FINAL

Preliminary Assessment Report

Tulsa Army Aviation Support 

Facility #2

Oklahoma

Perfluorooctanesulfonic Acid (PFOS) and Perfluorooctanoic

Acid (PFOA) Impacted Sites

ARNG Installations, Nationwide 

October 2020 

Prepared for:

Army National Guard Bureau

111 S. George Mason Drive

Arlington, VA 22204

UNCLASSIFIED
PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma

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Table of Contents

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

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

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

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

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

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

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

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

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

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

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

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

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

2.1 Tri-Max Training Areas 1, 2, and 3 ..........................................................................11

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

3.1 Storage Hangar ......................................................................................................12

3.2 Maintenance Hangar...............................................................................................12

3.3 HEMTT Storage......................................................................................................13

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

3.5 Evaporator..............................................................................................................13

3.6 Building 100............................................................................................................13

3.7 Maintenance Room................................................................................................. 13

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

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

5.1 Tulsa ANGB............................................................................................................17

5.2 Air Force Plant #3 ...................................................................................................17

5.3 Landfills ..................................................................................................................17

5.4 Northside WWTP....................................................................................................17

5.5 WWTP Sludge Spreading Area...............................................................................17

5.6 Fire Stations 31 & 51 ..............................................................................................17

5.7 United Plating Works, Inc........................................................................................18

5.8 Semi-Truck Explosion .............................................................................................18

6. Preliminary Conceptual Site Model ..................................................................................20

6.1 Pathways ................................................................................................................20

6.2 Receptors ...............................................................................................................20

6.3 AOI 1: Eastern Release Areas ................................................................................21

6.4 AOI 2: Western FTAs ..............................................................................................21

6.5 AOI 3: HEMTT Storage...........................................................................................22

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

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

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

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

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

Tulsa AASF #2, Tulsa, Oklahoma

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Figures

Figure ES-1 Summary of Findings

Figure ES-2 Preliminary Conceptual Site Model, Tulsa AASF #2

Figure 1-1 Facility Location

Figure 1-2 Groundwater Features

Figure 1-3 Surface Water Features

Figure 2-1 Fire Training Areas

Figure 3-1 Non-Fire Training Areas

Figure 5-1 Adjacent Sources

Figure 6-1 Areas of Interest

Figure 6-2 Preliminary Conceptual Site Model, AOI 1 Eastern Release Areas, AOI 2 Western 

FTAs, and AOI 3 HEMTT Storage

Figure 7-1 Summary of Findings

Tables 

Table ES-1 AOIs at Tulsa AASF #2

Table 6-1 Exposure Pathways at the AOIs

Table 7-1 AOIs at Tulsa AASF #2

Table 7-2 No Suspected Release Areas 

Table 7-3 Uncertainties 

Table 7-4 PA Findings Summary

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

Tulsa AASF #2, Tulsa, Oklahoma

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Acronyms and Abbreviations

°F degrees Fahrenheit

AECOM AECOM Technical Services, Inc.

AASF Army Aviation Support Facility

AFFF aqueous film forming foam

amsl above mean sea level

ANGB Air National Guard Base

AOI area of interest

ARNG Army National Guard

bgs below ground surface

CERCLA Comprehensive Environmental Response, Compensation, and Liability Act

CSM conceptual site model

EDRTM Environmental Data Resources, Inc.TM

FTA fire training area

HA Health Advisory

HEMTT heavy expanded mobility tactical truck

ng/L nanograms per liter

OKARNG Oklahoma Army National Guard

OWS oil/water separator 

PA Preliminary Assessment

PFAS per- and polyfluoroalkyl substances

PFOA perfluorooctanoic acid

PFOS perfluorooctanesulfonic acid

SI Site Inspection

UCMR3 Unregulated Contaminant Monitoring Rule 3

US United States

USACE United States Army Corps of Engineers

USEPA United States Environmental Protection Agency

VSI visual site inspection

WWTP wastewater treatment plant
PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma

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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 Tulsa Army Aviation Support Facility (AASF) #2 

in Tulsa, Oklahoma 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 17 October 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 are associated with AASF #2 activities

including the maintenance test pilot, the facility manager, a facility supervisor, a computer

assistant, an aircraft mechanic, and one quality control personnel;

• Developed a preliminary conceptual site model (CSM) to outline the potential release,

pathway, and receptors of PFAS for the Tulsa AASF #2.

Nine potential PFAS source areas were identified during the PA. These source areas constitute 

three Areas of Interest (AOIs) identified at the Tulsa AASF #2. The AOIs are shown in Figure ES1 and summarized in Table ES-1. 

Table ES-1: AOIs at Tulsa AASF #2

Area of 

Interest

Name Used by Potential Release 

Dates

AOI 1 Eastern Release Areas OKARNG 1990s to 2014

AOI 2 Western FTAs OKARNG 1990s-early 2000s

AOI 3 HEMTT Storage OKARNG 1990s-early 2000s

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

contamination in media at or near the facility. The preliminary CSM for the AOIs is shown in 

Figure ES-2, which presents the potential receptors and media impacted. 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 Advisory (HA) within 20 miles of the facility. The HA is 70 parts per trillion for PFOS 

and PFOA, individually or combined. PFAS analyses performed in 2016 had method detection 

limits that were higher than currently achievable. Thus, it is possible that low concentrations of 

PFAS were not detected during the UCMR3 but might be detected if analyzed today.
United Plating

Works, Inc.

