PB98-964012
EPA 541-R98-058
October 1998
EPA Superfund
Record of Decision:
Cecil Field Naval Air Station OU 8
Jacksonville, FL
8/27/1998
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Record Of
Site 3, Operable Unit 8
for
Naval Air Station
Jacksonville, Florida
Southern Division
Naval Facilities Engineering Command
Contract Number N62467-94-D-0888
Contract Task Order 039
September 1998
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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION 4
ATLANTA FEDERAL CENTER
61 FORSYTH STREET, SW
ATLANTA, GEORGIA30303-8909
SEP 2 9 «».
CERTIFIED MAIL
RETURN RECEIPT REQUESTED
4WD-FFB
Commanding Officer
Attn.: David Porter
Base Environmental Coordinator
DON, Southern Division
Naval Facilities Engineering Command
Mail Code 18B2
P.O. Box 190010
North Charleston,
South Carolina 20419-9010
Subject: Naval Air Station Cecil Field, Jacksonville, Florida
Record of Decision for Operable Unit 5, site 14
Dear Mr. Porter:
The Environmental Protection Agency (EPA) has received and reviewed the final Record
of Decision (ROD) for Operable Unit 5 (OU 5), site 14. EPA concurs with the Navy's decision
as set forth in the ROD dated July 1998. This concurrence is contingent with the understanding
that the selection of no further remedial action at this site is protective of human health and the
environment. Should new information indicate otherwise, the Navy is liable for any future
actions as required.
NAS Cecil Field was listed on the National Priorities List as Cecil Field Naval Air
Station in 1989. Prior to NPL listing and designation for closure, the Installation and
Restoration Program identified 18 sites as needing further investigation. These 18 sites were
grouped by usage and waste type to form eight operable units. OU 5 consists of sites 14 and 15,
which were both used for ordnance demolition. This Record of Decision addresses only site 14.
Site 14 is located in an area designated for forestry management and recreation per the NAS
Cecil Field Final Reuse Plan, dated February 1996. Development of groundwater resources and
construction of buildings at this location is not anticipated. The Remedial Investigation and
Risk Assessment for OU 5, site 14 identified no unacceptable risks for any media, therefore no
further action is being recommended at this time. However, any new information contradicting
this finding may require further investigation or remedial actions.
R0cycl«d/R«cyctaM« • Printed with Vegetable Oil Based Inks on 100% Recycled Paper (40% Postconsumer)
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EPA appreciates the coordination efforts of NAS Cecil Field and the level of effort that
was put forth in the documents leading to this decision. EPA looks forward to continuing the
excellent working relationship with NAS Cecil Field and Southern Division Naval Facilities
Engineering Command as we move toward final cleanup of the NPL site. Should you have any
questions, or if EPA can be of any further assistance, please contact Ms. Deborah Vaughn-
Wright, of my staff, at the letterhead address or at (404) 562-8539.
Sincerely,
Richard D. Green
Director
Waste Management Division
cc: Mr. James Crane, FL DEP
Mr. Eric Nuzie, FL DEP
Mr. Michael Deliz, FL DEP
Mr. Mark Davidson, SOUTHDIV
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049811 IP
RECORD OF DECISION
SITE 3, OPERABLE UNIT 8
FOR
NAVAL AIR STATION CECIL FIELD
JACKSONVILLE, FLORIDA
COMPREHENSIVE LONG-TERM
ENVIRONMENTAL ACTION NAVY (CLEAN) CONTRACT
Submitted to:
Southern Division
Naval Facilities Engineering Command
2155 Eagle Drive
North Charleston, South Carolina 29406
Submitted by:
Brown & Root Environmental
661 Andersen Drive
Foster Plaza 7
Pittsburgh, Pennsylvania 15220
CONTRACT NUMBER N62467-94-D-0888
CONTRACT TASK ORDER 039
SEPTEMBER 1998
PREPARED BY:
APPROVED FOR SUBMITTAL BY:
C/lxt^xyi^VH
,P.E. Q
MARK SPERAf
TASK ORDER MANAGER
BROWN & ROOT ENVIRONMENTAL
PITTSBURGH, PENNSYLVANIA
EBBIE WROBLEWSKI
PROGRAM MANAGER
BROWN & ROOT ENVIRONMENTAL
PITTSBURGH, PENNSYLVANIA
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TABLE OF CONTENTS
SECTION PAGE NO.
ACRONYM LIST iv
1.0 INTRODUCTION 1-1
1.1 SITE NAME AND LOCATION 1-1
1.2 STATEMENT OF BASIS AND PURPOSE 1-1
1.3 ASSESSMENT OF THE SITE 1-1
1.4 DESCRIPTION OF THE SELECTED REMEDY 1-1
1.5 STATUTORY DETERMINATIONS 1-2
1.6 SIGNATURE AND SUPPORT AGENCY ACCEPTANCE OF REMEDY 1-3
2.0 DECISION SUMMARY 2-1
2.1 SITE NAME, LOCATION, AND DESCRIPTION 2-1
2.2 SITE HISTORY AND ENFORCEMENT ACTIVITIES 2-4
2.3 HIGHLIGHTS OF COMMUNITY PARTICIPATION 2-6
2.4 SCOPE AND ROLE OF OPERABLE UNIT 2-6
2.5 SUMMARY OF SITE CHARACTERISTICS 2-7
2.5.1 Hydrogeology 2-7
2.5.2 Contaminant Sources 2-8
2.6 SUMMARY OF SITE RISKS 2-27
2.6.1 Human Health Risk Assessment 2-27
2.6.2 Ecological Risk Assessment 2-29
2.7 DESCRIPTION OF REMEDIAL ALTERNATIVES 2-31
2.7.1 Available Remedial Alternatives 2-31
2.7.2 Groundwater Remedial Alternatives for Operable Unit 8, Site 3 2-31
2.8 SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES 2-37
2.9 SELECTED REMEDY : 2-37
2.10 STATUTORY DETERMINATIONS 2-41
2.11 DOCUMENTATION OF SIGNIFICANT CHANGES 2-41
REFERENCES R-1
049811/P jj CTO0039
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TABLES
NUMBER PAGE NO.
2-1 Human Health Risk Summary 2-28
2*2 Summary of Risk Characterization for Wildlife, Plant, and Invertebrate Receptors, Site 3 2-30
2-3 Explanation of Evaluation Criteria 2-38
2-4 Comparison of Groundwater Cleanup Alternatives 2-39
2-5 Synopsis of Federal and State Regulatory Requirements for OU8, Site 3 2-42
FIGURES
NUMBER PAGE NO.
2-1 General Location Map 2-2
2-2 Site Location Map 2-3
2-3 Surface Soil Screening Locations 2-11
2-4 Subsurface Soil and Groundwater Screening Locations 2-13
2-5 Confirmatory Surface and Subsurface soil, sediment, surface water and 2-15
monitoring well sampling locations
2-6 TCE, TRPH. and Total VOCs in Surface and Subsurface Soil 2-17
2-7 Organics in the Surficial Aquifier 2-23
049811/P jjj CTO0039
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ACRONYM LIST
ABB-ES ABB Environmental. Inc.
AIMD Aircraft Intermediate Maintenance Department
ARAR Applicable or Relevant and Appropriate Requirements
bis below land surface
BRA Baseline Risk Assessment
B & R Brown & Root
BRAC Base Realignment and Closure
CA Contamination Assessment
CERCLA Comprehensive Environmental Response, Compensation, and Liability Act
COPC Chemical of Potential Concern
DCB Dichlorobenzene
DCE Dichloroethene
EBS Environmental Baseline Survey
ELCR Excess Lifetime Cancer Risk
ERA Ecological Risk Assessment
FDEP Florida Department of Environmental Protection
FFA Federal Facility Agreement
FS Feasibility Study
ft/ft feet per foot
ft/yr feet per year
GAC Granular Activated Carbon
HI Hazard Index
HQ Hazard Quotient '
IR Installation Restoration
IAS Initial Assessment Study.
IZS Intermediate Zones
K Hydraulic Conductivity
LZS Lower Zones
MCL Maximum Contaminant Level
mg/kg milligram per kilogram
NACIP Naval Assessment and Control of Installation Pollutants
NAS Naval Air Station
NCP National Oil and Hazardous Substances Pollution Contingency Plan
049811/P
IV
CTO 0039
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NPL National Priority List
OU Operable Unit
PCB Polychlorinated biphenyl
PSC potential source of contamination
RA Remedial Action
RAB Restoration Advisory Board
RBC Risk-Based Concentration
RCRA Resource Conservation and Recovery Act
RAO Remedial Action Objective
RFI RCRA Facility Investigation
RI/FS Remedial Investigation/Feasibility Study
ROD Record of Decision
SARA Superfund Amendments and Reauthorization Act
SVOC Semivolatile Organic Compound
TCE Trichloroethene
TRPH Total Recoverable Petroleum Hydrocarbon
ug/kg microgram per kilogram
ug/L microgram per liter
U.S. EPA U.S. Environmental Protection Agency
USGS U. S. Geological Survey
UST Underground Storage Tank
UZH Upper Zone of the Hawthorn
UZS Upper Zones
VOC Volatile Organic Compound
049811/P
CTO 0039
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1.0 DECLARATION OF THE RECORD OF DECISION
1.1 SITE NAME AND LOCATION
Operable Unit (OU) 8 consists of Site 3, the Oil and Sludge Disposal Pit and affected area (Figure 2-1).
The site is situated in the western part of the main base of Naval Air Station (NAS) Cecil Field,
Jacksonville, Florida, immediately northeast of the intersection of Perimeter Road and the Lake Fretwell
access road leading west from the south end of Lake Fretwell.
1.2 STATEMENT OF BASIS AND PURPOSE
This decision document presents the selected remedial action for Site 3 at NAS Cecil Field. The remedial
action was chosen in accordance with the Comprehensive Environmental Response, Compensation, and
Liability Act (CERCLA), as amended by the Superfund Amendments and Reauthorization Act (SARA) of
1986, and the National Oil and Hazardous Substances Pollution Contingency Plan (NCP) (40 Code of
Federal Regulations 300). This decision document was prepared in accordance with the U.S.
Environmental Protection Agency (U.S. EPA) decision document guidance (U.S. EPA, 1992). This
decision is based on the Administrative Record for Site 3, OU 8.
The U.S. EPA and the State of Florida concur with the selected remedy.
1.3 ASSESSMENT OF THE SITE
Actual or threatened releases of hazardous substances from this site, if not addressed by implementing
the response actions selected in this Record of Decision (ROD), may present an imminent and substantial
endangerment to public health, welfare, or thb environment. Unacceptable human health risks would exist
if groundwater from the surficial aquifer is used as a potable water source. Human health and possibly
wildlife may incur unacceptable risks if exposed to undiluted Site 3 groundwater. There may also be an
unacceptable risk to human health from exposure to surface soil and sediment under a future residential
scenario.
