

W olfBranc h

MillerCreek

Big Creek

Clear Creek

Doub le Branch

Pierce Creek

Hamilton Creek

Legend

Facility Boundary

Water Body

Wetland

Stream/River

Canal/Ditch

Pipeline

Inferred Groundwater Flow Direction

Geology

Alluvial, coastal, and low terrace deposits

Citronelle Formation

Miocene Series undifferentiated

Wells

A! USGS Inactive Monitoring Well

CLIENT

REVISED

SCALE

ARNG

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12420 Milestone Center Drive

Germantown, MD 20876

Groundwater Features

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

Geographics, CNES/Airbus DS, USDA, USGS,

1:95,040

0 0.75 1.5 3

Miles

9
Big Creek

Lake

Crook ed Creek

Miller Cre ek

PierceCreek

Hamilton Creek

Halls

Mill Creek

Watershed

Hamilton

Creek-Big Creek

Watershed

Miller Creek

Watershed

Pierce

Creek-Big

Creek Watershed

Legend

Facility Boundary

Water Body

Wetland

Stream/River

Canal/Ditch

Pipeline

Surface Water Flow

Direction

CLIENT

REVISED

SCALE

ARNG

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12420 Milestone Center Drive

Germantown, MD 20876

Surface Water Features

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

Geographics, CNES/Airbus DS, USDA, USGS,

1:48,000

0 2,000 4,000 8,000

Feet

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PFAS Preliminary Assessment Report

Army Aviation Support Facility #3, Mobile, Alabama

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2. Fire Training Areas

One former FTA was identified within the AASF #3 facility during the PA. A description of the FTA 

is presented below, and its location is shown on Figure 2-1. Interview Records appear in 

Appendix B, and photographs appear in Appendix C.

Wash Rack Area

According to ALARNG personnel with knowledge of the property dating back to 2002, annual fire 

training was conducted at the wash rack area located southeast of the hangar building. The 

approximate geographic coordinates for the wash rack area are 30°42’18.8”N; 88°15’5.4”W. One 

storm drain is located at the wash rack. Stormwater collected at this drain discharges to the oil 

water separator (OWS) and then the stormwater sewer. 

According to ALARNG personnel, fire training at the wash rack area was conducted with a burn 

barrel and Purple K units. As discussed in Section 3.3, approximately ten AFFF Tri-MaxTM 30 units 

were historically (until about 2008) staged along the flight ramp located southwest of the hangar 

building. Although ALARNG personal stated that only Purple K units were used in fire training, 

there is the possibility that Tri-MaxTM 30 units may have been used for fire training until about 

2008. 

Based on interviews conducted during this PA, no other fire training occurred during ALARNGs 

operation of the subject property. Based on aerial imagery dating back to 1938 and provided in 

the EDRTM report (Appendix A), features suggesting historical FTAs were not identified. 
Wash Rack

Legend

Potential PFAS Release

Facility Boundary

Water Body

CLIENT

REVISED

SCALE

ARNG

GIS BY

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12420 Milestone Center Drive

Germantown, MD 20876

Fire Training Area

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

Geographics, CNES/Airbus DS, USDA, USGS,

1:3,600

0 150 300 600

Feet

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PFAS Preliminary Assessment Report

Army Aviation Support Facility #3, Mobile, Alabama

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3. Non-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. Non-FTAs where AFFF 

was stored and/or potentially released were identified during the PA. A description of each nonFTA is presented below, and the non-FTAs are shown on Figure 3-1. Photographs of the nonFTAs are provided in Appendix C.

Hangar Fire Suppression System 

The AASF #3 hangar building contains a fire suppression system equipped with an 800-gallon 

concentrate tank filled with Chemguard 3% AFFF. Two 60,000-gallon water tanks located 

approximately 300 feet northeast of the hangar are used as the water supply for the AFFF system. 

Floor drains in the hanger building drain to the OWS and then discharge to the sanitary sewer 

system. The geographic coordinates of the hangar are 30° 42' 20.4"N; 88° 15' 7.2"W. The 

geographic coordinates of the water tanks are 30°42'22.5"N; 88°15'3.7"W. The locations of the 

hangar building and water supply tanks are depicted on Figure 3-1. The current system was 

installed from 2016 to 2018 and replaced the AFFF system that was part of the original hangar 

construction in 1999.