Waste Management

Landfill

C&D Landfill

Fire Station 51 Fire Station 31

Air Force

Plant #3

Northside WWTP

Tulsa ANGB

WWTP Sludge

Spreading Area

Semi-Truck

Explosion

Coal Creek

Bird Creek

M ingo

Creek

Bird Creek

Bird C reek

Mill Creek

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

Geographics, CNES/Airbus DS, USDA, USGS,

Figure ES-1

Summary of Findings

Legend

Area of Interest

Potential PFAS Release

No Suspected Release

Facility Boundary

Water Body

River/Stream

Pipeline

AOI 1

AOI 2

AOI 3

Maintenance Room

Tri-Max Training Area 1

Tri-Max Training Area 2

Tri-Max Training Area 3

HEMTT Storage

Maintenance Hangar

Storage Hangar

Wash Rack

Building 100

Evaporator

Drain Pipe to

Mingo Creek

OWS to City Sewer

OWS to Evaporator

Mingo Creek

0 2,250 4,500 9,000

Feet

0 250 500 1,000

Feet

2
Media

SOURCE PATHWAY RECEPTOR

AOI 1

AOI 2

AOI 3

Fire Training

Activities, Fire

Suppression

System Release,

Aircraft Washing,

and Spills

PFAS in

Surface Soil

and Surface

Water

Human

Activities

Precipitation/

Run-Off

Leaching/

Infiltration

Airborne Soil

Particulate

Surface

Water/

Sediment

Shallow

Groundwater

Source Release

Mechanism Media Transportand Migration Media ExposureRoutes

Inhalation of

Dust

Ingestion

Human Receptors:

Current/ Future

Flow-Chart Continues

Partial / Possible Flow

Flow-Chart Stops

Incomplete Pathway

Potentially Complete Pathway

Complete Pathway

Site

Worker

Construction

Worker Resident Recreational User

Site

Worker

Construction

Worker Resident Recreational User

LEGEND

Figure ES-2

Preliminary Conceptual Site Model

Tulsa AASF #2

/ /

/ / /

Ingestion

/ / / /

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.

/ /

/

Ingestion

Ingestion

/

Potential

Off-Facility

Source Not

under

Control of

ARNG

/

/ /

Surface Soil

at AOIs

Subsurface

Soil

/ /

/

/

3
PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma

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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) 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 polyfluoroalkyl substances (PFAS), primarily in the form of aqueous film 

forming foam (AFFF) released as part of firefighting activities, 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. 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 Drinking Water Health 

Advisories (HAs) 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 findings of a PA for PFAS at Tulsa Army Aviation Support Facility (AASF) #2

(also referred to as the “facility”) in Tulsa, Oklahoma, 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-containing materials were historically stored and 

reportedly released into the environment at Tulsa AASF #2. 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 17 October 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 are associated with AASF #2 activities

including the maintenance test pilot, the facility manager, a facility supervisor, a computer

assistant, an aircraft mechanic, and one quality control personnel;
PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma 

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• Developed a preliminary conceptual site model (CSM) to outline the potential release, 

pathway, and receptors of PFAS for Tulsa AASF #2. 

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 as follows: 

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

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

• Section 2 – Fire Training Areas: describes the 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

The Tulsa AASF #2 encompasses approximately 47 acres of land in Tulsa County, northeast 

Oklahoma (Figure 1-1). The facility is situated at the junction of US Highway 169 and Oklahoma 

Highway 266 and is northeast of Tulsa International Airport and a mile east of the Tulsa Air 

National Guard Base (ANGB). 

The Tulsa AASF #2 was built in 1987 and the Oklahoma ARNG (OKARNG) moved into the facility 

in 1989. Prior to construction, the land was previously agricultural or undeveloped land. The 

mission of the facility is to support aviation equipment and machinery and maintain properly 

trained and equipped units ready for mobilization and includes a storage hangar, maintenance 

hangar, heavy expanded mobility tactical truck (HEMTT) storage area, and armory.

1.5 Facility Environmental Setting

The facility is within the geomorphic province of Claremore Cuesta Plains, which is characterized 

by westward dipping Pennsylvanian-aged sandstones and limestones, which form cuestas 

between broad shale plains (Tyrl et al., 2007). The topography at the facility is relatively flat with 

surface elevations ranging from about 600 to 610 feet above mean sea level (amsl).
PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma

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1.5.1 Geology

The geology at the facility is characterized by Quaternary-aged alluvial deposits and 

Pennsylvanian-aged rocks, which dip to the west (Miller and Stanley, 2006; Tyrl et al., 2007). The 

surficial geology near the facility consists of alluvium, located near Mingo Creek, and the Oologah 

Formation. The alluvium in the Tulsa region is composed of clay, silt, sand, and gravel and ranges 

in thickness from 0 to 30 feet (Marcher and Bingham, 1971; Miller and Stanley, 2006). The 

Oologah Formation is a Pennsylvanian-aged grayish limestone with intervals of sandstone or 

fossiliferous shale ranging up to 110 feet-thick (Marcher and Bingham, 1971; Miller and Stanley, 

2006). 

The Labette Formation underlies the Oologah Formation and is composed of shale and thin 

laminations of sandstone and limestone (Marcher and Bingham, 1971; Miller and Stanley, 2006). 

The thickness of the Labette Formation in the Tulsa region ranges from 220 to 260 feet-thick 

(Miller and Stanley, 2006). The Fort Scott Formation underlies the Labette Formation and

comprises two members: Little Osage Shale and Blackjack Creek Limestone. The thickness of 

the Fort Scott Formation ranges from 7 to 12 feet (Miller and Stanley, 2006). Underlying the Fort 

Scott Formation is the Senora Formation, which consists of a silty to sandy shale with thin 

laminations of sandstone (Marcher and Bingham, 1971; Miller and Stanley, 2006). The Senora 

Formation is underlain by other Pennsylvanian and older units. Geologic units underlying the 

facility are displayed on Figure 1-2.

1.5.2 Hydrogeology

There is no principal aquifer in the Tulsa area (Johnson, 1983). While groundwater exists in the 

Pennsylvanian rocks found at the facility, they are not ideal for groundwater resources with most 

wells yielding an estimated rate of 0.5 gallons per minute. The Oologah Formation, which is 

stratigraphically the uppermost unit at the facility, yields small quantities of fair to poor quality 

water (Marcher and Bingham, 1971). 

Subsurface investigative work completed at the C&D landfill, located approximately 1 mile east of 

the facility, indicated groundwater depths vary but are typically at the contact of the Oologah and 

Labette formations or the first 10 feet of the Labette Formation. The boring logs of this work 

indicate the contact between limestone and shale occurs around 532 to 565 feet amsl (E&E 

Engineering and Associates, LLC, 2018). The inferred groundwater flow direction at the facility is 

northwest. An SI completed in 2018 at the adjacent Tulsa ANGB reported groundwater levels in 

soil borings and monitoring wells that ranged from 4.78 to 25 feet below ground surface (bgs) with 

groundwater flow bifurcating from the south to the northwest and east/northeast (Leidos, 2018).

