FINAL

Preliminary Assessment Report

Hilo Army Aviation Support Facility 

#2, Hawai‘i, Hawai‘i

Perfluorooctanesulfonic acid (PFOS) and 

Perfluorooctanoic acid (PFOA) at Impacted Sites

ARNG Installations, Nationwide

September 2020

Prepared for:

Army National Guard Bureau

111 S. George Mason Drive

Arlington, VA 22204

UNCLASSIFIED
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Table of Contents

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

1. Introduction...................................................................................................................... 3

1.1 Authority and Purpose.......................................................................................... 3

1.2 Preliminary Assessment Methods ........................................................................ 3

1.3 Report Organization ............................................................................................. 4

1.4 Facility Location and Description .......................................................................... 4

1.5 Facility Environmental Setting .............................................................................. 4

1.5.1 Geology ............................................................................................................... 5

1.5.2 Hydrogeology ....................................................................................................... 5

1.5.3 Hydrology............................................................................................................. 5

1.5.4 Climate ................................................................................................................ 6

1.5.5 Current and Future Land Use............................................................................... 6

2. Fire Training Areas ........................................................................................................ 10

3. Non-Fire Training Areas ................................................................................................. 11

3.1 Helicopter Parking Area ..................................................................................... 11

3.2 AASF Old Hangar .............................................................................................. 11

3.3 AASF New Hangar ............................................................................................. 11

4. Emergency Response Areas ......................................................................................... 13

5. Adjacent Sources .......................................................................................................... 14

5.1 Hilo International Airport ..................................................................................... 14

6. Preliminary Conceptual Site Model ................................................................................ 16

7. Conclusions ................................................................................................................... 17

7.1 Findings ............................................................................................................. 17

7.2 Uncertainties ...................................................................................................... 17

7.3 Potential Future Actions ..................................................................................... 18

8. References .................................................................................................................... 20
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Figures

Figure ES-1 Summary of Findings

Figure 1-1 Facility Location

Figure 1-2 Groundwater Features

Figure 1-3 Surface Water Features

Figure 3-1 Non-Fire Training Areas

Figure 5-1 Adjacent Source

Figure 7-1 Summary of Findings

Tables

Table 7-1 Summary of Uncertainties

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
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Acronyms and Abbreviations

°F degrees Fahrenheit

AASF Army Aviation Support Facility

AECOM AECOM Technical Services, Inc.

AFFF aqueous film forming foam

amsl above mean sea level

AOI area of interest

ARNG Army National Guard

bgs below ground surface

CERCLA Comprehensive Environmental Response, Compensation, and Liability

Act

CFR Code of Federal Regulations

CSM conceptual site model

DLNR Hawai‘i Department of Land and Natural Resources

DoD Department of Defense

EDRTM Environmental Data Resources, Inc.TM

FTA fire training area

HA Health Advisory

HIARNG Hawai‘i Army National Guard

KMR Keaukaha Military Reservation

MGD million gallons per day

PA Preliminary Assessment

PFAS per- and poly-fluoroalkyl 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

USFWS United States Fish and Wildlife Services

VSI visual site inspection
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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 Hilo Army Aviation Support Facility (AASF) #2

(also referred to as the “facility”) in Hilo, Hawai‘i, Hawai‘i to assess potential PFAS release areas

and exposure pathways to receptors. Occupation of the property by Hawai‘i ARNG began in 1952.

The performance of this PA included the following tasks:

· Reviewed available administrative record documents and Environmental Data Resources,

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

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

environmental compliance actions in the area surrounding the facility;

· Conducted a site visit on 29 April 2019 and completed visual site inspections at locations

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

· Interviewed current Hilo AASF #2 personnel, such as the Facility Manager, during the site

visit.

No known or documented releases of PFAS to the environment were identified at the facility during

the preparation of this PA report. Hilo International Airport was identified as an adjacent source of

PFAS, because eight major air incidents have occurred at the airport. At one of the incidents in

the early 1990s, Hilo AASF #2 personnel indicated that they assisted with the response using

water and Halon extinguishers (non-aqueous film forming foam [AFFF]). The response actions,

location, and extinguishing agents used (if any) are generally unknown for the other incidents

(Hawaii.gov, 2020).

