PB95-964034,
EPA/ROD/R04-95/250
March 1996
EPA Superfund
Record of Decision:
Homestead Air Force Base,
Operable Unit 1, FL
9/7/1995
-------
Homestead Air Reserve Base, Florida
Final
Record of Decision for
Operable Unit No. 1, Site FT-5,
Fire Protection Area No. 2
May 1995
-------
FINAL
RECORD OF DECISION
FOR
OPERABLE UNIT 1
SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR RESERVE BASE, FLORIDA
May 1995
Prepared for:
U.S. Army Corps of Engineers
Missouri River Division
Omaha District
Omaha, Nebraska
Prepared by:
Montgomery Watson
3501 North Causeway Boulevard, Suite 300
Metairie, Louisiana 70002
-------
RECORD OF DECISION
Operable Unit 1, Site FT-5,
Fire Protection Training Area No. 2
Homestead Air Reserve Base
Homestead, Florida
FDEP Facility No. 138521996
May 1995
Montgomery Watson appreciates the opportunity to work for the U.S. Army Corps of Engineers,
at the Homestead Air Reserve Base facility in Homestead, Florida. If you have any questions or
comments concerning this report, please contact one of the individuals listed below.
Respectfully submitted,
MONTGOMERY WATSON
Randall S. Luwe, P.G
Project Manager
/
A. &
Jerr/D. Gaccetta, P.G.
Project Engineer
-------
TABLE OF CONTENTS
Pag
SECTION 1.0 SITE NAME, LOCATION, AND DESCRIPTION 1
1.1 Operable Unit No. 1 Description 2
1.2 Regional Land Use 3
1.3 Regional Surface Hydrology 3
1.3.1 Regional Hydrogeologic Setting 4
1.4 Regional Site Geology and Hydrogeology 5
SECTION 2.0 HISTORY AND ENFORCEMENT ACTIVITIES 6
2.1 OU-I/Site FT-5 History 6
2.1.1 Past Site Usage 6
2.2 Base Enforcement History 7
2.2.1 CERCLA Regulatory History 7
2.3 Investigation History 8
2.3.1 IRP Phase I - Record Search 8
2.3.2 IRP Phase II - Confirmation/Quantification 9
2.3.3 IRP Phase III - Technology Base Development 10
2.3.4 IRP Phase IV- Additional Investigations 10
2.3.4.1 Phase IV - A Soil and Soil Vapor Investigation 11
2.3.4.2 Phase IV - A Sediment Investigation 12
2.3.4.3 Phase IV - A Surface Water Investigation 13
2.3.4.4 Phase IV - A Groundwater Investigation 13
2.3.5 1991 Remedial Investigation of Site FT-5/OU-1 14
2.3.6 1993 Remedial Investigation of Site FT-5/OU-1 15
2.4 Community Participation History 15
2.5 Scope And Role of Responsible Action 16
2.6 Summary of Site Characteristics 16
2.6.1 Nature and Extent of Contamination 17
2.6.2 Previous Field Investigations 17
2.6.2.1 Background Soil and Groundwater 17
2.6.2.2 Volatile Organic Compounds 18
2.6.2.3 Total Recoverable Petroleum Hydrocarbons/Cg-C20 19
2.6.2.4 Base/Neutral and Acid Extractable Compounds 20
2.6.2.5 Inorganics 21
2.6.2.6 Pesticides/PCBs 24
2.6.2.7 Total Organic Carbon 24
2.6.3 Summary 25
2.7 Summary of Site Risks 25
2.8 Selection of Chemicals of Potential Concern 26
2.9 Exposure Assessment 26
2.9.1 Exposure Point Concentration 26
2.9.2 Land Use 27
-------
TABLE OF CONTENTS
Page
2.9.3 Exposure Scenarios 27
2.9.4 Toxicity Assessment 27
2.9.5 Risk Characterization 28
2.9.5.1 Carcinogenic Risk 28
2.9.5.2 Total Risk 30
2.9.5.3 Risk from Lead Exposure 30
2.9.6 Chemicals of Concern and Remedial Goal Option 30
2.9.7 Uncertainties in the Risk Assessment 31
2.9.7.1 Ecological Risks 32
2.10 Description of Alternatives 32
2.10.1 Alternative 1 - No-Action with Groundwater Monitoring of
Contaminants for Migration and Attenuation 33
2.10.2 Alternative 2 - Access Restriction for Groundwater, Use
Restrictions for Soil, and Groundwater Monitoring of
Contaminant Migration and Attenuation 33
2.10.3 Alternative 3 - Access Restriction for Groundwater, Use
Restriction for Soil, Treatment of Rubble and Topsoil, and
Groundwater Monitoring of Contaminant Migration and
Attenuation 34
2.10.4 Alternative 4 - Access Restrictions for Groundwater, Use
Restrictions for Soil, Treatment and/or Disposal of Rubble Pile
and Topsoil, and Groundwater Monitoring of Contaminant
Migration and Attenuation 34
2.10.5 Alternative 5 - Treatment and/or Disposal of Rubble, Topsoil,
and Hot Spot Soils; In-Situ Biotreatment and Air Sparging of
Groundwater; and Groundwater Monitoring 35
2.11 Summary of Comparative Analysis of Alternatives 35
2.11.1 Overall Protection of Human Health and Environment 36
2.11.2 Compliance with ARARS 36
2.11.3 Long-term Effectiveness and Permanence 37
2.11.4 Reduction of Mobility, Toxicity, or Volume Through Treatment.... 37
2.11.5 Short-Term Effectiveness 37
2.11.6 Implementability 37
2.11.7 Cost 38
2.12 Selected Remedy 38
2.13 Statutory Determinations 39
2.14 Documentation of Significant Changes 40
-------
LIST OF TABLES
Table Follows
No. Title Page
2-1 Analytical Results of Phase IV-A Soil Samples Collected in 1989 From
Soil Borings at Site FT-5, Fire Protection Training Area No. 2,
Geraghty & Miller 12
2-2 Analytical Results of Phase IV-A Soil Samples Collected in 1989 From
Monitoring Well Borings at Site FT-5, Fire Protection Training Area
No. 2, Geraghty & Miller 12
2-3 Analytical Results of Phase IV-A Sediments Samples Collected in 1988
at Site FT-5, Fire Protection Training Area No. 2,
Geraghty & Miller 13
2-4 Analytical Results of Phase IV-A Grab Groundwater Samples Collected
in 1988 From Open Boreholes at Site FT-5, Fire Protection Training
Area No. 2, Geraghty & Miller 13
2-5 Analytical Results of Phase IV-A Groundwater Samples Collected in 1989
From Permanent Monitoring Wells at Site FT-5, Fire Protection Training
Area No. 2, Geraghty & Miller 14
2-6 Background Soil Concentrations 18
2-7 General Water Quality, Geraghty & Miller 19
2-8 Summary of Constituents Detected in Soil Samples Collected in 1993 at
Site FT-5, Fire Protection Training Area No. 2 18
2-9 Summary of Constituents Detected in Groundwater Samples Collected
in 1993 at Site FT-5, Fire Protection Training Area No. 2,
Montgomery Watson 19
2-10 Summary of Constituents Detected in Surface Samples Collected in 1993
at Site FT-5, Fire Protection Training Area No. 2, Montgomery Watson.... 19
2-11 Summary of Constituents Detected in Soil Samples Collected in 1993 at
Site FT-5, Fire Protection Training Area No. 2, Montgomery Watson 23
2-12 Comparison of Metals Detected in Sediment Samples Collected at
Site FT-5, Fire Protection Training Area No. 2, With Background
Concentrations, Montgomery Watson 23
2-13 Chemicals of Potential Concern at FT-5, Fire Protection Area No. 2,
Geraghty & Miller 26
2-14 Equations and Sample Calculations for Hypothetical Future Potable
Groundwater Exposure, Site FT-5, Fire Protection Training Area No. 2 27
2-15 Equations and Sample Calculations for Soil Exposure, Site FT-5,
Fire Protection Area No. 2 27
2-16 Equations and Sample Calculations for Wading Exposure at Site FT-5,
Fire Protection Training Area, Geraghty & Miller 27
2-17 Cancer Slope Factors, Tumor Sites and USEPA Cancer Classifications
for Constituents of Potential Concern, Site FT-5, Fire Protection
Training Area No. 2, Geraghty & Miller 28
2-18 Reference Doses for Constituents of Potential Concern, Site FT-5, Fire
Protection Training Area No. 2, Geraghty & Miller 28
in
-------
LIST OF TABLES
Table Follows
No. Title . Page
2-19 Risk-Based Remedial Goal Options for Soil Based on Potential Current
Base Worker Exposure - Site FT-5, Fire Protection Training Area No. 2,
Geraghty & Miller 31
2-20 Risk-Based Remedial Goal Options for Soil Based on Hypothetical
Future Adult Resident Exposure, Site FT-5, Fire Protection Training
Area No. 2, Geraghty & Miller 31
2-21 Risk-Based Remedial Goal Options for Soil Based on Hypothetical
Future Child Resident Exposure, Site FT-5, Fire Protection Training
Area No. 2, Geraghty & Miller 31
2-22 Comparative Analysis of Final Alternatives for Site FT-5, Fire Protection
Training Area No. 2, Geraghty & Miller 35
-------
LIST OF FIGURES
Figure Follows
No. Title Page
1 -1 Location of Homestead Air Reserve Base 1
1 -2 Base Location Map 2
1-3 Location Map, Site FT-5, Fire Protection Area No. 2 2
1 -4 Site FT-5, Fire Protection Training Area No. 2 Study Area 3
2-1 VOCs and TRPH Detected in Groundwater Samples Collected in
Groundwater Samples Collected During the 1989, 1991, and 1993 Field
Investigations Site FT-5, Fire Protection Training Area No. 2 19
2-2 Polynuclear Aromatic Hydrocarbons Detected in Soil/Weathered Rock
Samples Collected During the 1989, 1991, and 1993 Field Investigations,
Site FT-5, Fire Protection Training Area No. 2 20
2-3 Organic Compound Detected in Groundwater Samples Collected During
the 1989 , 1991, and 1993 Field Investigations, Site FT-5, Fire Protection
Training Area No. 2 20
2-4 Lead Concentrations Detected in Surface Soil/Weathered Rock Samples
Collected During the 1989, 1991, and 1993 Field Investigations,
Site FT-5, Fire Protection Training Area No. 2 21
-------
Homestead Air Reserve Base, Florida
Operable Unit No. 1
Fire Protection Training Area No. 2
Declaration for the Record of Decision
-------
DECLARATION STATEMENT
FOR THE
RECORD OF DECISION FOR OPERABLE UNIT NO. 1
SITE NAME AND LOCATION
Homestead Air Reserve Base
Homestead, Dade County, Florida
Operable Unit No. 1 - Site FT-5
Fire Protection Training Area No. 2 (former Site FPTA-2)
STATEMENT OF BASIS AND PURPOSE
This decision document presents the selected remedial action for the Fire Protection Training
Area No. 2 (Site FT-5), Operable Unit No. 1 (OU-1), at Homestead Air Reserve Base, in
Homestead, Florida. The selected remedial action is chosen in accordance with CERCLA, as
amended by SARA, and, to the extent practicable, the National Oil and Hazardous
Substances Pollution Contingency Plan (NCP). This decision document explains the basis
for selecting the remedial alternative for this Operable Unit. The information that forms the
basis for this remedial action is contained in the administrative record for Site FT-5/OU-1.
The selected alternative for OU-1 is access restriction for groundwater, use restriction for
soil, and groundwater monitoring for contaminant migration and attenuation. The State of
Florida, the U.S. Environmental Protection Agency (USEPA), and the U.S. Air Force
(USAF) concur with the selected remedy presented in this Record of Decision (ROD).
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 ROD, may present a current or potential
threat to public health, welfare, or the environment.
-i-
-------
DESCRIPTION OF THE SELECTED REMEDY
The response action selected in this document addresses through access restriction for
groundwater and institutional controls the health and environmental threats determined at this
site as exposure to soil and groundwater. It also requires zoning restriction by deed and
groundwater monitoring.
The major components of the selected remedy include:
Implementation of deed restrictions or restrictive covenants to limit usage of Site
FT-5/OU-1 to prevent schools, playgrounds, hospitals, and residential units from
being built at OU-1 to limit exposure to adults and children.
Eliminate and prevent the practice of continued rubble disposal at the site.
Restrict the placement of potable water wells into the contaminated groundwater
beneath the site.
Two years of semiannual groundwater monitoring followed by a review of the site to
assess the migration and attenuation of groundwater contaminants.
Five year review to determine whether the site remains protective of human health
and the environment and evaluate the need for further action, if required.
STATUTORY DETERMINATIONS
The selected remedy is protective of human health and the environment, complies with
federal and state requirements that are legally applicable or relevant and appropriate to
remedial action, and is cost effective. This remedy utilizes permanent solutions and
alternative treatment technologies to the maximum extent practicable for this site. The use of
institutional controls prevents human exposure to the soils and the contaminated groundwater
while semiannual groundwater monitoring would track the migration and/or attenuation of
groundwater contaminants. However, because treatment of the principal threats at the site
were not found to be practicable, this remedy does not satisfy the statutory preference for
treatment as a principal element of the remedy. The nature of the risk to human health is
minimal; and, with institutional controls, these risks do not pose a threat to human health or
the environment. This alternative meets the human health remedial action objectives (RAOs)
-u-
-------
by using institutional controls to prevent human exposure to chemicals of concern (COCs) in
the soil and groundwater. Therefore, the more cost effective remedial action is being
implemented based on evaluation of this risk and potential site usage.
Because this remedy will result in hazardous substances, pollutants, or other contaminants
remaining on-site above health-based levels, a review of the remedial action will be
conducted within 5 years after commencement of the remedial action to ensure that the
remedy continues to provide adequate protection of human health and the environment. The
review will be performed every five years thereafter.
UNITED STATES AIR FORCE
HOMESTEAD AIR FORCE BASE
By:.
Date:
Mr. Alan Olsen
Director, HQ AFBCA-DR
-in-
-------
Homestead Air Reserve Base, Florida
Operable Unit No. 1
Site FT-5, Fire Protection Training Area No. 2
Decision Summary for the Record of Decision
-------
DECISION SUMMARY
FOR THE
RECORD OF DECISION FOR OPERABLE UNIT NO. 1
1.0 SITE NAME, LOCATION, AND DESCRIPTION
Homestead Air Reserve Base (ARB) (formerly Homestead Air Force Base) is located
approximately 25 miles southwest of Miami and 7 miles east of Homestead in Dade County,
Florida (Figure 1-1). The main Installation covers approximately 2,916 acres while the
surrounding area is semi-rural. The majority of the Base is surrounded by agricultural land.
The land surface at Homestead ARB is relatively flat, with elevations ranging from
approximately 5 to 10 feet above mean sea level (msl). The Base is surrounded by a canal
(Boundary Canal) that discharges into Military Canal and ultimately into Biscayne Bay
approximately 2 miles east.
The Biscayne Aquifer underlies the Base and is the sole source aquifer for potable water in
Dade County. Within 3 miles of Homestead ARB an estimated 1,600 people obtain drinking
water from the Biscayne Aquifer, while 18,000 acres of farmland are irrigated from aquifer
wells (USEPA, 1990). All recharge to the aquifer is through rainfall.
Homestead Army Air Field, a predecessor of Homestead Air Reserve Base, was activated in
September 1942, when the Caribbean Wing Headquarters took over the air field previously
used by Pan American Air Ferries, Inc. The airline had developed the site a few years earlier
and used it primarily for pilot training. Prior to that time, the site was undeveloped. Initially
operated as a staging facility, the field mission was changed in 1943 to training transport
pilots and crews.
In September 1945, a severe hurricane caused extensive damage to the air field. The Base
property was then turned over to Dade County and was managed by the Dade County Port
Authority for the next eight years. During this period, the runways were used by crop dusters
and the buildings housed a few small industrial and commercial operations.
In 1953, the federal government again acquired the airfield, together with some surrounding
property, and rebuilt the Site as a Strategic Air Command (SAC) Base. The Base operated
-------
under SAC until July 1968, when it was changed to the Tactical Air Command (TAC) and
the 4531st Tactical Fighterwing became the new host. The Base was transferred to
Headquarters Air Combat Command (HQ/ACC) on June 1, 1992.
In August 1992, Hurricane Andrew struck south Florida causing extensive damage to the
Base. The Base was placed on the 1993 Base Realignment and Closure (BRAC) list and
slated for realignment with a reduced mission. Air Combat Command departed the Base on
March 31, 1994 with Air Force Reservists activated at the Base on April 1, 1994. The 482nd
Reserve Fighter Wing now occupies approximately 1/3 of the Base with the remaining
2/3 slated for use and oversite by Dade County.
1.1 OPERABLE UNIT NO. 1 DESCRIPTION
Operable Unit 1 (OU-l)/Site FT-5 occupies a general area approximately 11 acres in size and
is located in the southwestern portion of Homestead ARB, north of the approach zone to
Runway 05 and southwest of taxiway A (Figures 1-2). The Site FT-5/OU-1 area is bordered
by Campbell Drive to the west and northwest which is paved and oriented
northeast/southwest; an unnamed paved road to the south; and a drainage canal to the east
and northeast which typically contains water to a depth of one to two feet.
Beginning at the northern end of the site, the drainage canal flows from northwest to
southeast for approximately 525 feet. The canal then changes course by ninety degrees and
flows from the northeast to the southwest for approximately 780 feet until it reaches the
southern boundary of the site. Offsite, the canal turns southward and flows south to the
Boundary Canal which is located approximately 700 feet south of the site area. Remnants of
a circular concrete pad are located on the eastern part of the site where the drainage canal
forms a right angle.
The site is currently inactive (with respect to fire protection training activities and disposal
practices) and consists of an elevated fill/vegetation area, which is approximately 600 ft by
450 ft, located in the southern portion of the site (Figure 1-3). Lithologic logs indicate the
fill was approximately three to six feet thick in 1989. The elevated fill area is covered with
low vegetation, pine trees, limestone rubble, asphalt, and other construction debris. Because
the site is actively used as a rubble fill area by the Facility, the area occupied by the fill has
changed since 1989 and is continually changing. There is typically less than two-inches of
soil covering the limestone bedrock at the site (exclusive of the fill area). The limestone
-------
o
HENDRY COUNTY
COLLIER COUNTY
I 1
MONROE COUNTY I
PALM BEACH COUNTY
BOCA RATON J
BROWARD COUNTY
I ---- ,
LAUDERDALE
___J4
DADE COUNTY
S\\
(
i
r
PERRINEy BISCAYNE
I ( BAY
HOMESTEAD HOMESTEAD
EVERGLADES |_
NATIONAL '
PARK
-
0'
10 Mi
20 Mi
a.