The facility’s drinking water is supplied by the City of Tulsa, which acquires its water from Lake 

Spavinaw, Lake Eucha and Lake Oologah. Lakes Spavinaw and Eucha are located approximately 

46 and 52 miles east of the facility, respectively. Lake Oologah is about 17.5 miles northeast of 

the facility. An EDRTM report conducted a well search for a 1-mile radius surrounding the facility 

(Appendix A). Using additional online resources, such as state and local GIS databases, wells 

were researched to a 4-mile radius of the facility. Groundwater features in the four-mile radius 

surrounding the facility are shown in Figure 1-2. Within a 2.5-mile radius of the facility there are 

three domestic wells, whose total depths range from 21 to 197 feet bgs. Additionally, there are 

numerous monitoring wells to the east and west of the facility at the Tulsa ANGB and two landfills. 

Most of these wells have total depths ranging from 10 to 60 feet bgs (Oklahoma Water Resource 

Board, 2020).Consequently, groundwater in the water table aquifer may be expected at a similar 

depth.

Based on USEPA’s 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 Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma

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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 

Surface water near the facility includes Mingo Creek to the west. Mingo Creek flows northward 

into Bird Creek, which is a tributary of the Verdigris River. The inferred overland flow direction at 

the facility is to the northwest and eventually drains into Mingo Creek. Surface water features 

surrounding the facility are shown in Figure 1-3. 

1.5.4 Climate 

The facility is in the City of Tulsa. The average temperature of Tulsa is 60.7 degrees Fahrenheit 

(°F). Seasonally, temperatures vary from a summer average monthly high of 93 °F to a winter 

average monthly low of 28 °F. Average precipitation in Tulsa is 40.91 inches (World Climate, 

2020).

1.5.5 Current and Future Land Use

The facility currently includes a storage hangar, maintenance hangar, HEMTT storage area, and 

armory. Reasonably anticipated future land use is not expected to change from the current land 

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

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

Figure 1-1

Facility Location

Legend

Facility Boundary

0 1 2 4

Miles

Tulsa AASF #2

^_

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Flat Rock Creek

Coal Creek

ElmCreek

R anc hCre ek

Mill Creek

M ingoCreek

Bird Creek

­12420 Milestone Center Drive

Germantown, MD 20876

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Base Map: Source: Esri, DigitalGlobe, GeoEye,

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

Figure 1-2

Groundwater Features

Facility Boundary

River/Stream

Pipeline

Water Body

Wetland

Inferred Groundwater Flow Direction

Geology

Alluvium

Seminole Formation

Holdenville and Lenapah Formations

Nowata Formation

Oologah Formation

Labette Formation

Senora Formation

Wells

!5 Agriculture Well

!P Commercial

!P Domestic Well

A! Observation/Monitoring Well

0 0.75 1.5 3

Miles

9
Coal C re ek

E lm Cr e ek

Bird Creek

MingoCr eek

Mingo Creek

Watershed

Ranch Creek-Bird

Creek Watershed

Elm Creek-Bird

Creek Watershed

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Base Map: Source: Esri, DigitalGlobe, GeoEye,

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

Figure 1-3

Surface Water Features

Legend

Facility Boundary

Water Body

Wetland

River/Stream

Pipeline

Surface Water Flow

Direction

0 0.25 0.5 1

Miles

10
PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma

11

2. Fire Training Areas

Three FTAs were identified at the Tulsa AASF #2 during the PA. The FTAs are described below 

and shown on Figure 2-1. 

2.1 Tri-Max Training Areas 1, 2, and 3

The facility obtained eight Tri-MaxTM extinguishers in the 1990s and trained with the units on three 

occasions. One extinguisher was completely discharged during each training event. The training 

events occurred in three different locations, designated as Tri-Max Training Area 1, 2, and 3. The 

geographic coordinates of Tri-Max Training Areas 1, 2, and 3 are 36°13’00.8”N, 95°51’12.6”W; 

36°12’57.0”N, 95°51’14.7”W; and 36°12’55.1”N, 95°51’18.2”W; respectively. A few extinguishers 

were located at the HEMTT Storage but the locations of the remaining units are unknown. No 

information was provided regarding the dates of the training events. The Tri-MaxTM extinguishers 

were subsequently removed from use in the early 2000s. In 2011 the Tri-MaxTM extinguishers 

were shipped to the US Property and Fiscal Office for Oklahoma. 
Mingo Creek

Drain Pipe to

Mingo Creek

OWS to

City Sewer

OWS to

Evaporator

Tri-Max

Training

Area 1

Tri-Max

Training

Area 2

Tri-Max

Training

Area 3

­12420 Milestone Center Drive

Germantown, MD 20876

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Base Map: Source: Esri, DigitalGlobe, GeoEye,

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

Figure 2-1

Fire Training Areas

Legend

Potential PFAS Release

Facility Boundary

Water Body

River/Stream

0 200 400 800

Feet

12
PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma

13

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. Seven non-FTAs where 

AFFF was stored and/or potentially released were identified during the PA. A description of each 

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

3.1 Storage Hangar

The Storage Hangar is located between the Maintenance Hangar and the Evaporator. The 

geographic coordinates are 36°13’00.4”N; 95°51’11.3”W. The Storage Hangar houses two 300-

gallon foam tanks, located along the northern wall, and three 36-gallon manual AFFF tanks, 

located along the north, east, and south walls, that were obtained in 2013. The 300-gallon foam 

tanks are filled with 2.2% Buckeye Hi-Ex foam. Foam is replaced by contractors based in Houston, 

Texas. No information was provided on the disposal of AFFF and Buckeye Hi-Ex after it leaves 

the facility or when this occurred. 

In 2014, a fire suppression system was installed, which conveys Buckeye Hi-Ex foam to three 

overhead sprayers in the Storage Hangar and two overhead sprayers in the Maintenance Hangar. 

The system was tested twice after installation. During both tests, plastic was placed around both 

the Storage Hangar and the Maintenance Hangar to prevent foam from leaving the hangars. The 

first test failed because not enough foam was produced by the system and only a small area of 

hangars was filled with foam. No information was provided on the type of foam used in the first 

test. Consequently, 2.2% Buckeye Hi-Ex foam was acquired, and a second test was conducted. 