Based on the PA findings regarding the historical use, storage or disposal of aqueous film forming

foam at the facility, there is no potential for exposure to PFAS contamination in soil, groundwater,

surface water, and sediment (Figure ES-1). Based on the United States (US) Environmental

Protection Agency (USEPA) Unregulated Contaminant Monitoring Rule 3 (UCMR3) data, it was

indicated that no PFAS were detected in a public water system above the USEPA’s lifetime Health

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.
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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 facilities that

used per- and poly-fluoroalkyl substances (PFAS) (a suite of related chemicals), primarily in the

form of aqueous film forming foam (AFFF) released as part of firefighting activities, although other

PFAS sources are possible. In addition, the ARNG is assessing businesses or operations adjacent

to the ARNG facility (not under the control of ARNG) that could potentially be responsible for a

PFAS release.

PFAS are classified as emerging environmental contaminants that are garnering increasing

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

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

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

continues to evolve. The US Environmental Protection Agency (USEPA) issued a lifetime Drinking

Water Health Advisory (HA) for PFOA and PFOS in May 2016, but there are currently no

promulgated national standards regulating PFAS in drinking water. The HA is 70 parts per trillion

for PFOS and PFOA, individually or combined.

This report presents findings of a PA for PFAS at Hilo Army Aviation Support Facility (AASF) #2

(also referred to as the “facility”) in Hilo, Hawaiʻi, Hawaiʻi in accordance with the Comprehensive

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

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

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

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

Hilo 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 site visit on 29 April 2019 and completed visual site inspections (VSIs) at

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

disposed; 

· Interviewed current Hilo AASF #2 personnel, such as the Facility Manager, during the site

visit.
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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 as follows:

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

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

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

identified during the site visit.

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

at the facility identified during the site visit.

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

facility, specifically in response to emergency situations.

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

facility that are not under the control of ARNG.

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

transport and receptors at the facility.

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

uncertainties 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

Hilo AASF #2 is an 8-acre parcel located on Lyman Field northwest of Keaukaha Military

Reservation (KMR) and south of Hilo Bay. The facility is surrounded by Hilo International Airport

on three sides, with a forested area to the south (Figure 1-1).

The Hawaiʻi ARNG (HIARNG) acquired the property in 1952 as part of an Executive Order. Hilo

AASF #2 provides training and maintenance for one aviation unit that supports the HIARNG. The

facility consists of office areas, hangars, and an aircraft parking area. In order to support an

aviation team, AASF #2 was renovated and expanded. The expansion included the construction

of a new, larger hangar adjacent to the older hangar (Department of Defense [DoD], 2015; 

Appendix A).

1.5 Facility Environmental Setting

Hilo AASF #2 is located on the eastern flanks of the Mauna Kea and Mauna Loa volcanoes, where

the topography gently slopes down from the mountains to the ocean due to the repeated

outpouring of highly fluid lavas from fissures along rift zones. Hilo AASF #2 is approximately 2

miles from the Pacific Ocean, in a relatively flat, low-lying area composed of gently rolling terrain.

Hilo’s elevation is only 38 feet above mean sea level (amsl) (Hawaiian Island Chamber of

Commerce, 2003).
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1.5.1 Geology

Located at the southwestern end of the Hawaiian Archipelago, the Island of Hawaiʻi is the

youngest of the Hawaiian Islands. Hualālai, Mauna Loa, and Kīlauea are the only active volcanoes

on the island of Hawaiʻi. Typically, these volcanoes are made up of thousands of individual basalt

flows, which are occasionally separated by tuff or pyroclastic debris (Inter Island Environmental

Services, Inc., 1997).

Hilo AASF #2 lies on basaltic lava flows representative of the Mauna Loa volcanic series. These

lava flows are known as the Kau Volcanics, which range in age from recent to late Pleistocene.

Underlying the Kau Volcanics are the Pahala Ash, the Kahuku Basalt, and the Nīnole Volcanics,

all of which erupted from Mauna Loa (Inter Island Environmental Services, Inc., 1997). The basalt

flows are generally thinly bedded pahoehoe near the summit that transition to a‘a as the lava

becomes more viscous downslope.

