FINAL

Preliminary Assessment Report

Martindale Army Aviation Support 

Facility 

San Antonio, Texas

Perfluorooctanesulfonic Acid (PFOS) and Perfluorooctanoic 

Acid (PFOA) Impacted Sites

ARNG Installations, Nationwide

July 2020

Prepared for:

Army National Guard Bureau

111 S. George Mason Drive

Arlington, VA 22204

UNCLASSIFIED
PFAS Preliminary Assessment Report

Martindale AASF, TX

San Antonio, TX

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Table of Contents

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

1. Introduction ........................................................................................................................ 7

1.1 Authority and Purpose .............................................................................................. 7

1.2 Preliminary Assessment Methods ............................................................................. 7

1.3 Report Organization .................................................................................................. 8

1.4 Facility Location and Description............................................................................... 8

1.5 Facility Environmental Setting ................................................................................... 8

1.5.1 Geology ......................................................................................................... 9

1.5.2 Hydrogeology ................................................................................................. 9

1.5.3 Hydrology ..................................................................................................... 10

1.5.4 Climate ......................................................................................................... 10

1.5.5 Current and Future Land Use ....................................................................... 10

2. Fire Training Areas ........................................................................................................... 14

3. Non-Fire Training Areas ................................................................................................... 15

3.1 Storage and Maintenance Hangars ......................................................................... 15

3.2 Armory .................................................................................................................... 15

3.3 Fuel Station ............................................................................................................ 15

4. Emergency Response Areas ............................................................................................ 17

5. Adjacent Sources ............................................................................................................. 19

5.1 Republic Services Landfill ....................................................................................... 19

5.2 Flint Hills Resources Gas Storage Facility .............................................................. 19

5.3 AZZ Galvanizing San Antonio ................................................................................. 19

5.4 Blue Beacon Truck Wash ........................................................................................ 19

6. Preliminary Conceptual Site Model .................................................................................. 21

6.1 AOI 1 Grass Fire near Flight Line ............................................................................ 21

6.2 AOI 2 Area East of the Maintenance Hangar........................................................... 21

6.3 AOI 3 Wash Rack ................................................................................................... 22

7. Conclusions ..................................................................................................................... 27

7.1 Findings .................................................................................................................. 27

7.2 Uncertainties ........................................................................................................... 28

7.3 Potential Future Actions .......................................................................................... 28

8. References ...................................................................................................................... 31
PFAS Preliminary Assessment Report

Martindale AASF, TX

San Antonio, TX

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Figures

Figure ES-1 Summary of Findings

Figure ES-2 Preliminary Conceptual Site Model, AOI 1 AFFF Release at Flight Line at

Martindale AASF

Figure ES-3 Preliminary Conceptual Site Model, AOI 2 AFFF Release at Area East of

Maintenance Hangar at Martindale AASF

Figure ES-4 Preliminary Conceptual Site Model, AOI 3 AFFF Release at Wash Rack at

Martindale AASF

Figure 1-1 Facility Location

Figure 1-2 Groundwater Features

Figure 1-3 Surface Water Features

Figure 3-1 Non-Fire Training Areas

Figure 4-1 Emergency Response Area

Figure 5-1 Adjacent Sources

Figure 6-1 Areas of Interest

Figure 6-2 Preliminary Conceptual Site Model, AOI 1 AFFF Release at Flight Line at

Martindale AASF

Figure 6-3 Preliminary Conceptual Site Model, AOI 2 AFFF Release at Area East of

Maintenance Hangar at Martindale AASF

Figure 6-4 Preliminary Conceptual Site Model, AOI 3 AFFF Release at Wash Rack at

Martindale AASF

Figure 7-1 Summary of Findings

Tables

Table ES-1: AOIs at Martindale AASF

Table 7-1: AOIs at Martindale AASF

Table 7-2: Uncertainties

Table 7-3: Rationale

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

Martindale AASF, TX

San Antonio, TX

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Acronyms and Abbreviations

AASF Army Aviation Support Facility

AECOM AECOM Technical Services, Inc.

AFFF aqueous film forming foam

AOI area of interest

ARNG Army National Guard

CERCLA Comprehensive Environmental Response, Compensation, and Liability

Act

CSM

EDRTM

conceptual site model

Environmental Data Resources, Inc.

oF degrees Fahrenheit

FTA fire training area

IED Installations and Environment Division

HA Health Advisory

OMS Organizational Maintenance Shop

OWS oil-water separator

PA Preliminary Assessment

PFAS per- and poly-fluoroalkyl substances

PFOA perfluorooctanoic acid

PFOS perfluorooctanesulfonic acid

ppt parts per trillion

SI Site Inspection

TBWE Texas Board of Water Engineers

TXARNG Texas Army National Guard

UCMR3 Unregulated Contaminant Monitoring Rule 3

US United States

USACE United States Army Corps of Engineers

USACHPPM US Army Center for Health Promotion and Preventive Medicine

USEPA United States Environmental Protection Agency

VOC volatile organic compound

VSI visual site inspection
PFAS Preliminary Assessment Report

Martindale AASF, TX

San Antonio, TX

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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 Martindale Army Aviation Support Facility (AASF; 

also referred to as the “facility”) in San Antonio, Texas, to assess potential PFAS release areas

and exposure pathways to receptors. 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 1-day site visit on 24 April 2019 and completed visual site inspections at

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

disposed

· Interviewed personnel during the site visit who were associated with Martindale AASF

activities, including the Martindale AASF Aviation Safety Officer (on site since 2003)

· Identified areas of interest (AOIs) and developed preliminary conceptual site models (CSMs)

to outline the potential release, pathway, and receptors of PFAS for Martindale AASF

Three PFAS releases were identified during the PA, as described below. These releases

constitute three AOIs identified at Martindale AASF. The AOIs are shown in Figure ES-1 and

summarized in Table ES-1 below.

Table ES-1: AOIs at Martindale AASF

Area of

Interest Description Used by Release Dates

AOI 1 A Tri-MaxTM unit was used to fight a grass

fire adjacent to the flight line, at the

southeast end of the flight line. The

dispersed AFFF would likely collect in low

lying areas and infiltrate into the ground.