1.4 DESCRIPTION OF THE SELECTED REMEDY
This ROD is the final action for Site 3, OU 8. Final RODs have been approved for OUs 1, 2, 4, and 7.
Remedial Investigations (RIs) and Baseline Risk Assessments (BRAs) have been completed for OUs 5, 6,
and 8.
049811/P 1-1 CTO0039
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The selected remedy addresses contaminant reduction in groundwater at the site. Remedial alternatives
selected for Site 3 include groundwater treatment and monitoring, and the implementation of site controls.
The major components of the selected remedy are as follows:
• In-situ subsurface volatilization, also referred to as air sparging, will be used to remove volatile organic
compounds (VOCs) from groundwater in the source area. Pilot studies will be implemented prior to
final design to ensure the proper performance of the system. A monitoring plan will be implemented to
monitor and evaluate the effectiveness of the air sparging system.
• Following air sparging, long-term sampling and analysis of groundwater will monitor the decrease in
contaminant concentrations resulting from natural processes until acceptable levels have been
reached.
• Implementation of institutional controls, including deed restrictions, will limit use of contaminated
groundwater until natural processes reduce contaminant concentrations to acceptable levels, and will
restrict future site uses. Industrial, commercial, and recreational uses are allowed. Residential
(including housing, daycare, and schools) and agriculture uses are prohibited.
• Review of site conditions and groundwater monitoring data every 5 years will verify the effectiveness
of the remedy for the protection of human health and the environment.
1.5 STATUTORY DETERMINATIONS
The selected remedy is protective of human health and the environment, is cost effective, and complies
with Federal and State requirements that are legally applicable or relevant and appropriate to remedial
action. The nature of the selected remedy for Site 3 is such that, applicable or relevant and appropriate
requirements (ARARs) will be met in the long-term as residual concentration of contaminants in the
groundwater are reduced through natural attenuation. The remedy utilizes permanent solutions and
satisfies the statutory preferences for remedies that employ treatment to reduce toxicity, mobility, or
volume as a principal element. Because this remedy would result in hazardous substances remaining
onsite above health-based levels, a review will be conducted within 5 years of the commencement of
remedial actions to ensure that the remedy continues to provide adequate protection of human health.
049811/P 1-2 CTO0039
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1.6 SIGNATURE AND SUPPORT AGENCY ACCEPTANCE OF REMEDY
^^^-^•/y^
) ^
David L. Porter, P.E. Date
Base Realignment and Closure
Environmental Coordinator
049811/P 1-3 CT00039
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2.0 DECISION SUMMARY
2.1 SITE NAME, LOCATION, AND DESCRIPTION
As shown on Figure 2-1, NAS Cecil Field is 14 miles southwest of Jacksonville, Florida. Most of Cecil
Field is in Duval County; the southernmost part is in Clay County.
NAS Cecil Field was established in 1941 and provides facilities, services, and material support for the
operation and maintenance of naval weapons, aircraft, and other units of the operation forces as
designated by the Chief of Naval Operations. Some of the tasks required to accomplish this mission over
past years included operation of fuel storage facilities, performance of aircraft maintenance, maintenance
and operation of engine repair facilities and test cells for turbo-jet engines, and support of special weapons
systems.
NAS Cecil Field is scheduled for closure in 1999. Much of the facility will be transferred to the
Jacksonville Port Authority. The facility will have multiple uses, but will be used primarily for aviation-
related activities.
Land surrounding NAS Cecil Field is used primarily for forestry with some agriculture and ranching. Small
communities and individual homes are in the vicinity of NAS Cecil Field. The closest community, located
on Nathan Hale Road, abuts the western edge of the facility. The nearest incorporated municipality,
Baldwin, is approximately 6 miles northwest of the main facility entrance.
To the east of NAS Cecil Field, the rural surrounding area grades into a suburban fringe bordering the
major east- and west-roadways. Commercial properties, such as convenience stores, and low-density
residential areas characterize the land use (ABB Environmental, Inc. [ABB-ES], 1992). A development
called Villages of Argyle, when complete, will consist of seven separate villages that will border NAS Cecil
Field to the south and southeast. A golf course and residential area also border NAS Cecil Field to the
east (Southern Division, Naval Facilities Engineering Command [SOUTHNAVFACENGCOM], 1989).
As shown on Figure 2-2, OU8 is located near the western perimeter of NAS Cecil Field, in the flight path of
landing aircraft. It is a vacant, relatively featureless area with no residential, commercial, or industrial
functions. Human activity is generally limited to security patrols or joggers on the Lake Fretwell access
road and Perimeter Road. Vegetative cover consists of thick brush and briers. A disposal pit, estimated
to be approximately 100 feet in diameter and 3 to 5 feet deep, is located immediately northeast of the
intersection of Perimeter Road and the Lake Fretwell access road, both of which are unpaved. There is a
049811/P 2-1 CTO0039
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NOTES:
NAS = Naval Air Station
OLF = Outlying Landing Field
13.000
SCALE IN FEET
26.000
FIELD
NOT TO SCALE
DRAWN BY DATE
MF 4/24/98
CHECKED BY
DATE
COST/SCHED-AREA
I I i
SCALE
AS NOTED
GENERAL LOCATION MAP
RECORD OF DECISION
OPERABLE UNIT 6 SITE 3
NAVAL AIR STATION CECIL HELD
JACKSONVILLE. FLORIDA
CONTRACT NO.
7653
APPROVED BT
DATE
APPROVED BY
DATE
DRAWING NO.
FIGURE 2-1
REV.
0
rO»M CAOD NO. SDIV.AV.DVG - REV 0 - 1/80/98
049811/P
2-2
CTO0039
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ACAD: 0:/7653/7653em01.dwg 07/13/98 HP
2
8
ro
i
8
Note: Existing wells proposed for monitoring ore circled.
u f\ \-6-tool choln-llnl
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relatively uniform gentle slope toward Powell Creek and Lake Fretwell over the length of OU8. A 6.7-acre
wetland is located approximately 800 feet east of the disposal pit, adjacent to Rowell Creek. Rowell Creek
is classified by the state of Florida as Class III freshwater.
2.2 SITE HISTORY AND ENFORCEMENT ACTIVITIES
The first environmental study for the investigation of waste handling and/or disposal sites at NAS Cecil
Field was conducted between 1983 and 1985 by Geraghty & Miller, Inc (Geraghty and Miller, 1983). This
study was followed by an Initial Assessment Study (IAS) by Envirodyne Engineers in 1985 (Envirodyne
Engineers, 1985). The IAS was completed under the Naval Assessment and Control of Installation
Pollutants (NACIP) program, which was the precursor to the Navy's present Installation Restoration (IR)
program. In 1988, a Resource Conservation and Recovery Act (RCRA) Facility Investigation (RFI) was
completed by Harding Lawson Associates (Harding Lawson Associates, 1988). The RFI acted on the
recommendations of the IAS. OU8 (Site 3) was included in the IAS and the RFI.
NAS Cecil Field was placed on the National Priority List (NPL) by the U.S. EPA and the Office of
Management and Budget in December 1989. A Federal Facility Agreement (FFA) for NAS Cecil Field was
signed by the Florida Department of Environmental Protection (FDEP, formerly the Florida Department of
Environmental Regulation), U.S. EPA, and the Navy in 1990. Following the listing of NAS Cecil Field on
the NPL and the signing of the FFA, remedial response activities at the facility have been completed under
CERCLA authority. OU8 (Site 3) is one of eight operable units identified as needing further investigation.
NAS Cecil Field has several sites where hazardous wastes may have been handled, spilled, or buried.
The individual sites are currently referred to as potential sources of contamination (PSCs). The term "site"
is applied to PSCs that are currently under investigation at NAS Cecil Field as part of the IR program. At
i
the time of the facility's listing on the NPL, 18 sites had been identified. The RFI (Harding Lawson
Associates, 1988) identified another site (Site 19). Remedial response activities are currently underway at
Sites 1, 2, 3, 5, 7. 8, 10, 11, 14, 15/16, and 17. Field investigation plans were prepared for the
investigation of PSCs 4, 6, 9, 12, 18, and 19 (ABB-ES, 1995). Site 13 was transferred to the underground
storage tank (UST) program.
In 1993, NAS Cecil Field was selected for closure by the Base Realignment and Closure (BRAC)
Commission. An environmental baseline survey (EBS) was completed as the first step in the closure
process. The EBS identified parcels of land for sale, lease, or investigation, depending on the condition of
the parcel. OU8 was designated in the November 1994 EBS as "BRAC Category 6" (release of
hazardous substances has occurred, but required remedial actions have not yet been taken) (ABB-ES,
049811/P 2-4 CTO0039
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1994). This classification was based on the seven categories defined in the BRAC Cleanup Guidance
Manual (Department of Defense. 1993).
In October 1993. at the 1994 Fiscal Year Site Management Plan meeting, the U.S. EPA, FDEP, and the
Navy decided to identify Site 3 as a separate OU. In previous investigations, Site 3 was part of OU2
(originally composed of Sites 3, 5, and 17). The investigations for Sites 5 and 17 of OU2 were completed
at a time when Site 3 still required further investigation. To avoid delay and to facilitate investigation
progress on all three sites of OU2, Site 3 was designated as OU8 and the Remedial
Investigation/Feasibility Study (RI/FS) for Sites 5 and 17 under OU2 proceeded. The site-specific history
is presented below.
A pit, designated as the Oil and Sludge Disposal Pit, was used at Site 3 to dispose of liquid wastes and
sludge generated by the facility. The IAS (Envirodyne Engineers, 1985) estimated that disposal
operations at Site 3 occurred from as early as the mid-1950s until 1975. However, based on a review of
aerial photographs of the area, no disturbance was observed in the pit area on a 1960 photograph; it
appears that OU8 disposal operations began between 1960 and 1969. An aerial photograph taken in
1969 shows the basic outline of the pit to be circular and about 100 feet in diameter (8,000 ft2). It is
estimated that the pit was 3 to 5 feet deep. The photograph also shows a linear feature, approximately 10
feet wide and 50 feet long, south of the disturbed area that appears to be a trench filled with liquid. Aerial
photographs from 1972,1973,1975, and 1984 show that OU8 became progressively more vegetated over
this time, indicating that disposal activities were discontinued some time in the early 1970s.
Liquid wastes were typically taken to the site from the individual shops (i.e., the fuel farm, Public Works,
Aircraft Intermediate Maintenance Department [AIMD], and the squadrons) in bowsers (trailer-mounted
tanks) or 55-gallon drums, drained intp the pit, and allowed to seep into the soil or evaporate. The pit
wastes were burned when the liquid level approached the top. This procedure was repeated
approximately once every 3 months by the fire department (Envirodyne Engineers, 1985).
An estimated 200 to 300 gallons of waste oil, fuel, and tank sludge from the fuel farm were disposed
weekly at the site. Although much of this volume consisted of water, it is estimated that between 210,000
and 310,000 gallons of fuel farm wastes were disposed throughout the operation (20 years) of the site.