1.5.2 Hydrogeology

The basalt flows underlying Hilo AASF #2 are highly permeable, making extensive aquifers (Inter

Island Environmental Services, Inc., 1997). Hilo AASF#2 sits above the Northeast Mauna Loa

aquifer sector on the boundary of two different aquifer systems, the Hilo system and the Keaʻau

system (Figure 1-2). The Hilo system, in the northwest portion of the Mauna Loa aquifer sector,

has a sustainable yield of approximately 347 million gallons per day (MGD). The Keaʻau system,

in the southeast portion of the Mauna Loa aquifer sector, has a sustainable yield of approximately

393 MGD (Mitchell et al., 2005)). The Mauna Loa aquifer sector is used as a potable water source

because groundwater occurs as a basal lens of freshwater sitting atop intruding saltwater (Inter

Island Environmental Services, Inc., 1997). Although the exact groundwater flow direction is

unknown, it is assumed to mimic topography and flow north-northeast toward the ocean (Figure

1-2).

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

A). Using additional online resources, such as state and local Geographic Information System

databases, wells were researched to a 4-mile radius of the facility. Prior to the 1950s, there were

two wells (Well 1 and Well 2) that were used as Hilo AASF #2’s water supply. Well 1 was located

on HIARNG property and drilled to a depth of 76 feet below ground surface (bgs). Well 2 was

located on DLNR land and drilled to a depth of 87 feet bgs. Water levels in the wells were

measured at 4 and 5 feet amsl, respectively. Both wells were decommissioned in the 1950s, and

drinking water for Hilo AASF #2 is currently supplied from groundwater resources located in

Panaʻewa, approximately 3 miles southwest (upgradient) of Hilo AASF #2.

Based on the USEPA’s Unregulated Contaminant Monitoring Rule 3 (UCMR3) data, it was

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

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

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

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

the UCMR3 but might be detected if analyzed today.

1.5.3 Hydrology

Despite the large amount of rainfall in Hilo, there are no perennial streams and no well-defined

drainages in the immediate vicinity of Hilo AASF #2 due to the porous nature of the underlying

basalt flows (Inter Island Environmental Services, Inc., 1997). Although there are no surface water

bodies on Hilo AASF #2, there are several close to the facility. Lokoaka Pond is approximately 1.5

miles north of the facility and is considered a freshwater wetland that is susceptible to seasonal

flooding. Lokoaka Pond is adjacent to Kionakapahu Pond, a freshwater wetland that is
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permanently flooded (US Fish and Wildlife Services [USFWS], 2019). Both wetlands are partially

fed by groundwater and partially by rainwater.

In addition to Lokoaka Pond and Kionakapahu Pond, three unnamed estuarine wetlands are

located inland along the coastline from Hilo Bay to Leleiwi Point approximately 1.6 to 2.5 miles

northeast of the facility (USFWS, 2019). There are also eight lava anchialine ponds, located along

the coast between Keokea Point and Leleiwi Point and between Leleiwi Point and Papaʻi Bay,

downgradient of the facility (Figure 1-3). The anchialine ponds vary from brackish to saline, are

fed by groundwater, are connected to the ocean by lava tubes, and are affected by tidal variations

(Mitchell et al., 2005).

1.5.4 Climate

Hilo AASF #2 is located in Hilo, on the eastern side of the Island of Hawaiʻi. The average annual

precipitation at Hilo AASF #2 is 126.7 inches, and the precipitation is well-distributed throughout

the year. The temperatures are mild and have little variation throughout the year. The average

annual low is 66.8 degrees Fahrenheit (oF) and the average annual high is 80.9 oF. On average,

the highest temperatures occur in August and September, while January and February tend to be

the coolest months (National Oceanic and Atmospheric Administration, 2018).

1.5.5 Current and Future Land Use

Current Hilo AASF #2 operations include training and maintenance command for the aviation unit,

which support the HIARNG. The facility shares tarmac space with the neighboring Hilo

International Airport to the north.

A forested area demarcates the southern boundary of the facility and lies between the facility,

KMR, and an industrial area. The nearest residential homes are located approximately 0.5 miles

northeast and 1 mile west from the Hilo AASF #2.

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

described above.
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Facility Location

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Groundwater Features

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2. Fire Training Areas

There are no FTAs located within Hilo AASF #2. There is a fire training building used by the

municipal fire department on KMR. It was built in 2016 and is not considered to be a potential

source of PFAS, as only water is used during training activities. Based on the interviewee’s

knowledge of facility history since the late 1980s, fire training did not occur at the Hilo AASF #2.
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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. Three non-FTAs were

identified during the PA. A description of each non-FTA is presented below, and the non-FTAs are

shown on Figure 3-1. Photographs of each non-FTA appear in Appendix C.