TXARNG Sometime between

1999 and 2014 (period

during which Tri-MaxTM

units were used onsite)

AOI 2 The area east of the Maintenance Hangar

includes the staging area where TriMaxTM units were stored and serviced

onsite by an outside contractor. Servicing

the units required periodic exchange of

the AFFF fluids which were then disposed

at the facility, possibly at the same area.

AFFF disposed at this area would have

migrated to the surrounding grassy areas

and eventually infiltrated into the ground.

Additionally, the fire truck was historically

located further east of the Maintenance

Hangar and is assumed to have been

equipped with AFFF tanks. AFFF

potentially leaked from the fire truck and

infiltrated into the soil below.

TXARNG Sometime between

1999 and 2014 (period

during which Tri-MaxTM

units were used

onsite). Firetruck on

site from 1980s-1990s.
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San Antonio, TX

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AOI 3 The wash rack was potentially used to

dispose of AFFF during onsite servicing of

the Tri-MaxTM units. AFFF that flowed into

the wash rack would reach the oil-water

separator (OWS), and then depending on

the position of a diverter valve, would

either travel through underground piping

to the sanitary sewer or through a series

of manholes to Rosillo Creek and then to

Salado Creek.

TXARNG Sometime between

1999 and 2014 (period

during which Tri-MaxTM

units were used onsite)

Based on the reported AFFF release at these AOIs, there is potential for exposure to PFAS

contamination in media at the facility. The preliminary CSMs for AOIs 1 through 3, which present

the potential receptors and media impacted, are shown on Figure ES-2 through ES-4. There is

currently no complete pathway for exposure to PFAS in groundwater to residents via ingestion

because all residents within a 1-mile radius of the facility are on city-supplied drinking water.

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 Health Advisories (HA) within 20 miles of the facility. 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.
Armory

Flint Hills

Resources

Grass Fire

Wash Rack

Storage Area

 for Tri-Max units 

waiting for repair

Landfill

Historic Location

of Fire Truck

AZZ Galvanizing

San Antonio

Blue Beacon

Truck Wash

Fuel Station

Storage Hangar

Maintenance Hangar

AOI 1

AOI 3

AOI 2

Rosillo Creek

0 600 1,200 2,400

Feet

Legend

Area of Interest

Potential PFAS Release

No Suspected Release

Facility Boundary

Water Body

River/Stream ­ Figure ES-1

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Media

SOURCE PATHWAY RE

AOI 1 

AFFF 

Release at Grass Fire

AFFF Release 

during Grass Fire 

near Flight Line

PFAS in 

Surface Soil 

near AOI

Human 

Activities

Precipitation/ 

Run-Off

Leaching/ Infiltration

Airborne Soil 

particulate

Surface Soil 

at AOI

Surface 

Water/ 

sediment

Subsurface 

Soil

Shallow 

Groundwater

Source Release Mechanism Media Transport and Migration Media Exposure Routes

Inhalation of 

Dust

IngestionIngestion

Ingestion

Ingestion

Hum

C

Flow-Chart ContinuesPartial / Possible FlowFlow-Chart StopsIncomplete PathwayPotentially Complete PathwayComplete Pathway

Site 

Worker

Cons

W

Site 

Worker

Cons

W

/ 

LEGEND

/ / 

Figure ES‐

Preliminary Conceptu

AOI 1 AFFF Release at Grass Fire near F

Potential 

Off-Facility 

Source Not 

under 

Control of 

ARNG

/

Note: 

1. The residential receptorrefers to an off‐facility receptor.  

/
Media

SOURCE PATHWAY RE

AOI 2 

AFFF 

Release at 

Area East of 

Maintenance 

Hangar

PFAS in 

Surface Soil 

near AOI

Human 

Activities

Precipitation/ 

Run-Off

Leaching/ Infiltration

Airborne Soil 

particulate

Surface Soil 

at AOI

Surface 

Water/ 

sediment

Subsurface 

Soil

Shallow 

Groundwater

Source Release Mechanism Media Transport and Migration Media Exposure Routes

Inhalation of 

Dust

IngestionIngestion

Ingestion

Ingestion

Hum

C

Flow-Chart ContinuesPartial / Possible FlowFlow-Chart StopsIncomplete PathwayPotentially Complete PathwayComplete Pathway

Site 

Worker

Cons

W

Site 

Worker

Cons

W

/ 

LEGEND

/ / 

Figure ES‐

Preliminary Conceptu

AOI 2 AFFF Release at Area East of Main

AASF

Potential 

Off-Facility 

Source Not 

under 

Control of 

ARNG

/

Note: 

1. The residential receptorrefers to an off‐facility receptor.  

/

Potential AFFF 

release during TriMaxTM maintenance 

events and from 

AFFF tanks on fire

truck
Media

SOURCE PATHWAY RE

AOI 3 

AFFF 

Release at 

Wash Rack

PFAS 

potentially 

leaks into 

subsurface 

soil from 

underground piping and in 

creek

Human 

Activities

Precipitation/ 

Run-Off

Leaching/ Infiltration

Airborne Soil 

particulate

Surface Soil 

at AOI

Surface 

Water/ 

sediment

Subsurface 

Soil

Shallow 

Groundwater

Source Release Mechanism Media Transport and Migration Media Exposure Routes

Inhalation of 

Dust

IngestionIngestion

Ingestion

Ingestion

Hum

C

Flow-Chart ContinuesPartial / Possible FlowFlow-Chart StopsIncomplete PathwayPotentially Complete PathwayComplete Pathway

Site 

Worker

Cons

W

Site 

Worker

Cons

W

/ 

LEGEND

/ / 

Figure E

Preliminary Concep

AOI 3 AFFF Release at Wash 

Potential 

Off-Facility 

Source Not 

under 

Control of 

ARNG

/

Note: 

1. The residential receptorrefers to an off‐facility receptor.  

/

AFFF release 

during Tri-MaxTM 

maintenance events 

at wash rack

PFAS travels 

to OWS and 

then through 

underground 

piping either 

to sanitary 

sewer or to 

Rosillo 

Creek
PFAS Preliminary Assessment Report

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San Antonio, TX

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1. Introduction

1.1 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 their facilities

that used per- and poly-fluoroalkyl substances (PFAS), primarily releases of aqueous film forming

foam (AFFF), although other sources of PFAS 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. The regulatory

framework at both federal and state levels continues to evolve. The US Environmental Protection

Agency (USEPA) issued a drinking water lifetime Health Advisory (HA) for PFOA and PFOS in

May 2016, but there are currently no promulgated national standards regulating PFAS in drinking

water.