Other liquid wastes generated by the squadrons, AIMD, and Public Works also were disposed of at Site 3.
These wastes included fuel, oil, solvent, paint, and paint stripper. No records were kept on disposal
practices, and access to the site was uncontrolled; therefore, the amount of the liquid wastes disposed of
at Site 3 from these sources is unknown.
049811/P 2-5 CT00039
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Estimates developed during the I AS (Envirodyne Engineers, 1985) indicate that the total quantity of
wastes from all sources disposed during the site operation are: waste paint - 4.200 gallons; spent
solvent -110,000 gallons; paint thinner - 20,000 gallons; petroleum-oil-lubricant wastes - 440,000 gallons;
and waste fuel-, oil-, and sludge-contaminated water - 210,000 to 310,000 gallons. Following closure of
the site in 1975, the pit was filled soil (Envirodyne Engineers, 1985).
On February 8, 1992, a Navy helicopter crashed into a wooded area approximately 800 feet east of the
OU8 disposal pit (see Figure 2-2). The helicopter had a fuel capacity of between 1,800 and 2,000 gallons
and ignited on impact. Soil and groundwater contamination as a result of the crash were initially assessed
by Environmental Science and Engineering, Inc., in August and September 1993 during a contamination
assessment (CA). The results of the CA were presented in a Preliminary Contamination Assessment
Report.
2.3 HIGHLIGHTS OF COMMUNITY PARTICIPATION
The results of the Rl and BRA, the remedial alternatives identified in the FS, and the preferred alternative
described in the Proposed Plan were presented to the NAS Cecil Field Restoration Advisory Board (RAB)
on January 13,1998. The RAB is comprised of community members as wells as representatives from the
Navy and State and Federal regulatory agencies.
Public notice of the availability of the Proposed Plan was placed in the Metro section of the Florida Times
Union on January 25, 1998. This local edition targets the communities closest to NAS Cecil Field.
Documents pertaining to Site 3 are available to the public at the Information Repository, located at the
Charles D. Webb Wesonnett Branch of the Jacksonville Library, 6887 103rd Street, Jacksonville, Florida.
i
A 30-day public comment period was held from January 26 through February 25, 1998. No comments
were received during the comment period.
2.4 SCOPE AND ROLE OF OPERABLE UNIT
The environmental concerns at NAS Cecil Field are complex. As a result, work at the 18 sites has been
organized into eight installation restoration OUs. More than 100 other areas are undergoing evaluation in
the BRAC and UST petroleum programs.
Final RODs have been approved for OUs 1, 2, 4, and 7. RIs, BRAs, and FSs have been completed for
OUs 3. 5, 6, and 8.
049811/P 2-6 CTO0039
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Assessment of environmental data collected from OU 8, Site 3, the subject of this ROD, indicates
groundwater contamination could pose an unacceptable human health risk if the groundwater was used
as a potable water source. Future discharge of groundwater to Rowell Creek could potentially cause
adverse effects on aquatic organisms. The purpose of this remedial action (RA) is to monitor and
remediate the groundwater contamination that pose human health and ecological risks. Ingestion of
groundwater from the surficial aquifer poses an excess lifetime cancer risk (ELCR) that exceeds the State
of Florida threshold of 1 in 1,000,000 or 1E-06.
The following remedial action objective (RAO) was established for Site 3:
• Prevent exposure to groundwater that contains VOCs at concentrations that are greater than the State
of Florida guidance criteria and that cause unacceptable risk to human health.
The RA documented in this ROD will achieve this RAO.
2.5 SUMMARY OF SITE CHARACTERISTICS
2.5.1 Hvdroqeoloav
At MAS Cecil Field, there are three water-bearing systems: the surficial aquifer, the intermediate aquifer,
and the Floridan aquifer systems. Each system is separate from the next by an aquitard or less
permeable unit. The Floridan aquifer system was not encountered during the investigation at OU8.
2.5.1.1 Surficial Aquifer System
I
The undifferentiated sediments in the surficial aquifer system in the area of OU8 consist of mostly quartz
sand with some clayey sand and up to 10 percent silt and clay. Well screens were placed to investigate
conditions in the upper (UZS), intermediate (IZS), and lower (LZS) zones of the surficial aquifer system.
The surficial aquifer system is under water table conditions (unconfined).
The general groundwater flow direction in the surficial aquifer is to the east-southeast toward Rowell
Creek. There is also a downward flow gradient that is evident at the waste disposal pit area and continues
for approximately 900 to 1,000 feet downgradient of the pit. At this point, the vertical flow potential
becomes upward. Both the upward and horizontal gradients become increasingly steep over the
remaining 300 to 400 feet eastward to Rowell Creek. The pronounced upward gradients indicate that the
049811/P 2-7 CTO0039
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surficial aquifer discharges to Rowell Creek. In the wetlands west of Rowell Creek, the water table is near
the land surface, but groundwater has not been observed discharging to the land surface.
The seepage velocity, or the rate at which groundwater moves through the aquifer, was calculated for
each gradient area of the surficial aquifer. For the entire distance from the waste disposal pit area to
Rowell Creek, the seepage velocity is estimated at 88 feet per year (ft/yr). At the waste disposal pit area,
the seepage velocity is estimated at 27 ft/yr. In the last 300 feet before Rowell Creek, a seepage velocity
of 190 ft/yr is estimated.
2.5.1.2 Intermediate Aquifer System
In the MAS Cecil Field area, the intermediate aquifer system or confining unit consists of sediments
assigned to the Miocene Hawthorn Group. In addition to its clay-rich sediments, the Hawthorn includes
near its top, a locally continuous carbonate-rich unit of dolomite with significant secondary (e.g., fractures)
porosity, possibly including shell hash or sand bodies. This carbonate-rich unit forms the historic "rock
aquifer" or "secondary artesian aquifer,* a water-bearing unit widely used in this region as a private
drinking water source. For this ROD, this unit will be referred to as the upper zone of the Hawthorn (UZH).
The unit is approximately 20 to 25 feet thick and occurs at a depth of 100 to 125 feet below land surface
(bis). The top of this unit is irregular and may represent an erosional unconformity. The total thickness of
the entire Hawthorn Group (including the underlying clayey confining beds) exceeds 300 feet in this area
(Scott etal., 1991)
At OU8, the groundwater flow direction in the intermediate aquifer is to the east-southeast, toward Rowell
Creek. A vertical upward gradient from the intermediate aquifer to the surficial aquifer is present. For the
intermediate aquifer, a seepage velocity of 0.20 ft/day or 73 ft/yr was calculated.
2.5.2 Contaminant Sources
At OU8, the primary source of contamination is considered to be the liquid wastes (described earlier) that
were deposited in the disposal pit. Another possible source area of contamination, unrelated to the waste
disposal pits, is the helicopter crash site.
The OU8 Rl. completed in 1994, investigated surface soil, subsurface soil, groundwater, sediment, and
surface water. Field screening and confirmatory sampling programs were conducted for soil and
groundwater at OU8. The evaluation of investigative results indicates that contaminants were found in
samples from all media sampled, though not all detected constituents were attributable to waste disposal
activities at Site 3.
049811/P 2-8 CTO0039
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The results of the Rl are summarized, by medium, in the following paragraphs.
2.5.2.1 Soil
The results of the confirmatory soil sampling and analytical program indicate the presence of VOCs,
semivolatile organic compounds (SVOCs), total recoverable petroleum hydrocarbons (TRPH), pesticides,
poly chlorinated biphenyls (PCBs), and inorganics in both surface and subsurface soil.
In the 1994 investigation, an extensive surface and subsurface soil sample screening program was
undertaken (Figures 2-3 and 2-4); confirmatory soil sampling and chemical analysis followed the
screening program (Figure 2-5). Between the 1991 and 1994 investigations, 37 subsurface soil samples
were used to evaluate the nature and extent of contamination at OU8.
Surface Soil
The most frequent VOC detected in the 24 surface soil samples (0 to 1 foot bis) was xylene (12 of 24
samples), a common component of fuel, at concentrations ranging from 3 to 8 micrograms per kilogram
(ug/kg). All other VOCs had a frequency of detection of 2 out of 24 samples or less and were detected at
concentrations below 5 ug/kg. None of these detections exceeded the FDEP residential Soil Cleanup
Goals (SCGs). VOC detected in both surface and subsurface soil is depicted on Figure 2-6.
Several SVOCs were detected in surface soil, although no single SVOC was detected in more than four of
the 24 samples collected. Many of the detected SVOCs are commonly found in fuel and waste oil, both of
which were reportedly disposed at OU8.' The maximum concentration of benzo(a)pyrene (440 M9/kg)
exceeded the FDEP residential SCG (100 ug/kg).
i
TRPH was detected in 6 of the 24 surface soil samples; detections were in both the disposal pit area and
the helicopter crash area. The presence of TRPH at OU8 is likely attributable to historic activities at these
areas.
A few pesticides and one PCB isomer (Aroclor-1254) were detected in surface soil. None of these
detections exceed the FDEP residential SCGs. Because of wide distribution and low concentrations of the
pesticides and PCB, the detections are interpreted to be the result of former basewide pesticide
049811/P 2-9 CTO0039
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049811/P 2-10 CTO0039
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r!993 Helicopter
\ crash site area
of invesligolion
• >•'• »l-l 1
"* • l-l 1" 'i» '•"*
^ • »l'tl MJt
,. , , ».-.» «.|
r L* t iti i.ii'U'*^**1* 1"1""' • i-«
FIGURE 2-3
SURFACE SOIL SCREENING LOCATIONS
RECORD OF DECISION
OPERABLE UNIT 8
Suftoc* toil Udcnin) locotion
lrt< Um
NAVAL A« STATION CEC1 FIELD
JACKSONVUE. aORDA
04MII/P
2-11
CTO0039
-------
Htlicopltr crash
til* OCCMI rood
f~ Appro«imott «tiq« ol
1993 Htlicopttr
crash lit* ar«o
of investigation
Wolt«»oter tr«a(men
1.7*. plant outfoll
FIGURE 2^
SUBSURFACE SOIL AND GROUNDWATER
SCREENING LOCATIONS
LEGEND
• SukwlKi Mil »>d (roiiMeotff uiltnuif
Int
RECORD OF DECISION
OPERABLE UNIT I
HAYU Wl STATION CEC1 FZLD
J1W50NVUL aORDt
CToom*
-------
Htficopttr croih
lit* occtn rood
Htlicopt
crash sit* on
Invtsligotion
Woittwottr trtatmcn
plant outfall
,—Citent ol greundwatf
/ contamination
i ICHJSJS v
CfJSJN
UCENO
tatmntdiolf monito'inj ««d locglion
nwnitonng ••• lacalmn
Slalt* monilwing »tH lotolioo
Surfwi loH 9amplii<9 IOCOIHW (0 to 1 tool bdw und lurtoc«)
Mil tomplinf IxoKon
Mi »utmjfloc« and turfoei nil umpbtg kKafion
J«4o» •alir/Hdimtnl tampliiia
FKJURtM
coNnMUTOirr suvAct ANO SUBSUMTACC so*.