3.1 Helicopter Parking Area

The helicopter parking area is located north of the two Hilo AASF #2 hangars. Adjacent to each

of the helicopters is a Halon (non-AFFF) fire extinguisher. There are no AFFF fire extinguishers

present within the parking area. According to the interviewee, the tarmac and parking area

pavement was replaced in 2000. The helicopter parking area is not considered a suspected PFAS

release area due to the lack of AFFF storage and use.

3.2 AASF Old Hangar

The Old Hangar was built in 1983 and is used as a maintenance hangar. The Old Hangar stores

various maintenance-related chemicals but contains no AFFF according to the interview with the

Hilo AASF #2 personnel and confirmed during the VSI. The fire suppression system within the

building is a water sprinkler system. The Old Hangar is not considered a suspected PFAS release

area due to the lack of AFFF storage and use.

3.3 AASF New Hangar

The New Hangar was built around 2000 for helicopter maintenance use. The New Hangar is

located adjacent to the Old Hangar and stores maintenance-related chemicals and solvents but

contains no AFFF according to interviews with the Hilo AASF #2 personnel and confirmed during

the VSI. The fire suppression system is a water sprinkler system. A trench drain is located near

the hangar door. According to the interviewee, the trench drain is used to prevent water from the

outside getting into the hangar. The trench drain is connected to the storm water drain. The New

Hangar is not considered a suspected PFAS release area due to the lack of AFFF storage and

use.
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4. Emergency Response Areas

No instances of emergency responses were identified at Hilo AASF #2 during the PA based on

interviews. The facility relies on the local fire department or the nearby federal fire department for

emergency needs. There has been no need for response as to date of the PA interviews.

Interviewees highlighted their history of zero incidents at the facility (Appendix B.1).
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5. Adjacent Sources

One potential off-facility source of PFAS adjacent to Hilo AASF #2, not under the control of the

HIARNG, was identified during the PA. A description of the adjacent source is presented below,

and the adjacent source is shown on Figure 5-1.

5.1 Hilo International Airport

According to the interviewee, in the early 1990s, an emergency response was conducted on a

private plane crash at the Hilo International Airport. During the response action, the personnel at

the Hilo AASF #2 used water and a green fire extinguisher to put out the fire on the plane. The

interviewee suggested that the extinguisher contained Halon (non-AFFF). Eight major air

incidents, some of which have resulted in fire, have occurred at Hilo International Airport between

1957 and 2000 (Hawaii.gov, 2020). The response actions, exact location of the incidents, and

extinguishing agents used are unknown, but the airport’s crash rescue team is the first responder.

Hilo International Airport personnel were not interviewed during the PA because they were

unavailable at the time of the PA. Therefore, it is not known if AFFF is or were used or stored at

the airport currently or historically. Because the presence of AFFF at the airport cannot be

confirmed, and multiple major air incidents have occurred, Hilo International Airport has been

identified as a potential off-facility PFAS source area. Figure 5-1 shows the location of Hilo

International Airport (as a potential PFAS source area) in relation to the Hilo AASF#2.
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Base Map: Source: Esri, DigitalGlobe, GeoEye,

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

C:\Users\stankevichm\OneDrive - AECOM Directory\ARNG_PFAS_GIS_60552172\MXDs\HI\Hilo_AASF2_Figures\Fig_5-1_Hillo_AASF2_Adjacent.mxd

0 1,000 2,000 4,000

Feet

Legend

Potential PFAS Release

Facility Boundary

Water Body

River/Stream

15
PFAS Preliminary Assessment Report

Hilo AASF #2, Hawaiʻi, Hawaiʻi

16

6. Preliminary Conceptual Site Model

Based on the PA findings, no release areas were identified as areas of interest (AOIs); therefore, 

a preliminary conceptual site model (CSM) is not required for the facility. A CSM identifies three

components necessary for potentially complete exposure pathways: (1) source, (2) pathway, and

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

on the findings of this PA, there are no PFAS sources at Hilo AASF #2; thus, there is no complete

exposure pathway to potential receptors from ARNG use of the facility.
PFAS Preliminary Assessment Report

Hilo AASF #2, Hawaiʻi, Hawaiʻi

17

7. Conclusions

This report presents a summary of available information gathered during the PA on PFAS-related

activities at Hilo AASF #2. The PA findings are based on the information presented in Appendix

A and Appendix B.