5
i
I
I
APPROX. SCALE
HOMESTEAD AIR RESERVE BASE
HOMESTEAD, FLORIDA
LOCATION OF
HOMESTEAD AIR RESERVE BASE
FIGURE 1-1
-------
I
Source: USGS 7.5 minute
Topographic Quadrangles
Arsenteker, Homestead,
Goulds, and Perrine.
N
1000
2000
FEET
HOMESTEAD AIR FORCE BASE
HOMESTEAD, FLORIDA
BASE LOCATION MAP
FIGURE 1-2
-------
Housing Area
North Gate
Florida Gate
"\
FLORIDA
Homestead
AFB
_______ \. BOUGAINVILLE BOULEVARD
II
: II
!l
il
Y
II
j' ELLENDOAF
' STREET
cc:
oi i
SI BIGGS
v-° #
<-.> nX^
' ,
.*/
Military Canal
Ordnance Storage
FT-5
X
X /
'
Stormwater
Reservoir
Communication
Station
LEGEND
'Installation Boundary
Boundary Canal
Site Location
N
0 1000 2000
SCALE IN FEET
U.S. ARMY CORPS OF ENGINEERS
HOMESTEAD ARB
LOCATION MAP
SITE FT-5
FIRE PROTECTION AREA NO. 2
FIGURE 1-3
-------
bedrock is generally characterized as highly weathered and is penetrable with a split-spoon
formation sampler.
A drainage ditch is located south of the site just east of the intersection of the unnamed paved
road and the drainage canal bordering the site. This ditch collects runoff from the runway
area and flows from southeast to northwest into the drainage canal bordering the site. The
Ordnance Storage Area is located approximately 100 feet north of Site FT-5/OU-1 and
Taxiway A is located approximately 350-400 feet northeast of the site. In addition, two
buildings, 4071 and 4076, are located approximately 150 feet northeast of the drainage canal
which borders the upper part of the site (Figure 1-4).
1.2 REGIONAL LAND USE
The area adjacent to Homestead ARE including Site FT-5/OU-1, to the west, east, and south
within a half-mile radius is primarily composed of farmland and plant nurseries. Residential
areas are located within a half-mile to the north and southwest of the Base. Woodlands are
located approximately one-half-mile east of the facility and mangroves and marsh occur
adjacent to Biscayne Bay. The Biscayne National Park is located 2 miles east of Homestead
ARE; the Everglades National park is located 8 miles west-southwest of the Base; and the
Atlantic Ocean is approximately 8 miles east of the Base. OU-I/Site FT-5 is located in a
portion of the Base which will remain federal property under the auspices of the 482nd
Fighter Wing. Due to its proximity to the approach zone to Runway 05 and Taxiway A,
development of the site is not likely in the foreseeable future. Although the groundwater at
the site is not suitable for potable use, it is still classified as a potable source of drinking
water.
1.3 REGIONAL SURFACE HYDROLOGY
Surface hydrology at Homestead ARB, including Site FT-5/OU-1 is controlled by five main
factors: 1) relatively impermeable areas covered by runways, buildings, and roads;
2) generally, high infiltration rates through the relatively thin layer of soil cover; 3) flat
topography; 4) generally, high infiltration rates through the outcrop locations of the Miami
Oolite Formation; and 5) relatively high precipitation rate compared to evapotranspiration
rate. Infiltration is considered to be rapid through surfaces of oolite outcrop and areas with a
thin soil layer. Infiltration rates are accelerated by fractures within the oolite, as well as
naturally occurring solution channels. Precipitation percolates through the relatively thin
vadose zone to locally recharge the unconfmed aquifer.
-------
Elevated Fill/
VegetationArea
LEGEND
~~~~~ Boundary Canal
Drainage Canal
=^^ Road
Fence
Approximate Site Boundary
0 200 400
SCALE IN FEET
U.S. ARMY CORPS OF ENGINEERS
HOMESTEAD ARE
SITE FT-5
FIRE PROTECTION TRAINING AREA NO. 2
STUDY AREA
FIGURE1-4
-------
Natural drainage is limited because the water table occurs at or near land surface. The
construction of numerous drainage canals on Homestead ARE has improved surface water
drainage and lowered the water table in some areas. Rainfall runoff from within Homestead
ARE boundaries is drained via diversion canals to the Boundary Canal.
A drainage divide occurs within the Homestead ARE facility property, running from the
northern end of the facility, toward the center. Water in the Boundary Canal flows generally
south and east along the western boundary of the property, and south along the eastern
boundary, converging at a storm-water reservoir located at the southeastern corner of the
Base. Flow out of the storm water reservoir flows into Military Canal, which, in turn, flows
east into Biscayne Bay, approximately 2 miles east of the Base. Water movement is typically
not visible in the canals in dry weather due to the lowered water table and the very low
surface gradient (0.3 feet per mile) that exists at the Base.
1.3.1 Regional Hydrogeologic Setting
The regional hydrogeology in the southeast Florida area consists of two distinct aquifers: the
surficial aquifer system which consists of the Biscayne Aquifer and the Grey Limestone
Aquifer, and the lower aquifer, the Floridan Aquifer.
Biscayne Aquifer. The Biscayne Aquifer at Homestead ARB consists of the Miami Oolite,
Fort Thompson formation, and the uppermost part of the Tamiami Formation. In general, the
most permeable parts of the aquifer lie within the Miami Oolite and the Fort Thompson
Formation.
The Biscayne Aquifer underlies all of Dade, Broward, and southeastern Palm Beach
Counties. The Biscayne Aquifer is the sole source of potable water in Dade County and is a
federally-designated sole-source aquifer pursuant to Section 1425 of the Safe Drinking Water
Act (SDWA). The Biscayne Aquifer supplies drinking water to approximately 2.5 million
people within local communities. All recharge to the aquifer is derived from local rainfall,
part of which is lost to evaporation, transpiration, and runoff.
The Biscayne Aquifer has reported transmissivities ranging from approximately 4 to
8 million gallons per day per foot (mgd/ft) (Allman et al., 1979).
-------
Water-table contours indicate that under natural conditions, groundwater flows southeasterly
toward Biscayne Bay. The hydraulic gradient of the aquifer is approximately 0.3 ft/mile.
The water table at Homestead ARB generally is encountered within 5 to 6 feet of land
surface, but may occur at or near land surface during the wet season (May to October).
Fluctuations of groundwater levels and local variations in the direction of groundwater flow
are due to several factors: (1) differences in infiltration potential; (2) runoff from paved
areas; (3) water-level drawdown near pumping wells; (4) significant but localized differences
in lithology (e.g., silt-filled cavities); and (5) drainage effects of canals and water-level
control structures.
Floridan Aquifer. Underlying the low-permeability sediments of the Tamiami formation
and Hawthorn Group are the formations which constitute the Floridan Aquifer. The Floridan
Aquifer is composed of limestone and dolomite. It is under artesian pressure and water
levels in deep wells may rise 30 to 40 ft above ground surface. Groundwater within these
Miocene and Eocene age formations tends to contain dissolved constituents at levels
significantly above those recommended for drinking water. In view of the poor water quality
and the depth of water yielding zones (800 to 900 feet below land surface [bis]), the Floridan
Aquifer is of limited usefulness as a source of potable water supply in the study area.
1.4 REGIONAL SITE GEOLOGY AND HYDROGEOLOGY
The stratigraphy of the shallow aquifer system as determined from soil borings performed
during site investigations by Geraghty & Miller (G&M) indicate debris and fill in the area of
the rubble mound approximately three to six feet in thickness. The fill material has been
described as a gray to brown sand and silt with a high percentage of asphalt and concrete as
well as construction and demolition (C&D) debris. There is typically less than two-inches of
soil covering the limestone bedrock which consists of surficial weathered Miami Oolite
ranging in depth from 2 to 6 feet bis. The weathered limestone consists of a white to brown
semi-consolidated to consolidated oolitic limestone. This strata is underlain by consolidated
to semi-consolidated oolitic and coral limestone interbedded with coarse to fine sand and
clayey sand layers and lenses down to the total depth of borings (approximately 40 feet bis).
The Biscayne Aquifer is one of the most transmissive aquifers in the world and it underlies
Homestead ARB. A thin vadose zone, nominally less than 5 feet deep, overlays the
groundwater table at the site. As previously stated, the aquifer structure is a calcium
carbonate matrix. This lithology is know to have natural concentrations of target analyte list
(TAL) metals. In descending order by concentration, calcium, aluminum, iron magnesium,
-------
sodium, and potassium can be considered the primary metals of carbonate rock. The other
TAL metals occur in trace concentrations, less than 50 milligrams per kilogram (mg/kg).
The range and the standard deviations are not provided at this time. It should be expected
that, as precipitation infiltration and recharge take place, leaching of metal ions from the
weathered vadose zone and shallow unsaturated zone occurs. Regional data collected
suggest that concentrations of trace metals can be expected to be the greatest in the shallow
portion of the aquifer because of the proximity to the source (i.e., the weathering vadose
structure) and the decreasing retention time with decreasing depth of the saturated zone.
These observations support a hydrogeologic model in which the shallow portion of the
aquifer has a greater horizontal transmissivity than the vertical component during recharge at
the site to quantitatively differentiate horizontal and vertical components of the aquifer's
hydrologic conductivity. The possible presence of vertical solution zones is well
documented in the literature. The site-specific effects have not been fully investigated.
Nevertheless, the available data does not lead to the immediate conclusion that this is a
necessary task. The conceptual model that shallow groundwater is discharging to ditches
provided sufficient detail to arrive at the remedial decision for OU-1/Site FT-5.
2.0 HISTORY AND ENFORCEMENT ACTIVITIES
2.1 OU-1/SITE FT-5 HISTORY
2.1.2 Past Site Usage
The Fire Protection Training Area No. 2 operated from 1955 to 1972. The area was not
equipped with a liner or residual fuel collection system and it was not a routine practice to
first wet the burn area with water before applying flammable liquids (Engineering-Science,
1983). A variety of materials were burned at the site including JP-4, aviation gas, various
contaminated fuels, and waste liquids from base shops (oils, lubricants, solvents, etc.).
Extinguishing agents included water, carbon dioxide, aqueous film forming foam, and
protein foam. After training activities ceased at the site in 1972, construction debris was
disposed of by dumping and spreading it over a portion of the site. A mound of compacted
material approximately 3 to 6 feet (ft) above grade, with the dimensions of approximately
600 ft by 450 ft, is present in the southern portion of the site. Aerial photographs examined
from 1958, 1962, 1973, and 1983 indicate that several (at least four) fire training pits existed
in the location of the elevated fill area and at least one additional fire training pit was located
north of the elevated fill area (G&M, 1994).
-------
2.2 BASE ENFORCEMENT HISTORY
2.2.1 CERCLA Regulatory History
The Comprehensive Environmental Response, Compensation, and Liability Act of 1980
(CERCLA) established a national program for responding to releases of hazardous
substances into the environment. In anticipation of CERCLA, the Department of Defense
(DOD) developed the Installation Restoration Program (IRP) for response actions for
potential releases of toxic or hazardous substances at DOD facilities. Like the Environmental
Protection Agency's (EPA's) Superfund Program, the IRP follows the procedures of the
National Oil and Hazardous Substances Pollution Contingency Plan (NCP). Homestead
ARE was already engaged in the IRP Program when it was placed on the National Priorities
List (NPL) on August 30, 1990. Cleanup of DOD facilities is paid for by the Defense
Environmental Restoration Account (DERA), which is DOD's version of Superfund.
The Superfund Amendment and Reauthorization Act (SARA), enacted in 1986, requires
federal facilities to follow NCP guidelines. The NCP was amended in 1990 (see 40 CFR 300
et seq.) to implement CERCLA under SARA. In addition, SARA requires greater EPA
involvement and oversight of Federal Facility Cleanups. On March 1, 1991, a Federal
Facility Agreement (FFA) was signed by Homestead ARB (formerly Homestead AFB), the
USEPA, and the Florida Department of Environmental Protection (FDEP). The FFA guides
the remedial design/remedial action (RD/RA) process.
The purpose of the FFA was to establish a procedural framework and schedule for
developing, implementing, and monitoring appropriate response actions at Homestead ARB
in accordance with existing regulations. The FFA requires the submittal of several primary
and secondary documents for each of the operable units at Homestead ARB. This ROD
concludes all of the Remedial Investigation/Feasibility Study (RI/FS) requirements for Site
FT-5/OU-1 and selects a remedy for Operable Unit No. 1.
As part of the RI/FS process, Homestead ARB has been actively involved in the Installation
Restoration Program (IRP) since 1983 and has identified 27 Potential Sources of
Contamination (PSCs). Nine sites are in various stages of reporting under the RI/FS stage of
CERCLA; ten sites are being investigated in the Preliminary Assessment/Site Investigation
(PA/SI) stage of CERCLA, with three of these sites warranting no further investigation; one
-------
site has been closed under the Resource Conservation and Recovery Act (RCRA) guidelines:
and seven sites are being investigated under the FDEP petroleum contaminated sites criteria
(Florida Administrative Code 17-770). Additionally, a RCRA Facility Investigation (RFI) is
underway to evaluate numerous solid waste management units (SWMU) identified during a
RCRA Facility Assessment (RFA). The following PSCs are currently being investigated
according to the CERCLA RI/FS guidelines:
OU-1 - Fire Protection Training Area 2 (FT-5)
OU-2 - Residual Pesticide Disposal Area (OT-11)
OU-3 - PCB Spill C.E. Storage Compound (SS-13)
OU-4 - Oil Leakage Behind the Motor Pool (SS-8)
OU-5 - Electroplating Waste Disposal Area (WP-1)
OU-6 - Aircraft Washrack Area (SS-3)
OU-7 - Entomology Storage Area (SS-7)
OU-8 - Fire Protection Training Area 3 (FT-4)
OU-9 - Boundary Canal/Military Canal (SD-27)
Operable Unit No. 3, PCB Spill C.E. Storage Compounds has been closed out with the No
Further Action ROD in June 1994. All other CERCLA sites at Homestead ARB are
currently in various phases of the RI/FS process.
2.3 INVESTIGATION HISTORY
2.3.1 IRP Phase I - Record Search
An IRP Phase I - Records Search was performed by Engineering-Science, and is summarized
in their report, dated August 1983 (Engineering-Science, 1983). During the Phase I study,
sites with the potential for environmental contamination resulting from past waste disposal
practices were identified. Thirteen sites of potential concern were identified by reviewing
available installation records, interviewing past and present Facility employees, inventorying
wastes generated and handling practices, conducting field inspections, and reviewing
geologic and hydrogeologic data. In general, Phase I studies are used to determine if a site
requires further investigation.
The thirteen sites identified were ranked using the Hazard Assessment Rating Methodology
(HARM) developed by JRB Associates of McLean, Virginia, for the USEPA. HARM was
later modified for application to the Air Force IRP. The following factors are considered in
-------
HARM: (1) the possible receptors of the contaminants; (2) the characteristics of the waste;
(3) potential pathways for contaminant migration; and (4) waste management practices.
HARM scores for the sites ranked at Homestead ARE ranged from a high of 72 to a low of
7 out of 100. Eight of the thirteen sites were determined to have a moderate-to-high
contamination potential, one of which was the Fire Protection Training Area No. 2.
Additional monitoring was recommended for these sites. The remaining five sites were
determined to have a low potential for environmental contamination.
According to the IRP Phase I Report, Site FT-5/OU-1 received a moderate to high HARM
score of 66 due to the moderate quantity of liquid wastes used and the high potential for
contaminant migration in surface- and groundwaters of the site. Site FT-5/OU-1 scored high
as a potential migration pathway because of the extremely permeable nature of the soils and
underlying rock in the area and the proximity of the bordering drainage canal. Groundwater
samples were collected for analyses of pH, total dissolved solids (TDS), oil and grease, total
organic carbon (TOC), phenols, volatile halocarbons, and volatile aromatics.
2.3.2 IRP Phase II - Confirmation/Quantification
An IRP Phase II study was performed by Science Applications International Corporation
(SAIC), and was reported on in March 1986 (SAIC, 1986). The objectives of Phase II are to
confirm the presence or absence of contamination, to quantify the extent and degree of
contamination, and to determine if remedial actions are necessary. During the Phase II study,
additional investigations were performed at the eight sites recommended for monitoring in
the Phase I report, as well as two of the other thirteen originally-identified sites. The Fire
Protection Training Area No. 2 was included in this investigation.
During the Phase II investigation, one shallow monitoring well (1-13) approximately 18 ft
deep was installed southeast of the suspected contamination area at Site FT-5/OU-1 in
November 1984. Groundwater samples were collected from monitoring well 1-13 and fire
fighting Supply Well 248 located just northeast of Building 248 within the Ordnance Storage
Area. The groundwater samples were analyzed for oil and grease, total organic halogens
(TOX), and TOC. The upgradient well, the fire fighting supply well, contained
concentrations of TOX just above the detection limit. Monitoring well 1-13, installed
downgradient of the suspected location on this site, contained the highest TOX value
reported during the Phase II investigation. The specific compound(s) responsible for this
TOX value were not known but are probably related to chlorinated solvents contained in
wastes once used for training fire fighters or related to chlorinated pesticides used in the area
-------
(SAIC, 1986). No significant levels of TOC and biological oxygen demand (BOD) were
detected in the wells (SAIC, 1986). The exact location of the actual fire protection training
pit was not determined because it has been obscured by the rubble fill northwest of
monitoring well 1-13.
The Phase II report contained the following alternatives for additional investigation at this
site: (1) resample monitoring well 1-13 and analyze for halogenated organics to identify the
specific compounds involved in the contamination; (2) install a minimum of four additional
monitoring wells and collect groundwater samples for analysis of halogenated Priority
Pollutants to identify the compounds responsible for the elevated TOX value and to further
define the contaminated area; (3) collect surface water and associated sediment samples from
a minimum of four locations along the canal which runs east of the site and analyze samples
for halogenated Priority Pollutants to define the role of groundwater as a contaminant
pathway; and (4) use a combination of alternatives 2 and 3 above which would identify
specific contaminants, better define the plume, and characterize the surface water pathway.
The recommendations of the Phase II report however, included additional installation of
three monitoring wells and sampling of the new and existing monitoring wells for TOX and
organic priority pollutants.
2.3.3 IRP Phase III - Technology Base Development
The IRP Phase HI is a research phase and involves technology development for an
assessment of environmental impacts. There have been no Phase III tasks conducted at the
Base to date.