SeOOIENT. SUVACC MATE* ANO
MOWTOIONO WCLL SAWUNO LOCATION*
RECORD OF DECISION
OPERABLE UNIT 8
MVU in STATION C£C1 FIQjO
2-15
CTO003*
-------
fP.lTWEU
=====
" lck«fr«Wl Oom
Hvlieepltr crash
sit* occiss road
H«licopl«r
crash sit* or«o
el Invtstigation
Waslfwatir trtotmtn
plant outfall
Huloncal,
pit ar«a-l '««•''-
LECENO
Surfoti
Suttwriou ioS
FIGURE 2-4
TCE. TRPH. AND TOTAL VOC* IN
SURFACE AND SUBSURFACE SOIL
lecaKan (0 to I tol Into, tend
TricMWMllMM
JO mWoromj p« t9«gram TM eoMtntralion contour
•»trag« al umplt and dupficali
Cilimolo4 nlwi
Tret
foiict
RECORD OF DECISION
OPERABLE UNIT 8
IUVAI AW STATION CEC& FEU)
JACXSONVUL nORBA
lC«l.t: I MCM • -M fCtl
04U11IP
2-17
CTOOQOS
-------
applications and the suspected past practice of using oil that contained PCBs for dust control along
unpaved roads, and are not attributed to disposal operations at OU8. Sampling of road dust has been
conducted, and no PCBs were identified. Contaminants present along roadways at NAS Cecil Field are
being investigated under the BRAC program.
Five inorganics in OU8 surface soil exceeded background screening concentrations specific to NAS Cecil
Field and referred to as Hi-Cut values. These inorganics include cadmium, copper, mercury, silver, and
zinc. The inorganics most frequently detected and with the highest concentrations were located within or
near the former disposal pit. The helicopter crash area typically had inorganic concentrations near or
below the background screening concentrations and also had fewer total inorganic contaminants detected
than the disposal pit area. None of the metals detected exceeded the FDEP residential SCGs.
Subsurface Soil
Evaluation of results for the subsurface soil samples indicates that VOCs, SVOCs, and inorganics appear
to be related to past disposal practices and the helicopter crash because the highest concentrations were
detected near the disposal pit area and the helicopter crash site. Pesticides and PCBs were not detected
frequently and have a sporadic distribution, indicating that they are probably not related to historic disposal
activities at the disposal pit area.
The VOC detections were primarily chlorinated solvents and fuel-related VOCs and appear to be related
to the previous waste disposal operations at OU8. Detections of these compounds in subsurface soil near
the helicopter crash site are believed to be the result of volatilization of VOCs in groundwater, which is
within two feet of the land surface in this area.
I
Trichloroethlene (TCE) was detected in 5 out of 37 subsurface soil samples. There were two TCE
detections in subsurface samples located in the vadose zone in the disposal pit area, with the highest
detection of 270 M9/kg occurring in the'sample from soil boring CEF-3-BOR-6. The maximum
concentration of TCE (270 ug/kg) exceeded the FDEP SCG based on teachability from soil to groundwater
(1.46 ug/kg). These two TCE detections were the only subsurface soil detections that were in the vadose
zone. The other detections were in the saturated zone. The Summers model and the U.S. EPA Batch
model (U.S. EPA, 1989) were used to assess whether vadose zone soil contaminated with TCE (i.e.,
vadose zone soil in the disposal pit area) would continue to act as a source of groundwater contamination
(i.e., would produce leachate containing TCE above the State of Florida groundwater guidance
concentration of 3 micrograms per liter [ug/l]) and, if so, to determine how long it would take for vadose
zone soil in the disposal pit area to be flushed so that TCE in subsurface soil would no longer act as a
049811/P 2-19 CTO0039
-------
source. The Summers and Batch model results indicated that it would take 23 years to flush the vadose
zone soil in the disposal pit area so that the TCE in the upper 10 feet of the surficial aquifer would be less
than 3 ug/l.
Several SVOCs were detected in subsurface soil at OU8. The most commonly detected SVOCs included
1,4-dichlorobenzene (OCB) and bis(2-ethylhexyl)phthalate. None of these detections exceeded the FDEP
SCG based on teachability from soil to groundwater. Of these two compounds, bis(2-ethylhexyl)phthalate
had the most detections (15) and was detected at the highest concentrations (6.800 ug/kg). As with
VOCs, SVOCs appear to have the highest concentrations at locations within the disposal pit boundary and
are most likely attributable to past disposal activities.
TRPH was detected in 20 of 37 subsurface soil samples from both the disposal pit area and the helicopter
crash site, with a maximum detection of 1,600 milligrams per kilogram (mg/kg). The presence of TRPH is
believed to be linked to historic activities in these areas.
The most frequently detected inorganics exceeding Hi-Cut values were barium, calcium, chromium,
copper, magnesium, and nickel. In addition, cadmium, cyanide, and zinc were detected in at least one
subsurface soil sample at the site above Hi-Cut values.
Based on the results of the confirmatory soil sampling and analysis, it is estimated that an average TCE
concentration of 146 ug/kg remains in the vadose zone soil near the disposal pit at OU8 over an area of
approximately 8,000 ft2 and that this contaminated soil will continue to act as a source of groundwater
contamination for 23 years. This is a conservative assumption based on two detections of TCE in vadose
zone soil in the disposal pit area.
>
2.5.2.2 Groundwater
A total of 37 monitoring wells were installed at OU8 during field investigations. One well, CEF-3-2, was
abandoned because of an inappropriate screen length (30 feet). Of the 36 remaining wells, 33 are
screened in the surficial aquifer and 3 are screened in the intermediate aquifer (UZH). Of the 33 wells
installed in the surficial aquifer, 16 are screened in the shallow zone (UZS water table to approximately 30
feet bis), 6 are screened in the intermediate zone (IZS: 30 to 77 feet bis), and 11 are screened in the
deep or lower zone (LZS: 60 to 100 feet bis). Evaluation of the analytical results indicates that
groundwater in the surficial aquifer at OU8 contains VOCs, SVOCs, pesticides, PCBs, and inorganics.
Not all constituents detected in groundwater appear to be related to past disposal activities at OU8.
Discussion of groundwater results is limited to unfiltered samples.
049811/P 2-20 CTO0039
-------
Ten VOCs were detected in groundwater samples collected from the surficial aquifer. Five of these 10
compounds exceeded human health risk criteria: 1,1-dichloroethane, 1,1-dichloroethene (DCE), 1,2-DCE,
TCE, and benzene. The maximum detected concentrations of 1,1,1-trichloroethane, 1.1-DCE, 1,2-DCE
(total), benzene, and TCE exceeded the FDEP groundwater guidance concentrations. No VOCs were
detected in the intermediate aquifer at OU8.
VOCs in the surficial aquifer appear to have migrated with the natural flow of groundwater approximately
1,400 feet, from the former waste disposal pit area to Rowell Creek. The assumption that the surficial
aquifer discharges to Rowell Creek is supported by the fact that no VOCs were detected in monitoring
wells located east of Rowell Creek.
The migration pattern of VOCs from the disposal pit area at OU8 is confirmed by the vertical distribution of
TCE and 1,1-DCE, two constituents detected in both screening and confirmatory groundwater samples.
Representative Aquaprobe™ screening samples were used to help delineate the vertical extent of VOC
contamination at the center of the OU8 plume where no groundwater monitoring wells exist.
Contaminants are understood to have migrated downward and eastward through the aquifer from the
disposal pit, to a maximum depth of approximately 70 feet bis (in the approximate center of the plume 500
to 800 feet downgradient of the pit), and to have continued to move eastward and upward with the natural
groundwater flow until discharged to Rowell Creek. Solvent contamination detected in surface soil and
groundwater at the helicopter crash site is understood to be attributable to contaminant migration rather
than to the crash.
It is estimated that all groundwater presently containing more than 3 ug/l of TCE would flush to Rowell
Creek in approximately 39 years. TCE concentrations were modeled because this chemical is widely
»
distributed at OU8. The estimate assumes that it would take approximately 17 years to flush one plume
volume of groundwater from OU8 to Rowell Creek,' using an effective porosity of 0.20 and a TCE
retardation factor of 2.3. This time estimate'does not take into account any leaching of TCE from soil into
groundwater. As discussed previously, soil in the disposal area containing an average TCE concentration
of 146 ng/kg will continue to leach to groundwater over a 23-year period. Therefore, it is estimated that
the total amount of time that TCE would leach into groundwater (at concentrations higher than 3 ng/l) and
flush into Rowell Creek ranges from 39 to 62 years.
A total of 14 SVOCs were detected in groundwater samples collected from the surficial aquifer. A limited
number of SVOCs were detected in the intermediate aquifer but not in shallow UZS wells nearby (Figure
2-7). Of the 14 compounds detected in the surficial aquifer, 6 were identified as characteristic of disposal
049811/P 2-21 CTO0039
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This page is intentionally left blank.
049811/P 2-22 CT00039
-------
•«. 14
. .J-OCC I4CO
! ttt 'JOG
j I.J-OCI trtj
I M-OCI tUl
, 1.2-OCI SUOJ j
H»heopl«r crash
jilt occtsi road
Approvirrotr tact of roa
I.J-OCI
J-«"
i.i-oci
I.I-OCI
— Extent of groundwolcr
Wastewatir Ircatmtn
plant outfall
i-j-oa
I i.t-oci
jl.l-DU
CCF-J-91
ccr-3-ioo
OMP monitoring *tl location
SnollO' ironiloring >t>l locglion
Cr-S>/S8-l£ SurlKt .ct.r/irtimt-.l igmpling
FIGURE 2-7
ORGANICS IN THE SURFICUL AQUIFER
1.1-OicMoratliMfii
1.2-OicMerMlhm
rricMo/Mttitnt
1,1-OiCNVMUMin
tmm
tltimoltd >«JM
RECORD OF DECISION
OPERABLE UNIT «
Dirt ntM4 human htollli ria
rU wmwwnl vt slum.
mknyemt O4r n*r.
turn An tTATmi ecu FOD
CT0003*
-------
practices at OU8: 1,2-DCB, 1,4-DCB, ben2o(b)flouranthene, naphthalene, 4-methylphenol, and
bis(2'ethylhexyl)phthalate. The maximum concentration of 1,2-DCB. 1,4-DCB and 4-methylphend
exceeded FDEP ground water guidance concentrations.
The only pesticides and PCBs detected in the groundwater at OU8 were the pesticides endosulfan II and
beta-benzene hexachloride and the PCB Arcolor-1248. Aroclor-1248 was detected in samples from two
monitoring wells, both of which are located in the disposal pit area, at concentrations of 0.6 ug/l
(CEF-3-4S) and 0.79 ug/l (CEF-3-6S). These concentrations exceed FDEP groundwater guidance
concentrations. PCB detections may be related to the disposal of waste oil.