This report presents findings of a PA for PFAS-containing materials at Martindale Army Aviation

Support Facility (AASF; also referred to as the “facility”) in San Antonio, Texas, 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 Part 300), and Army requirements and guidance.

This PA documents the locations where PFAS were historically stored and reportedly released

into the environment at Martindale AASF. 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.

1.2 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 1-day site visit on 24 April 2019 and completed visual site inspections (VSIs)

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

disposed

· Interviewed personnel during the site visit who were associated with Martindale AASF

activities, including the Martindale AASF Aviation Safety Officer (on site since 2003)

· Identified areas of interest (AOIs) and developed preliminary conceptual site models (CSMs)

to outline the potential release, pathway, and receptors of PFAS for Martindale AASF
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Martindale AASF, TX

San Antonio, TX

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1.3 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 potential or suspected fire training areas

(FTAs) at the facility identified during the site visit

· Section 3 – Non-Fire Training Areas: describes other locations of potential or suspected

PFAS releases at the facility identified during the site visit

· Section 4 – Emergency Response Areas: describes areas of suspected or potential AFFF

release at the facility, specifically in response to emergency situations

· Section 5 – Adjacent Sources: describes sources of 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 at the areas of interest (AOIs)

· 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

1.4 Facility Location and Description

Martindale AASF is located within the San Antonio city limits, southeast of the intersection of

Interstate 10 and Interstate 410. The facility is located 7 miles east of downtown San Antonio

(Figure 1-1). The facility comprises approximately 220 acres of mostly grassland, as well as a

storage hangar, maintenance hangar, armory, and flight lines (US Army Center for Health

Promotion and Preventive Medicine [USACHPPM], January 1997). The facility was opened by

the US Air Force in 1943 for the purpose of training and was restricted to take offs and landings.

The property deed was transferred from the Air Force to the ARNG in 1954. Most of the buildings

were constructed in the early 1960’s except for the current Organizational Maintenance Shop

(OMS) built in 1991, the Storage Hangar built in 2004, and additional facility support buildings

built from 2010 to 2012.

1.5 Facility Environmental Setting

Martindale AASF is located in Bexar County, south-central Texas, approximately 140 miles

northwest of the Gulf of Mexico. The facility is about 10 miles northwest of Calaveras Lake and

less than 1 mile west of Rosillo Creek. The 220-acre facility is located within the San Antonio city

limits, east of the city center. Industrial/commercial properties lie to the north, with Interstate 10

beyond. West and southwest of the facility are predominately single-family homes, with Interstate

410 beyond. East and southeast of the facility are agricultural/undeveloped properties with Rosillo

Creek beyond. South of facility are industrial/undeveloped properties, with E. Houston Street
PFAS Preliminary Assessment Report

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San Antonio, TX

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beyond. As described in Section 5, some nearby industrial facilities represent potential PFAS

sources.

1.5.1 Geology

The facility is underlain by fluviatile terrace deposits of the Quaternary period consisting of gravel,

sand, silt and clay. The fluviatile terrace deposits are underlain by the Midway Group consisting

of clay and sand deposited in the Tertiary period (Figure 1-2) (USACHPPM, January 1997). The

Edwards Limestone outcrops about 10 miles to the north-northwest of the facility, on the upward

shifted side of significant northeast – southwest trending normal faults (Bureau of Economic

Geology, 1982). The facility lies on the downward-shifted side of this fault zone and therefore has

several hundred feet of younger Quaternary, Tertiary and Upper Cretaceous geologic units

overlying the Edwards Limestone (Texas Board of Water Engineers [TBWE], 1959).

1.5.2 Hydrogeology

The Edwards Limestone is the sole-source aquifer for the San Antonio area, and San Antonio

obtains its entire water supply from this aquifer. The presence of a fault zone coupled with the

high degree of fracturing in the limestone results in a complex flow pattern. The top of the Edwards

aquifer is bounded by an upper confining layer, resulting in artesian conditions. The nearest water

supply well is approximately 1.5 miles north of the facility. The well is reported as 1,139 feet deep

and supplies the City of Kirby. Shallower water-bearing zones are most likely discontinuous

perched lenses and not used as a drinking water supply in the San Antonio area (USACHPPM,

January 1997). Shallow unconfined groundwater would normally follow the local topography,

which is to the southeast, towards Rosillo Creek.

No wells exist at the facility. An exploratory boring was drilled on 8 July 1988 to provide information

to bidders on a contract to construct the OMS building. The borehole extended to a depth of 20.5

feet, and it remained open for at least 3 days, at which time the groundwater level was measured

at 15.8 feet below the ground surface. There are no data available on the behavior of this

uppermost water-bearing zone at the facility. The shallow water is not used as a drinking water

supply in the San Antonio area and is probably a discontinuous perched lens with little or no

interconnection with the Edwards aquifer (USACHPPM, January 1997). The direction of

groundwater flow at the facility has not been determined because of the lack of static water level

data collected from area wells. However, the general groundwater flow in the Edwards aquifer in

San Antonio is to the southeast (TBWE, August 1954).

A query of the Texas Water Development Board’s Interactive Groundwater Data Viewer identified

71 monitoring wells and 92 environmental soil boring records within a 1-mile radius of the center

of the facility (Figure 1-2). The monitoring wells directly north of the facility are owned by Travel

Centers of America, and NuStar Logistics, LP owns 13 monitoring wells approximately 0.8 miles

northeast of the facility. Midtex Oil, LP and CCC Group own 18 monitoring wells approximately

0.8 miles north-northeast of the facility. Other monitoring wells located within a 1-mile radius of

the facility are owned by LIT Industrial Texas, LP, Southwest Galvanizing, Summit Truck Group,

and York International Corp., among others.