7.1 Findings

No known or documented releases of PFAS to the environment were identified during PA activities

at the Hilo AASF #2 facility. In addition, no AFFF is known to have ever been stored or disposed

of at the facility, either historically or at the time of the PA. Therefore, there is no potential for

exposure to PFAS contamination in soil, and groundwater from onsite sources. Figure 7-1

presents a summary of the PA findings.

7.2 Uncertainties

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

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

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

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

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

The conclusions of this PA are predominantly based on the information (or lack thereof) provided

during interviews with personnel who had direct knowledge of PFAS use at the facility. 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. Comprehensive information on all industrial practices that may potentially be

sources of PFAS is incomplete. Therefore, this PA may not identify all potential PFAS sources.

In order to minimize the level of uncertainty, readily available data regarding the historical 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.

Inherent uncertainty is associated with information regarding potential releases at adjacent

sources because direct knowledge regarding PFAS-related activities at the Hilo International

Airport is not known. Interviews were not conducted with Hilo International Airport staff, and the

site visit did not include visiting municipal airport assets and hangars because the focus of the

assessment was to evaluate potential PFAS related activities and sources at HIARNG properties,

not formally assess adjacent sources. AFFF storage or use is commonly associated with such

municipal airport facilities.

The following table (Table 7-1) summarizes the uncertainties associated with the PA:
PFAS Preliminary Assessment Report

Hilo AASF #2, Hawaiʻi, Hawaiʻi

18

Table 7-1: Summary of Uncertainties

Location Source of Uncertainty

Old and New

Hangars

During the interview process, a limited number of personnel were

available to be interviewed. Additionally, their tenure at Hilo AASF #2

dates back to 1989. The use and storage of AFFF at the Hilo AASF

#2 between 1969 and 1989 are unknown.

Hilo International

Airport (Potential

Adjacent Source)

The use and storage of AFFF at the Hilo International Airport are

unknown. Eight major air incidents have occurred at the airport, but

the response actions, location, and extinguishing agents used (if any)

are unknown for each incident (Hawaii.gov, 2020). No interviews were

conducted for the off-facility area.

7.3 Potential Future Actions

Based on the documented absence (1989 to present) of the use, storage or disposal of PFAScontaining materials at Hilo AASF #2, no AOIs were identified during the PA. No evidence was

found to indicate that current or former ARNG activities contributed to PFAS contamination in soil,

groundwater, surface water, or sediment at the facility or adjacent areas. Hilo AASF #2 will not

move forward in the CERCLA process.
Pacific

Ocean

Hilo

International

Airport

Helicopter

Parking Area

New Hangar

Old Hangar

CLIENT

REVISED

SCALE

ARNG

GIS BY

CHK BY

MS

CR

6/1/2020

6/1/2020

Preliminary Assessment for PFAS at Hilo AASF #2, HI

6/1/2020

1:24,000 ­ Figure 7-1 PM RG 6/1/2020

12420 Milestone Center Drive

Germantown, MD 20876

Summary of Findings

Base Map: Source: Esri, DigitalGlobe, GeoEye,

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

C:\Users\stankevichm\OneDrive - AECOM Directory\ARNG_PFAS_GIS_60552172\MXDs\HI\Hilo_AASF2_Figures\Fig_7-1_Hillo_AASF2_Summary.mxd

0 1,000 2,000 4,000

Feet

Legend

Potential PFAS Release

No Suspected Release

Facility Boundary

Water Body

River/Stream

19
PFAS Preliminary Assessment Report

Hilo AASF #2, Hawaiʻi, Hawaiʻi

20

8. References

Hawaii.gov. 2020. Hawaii Aviation: An Archive of Historic Photos and Facts.

https://aviation.hawaii.gov/major-air-incidents/hilo-international-airport/ (Accessed 7

August 2020).

Hawaiian Island Chamber of Commerce. 2003. Hawai‘i’s History. http://www.gohilo.com/hawaii/.

(Accessed 13 July 2006).

Inter Island Environmental Services, Inc. 1997. Preliminary Assessment at Keaukaha Military

Reservation Hilo, Hawaiʻi. April.