2.3.4 IRP Phase IV - Additional Investigations
The IRP Phase IV investigations consists of two areas of work activity. Phase IV-A involves
additional site investigations necessary to meet the Phase II objectives, a review of all
management methods and technologies that could possibly remedy site problems, and
preparation of a baseline risk assessment to address the potential hazards to human health and
the environment associated with the constituents detected at the site. Detailed alternatives
are developed and evaluated and a preferred alternative is selected. The preferred alternative
then is described in sufficient detail to serve as a baseline document for initiation of
Phase IV-B.
10
-------
An IRP Phase IV-A investigation was performed at Site FT-5/OU-1 by G&M during two
separate field programs, the first in 1988 and the second in 1989. The results of this
investigation are included in the report entitled "Draft Remedial Investigation/Endangerment
Assessment for Fire Protection Training Area No. 2 (FPTA-2), Homestead Air Force Base,
Florida," December 1990.
2.3.4.1 Phase IV-A Soil and Soil Vapor Investigation. In February 1988, during the
first field program, a soil vapor investigation was conducted at Site FT-5/OU-1. Twenty-one
soil borings (B-43 through B-63) were augured to a depth of approximately 8 ft below land
surface (bis) at Site FT-5/OU-1 in the area located adjacent to the elevated fill. After
completion, each borehole was sealed for approximately 12 hours prior to analyzing the
boring headspace with a Photovac TIP containing a photoionization detector (PID) and
calibrated to a 100 parts per million (ppm) isobutylene standard. Organic vapor
concentrations greater than ambient levels were detected in six soil borings. Five of the six
borings were located just east of the elevated fill area. On the basis of the soil vapor survey,
five additional soil borings were drilled to approximately 18 ft bis to install monitoring wells
HS-10 through HS-14. Continuous split-spoon formation samples were collected to the total
depth of each borehole to determine the physical and lithologic characteristics of the
soil/weathered limestone bedrock.
In March and April 1989, during the second field program, 20 additional soil borings were
drilled (TW-21 through TW-23, TW-31 through TW-34, FPTA2-SB1 through FPTA2-SB8,
FPTA2-MW1(SS1) through FPTA2-MW4(SS4), and FPTA2-DMW1) for a soil and soil
vapor investigation. Boreholes TW-21 through TW-23 and TW-31 through TW-34 were
drilled to install temporary monitoring wells. Boreholes TW-21 through TW-3, TW-31 and
TW-32 were drilled to eight ft bis. Boreholes TW-33 and TW-34 were drilled in the elevated
fill area to approximately seven ft bis. Soil samples were collected in each borehole at
two-foot intervals until the water table was encountered. The samples were analyzed with an
organic vapor analyzer (OVA), containing a flame ionization detector (FID), and a TIP.
Eight exploratory soil borings (FPTA2-SB1 through FPTA2-SB8) were drilled to aid in
evaluating the aerial extent of subsurface hydrocarbon constituents. Soil borings
FPTA2-SB1 through FPTA2-SB4 were drilled to four ft bis, soil borings FPTA2-SB5
through FPTA2-SB7 to eleven ft bis, and soil boring FPTA2-SB8 to eight ft bis. Split-spoon
soil samples were collected in each borehole and analyzed with an OVA and TIP. Additional
samples were collected from varying depths in the eight soil borings and submitted to Versar
11
-------
Laboratory, Inc., for analysis of volatile organic compounds (VOCs), base/neutral acid
extractable organic compounds (BNAs), Cg-C2o hydrocarbons, and total lead (Table 2-1).
Five additional soil boring locations (FPTA2-MW1[SS1] through FPTA2-MW[SS4] and
FPTA2-DMW1) were selected based on the results of the organic vapor analyses and
analyses of groundwater collected from temporary monitoring wells. These soil borings
were drilled to install five permanent monitoring wells. Split-spoon soil samples were
collected in boreholes FPTA2-MW1 through FPTA2-MW4 for chemical analyses by the
contracted laboratory. These soil samples were collected above the water table to determine
the presence or absence of subsurface hydrocarbon constituents in the vadose zone. Each
soil sample was analyzed for the following: VOCs, BNAs, Cg-C2o hydrocarbons, and total
lead. The results of these analyses are provided in Table 2-2. Split-spoon soil samples also
were collected from each monitoring well borehole for on-site organic vapor analysis with an
OVA and TIP.
The soil organic vapor analyses indicated elevated organic vapor concentrations using a TIP
which is a PID and an OVA which is a FID. The highest organic vapor concentrations were
detected in soil collected from depths greater than four ft bis at FPTA2-SB7, FPTA2-SB5,
TW-34, and TW-33 which are located in the central area of the elevated fill (G&M, 1990).
The maximum detected soil vapor concentrations for soils shallower than four ft bis were
detected at FPTA2-MW1, TW-22, and FPTA2-DMW1 which are located immediately east
of the elevated fill.
In the eight surface samples collected from 0 to 3 ft bis, BNAs, most of which were
polynuclear aromatic hydrocarbons (PAHs), were detected in five of the samples, Cg-C2o
hydrocarbons were detected in one sample, and lead was detected in six of the samples.
VOCs were not detected in the surface soil samples collected. In the 11 subsurface soil
samples collected from 3 to 10 feet bis, BNAs, most of which were PAHs, were detected in
ten of the samples, ethylbenzene and xylenes were detected in one sample, Cg-C2o
hydrocarbons were detected in two of the samples, and lead in nine of the samples. The
highest concentrations of total BNAs were detected in surface samples collected from 0 to 3
feet bis and subsurface samples collected from 3 to 8 feet in the elevated fill area.
2.3.4.2 Phase IV-A Sediment Investigation. In 1988, five sediment samples were
collected from the drainage canal adjacent to Site FT-5/OU-1 and were analyzed for VOCs,
BNAs, total recoverable petroleum hydrocarbon (TRPH), total lead, and BOD. The results
12
-------
TABLE 2-1
ANALYTICAL RESULTS OF PHASE IV-A SOIL SAMPLES COLLECTED IN 1080
FROM SOIL BORINQS AT STTE FT-«, RRE PROTECTION TRAINING AREA NO. 2
Homestead ARB, Florid*
LOCATION
SAMPLE DEPTH
CONSTITUENTS a/
VOLATILE ORQANICS
Ethylbenzene
Xyteoe (total)
BASBNEUTRAL EXTRACTABLES
Acanaphthene
Anthracene
BeruD(a)anthracena
BenzD(a)pyrene
Ben2D(b)fluoranthene
Banzo(g,h,l)perylen0
BenzD(k)fluoranthene
Chrysona
Dl-n-butylphthalale
Dlbenzo(a,h)anthracene
2,6-Dlnl(rololuene
bb(2-Ethylhexyl)phtnalate
Fhioranthena
Fhiorena
lndeno(1 ,2,3-cd)pyrene
Naphthalene
Phenanthrene
Pyrene
C8-C20 HYDROCARBONS (total)
TOTAL LEAD e/
UNITS
ug/kg
ug/Xg
ug/kg
mg/kg
FPTA2-SB1
0-2ft
< 29
< 29
< 633
< 633
< 633
< 633
< 633
< 633
< 633
< 633
1660 b/
< 633
< 633
< 633
< 633
< 633
< 633
< 633
< 633
< 633
< 12500
< 0.610
FPTA2-SB2
0-3ft
< 27
< 27
< 2870
(2390)
11100
12800
17700
14000
18200
17600
< 2870
4480
< 2870
< 2870
21100
< 2870
8790
< 2870
9600
18600
< 56900
78
FPTA2-SB3
0-2(1
< 30
< 30
< 694
< 694
< 694
< 694
< 694
< 694
< 694
< 694
< 694
< 694
< 694
< 694
< 694
< 694
< 694
< 694
< 694
< 694
< 13800
< 0.63
FPTA2-SB4
0-2(1
< 32
< 32
< 649
< 649
< 649
< 649
< 649
< 649
< 649
< 649
< 649
< 649
< 649
< 649
< 649
< 649
< 649
< 649
< 649
< 649
< 12900
23
FPTA2-SB5
S c/
43
84
6250
10500
16200
8290
8560
6520
11200
14800
< 3430
3800
< 3430
< 3430
31600
6990
4640
7400
53600
24000
114000
15
D d/
< 31
< 31
< 658
< 658
< 658
< 658
< 658
< 658
< 658
< 658
< 658
< 658
< 658
< 658
< 658
< 658
< 658
< 658
< 658
< 658
< 13000
< .600
FPTA2-SB8
S
< 27
< 27
12500
29400
54400
34200
41500
33900
45500
53500
< 8070
13900
< 8070
< 8070
113000
10800
23500
9340
152000
94500
< 160000
44
D
< 34
< 34
< 676
P55J
736
I546J
13491
< 676
< 676
774
< 676
< 676
< 676
< 676
1200
< 676
< 676
< 676
1240
954
< 13400
2.2
FPTA2-SB7
S
< 28
< 28
6400
17300
47800
40000
47300
23800
30300
48200
< 2910
6630
< 2910
< 2910
75000
7090
18500
3870
74400
56900
< 57600
5.6
D
< 32
< 32
< 641
1537]
653
(590]
15321
< 641
< 641
785
< 641
< 641
< 641
< 641
1320
< 641
< 641
(328]
1720
1060
23600
< 0.61
FPTA2-SB8
S
< 35
< 35
11500
19400
37200
23300
23100
14400
22500
34900
< 6940
7250
< 6940
< 6940
91500
11800
< 6940
8390
144000
62400
< 137000
14
D
< 32
< 32
821
1400
2410
1770
1940
< 641
2410
3300
|628] bf
< 641
653
|385]
5420
738
1390
I337J
6620
6590
< 12700
.700
a/ Constltutents not detected In any samples are not shown.
b/ Constituent delected In lab blank.
c/ S shallow sample collected In the 4-8 ft bis range.
d/ D deeper sample collected In the 6-10 ft bis range.
[) Value Is between Instrument detection limit and level of quantltatlon.
e/ Data originally reported In ug/kg.
Source: Qeraghty & Miller. Inc. (Q&M Project No. TF702.02)
f-.\TF702\FPTA2\RI\TABLE2-1 .XLS
-------
TABLE 2-2
ANALYTICAL RESULTS OF PHASE IV-A SOIL SAMPLES COLLECTED IN 1989
FROM MONITORING WELL BOREHOLES AT SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2
Homestead ARB, Florida
LOCATION
CONSTITUENTS eJ
VOLATILE ORGANICS
Ethylbenzene
Xylene (total)
BASE/NEUTRAL EXTRACTABLE ORGANICS
Acenaphthene
Anthracene
Benzo(a)anthracen0
Benzo(a)pyrene
Benzo(b)fluorBnthene
Benzo(g,hli)perylene
Benzo(k)fluoranthen0
Butylbenzlyphthalate
Chry serve
Di-n-butytphthalate
Dibenz(a,h)anthracene
bis<2-Ethylhexyl)phthalate
Ruoranthene
Ruorene
lndeno(1 ,2.3-cd)pyrene
Naphthalene
Phenanthrene
Pyrene
C8-C20 HYDROCARBONS (total)
TOTAL LEAD e/
UNITS
ug/kg
ug/kg
ug/kg
mg/kg
FPTA2-SS
FPTA2-MW
S
< 7720
< 7720
< 15600
< 15600
[11500]
[11 100)
< 15600
< 15600
< 15600
< 15600
16900
< 15600
< 15600
< 15600
22000
< 15600
< 15600
35400
17300
22000
2900000
45
FPTA2-SS2
FPTA2-MW2
So/
< 26
< 26
20200
56000
150000
84200
104000
56000
90000
< 13600
129000
< 13600
19000
< 13600
288000
14600
52500
[7610]
340000
230000
< 270000
32
Dd/
< 29
< 29
15700
25700
44900
21000
22800
24600
22600
< 14000
41900
< 14000
< 14000
< 14000
73600
[7750]
24300
[10700]
117000
77500
< 279000
23
FPTA2-SS3
FPTA2-MW3
S
< 26
< 26
[4320]
14600
54600
29900
36500
25000
35300
< 5050
53900
< 5050
6600
< 5050
133000
[3490]
16500
< 5050
79900
109000
< 100000
53
D
< 26
< 26
< 14400
15300
35600
24400
30800
28200
22300
< 14400
37100
< 14400
< 14400
< 14400
63800
< 14400
22400
< 14400
66400
69500
< 285000
25
FPTA2-SS4
FPTA2-MW4
S
< 28
< 28
34600
52000
89900
53700
< 14000
37600
< 14000
[11700] b/
97200
[8030] b/
< 14000
17300 b/
156000
35200
41600
[13400]
210000
143000
< 279000
8.6
D
< 29
< 29
21900
44100
77600
59800
75600
71500
70400
67600 b/
82900
< 14700
< 14700
[9180] b/
155000
27500
73300
[11400]
186000
127000
< 292000
34
a/ Constitutents not detected in any samples are not shown.
b/ Constituent detected in lab blank.
c/ S - shallow sample collected in the 0-3 ft bis range.
d/ D « deeper sample collected in the 3-6 ft bis range.
[ ] Value is between instrument detection limit and level of quantitation.
e/ Data originally in ug/kg
Source: Geraghty & Miller, Inc. (G&M Project No. TF430.01)
I:\TF702\FPTA2\RI\TABLE2-2.XLS
-------
of these analyses are presented in Table 2-3. Lead was detected in all sediment samples
collected.
2.3.4.3 Phase IV-A Surface Water Investigation. In 1988, five surface water samples
were collected from the same points along the drainage canal adjacent to Site FT-5/OU-1 as
the sediment samples and analyzed for VOCs, BNAs, TRPH, total lead, and BOD. Lead was
detected in all surface water samples collected and trichlorofluoromethane was detected in
one surface water sample. The concentrations of lead and trichlorofluoromethane, however,
were between the analytical method detection limit and the practical quantitation limit
(PQL). The practical quantitation limit is the lowest concentration of an analyte that can be
quantified by the laboratory, and is generally five to ten times greater than the method
detection limit which is the lowest concentration of an analyte that can be reliably detected
by the analytical method.
2.3.4.4 Phase IV-A Groundwater Investigation. Phase IV-A groundwater
investigations were conducted during both the 1988 and 1989 field programs. Grab
groundwater samples were collected from three open boreholes during the 1988 field
program to evaluate potential placement of permanent monitoring wells. Five permanent
monitoring wells (HS-10 through HS-14) were installed in 1988. Seven temporary
monitoring wells (TW-21 through TW-23 and TW-31 through TW-33) were installed during
the 1989 field program to evaluate potential placement of additional permanent monitoring
wells. Five additional monitoring wells (FPTA2-MW1 through FPTA2-MW4 and
FPTA2-DMW1) were installed in 1989. One temporary monitoring well (TW-33) was later
converted into permanent monitoring well FPTA2-MW5.
During the 1988 Phase IV-A field programs, grab groundwater samples were collected from
three soil borings (B-43, B-57, and B-58) and were analyzed by the contracted laboratory for
VOCs. Benzene, chlorobenzene, and ethylbenzene were used only to select locations for the
first five permanent monitoring wells. The results from these analyses are presented in
Table 2-4.
In February 1988, five shallow (approximately 18 ft deep) monitoring wells (HS-10 through
HS-14) were installed based on the results of the soil vapor investigation. In March of 1988,
groundwater samples were collected from the six permanent monitoring wells (HS-10
through HS-14, and 1-13) located at Site FT-5. These samples were analyzed for VOCs,
BNAs, TRPH, BOD, and total lead. Lead was detected in four of the six samples collected.
13
-------
TABLE 2-3
ANALYTICAL RESULTS OF PHASE IV-A SEDIMENT SAMPLES COLLECTED IN 198B AT SITE FT-S,
FIRE PROTECTION TRAINING AREA NO. 2
Homestead ARB. Florida
LOCATION
CONSTITUENTS a/
VOLATILE ORGANCS
BASE/NEUTRAL AND ACID EXTRACT ABLE ORGANICS
TOTAL LE AD cV
BODb/
TRPHc/
UNITS
u0*g
ug*8
mg*g
ug/Xo
ug/Kg
SED01
NO
NO
3O
NO
NO
SED02
NO
NO
28
ND
NO
SED03
ND
ND
44
ND
ND
SED04
ND
ND
22
ND
ND
SED05
ND
ND
17
ND
ND
a/ Constituents not detected In any camples are not shown.
b/ Biochemical oxygen demand.
c/ Total recoverable petroleum hydrocaitoons.
(] Value Is between instrument detection Imi and level o) quanUation.
ND Not detected. None of the constituents h this group were detected above their respective detection Emit*.
cV Data original)/ reported in ug/kQ.
Source: Geraghty & Miller, Inc. (G&M Project No. TF702.02)
I:\PROJ\TF702\FPT A2\R^ABLE2-3.XLS
-------
TABLE 2-4
ANALYTICAL RESULTS OF PHASE IV-A GRAB GROUND-WATER SAMPLES
COLLECTED IN 1988 FROM OPEN BOREHOLES AT SITE FT-6,
FIRE PROTECTION TRAINING AREA NO. 2
Homestead ARB, Florida
LOCATION
CONSTITUENTS a/
VOLATILE ORGANICS
Benzene
Chlorobenzene
Ethylbenzene
UNITS
ug/L
B-43
< 5
< 5
< 5
B-57
< 5
< 5
< 5
B-58
655
335
305
a/ Constituents not detected In any samples are not shown.
Source: Geraghty & Miller, Inc. (G&M Project No. TF702.02)
f:\PROJ\TF702\FPTA2\RI\TABLE2-4.XLS
-------
VOCs, BNAs, TRPH, and BOD were not detected in the monitoring wells. The results from
these analyses are presented in Table 2-5.
During the March and April 1989 Phase IV-A field program, seven temporary monitoring
wells (TW-21 through TW-23, and TW-31 through TW-34), four permanent shallow
monitoring wells (FPTA2-MW1 through FPTA2-MW4), and one permanent deep monitoring
well (FPTA2-DMW1) were installed at Site FT-5. Each temporary monitoring well (except
for TW-33 and TW-34) was installed to approximately 8 ft bis. Temporary monitoring well
TW-33, which was later converted to permanent monitoring well FPTA2-MW5, and TW-34
were installed through the hard fill to approximately 13 ft bis. The five shallow wells are
approximately 18 ft deep and the deep well is approximately 40 ft deep. The permanent
monitoring well locations were based on the results of the soil vapor survey conducted in
1989 and analyses of groundwater samples collected from temporary monitoring wells.
In March and April of 1989, groundwater samples were collected from six temporary
monitoring wells (TW-21 through TW-23, and TW-31 through TW-33) and eleven .
permanent monitoring wells (FPTA2-MW1 through FPTA2-MW4, FPTA2-DMW1, HS-10
through HS-14, and 1-13). These samples were analyzed for: VOCs, BNAs, total Cg-C2o
hydrocarbons (except TW-21 and TW-23), total lead, and dissolved lead. The temperature,
pH, and conductivity of each sample was measured at the time of sample collection.