During the PA interviews, ALARNG personnel indicated that an unknown type of AFFF was used 

in the original suppression system. During the replacement of the original suppression system, 

the following conditions were observed by ALARNG personnel: overhead dispensing nozzles 

were rusted; the bladder system within the original AFFF concentrate tank was found to be 

ruptured, but concentrate had not traveled beyond the secondary containment; and the shutoff 

valve/backflow preventer had been installed backward. Upon discovery of the improperly installed 

shutoff valve/backflow preventer, ALARNG contracted water sampling at the facility, and drinking 

water samples were analyzed at a USEPA certified lab for PFOS and PFOA. Results of the all 

samples indicated that PFOS and PFOA compounds were not detected. The original system was 

dismantled, and the associated piping, concentrate, and concentrate tank were removed from the 

facility by a contractor, although it is unknown where the components and concentrate were taken.

Information regarding a full-scale test of the original suppression system could not be ascertained. 

According to the ALARNG personnel interviewed, a full-scale test of the new system was not 

conducted, and the system had not been triggered. During the visual inspection, corrosion and 

rust staining were observed at the floor drain beneath the current AFFF concentrate tank. 

AFFF Storage Area

During the PA site visit, ALARNG personnel noted that after the AFFF system upgrade from 2016 

to 2018, the contractor tasked with the system upgrade left two 55-gallon drums containing 

Chemguard 3% onsite. These drums contain leftover concentrate because the tank had been 

filled to capacity. ALARNG personnel currently stage these drums within a chemical storage 

building with secondary containment. At the time of the visual inspection, no evidence of drum 

leaks, rust, or spills were apparent. 

The geographic coordinates of the storage building are 30°42'18.1"N; 88°15'4.7"W. 
PFAS Preliminary Assessment Report

Army Aviation Support Facility #3, Mobile, Alabama

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Flight Ramp 

The flight ramp is located west of the hangar, and the geographic coordinates of the ramp are 

30°42' 18.1"N; 88°15'10.2"W. According to ALARNG personnel with knowledge of the facility 

dating back to 2002, approximately ten AFFF Tri-MaxTM 30 units were historically (until about 2008) 

staged along the flight ramp located southwest of the hangar building. The Tri-MaxTM 30 units were 

maintained by a contractor, and ALARNG did not have copies of the disposal documents or 

knowledge of where the Tri-MaxTM 30 units were transported and disposed of. However, ALARNG 

personnel did indicate that prior to removal of the Tri-MaxTM 30 units around 2008, these units 

were discharged southeast of the hangar building. Currently, dry chemical Purple K units are used 

on the ramp. 

It was noted during the PA that the ramp is not constructed with storm drains. Surface water 

drainage appears to flow northwest to the retention pond located at the northwest corner of the 

facility property. 
AFFF

Storage

Ramp Hangar

Legend

Potential PFAS Release

No Suspected Release

Facility Boundary

Water Body

CLIENT

REVISED

SCALE

ARNG

GIS BY

CHK BY

MS

BM

11/12/2019

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NOTES Preliminary Assessment for PFAS at Bates Field AASF #3, AL

11/12/2019 ­ Figure 3-1 PM RG 11/12/2019

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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,

1:3,600

0 150 300 600

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15
PFAS Preliminary Assessment Report

Army Aviation Support Facility #3, Mobile, Alabama

16

4. Emergency Response Areas

No emergency response areas were identified within the AASF #3 facility during the PA through

interviews of ALARNG personnel with knowledge of the property dating back to 2002 or document

review. The City of Mobile Fire Department provides fire emergency services for the AASF #3

facility, Mobile Regional Airport, and the USCG facility. AECOM requested information from the

Mobile Fire Department; however, a response was not received.
PFAS Preliminary Assessment Report

Army Aviation Support Facility #3, Mobile, Alabama

17

5. Adjacent Sources

Two potential off-facility source of PFAS adjacent to AASF #3, not under the control of the 

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

facility (located within the Mobile Regional Airport) and all other hangars, ramps, taxiways, 

runways and facilities located on the Mobile Regional Airport property not associated with 

ALARNG activity. These potential sources are depicted on Figure 5-1 and described below. 

United States Coast Guard 

A USCG facility is located within the Mobile Regional Airport property and adjacent to AASF #3, 

toward the southeast. According to ALARNG personnel interviewed, the hangar at the USCG 

facility may be equipped with an AFFF dispensing system. ALARNG personnel indicated that 

between 2014 and 2015, this suppression system was triggered and may have released AFFF. 