Eighteen inorganics were detected in unfiltered groundwater samples collected from the surficial aquifer.
Of these 18 inorganics, arsenic, chromium, manganese, and vanadium exceeded human health risk
criteria and appeared to have elevated concentrations in the vicinity of the disposal pit. The maximum
concentrations of aluminum, iron, and manganese exceed FDEP groundwater guidance concentrations.
Arsenic concentrations are higher in the LZS as opposed to the UZS, where most site-related
contaminants were detected. Therefore, arsenic is believed to be indigenous to the aquifer in this area
and unrelated to disposal practices at OU8. Manganese was widely distributed throughout the surficial
aquifer and was present in an upgradient well; its presence is also interpreted as not attributable to
disposal practices at OU8. Chromium may be related to disposal practices because it was detected in
UZS wells in the disposal pit area.
Arsenic and manganese also were detected in the intermediate aquifer; however, they were below
surficial aquifer Hi-Cut values and are not believed to be related to disposal practices at OU8. The
maximum concentration of aluminum exceeded the FDEP groundwater concentration, which is well below
the surficial aquifer Hi-Cut value.
»
Based on the vertical and lateral distribution of organic contaminants, and a porosity of 0.20, the volume of
contaminated groundwater in the surficial aquifer is estimated at 50 million gallons.
2.5.2.3 Surface Water and Sediment
Three surface water and sediment samples were collected from three locations in Rowell Creek. Four
organic compounds were detected in the surface water samples collected for OU8:
bromodichloromethane, dibromochloromethane, methylene chloride, and chloroform. With the exception
of methylene chloride (a common laboratory contaminant that was not detected in groundwater at OU8),
these VOCs are most likely attributable to the wastewater treatment plant effluent, which enters Rowell
049811/P 2-25 CTO0039
-------
Creek near the base of the Lake Fretwell dam upstream of these sampling locations. These VOCs are
common by-products of the chlorination process used during the treatment of wastewater. All
concentrations were below FDEP water quality standards.
Organics detected in groundwater at OU8 (TCE in particular) were most likely not detected in surface
water because of biodegradation as the groundwater migrates through streambed sediment or dilution of
the groundwater as it discharges to Rowell Creek. It is estimated that groundwater discharging to surface
water is diluted 99.2 percent, or 133 times. Appendix K of the Rl report (ABB-ES, 1997c) contains
calculations for estimating this dilution.
Three organic compounds were detected in the sediment samples collected at OU8: one VOC,
2-butanone, and two SVOCs, di-n-butylphthalate and bis(2-ethylhexyl)phthalate. Due to their absence in
nearby surface soil samples and groundwater samples from the UZS west of Rowell Creek, the presence
of these compounds in sediment is not believed to be linked to the disposal pit area.
One pesticide was detected in the background surface water sample CEF-SW/SD-2. Four pesticides and
one PCS isomer were detected in sediment samples. The presence of these compounds is believed to be
attributable to basewide pesticide use and the past practice of using oil containing PCBs as a road dust
suppressant.
Five inorganic contaminants detected in surface water samples were identified as chemicals of potential
concern (COPCs) in the Rl: aluminum, antimony, iron, lead, and silver. Of these five inorganics, only iron
was detected in the upstream background sample CF-SD-2. Antimony, lead, and silver were not
detected in samples from nearby monitoring well CEF-3-31S. The concentrations of all these inorganics
were less than Hi-Cut values. The single detection of silver exceeded the FDEP water quality standard.
1
Four inorganic contaminants detected in sediment samples were identified as COPCs in the Rl: barium,
copper, lead, and zinc. Barium, copper,* and zinc were not detected in the upstream background sample
CF-SD-2. Lead was detected in both sediment sample locations and the upstream background sample.
The upstream background screening lead concentration of 5.8 mg/kg is nearly the same as that at
RC-SD-3 (6.2 mg/kg). The concentrations of all these inorganics were less than the Hi-Cut values.
i*
Although barium and lead were detected in surface soil samples collected from the helicopter crash site
area, the concentrations did not exceed the Hi-Cut values. Therefore, surfaces soil does not appear to be
the source of the analytes detected in the sediment samples. Copper also was detected in surface soil
samples at the helicopter crash site but at concentrations lower than those detected in sediment.
049811/P 2-26 CTO0039
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2.6 SUMMARY OF SITE RISKS
The BRA (ABB-ES, 1997b) provides the basis for taking action and indicates the exposure pathways to be
addressed by the remedial action. This section of the ROD reports the result of the BRA conducted for
this site. Information on identification of chemicals of concern, exposure assessment, toxicity
assessment, and risk characterization are provided in detail in the Rl (ABB-ES, 1997c). The BRA results,
indicate that unacceptable risks could exist if no action were taken at the site. Human health risks and
potential ecological risks were identified at Site 3. Actual or threatened releases of hazardous substances
from this site, if not addressed by implementing the RA selected in this ROD, may present an imminent
and substantial endangerment to public health, welfare, and the environment.
Human health threats include both a cancer risk and a noncancer hazard index (HI) in accordance with
the NCR. The NCP establishes 1 in 1,000.000 (1E-06) to 1 in 10,000 (1E-04) as an "acceptable" excess
lifetime cancer risk (ELCR) from chemicals of potential concern (COPCs) (U.S. EPA, 1990). For
noncarcinogenic chemicals, an HI of equal to or less than one is acceptable. The State of Florida
established an acceptable ELCR as equal to or less than 1E-06 and an HI equal to or less than one.
2.6.1 Human Health Risk Assessment
Adverse health effects from carcinogens and noncarcinogens associated with current land use at OU8 are
not of concern. Cancer risk estimates associated with future use of OUS surface soil, subsurface soil,
surface water, sediment, and intermediate aquifer groundwater are all below or within the acceptable risk
range defined by U.S. EPA. However, risks to a future resident exposed to surface soil, intermediate
aquifer groundwater, and sediment exceeded the State of Florida acceptable ELCR. In addition, the
ELCR associated with ingestion of groundwater from the surficial aquifer under a potential future land-use
scenario (adult resident) is 3E-03, which exceeds U.S. EPA and the State of Florida acceptable cancer
risk ranges. The major contaminants contributing to the ELCR for the future adult resident are 1,1 -DCE
(ELCR = 3E-03), TCE (ELCR = 2E-04). 1.4-DCB (ELCR = 2E-04). and arsenic (ELCR = 2E-04). A
summary of the human heath risks is provided in Table 2-1.
Noncancer HI estimates associated with future use of OUS surface soil, subsurface soil, surface water,
sediment, and intermediate aquifer groundwater are all equal to or less than one. The noncancer HI
associated with ingestion of groundwater from the surficial aquifer under the potential future land-use
scenario (adult resident) is 20. Major contributors to this HI are TCE (hazard quotient [HQ] = 7.8),
1,2-DCE (total) (HQ = 5.8), 1,2-DCB (HQ = 3.0), and 1,1-DCE (HQ = 1.1).
049811/P 2-27 CT00039
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S
to
oo
TABLE 2-1
HUMAN HEALTH RISK SUMMARY
OPERABLE UNIT 8, SITE 3
NAVAL AIR STATION CECIL FIELD
JACKSONVILLE, FLORIDA
Medium
Surface Soil
Subsurface Soil
Surface Water
Sediment
Surficial Aquifer Groundwater
Intermediate Aquifer Groundwater
Risks Above
U.S. EPA Risk Range?'1'
Current Land
Use(2)
No
NA
No
No
NA
NA
Future Land
Use'3'
No
No
No
No
L Yes
No
Risks Above
FDEP Risk Range?'*'
Current Land
Use'2'
No
NA
No
No
NA
NA
Future Land
Use'3'
Yes
No
No
Yes
Yes
No
Concentrations Above
Florida Soil Cleanup Goals on
Groundwater Guidance Criteria?'5'
Yes'6'
Yes'7'
NA
NA
Yes'8'
Yes'9'
ro
b
oo
1 U.S. EPA has established an acceptable ELCR range of 1E-06 to 1E-04 (U.S.EPA, 1990) and a maximum non-carcinogen HI of
1.0.
2 Current land uses evaluated in this report include nonresidential exposures with no current use of groundwater.
3 Potential future land uses evaluated in this report include residential exposures with the use of groundwater as drinking water.
4 FDEP has established an acceptable ELCR threshold of 1E-06 and a maximum non-carcinogen HI of 1.0.
5 Florida Soil cleanup goals are identified in the Florida Department of Environmental Protection (FEDP) memorandum dated
September 29,1995 (FDEP, 1995). Florida guidance concentrations are taken from Chapter 6 (Guidance Concentrations Index) of
the FDEP groundwater concentrations issued in June 1994 (FDEP, 1994).
6 In surface soil, the maximum concentration of benzo(a)pyrene exceeded the Florida soil cleanup goal.
7 In subsurface soil, the maximum concentration of trichloroethene exceeded the Florida guidance concentration for leaching to
groundwater.
8 In the surficial aquifer, the maximum detected concentrations of 1,1,1 -trichloroethane, 1,1-dichloroethene, 1,2-dichloroethene
(total), benzene, trichloroethene, 1,2-dichlorobenzene, 1,4-dichlorobenzene, 4-methylphenol, Aroclor-1248, aluminum, antimony,
iron, manganese exceeded their respective Florida guidance concentrations.
9 In the intermediate aquifer, the maximum concentration of aluminum exceeded the Florida guidance concentration.
Note: U.S. EPA = U.S. Environmental Protection Agency
NA = not applicable
o
cl
-------
Concern over the contamination in the surficial aquifer may be warranted because of the possibility of
adverse health effects (cancer and noncancer) associated with assumed future use of the groundwater as
a potable water supply. However, use of the surficial aquifer as a potable water supply at OU8 may never
occur because NAS Cecil Field is served by a community water supply system.
An analysis was conducted to determine if there would be any human health risk associated with
discharge of surficial aquifer groundwater to Rowell Creek. The maximum detected concentration of
chemicals in surficial aquifer groundwater were divided by a dilution factor of 133 to obtain an estimated
surface water concentration. These surface water concentrations were then compared to the U.S. EPA
Region III risk-based concentrations (RBCs) for tap (potable) water (U.S. EPA, 1994) and background
screening concentrations. Any analyte that exceeded either of these screening criteria was retained as an
human health COPC. Exposure to surface water by an adult and child resident was evaluated because
these are the most conservative scenarios for surface water exposure. The ELCR for a future resident
(child and adult) was 2E-06, which is within the U.S. EPA acceptable risk range. The His associated with
the child (HI = 0.5) and adult (HI = 0.3) were both below the threshold level of one. In summary, discharge
of the surficial aquifer groundwater into Rowell Creek is not associated with any unacceptable human
health effects.
Based on the results of the human health BRA, the development of remedial action strategies are
necessary for the surficial aquifer groundwater at OU8.