In the 17 permanent and temporary monitoring wells sampled, VOCs including benzene,
ethylbenzene, toluene, chlorobenzene, and xylene were detected in six of the wells, BNAs
and lead were detected in four wells, and Cg-C2o hydrocarbons were detected in two of the
wells samples. The concentrations of toluene, xylene and chlorobenzene were between the
instrument detection limit and the practical quantitation limit.
2.3.5 1991 Remedial Investigation of Site FT-5/OU-1
In 1991, a remedial investigation (RI) was conducted at Site FT-5/OU-1 by G&M to evaluate
the current groundwater and soil quality with respect to the USEPA Target Compound List
(TCL) and Target Analyte List (TAL) for VOCs, BNAs, and metals. The 1991 RI included
the collection of four surficial soil samples (0 to 1 foot below the original soil horizon) and
12-groundwater samples from the site's existing monitoring wells.
14
-------
2.3.6 1993 Remedial Investigation of Site FT-5/OU-1
In 1993, G&M performed additional RI assessment activities to further evaluate the soil and
groundwater quality with respect to the USEPA TCL/TAL for VOCs, BNAs, organochlorine
(OC) pesticides/PCBs, and metals, utilizing EPA Contract Laboratory Program (CLP)
protocols and to fill data gaps from previous field investigations as well as evaluate any
impacts as a result of Hurricane Andrews. Eleven surficial soil samples were collected from
the site's existing monitoring wells, and five sediment and surface water samples were
collected in the drainage ditch which borders the site.
2.4 COMMUNITY PARTICIPATION HISTORY
The Remedial Investigation/Baseline Risk Assessment report and the Proposed Plan (PP) for
Homestead ARB Site FT-5/OU-1 were released to the public in April and November of
1994, respectively. These documents were made available to the public in both the
administrative record and an information repository maintained at the Miami-Dade
Community College Library.
A public comment period was held from November 8, 1994 to December 23, 1994 as part of
the community relations plan for Operable Unit No. 1. Additionally, a public meeting was
held on Tuesday, November 29, 1994 at 7:00 pm at South Dade High School. A public
notice was published in the Miami Herald and the South Dade News Leader on Tuesday,
November 22, 1994. At this meeting, the USAF, in coordination with USEPA Region IV,
FDEP, and Dade County Environmental Resource Management (DERM), were prepared to
discuss the RI results, the Baseline Risk Assessment, the Feasibility Study, and the Proposed
Alternative of access restriction for groundwater, use restriction for soil, and groundwater
monitoring for contaminant migration and attenuation as described in the PP. A response to
the comments received during this period is included in the Responsiveness Summary, which
is part of this ROD.
After .the close of the November-December 1994 public comment period, Alternative 5 was
added for consideration, making a total of five remedial alternatives given further
consideration subsequent to the Feasibility Study. This additional alternative includes the
biotreatment of contaminated groundwater.
Because of the addition of a fifth remedial alternative for consideration, the public comment
period was opened for thirty days, beginning March 14, 1995, and ending April 12, 1995,
15
-------
TABU 2-6
ANALYTICAL RESULTS OF PHASE (V-A GROUND-WATER SAMPLES COLLECTED IN 1MB
FROM PERMANENT MONITORING WELLS AT SITE FT-6,
FIRE PROTECTION TRAINING AREA NO. 2
Hom*sta«d ARB, Florida
LOCATION
CONSTITUENTS &/
VOLATILE ORGANICS
BASE/NEUTRAL AND ACID EXTRACTABLE ORGANICS
TOTAL LEAD
BODb/
TRPH
UNFTS
ug/L
ug/L
ug/L
mo/L
mg/L
HS-10
ND
ND
12.3]
< 2
< 0.21
HS-11
ND
ND
[1.8J
< 2
< 0.21
HS-12
ND
ND
11.2]
< 2
< 071
HS-13
ND
ND
< 1.0
< 2
< 020
HS-14
ND
ND
[2.7]
< 2
< 0.20
M3
ND
ND
< 1.0
< 2
< 0.21
aJ Constituents not detected in any samples are not shown.
bl Biochemical oxygen demand.
d Total recoverable petroleum hydrocarbons.
[ ] Value is between instrument detection ImS and level of quantitatlon.
ND Not detected. None oi the constituents In this group were detected above their respective detection imiu.
Source: Geraghty & Miller. Inc. (G&M Project No. TF7Q2.02)
f:\PROJYTF702\FPTA2\RI\TBL2-5.XLS
-------
to provide the public with an opportunity to comment on this added alternative prior to
issuance of the final Record of Decision. A notice was placed in the South Dade News
Leader on Tuesday, March 14, 1995. No comments were received during this additional
public comment period.
This record of decision document presents the selected remedial action for OU-1 at
Homestead Air Reserve Base, chosen in accordance with CERCLA, as amended by SARA
and, to the extent practicable, the NCP. The decision on the selected remedy for this site is
base on the administrative record.
2.5 SCOPE AND ROLE OF RESPONSIBLE ACTION
Currently, many areas within the boundaries of Homestead ARB are under investigation as
part of the designated NPL status of the Base. Each of the nine CERCLA investigation areas
has been designated as an individual Operable Unit (OU).
The U.S. Air Force with concurrence from the state of Florida and the USEPA, has elected to
define OU-1 as the Fire Protection Training Area No. 2. The remedial actions planned at
each of the OUs at Homestead ARB are, to the extent practicable, independent of each other.
This response action addresses the soil and groundwater contamination identified at OU-1.
For hypothetical future adult and child residents, both ingestion of contaminated soil and
groundwater pose a risk above the target risk range considered protective of human health by
USEPA and FDEP. The total site risks for Site FT-5/OU-1 were estimated above the USEPA
and FDEP health-based levels of concern for both current and future land use scenarios.
2.6 SUMMARY OF SITE CHARACTERISTICS
Fire protection training activities were conducted at Site FT-5/OU-1 from 1955 to 1972. A
variety of materials were burned at the site including JP-4, aviation gas, various
contaminated fuels, and waste liquids from base shops. The area was not equipped with a
liner or residual fuel collection system. Extinguishing agents included water, carbon dioxide,
aqueous film-forming foam, and protein foam. After training activities ceased at the site in
1972, construction debris was disposed of by dumping and spreading it over the site. A
mound of debris, approximately 6 feet high, presently covers an area 600 feet by 400 feet in
the southern portion of the site.
The following subsections summarize the nature and extent of the contamination identified at
16
-------
Site Ft-5/OU-l during investigations conducted from 1988 through 1993. The investigations
in 1991 and 1993 were conducted in accordance with the approved Facility Remedial
Investigation Work Plan (G&M), 1991. It should be noted that soil samples collected at Site
FT-5/OU-1 can be divided into three categories: soil/weathered limestone, limestone
bedrock, and fill.
2.6.1 Nature and Extent of Contamination
Remedial investigations have been performed at Site FT-5/OU-1 to evaluate the nature and
extent of contamination in 1991 and 1993. A detailed evaluation of the nature and extent of
contamination is presented in the RI report addendum prepared by G&M in 1994. In general,
the results of the sampling and analysis reveal that contamination in surficial soil/weathered
rock samples appears to be confined to the area of the fill and the immediate vicinity of
monitoring well FPTA2-MW1. PAH groundwater contaminants appear to be confined to the
elevated fill while BTEX contamination appears to be in the vicinity of monitoring well
FPTA2-MW1. Low levels of some constituents were observed in sediment and surface water
samples, but non at concentrations above regulatory limits or at levels of human health
concern.
2.6.2 Previous Field Investigations
Five field investigations have been performed to date at Site FT-5. The earliest investigation
was performed in 1984 by SAIC. One groundwater sample was collected and analyzed for
oil and grease, TOX, and TOC. The results of that field investigation recommended further
investigations. Additional investigations were conducted in 1988, 1989, 1991, and 1993.
Six groundwater samples and five surface water and sediment samples were collected in
1988 and analyzed for VOCs, BNAs, BOD, TRPH, and lead. Nineteen soil and seventeen
groundwater samples were collected in 1989 and analyzed for VOC, BNAs, total C8-C20
hydrocarbons and total lead. Four surface soil and 11 groundwaters samples were collected
in 1991. The surface soil samples were analyzed for VOCs, BNAs, and metals. The
groundwater samples were analyzed for VOCs, BNAs, TRPH, and metals. Finally, 11
surface soil, six groundwater, and five sediment and surface water samples were collected in
1993. All the samples were analyzed for VOCs, BNAs, OC pesticides, metals, and cyanide.
In addition, groundwater samples were analyzed for TDS, sediment samples were analyzed
for TOC and acid volatile sulfide, and surface water samples were analyzed for hardness.
17
-------
2.6.2.1. Background Soil and Groundwater. This section discusses the background
data that were obtained by G&M during the 1991 field investigation. This section also
discusses the general groundwater quality of the Biscayne Aquifer as well as the background
water quality beneath Site FT-5/OU-1. Because there are no chemical-specific ARARs for
soils, cleanup objectives are generally established by comparing the existing site conditions
to an established "background". This is especially important for metals, which can occur
naturally in high concentrations and over large areas.
Background levels for Homestead ARB soils at 0 to 2 ft bis, were based on soil samples
collected as background at four CERCLA sites and one RCRA site and are summarized in
Table 2-6. Also presented in Table 2-6 are the common ranges of inorganic constituents
found in soils in the eastern U.S., and typical values of both organic and inorganic
constituents found in soils in the eastern U.S., and typical values of both organic and
inorganic constituents found in uncontaminated soils.
Low levels of some pesticides have been found at several Homestead ARB sites. Pesticides
are not considered probable contaminants of site-specific activities at the fire training areas.
Past use of the Base as a crop dusting facility may explain the ubiquitous presence of
pesticides. Pesticides were analyzed for at OU-1, but were below health-based levels.
The groundwater in the Biscayne Aquifer has been characterized in a number of studies.
Analytical results from water samples collected from water supply wells, canal water (Radell
and Katz, 1991), the East Everglades (Waller, 1982), and from the Dade County Landfill
(McKenzie, 1983) indicate that all waters are calcium bicarbonate in character. The
groundwater is typically classified as "hard", but otherwise is of generally acceptable
chemical quality. Dissolved iron concentrations are naturally high in the Biscayne Aquifer
and commonly exceed the Florida secondary drinking water regulations. General mineral,
trace metal, and major water quality indicators are summarized in Table 2-7. Saline
groundwater is found in an area paralleling the coast and extends beneath the Base and Site
FT-5 (Klein and Waller, 1985).
2.6.2.2 Volatile Organic Compounds. Ethylbenzene and xylenes were detected at low
concentrations (less than 0.1 mg/kg) in one 1989 surface soil sample. In 1991, low
concentrations of six VOCs were detected in all four surface soil samples collected. The
compounds detected were methylene chloride, acetone, 2-butanone, tetrachloroethene,
chlorobenzene, and ethylbenzene. All VOC concentrations detected were below 1 mg/kg
with the exception of ethylbenzene. Ethylbenzene was detected at 16 mg/kg in
18
-------
TABLE 2-«
BACKGROUND SOIL CONCENTRATIONS
Compound
Volatile Organic Compounds (ug/kg)
Acetooe
Chlorobenzeoe
Metbylene Chloride
Average
Carbonate
Composition
Hem (1989)
Homestead ARB
Background
Soll(a)
0-2 ft bis
119.2
4
Typical Values
for Uncontamlnated
Soils (b)
(mg/kg)
Common
Range(c)
(mg/kg)
Average(c)
(mg/kg)
Total PAH* (ug/kg)
738.55
0.01 - 1.3 forest (d)
0.01 - 1.01 rural
0.06 - 5 .» urban
*- 336 road dust
Base/Neutral and Acid Extracuble Organic Compounds (ug/kg/dw)
Acenaphtbeoe ND
Benzo(a)aiithracene 67
Benzo(a)pyrene 66
Benzo(b)fluarantbeoe 69
Benzo(gJU)perylene 44
Bcnzo10.000
2-10(e)
-------
TABLE 2-7
GENERAL WATER QUALITY
HOMESTEAD AIR RESERVE BASE
STTEFT-5
Parameter
(Concentrations in micrognms per
liter)
Aluminum
Antimony
Arsenic
Barium
Beryllium
rVjrpiiim
Chromium
Cobalt
Copper
Leld
Mercury
Nickel
Selenium
Silver
Thallium
Vanadium
Zinc
(Concentrations in milligrams per
liter)
Calcium
Magnesium
Manganese
Iron
Potassium
Sodium
Bicarbonate
Chloride
Sulfate
Nitrate
pH
TDS
TOC
Supply WeUs"
Median
-
.
-
24
.
.
10
07
92
3.7
0.014
0.312
1.8
22
272
36
17
0.13
7.13
350
14
Range
-
-
BDL-300
.
-
BDL-90
-
BDL-31
BDL-604
-
.
.
.
.
.
-
27 - 190
0.9 - 53
BDL-0.150
BDL-21
0.23 - 16
2.8 - 530
66-610
5.0-980
0.1 - 160
<0.04 - 32
6.35 - 7.80
111-2,130
0.8 - 74
Canal
Median
-
-
36
-
-
3
-
3
7
-
-
.
-
.
.
-
84
8.8
0.006
0.10
2.5
44
276
78
14
0.04
7.62
422
21
Water"
Range
-
-
-
5- 100
-
-
1-40
-
1-80
1-72
-
-
-
-
.
.
-
74-100
2.9 - 32
0.001-0.041
0.004-1.24
1.6-6.6
23 - 120
224-415
36- 190
4.3 - 53
0.01-0.19
7.27 - 7.85
323 818
5.0-46
Ea*tStudyb
Range
Oe-70
-
0-2
0-100
.
0-3
10-20
-
0-11
0-21
0.5
-
0
0-1
.
.
10-40
93 - 130
10-26
10-20
0.75 - 5.0
6.2 - 16
54 - 220
210-284
120 - 450
58-99
0.00 - 0.05
7.1 - 7.4
629 - 846
0-13
West
Studyb
Range
-
-
1-7
-
-
1-9
10-20
-
0-2
0- 10
0.5 - 0.5
2-22
.
0-60
.
.
-
72-84
2.8 - 4.0
0.1 -0.3
0.4 - 1.6
0.2 - 9.5
8.6-13
230-440
15-20
2.1- 14
0.0 - 0.76
6.7 - 8.0
236 - 288
0-83
Site FT-5d'f
Background Well
11-11
1,500
<50
26
110
<0.5
<5.0
<2,000
<10
<25
9.4
0.46
<400
<250
<10
<50
87
57
91 - 6,300
1.7-16
0.16
0.017
1.4-19
6.3-21
.
.
.
.
.
.
-
Site FT-5d»f
Investigation Wells
Range
<200- 6.100
<50
<10- 12.1
<10-50.8
<0.5
<5.0
<50to<1.000
<10
<25
<5.0 - 34
<0.20
<40
<10 to <50
<10
<10
<10- 19
<20-490
89-1.200
1.6-4.5
<0.010-0.05
<0.05 - 2.6
<1 0 - 6 1
8.3 - 319
.
.
.
.
.
.
-
8 -Radell and Katz, 1991
b - Waller, 1982
c McKenzie
From: Geraghty & Miller, 1993a
a - Geraghty A Miller. 1993a
e - Compounds not detected in this study were reported as zero
' - Insufficient dala for ion balance verification
-------
FPTA2-SL-10. Low concentrations of six VOCs were detected in 10 of the 11 surface soil
samples collected in 1993 (Table 2-8). The VOC compounds detected are commonly used as
solvents or degreasers and may have been disposed of at Site FT-5; however, several
oxygenated VOCs are also common laboratory contaminants. Detections of 2-butanone.
methylene chloride, and acetone (detected at low levels in 10 of the 11 samples) may be the
result of laboratory contamination.
No VOCs were detected in the six groundwater samples collected in 1988. VOCs were
detected in four of the 17 groundwater samples collected in 1989 (Figure 2-1). Benzene was
detected in three of the samples at concentrations ranging from 8.7 to 212 micrograms per
liter (u.g/L). VOCs were detected in two of the 11 samples collected in 1991 (Figure 2-1).
Benzene was detected in one of the 1991 samples at a concentration of 2.6 u.g/L.
VOCs were detected in one of the six groundwater samples collected in 1993 (Figure 2-1,
Table 2-9). Benzene was detected in FPTA-MW-1 at a concentration of 2 Hg/L and its
duplicate sample FPTA-MW9001 at a concentration of 1 fig/L. This is above and at the state
maximum contaminant level (MCL) of 1 |J.g/L. However, this well contained benzene
concentrations of 2.6 fig/L in 1991 and 72 ng/L in 1989. The overall benzene, toluene,
ethylbenzene, and xylenes (BTEX) concentration detected in FPTA2-MW1 and
FPTA2-MW9001 (2 and 1 |ig/L) in 1993 are approximately 5 and 10 times lower than the
concentration of BTEX detected in 1991 (10.9 |J.g/L) and approximately 50 times lower than
the concentration of BTEX detected in 1989 (102 u.g/L). The decrease in BTEX in the
groundwater at Site FT-5/OU-1 suggests that the BTEX is attenuating naturally, possibly
from biodegradation (G&M, 1993a).
VOCs were not detected in the 1988 sediment or surface water samples. VOCs were also not
detected in the 1993 sediment samples. Low concentrations (<10 JJ.g/L) of four VOCs
(bromodichloromethane, 2-butanone, methylene chloride, and 1,1,1-trichloroethane) were
detected in the 1993 surface water samples (Table 2-10). All the VOCs detected in the
samples were at concentrations between the instrument detection limit and the practical
quantitation limit: and 2-butanone and methylene chloride are probably laboratory
contaminants.
2.6.2.3 Total Recoverable Petroleum Hydrocarbons/Cg-C20. Petroleum hydrocarbons in
the Cg-C20 range were detected in two of the 1989 surface soil samples at concentrations of
114 mg/kg and 2,900 mg/kg. Soil samples collected during the 1988, 1991, and 1993
investigations were not analyzed for Cg-C20 hydrocarbons.