The facility’s drinking water is supplied by the City of San Antonio. 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 HA within 20 miles of the facility. 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.
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1.5.3 Hydrology

Surface water at the facility flows through ditches around the perimeter of the flight line to the

southeast and settles in a retention pond (Figure 1-3). The retention pond in the southeast corner

of the facility is less than 2,000 feet from Rosillo Creek, so it is likely that surface water flows from

the retention pond to the creek under heavy rain conditions.

Wastewater that collects in the wash rack flows to an oil-water separator (OWS) and then,

depending on the position of a diverter valve, either travels through underground piping to the

sanitary sewer, or goes through a series of manholes and then discharges to Rosillo Creek and

then Salado Creek.

1.5.4 Climate

The San Antonio climate is humid subtropical, with long, hot summers and warm to cool winters.

Cold fronts from the north occasionally descend during the winters and affect the weather

conditions. Summers are hot, with the average high temperature around 99 degrees Fahrenheit

(°F) in the peak of August (National Weather Service Forecast Office, 2019). Winters range from

mild to cool, with the average daily highs rarely dropping below 60°F. The spring and autumn

months tend to be warm and wet. The average humidity in San Antonio is around 67%. San

Antonio is usually sunny, with average annual precipitation around 32 inches. May, June, and

October tend to be the rainiest months. Snowfall is rare in San Antonio, but the area experiences

sleet and freezing rain on a few occasions. Floods occur regularly, and tornados occur

occasionally in the region (Weather Atlas, 2019).

1.5.5 Current and Future Land Use

The Martindale AASF currently includes temporary and permanent storage buildings, an OMS

building, two hangars, and an armory used for administration. Current land use in the direct vicinity

of the facility includes undeveloped/agricultural land to the east, residential land to the west, and

commercial/industrial land to the north and south. Historically, undeveloped land surrounding the

facility was leased to a farmer who grew corn until 2 or 3 years ago (2016/2017). No future

changes to the current use were noted during personnel interviews.
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Facility Location

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

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Facility Boundary

0 0.5 1 2

Miles

^_

Martindale

11
A!

A!

AA!!

A!A!

A!

A!!A!

A

!

A!

AA!

A!

A!A!A!A! A!

A!

A!A!

A! A! A! A! A! A!A! A!A!

A!

A!

A!

A!

A! A!

A!A!A!

A!

Rosillo Creek

Ackerman

Creek

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Groundwater Features

Base Map: Source: Esri, DigitalGlobe, GeoEye,

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

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Legend

Facility Boundary

Water Body

River/Stream

Canal/Ditch

Inferred Groundwater

Flow Direction

Geology

Fluviatile Terrace

Deposits

Wilcox Group

Midway Group

Navarro Group and

Marlbrook Marl

Wells

A! Monitoring Well

0 0.25 0.5 1

Miles

12
Rosillo

Creek

Watershed

Rosillo Creek

Ackerman

Creek

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12420 Milestone Center Drive

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Surface Water Features

Base Map: Source: Esri, DigitalGlobe, GeoEye,

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

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Legend

Facility Boundary

Water Body

River/Stream

Canal/Ditch

Surface Water Flow

Direction

13
PFAS Preliminary Assessment Report

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2. Fire Training Areas

Martindale AASF personnel confirmed there are no designated FTAs at the facility. There were no

reports of mobile cart extinguisher testing/training anywhere at the facility, except for a report

regarding training with one Tri-MaxTM unit that was full of water, not AFFF. Information was

obtained from personnel who had worked at the facility since 2002; however, the Tri-MaxTM units

had been at the facility since approximately 1999.
PFAS Preliminary Assessment Report

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San Antonio, TX

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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. The Martindale AASF

comprises a flight line, several buildings (two hangars, an armory, administrative buildings, and

storage), and a wash rack area. These non-FTAs were investigated during the PA. These and

other areas are described below and shown on Figure 3-1, with photographs provided in

Appendix C.

3.1 Storage and Maintenance Hangars

There are two hangars at the Martindale AASF: a Storage Hangar located in the northwest section

of the facility and the Maintenance Hangar located east of the Storage Hangar. The hangars are

used for helicopter maintenance, storage, and training. The area directly east of the Maintenance

Hangar is where Tri-MaxTM units were kept when they were waiting to be repaired/serviced.

Interviews indicated that the Tri-MaxTM units were serviced onsite by an outside contractor. This

process required periodic exchange of the AFFF fluids which were disposed at the facility, possibly

at this area or at the wash rack. Further east of the Maintenance Hangar is the location where the

fire truck was stationed when it was on site. Although interviewees were unsure, the fire truck is

assumed to have contained AFFF tanks and capability. Interviews indicated that the fire truck was

never used. Martindale AASF staff report that the Tri-MaxTM units were never discharged (except

for an emergency response at the grass fire discussed in Section 4), and that the Tri-MaxTM tanks

were removed from the facility and hydrostatically tested at a contractor’s facility off-site. TXARNG

staff report that both hangars are not equipped with fire suppression systems. The geographic

coordinates for the Storage Hangar are 29°26'06.52"N; 98°22'56.06"W, and the geographic

coordinates for the Maintenance Hangar are 29°26'06.97"N; 98°22'51.49"W.

3.2 Armory

The armory is located to the east of the two hangars. The armory is used for mainly administrative

purposes and contains an assembly hall and a kitchen. The kitchen was checked for the use of

AFFF, and none was found. The kitchen uses K Class fire extinguishers, which do not contain

AFFF. No TXARNG staff reported historic or current use of AFFF in the armory building. The

geographic coordinates for the AASF hangar are 29°26'06.28"N; 98°22'45.32"W.

3.3 Fuel Station

Historically, one AFFF-containing Tri-MaxTM unit was stationed near the Fuel Station at the facility.