The second test was meant to test whether both hangars would be adequately covered by the 

fire suppression system. The hangars were taped up in order to seal them so foam would not leak 

out of the hangars. The second test was successful, and the hangars filled up with 8 or 9 feet of 

foam. Only an estimated 5-10 gallons of Buckeye Hi-Ex foam were released during the second 

test. After both tests, the facility personnel let the foam settle and pushed it down to the trench 

drain, which transports wastewater to an oil/water separator (OWS), then to the City of Tulsa 

sanitary sewer, and, eventually, to the Northside Wastewater Treatment Plant (WWTP). 

In August 2014, the fire suppression system was accidentally triggered, and one of the 300-gallon 

foam tanks released into the Storage Hangar. Buckeye Hi-Ex foam spilled out through the Storage 

Hangar doors into the Maintenance Hangar and onto the ramp. Videos of the aftermath show up 

to around 4 feet of foam, which spread approximately 300 feet northward on the ramp and into 

the grassy area just north of the Storage Hangar and approximately 350 feet westward into the 

grassy area between the ramp and the runway. Facility personnel allowed the foam to settle and 

evaporate. The helicopters on the ramp that were covered by foam were washed at the Wash 

Rack. It is estimated that 300 gallons of Buckeye Hi-Ex foam was released during the accidental 

triggering of the fire suppression system.

3.2 Maintenance Hangar

The Maintenance Hangar is located south of the Storage Hangar and north of the Maintenance 

Room. The geographic coordinates are 36°12’59.1”N; 95°51’11.3”W. Two 36-gallon AFFF tanks

were obtained in 2013 and are stored in the Maintenance Hangar, one on the north side of the 

hangar, and one on the south side. Buckeye Hi-Ex foam filled the Maintenance Hangar during the 

second testing of the fire suppression system, to 8 or 9 feet. Only an estimated 5-10 gallons of 

foam were released during the second test. Additionally, an unknown amount of Buckeye Hi-Ex 

foam spilled into the Maintenance Hangar during the August 2014 accidental fire suppression 
PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma

14

system release event. Any PFAS releases in the Maintenance Hangar would flow to the trench 

drain, then to the OWS and, eventually, to the Northside WWTP via the sanitary sewer. 

3.3 HEMTT Storage

The HEMTT Storage area is located north of the ramp. The geographic coordinates are 

36°13’06.7”N; 95°51’12.8”W. The HEMTTs are used as mobile refuelers at the facility. Tri-MaxTM 

extinguishers were located at the HEMTT Storage from the 1990s to the early 2000s when the 

extinguishers were removed from the facility. There are no reported releases of AFFF at this 

location.

3.4 Wash Rack

The Wash Rack is located 50 feet northwest of the Storage Hangar and west of the Evaporator. 

The geographic coordinates of the Wash Rack are 36°13’01.9”N; 95°51’12.1”W. The Wash Rack 

was used to wash the Buckeye Hi-Ex foam off the helicopters after the accidental fire suppression 

release event. The Wash Rack effluent drains to an OWS and is then conveyed to a holding tank. 

Water in the holding tank is reused by the facility to wash aircraft. The excess water is burned off 

at the evaporator.

Multiple types of OWS have been used at the facility, the previous OWS system included a 

defoamer, which conveyed the wastewater to Mingo Creek and a system that had a filter in the 

Petroleum, Oil, and Lubricant Storage building with an underground plate system. The current 

OWS is a recycle system with an evaporator and was installed in 2010. A valve on the system 

allows water to be discharged to nearby Mingo Creek, but this only occurs after a large rain event 

and once the water has been checked for a sheen. However, prior to 2010, water was discharged 

more frequently to the creek. Historically, foam has been observed in the creek, although it is 

unknown whether this was related to a release of AFFF.

3.5 Evaporator

The Evaporator is located just north of the Storage Hangar. The geographic coordinates are 

36°13’01.6”N; 95°51’11.2”W. The Wash Rack effluent drains to an OWS and then to a holding 

tank. Any excess water is burned off at the Water Maze® Evaporator, which was installed in 2010. 

AFFF or Buckeye Hi-Ex foam discharged at the Wash Rack could be conveyed to the Evaporator. 

Solids from the wash water evaporation process are removed and disposed of by a contractor on 

routine basis. No information was available regarding the offsite disposal of the solid waste.

3.6 Building 100

Building 100 is located east of the ramp and approximately 100 feet northeast of the evaporator. 

The geographic coordinates are 36°13’02.8”N; 95°51’10.4”W. Historically, 25 five-gallon buckets 

of AFFF were stored at this location. The buckets were donated to a local fire station at an 

unknown date. No information was available on the concentration or type of AFFF stored in the 

buckets. No leaks or spills were reported. No AFFF is currently stored in Building 100.

3.7 Maintenance Room

The Maintenance Room is located south of the Maintenance Hangar. The geographic coordinates 

of the Maintenance Room are 36°12’57.5”N; 95°51’11.6”W. The Maintenance Hangar previously

housed the facility firetruck; however, the truck was not equipped with AFFF. Interviewees 
PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma

15

indicated firefighting vehicles and helicopters are equipped with Purple-K. No information was 

available regarding the dates the firetruck arrived or removed from the facility.
Maintenance

Room

HEMTT Storage

Maintenance

Hangar

Storage

Hangar

Wash Rack

Building 100

Evaporator Drain Pipe to

Mingo Creek

OWS to

City Sewer

OWS to

Evaporator

Mingo Creek

­12420 Milestone Center Drive

Germantown, MD 20876

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Base Map: Source: Esri, DigitalGlobe, GeoEye,

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

Figure 3-1

Non-Fire Training Areas

Legend

Potential PFAS Release

No Suspected Release

Facility Boundary

Water Body

River/Stream

0 200 400 800

Feet

16
PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma

17

4. Emergency Response Areas

During the PA no historic emergency responses were identified at the facility. Emergency 

response at the facility is provided by the Tulsa Fire Department located at the Tulsa International 

Airport. Interviewees had no recollection of the city fire department training at the Tulsa AASF #2. 
PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma

18

5. Adjacent Sources

Eight adjacent sources of potential PFAS, not under the control of OKARNG were identified. 