19
-------
LEGEND
TRPH/C8-C20
VOCS
NA
ND
J
1993
FPTA2-MW1 1999 1991 1993 (Dup)
TRPH/Cg-CgQ
VOCs
Benzene
Chtorobenzone
Ethy benzene
Toluene
Xytene
1.5
72
ND
25
[13]
[17]
27
2.6
ND
ND
1.3
ND
NA
2 J
4 J
ND
ND
ND
NA
1J
3J
ND
ND
ND
MW5
Elevated FHV
MW4 Vegstatton Area
FPTA2-MW3 1989 1991
TRPH/Cg-C^
VOCs
1.0
ND
6.66
ND
MW3
L
ND
FPTA2-MW4 1989 1991 1993
TRPH/C8-C20
VOCs
Toluene
ND
[3.7]
<1.0
ND
ND
ND
Drainage Ditch
Groundwater Sampling Location
Total Recoverable Petroleum Hydrocarbons/C8-C2o Hydrocart>ons
Volatile Organic Compounds Detected Above
Slate or Federal MCLs
Not Analyzed
Not Detected Above Instalment Detection Limits
Positive result has been classified as qualitative due to
deficiencies in one or more quality control measures
All Results in Micrograms per Liter (pg/L)
' Paved Road
~ Drainage Canal
Reference: G&M. 1994a '
200
SCALE IN FEET
To
Boundary
Canal
U.S. ARMY CORPS OF ENGINEERS
HOMESTEAD ARB
VOCs AND TRPH DETECTED IN
GROUNDWATER SAMPLES COLLECTED DURING
THE 1989, 1991, AND 1993 FIELD INVESTIGATIONS
SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2
FIGURE 2-1
-------
TABLE 2-8
SUMMARY OF CONSTITUENTS DETECTED IN SOIL SAMPLES COLLECTED
IN IWJ AT SITE FT-S. FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR FORCE BASE, FLORIDA
(Puge 1 of 6)
G&M I.D. FPTA2-SL-OOI3 FPTA2-SL-90I3 FPTA2-SL-OOI4 FTTA2-SI^«OI5
Average Carbonate Homestead AFB Savannah I.D. 40688-7 40688-12 40688-8 40688-9
Coapodtloa Background/b Dale Sampled 2/4/93 1/4/93 2/4/93 2/4/93
Parameter Hem (1*89) Average Range % Solldj 80 SO 88 85
Volatile Orgaok Compound! (jg/Vg dw)
Methylene Chloride 4 4.0-O2 (2.100) U < 1.600
Acetone 119.2 8.3-230.0
12.000
2-Butanone ND
-------
TABLE 2-8
SUMMARY OF CONSTITUENTS DETECTED IN SOIL SAMPLES COLLECTED
IN 1993 AT SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR FORCE BASE, FLORIDA
(Page 2 of 6)
Parameter
Organochlortae Pedklde*/PCBi Og/kg dw)
Hcpuchlor Epoxide
4,4'-DDE
4,4'-DDD
MrtaU (mg/kg dw)
Aluminum
Arsenic
Barium
Calcium
Chromium
Copper
Iron
Lead
Magnesium
Manganese
Silver
Sodium
Vanadium
Zinc
Cyanide (mg/kg dw)
Average Carbonate
Cwnportloo
Hem (1989)
ND
ND
ND
8,970
1.8
30.0
272,000
7.1
4.4
8.190
16.0
45.300
842.0
0.19
393
13
16
ND
G&M I.D. FPTA2-SL-0013
Homestead AFB Savannah I.D. 40688-7
Background/b Date Sampled 2/4/93
Average Range % Solldi 80
ND
ND
ND
2,400
1.6
42.9
345.000
11.5
ND
1,650
4.1
1.050
23.0
ND
555
ND
20
NA
<4.7-«r5.8 < II
<4.7-<5.8 34 "
<4.7-<5.8 270
2,100-2.700 836
-------
TABLE 2-8
SUMMARY OF CONSTITUENTS DETECTED IN SOIL SAMPLES COLLECTED
IN 1993 AT SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR FORCE BASE, FLORIDA
(Page 3 of 6)
Parameter
Volatile Organic Compounds 0>g/kg dw)
Melhylene Chloride
Acetone
2-Bulanone
Bromodichloromelhane
Benzene
Chlorobenzene
Xyleno
Bate/Neutral and
Acid Eitractable Compound! Oig/kg dw)
3-Methylphenol/4-Melhylpheno(m-.p-Cresol)
Naphthalene
2-Mcthylnaphthalene
Acenaphihylcne
3-Nilroaniline
Acenaphlhene
Dibenzofuian
Fluorene
Penlachlorophcnol
Phenanihrene
Anthracene
Carbazole
Di-n-buiylphlhalaie
Fluoranihene
Pyrene
Butylbenzylphlhalale
Benzo(i)anlhracene
Chrysene
Benzo(b)nuoranthene
Benzo(k)nuoranlhenc
Benzo(a)pyrene
lndeno(l.2.3-cd)pyrcne
Dibenz(a,h)anihracene
Benzo(g.h,i)perylene
Average Carbonate
Hem (1989) Averac
4
119.2
ND
ND
ND
3.8
ND
NA
50
84
ND
ND
ND
ND
ND
ND
50
ND
ND
52.4
49.1
16
67
79
69
66
66
45
17
44
C4M I.D. FPTA2-SL-0016 FPTA2-SL-00I7 FPTAJ-SL-WIg FPTA2-SlrOOI9
Homestead AFB Savannah I.D. 40688-10 40688-11 40688-13 40688-14
Background/b Dale Sampled 2/4/93 2/4/93 2/4/93 2/4/93
e Range % Solid. (9 88 83 83
40-
-------
TADLE2-8
SUMMARY OF CONSTITUENTS DETECTED IN SOIL SAMPLES COLLECTED
IN 1993 AT SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR FORCE BASE. FLORIDA
(Page 4 of 6)
GAM I.D. FPTA2-SL-4016
Avenge Carbonate Hometfead AFB Savannah I.D. 40688-10
CompodUon Background/fa Dale Sampled 2/4/93
Parameter Hem (1989) Average Range % Solid* 89
Organochlorine Festkldet/PCBi Ug/kg dw)
Hepuchlor Kpoxide NU NO <4J-<3.8 R7J J
4,4'-DDE ND NO <4.7-<5.8 < 370
4,4'-DDD ND ND <4.7-<5.8 < 370
MeUb (mg/kg dw)
Aluminum 8.970 2.400 2,100-2,700 1.440
Arsenic 1.8 1.6 <1. 1-1.6 "J.'J
Barium 30.0 42.9 3.8-80 < 2.2
Calcium 272.000 345.000 320,000-370.000 260,000
Chromium 7.1 11.3 11-12 "' IJ.'I
Copptr 4.4 ND <2./-
-------
TABLE 2-8
SUMMARY OF CONSTITUENTS DETECTED IN SOIL SAMPLES COLLECTED
IN 1993 AT SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR FORCE BASE, FLORIDA
(Pyge 5 of 6)
Parameter
Volatile Organk Compounds (/ig/kg dw)
Mcthylcnc Chloride
Acetone
2-Buunone
Bromodichloromethane
Benzene
Chlorobenzene
Xylenes
Average Carbonate
Composition
Homestead AFB
Background/b
Hen (1989) Average Range
4
119.2
ND
ND
ND
3.8
ND
4.0- < 12
8.3-230.0
-------
TAULE2-8
SUMMARY OF CONSTITUENTS DETECTED IN SOIL SAMPLES COLLECTED
IN 1993 AT SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR FORCE BASE, FLORIDA
(Page < of 6)
Parameter
Avenge Carbonate
CompofUlon
Hem (1989)
G&M I.D. FPTA2-SL-M20
Homestead AFB Savannah I.D. 40688-15
Background/b Dale Sampled 2/4/93
Average
Range % SoUdi 85
FPTA2-SL-W2I FPTA2.SL-0022 FPTA2-SU0023
40688-li 4068J-I7 40688- IS
2/4/93 2/4/93 2/4/93
87 83 89
Orgaoochlorloe Pe««lclde»/PCBj (jg/kg dw)
Heplachlor Eponidc
4,4'-DDE
4,4'-bbD
Metali (mg/kg dw)
Aluminum
Arsenic
Barium
Calcium
Chromium
Copper
Iron
Lead
Magnesium
Manganese
Silver
Sodium
Vanadium
Zinc
Cyanide (mg/kg dw)
Notes:
Pg/kg micrograms per kilogram
mg/kg milligrams per kilogram
< Analyle was not detected at
ND
ND
ND
8.970
1.8
30.0
272,000
7.1
4.4
8.190
16.0
45,300
842.0
0.19
393
13
16
ND
or above the indicated concentration.
J Positive result has been classified as qualitative due to deficiencies in one or
ND
ND
ND
2,400
1.6
42.9
345.000
11.5
ND
1,650
4.1
1,050
23.0
ND
555
ND
20
NA
<47-<5.8 < 2
<47 <5.8 < 3.9
<4.7-<5.8 < 3.9
2.100-2.700 580
-------
TABLE 2-9
SUMMARY OF CONSTITUENTS DETECTED IN GROUNDWATER
SAMPLES COLLECTED IN 1993 AT
SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2
Homestead Air Rcserre Base, Florida
(Page 1 of 3)
Ptruiftor
VOIATOI ORGANIC COMPOUNDS (at/I*
B*ni«M
CUmotNounB
MetlqrltBt Chloriik
SBMIVOLATILS ORGANIC COMPOUNDS (o|O.)t
MtkUqrkii|ibthikOT
J-M«liylpbMX)V4-Metb,lj*nio»(n>-4vO«l)
AotPlpOlnUM
Aootphffiylcot
Antincrat
Ni(2-EtliyU>ajr|)pbUulil*
Bilylbcul^xhiliu
Ctrbuok
Dt-D-talrfeMhihu
DI-o-oc
-------
TABLE Z-9
SUMMARY OF CONSTITUENTS DETECTED IN GROUNDWATER
SAMPLES COLLECTED IN 1993 AT
SITE n-6, FIRE PROTECTION TRAINING AREA NO. 2
Homestead Air Reserve Bast, Florida
(Page 2 of 3)
PtruntUr
VOLATILE ORGANIC COMPOUNDS (H/U
Benzeoe
Chtoobenieoe
florid.
Crowd-
W.UT
Guldino
Coounlrition*
ID
lk
10
FAC
17-770
florldi
lb
NS
KPA
DrinUni
W«t*r
SUndvdt
5*
NS
EPA
Mud mum
ConUmliuot
Ur.l Got!
NS
NS
C*M LD. fPTAJ-
Smnub LD. MW-4
Out Suapkd 40MM.1
1/10(93
< 10
< 10
FPTArMWJ
4V743-3
2/W93
< 10 U <
< 10 I) <
I
FTTAJ-
DMW1
40*04-3
1/10/93
10
10
KqulpaMl
Bl«ik
4O8M-*
l/IO/»3
U < 10
U < 10
J
Melbyteat Cbloride
SKMTVOLATILI ORGANIC COMPOUNDS (n^L):
NS
2-Melbybupbtl»lcDc
3-MMbylpbRX>l/4-Mclliylpt)ei»l(m-,p-Crnol)
Acenapbibcoe
Aceupblbykne
AottiriotiK
bfi(2-EUiyU>uyl)pbU>iUu
BglylbrailpbUuUU
Cubuok
Dl-o-borylpbttuUic
CH-n-oclylpbUuUie
Dibcuafuim
CHelbylpbUuUlc
Plooriolbcoe
Plooreoe
NipbUulne
PbeniDlbicoe
Pyrene
W
NS
20
10
10
14
1400
NS
700
10
NS
5600
42
10
10
10
10
d
NS
c
c
c
NS
NS
NS
NS
NS
NS
NS
c
c
d
c
c
NS
NS
ra
NS
NS
41
I00f
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
O1
NS
NS
KB
NS
NS
NS
NS
NS
NS
NS
< 10
< 10
(2)
(0.1)
(0.4)
(0.6)
(0.3)
< 10
< 10
< 10
(1)
< 10
(3)
(0.7)
(0.3)
(0.2)
(J)
< 11
< II
(0
(0.1)
m
U 1 60
U < 11
< II
< II
< II
(O
< II
(5)
<«>
(0-4)
()
(3)
U <
1
V <
1
1 <
1 <.
1 <
I'-
U
J
u <
J
u
j
u <
J
J <
u
J
J <
1 <
j <
J <
J <
10
10
10
10
10
-------
TABLE 2-9
SUMMARY OF CONSTITUENTS DETECTED IN GROUNDWATER
SAMPLES COLLECTED IN 19» AT
SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2
Homestead Air Reset-re Base, Florida
(Page 3 of 3)
Parameter
Mitanioa
Min(>mt
PoUMloa
Sodlim
CYANIDE (o»/L):
TOTAL DISSOLVED SOLIDS (ntf/L):
Florida
Ground-
wilcr
GukUaca
CoocnlralioM
m
NS
3d1
NS
160000k
134
5001
fAC
17-771
Florida
NS
NS
NS
NS
NS
NS
EPA
DrtnkJnj.
Waur
Slmdardi
NS
so"
NS
NS
vf
SCO"
EPA
Maxtmoro
Conlamlnanl
L«T>t Goal
NS
NS
NS
NS
vf
NS
CAM IX). fTTAJ-
Snumah 1X1. MW-4
DaU Sampled 40SOt-l
1/I093
(«IO)
1 "2 1
~tt!o)
10700
< 10
1 «« 1
rrvTA^MWS
407(3-3
2/W93
(3340)
(14X)
10300
< 10
470
DMW1
408M.3
lt\W»
(4330,
< 10
6170
32900
< 10
410
Equipment
Blank
4«804-l
1/1 OT3
< 300
< 10
< 1000
< 300
< 10
3
NOTES:
" The total of volatile organic aromatia (benzene, toluene, ethylbenzeoe and xylenes) must be <50 ug/L to meet FAC 17-770 guidelines.
The total of polynuclear aromatic hydrocarbon] excluding naphthalenei must be <10 ug/L to meet FAC 17-770 guidelines.
The total of naphthalenes and methyl naphthalenes must be <100 ug/L to meet FAC 17-770 guidelines.
Numbers represent EPA's Final MCL (Max Contaminant Levels).
Numben represent EPA's Proposed Primary MCL ot Proposal MCLG, Federal Register, Vol. 55, No. 143, July 1990.
Numbers represent EPA's Primary MCL for Inorganics.
Numben represent EPA's Secondary MCL for Inorganics which are non-enforceable taste, odor or appearance guidelines.
Numbers represent EPA's Final MCL effective July 1992, Federal Register, January 30, 1991 and July 1, 1991.
Florida Primary Drinking Water Standard.
Florida Secondary Drinking Water Standard.
Florida Ground-Water Guidance Concentrations for Minimum Criteria Requirements (Rule 17-3.402, FAC).
No Standard Available.
Result is greater than instrument detection limit but less than practical quantitation limit.
Positive result has been classified as qualitative.
Analyte was n6t detected and has been classified as qualitative.
Result has been classified as undetected.
Analytical Result was generated from * reextraction and reanalysis of the sample.
Concentration exceeded Florida Groundwater Guidance Concentration.
c
d
e
f
8
b
i
k
1
m
NS
J
UJ
U
-------
TABLE 2-10
SUMMARY OF CONSTITUENTS DETECTED IN SURFACE WATER SAMPLES
COLLECTED IN 1993 AT SITE FT-S
FIRE PROTECTION TRAINING AREA NO. 1
HOMESTEAD ADI RESERVE BASE, FLORIDA
Parameter Florida Out
IQFrab
Surficc Water
Quality
Standard
Volatile Organic Compound*
(HS/L)
Bromodichlorcm ethane
2-Butanooe
Mcthylene Chloride
1 , 1 , 1 -Trichloroethane
Base/Neutral aod
Add Extractable Compound*
(MS/L)
bis(2-
Ethylhexyl)pbthalate
Butylbenzylphlhalate
Organocblorlne
Pe*tidde*/PCB* (ug/L)
Metal* (jlg'L)
Cafcium
Magnuium
Potauhim
Sodium
Cyanide Olg/L)
Total Dtraolred SoUdi (mg/L)
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
<5
NS
Federal GAM I.D. FPTA2-SW-0001
Water Savannah LD. 40742-*
Quality Date 2*93
Criterion Sampled
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
5.2
NS
(1)
< 10
< 10
< 10
< 10
< 10
ND
77.700
(2.220)
(3.830)
13.700
< 10
203
FPTA2-SW-0002
40742-5
2/8/93
(1)
< 10
< 10
< 10
(2) U
(0.2) U
ND
77.500
(2.230)
(3,930)
14.000
< 10
203
FPTA2-SW-0003
40742-4
2/8/93
(1)
< 10
< 10
(2)
18 U
(0.2) U
ND
75.800
(2,250)
(3,840)
14.000
< 10
199
FPTA2-SW.9003
40742-3
2/8/93
(1)
< 10
< 10
(2)
(2) U
(0.2) U
ND
71,600
(2,170)
(3.800)
13,900
< 10
188
FPTA2-SW-0004
40742-2
2/8/93
(2)
< 10
(1) U
(3)
(0.4) U
(0.2) U
ND
74,500
(2.250)
(3,870)
14.200
< 10
195
FPTA2-SW-0005
40742-1
2O/93
(2)
(7)
(8)
(4)
(0.9)
(0.3)
ND
75,800
(2.310)
(3.910)
14,400
< 10
199
U
U
U
Note*:
U Classified at undetected.
( ) Value U gretfer than instrument detection limit but leal than practical quantitalioo limit
ND None of the compound* in thi* analyte group were detected.
-------
TRPH was not detected in any of the 1988 groundwater samples. Concentrations of Cg-C20
hydrocarbons were detected in three of the 15 samples taken in 1989 and analyzed for this
constituent, at concentrations of 318, 1,510, and 32,000 Jig/L. TRPH was detected in three of
the 11 groundwater samples collected in 1991. The concentrations of the three samples were
1.0, 6.1, and 21 Jig/L. These concentrations were much lower than the 1989 C8-C20
concentrations and were detected in approximately the same locations (Figure 2-1).
TRPH was not detected in any of the 1988 sediment or surface water samples. The sediment
and surface water samples collected in 1993 were not analyzed for TRPH.
2.6.2.4 Base/Neutral and Acid Extractable Compounds. BNAs (mostly PAHs) were
detected in 15 of the 19 soil samples collected in 1989. The concentration of total PAHs
ranged from about 5 to 1,400 mg/kg (Figure 2-2). BNAs (mostly PAHs) were detected in all
four of the surface soil samples collected in 1991. The concentration of total PAHs ranged
from about 0.6 to 180 mg/kg (Figure 2-2). BNAs (mostly PAHs) were detected in all 11 of
the surface soil samples collected in 1993. The concentrations of total PAHs ranged from
about 0.1 to 2,372 mg/kg (Figure 2-2, Table 2-8). In general, the highest concentrations of
PAHs detected during the investigations were found in and below the fill area, and in an
asphalt area east of Campbell Drive. The source of PAHs in the fill area is unknown but is
likely from asphalt (which contains PAHs) that was placed at the site after the fire training
activities ceased. The PAHs in the other surface soils are likely from the burning activities
during fire training exercises and/or from the asphalt in the fill area.