TXARNG staff who had been working at the facility since 2002 reported no releases of any

materials in this area. Geographic coordinates for the fuel station are 29°26'04.24"N;

98°22'49.74"W.
Wash Rack

Storage Area

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Historic Location 

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Fuel Station

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Storage Hangar

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4. Emergency Response Areas

During personnel interviews, it was revealed that Tri-MaxTM units were used to fight a grass fire

on the flight line. The date of the incident is unknown, but it happened sometime between 1999

and 2014, when Tri-MaxTM units were present at the facility. The approximate location of the grass

fire is shown on Figure 4-1. Three or four Tri-MaxTM units were historically located along the flight

line for firefighting purposes. The City of San Antonio fire department came out to fight the grass

fire as well and used water (not AFFF) to put out the remaining fire.

To the best of their knowledge, TXARNG personnel who have been working at the facility since

2002 reported no other past emergency responses. Between 1954 and 2002, it is unknown if

other emergency response actions occurred.
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5. Adjacent Sources

Adjacent sources of potential PFAS include the Republic Services Landfill, the Flint Hills

Resources gas storage facility, AZZ Galvanizing San Antonio, and Blue Beacon Truck Wash.

Figure 5-1 shows the various adjacent sources described in this section. The groundwater flow

direction at the facility is inferred to be to the southeast, as this is the regional groundwater flow

direction in the San Antonio area. Both the Flint Hills Resources gas storage facility and the landfill

are cross-gradient from the AASF, with the Flint Hills Resources gas storage facility located to the

southwest, and the landfill located to the east of the facility. Blue Beacon Truck Wash is upgradient

of the facility, and AZZ Galvanizing is downgradient of the facility.

5.1 Republic Services Landfill

The Republic Services Landfill is located about two miles east of the facility. This landfill could be

a potential source of PFAS. Landfills are not usually a primary release area of PFAS, but materials

disposed in landfills may create a secondary source of contamination. Such materials may include

sludge from a wastewater treatment plant that processes PFAS-laden water, used AFFF storage

containers, or products associated with waterproofing such as uniforms or boots.

5.2 Flint Hills Resources Gas Storage Facility

Flint Hills Resources gas storage facility is located approximately 5,000 feet southwest of the

Martindale AASF. A gas storage facility may have and use AFFF on-site because of the need to

have effective firefighting capabilities at facilities with large quantities of bulk fuel.

5.3 AZZ Galvanizing San Antonio

AZZ Galvanizing is located at 5731 FM 1346 in San Antonio, approximately 1,040 feet southsoutheast of the facility. AZZ Galvanizing is a large quantity generator as defined by USEPA,

meaning that it generates over 1,000 kilograms of hazardous waste, or over 1 kilogram of acutely

hazardous waste per month. A hazardous waste summary for the site describes it as having

ignitable waste, corrosive waste, arsenic, cadmium, chromium, lead, and selenium waste. The

processes conducted at AZZ Galvanizing are described as metal coating and allied services. The

process of metal plating and etching is known to use PFAS for corrosion prevention, mechanical

wear reduction, aesthetic enhancement, surfactant, wetting agent/fume suppressant for chrome,

copper, nickel and tin electroplating, and post-plating cleaner (Interstate Technology Regulatory

Council, 2017). It is possible that the processes conducted at AZZ Galvanizing include the use of

PFAS. More information on AZZ Galvanizing can be found in the Environmental Data Resources,

Inc. (EDR)TM Radius Map Report located in Appendix A.

5.4 Blue Beacon Truck Wash

Blue Beacon Truck Wash of San Antonio is located at 1112 Ackerman Road in San Antonio,

directly north of the facility. The truck wash shares the northern boundary of the facility. A chemical

inventory of the site indicated that hydrogen fluoride in an average daily amount of 1,000 to 9,999

pounds was used at the site in 2010. Although the processes that occur at the truck wash are

unknown, it is possible that PFAS are used in the buffing and water-proofing process at the truck

wash. PFAS use has been linked to car wash facilities in various locations around the US. Of note

is a 38,500 square foot retention pond, located to the east of the truck wash, that appears (from

aerial imagery) to receive the wastewater from the truck wash activities. More information on Blue

Beacon Truck Wash of San Antonio can be found in the EDRTM Radius Map Report located in

Appendix A.
C alaverasC

er ek

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Ackerm an Creek

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Resources

Landfill

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Blue Beacon

Truck Wash

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Facility Boundary

Water Body

River/Stream

Canal/Ditch

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PFAS Preliminary Assessment Report

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6. Preliminary Conceptual Site Model

Based on the PA findings, three AFFF release areas were identified. The AFFF release area

associated with the Martindale AASF grass fire at the flight line was identified as AOI 1. The AFFF

release area associated with the area east of the Maintenance Hangar as well as the location of

the historic fire truck (located further east of the Maintenance Hangar) were identified as AOI 2,

and the wash rack was identified as AOI 3. This section describes the preliminary CSM

components developed for these AOIs. The CSM identifies the three components necessary for

a potentially complete exposure pathway: (1) source, (2) pathway, and (3) receptor. If any of these

elements are missing, the pathway is considered incomplete. The AOIs are shown on Figure 6-

1, and the preliminary CSMs for AOI 1 through AOI 3 are presented on Figure 6-2 through Figure

6-4.

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 is sparse and 

continues to be the subject of PFAS toxicological study. Receptors at Martindale AASF include

site workers and construction workers. As described below, the preliminary CSMs for the AOIs

detail the specific receptors that could potentially be exposed to PFAS.

6.1 AOI 1 Grass Fire near Flight Line

AFFF was used to put out a grass fire near the southwest end of the flight line during one event

that took place between 1999 and 2014. An unknown quantity of AFFF was released during this

emergency firefighting response.

Releases at the grassy areas on either side of the flight line would eventually infiltrate into the soil

and potentially infiltrate to the subsurface and groundwater via rainwater infiltration. Under such

scenarios, ground disturbing activities in these areas could result in site or construction worker

exposure to PFAS via inhalation of dust or ingestion of exposed soil. PFAS contamination may

have further infiltrated to shallow groundwater; however, there are no groundwater receptors 

identified within a 1-mile radius of the facility, so the groundwater exposure pathway is incomplete.