The geographic coordinates for this hangar are 30°41'45.8"N; 88°14'36.9"W. Details of this 

release could not be ascertained from public records. AECOM requested information from the 

Mobile Fire Department, but a response was not received.

According to ALARNG personnel, all drainage from the entire airport flows toward the AASF #3 

facility, with some surface water being captured by the detention pond located north of AASF #3. 

Based on this location and ALARNG knowledge of a possible release, this facility is considered a 

potential off-facility source of AFFF. 

Mobile Regional Airport

The AASF #3 facility is located within the Mobile Regional Airport property. According to ALARNG 

personnel, some hangars at the airport are suspected to be equipped with AFFF suppression 

systems; however, the use and storage of AFFF at the Mobile Regional Airport are unknown. 

Details of a release could not be ascertained form public records. AECOM requested information 

from the Mobile Fire Department, but a response was not received.

According to ALARNG personnel, all drainage from the entire airport flows toward the AASF #3 

facility, with some surface water being captured by the detention pond located north of the AASF. 

Based upon general airport practices, The Mobile Regional Airport is considered a potential offfacility source of PFAS to the AASF #3 facility. 
Miller Creek

Pierce Creek

PierceCreek

Mobile Regional Airport

USCG Hangar

Legend

Potential PFAS Release

Facility Boundary

Water Body

Wetland

Stream/River

CLIENT

REVISED

SCALE

ARNG

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8/3/2020 ­ Figure 5-1 PM RG 8/3/2020

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12420 Milestone Center Drive

Germantown, MD 20876

Adjacent Sources

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

Geographics, CNES/Airbus DS, USDA, USGS,

1:19,200

0 700 1,400 2,800

Feet

18
PFAS Preliminary Assessment Report

Army Aviation Support Facility #3, Mobile, Alabama

19

6. Preliminary Conceptual Site Model

Based on the PA findings, two AOIs were identified at the AASF #3 facility. The locations of the 

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

2. The following sections describe the CSM components and the specific preliminary CSM

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 Groundwater Association 

[NGWA], 2018).

AFFF releases identified at the AASF #3 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 #3 is provided by MAWSS, which resources water from Big Creek Lake, 

located approximately 3 miles northwest of the facility. Big Creek Lake is fed by springs, streams, 

and rainfall in the Converse Reservoir Watershed (MAWSS, 2018). Big Creek Lake is the main 

source of drinking water for almost 70 percent of Mobile County (MAWSS, 2019). No drinking 

water wells exist at the AASF #3 facility or the surrounding area, and one well was identified as 

an inactive USGS well on the adjacent USCG property. 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 #3 facility appears to drain to the northwest to the retention pond 

located at the northwest corner of the facility property. Drainage at the facility could also reach 

Pierce Creek and Hamilton Creek, which drain to Big Creek Lake. Big Creek Lake, also known 

as Converse Reservoir, is the main source of drinking water for almost 70 percent of Mobile 

County (MAWSS, 2019). Although laboratory analysis of the facility’s drinking water indicates 

PFAS and PFOA were not detected, it is possible PFAS could have migrated to these tributaries, 

which may result in potential exposure via ingestion of surface water and sediment.

Receptors

Receptors at the AASF #3 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 and come into contact with surface water in the retention pond. 

· 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. 
PFAS Preliminary Assessment Report

Army Aviation Support Facility #3, Mobile, Alabama

20

· Off-facility recreational users typically identify a person who has infrequent access to the site.

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 #3. Off-facility

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

The preliminary CSM for AASF #3 indicates which specific receptors could potentially be exposed 

to PFAS. The preliminary CSM for the AOIs at AASF #3 is shown on Figure 6-2. 

AOI 1 Flight Ramp 

AOI 1 encompasses the flight ramp, located west of the hangar. Releases of AFFF occurred on 

the ramp between 2002 and 2008. Historically, ten mobile Tri-MaxTM 30 units were staged along 

the ramp. ALARNG indicated the Tri-MaxTM 30 units were discharged on the ramp prior to disposal 

in 2008. 

Surface water drainage appears to flow northwest. A release of AFFF could have migrated to the 

grass areas surrounding the flight ramp, the retention pond, or tributaries feeding Big Creek Lake. 

Additionally, due to the shallow water table beneath the facility, releases of AFFF to impervious 

surfaces around the flight ramp could impact groundwater via leaching. As such, the pathways for 

PFAS exposure in AOI 1 are considered potentially complete for the site worker, construction 

worker, off-facility resident, and off-facility recreational user.