BNAs were not detected in any of the 1988 groundwater samples collected. However, these
samples were collected along the perimeter of the elevated fill area and could not be used to
characterize groundwater quality beneath the fill. BNAs (mostly PAHs) were detected in
four of the 17 groundwater samples collected in 1989. Total PAH concentrations (excluding
naphthalene) ranged from about 47 to 436 |ig/L. Total naphthalene concentrations ranged
from 17 to 388 ng/L (Figure 2-3). BNAs (mostly PAHs) were detected in five of the
11 groundwater samples collected in 1991. Total PAH concentrations (excluding
naphthalene) ranged from about 7 to 85 |ig/L. Total naphthalene were detected in two
samples at concentrations of 0.45 and 70 u.g/L (Figure 2-3). BNAs (mostly PAHs) were
detected in four of the six groundwater samples collected in 1993. Total PAH concentrations
(excluding naphthalene) ranged from less than 1 to 26.1 u.g/L. Total naphthalene
concentrations ranged from 0.3 to 1.3 u,g/L (Figure 2-3, Table 2-9).
20
-------
N
0 100 200
SCALE IN FEET
Ordnance £
FPTA2-SI
Total PAH
FPTA2-SB6 4-8 Fl. 6-10 Fl.
Total PAHs | 585.14 542
N _ _ ""
FPTA2-SS2 0-3 Fl. 3-6 Fl.
Total PAHs (1,381.91 53.05
FPTA2-SL-0018 1993 |
Total PAHs
12 4 1
1991
80
FPTA2-SL-0019 1993 |
Total PAHs
01 1
**l-/-9
SL9/99
0019
X.
FPTA2-SB5 4-8 Fl.
Total PAHs
214.35
6-10 Fl. |
I H
5
r
FPTA2-SL-0023 1993 |
Total PAHs
1.663 |
FPTA2-SL-0014
Total PAHs
FPTA2-SL-11
Total PAHs
^x /
^ .
/ ^--/. »
014
19931 r
2,372 1
1991
104
SB-6
SS-2
Building
4076
FPTA2-SL-0020 1993
Building
4071
Total PAHs
7.9
0020
FPTA2-SL-0017
Tola! PAHs
1993 |
14.0 1
FPTA2-SB7
Total PAHs
0-4 Fl. 6-10 Ft. |
1 501.49
6.87 |
FPTA2-SS3 0-3 Fl. 3-6 Ft. |
Total PAHs
602.61
415.8 |
X 0015,
SS-3 '
SL-11
0016 A
- SB-Sm \
Elevated Fin/Vegetation Area
FPTA2-SS1
Total PAHs
0-3 Fl. 1
| 136.2 I
SS-1
0013
0021
SL-10,
SS-4
SB-8
FPTA2-SL-0016 1993 {
Total PAHs
1.752 1
FPTA2-SL-0012 1991 |
Total PAHs
0.7
FPTA2-SL-0021 1993 |
Total PAHs
2.2 |
FPTA2-SL-
0013/9013 1993
Tolal PAHs
66.3
1993(o,,,,| j
57 4
FPTA2-SL-0022 1993 | //
Total PAHs 21.6 | ^^ A
//_ Total PAHs 156.3f
LEGEND
1989 Soil/Weathered Rock Sampling Location
1991 Soil/Weathered Rock Sampling Location
A 1993 Soil/Weathered Rock Sampling Location
Total PAHs Polynuclear Aromatic Hydrocarbons, excluding Na
All Results in milligrams per kilogram (mg/kg)
Paved Road
ITT ~T~ Drainage Canal
Reference: GSM, 1994a
',./ "D-' \ /
,t^ I \
/" / -V
^ / FPTA2-SB8 4-8 Ft.
' j _/ Total PAHs 455.58
J FPTA2-SL-0015 1993 KX^X^^
Total PAHs | 157.B | |^\ ^
II \\
" \\
M \
II XX
phlhalenes .
To
Boundary
Canal
/^ Total PAHs | 18 j
6-10 Fl. j FPTA2-SS4 0-3 Fl. 3-6 Ft. |
35-15 | Total PAHs 964.2 1084 |
\
^^ Drainage Swale
^k
U.S. ARMY CORPS OF ENGINEERS
HOMESTEAD ARB
POLYNUCLEAR AROMATIC HYDROCARBONS DETECTED
IN SOIL/WEATHERED ROCK SAMPLES COLLECTED
DURING THE 1989, 1991 AND 1993 FIELD INVESTIGATIONS
SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2
FIGURE 2-2
-------
Total PAHS
Total Naphthalenes
(
Building
Building
4076
FPTA2-MW5 1989 1991 1993
Total PAHs
Tolal Naphthalenes
317
170
84.75
0.45
26.1
0.4
MW2
FPTA2-MW3 1989 1991 1993
Total PAHs
Total Naphthalenes
ND
ND
6.68
0
NS
NS
\.
FPTA2-MW1
Tolal PAHs
Tolal Naphthalenes
/
1989 1993
6.22
127
0.03
1.3
MW1 / TW-22
\ *
1993(1 up) 1
032 1
/ Concrete
V Fad \ x
', 1993
Total PAHs
Tolal Naphthalenes
46.8
17
29.59
0
14.08
0
8.4
0.3
Drainage Ditch
LEGEND
Tolal PAHs
Groundwater Sampling Location
Polynuclear Aromatic Hydrocarbons,
excluding Naphthalenes
ND Not Detected Above Instrument Detection Limits
NS Not Sampled
All Results in Micrograms per Liter (pg/L)
' Paved Road
Drainage Canal
Reference: G&M. 1994a
100
200
SCALE IN FEET
To
Boundary
Canal
U.S. ARMY CORPS OF ENGINEERS
HOMESTEAD ARB
ORGANIC COMPOUNDS DETECTED IN
GROUNDWATER SAMPLES COLLECTED DURING
THE 1989,1991, AND 1993 FIELD INVESTIGATIONS
SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2
FIGURE 2-3
-------
The total PAH concentrations (including naphthalene) detected in groundwater samples
FPTA2-MW1/FPTA2-SL-9001, FPTA2-MW2, FPTA2-MW4, and FPTA2-MW5 in 1993
were 100/57, 53, 3, and 3 times lower, respectively, than concentrations detected in 1991.
Similar results were found in the Phase I investigation where concentrations of total PAHs
detected in samples FPTA2-MW2, FPTA2-MW4, and FPTA2-MW5 analyzed in 1991 were
from 2 to 7 times lower than total PAH concentrations detected in 1989. The decrease in
total PAH concentrations in monitoring wells FPTA2-MW2, FPTA2-MW4, and
FPTA2-MW5 between 1989, 1991, and 1993, and FPTA2-MW1 between 1991 and 1993
suggests that the PAHs are attenuating naturally, probably from aerobic biotransformation
(G&M, 1993a). However, total PAHs (excluding naphthalene) detected in one 1993
groundwater sample (FPTA2-MW5) still exceeded the state MCL of 10 p.g/L with a
concentration of 26.1 jig/L. None of the 1993 groundwater samples collected exceeded the
state MCL for total naphthalene of 100 jig/L.
BNAs were not detected in the 1988 surface water samples collected. Two BNAs were
detected but classified as undetected in the 1993 surface water samples collected
(Table 2-10).
BNAs were not detected in the 1988 sediment samples collected. BNAs (mostly PAHs) were
detected in all five of the 1993 sediment samples collected (Table 2-11). Total PAH
concentrations ranged from about 0.05 to about 8.8 mg/kg. Several of the BNAs detected
exceeded National Oceanic and Atmospheric Administration (NOAA) Effects Range-Low
(ER-L) guidelines.
2.6.2.5 Inorganics. Lead was detected in 10 of the 12 surface soil samples collected in 1989.
The lead concentrations ranged from 0.7 to 78 mg/kg. Lead was detected in all four of the
surface soil samples collected in 1991 at concentrations of 21 to 1,100 mg/kg. Originally, the
1991 samples were collected as background samples. However, a review of aerial
photographs suggests that these samples were collected in the vicinity of a former fire
training pit and are not appropriate background samples. Lead was detected in all 11 of the
surface soil samples collected in 1993. The lead concentrations detected in 1993 ranged
from 7.4 to 110 mg/kg (Table 2-8). Detected lead concentrations are summarized in
Figure 2-4.
Because the background soil sample collected at Site FT-5/OU-1 may be inappropriate, lead
concentrations detected in surface soil/weathered rock samples collected at Site FT-5 were
compared to average Homestead ARB concentrations (Table 2-6). Concentrations of lead
21
-------
Ordnance Storage Area -V.
0 100
SCALE IN FEET
Building |
4076
FPTA2-SL-0014 1993
0016
SB-5~|i \
Elevated FilWegelalion Area
Drainage Swale
1989 Soil/Weathered Rock Sampling Location
1991 Soil/Weathered Rock Sampling Location
1993 Soil/Weathered Rock Sampling Location
U.S. ARMY CORPS OF ENGINEERS
HOMESTEAD ARB
LEAD CONCENTRATIONS DETECTED IN
SURFACE SOIL/WEATHERED ROCK SAMPLES COLLECTED
DURING THE 1989,1991 AND 1993 FIELD INVESTIGATIONS
SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2
All Results in milligrams per kilogram (mg/kg)
Paved Road
To
Boundary
Canal
Drainage Canal
Reference: G&M. 1994a
-------
detected in 25 of the 27 surface soil/weathered rock samples collected in 1989, 1991. and
1993 were above the Homestead ARE lead background range for surface (0 to 2 ft bis)
soil/weathered rock.
Additional target analyte list (TAL) metals and general minerals detected in the four shallow
soil samples collected in 1991, and 11 surface soil samples collected in 1993 included
aluminum, calcium, barium, cadmium, chromium, copper, iron, magnesium, manganese,
nickel, potassium, sodium, vanadium, zinc, mercury, and arsenic. The 1993 results are
presented in Table 2-8. These metals are typically present in carbonate rocks and soils.
According to average carbonate composition data presented by Hem (1989), calcium,
magnesium, aluminum, iron, manganese, potassium, and sodium are the most common
constituents of carbonates. Additionally, barium, chromium, copper, nickel, vanadium, zinc,
mercury, and arsenic occur as trace concentrations. Average concentrations of two common
carbonate constituents (calcium and sodium) and three trace carbonate constituents (barium,
chromium, and zinc) detected in Homestead ARB background surface (0 to 2 feet bgs)
soil/weathered rock samples were above the average carbonate composition concentrations
(Hem, 1989).
Soil samples collected in 1993 were analyzed for cyanide. Cyanide was not detected in any
of the 11 soil samples collected.
Lead was detected in four of the six groundwater samples collected in 1988. The
concentrations ranged from 1.2 to 2.7 fig/L. Lead was detected in four of the 17 groundwater
samples collected in 1989. The concentrations ranged from 7.5 to 311 |lg/L. Two of the
samples were above the federal action level of 15 u.g/L and one of the samples was above the
state MCL of 50 u,g/L. Lead was detected in six of the 11 groundwater wells sampled in
1991. The concentrations ranged from 7.5 to 67 ^ig/L. Three of the samples were above the
federal MCL of 15 (ig/L and two samples were above the state MCL of 50 p.g/L. Lead was
not detected in any of the six groundwater samples collected and analyzed for lead in 1993.
This may be attributed to sampling techniques.
Additional TAL metals and general minerals detected in groundwater samples collected in
1993 include barium, calcium, iron, magnesium, manganese, potassium, sodium, and arsenic
(Table 2-9). No groundwater quality standards or guidelines exist for calcium, magnesium,
and potassium. Calcium (89,600 to 149,000 \igfL), magnesium (1,670 to 4,550 (ig/L), and
potassium (1,350 to 6,170 Hg/L) are within or slightly above the range of dissolved calcium,
magnesium, and potassium reported for the Biscayne aquifer (Table 2-7). Arsenic was
22
-------
detected in one groundwater sample at 12.1 Jig/L which is well below the state MCL of
50 |ig/L. Barium was detected in four samples at concentrations ranging from 12.5 to
50.8 |ig/L, which are well below the state MCL of 1,000 fig/L. Sodium was detected in all
groundwater samples at concentrations ranging from 6,340 to 32,900 [igfL, which are well
below the state MCL of 160,000 fig/L.
High concentrations of TAL metals including aluminum, lead, and manganese detected in the
1991 groundwater samples have been attributed to the presence of suspended sediments in
the groundwater samples. Redevelopment of these wells, which removed suspended
sediment, prior to collecting groundwater samples in 1993 provided more accurate
measurements of dissolved TAL metals. Aluminum concentrations detected in the 1991
samples exceeded the federal Secondary MCL (SMCL) (50 to 200 |ig/L) for drinking water.
The 1993 samples were all below the detection limit of 200 u,g/L. Lead concentrations
detected in samples FPTA2-MW1 and FPTA2-MW4, which exceeded the federal MCL of
15 ng/L in 1991, were below the detection limit of 3 p.g/L in 1993. Manganese
concentrations detected in samples FPTA2-MW2 and HS-11, which exceeded the federal
SMCL for drinking water and state Secondary Drinking Water Standards in 1991, were
below the detection limit of 10 u,g/L in 1993.
Groundwater samples collected in 1993 were analyzed for cyanide. Cyanide was not
detected in any of the six samples collected. TDS were detected in 1993 groundwater
samples at concentrations ranging from 200 to 510 mg/L. Only one sample contained TDS
concentrations above the SMCL of 500 mg/L (Table 2-7).
Lead was detected in all five of the 1993 sediment samples at concentrations ranging from
4.4 to 39.5 mg/kg (Table 2-11). Lead was detected in all five of the 1988 surface water
samples collected. The concentrations ranged from 2.6 to 7.5 u,g/L. Lead was not detected
in any of the 1993 surface water samples.
Additional TAL metals and general minerals detected in 1993 sediment samples include
aluminum, calcium, chromium, iron, magnesium, manganese, sodium, vanadium, zinc, and
arsenic. At several sampling locations, concentrations of metals detected in the drainage
ditch were greater than background sediment (FPTA2-SD-0001) concentrations (Table 2-11).
Table 2-12 presents the background sediment (FPTA2-SD-0001) concentrations for all
detected metals, the range of concentrations detected in the drainage ditch, and the number of
samples above background for each constituent. Each metal (except sodium) was detected at
concentrations above the two background samples in at least one sediment sample.
23
-------
TABLE Ml
SUMMARY OF CONSTITUENTS DETECTED IN SEDIMENT SAMPLES
COLLECTED IN 1993 AT
SITE FT-5. FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR FORCE BASE, FLORIDA
(P«gelofJ)
""
BwMmtnl **t feU
Eilrwubfc
AflUraam
B*ixo(i)p]mM
B* ti*X klflvonMbcM
^ g T*K 1, H it)P*TT W X
Cutaoto
QOr
4.4--DDD
4X-DDB
Atenira
Am*
Cildu
bw
NOAA
KS-L
M
230
400
N
N
N
N
400
60
600
N
230
350
2
2
N
33
N
to
N
NOAA
HUM
V»!M'
9«0
1.60
0
2 JO
0
N
N
N
N
240
0
260
3.60
»
N
1.40
0
20
15
N
15
N
145
N
Uurlm
SQC
NS
UI7.000
1.063.000
NS
NS
NS
NS
NS
14*3.000
NS
1.3 11, 000
NS
NS
NS
NS
NS
NS
NS
hurlm
SOC
1 l.»*
oc
NS
25.023
20.197
NS
NS
NS
NS
NS
NS
33.777
NS
24,909
NS
NS
NS
NS
NS
NS
NS
GAM IJX JTT/U-SD-
Sxuuk LD. 0001
D.US.mpW 4074>lt
*SoB* 1/4/M
NO
< 150
< 150
< HO
< 1)0
< 150
< 150
< 150
< 150
< 150
< 150
< 150
< 1)0
< 1.)
< 1.5
U20
< ).2
309.000
1.7
IJZOO
ITTA1-SD. rPTAJ^D-
0001 M03
40741-11 40742-17
van i/vn
57 70
NO NO
< 310 (65)
(60) TO
(69) IJ3
(120) 950
(36) 110
(45) 100
< 510 (61)
(91) 790
< 5»o < TTJ
(160) IJOO
(61) 710
(47) (210)
(120) 1.500 1
< 54 J.4
< 5.1 1.9
1 2.150 I 1)3 1
U 11.7 ) 4.2 I
J
307.000 313.000
17 J 1.5
2.360 101
FPTAJ-SD-
FPTA2-SD. 0004
K»3 40741-14
40741-K 2/*3
1/Vti W
it
NO NO
(43) < 720
(«30) (130)
<460) (200)
610 (2*0)
(300) (150)
510 (200)
(74) < 720
315" J (210)
(140) 1 (71)
no (290)
(360) (170)
(190) (65)
»30 1 (3)0)
(3.1) < 7.2
(3.6) 12
1.120 ) 1.930
3.9 J 6J
219.000 2)4.000
1.7 12.6
950 2.120
FPTAJ-SD-
0005
4070
(47)
(52)
< 4&0
J (63)
"1 < 4*0
(110)
(10)
(110)
< 4.1
< 4.1
J 959
1 < 2.9
263.000
4.7
662
J
1
1
-------
TABLE Ml
SUMMARY OF CONSTITUENTS DETECTED IN SEDIMENT SAMPLES
COLLECTED IN 1993 AT
SITE FT-5, FERE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR FORCE BASE, FLORIDA
(P«gt2of2)
(J(XAA NOA Uurlm
NnmiUr OH, . A SQC
Vtht M ' £$
v* OQ
L.14 35 110 NJ
Mi(i»4» N N K»
MUIUM N N W
Jii»n 1 1 M
Jodlw M N M
Vmutun N N N$
ZJK IM 770 MS
C7«>ld« (tnfAt *) KS Nl K5
T»UIOrtuk CarbM (BaAiO) » W W
Art* VW.ll. MMt (na/lf 4V) f« fB M
AVS KitncUbb MiUK
lixl (7411), a|/kj tfw NJ NJ W
Z!M (4010), Bf/kf *w » « M
Notes:
8 The sediment cnulitv criteria (SOO cannot be direct!!
Uurlm
»QC
OC
US
XI
N3
W
M
NJ
N5
M
W
W
m
GAM IJX FPTAl^D-
J^THkAh LIX 0001
Dttl SAfnplt4 40741-lt
* Soldi 1/4/93
19
(669)
111
< 5.1 <
(673)
(3.1)
< 0.45 . <
< 14.000
< 14 <
< 9.1 U
1
11.4 J
/ comoared with the Site FT-5 drainaee ditch data becau
FTTAl^D- FTTAJ-SD-
0001 000)
40741.11 40743-IT
1/4/93 1/4/9)
57 1%
11.5 |
(IM)
10J
)J <
(5SH
(7.1)
13.3
0.44 <
11,000
II
1.1 I
9.7 I
se the SOC ire Dresente<
35.4 1
(711)
IM
1.9 <
(401)
(4.0)
49.9
OJ« <
15.000
16
17.) 1
25.) 1
t a* normalized to orian
00)
1/4^3
49
31.3 |
(»0)
13.1
19 <
(4TT)
(4.4)
39.0
0.34 <
13.000
U
10.1 )
117 J
ic carbon (i.e., presente<
0004
40741-14
1/tft)
44
J9.5
(T76)
19.4
4.4
(340)
(9-9)
14.4
a 55
15.000
40
13.0
11.7
on a per or
0001
4*743-15
1/4/t)
49
1 M
(413)
9.9
< 1.9
(401)
(4.4)
4.9
< 0.)4
11.000
13
I < 4.9
1 5.1
tanic carbon weicht bas
u
J
I
ls).T
(Jij/Vg OC) by the avenge OC content of 1.9% (.019 kg of COkg of sediment).