PFAS may have accumulated in nearby storm water ditches, located both north and south of the

flight line, creating an exposure pathway to site workers, construction workers, and trespassers

from surface water/sediment in this area.

6.2 AOI 2 Area East of the Maintenance Hangar

AFFF was potentially released at the area east of the Maintenance Hangar during Tri-MaxTM

maintenance events performed by an outside contractor. The AFFF fluids stored in the Tri-MaxTM

units were disposed during these maintenance events. Additionally, the fire truck, which was

historically stored further east of the Maintenance Hangar, likely contained AFFF tanks, and AFFF

could have leaked on to the gravel surface beneath the truck.

Releases at the area east of the Maintenance Hangar may have infiltrated into surrounding grassy

areas when washed off the concrete surface, and potential releases at the fire truck may have

infiltrated into the gravel and soil beneath it. Releases in either area have the potential to infiltrate

into soil and further into the subsurface via rainwater infiltration. Under such scenarios, ground

disturbing activities in these areas could result in site or construction worker exposure to PFAS

via inhalation of dust or ingestion of exposed soil. PFAS contamination may have further infiltrated

to shallow groundwater; however, there are no groundwater receptors identified within a 1-mile

radius of the facility, so the groundwater exposure pathway is incomplete.
PFAS Preliminary Assessment Report

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6.3 AOI 3 Wash Rack

AFFF was potentially released at the wash rack during Tri-MaxTM maintenance events performed

by an outside contractor. The AFFF fluids stored in the Tri-MaxTM units would have been disposed

during these maintenance events.

Releases at the wash rack would have traveled to the OWS and then, depending on the position

of a diverter valve, either traveled through underground piping to the sanitary sewer, or traveled

through a series of manholes and then discharged to Rosillo Creek and then to Salado Creek.

Releases at the wash rack have the potential to infiltrate into soil and further into the subsurface

via leaks in underground piping. Under such scenarios, ground disturbing activities in this area

could result in site or construction worker exposure to PFAS via inhalation of dust or ingestion of

exposed soil. PFAS contamination may have further infiltrated to shallow groundwater; however, 

there are no groundwater receptors identified within a 1-mile radius of the facility, so the

groundwater exposure pathway is incomplete.
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AOI 1

AOI 3

AOI 2

Flint Hills

Resources

Grass Fire

Wash Rack

Storage Area for

Tri-Max units waiting for repair

Landfill Historic Location

of Fire Truck

AZZ Galvanizing

San Antonio

Blue Beacon

Truck Wash

Fuel Station

Storage Hangar Armory

Maintenance Hangar

Rosillo Creek

Rosillo Creek

Watershed

Upper Calaveras

Creek Watershed

Salitrillo

Creek-Martinez

Creek Watershed

0 600 1,200 2,400

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Legend

Area of Interest

Potential PFAS Release

No Suspected Release

Facility Boundary

Water Body

River/Stream

Surface Water Flow Direction

Inferred Groundwater Flow Direction

A! Monitoring Well

­ Figure 6-1

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23
Media

SOURCE PATHWAY RE

AOI 1 

AFFF 

Release at Grass Fire

AFFF Release 

during Grass Fire 

near Flight Line

PFAS in 

Surface Soil 

near AOI

Human 

Activities

Precipitation/ 

Run-Off

Leaching/ Infiltration

Airborne Soil 

particulate

Surface Soil 

at AOI

Surface 

Water/ 

sediment

Subsurface 

Soil

Shallow 

Groundwater

Source Release Mechanism Media Transport and Migration Media Exposure Routes

Inhalation of 

Dust

IngestionIngestion

Ingestion

Ingestion

Hum

C

Flow-Chart ContinuesPartial / Possible FlowFlow-Chart StopsIncomplete PathwayPotentially Complete PathwayComplete Pathway

Site 

Worker

Cons

W

Site 

Worker

Cons

W

/ 

LEGEND

/ / 

Figure 6‐2

Preliminary Conceptua

AOI 1 AFFF Release at Grass Fire near Fl

Potential 

Off-Facility 

Source Not 

under 

Control of 

ARNG

/

Note: 

1. The residential receptorrefers to an off‐facility receptor.  

/
Media

SOURCE PATHWAY RE

AOI 2 

AFFF 

Release at 

Area East of 

Maintenance 

Hangar

PFAS in 

Surface Soil 

near AOI

Human 

Activities

Precipitation/ 

Run-Off

Leaching/ Infiltration

Airborne Soil 

particulate

Surface Soil 

at AOI

Surface 

Water/ 

sediment

Subsurface 

Soil

Shallow 

Groundwater

Source Release Mechanism Media Transport and Migration Media Exposure Routes

Inhalation of 

Dust

IngestionIngestion

Ingestion

Ingestion

Hum

C

Flow-Chart ContinuesPartial / Possible FlowFlow-Chart StopsIncomplete PathwayPotentially Complete PathwayComplete Pathway

Site 

Worker

Cons

W

Site 

Worker

Cons

W

/ 

LEGEND

/ / 

Figure 6‐3

Preliminary Conceptu

AOI 2 AFFF Release at Area East of Main

AASF

Potential 

Off-Facility 

Source Not 

under 

Control of 

ARNG

/

Note: 

1. The residential receptorrefers to an off‐facility receptor.  

/

Potential AFFF 

release during TriMaxTM maintenance 

events and from 

AFFF tanks on fire

truck
Media

SOURCE PATHWAY RE

AOI 3 

AFFF 

Release at 

Wash Rack

PFAS 

potentially 

leaks into 

subsurface 

soil from 

underground piping and in 

creek

Human 

Activities

Precipitation/ 

Run-Off

Leaching/ Infiltration

Airborne Soil 

particulate

Surface Soil 

at AOI

Surface 

Water/ 

sediment

Subsurface 

Soil

Shallow 

Groundwater

Source Release Mechanism Media Transport and Migration Media Exposure Routes

Inhalation of 

Dust

IngestionIngestion

Ingestion

Ingestion

Hum

C

Flow-Chart ContinuesPartial / Possible FlowFlow-Chart StopsIncomplete PathwayPotentially Complete PathwayComplete Pathway

Site 

Worker

Cons

W

Site 

Worker

Cons

W

/ 

LEGEND

/ / 

Figure 6

Preliminary Concept

AOI 3 AFFF Release at Wash R

Potential 

Off-Facility 

Source Not 

under 

Control of 

ARNG

/

Note: 

1. The residential receptorrefers to an off‐facility receptor.  

/

AFFF release 

during Tri-MaxTM 

maintenance events 

at wash rack

PFAS travels 

to OWS and 

then through 

underground 

piping either 

to sanitary 

sewer or to 

Rosillo 

Creek
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7. Conclusions

Three AOIs were identified at Martindale AASF during the PA (Figure 7-1).