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

Table 6-1: Exposure Pathways at AOI 1 and 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 off-facility residents via ingestion

AOI 2 Hangar Suppression System and Washrack

AOI 2 encompasses the fire suppression system within the hangar building and the wash rack, 

located southeast of the hangar building. Releases of AFFF may have occurred from the fire 

suppression system sometime between 1999 and 2018. According to ALARNG personnel, 

dispensing nozzles from the previous system were rusted, which indicates corrosion from AFFF 

concentrate. If a release of AFFF from the suppression system occurred, AFFF would have 

collected in the storm drains within the hangar building. Floor drains in the hanger building drain 

to the OWS and then discharge to the sanitary sewer system. It is possible AFFF could have 

traveled outside the hangar and onto the flight ramp and migrated to surrounding grass areas. 

Releases of AFFF may have also occurred at the wash rack from around 2002 to 2008. According 

to ALARNG personnel, annual fire training was conducted with a burn barrel and Purple K units 

at the wash rack area. It is reasonable to assume that Tri-MaxTM 30 units from the flight ramp may 

have been used for fire training as well. Similar to potential releases in the hangar building, AFFF 
PFAS Preliminary Assessment Report

Army Aviation Support Facility #3, Mobile, Alabama

21

could have been collected by the storm drain located in the center of the wash rack and

discharged to the sanitary sewer system.

AFFF releases at the hangar building and wash rack not captured by storm drains could migrate

to the grass areas surrounding the flight ramp, the retention pond, or tributaries feeding Big Creek

Lake. Additionally, due to the shallow water table beneath the facility, releases of AFFF to

impervious surfaces around the flight ramp could impact groundwater via leaching. As such, the

pathways for PFAS exposure in AOI 2 are considered potentially complete for the site worker,

construction worker, off-facility resident, and off-facility recreational user. Potential PFAS

exposure pathways resulting from releases at AOI 2 are described in Table 6-1.
A!

A!

Mobile Regional Airport

Hangar

Ramp

Wash Rack

AFFF Storage

USCG

Hangar

AOI 2

AOI 1

Halls

Mill Creek

Miller Watershed

Creek

Watershed

Pierce

Creek-Big Creek

Watershed

Miller Creek

Pierce Creek

PierceCreek

Legend

Area of Interest

Potential PFAS Release

No Suspected Release

Facility Boundary

Water Body

Wetland

Stream/River

Surface Water Flow

Direction

Inferred Groundwater

Flow Direction

A! USGS Inactive

Monitoring Well

CLIENT

REVISED

SCALE

ARNG

GIS BY

CHK BY

MS

ST

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8/3/2020 ­ Figure 6-1 PM RG 8/3/2020

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12420 Milestone Center Drive

Germantown, MD 20876

Area of Interest

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

Geographics, CNES/Airbus DS, USDA, USGS,

1:19,200

0 800 1,600 3,200

Feet

22
Media

SOURCE PATHWAY RECEPTOR

AOI 1

AOI 2

Hangar

Suppression

System Leaks/

Fire Training at

Wash Rack

and Discharge of

Trimax Units on

Flight Ramp

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 Transportand Migration Media ExposureRoutes

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 RecreationalUser

Site

Worker

Construction

Worker Resident Recreational

User

LEGEND

/ / / /

/ / / /

Figure 6-2

Preliminary Conceptual Site Model

AOI 1 Flight Ramp and AOI 2 Hangar Suppression System 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

/

/

23
PFAS Preliminary Assessment Report

Army Aviation Support Facility #3, Mobile, Alabama

24

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 #3 Bates Field facility. 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 AASF #3 during the PA (Figure 7-

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

Table 7-1: AOIs at AASF #3 Bates Field

Area of Interest Name Used by Potential Release Dates

AOI 1 Flight Ramp ALARNG 2002 to 2008

AOI 2 Hangar Suppression

System and Wash Rack ALARNG Hangar: 1999 to 2016; Wash Rack: 2002 to 2008

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 AASF #3, which presents 

the potential receptors and media impacted, is shown on Figure 6-2.

The following area, which was discussed in Section 3, was 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

AFFF Storage 

Area ALARNG

After AFFF suppression system upgrades from 2016 to 2018, two 

55-gallon drums containing Chemguard 3% were left onsite.

These drums have been stored in the chemical storage building 

with secondary containment. There was no evidence of a release 

during the PA visit nor did ALARNG recall a release in this area. 