Organic Caibon
The criteria U that a sediment U not actively toxic when the molar sum of simultaneously extracted cadmium, copper, mercury, nickel, lead, and line U leu than the molar acid volatile sulfide concentration (DiTolo a al., 1992).
National Oceanic and Atmospheric Administration (NOAA) Technical Memorandum NOS OMA 52. Effects Range - Low value* are concentrations equivalent to the lower 10 percentile of available data screened by NOAA and
indicate the low end of the range of concentrations in specific sediments at which adverse biological effects were observed or predicted In sensitive specie* and/or sensitive life suges.
Effects Range Median value* are concentrations equivalent to the midpoint of the range of available data screened by NOAA.
1 Positive result has been classified a* qualitative.
U Classified as undetected
UI Analyte was Dot detected.
NS No Standard
N No value available
() Value is greater than instrument detection limit but leu than practical quantitation limit
Value exceeds NOAA ER-L To-Be-Considered guidelines
)ig/kg micTOgTun* pet kilogram dry weight
tug/leg milligrams pet kilogram dry weight
NO None of the compounds In this analyle group were detected.
-------
TABLE 2-12
COMPARISON OF METALS DETECTED IN SEDIMENT SAMPLES COLLECTED
AT SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2, WITH BACKGROUND CONCENTRATIONS
HOMESTEAD AIR RESERVE BASE, FLORIDA
Analyte
Aluminum
Calcium
Chromium
Iron
Magnesium
Manganese
Sodium
Vanadium
Zinc
Lead
Arsenic
Average
Carbonate
Composition
8,970
272.000
7.1
8,190
45,300
842
393
13
16
16
1.8
Background
Boundary Canal b/
Sediment
«/ BC-SD-0010
2,700
310,000
11
1,700
1,000
<29
290
5.7
27
11
2
Background
Site FT-5
Sediment
FPTA2-SD-0001
1.320
309,000
8.7
1.200
669
12.8
672
5.8
25.6
19
<5.2
Site FT-5
Sediment
Concentration
Range (4) c/
853 - 2,850
254,000-370,000
4.7-17.3
662 - 2.360
613-880
9.9 - 29.6
340 - 553
4.0 - 7.8
6.9 - 49.9
4.4-39.5
<2.9- 11.7
a/ Hem, J.D., 1989 Average carbonate composition of precipitates in carbonates.
b/ Boundary Canal sediment sample located approximately 500 feet east of Mystic Lake on the north side of Homestead AFB.
c/ Number of samples considered.
I:\pio|\l(704\II 5\IABL4-I6.XLS
-------
The following metals and general minerals were detected in surface water samples collected
from the Site FT-5/OU-1 drainage ditch: calcium (71,600-77,700 M-g/D. magnesium
(2,170-2,250 Hg/L), potassium (3,800-3,930 jig/L), and sodium (13,700)-( 14,400 ug/L)
(Table 2-10). These constituents are present in the groundwater of the Biscayne aquifer, the
major source of water in the Site FT-5/OU-1 drainage ditch (Table 2-7). Concentrations of
calcium, magnesium, potassium, and sodium detected in the Site FT-5 drainage ditch were
within the ranges detected in the Biscayne aquifer (Table 2-10).
Cyanide was not detected in any of the 1993 sediment or surface water samples collected.
2.6.2.6 Pesticides/PCBs. The 11 soil samples collected in 1993 were analyzed for target
compound list (TCL) pesticides/PCBs. Three pesticides, heptachlor epoxide, 4,4'-DDE, and
4,4'-DDD were detected in the soil/weathered rock samples (Table 2-3). Heptachlor epoxide
was detected in soil/weathered rock samples FPTA2-SL-0014 and FPTA2-SL-0016 at
concentrations of 200 and 260 |ig/kg, respectively. 4,4'-DDE and 4-4'-DDD were detected in
FPTA2-SL-0013 at concentrations of 24 and 270 mg/kg, respectively, and in
FPTA2-SL-9013 (duplicate of FPTA2-SL-0013) at concentrations of 34 and 340 u.g/kg,
respectively. The concentration of 4,4'-DDE detected in FPTA2-SL-9013 was between the
method detection limit and practical quantitation limit and the concentrations of heptachlor
epoxide detected were qualified because of errors in the associated quality control measures.
These pesticides were not detected in average Homestead ARB background concentrations
for surface (0 to 2 feet bgs) soil/weathered rock.
Organochlorine pesticides were not detected in groundwater samples collected in 1993. Two
organochlorine pesticides were detected in the 1993 sediment samples collected. 4,4'-DDD
was detected in two samples at concentrations of 5.4 and 3.1 Hg/kg and 4,4'-DDE was
detected in three samples at concentrations ranging from 3.6 to 12 p.g/kg (Table 2-11).
Concentrations of 4,4'-DDD and 4,4'-DDE detected in sediment samples exceeded NOAA
ER-L guidelines of 2 Jig/kg. Organochlorine pesticides/PCBs were not detected in the
surface water samples collected in 1993.
2.6.2.7 Total Organic Carbon. The varying toxicity of nonionic organic chemicals in
different sediments is related to the TOC content in sediments. This is due to TOC in
sediment controlling the extent of adsorption. TOC was analyzed in all 1993 drainage ditch
sediment samples. Concentrations detected in all five sediment samples ranged from
12,000 to 26,000 mg/kg (Table 2-11), with an average TOC of 1.9 percent. The average
24
-------
TOC of 1.9 percent was used to calculate the interim Sediment Quality Criteria (SQC). The
SQC cannot be directly compared with the drainage ditch data because the SQC are
presented as normalized to organic carbon (i.e., presented on a per organic-carbon-weight
basis). To allow a direct comparison between the drainage ditch data and the SQC, the SQC
for the average carbon content in drainage ditch sediments (1.9 percent) was calculated, and
is presented in Table 2-11.
2.6.3 Summary
The most prevalent constituents detected in the soil/bedrock and groundwater at Site FT-5
are semivolatile organic compounds (SVOCs) (i.e., BNAs). The SVOCs detected in the
soil/bedrock and groundwater are primarily 2- to 5-ring PAHs. VOCs were detected at low
levels in some of the surface soil samples collected in 1989 and all of the 1991 and 1993
samples. Most of the VOCs detected are suspected as laboratory contaminants. VOCs,
primarily benzene and toluene, were detected in four of the 17 groundwater samples
collected in 1989, in two of the 11 groundwater samples collected in 1991, and in one of the
six groundwater samples (and its associated duplicate) collected in 1993. VOC
concentrations in groundwater decreased significantly since 1989 and 1991 suggesting
natural attenuation, possibly from biodegradation.
Metals (except for lead) were detected in the soils and groundwater at Site FT-5 at
concentrations within typical background levels. Lead concentrations detected in surface soil
samples were generally below 100 mg/kg. Only three samples had lead concentrations
greater than 100 mg/kg. Lead was detected in groundwater samples collected in 1989 and
1991 at concentrations greater than the state MCL. Lead was not detected in the groundwater
samples collected in 1993. Low concentrations of VOCs, BNAs, and metals were detected in
the sediment and surface water samples.
2.7 SUMMARY OF SITE RISKS
In order to evaluate whether existing or future exposure to contaminated media at Site
FT-5/OU-1 could pose a risk to human health and the environment; the USAF completed a
Baseline Risk Assessment (BRA) in April 1994, with USEPA oversight of the process. The
USAF evaluated potential site risk in the absence of any further remediation. This evaluation
then served as a baseline for determining whether cleanup of each site media was necessary.
In the BRA, the USAF evaluated site risk for several environmental media. This ROD
addresses the risks attributable to chemicals in the groundwater and soil at Site FT-5/OU-1.
25
-------
The BRA included the following major components: selection of chemicals of potential
concern (COPC), exposure assessment, toxicity assessment, risk characterization,
development of remedial goal options, ecological risk and uncertainties.
2.8 SELECTION OF CHEMICALS OF POTENTIAL CONCERN
Chemicals are included in the BRA as COPCs if the results of an initial screening indicate
the chemical might pose a current or future risk above levels deemed protective of human
health and the environment by the USEPA. COPCs at Site FT-5/OU-1 were based on the
twice background criteria for organic chemicals, elimination of lab contaminants and
detection frequency for organic chemicals and essential nutrient elimination.
COPCs for soil, groundwater, surface water, and sediment in Table 2-13.
2.9 EXPOSURE ASSESSMENT
In the exposure assessment, USAF considered ways in which people could come into contact
with contaminated media under both current and future conditions. A critical step in
assessing the potential risk to public health is to identify the pathways through which
exposure to chemicals could occur. A typical transport pathway consists of four necessary
elements: 1) a source and mechanism of chemical release; 2) an environmental transport
medium; 3) a point of potential contact with the contaminated medium, and 4) exposure route
(inhalation of vapors, ingestion of groundwater, etc.). All four of these elements must be
present for a pathway to be complete.
2.9.1 Exposure Point Concentration
The exposure point concentration for each contaminant was derived using the 95 percent
upper confidence limit (UCL95) on the arithmetic mean as defined by the following formula:
where: y = arithmetic mean of the log-transformed data
S = standard deviation of the log-transformed data
H = statistical parameter
26
-------
TABLE 2-13
CHEMICALS OF POTENTIAL CONCERN AT
FT-5, FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR RESERVE BASE, FLORIDA
(Page 1 of 2)
Constituent
Groundwater
Surface
Soil
Total
Soil
Surface
Water
Sediment
VOCs
Acetonea
Benzene
Bromodichloromethan
e
2-Butanonea
Ethylbenzene
Methylene chloride2
Toluene
1,1,1-Trichloroethane
Xylenes (total)
BNAs
Acenaphthene
Acenaphthylene
Anthracene
Benzo(a)anthracene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Benzo(a)pyrene
Benzo(g,h,i)perylene
Butylbenzylphthalate
Carbazole
Chrysene
Dibenzo(a,h)anthracen
e
Dibenzofuran
Diethylphthalate
Fluoranthene
Fluorene
n-Hexane^
Indeno(l,2,3-
c,d)pyrene
2-Methylnaphthalene
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
-------
TABLE 2-13
CHEMICALS OF POTENTIAL CONCERN AT
FT-5, FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR RESERVE BASE, FLORIDA
(Page 2 of 2)
Constituent
Naphthalene
Pentachlorophenol
Phenanthrene
Pyrene
Pesticides
4,4'-DDD
4,4'-DDE
Heptachlor epoxide
Metals
Aluminum
Arsenic
Cadmium
Chromium
Cobalt
Copper
Iron
Lead
Manganese
Nickel
Vanadium
Zinc
Petroleum
Hydrocarbons
Groundwater
X
X
X
X
X
X
X
X
X
Surface
Soil
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Total
Soil
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Surface Sediment
Water
X
X
X
X
X X
X
a Strongly suspected laboratory contaminant
b n-Hexane is used as a surrogate for petroleum hydrocarbons.
Adapted from: Geraghty & Miller, 1994a,b
-------
Often, with limited data sets, the UCLgs is higher than the maximum detected concentration.
If so, the maximum concentration detected was used as the exposure point concentration
rather than the
2.9.2 Land Use
Hypothetical future use of the site for residential purposes is unlikely. However, for the
purposes of the BRA, the hypothetical future risks were evaluated for the possibility of future
residential development of the site and installation of a potential potable well.
2.9.3 Exposure Scenarios
Potential current risks at the site were evaluated based on a base worker, accessing the site
for cutting the grass, who could ingest soil, have skin contact with soil, or inhale dust from
soil. Future populations at risk consisted of hypothetical adults and children. Exposure to
contaminated groundwater and soil was evaluated for hypothetical adult and children
residents. Risks were evaluated based on conservative use of Reasonable Maximum
Exposure (RME) assumptions.
The exposure assumptions for each pathway are provided in Tables 2-14 through 2-16.
Based on the exposure point concentrations derived from site data for the chemicals shown in
Table 2-13 and using the exposure assumptions identified in Tables 2-14 through 2-16;
USEPA estimated the chronic daily intake (GDI) associated with each exposure pathway and
population combination. The formula used to calculate the GDI for each pathway are also
provided in Tables 2-14 through 2-16.
2.9.4 Toxicity Assessment
The toxicity assessment evaluated possible harmful effects of exposure to each COPC. A
number of chemicals found at the site, including polycyclic aromatic hydrocarbons (PAHs),
arsenic, benzene, cadmium, chromium, and lead have the potential to cause cancer
(carcinogenic). Cancer slope factors (CSFs) have been developed by EPA's Carcinogenic
Assessment Group for estimating lifetime cancer risks associated with exposure to
potentially carcinogenic compounds. These CSFs, which are expressed in units of (mg/kg-
day)'1 are multiplied by the estimated GDI of a potential carcinogen to provide an upper-
bound estimate of the excess lifetime cancer risk associated with exposure at the intake level.
The term "upper bound" reflects the conservative estimate of the risks calculated for the
27
-------
TABLE 2-14
EQUATIONS AND SAMPLE CALCULATIONS FOR HYPOTHETICAL FUTURE
POTABLE GROUNDWATER EXPOSURE,
SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR RESERVE BASE, FLORIDA
(Page 1 of 2)
Equation Definitions
GWExD. = EPC,- x IR x EF x ED
BWx AP
GWExDd - EPC,- x SSA x PC x ET x EF x ED
BW x AP x UCF
GWExD, - EPC,- x VF. x BR x EF x ED
BWx AP
HI - GWExD. + GWExD.
RfD. RfD.
ELCR - [( GWExD. x CSF. ) + ( GWExD, x CSF.)] x TEF
where:
AP Averaging period (equal to ED x 365 days/year for non-cancer effects; 25.550 days [365
days/year for 70 years] for carcinogenic effects) (USEPA, 1989a).
BR Breathing rate (15 m'/day) (USEPA, 1991 a).
BW Body weight (70 kg for an adult; 15 kg for a child (aged 0 to 6]) (USEPA, 1991 a).
CSF Cancer slope factor for oral (CSF.) or dermal (CSF.) intake (kg-day/mg).
ELCR Excess lifetime cancer risk.
EF Exposure frequency (350 days/year) (USEPA, 1991 a).
ET Exposure time while bathing/showering (hours) (15 minutes - 0.25 hour) (Foster and
Chrostowski, 1987).
ED Exposure duration (30 years for an adult resident; 6 years for a child resident (aged 0 to 6]).
EPC,. Exposure point concentration in groundwater (mg/U (Table 3.1)
GWExD Potable groundwater exposure dose for oral (GWExD.), dermal (GWExDd), or inhalation
(GWE,D,) intake (mg/kg/day).
HI Hazard index.
IR Ingestion rate of drinking water (2 liters/day for an adult; 1 liter/day for a child (aged 0 to
6]) (USEPA, 1991 a; 1989O.
PC Permeability constant (cm/hour) (Table 3.11).
RfD Reference dose for oral (RfD.) or dermal (RfD.) intake (mg/kg/day).
SSA Exposed skin surface area while bathing/showering (18.150 cm2 for an adult; 5.150 cm2 for
a child (aged 0 to 61) (USEPA, 1989d).
TEF Toxicrty equivalency factor for carcinogenic poh/nuclear aromatic hydrocarbons (PAHs)
(Table 3.10); not applicable for other carcinogens.
UCF Unit conversion factor (1,000 cm'/U.
VFW Volatilization factor for volatile organic compounds (VOCs) from household tap water (0.5
Urn3) (USEPA, 1991d).
-------
TABLE 2-14
EQUATIONS AND SAMPLE CALCULATIONS FOR HYPOTHETICAL FUTURE
POTABLE GROUNDWATER EXPOSURE,
SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR RESERVE BASE, FLORIDA
(Page 2 of 2)
Example Calculation: Cancer Effects of Benzo(k)fluoranthene (Adult Resident)
GWExD. = (0.0027 mo/L) (2 L/dav) (350 days/year) (30 years)
(70 k0) (25.550 days)
3.17E-05 mg/kg/day
GWExD,
ELCR
(0.0027 mo/L) (18.150 cm2) (4.1 cm/hour) (0.25 hour) (350 davs/vear) (30 years)
(70 kg) (25,550 days) (1,000 cm'/U
2.95E-04 mg/kg/day
[(3.17E-5 mg/kg/day)(7.3 kg-day/mg)] x 0.1
2.3E-05
CSF, is not available for benzo(k)fluoranthene; therefore, dermal exposure is not included in the ELCR
calculation.
Non-Cancer Effects of Toluene (Child Resident)
GWExD. - (0.0077 mo/L) (1 L/dav) (350 davs/vear) (6 years)
(15kg) (2,190 days)
GWExDd
GWExD,
HI
4.92E-04 mg/kg/day
(0.0077 mo/L) (5.150 cm3) M.O cm/hour) (0.25 hour) (350 davs/vear) (6 years)
(15 kg) (2,190 days) (1,000 cnV/U
6.33E-O4 mg/kg/day
(O.OO77 mo/L) (0.5 UmJ) (15 mj/dav> t350 davs/vear) (6 years)
(15kg) (2.190 days)
3.69E-03 mg/kg/day
4.92E-04 mo/ko/dav
2E-01 mg/kg/day
4.3E-02
6.33E-O4 ma/ko/dav
2E-01 mg/kg/day
3.69E-03 ma/ka/dav
1E-01 mg/kg/day
TK7O402VDM. 1OJ4U»-*»r-*4
-------
TABLE 2-15
EQUATIONS AND SAMPLE CALCULATIONS FOR SOIL EXPOSURE
SITE FT-S, FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR RESERVE BASE, FLORIDA
(Page 1 of 4)
Equation Definitions:
SExD.