2.6.2 Ecological Risk Assessment
Potential risks to ecological receptors were evaluated for chemicals in surface soil, surface water,
sediment, and groundwater at OU8. Results indicate that ecological receptors are not likely to be at risk
from exposure to OU8 surface soil, surface water, or sediment. Adverse effects to aquatic organisms
were observed in laboratory toxicity studies from exposure to undiluted OU8 groundwater. A summary of
potential risks to ecologic receptors is provided in Table 2-2.
049811/P 2-29 CT00039
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I
$
TABLE 2-2
SUMMARY OF RISK CHARACTERIZATION FOR WILDLIFE, PLANT, AND INVERTEBRATE RECEPTORS
SITE 3 OPERABLE UNIT 8
NAVAL AIR STATION CECIL FIELD
JACKSONVILLE, FLORIDA
Receptor
Terrestrial and wetland
wildlife
Terrestrial and wetland
plants
Soil invertebrates
Aquatic organisms
Aquatic organisms
Aquatic organisms
Biological Parameters
Food web modeling
Toxicity tests with
lettuce seeds
Toxicity tests with
earthworms
Benchmark comparison
Macroinvertebrate
community structure
analysis
Laboratory toxicity tests
with water fleas and
fathead minnows
Risk Estimated (per Medium)
Surface Soil
None
None'"
None
NA
NA
NA
Surface Water
None
NA
NA
Minimal to none
Poor habitat quality
NA
Sediment
None
NA
NA
Minimal to none
Poor habitat quality
NA
Future Groundwater Discharge
NA
NA
NA
Adverse effects possible"
NA
Reduced reproduction, growth,
and survival observed13'
1 Slight reduction of lettuce seed germination believed to be associated with a noncontaminant stressor.
2 Adverse effects from dichlorobenzene, bis(2-ethylhexyl)phthalate, Aroclor-1248, aluminum, chromium (unfiltered only), copper, and iron were estimated
for current undiluted concentrations of groundwater. Adverse effects from only 1 ,2-dichlorobenzene and possibly aluminum were estimated for future
diluted concentrations of groundwater.
3 Concentrations of 1,1-dichloroethane, dichlorobenzene, aluminum, chromium, copper, iron, and lead detected in the groundwater used for the toxicity
tests exceed available benchmarks. It is believed that dichlorobenzene is the primary chemical causing adverse effects to the water flea and fathead
minnow.
to
w
o
o
o
o
8
to
Notes: None = no effect.
NA = not applicable.
-------
2.7 DESCRIPTION OF REMEDIAL ALTERNATIVES
2.7.1 Available Remedial Alternatives
Four types of general response actions were evaluated for groundwater during the RI/FS for Site 3:
1) Take limited or no action: Leave the site as it is, or restrict access and monitor it. While the no action
alternative would cost the least, it would not ensure the protection of human health and the
environment since it would leave a source of future contamination and would not monitor the
effectiveness of natural attenuation. Long-term natural attenuation monitoring and analysis of
groundwater and surface water would ensure that site remediation goals are being achieved and that
there are no adverse human health or environmental impacts from the potential spread of
contamination.
2) Contain contamination: Leave contamination where it is and cover or contain it in some way to
prevent exposure to, or spread of, contaminants. This method reduces risks from exposure to
contamination, but does not destroy or reduce the contamination.
3) Move contamination off site: Remove contaminated material (soil, groundwater, etc.) and dispose or
treat and then dispose in an offsite licensed disposal facility.
4) Treat contamination on site: Use chemical, physical, and/or natural processes to destroy, remove, or
reduce the contamination. Treated material can be left on site. If needed, contaminants captured by
the treatment process are disposed in an offsite licensed waste disposal facility.
Remedial alternatives for surface soil and sediments were not developed in the FS. Analytical results
indicate contamination exists above the FDEP Risk Range that could pose a risk under a future residential
scenario. These risks will be addressed through institutional controls. Types of land reuse will be limited
to industrial, commercial, and recreational uses. Residential (including housing, daycare and schools) and
agricultural uses are prohibited.
2.7.2 Groundwater Remedial Alternatives for Operable Unit 8. Site 3
The results of the BRA and the ecological risk assessment (ERA) indicate that adverse impacts to human
health and the environment are present only under the future use scenario for exposure to Site 3
groundwater. Therefore, only remedial action alternatives related to groundwater were evaluated.
049811/P 2-31 CTO0039
-------
2.7.2.1 No Action
Alternative MM-1: No Action
Evaluation of the no-action alternative is required by law to provide a baseline against which other
alternatives can be compared. Under this alternative, no remedial activities would occur to address
groundwater contamination and contaminant concentrations would be reduced only through natural
attenuation. No controls would be implemented to reduce exposure by human receptors. Contaminants
would attenuate naturally; however, periodic monitoring would not be performed to evaluate the
effectiveness of the no-action alternative in meeting clean-up goals and preventing the potential migration
of contaminants into Rowell Creek.
This alternative would not protect human health because risks from direct exposure to contaminated
groundwater would continue to exist. This alternative would not achieve the RAOs or comply with ARARs.
There would be no reduction of contaminant mobility and reduction in toxicity and volume would occur only
through long-term natural attenuation and would not be monitored. Because no remedial action would
take place, this alternative would not result in any short-term risks and would be very easy to implement.
There would be no cost associated with this alternative.
2.7.2.2 Natural Attenuation
Alternative MM-6: Natural Attenuation with Institutional Controls
This alternative would involve natural attenuation to reduce contaminant levels and the imposition of
deed/land use restrictions to reduce the potential for exposure to elevated levels of contaminants.
>
Under this alternative, limited action would be taken to reduce risks to human receptors. Groundwater
would be monitored to determine the degree of contaminant removal achieved through long-term natural
attenuation, administrative measures, such as deed restrictions, would be implemented to restrict land use
and prevent use of the surficial aquifer groundwater. Site reviews would be conducted every 5 years to
determine whether continued implementation of this alternative is appropriate.
This alternative would protect human health because it would reduce the risk from direct exposure to
contaminated groundwater. This alternative would achieve the RAOs and groundwater monitoring would
establish achievement of long-term compliance with ARARs through natural attenuation of residual
contaminants. There would be no reduction of contaminant mobility but long-term natural attenuation
would reduce the contaminant toxicity. There would be minimal short-term risk associated with the
049811/P 2-32 CTO0039
-------
performance of groundwater monitoring activities, which would be addressed through appropriate health
and safety procedures. It is estimated that the action levels would be met in 62 years. All of the activities
for this alternative would be easy to perform but their continued implementation, especially after the site is
no longer under military control, would require careful oversight. The present-worth cost would be
approximately $606,000.
2.7.2.3 In-situ Treatment
Alternative MM-2: Enhanced Biodegradation
This alternative relies on naturally-occurring microorganisms in the subsurface soil to breakdown the
organic contaminants. This alternative would enchance these naturally-occurring microorganisms by
ingestion of nutrients (nitrogen and phosphorus compounds) in the surficial aquifer, increasing their
abundance and thereby increasing the efficiency of their degradation of contaminants.
Bench-scale treatability studies would be performed to determine optimum nutrient composition. This
alternative also would include groundwater monitoring to evaluate the rate of biodegradation,
implementation of administrative measures to prevent groundwater use until compliance with action levels
had been achieved, and performance of 5-year reviews to determine whether continued implementation of
this alternative is appropriate.
Alternative MM-2 would protect human health because it would biodegrade the site contaminants and
prevent groundwater use until action levels were met. This alternative would achieve the RAOs and
comply with ARARs. Significant, permanent, and irreversible reduction of contaminant mobility, toxicity,
and volume would be achieved through biodegradation. Groundwater monitoring would determine the
rate and effectiveness of this reduction. Minimal short-term risk would be associated with the installation
and operation of the nutrient injection system and with the performance of groundwater monitoring
activities. These risks would be addressed through proper engineering controls and health and safety
procedures. This alternative would achieve compliance with action levels within approximately 12 years
and would be relatively easy to implement. The necessary equipment, materials, and construction
contractors are readily available. The present-worth cost would be approximately $3,652,000
Alternative MM-3: In-situ Air Stripping with Enhanced Biodegradation.
Alternative MM-3 is similar to Alternative MM-2, but would remove the high concentrations of VOCs from
the source area as an additional method of treatment. VOCs are removed from groundwater by forcing air
049811/P 2-33 CTO 0039
-------
under pressure into the aquifer and volatilizing them. The extracted vapors are treated above ground with
a regenerative thermal oxidation process that removes the VOCs. The enhanced biodegradation portion
of this alternative would occur in the downgradient part of the contaminant plume only, not the entire
plume as in Alternative MM-2. This alternative also would include groundwater monitoring to evaluate the
effectiveness of the remediation process, implementation of administrative measures to prevent
groundwater use until compliance with action levels has been achieved, and 5-year reviews to determine
whether continued implementation was appropriate.
Alternative MM-3 would protect human health because it would remove organic contaminants from the
groundwater and prevent groundwater use until action levels were met. It would achieve the RAOs and
comply with ARARs. Significant, permanent, and irreversible reductions in contaminant mobility, toxicity,
and volume would occur through volatilization and off-gas treatment. Groundwater monitoring would
determine the rate and effectiveness of this reduction. Some short-term risks would be associated with
the installation and operation of the air injection and vapor extraction and treatment system and with the
performance of groundwater monitoring activities. These risks would be addressed through proper
engineering controls and health and safety procedures. This alternative would achieve compliance with
action levels within approximately 12 years and would be relatively easy to implement. The necessary
equipment, materials, and construction contractors are readily available. The present-worth cost would be
approximately $3,322,000.
Alternative MM-7: In-situ Permeable Reactive Wall and Hydraulic Barriers
This alternative would use reactive materials installed as a permeable wall in the pathway of the
groundwater contaminant plume. Contaminants would be broken down into less harmful products through
chemical reactions with the zero-valent irpn material within the wall during the migration of groundwater
through the wall. Hydraulic barriers or impermeable walls would be installed parallel to the plume
movement to serve as a "funnel" to direct the groundwater plume through the reactive, permeable wall.
This alternative also would include groundwater monitoring to evaluate the effectiveness of the
remediation process, implementation of administrative measures, to prevent use of groundwater until
compliance with action levels had been achieved, and performance of 5-year reviews to determine
whether continued implementation of the alternative is appropriate.
Alternative MM-7 would protect human health because it would reduce the concentrations of the COPCs
within the groundwater and prevent its use until action levels were met. This alternative would achieve the
RAOs and would likely comply with ARARs. Significant, permanent, and irreversible reductions in
contaminant mobility, toxicity, and volume would be achieved. Groundwater monitoring would determine
049811/P . 2-34 CTO0039
-------
the rate and effectiveness of this reduction. Some short-term risks would be associated with the
construction and operation of the hydraulic barrier/treatment system and with the performance of
groundwater monitoring activities. These risks would be addressed through engineering controls and
health and safety procedures. Alternative MM-7 would achieve compliance with action levels within
approximately 62 years and would be relatively easy to implement. The necessary equipment, materials,
and construction contractors are readily available. The present-worth cost would be approximately
$2,170,000.