Mitchell, C. et al. 2005. Hawaiʻi’s Comprehensive Wildlife Strategy. Honolulu, Hawai‘i: Department

of Land and Natural Resources (DLNR). October. 722 pages.

National Oceanic and Atmospheric Administration. 2018. Monthly Climate Normals (1981-2010)

– Hilo Area, HI (ThreadEx). https://w2.weather.gov/climate/xmacis.php?wfo=hnl.

(Accessed 12 August 2020).

State of Hawaiʻi, Department of Defense (DoD). 2015. Final Draft Integrated Cultural Resources

Management Plan Update for Sites and Training Installations of the Hawaiʻi Army National

Guard, Fiscal Years 2016-2021. Prepared by Search. September.

USEPA. 1991. Guidance for Performing Preliminary Assessments Under CERCLA. EPA/540/G91/013. September 1991.

United States Fish and Wildlife Services (USFWS). 2019. USFWS National Wetlands Inventory

Wetlands Mapper https://www.fws.gov/wetlands/data/mapper.html (Accessed 15 June

2019).
PFAS Preliminary Assessment Report

Hilo AASF #2, Hawaiʻi, Hawaiʻi

Appendix A

Data Resources
PFAS Preliminary Assessment Report

Hilo AASF#2, Hawai’i, Hawai’i

Data Resources will be provided separately on CD. Data Resources for Hilo AASF #2, Hawai’i 

include:

Hilo AASF #2 EDRTM Report

• 2019 EDRTM Aerial Photo Decade Package

• 2019 EDRTM Radius Map Report with GeoCheck

• 2019 Certified Sanborn Map Report

Hilo AASF #2 Underground Injection Control Line

• UIC Line for Pearl City

Hilo AASF #2 Environmental Reports

• 1996 Environmental Assessment of the Hawaii Army National Guard Limited Army Aviation

Facility

• 2015 Integrated Cultural Resources Management Plan Update for Sites and Training

Installations of Hawaii Army National Guard
PFAS Preliminary Assessment Report

Hilo AASF #2, Hawaiʻi, Hawaiʻi

Appendix B

Preliminary Assessment Documentation
PFAS Preliminary Assessment Report

Hilo AASF #2, Hawaiʻi, Hawaiʻi

Appendix B.1

Interview Records

PFAS Preliminary Assessment Report

Hilo AASF #2, Hawaiʻi, Hawaiʻi

Appendix B.2

Visual Site Inspection Checklists


PFAS Preliminary Assessment Report

Hilo AASF #2, Hawaiʻi, Hawaiʻi

Appendix B.3

Conceptual Site Model Information



PFAS Preliminary Assessment Report

Hilo AASF #2, Hawaiʻi, Hawaiʻi

Appendix C

Photographic Log
Preliminary Assessment Report

Hilo AASF #2

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 Hilo AASF #2 Hawai’i

Photograph No. 1

Description:

The new paved tarmac against 

the old.

Date Taken:

29 April 2019

Photograph No. 2

Description:

The helicopter parking area 

and the area where a private 

plane caught fire in the early 

1990s.

Date Taken:

29 April 2019
Preliminary Assessment Report

Hilo AASF #2

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 Hilo AASF #2 Hawai’i

Photograph No. 3

Description:

Halon fire extinguisher in Old 

Hangar.

Date Taken:

29 April 2019

Photograph No. 4

Description: 

Fire extinguishers in 

helicopter parking area.

Date Taken:

29 April 2019
Preliminary Assessment Report

Hilo AASF #2

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 Hilo AASF #2 Hawai’i

Photograph No. 5

Description:

Old hangar

Date Taken:

29 April 2019

Photograph No. 6

Description:

Air and water canisters in 

New Hangar.

Date Taken:

29 April 2019
Preliminary Assessment Report

Hilo AASF #2

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 Hilo AASF #2 Hawai’i

Photograph No. 7

Description:

Drain located in New Hangar. 

Used to prevent water from 

coming into the hangar.

Date Taken:

29 April 2019

Photograph No. 8

Description:

New hangar.

Date Taken:

29 April 2019
Preliminary Assessment Report

Hilo AASF #2

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 Hilo AASF #2 Hawai’i

Photograph No. 9

Description: 

New Hangar (left) next to the 

Old Hangar (right)

Date Taken:

29 April 2019