7.1 Findings

Based on interviews with current AASF personnel, Tri-MaxTM units were serviced onsite by an

outside contractor and required periodic exchange of the AFFF fluids. These fluids would have

been disposed at the facility, either at the area east of the Maintenance Hangar, or at the wash

rack. Additionally, a fire truck was stationed further east of the Maintenance Hangar and could

have leaked AFFF over the years. Finally, a reported historical AFFF release was associated with

the grass fire located near the southeast end of the flight line. These releases indicate the potential

for PFAS contamination in surface and subsurface soil to intercept one or more receptors.

Groundwater in the area is not used for drinking water. However, PFAS contamination may have

accumulated in surface water and sediments in the drainage ditches located near the grass fire,

in the grassy areas surrounding the Maintenance Hangar, or in the subsurface beneath the wash

rack. No evidence of other accidental or incidental spills or leaks from AFFF storage

containers/areas were identified during the site visit. The remaining buildings associated with the

AASF are not equipped with or store AFFF. The findings of potential AFFF release are

summarized in Table 7-1 below.

Table 7-1: AOIs at Martindale AASF

Area of

Interest

Description Used by Release Dates

AOI 1 A Tri-MaxTM unit was used to fight a grass fire

adjacent to the flight line, at the southeast end

of the flight line. The dispersed AFFF would

likely collect in low lying areas and infiltrate

into the ground.

TXARNG Sometime between

1999 and 2014

(period during which

Tri-MaxTM units were

used onsite)

AOI 2 The area east of the Maintenance Hangar

includes the staging area where Tri-MaxTM

units were stored and serviced onsite by an

outside contractor. Servicing the units

required periodic exchange of the AFFF fluids

which were then disposed at the facility,

possibly at the same area. AFFF disposed at

this area would have migrated to the

surrounding grassy areas and eventually

infiltrated into the ground. Additionally, the fire

truck was historically located further east of

the Maintenance Hangar and is assumed to

have been equipped with AFFF tanks. AFFF

potentially leaked from the fire truck and

infiltrated into the soil below.

TXARNG Sometime between

1999 and 2014

(period during which

Tri-MaxTM units were

used onsite). The

firetruck was onsite

from the 1980s to

1990s.

AOI 3 The wash rack was potentially used to

dispose of AFFF during onsite servicing of the

Tri-MaxTM units. AFFF that flowed into the

wash rack would reach the OWS, and then

depending on the position of a diverter valve,

either travel through underground piping to

the sanitary sewer or through a series of

TXARNG Sometime between

1999 and 2014

(period during which

Tri-MaxTM units were

used onsite)
PFAS Preliminary Assessment Report

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manholes to Rosillo Creek and then to Salado

Creek.

7.2 Uncertainties

Available 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 disposal.

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 incomplete. 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

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 7-2 summarizes the uncertainties associated with the PA:

Table 7-2: Uncertainties

Area of Interest Source of Uncertainty

AOI 1 The extent of the grass fire is unknown, as well as the quantity of

AFFF deployed to fight the fire.

AOI 2 The location where the disposal of AFFF from Tri-MaxTM units

occurred is unknown. It is assumed that AFFF was disposed

either at the area east of the Maintenance Hangar or at the wash

rack. In addition, the position of the diverter valve at the OWS is

unknown.

AOI 3 It would be unusual to have a fire truck at the facility that did not

contain AFFF tanks and capability during the 1980s-1990s. Since

the interviewees were unsure, we have assumed that the fire

truck had AFFF capability.

Historic AFFF Use Information from 1954 (when TXARNG acquired the facility) to

2002 (when interviewee started work at the facility) is not

available. AFFF use during this time period is not known.

7.3 Potential Future Actions

Based on the documented absence (2002-present) of the release of PFAS-containing materials

at the AASF Hangars and Armory, evidence does not indicate that current or former TXARNG

activities in these areas contributed PFAS contamination to soil, groundwater, surface water, or
PFAS Preliminary Assessment Report

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sediment at Martindale AASF. The AASF Hangars and Armory will not move forward in the

CERCLA process.

Interviews (covering 2002 to present) indicate that a release of AFFF during grass firefighting

occurred near the southeast end of the flight line (AOI 1) and resulted in PFAS release. Based on

the preliminary CSM developed for the AOI, there is potential for receptors to be exposed to PFAS

contamination in soil and surface water/sediment at AOI 1. Additionally, AFFF may have been

released at both the area east of the Maintenance Hangar as well as the historic location of the

fire truck (AOI 2) and at the wash rack (AOI 3). Table 7-3 summarizes the rationale used to

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

and undergo an SI.

ARNG will evaluate the need for an SI at Martindale AASF based on the presence of a PFAS

release, possible receptors, the migration potential of PFAS contamination to receptors, and the

availability of resources.

Table 7-3: Rationale

Area of

Interest

AOI Location Rationale Potential

Future Action

AOI 1:

Grass Fire

near Flight

Line

29°25'51.98"N;

98°22'39.68"W

One or more Tri-MaxTM units were used

to put out a grass fire near the southeast

end of the flight line. AFFF would most

likely have infiltrated into the

surrounding grassy area and may have

collected in nearby surface water and

sediment.

Proceed to an

SI, focus on

soil, surface

water/sediment,

and

groundwater

AOI 2: Area

East of the

Maintenance

Hangar

29°26'07.1"N;

98°22'50.4"W

AFFF was potentially released in this

area while Tri-MaxTM units were being

emptied by an outside contractor.