Alternative MM-8: In-situ Air Stripping with Phytoremediation Followed by Natural Attenuation
This alternative would use Alternative MM-3, described earlier, and phytoremediation. Phytoremediation
is the use of selected plant species to absorb and degrade contaminants taken up with groundwater
through their roots. To enhance the remediation of groundwater migrating toward Powell Creek, selected
plants and trees would be planted over the contaminant plume migration pathway. This alternative also
would include groundwater monitoring to evaluate the effectiveness of the remediation process,
implementation of administrative measures to prevent groundwater use until compliance with action levels
had been achieved, and performance of 5-year reviews to determine whether continued implementation of
this alternative is appropriate.
Alternative MM-8 would protect human health because it would remove organic contaminants from the
groundwater and prevent groundwater use until action levels have been met. This alternative would
achieve the RAOs and comply with ARARs. Significant, permanent, and irreversible reductions in
contaminant mobility, toxicity, and volume would occur through volatilization and plant uptake and
absorption. Groundwater monitoring would determine the rate and effectiveness of this reduction. Short-
term risks would be associated with the installation and operation of the air injection system and with the
performance of groundwater monitoring activities. These risks would be addressed through engineering
controls and health and safety procedures. Alternative MM-8 would achieve compliance with action levels
within approximately 30 years and would be" relatively easy to implement. The necessary equipment,
materials, and construction contractors are readily available. The present-worth cost would be
approximately $1,867,000.
2.7.2.4 Treatment Following Groundwater Extraction
Alternative MM-4: Pump-and-Treat with Discharge to Rowell Creek
049811/P 2-35 CTO0039
-------
Alternative MM-4 would consist of extracting the contaminated groundwater and vapors from the soil
followed by treatment in a facility that would be constructed on site. The treatment facility would remove
the organic contaminants from the groundwater by volatilization and adsorption on to activated charcoal
columns. The treated water would be discharged to Rowell Creek.
The extracted groundwater would be filtered to remove suspended solids, air-stripped, and percolated
through granular activated carbon (GAG) to remove organic COPCs. The need to treat of the air stripping
emissions would be determined at the conceptual design stage. The treated water would be discharged
to Rowell Creek. This alternative also would include groundwater monitoring to evaluate the effectiveness
of the remediation process, implementation of administrative measures to prevent groundwater use until
compliance with action levels had been achieved, and performance of 5-year reviews to determine
whether continued implementation of this alternative is appropriate.
Alternative MM-8 would protect human health because it would remove COPCs from the groundwater and
prevent groundwater use until action levels have been met. This alternative would achieve the RAOs and
comply with ARARs. Significant, permanent, and irreversible reductions in contaminant mobility, toxicity,
and volume would occur. Groundwater monitoring would determine the rate and effectiveness of this
reduction. Some short-term risks would be associated with the construction and operation of the
groundwater extraction and treatment system and with the performance of groundwater monitoring
activities. These risks would be addressed through engineering controls and health and safety
procedures. Alternative MM-4 would achieve compliance with action levels within approximately 9 years
and would be relatively easy to implement. The necessary equipment, materials, and construction
contractors are readily available. The present-worth cost would be approximately $2.970,000.
Alternative MM-5: Pump-and-Treat with Rpinjection for Enhanced Biodegradation
This alternative is similar to Alternative MM-4 with the exception that the treated water would be mixed
with nutrients and returned to the aquifer. It would remove contaminants in an above ground treatment
facility (as in Alternative MM-4) and enhances subsurface biodegradation (described under Alternative
MM-3). This alternative also would include groundwater monitoring to evaluate the effectiveness of the
remediation process, implementation of administrative measures to prevent groundwater use until
compliance with action levels had been achieved, and performance of 5-year reviews to determine
whether continued implementation is appropriate.
Alternative MM-5 would protect human health because it would remove COPCs from the groundwater and
prevent groundwater use until action levels have been met. This alternative would achieve the RAOs and
049811/P 2-36 CTO0039
-------
comply with ARARs. Significant, permanent, and irreversible reductions in contaminant mobility, toxicity,
and volume would occur. Ground water monitoring would determine the rate and effectiveness of this
reduction. Some short-term risks would be associated with the construction and operation of the
groundwater extraction and treatment system and with the performance of groundwater monitoring
activities. These risks would be addressed through engineering controls and health and safety
procedures. Alternative MM-5 would achieve compliance with action levels within approximately 12 years
and would be relatively easy to implement. The necessary equipment, materials, and construction
contractors are readily available. The present-worth cost would be approximately $4,072,000.
2.8 SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES
This section evaluates and compares the alternatives with respect to the nine criteria outlined in Section
300.430(s) of the NCR (U.S. EPA, 1990). These criteria are categorized as threshold, primary balancing,
or modifying. Table 2-3 lists and explains these evaluation criteria.
A detailed comparative analysis of the alternatives using the nine criteria was performed as part of the FS
(ABB-ES, 1997a). This analysis was used to identify preferred remedies for Site 3 in the Proposed Plan
(B & R Environmental, 1998). Table 2-4 presents a summary of the comparative analysis of alternatives.
2.9 SELECTED REMEDY
Based upon consideration of the requirements of CERCLA, the NCP, the detailed analysis of alternatives,
and U.S. EPA, FDEP, and public comments, a remedy was selected to address the contaminants in the
groundwater at Site 3. A combination of Alternatives MM-3 and MM-6 was selected for application.
In-situ Air Stripping of Source Area Groundwater by Air Sparging. - The volatile organic contaminants that
are present at concentrations that exceed cleanup goal concentrations will be reduced to the extent
necessary for natural attenuation to effectively occur. These contaminants will be removed by a process
of in-situ, subsurface volatilization, called air sparging, which uses clean air under pressure. Air sparging
also may enhance the removal of less volatile organics by stimulating biological activity. During pilot
studies prior to final design and implementation of the system, the VOCs will be captured in the gas phase
and their concentration measured to ensure that levels comply with Florida and U.S. EPA standards.
Requirements for vapor and off-gas treatment will be determined at that time. A monitoring plan will be
implemented to monitor and evaluate the effectiveness of air sparging and to determine the appropriate
time to begin site-wide natural attenuation.
049811/P 2-37 CTO0039
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TABLE 2-3
EXPLANATION OF EVALUATION CRITERIA
RECORD OF DECISION
SITE 3, OPERABLE UNIT 8
NAS, CECIL FIELD
JACKSONVILLE, FLORIDA
Criteria
Description
Threshold
Overall Protection of Human Health and the Environment. This criterion evaluates the
degree to which each alternative eliminates, reduces, or controls threats to human health
and the environment through treatment, engineering methods, or institutional controls(e.g.,
access restrictions).
Compliance with State and Federal Regulations. The alternatives are evaluated for
compliance with environmental protection regulations determined to be applicable or relevant
and appropriate to the site conditions.
Primary
Balancing
Long-Term Effectiveness. The alternatives are evaluated based on their ability to maintain
reliable protection of human health and the environment after implementation.
Reduction of Contaminant Toxicity, Mobility, and Volume Through Treatment. Each
alternative is evaluated based on how it reduces the harmful nature of the contaminants,
their ability to move through the environment, and the amount of contamination.
Short-Term Effectiveness. The risks that implementation of a particular remedy may pose
to workers and nearby residents (e.g., whether or not contaminated dust will be produced
during excavation), as well as the reduction in risks that results by controlling the
contaminants, are assessed. The length of time needed to implement each alternative is
also considered.
Implementability Both the technical feasibility and administrative ease (e.g., the amount of
coordination with other government agencies needed) of a remedy, including availability of
necessary goods and services, are assessed.
i
Cost. The benefits of implementing a particular alternative are weighted against the cost of
implementation.
Modifying
U.S. EPA and FDEP Acceptance. The final Feasibility Study and the Proposed Plan, which
are placed in the Information Repository, represent a consensus by the Navy, U.S. EPA, and
FDEP.
Community Acceptance. The Navy assesses community acceptance of the preferred
alternative by giving the public an opportunity to comment on the remedy selection process
and the preferred alternative and then responds to those comments.
049811 IP
2-38
CTO 0039
-------
TABLE 2-4
2
u>
09
SUMMARY OF COMPARATIVE EVALUATION OF ALTERNATIVES
RECORD OF DECISION - OPERABLE UNIT 8, SITE 3
NAS CECIL FIELD - JACKSONVILLE, FLORIDA
PAGE 1 OF 2
Alternatives
MM-1:
No Action
MM-2:
Enhanced
Biodegradation
MM-3:
In-situ Air Stripping with
Enhanced
Biodegradation
MM-4:
Pump and Treat with
Discharge to Rowell
Creek
MM-5:
Pump and Treat with
Rejection for Enhanced
Biodegradation
MM-6:
Natural Attenuation with
Institutional Controls
Threshold Criteria
Overall Protection of
Human Health & the
Environment
Would not protect human
health.
Would protect human
health through treatment
of contaminated
groundwater.
Would protect human
health through treatment
of contaminated
groundwater.
Would protect human
health through treatment
of contaminated
groundwater.
Would protect human
health through treatment
of contaminated
groundwater.
Would protect human
health by preventing
exposure to
contaminated
groundwater.
Compliance
with ARARs
&TBCs
No ARARs.
Chemical-
specific TBCs
would not be
met.
Would meet
ARARs.
Would meet
ARARs.
Would meet
ARARs.
Would meet
ARARs.
No ARARs.
Eventual
compliance with
chemical-
specific TBCs
would be
determined by
monitoring.
Primary Balancing Criteria
Long-Term
Effectiveness
Would not be
effective long-term.
Would be effective
long-term.
Would be effective
long-term.
Would be effective
long-term.
Would be effective
long-term.
Would be effective
long-term.
Reduction In
Contaminant Toxlcity,
Mobility. & Volume
Would not reduce
contaminant mobility.
Natural reduction in
toxicity and volume
would not be monitored
and would be unknown.
Would reduce
contaminant mobility.
toxicity and volume.
Would reduce
contaminant mobility,
toxicity and volume.
Would reduce
contaminant mobility,
toxicity and volume.
Would reduce
contaminant mobility,
toxicity and volume.
Would not reduce
contaminant mobility.
Natural reduction in
toxicity and volume
would be monitored.
Short-Term
Effectiveness
Would create no
short-term risks.
Would require 12
years to
complete
Would require 12
years to
complete.
Would require 9
years to
complete.
Would require 12
years to
complete.
Would require 62
years to
complete
Implementabllity
No action to
implement.
Would be easy to
implement.
Would be easy to
implement.
Would be easy to
implement.
Would be easy to
implement.
Would be relatively
easy to implement.