These off-facility sources include: Tulsa ANGB, Air Force Plant #3, two landfills, Northside WWTP, 

WWTP Sludge Spreading Area, two fire stations, and United Plating Works, Inc. Figure 5-1

displays the adjacent sources described in this section. 

5.1 Tulsa ANGB

The Tulsa ANGB is less than a mile to the west of the facility. An SI report dated November 2018 

identified multiple areas where AFFF was discharged. PFAS was confirmed in soil and 

groundwater. PFOA and PFOS exceeded the USEPA HA (70 nanograms per liter [ng/L]) for 

groundwater with PFOA+PFOS reaching concentrations as high as 47,400 ng/L (Leidos, 2018).

5.2 Air Force Plant #3

The Air Force Plant #3 is approximately 1.5 miles to the southwest of the facility, near the Tulsa 

International Airport. An SI report dated August 2018 focused on AFFF discharges in surface soil. 

The report detected PFAS in soil and groundwater and PFOA and/or PFOS above the USEPA HA 

in groundwater with PFOA+PFOS reaching concentrations as high as 436 ng/L (Oneida Total 

Integrated Enterprises, 2018). 

5.3 Landfills

There are two landfills approximately a mile east of the facility, C&D Landfill and the Waste 

Management Landfill. 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 WWTP that processes PFAS-laden water, used AFFF storage containers, or 

products associated with waterproofing uniforms or boots. However, no information obtained 

indicates PFAS-related materials were disposed of at these landfills. 

5.4 Northside WWTP 

Northside WWTP is approximately 1 mile north of the facility. The WWTP was constructed in 1958 

and treats the local wastewater conveyed from the Tulsa AASF #2 and the wastewater from 

adjacent potential PFAS source areas, such as the Tulsa ANGB and Air Force Plant #3. Little 

information was available on the disposal of the sludge generated at the WWTP. 

5.5 WWTP Sludge Spreading Area

The WTTP Sludge Spreading Area is located to the east, directly adjacent to the facility and across 

Mingo Valley Expressway (Highway 169). The Northside WWTP historically spread sludge at the 

WWTP Sludge Spreading Area. Information on when the sludge spreading practice was started 

is unclear, but development in the area began approximately in 2012; therefore, the spreading 

process may have ceased prior to 2012.

5.6 Fire Stations 31 & 51

Fire Station 31 is located on the eastern side of the Tulsa International Airport and Fire Station 51 

is located in the center of the airport. These fire stations received 25 five-gallon buckets of AFFF 

from the OKARNG. The storage and use of the AFFF by the fire stations are unknown.
PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma

19

5.7 United Plating Works, Inc.

United Plating Works, Inc. is approximately 1.5 miles southwest of the facility, just north of Air 

Force Plant #3. United Plating Works, Inc. provides various metal plating services, including 

chrome plating. Metal plating often involves the use of PFAS for mist suppression; however, no 

information could be obtained regarding the use of PFAS at this location. Interviewees also 

indicated that the United Plating, Inc. was formerly located further south of the facility at the 

intersection of E Pine Street and Mingo Express Highway.

5.8 Semi-Truck Explosion

In June 2019, a semi-truck collision resulted in an explosion. The explosion occurred 

approximately 4.5 miles south of the facility at the junction of I-44 and Highway 169. The Tulsa 

Fire Department responded to the emergency and discharged firefighting foam in unknown 

quantities to put out the fire (Fox 23 News, 2019). 
United Plating

Works, Inc.

Waste Management

Landfill

C&D Landfill

Fire Station 51 Fire Station 31

Air Force

Plant #3

Northside WWTP

Tulsa ANGB

WWTP Sludge

Spreading Area

Semi-Truck

Explosion

Coal Creek

Mill Creek

Bird Creek

Bird Creek

M ingo

Creek

Bird Creek

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

Geographics, CNES/Airbus DS, USDA, USGS,

Figure 5-1

Adjacent Sources

Legend

Potential PFAS Release

No Suspected Release

Facility Boundary

Water Body

River/Stream

Pipeline

0 2,250 4,500 9,000

Feet

20
PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma

21

6. Preliminary Conceptual Site Model

Based on the PA findings, three AOIs were identified at the Tulsa AASF #2: AOI 1 Eastern Release 

Areas, AOI 2 Western FTAs, and AOI 3 HEMTT Storage. Locations of the AOIs are shown on 

Figure 6-1. The preliminary CSM for AOIs 1, 2, and 3 is shown on Figure 6-2. The following 

sections describe the CSM components and the specific preliminary CSMs developed for each 

AOI. The CSM identifies the three components necessary for a potentially complete exposure 

pathway: (1) source, (2) pathway, (3) receptor. If any of these elements are missing, the pathway 

is considered incomplete.

6.1 Pathways

In general, the potential PFAS exposure pathways are ingestion and inhalation. Human exposure 

via the dermal contact pathway may occur, and current risk practice suggests it is an insignificant 

pathway compared to ingestion; however, exposure data for dermal pathways are sparse and 

continue to be the subject of PFAS toxicological study (National Ground Water Association, 2018).

Known and potential AFFF releases identified at the Tulsa AASF #2 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 the surface soils 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 the Tulsa AASF #2 is provided by the City of Tulsa, which is sourced from three 

lakes located 17 to 52 miles northeast and east of the facility. Within a 2.5-mile radius of the 

facility, there are three domestic wells (Oklahoma Water Resource Board, 2020). It is possible 

that unregistered, private, domestic wells exist downgradient of the facility. Wells downgradient of 

the facility may result in potential exposure via ingestion of groundwater.

Surface water runoff at the facility appears to drain northwest toward Mingo Creek. Additionally, 

drainage ditches in grassy areas convey runoff northwest into Mingo Creek. The current OWS 

system has a valve that allows water to be discharged to Mingo Creek, but this only occurs after 

a large rain event and once the water has been checked for a sheen. However, prior to 2010, 

water was discharged more frequently to the creek. Mingo Creek flows northward into Bird Creek, 

which is a tributary of the Verdigris River, and may result in potential exposure via ingestion of 

surface water and sediment.