Additionally, the fire truck historically

located further east of this area was

most likely equipped with AFFF, which

may have leaked into the ground over

the years. AFFF releases in this area

would have infiltrated into soil and

potentially groundwater.

Proceed to an

SI, focus on soil

and

groundwater

AOI 3: Wash

Rack

29°26'05.7"N;

98°22'51.6"W

During Tri-MaxTM maintenance events,

AFFF may have been disposed at the

wash rack. These fluids would travel to

the OWS, and depending on the position

of a diverter valve, would either flow via

underground piping to the sanitary

sewer, or through a series of manholes

to Rosillo Creek and then Salado Creek.

Leaks in the underground piping may

have led to AFFF infiltrating into soil and

reaching the subsurface.

Proceed to an

SI, focus on

soil, surface

water/sediment,

and

groundwater
Armory

Flint Hills

Resources

Grass Fire

Wash Rack

Storage Area

 for Tri-Max units 

waiting for repair

Landfill

Historic Location

of Fire Truck

AZZ Galvanizing

San Antonio

Blue Beacon

Truck Wash

Fuel Station

Storage Hangar

Maintenance Hangar

AOI 1

AOI 3

AOI 2

Rosillo Creek

0 600 1,200 2,400

Feet

Legend

Area of Interest

Potential PFAS Release

No Suspected Release

Facility Boundary

Water Body

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Summary of Findings

12420 Milestone Center Drive

Germantown, MD 20876

30
PFAS Preliminary Assessment Report

Martindale AASF, TX

San Antonio, TX

31

8. References

Bureau of Economic Geology, University of Texas at Austin, 1982. Geologic Atlas of Texas, San

Antonio Sheet, https://www.twdb.texas.gov/groundwater/aquifer/GAT/san-antonio.htm,

Accessed 14 January 2020.

Interstate Technology Regulatory Council. November 2017. History and Use of Per- and

Polyfluoroalkyl Substances (PFAS). https://pfas-1.itrcweb.org/wpcontent/uploads/2017/11/pfas_fact_sheet_history_and_use__11_13_17.pdf. Accessed 12

December 2019.

National Weather Service Forecast Office. 2019. Austin/San Antonio, TX. Preliminary Monthly

Climate Data. https://w2.weather.gov/climate/index.php?wfo=ewx. Accessed 22 October 2019.

Texas Board of Water Engineers (TBWE). August 1954. Ground-water Resources of the San

Antonio Area, Texas, A Progress Report of Current Studies, by Joe W. Lang, Geologist, United

States Geological Survey.

http://www.twdb.texas.gov/publications/reports/bulletins/doc/B5412.pdf. Accessed 11 September

2019.

TBWE, 1959. Bulletin 5911: Ground-Water Geology of Bexar County, Texas.

http://www.twdb.texas.gov/publications/reports/bulletins/doc/B5911/B5911.pdf. Accessed 14

January 2020.

U.S. Army Center for Health Promotion and Preventive Medicine (USACHPPM). January 1997.

Site Assessment Survey No. 38-EH-5684-97. Texas Army National Guard. Martindale Army

Aviation Support Facility. San Antonio, Texas.

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

Preliminary Assessments under CERCLA. EPA/540/G-91/013. September 1991.

Weather Atlas. 2019. San Antonio, TX – Detailed climate information and monthly weather

forecast. The climate of San Antonio. https://www.weather-us.com/en/texas-usa/san-antonioclimate. Accessed 26 August 2019.
PFAS Preliminary Assessment Report

Martindale AASF, TX

San Antonio, TX

Appendix A

Data Resources
PFAS Preliminary Assessment Report

Martindale AASF, TX

San Antonio, TX

Data resources will be provided separately on CD. Data resources for Martindale AASF include:

Previous Investigations Completed

· U.S. Army Center for Health Promotion and Preventive Medicine. January 1997. Site

Assessment Survey No. 38-EH-5684-97. Texas Army National Guard. Martindale Army

Aviation Support Facility. San Antonio, Texas.

Miscellaneous Data Resources

· Map 3 – Facility Drainage Area. Drainage Map, Martindale. Provided by the Texas Military

Department.

· EDRTM Aerial Photo Decade Package, December 2019. Martindale AASF, 1112 Ackerman

Rd, San Antonio, TX 78219.

· EDRTM Radius Map Report with GeoCheck, December 2019. Martindale AASF, 1112

Ackerman Rd, San Antonio, TX 78219.

· EDRTM Certified Sanborn Map Report, December 2019. Martindale AASF, 1112 Ackerman

Rd, San Antonio, TX 78219.
PFAS Preliminary Assessment Report

Martindale AASF, TX

San Antonio, TX

Appendix B

Preliminary Assessment Documentation
PFAS Preliminary Assessment Report

Martindale AASF, TX

San Antonio, TX

Appendix B.1

Interview Records



PFAS Preliminary Assessment Report

Martindale AASF, TX

San Antonio, TX

Appendix B.2

Visual Site Inspection Checklists

PFAS Preliminary Assessment Report

Martindale AASF, TX

San Antonio, TX

Appendix B.3

Conceptual Site Model Information



PFAS Preliminary Assessment Report

Martindale AASF, TX

San Antonio, TX

Appendix C

Photographic Log
Preliminary Assessment Report

Martindale AASF San Antonio, TX

Perfluorooctane-Sulfonic Acid (PFOS) and 

Perfluorooctanoic Acid (PFOA) Impacted Sites

ARNG Installations, Nationwide

AECOM

APPENDIX C – Photographic Log

Army National Guard, Preliminary

Assessment for PFAS Martindale AASF (April 24, 2019) San Antonio, Texas

Photograph No. 1

Description:

Storage hangar and flightline. 

Facing north. Historically 1 

Tri-Max unit located in 

hangar. No fire suppression 

system. No known releases. 

Photograph No. 2

Description: 

Helicopters stationed along 

flight line. Photo facing 

southwest. Historically 2-3 

Tri-Max units located along 

flight line. No known releases. 

24 April 2019

24 April 2019