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, 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. 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 reliance on personal 

recollection. Inaccuracies may arise in potential PFAS release locations, dates of release, volume 
PFAS Preliminary Assessment Report

Army Aviation Support Facility #3, Mobile, Alabama

25

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, retired and 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 Source of Uncertainty

AOI 1: Flight Ramp and AOI 2: Hangar 

Suppression System and Wash Rack

Construction of the facility began in 1996 and 

was completed in 1999. ALARNG personnel 

did not have firsthand knowledge of the 

facility prior to 2002. Information of facility 

operation could not be ascertained for the 

time frame between 1999 to 2002. Additional 

uncertainties include the disposal of AFFF by 

the contractor maintaining the Tri-MaxTM 30 

units and disposal of AFFF from the ruptured 

AFFF concentrate tank bladder system. 

AOI 2: Hangar Suppression System and 

Wash Rack

According to ALARNG personnel, floor drains 

in the hangar and wash rack discharge to the 

OWS and then to the sanitary sewer. 

However, a drainage pipe located at the 

northeast corner of the property drains into 

the stormwater retention pond. The source of 

the drainage from the pipe is unknown. 

ALARNG has indicated that a dye tracing 

study will take place in the future to identify 

this source. 

Potential Future Actions

Interviews (of personnel with knowledge of the facility dating back to 2002) indicated that ALARNG 

activity may have resulted in potential PFAS releases at the AASF #3 Bates Field facility. Based 

on the preliminary CSM developed for the AOIs, there is potential for receptors to be exposed to 

PFAS contamination in soil, intermittent surface water and sediment, and groundwater at these 

AOIs. Table 7-4 summarizes the rationale used to determine if these AOIs should be considered 

for further investigation under the CERCLA process and undergo an SI. 

ARNG will evaluate the need for an SI at AASF #3 Bates Field based on the potential receptors, 

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

Table 7-4: PA Summary Findings

Area of 

Interest

AOI 

Location Rationale Potential Future Action

AOI 1 Flight 

Ramp

30°42'18.1"N;

88°15'10.2"W

ALARNG indicated the Tri-MaxTM 30 

units were discharged on the ramp 

prior to disposal in 2008.

Proceed to an SI, 

focus on soil, 

surface water, 

groundwater, 
PFAS Preliminary Assessment Report

Army Aviation Support Facility #3, Mobile, Alabama

26

sediment, and

surface water.

AOI 2 Hangar

Suppression

System and

Wash Rack

30°42'19.5"N;

88°15'6.3"W

During the AFFF fire suppression

system replacement from 2016 to

2018, AFFF releases occurred. Fire

training was conducted at the wash

rack with a burn barrel and Purple

K units. It is reasonable to assume

that Tri-MaxTM 30 units may have

been used for fire training until

about 2008

Proceed to an SI,

focus on soil,

surface water,

groundwater,

sediment, and

surface water.
Mobile Regional Airport

USCG 

Hangar

Hangar

Ramp

Wash Rack

AFFF Storage

AOI 1

AOI 2

Miller Creek

Pierce Creek

PierceCreek

Legend

Area of Interest

Potential PFAS Release

No Suspected Release

Facility Boundary

Water Body

Wetland

Stream/River

CLIENT

REVISED

SCALE

ARNG

GIS BY

CHK BY

MS

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8/3/2020

8/3/2020

NOTES Preliminary Assessment for PFAS at Bates Field AASF #3, AL

8/3/2020 ­ Figure 7-1 PM RG 8/3/2020

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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,

1:19,200

0 800 1,600 3,200

Feet

27
PFAS Preliminary Assessment Report

Army Aviation Support Facility #3, Mobile, Alabama

28

8. References

Geological Survey of Alabama. 1972. Water Availability in Mobile County, Alabama. University,

Alabama: Geological Survey of Alabama.

Geological Survey of Alabama. 1985. Depositional Sequences in the Pensacola Clay (Miocene)

of Southwest Alabama. Tuscaloosa, Alabama: Geological Survey of Alabama.

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

Tuscaloosa, Alabama: Geological Survey of Alabama.

Mobile Area Water and Sewer System (MAWSS). 2018. 2018 Water Quality Report: Mobile Area

Water and Sewer System

Mobile Area Water and Sewer System (MAWSS). 2019. Simple Steps You Ca Take To Protect

Our Water: Mobile Area Water and Sewer System

National Ground Water Association (NGWA). 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.

United States Geological Survey (USGS). 2002. Environmental Setting and Water-Quality

Issues of the Mobile River Basin, Alabama, Georgia, Mississippi, and Tennessee.