6.2 Receptors

Receptors at the Tulsa AASF #2 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.

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

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

activities.

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

users could be exposed to sediment and surface water during recreational use.
PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma

22

• Off-facility residents identify receptors who occupy properties outside of the Tulsa AASF #2.

Off-facility residents may come into contact with groundwater using private or domestic wells.

The preliminary CSMs for the Tulsa AASF #2 indicate which specific receptors could potentially 

be exposed to PFAS. The preliminary CSM for AOIs 1, 2, and 3 is shown on Figure 6-2. 

6.3 AOI 1: Eastern Release Areas

AOI 1 encompasses Tri-Max Training Area 1, Storage Hangar, Maintenance Hangar, Wash Rack,

Evaporator, and Building 100. Fire training activities occurred at Tri-Max Training Area 1 as early 

as the 1990s to as late as the early 2000s when the Tri-MaxTM extinguishers were removed from

use. The Tri-MaxTM extinguishers were removed from the facility in 2011. In 2014, the fire 

suppression system was tested twice, resulting in PFAS draining from the Storage and 

Maintenance Hangars via the trench drain. In August 2014, the fire suppression system was 

accidentally triggered, resulting in Buckeye Hi-Ex foam on the ramp and grassy areas.

Releases at AOI 1 have occurred on both paved areas and grassy surfaces. Some PFAS releases 

may have occurred directly onto surface soil but may also have infiltrated subsurface soil via 

cracks in pavement or joints between areas that are paved with different materials. PFAS are 

water soluble and can migrate readily from soil to groundwater via leaching. Overland surface 

water flow would result in the transport of PFAS from these release locations to Mingo Creek, 

west of the facility. Mingo Creek flows into Bird Creek north of the Tulsa AASF #2. Potential PFAS 

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

Table 6-1: Exposure Pathways at the AOIs

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 off-facility recreational users 

via ingestion

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

6.4 AOI 2: Western FTAs

AOI 2 encompasses Tri-Max Training Area 2 and Tri-Max Training Area 3 along the ramp and 

landing pad. Between the 1990s and the early 2000s, Tri-MaxTM extinguishers were used for fire 

training activities at these locations. One training activity occurred at each location and involved 

the use of one extinguisher.

Releases at AOI 2 occurred on paved surfaces. AFFF releases would flow northwestward, off the 

pavement toward Mingo Creek, potentially impacting surface soil. Additionally, AFFF may also 

have infiltrated subsurface soil via cracks in pavement or joints between areas that are paved with 

different materials. PFAS are water soluble and can migrate readily from soil to groundwater via 

leaching. Potential PFAS exposure pathways resulting from releases at AOI 2 are described in 

Table 6-1. 
PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma

23

6.5 AOI 3: HEMTT Storage

AOI 3 encompasses HEMTT Storage, which is a concrete-covered area that is located north of 

the ramp. Historically, Tri-MaxTM units were stored in this location. No known or recorded leaks or 

spills occurred at AOI 3. Any AFFF releases would flow northwestward, off the concrete and

potentially impacting surface soil. PFAS are water soluble and can migrate readily from soil to 

groundwater via leaching. Surface water flows to Mingo Creek. Potential PFAS exposure 

pathways resulting from releases at AOI 3 are described in Table 6-1. 
Maintenance Room

Tri-Max Training

Area 1

Tri-Max Training

Area 2

Tri-Max Training

Area 3

HEMTT Storage

Maintenance Hangar

Storage Hangar

Wash Rack

Building 100

Evaporator

Drain Pipe to

Mingo Creek

OWS to City Sewer

OWS to Evaporator

AOI 1

AOI 2

AOI 3

Mingo Creek

Watershed Mingo Creek

Mingo Creek

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

Geographics, CNES/Airbus DS, USDA, USGS,

Figure 6-1

Areas of Interest

Legend

Area of Interest

Potential PFAS Release

No Suspected Release

Facility Boundary

River/Stream

Surface Water Flow

Direction

Inferred Groundwater Flow

Direction

0 200 400 800

Feet

24
Media

SOURCE PATHWAY RECEPTOR

AOI 1

AOI 2

AOI 3

Fire Training

Activities, Fire

Suppression

System Release,

Aircraft Washing,

and Spills

PFAS in

Surface Soil

and Surface

Water

Human

Activities

Precipitation/

Run-Off

Leaching/

Infiltration

Airborne Soil

Particulate

Surface

Water/

Sediment

Shallow

Groundwater

Source Release

Mechanism Media Transportand Migration Media ExposureRoutes

Inhalation of

Dust

Ingestion

Human Receptors:

Current/ Future

Flow-Chart Continues

Partial / Possible Flow

Flow-Chart Stops

Incomplete Pathway

Potentially Complete Pathway

Complete Pathway

Site

Worker

Construction

Worker Resident Recreational User

Site

Worker

Construction

Worker Resident Recreational User

LEGEND

Figure 6-2

Preliminary Conceptual Site Model

AOI 1 Eastern Release Areas, AOI 2, Western FTAs, and AOI 3 HEMTT

Storage

/ /

/ / /

Ingestion

/ / / /

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.

/ /

/

Ingestion

Ingestion

/

Potential

Off-Facility

Source Not

under

Control of

ARNG

/

/ /

Surface Soil

at AOIs

Subsurface

Soil

/ /

/

/

25
PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma

26

7. Conclusions

This report presents a summary of available information gathered during the PA with respect to 

the use of AFFF and other PFAS-related activities at the Tulsa AASF #2. The PA findings are 

based on the information presented in Appendix A and Appendix B. 

7.1 Findings

Three AOIs related to potential PFAS releases were identified during the PA. A summary of the 

AOIs is shown in Table 7-1 and their location on Figure 7-1. 

Table 7-1: AOIs at Tulsa AASF #2

Area of Interest Name Used by Potential Release Dates

AOI 1 Eastern Release Areas OKARNG 1990s to 2014

AOI 2 Western FTAs OKARNG 1990s to early 2000s

AOI 3 HEMTT Storage OKARNG 1990s to early 2000s

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

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

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

The following area discussed in Section 3 was determined to have no suspected PFAS releases 

(Table 7-2):

Table 7-2: No Suspected Release Areas

No Suspected Release 

Area

Used by Rationale for No Suspected Release 

Determination

Maintenance Room OKARNG

No known or recorded instances of AFFF 

storage. Maintenance Hangar housed the 

firetruck, which was not equipped with AFFF.