Cost
(Present Worth)
$427,000
$3,652,000
$3,322,000
$2,970,000
$4.072,000
$606.000
NJ
(!•>
tO
o
O
o
-------
TABLE 2-4
2
to
09
SUMMARY OF COMPARATIVE EVALUATION OF ALTERNATIVES
RECORD OF DECISION - OPERABLE UNIT 8, SITE 3
NAS CECIL FIELD - JACKSONVILLE, FLORIDA
PAGE 2 OF 2
Alternatives
Threshold Criteria
Overall Protection of
Human Health & the
Environment
Compliance
with ARARs
4TBCs
Primary Balancing Criteria
Long-Term
Effectiveness
Reduction In
Contaminant Toxiclty,
Mobility, & Volume
Short-Term
Effectiveness
Implementabillty
Cost
(Present Worth)
MM-7:
In-Situ Permeable
Reactive Well and
Hydraulic Barriers
Would protect human
health by treatment of
contaminated
groundwater.
Would meet
ARARs.
Long-term
effectiveness to be
evaluated.
Would likely reduce
contaminant mobility.
toxicity and volume of
VOCs.
Would require 62
years to
complete
Would be easy to
implement.
$2,170.000
MM-8:
In-situ Air Stripping with
Phytoremediation
followed by Natural
Attenuation
Would protect human
health by treatment of
contaminated
groundwater.
Would meet
ARARs.
Would be effective
long-term.
Would reduce
contaminant mobility,
toxicity and volume.
Would create
minimal and
manageable
short-term risks.
Would require 30
years to
complete
Would be easy to
implement.
$1,867.000
ro
J,
o
NOTE: The proposed remedy incorporates components of Alternatives MM-3 and MM-6.
ARAR = Applicable or Relevant and Appropriate Requirement
TBC = To Be Considered' Criteria
8
o>
(O
-------
Natural Attenuation of Downgradient Groundwater - Concentrations of organic and inorganic contaminants
exceeding groundwater cleanup goals in the treated source area and downgradient plume will be reduced
through natural attenuation processes, including biodegradation, dilution and dispersion, known to be
occurring at the site. Natural attenuation studies have previously been performed at the site and have
shown it to be effective in reducing contaminant levels. Additional groundwater modeling will be
performed during the remedial design, and a long-term monitoring plan will be implemented to further
evaluate and monitor the effectiveness of natural attenuation.
Implementation of Institutional Controls - Institutional controls will consist of administrative measures taken
to prevent exposure of human receptors to the groundwater of the surficial aquifer. Use of this
groundwater will be controlled through deed restrictions or land use plans. A formal request will be made
to the agency administrating the well installation permit program in Duval County to not issue permits for
installation of drinking water wells which would pump water from the surficial aquifer.
The goals of the institutional controls at Site 3 are to protect human health and the environment by (1)
preventing the exposure/consumption of groundwater that exceeds State and/or Federal MCLs, and State
groundwater guidance concentrations; (2) limiting exposure to surface and subsurface soils to prevent
unacceptable risk; (3) maintaining the integrity of remediation systems; and (4) protecting the current
morphological setting of Rowell Creek which is. aiding in the natural attenuation of groundwater
contamination.
2.10 STATUTORY DETERMINATIONS
The remedial alternatives selected for Site 3 are consistent with CERCLA and the NCP. The selected
remedy provides protection of human health and the environment, attains ARARs, and is cost-effective.
Table 2-5 lists and describes Federal and 8/ate ARARs to which the selected remedy must comply. The
selected remedy utilizes permanent solutions and alternative treatment technologies to the maximum
extent practicable, and satisfies the statutory preference for remedies that employ treatment that reduces
toxicity, mobility, or volume as a principal element. The selected remedy also provides flexibility to
implement additional remedial measures, if necessary, to address RAOs or unforeseen issues.
2.11 DOCUMENTATION OF SIGNIFICANT CHANGES
The Proposed Plan for Site 3 was released for public comment in January 1998. The proposed plan
identified the use of in-situ air sparging to reduce groundwater contaminants in the source area in
conjunction with natural attenuation and the application of institutional controls as the preferred alternative
for groundwater. The public was invited to comment during January and February 1998. No public
049811/P 2-41 CTO0039
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TABLE 2-5
2
8
SYNOPSIS OF FEDERAL AND STATE REGULATORY REQUIREMENTS FOR OU8 SITE 3
RECORD OF DECISION, OPERABLE UNIT 8 SITE 3
NAS CECIL FIELD, JACKSONVILLE, FLORIDA
PAGE 1 OF 2
Name and Regulatory Citation
Description
Consideration in the Remedial
Action Process
Type
Resource Conservation and
Recovery Act (RCRA)
Regulations, Identification and
Listing of Hazardous Wastes (40
CFR Part 261)
Defines the listed and
characteristic hazardous wastes
subject to RCRA. Appendix II
contains the Toxicity Characteristic
Leaching Procedure.
These regulations would apply
when determining whether or not a
waste is hazardous, either by
being listed or exhibiting a
hazardous characteristic, as
described in the regulations.
Chemical-Specific
Action-Specific
ts>
h
Endangered Species Act
Regulations (50 CFR Parts 81,
225,402)
Requires .Federal agencies to take
action to avoid jeopardizing the
continued existence of federally
listed endangered or threatened
species.
If a site investigation or remedial
activity potentially could affect
endangered species or their
habitat, these regulations would
apply.
Location-Specific
RCRA Regulations, Land Disposal
Restrictions (40 CFR Part 268)
Prohibit the land disposal of
untreated hazardous wastes and
provides standards for treatment
of hazardous waste prior to land
disposal.
Remedial actions that involve
excavating hazardous soil,
treating, and redepositing it require
compliance with land disposal
restriction (LDRs).
Action-Specific
Florida Hazardous Waste Rules
(FAC, 62-730)
Adopts by reference sections of
the Federal hazardous waste
regulations and establishes minor
additions to these regulations
concerning the generation,
storage, treatment, transportation
and disposal of hazardous wastes.
These regulations would apply if
waste is deemed hazardous and
needed be stored, transported, or
disposed.
Action-Specific
Safe Drinking Water Act (SDWA)
Regulations, Maximum
Contaminant Levels (40 CFR Part
131)
Establishes enforceable standards
for potable water for specific
contaminants that have been
determined to adversely affect
human health.
MCLs can be used as protection
for groundwaters or surface
waters that are current or potential
drinking water sources.
Chemical-Specific
-------
TABLE 2-5
2
to
00
SYNOPSIS OF FEDERAL AND STATE REGULATORY REQUIREMENTS FOR OU8 SITE 3
RECORD OF DECISION, OPERABLE UNIT 8 SITE 3
NAS CECIL FIELD, JACKSONVILLE, FLORIDA
PAGE 2 OF 2
Name and Regulatory Citation
Description
Consideration in the Remedial
Action Process
Type
Florida Groundwater Classes,
Standards and Exemptions (FAC,
62-520)
Designates the groundwaters of
the state into five classes and
establishes minimum "free from"
criteria. Rule also specifies that
Classes I & II must meet the
primary and secondary drinking
water standards listed in Chapter
62-550.
These regulations may be used to
determine cleanup levels for
groundwaters that are potential
sources of drinking water.
Chemical-Specific
ro
^
c*>
Florida Soil Cleanup Standards,
September 1995
Provide guidance for soil cleanup
levels that can be developed on a
site-by-site basis using the
calculations found in Appendix B
of the guidance.
These guidelines aid in
determining leachability-based
cleanup goals for soils.
Chemical-Specific Guidance
Florida Drinking Water Standards
(FAC. 62-550)
Adopts Federal primary and
secondary drinking water
standards.
These regulation apply to remedial
activities that involve discharges to
potential sources of drinking water.
Chemical-Specific
Florida Groundwater Guidance,
Bureau of Groundwater Protection,
June 1994.
Provides maximum concentration
levels of contaminants for
groundwater in the State of
Florida. Groundwater with
concentrations less than the listed
values are considered "free from"
contamination.
The values in this guidance should
be considered when determining
cleanup levels for groundwater.
Chemical-Specific Guidance
§
w
(O
Notes: OU = Operable Unit.
CFR = Code of Federal Regulations.
LDR = land disposal restriction.
FAC = Florida Administrative Code.
MCL = maximum contaminant level.
-------
comments were received during that time; therefore, no changes to the proposed remedy, as originally
identified in the Proposed Plan, have been made.
049811/P 2-44 CTO0039
-------
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ABB-ES (ABB Environmental Services. Inc.). 1992. Technical Memorandum for Supplemental Sampling.
Operable Units 1, 2. and 7. Naval Air Station (NAS) Cecil Field, Jacksonville, Florida. Prepared for
Southern Division, Naval Facilities Engineering Command (SOUTHNAVFACENGCOM). North Charleston,
South Carolina.
ABB-ES, 1994. Base Realignment and Closure Environmental Baseline Survey Report, NAS Cecil Field,
Jacksonville, Florida. Prepared for SOUTHNAVFACENGCOM, North Charleston, South Carolina
(November).
ABB-ES, 1995. Field Investigation Plan, Potential Sources of Contamination (PSC) 4, 6, 9, 12, 18. and 19.
NAS Cecil Field, Jacksonville, Florida. Prepared for SOUTHNAVFACENGCOM, North Charleston, South
Carolina (March).
ABB-ES, 1997a. Feasibility Study. Operable Unit 8, NAS Cecil Field, Jacksonville, Florida. Prepared for
SOUTHNAVFACENGCOM. North Charleston. South Carolina.
ABB-ES, 1997b. Baseline Risk Assessment, Operable Unity 8. NAS Cecil Field, Jacksonville Florida.
Prepared for SOUTHNAVFACENGCOM, North Charleston, South Carolina.
ABB-ES, 1997c. Remedial Investigation, Operable Unit 8, Site 3, Naval Air Station Cecil Field,
Jacksonville, Florida. Prepared for SOUTHDIVNAVFACENGCOM, North Charleston, South Carolina
(August).
I
B&R (Brown & Root) Environmental, 1998. Proposed Plan, Operable Unit 8, Site 3, Naval Air Station
Cecil Field, Jacksonville. Florida. Prepared for SOUTHDIVNAVFACENGCOM, North Charleston, South
Carolina (March).
Department of Defense, 1993. BRAC Cleanup Guidance Manual. Washington, D.C.
EE (Envirodyne Engineers, Inc.), 1985. Initial Assessment Study, Naval Air Station Cecil Field,
Jacksonville, Florida. Prepared for Navy Assessment and Control of Installation Pollutant Department,
Naval Energy and Environmental Support Activity. Port Hueneme, California (July).
049811/P R-1 CTO039
-------
Fairchild. R.W, 1972. The Shallow-Aquifer System in Duval County, Florida. Florida Bureau of Geology,
Report of Investigations No. 59. Tallahassee, Florida (January).
FDEP (Florida Department of Environmental Protection), 1994. "Cleanup Goals for Military Sites in
Florida." Memorandum from Ligia Mora-Applegate, Technical Review Section, Bureau of Waste Cleanup.
Tallahassee, Florida (July 5).
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