Montgomery, Alabama: U.S. Geological Survey.

United States Geological Survey (USGS) (2019, September 6). Geologic Units in Mobile

County, Alabama. Retrieved from USGS Mineral Resources:

https://mrdata.usgs.gov/geology/state/fips-unit.php?code=f01097

WorldClimate.com (2019, December 27). Average Weather Data for Mobile, Alabama. Retrieved

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

Army Aviation Support Facility #3, Mobile, Alabama

Data Resources
PFAS Preliminary Assessment Report

AASF #3 Bates Field, Alabama

Data resources will be provided separately on CD. Data resources for AASF #3 Bates Field

include:

Geologic Documents

• 1972 Water Availability in Mobile County, P.C. Reed and J.F. McCain, Geological Survey of

Alabama

• 1985 Depositional Sequences in the Pensacola Clay (Miocene) of Southwest Alabama,

Dorothy E. Raymond, Geological Survey of Alabama

• 2002 Water in Alabama (including basic water data), David C. Kopaska-Merkel and James

D. Moore, Geologic Survey of Alabama

• 2002 Environmental Setting and Water-Quality Issues of the Mobile River Basin, Alabama,

Georgia, Mississippi, and Tennessee, Gregory C. Johnson, Robert E. Kidd, Celeste A.

Journey, Humbert Zappia, and J. Brian Atkins, U.S. Geological Survey

Environmental Data Resources, Inc. Geocheck Report

• 2019 Environmental Data Resources, Inc. Geocheck Report for AASF #3 Bates Field,

Mobile, Alabama

Miscellaneous Documents

• 2017 Drinking Water Quality, AASF #3, State Military Department Joint Force Headquarters

Alabama Army National Guard

• 2018 Drinking Water Quality, Mobile Area Water and Sewer System

• 2019 Simple Steps You Can Take To Protect Our Waters Brochure, Mobile Area Water and

Sewer System
PFAS Preliminary Assessment Report

Army Aviation Support Facility #3, Mobile, Alabama

Preliminary Assessment Documentation
PFAS Preliminary Assessment Report

Army Aviation Support Facility #3, Mobile, Alabama

Appendix B.1

Interview Records







PFAS Preliminary Assessment Report

Army Aviation Support Facility #3, Mobile, Alabama

Appendix B.2

Visual Site Inspection Checklists








PFAS Preliminary Assessment Report

Army Aviation Support Facility #3, Mobile, Alabama

Appendix B.3

Conceptual Site Model Information



PFAS Preliminary Assessment Report

Army Aviation Support Facility #3, Mobile, Alabama

Photographic Log
Preliminary Assessment Report

AASF #3 Bates Field

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 #3 Bates Field Mobile, Alabama

Photograph No. 1

Description:

Unknown direction

General view of 800-gallon 

concentrate tank

Photo date 4/9/19

Photograph No. 2

Description:

Unknown direction

Staining below 800-gallon 

concentrate tank

Photo Date: 4/9/19
Preliminary Assessment Report

AASF #3 Bates Field

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 #3 Bates Field Mobile, Alabama

Photograph No. 3

Description:

Unknown direction

General view of overhead fire 

suppression system

Photo Date: 4/9/19

Photograph No. 4

Description:

Looking Northeast

General view 2 60,000-gallon 

water tanks supporting 

suppression system

Photo Date: 4/9/19
Preliminary Assessment Report

AASF #3 Bates Field

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 #3 Bates Field Mobile, Alabama

Photograph No. 5

Description:

Looking South

One of the 55-gallon drums 

containing 3% concentrate

Photo Date: 4/9/19

Photograph No. 6

Description:

Looking Southeast

General view of Ramp with 

mobile Purple K unit

Photo Date: 4/9/19
Preliminary Assessment Report

AASF #3 Bates Field

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 #3 Bates Field Mobile, Alabama

Photograph No. 7

Description:

Looking Northwest

General view of Ramp with 

mobile Purple K unit

Photo Date: 4/9/19

Photograph No. 8

Description:

Looking Northwest

General view of retention 

pond

Photo Date: 4/9/19
Preliminary Assessment Report

AASF #3 Bates Field

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 #3 Bates Field Mobile, Alabama

Photograph No. 9

Description:

Looking Northwest

General view of retention 

pond

Photo Date: 4/9/19

Photograph No. 10

Description:

Looking Northwest

General view of retention 

pond

Photo Date: 4/9/19