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 or historically maintained by the facility or available during the PA 

with respect to the use of PFAS in training, firefighting, or other non-traditional activities, or 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 vague or conflicted with other sources. Gathered information has a degree of uncertainty due 

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

due to staffing changes, the time passed since PFAS was 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 
PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma

27

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

environment continually evolves.

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

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

for the same potential source area, and potential source areas were visually inspected. Table 7-

3 summarizes the uncertainties associated with the PA:

Table 7-3: Uncertainties

Area of Interest Source of Uncertainty

AOI 1 The dates at which the 25 five-gallon buckets of AFFF stored in 

Building 100 were obtained and donated are unknown. 

AOIs 1 and 2 The dates of training with the Tri-MaxTM extinguishers and the 

concentrations of AFFF in the extinguishers are unknown.

Tulsa AASF #2 The storage location of most of the Tri-MaxTM extinguishers and the 

concentrations of AFFF in the extinguishers are unknown. 

7.3 Potential Future Actions

Interviews and records (covering 1989 to present) indicate that current or former ARNG activities 

may have resulted in potential PFAS releases at the three AOIs identified during the PA. Based 

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

PFAS contamination in soil, groundwater, surface water, and sediment. Table 7-4 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 the AASF based on the potential receptors, the potential 

migration of PFAS contamination off the facility, and the availability of resources.
PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma

28

Table 7-4: PA Findings Summary

Area of 

Interest

AOI 

Location

Rationale Potential 

Future Action

AOI 1: 

Eastern 

Release 

Areas

36°13'00.3"N; 

95°51'11.2"W

Releases of AFFF to concrete during fire 

training activities from the 1990s to the 

early 2000s. Buckeye Hi-Ex foam released 

to concrete and surface soil during 

accidental triggering of the fire suppression 

system in 2014.

Proceed to an 

SI, focus on 

soil and 

shallow 

groundwater

AOI 2: 

Western 

FTAs

36°12'56.4"N; 

95°51'17.5"W

Releases of AFFF to concrete and surface 

soil during fire training activities from the 

1990s to the early 2000s.

Proceed to an 

SI, focus on 

soil and 

shallow 

groundwater

AOI 3: 

HEMTT 

Storage 

36°13'06.7"N; 

95°51'12.8"W AFFF was historically stored at AOI 3 from 

the 1990s to the early 2000s.

Proceed to an 

SI, focus on 

soil and 

shallow 

groundwater
United Plating

Works, Inc.

Waste Management

Landfill

C&D Landfill

Fire Station 51 Fire Station 31

Air Force

Plant #3

Northside WWTP

Tulsa ANGB

WWTP Sludge

Spreading Area

Semi-Truck

Explosion

Coal Creek

Bird Creek

M ingo

Creek

Bird Creek

Bird C reek

Mill Creek

­12420 Milestone Center Drive

Germantown, MD 20876

CLIENT

REVISED

SCALE

ARNG

GIS BY

CHK BY

SK

JH

6/24/2020

6/24/2020

NOTES Preliminary Assessment for PFAS at Tulsa AASF #2, OK

6/24/2020

1:54,000

PM RG 6/24/2020

C:\Users\samir.khadka\AECOM Directory\Stankevich, Michael - ARNG_PFAS_GIS_60552172\MXDs\OK\Tulsa_AASF_PA_Figures\Fig_7-1_Tulsa_AASF_Summary.mxd

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

Geographics, CNES/Airbus DS, USDA, USGS,

Figure 7-1

Summary of Findings

Legend

Area of Interest

Potential PFAS Release

No Suspected Release

Facility Boundary

Water Body

River/Stream

Pipeline

AOI 1

AOI 2

AOI 3

Maintenance Room

Tri-Max Training Area 1

Tri-Max Training Area 2

Tri-Max Training Area 3

HEMTT Storage

Maintenance Hangar

Storage Hangar

Wash Rack

Building 100

Evaporator

Drain Pipe to

Mingo Creek

OWS to City Sewer

OWS to Evaporator

Mingo Creek

0 2,250 4,500 9,000

Feet

0 250 500 1,000

Feet

29
PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma

30

8. References

E&E Engineering and Associates, LLC. 2018. Appendix F Groundwater Sampling and Analysis 

Plan. APAC East Quarry C&D Landfill, Tulsa County, Oklahoma, SW Permit No. 3572049. 

June.

Fox 23 News. 2019. Witnesses Recall Semi Explosions on East Tulsa Highway. Accessed 30 

April 2020 at https://www.fox23.com/news/semi-truck-on-fire-on-i-44/961994754/. June.

Johnson, Kenneth S. 1983. Maps Showing Principal Ground-water Resources and Recharge 

Areas in Oklahoma: Sheet 2 – Bedrock aquifers and Recharge Areas. Oklahoma Geological 

Survey, Geologic Map 43.

Leidos. 2018. Site Inspection Report for Perfluorooctane Sulfonate and Perfluorooctanoic Acid at 

Tulsa Air National Guard Base Tulsa, Oklahoma. November.

Marcher, M.V., and Bingham, R.H. 1971. Reconnaissance of the Water Resources of the Tulsa 

Quadrangle, Northeastern Oklahoma. Oklahoma State Geological Survey, Hydrologic Atlas 2. 

4 sheets.

Miller, G.W., and Stanley, T.M. 2006. Geologic Map of the Mingo 7.5’ Quadrangle, Rogers, Tulsa, 

and Wagoner Counties, Oklahoma. Oklahoma Geological Survey, Oklahoma Geologic 

Quadrangle 70.

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

Practice. January.

Oklahoma Water Resource Board. 2020. Groundwater Wells, Standards, and Protection in 

Oklahoma. 

https://owrb.maps.arcgis.com/apps/webappviewer/index.html?id=ed61209c40ec4f53bc51d2

ffd18aa39b (Accessed February 2020).

Oneida Total Integrated Enterprises. 2018. Final Site Inspection Report, Site Inspection of 

Aqueous Film Forming Foam (AFFF) Release Areas, Environmental Programs Worldwide, Air 

Force Plant #3 Tulsa, Oklahoma. August.

Tyrl, R.J., Bidwell, T.G., Masters, R.E., Elmore, R.D., and Weir, J.R. 2007. Oklahoma’s Native 

Vegetation Types. Oklahoma State University. Oklahoma Cooperative Extension Service 

Publication No. E-993.

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

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

World Climate. 2020. Average Weather Data for Tulsa, Oklahoma. 

http://www.worldclimate.com/climate/us/oklahoma/tulsa (Accessed February 2020).
PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma 

Appendix A

Data Resources
PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma

Appendix B

Preliminary Assessment Documentation
PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma 

Appendix B.1

Interview Records




PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma 

Appendix B.2

Visual Site Inspection Checklists

PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma 

Appendix B.3

Conceptual Site Model Information



PFAS Preliminary Assessment Report

Tulsa AASF #2, Tulsa, Oklahoma 

Appendix C

Photographic Log
Preliminary Assessment Report

Tulsa AASF #2 Tulsa, OK 

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 Tulsa AASF #2 (October 17, 2019) Tulsa, Oklahoma

Photograph No. 1

Description:

Photo facing north of oil/water 

separator that is located on the 

west side of the facility. This 

OWS receives wastewater 

from the trench drains in the 

hangars. 

Photograph No. 2

Description: 

Photo facing west of the flight 

line. Helicopters and mobile 

firefighting units (Purple-K) 

shown. Location of historic 

Tri-MaxTM Training Area 1. 
Preliminary Assessment Report

Tulsa AASF #2 Tulsa, OK 

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 Tulsa AASF #2 (October 17, 2019) Tulsa, Oklahoma

Photograph No. 3

Description:

Photo facing east of Storage 

Hangar. This hangar has a fire 

suppression system and three 

overhead foam sprayers (red 

unit attached to the ceiling on 

right side of photo). This is the 

location of the 2014 accidental 

triggering of the fire 

suppression system. 

Photograph No. 4

Description: 

View of the Storage Hangar 

facing northeast. Two foam 

ceiling spray nozzles are 

visible, as well as the two 300-

gallon foam tanks and one 36-

gallon manual AFFF tank 

along the north wall.
Preliminary Assessment Report

Tulsa AASF #2 Tulsa, OK 

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 Tulsa AASF #2 (October 17, 2019) Tulsa, Oklahoma

Photograph No. 5

Description:

Photo facing north of the 

historic Tri-MaxTM Training 

Area 1 located west of the 

Storage Hangar. 

Photograph No. 6

Description: 

Photo facing west of the 

historic and current wash rack. 
Preliminary Assessment Report

Tulsa AASF #2 Tulsa, OK 

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 Tulsa AASF #2 (October 17, 2019) Tulsa, Oklahoma

Photograph No. 7

Description:

Photo facing north of valve 

and OWS that is connected to 

the wash rack. 

Photograph No. 8

Description: 

Photo of the Water Maze® 

Evaporator; used to burn off 

excess wastewater from the 

wash rack. 
Preliminary Assessment Report

Tulsa AASF #2 Tulsa, OK 

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 Tulsa AASF #2 (October 17, 2019) Tulsa, Oklahoma

Photograph No. 9

Description:

Photo facing west of the 

holding tanks that are located 

between the OWS and the 

Water Maze® evaporator. 

Photograph No. 10

Description: 

Photo facing north of Building 

100. This is the location where 

historically 25 5-gallon 

buckets of AFFF were stored. 
Preliminary Assessment Report

Tulsa AASF #2 Tulsa, OK 

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 Tulsa AASF #2 (October 17, 2019) Tulsa, Oklahoma

Photograph No. 11

Description:

Inside of Building 100, where 

historically 25 5-gallon 

buckets of AFFF were stored. 

Photograph No. 12

Description: 

Photo facing north toward 

HEMTT storage area. 
Preliminary Assessment Report

Tulsa AASF #2 Tulsa, OK 

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 Tulsa AASF #2 (October 17, 2019) Tulsa, Oklahoma

Photograph No. 13

Description:

HEMTT fueling area with 

mobile fire extinguisher. 

Photograph No. 14

Description: 

Photo near the northwest part 

of the flightline. Photo is 

facing northwest, toward the 

drainage ditch where 

stormwater flows off the 

facility. 
Preliminary Assessment Report

Tulsa AASF #2 Tulsa, OK 

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 Tulsa AASF #2 (October 17, 2019) Tulsa, Oklahoma

Photograph No. 15

Description:

Ditch along the east side of the 

flightline. 

Photograph No. 16

Description: 

Photo facing west. Drainage 

from the OWS to Mingo 

Creek. 
Preliminary Assessment Report

Tulsa AASF #2 Tulsa, OK 

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 Tulsa AASF #2 (October 17, 2019) Tulsa, Oklahoma

Photograph No. 17

Description:

Photo facing east. Photo of 

historic Tri-MaxTM Training 

Area 3, which is located on 

the western flight line. 

Photograph No. 18

Description:

Photo facing northeast of 

location of historic Tri-MaxTM

Training Area 2. 
Preliminary Assessment Report

Tulsa AASF #2 Tulsa, OK 

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 Tulsa AASF #2 (October 17, 2019) Tulsa, Oklahoma

Photograph No. 19

Description:

Historic firetruck location, 

facing south. 

Photograph No. 20

Description:

Trench drain along west side 

of Storage Hangar and 

Maintenance Hangar. 
Preliminary Assessment Report

Tulsa AASF #2 Tulsa, OK 

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 Tulsa AASF #2 (October 17, 2019) Tulsa, Oklahoma

Photograph No. 21

Description:

36-gallon AFFF tank (built in 

2013) for manual fire fighting

in the hangars. Three of these 

tanks located in the Storage 

Hangar, and two are located in 

the Maintenance Hangar. 

Photograph No. 22

Description:

Chemical data information 

listed on the two 300-gallon 

AFFF tanks located in the 

Storage Hangar.