EPC. x IR x EF x ED x UC,
BW x AP
mg/kg/day
SExD,
EPC. x SSA x SAR x ABS x EF x ED x UC,
BW x AP
[ mg/kg/day )
SExD,
EPC, x BR x (1 /VF * 1 /PEF) x ET x EF x ED
BW x AP
mg/kg/day ]
VF - Q7C x (3.1416 x a x T)"' x uc
2 x Dei x Pa x Kas z
I m3/kg ]
PEF « Q/C x
UC,
0.036 x {1 - G) x iUm/Ut)' x F
I m3/Jcg
Q/C
(exp{[ (0.1004 x In(AJ) - 5.3466] * (2.92 x sY) })
I (g/m2/sec)/(kg/m3) 1
sY - 0.02685 x [o.25 * lln(A) "
26.3608
( unitless )
Dei x Pa
Pa * IPS x (1 -Pa)/Kas]
I cma/sec ]
Dei - Di x (Pa"3/?!1)
ELCR - [ (SExD. x CSF.) * (SExD« x CSF.) « (SExD, x CSF,) J x TEF
I cm7/sec 1
[ unitless 1
HI
SExD. ^ SExD, ^ SExD.
RfD0 * RfD. RID,
( unitless )
where:
A
ABS
AP
Contiguous area of contamination (m2); 11 acres (44,500 m2).
Dermal absorption efficiency, constituent-specific (Table 3.11).
Averaging period (25,550 days (70 years x 365 days/year) for cancer effects; ED x 365 days/year for non-
cancer effects) (USEPA, 1989a).
inrrri nofmt »»ITI
-------
TABLE 2-15
EQUATIONS AND SAMPLE CALCULATIONS FOR SOIL EXPOSURE
SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR RESERVE BASE, FLORIDA
(Page 2 of 4)
BR Breathing rate 10.83 m'/hour [20 m3/dayj for residents; 2.5 m'/hour 120 ms/8-hour dayl for the base worker)
(USEPA, 199 la).
BW Body weight (70 kg for an adult; 15 kg for a child (aged 0 to 6] [USEPA, 1991 all.
CSF Cancer slope factor for oral (CSF0), dermal (CSFJ, or inhalation (CSF,) intake (kg-day/mg) (Table 3.10).
Dei Effective diffusivity (cmj/sec).
Di Diffusivity in air (cm2/sec) (Table 3.7).
ED Exposure duration (years) (25 years for a base worker (USEPA, 199la); 30 years for an adult resident (USEPA,
1989al; 6 years for a child resident [aged 0 to 61).
EF Exposure frequency (days/year) (350 days/year for residents (USEPA, 1991 a); 12 days/year for a base worker).
ELCR Excess lifetime cancer risk (unrtless).
EPC, Constituent exposure point concentration in soil (mg/kg) (Table 3.2 for base worker; Table 3.3 for residents).
ET Exposure time (4 hours/day for a base worker; 24 hours/day for residents).
F Function of Ut/Um (0.0126)(unitJess); F - 0.18 x ( 8x* + 12x ] x exp(-x2), where x = 0.886 (Ut/Um).
Foe Fraction organic carbon in soil (0.02).
G Fraction of vegetative cover (unitless); conservatively assumed as zero.
H Henry's Law Constant (atm-m'/mol) (Table 3.7).
HI Hazard index (unitiess).
IR Incidental ingestion rate for soil (50 mg/day for a base worker; 100 mg/day for an adult resident; 200 mg/day
for a child resident (aged 0 to 61) (USEPA. 1991 a).
Kas Soil-air partition coefficient (g soil/cm* air); calculated as (41 mol/atm/m*) x H / (Koc x Foe).
Koc Organic carbon partition coefficient (cmj/g or mUg) (Table 3.7).
Pa Air-filled soil porosity (0.06) (unitiess).
|PEF Paniculate emission factor (site-specific) (1.83 x 10'° mj/kg).
ft Total soil porosity (0.43) (unitiess).
ps True soil or particle density (2.65 g/cm').
RfD Reference dose for oral (RfD,}, dermal (RfD.), or inhalation (RfD,) intake (mg/kg/day) (Table 3.9).
SAR Soil adherence rate (1 mg/cm2/day) (USEPA, 1992b).
SExD Soil exposure dose from oral (SExD.). dermal (SExD,), or inhalation (SExD,) exposure (mg/kg/day).
SSA Exposed skin surface area (3,160cm2for base worker (USEPA, 1992bl; 4,650cm2 for an adult resident; 3,220
cm2 for a child resident (aged 0 to 6] [USEPA. 1989cl).
T Exposure interval (sec) (7.9 x 10* sec (25 years) for a base worker; 9.5 x 10* sec [30 years) for residents).
TEF Toxicity equivalency factor for carcinogenic polynuclear aromatic hydrocarbons (PAHs) (Table 3.10); not
applicable for other constituents.
UC, Unit conversion 1 (10"*kg/mg).
UC, Unit conversion 2 (10"1 mVcm1).
UC, Unit conversion 3 (3,600 sec/hour).
Um Wind speed (4 m/sec (NOAA. 1974]).
Ut Equivalent threshold value of windspeed at 10 meters (12.8 m/sec).
VF Volatilization factor (site- and constituent-specific) (m*/kg).
Sample Calculation: Cancer Effects of Chrysene (base worker)
SExD (160 mg/kg) x (SO mg/d) x (12 d/yr) x (25 yrs) x (10r* kg/mg)
0 (7Okg) x (25.550d)
- 1.34 x 10-* mg/kg/d
TF07IM01 l\D«.i
-------
TABLE 2-15
EQUATIONS AND SAMPLE CALCULATIONS FOR SOIL EXPOSURE
SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR RESERVE BASE, FLORIDA
(Page 3 of 4)
SExD nSOmg/tcQ) x (3.160cm*) x (1 mg/cm'/d) x (0.03) x (12d/yr) x (25yrs) x (1Q-*kg/mg|
" (70kg) x (25,550d)
- 2.54 x 10-* mg/kg/d
Dei - (0.04531 cm'/sec) x (0.06X3V0.43*) 2.09 x 10** cmj/sec
Kas - (41 mol/atm/mj) x (3.15 x 1Q-7atm-ma/mol) , 2 69 x 10** a/cm3
(240.000 cmj/g) x (0.02)
a - (2.09 x 10-»cm»/sec)xO.Q6 ,.35 x 10-«cm'/sec
0.06 * l(2.65g/cm;i) x (1 -0.06)/(2.69 x 10-«g/cm3)l
sY - 0.02685 x fo.25 * nn(44.500m»)- 11.05091'] . Q.006836
[ 26.3608 I
Q;C - (exp( [ (0.1004 x ln(44.500m*]) - 5.3466J * (2.92 x 0.006836) })
- 70.25 (o/ma/sec)/(kg/m3)
VF - f-yr>7gQ/"ia/sec] ^ I3.1416x (1.36 x 1Q-»cm»/5ec) x (7.9 x 10«sec)l"»
[ ' Ico/m3 j 2 x (2.09 x lO^cm'/sec) x 0.06 x (2.69 x 10-*g/cmJ)
- 1.91 x 10* ms/kg
jg g/m*/secl x 3,600 sec/hour
' kg/m3 J (0.036 g/mj/hr) x (1 -0) x | (4 m/scc)/( 12.8 in/sec) P x 0.01257
1.83 x 10" m»/kg
(70 kg) x (25,550 d)
1.Mx1Cr10
ELCR - (l(1.34x 10-*mg/kg/d) x (7.3kg-d/mg)| » 1(1.56 x 1 0-10mg/kg/d) x (6.1 kg-d/mg)]} x 0.01
- 9.8 x 10-«
(CSF, is not available for chrysene; therefore, dermal exposure is not included in the ELCR calculation.)
TO) 70401 t\O*B. IOO>VM
-------
TABLE 2-15
EQUATIONS AND SAMPLE CALCULATIONS FOR SOIL EXPOSURE
SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR RESERVE BASE, FLORIDA
(Page 4 of 4)
Sample Calculation: Non-Cancer Effects of Cobalt (adult resident)
SExD . (1.3mg/kg) x (100mg/d) x (350d/yr) x (30yrs> x (1Q-«kg/mg)
170kg) x (10,950d)
- 1.78x10-* mg/kg/d
SExD . (1.3mg/kg) x (4,650cm*) x (1 mg/cma/dl x 0.0011 x (350d/yr> x (30yrs> x (1Q-*kg/mg)
* (7Okg) x (10.950 d)
- 8.28 x 10-« mg/kg/d
SExD . Q^mfl/hB) x{0 *(1^.83x10loma/Ka)l x(O83m3/hO x(24hi/d) x QSOd/yr) x QOyra)
1 (70 »^)x (10,850 d)
- 1.94x10-"
H| m 1.78x 10"«mo/kg/d ^ 8.28 x 1Q-« mg/kg/d
6 x 10'a mg/kg/d 2 x 10*2 mg/kg/d
- 0.000034
(RfD,is not available for cobalt; therefore, inhalation exposure is not included in the HI calculation.)
-------
TABLE 2-16
EQUATIONS AND SAMPLE CALCULATIONS FOR WADING EXPOSURE
SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR RESERVE BASE, FLORIDA
(Page 1 of 2)
Equation Definitions:
WExD.
EPC
x ED x EF x ET
BWx AP
_ x IR^ x ED x EF
BW x AP x DC,
WExD,
EPC- x SSA x PC x UC, x ED x EF x ET
BW x AP
^ x SSA x SAR x ABS x ED x EF
BW x AP x UC,
ELCR = t(WExD0 x CSF0) + (WExDd x CSFJ1 x TEF
HI = (WExD./RfD.) -t- IWExDa/RfD.)
where:
ABS Dermal absorption efficiency, constituent-specific (from Table 3.11).
AP Averaging period (equal to ED x 365 days/year for non-cancer effects; 25,550 days [70 years x 365
days/year) for cancer effects) (USEPA, 1991 a).
BW Body weight (70 kg for an adult; 38 kg for an older child [aged 6 to 15 years! (USEPA, 1991 a; USEPA,
1989c).
CSF. Cancer slope factor adjusted to an absorbed dose (kg-day/mg) (from Table 3.10).
CSF. Cancer slope factor for oral exposure (kg-day/mg) (from Table 3.10).
ED Exposure duration (25 years for a base worker; 9 years for an older child (aged 6 to 15 years!).
EF Exposure frequency (12 days/year).
ELCR Excess lifetime cancer risk (unities*).
EPC.. Constituent exposure point concentration in the surface water (mg/U (Table 3.4).
EPC* Constituent exposure point concentration in the sediment (mg/kg) (Table 3.4).
ET Exposure time (8 hours/day for a base worker; 2.6 hours/day for an older child).
HI Hazard index (unities*).
IR^ Incidental ingestion rate of sediment while wading (5 mg/day).
IR_ Incidental ingestion rate of surface water while wading (0.005 liters/hour).
PC Permeability constant (cm/hour) (from Table 3.111.
RfD. Reference dose adjusted to an absorbed dose (mg/kg/day) (from Table 3.9).
RfD. Reference dose for oral exposure (mg/kg/day) (from Table 3.9).
SAR Sediment adherence rated mg/cm'/day) (USEPA. 1992b).
SSA Exposed skin surface area (3,120 cm2 for a base worker; 3,715 cm2 for an older child laged 6 to 15
years]) (USEPA. 199la; 1989O.
TEF Toxicrty equivalency factor for carcinogenic polynuclear aromatic hydrocarbons (PAHs); not applicable
for other constituents.
UC, Unit conversion 1 (10* mg/kg).
UC, Unit conversion 2 (10^ Ucm3).
WExD< Wading exposure dose from dermal contact (mg/kg/day).
WExD0 Wading exposure dose from incidental ingestion (mg/kg/day).
TFO 704011\Dn.lOOM«.A«r-»4
-------
TABLE 2-16
EQUATIONS AND SAMPLE CALCULATIONS FOR WADING EXPOSURE
SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR RESERVE BASE, FLORIDA
(Page 2 of 2)
Sample calculation - Bromodichlorometfiane. cancer effects, base worker:
WExD. =» (0.0020 mo/L) x (0.005 L/hrl x (25 vrs) x (12 davs/vr) x (8 hrs/davl
(70kg) x (25.550 days)
= 1.3x 10 mo/kg/da y
WExDj = (0.0020 mo/L) x (3.120cm2) x (5.8x 10'3cm/rir) x (lO'H/em*) x (25 vrs) x (12 davs/vr) * (8 hrs/dav)
(70 kg) x (25,550 days)
= 4.9 x 10'* mg/kg/day
ELCR - 1(1.3 x IQ-'mg/kg/day) x (0.062 kg-day/mg)! + 1(4.9 x 10"* mg/kg/day) x (0.062 kg/day/mg)]
= 3.8 x ia»
Sample Calculations - ohenarrthrene. non-cancer effects, child:
WExD. = (0.28 mo/ka) x (5 mo/dav) x (9 vrst x (12 davs/vr)
(38 kg) x (3.285 days) x (10* mg/kg)
= 1.2 x 10'* mg/kg/day
WExDd = (0.28 mo/kol x (3.715 cm2) x (1 mo/cm^/dav) x (0.03) x (9 vrs) x (12 davs/vr)
(38 kg) x (3.285 days) x (10* mg/kg)
= 2.7 x 10"* mg/kg/day
HI = 1.2 x 10'* mo/ka/dav + 2.7 x 10*moykQ/dav
3 x 10J mg/kg/day 3 x 102 mg/kg/day
= 9.4 x 10-7
-------
CSF. Use of the approach makes underestimation of the actual cancer risk highly unlikely.
Slope factors are derived from results of human epidemiological studies or chronic animal
bioassays to which animal to human extrapolation and uncertainty factors have been applied.
The CSFs for the carcinogenic contaminants of concern are contained in Table 2-17.
As an interim procedure until more definitive Agency guidance is established. Region IV
has adopted a toxicity equivalency factor (TEF) methodology for evaluating the carcinogenic
risks from PAHs. This methodology relates the relative potency of each individual
carcinogenic PAH to the potency of benzo(a)pyrene, the most carcinogenic PAH. The TEFs
for the PAHs are also presented in Table 2-17.
Other COPCs, including other PAHs and metals, may cause health problems other than
cancer. Reference doses (RfDs) have been developed by EPA for indicating the potential for
adverse health effects from exposure to contaminants of concern exhibiting non-carcinogenic
effects. RfDs, which are expressed in units of (mg/kg-day)-1, are estimates of lifetime daily
exposure levels for humans, including sensitive individuals, that are believed to be safe by
EPA. RfDs are derived from human epidemiological studies or animal studies to which
uncertainty factors have been applied (e.g., to account for the use of animal data to predict
effects on humans). Estimated intakes of COPCs from contaminated media can be compared
to their respective RfDs. The RfDs for the noncarcinogenic contaminants of concern are
provided in Table 2-18.
2.9.5 Risk Characterization
The centerpiece of the BRA is the risk characterization, which combines the other
components of the evaluation to estimate the overall risk from exposure to site
contamination.
In summary, the results of the BRA indicate that human health risks associated with potential
current and future land use scenarios at Site FT-5/OU-1 exceed EPA's and FDEPs target risk
range for protection of human health.
2.9.5.1 Carcinogenic Risk. For cancer causing compounds, risk is a probability that is
expressed in scientific notation. For example, an excess lifetime cancer risk of IxlO"6 means
that an individual has an additional 1 in 1,000,000 chance of developing cancer as a result of
site-related exposure over an estimated 70 year lifetime. EPA has established a target risk
28
-------
TABLE 2-17
CANCER SLOPE FACTORS, TUMOR SITES AND USEPA CANCER CLASSIFICATIONS
FOR CONSTITUENTS OF CONCERN.
SITE FT-6, FIRE PROTECTION TRAINING AREA NO. 2
Homestead Air Reserve Base, Florida
Constituent
CSF (mg/kg/day)M
Oral Adjustod(a] Inhalation TEF
Tumor site
Oral
Inhalation
USEPA
Classification
VOCs
Benzene
Bromodchloromethane
Methylene Chloride
BNA.S
Benzotaianthracene*
Benzo(b)fluoranthene*
Benzo(k)fluoranthene*
Benzo(a)pyrene
Butylbenzylphthalate
Carbozole
Chrysene*
Dlbenzo(a,h)anthracene*
lndeno(1.2,3-c,d)pyrene*
Pentachlorophenol
2.9E-02
6.2E-02
7.5E-03
5.8E-01
5.8E-01
5.8E-01
5.8E+OO
NA
2.0E-02
6.8E-02
5.8E+OO
5.8E-01
1JJE-01
2.9E-02
6.2E-02
7.5E-03
IAP
IAP
IAP
IAP
IAP
IAP
IAP
IAP
IAP
1.3E-01
2.9E-02
NA
1.6E-03
6.1E-01
6.1E-01
6.1E-01
6.1E+00
NA
NA
6.1E-02
6.1E+OO
6.1E-01
NA
0.1
0.1
0.1
1
-
_
0.01
1
0.1
leukemia
Kv&r
ttver
NA
NA
NA
stomach
NA
NA
NA
NA
NA
liver, adrenal gland
leukemia
NA
lung, liver
NA
NA
NA
respiratory tract
NA
NA
NA
NA
NA
NA
A
B2
B2
B2
B2
B2
B2
C
B2
B2
B2
B2
82
Pesticides
4.4'-DDD
4.4'.DDE
Heptachlor
Inorganics
Arsenic
Cadmium
Chromium VI
Lead
Nickel
References:
la]
2.4E-01
3.4E-01
9.1E+00
1.75E+00
NAP
NAP
NA
NAP
2.7E-01
3.8E-01
1.5E+01
1.8E+00
NAP
NAP
NA
NAP
NA
NA
9.1E+00
1.5E+01
6.1E+00
4.2E+01
NA
8.4E-01
liver
Ih/er
liver
skin
NA
NA
NA
NA
NA
NA
Irver
respiratory tract
respiratory tract
lung
NA
respiratory tract
B2
B2
B2
A
B1
A
B2
A
ATSDR. 1991c; IRIS, 1992; USEPA, 1992a,b.
The CSF adjusted to an absorbed dose was used to assess dermal exposure. The adjusted CSF was derived according
to
USEPA (1989a) methodology by dMdlng the oral CSF by the constituent-specific oral absorption efficiency (Table 3-8).
* The oral and Inhalation CSF was converted to an equivalent concentration of benzo(a)pyrene following the Interim
USEPA Region IV guidance on the toxlclty equivalency factor (TEF) methodology for carcinogenic PAHs (USEPA, 1992a).
Not applicable; the TEF Is relevant only for the carcinogenic PAHs.
IAP Inappropriate to adjust the oral CSF for carcinogenic PAHs to evaluate dermal exposure (USEPA, 1989a).
mg/kg/day Milligrams per kilogram per day.
NA Not available.
PAHs Potynudear aromatic hydrocarbons
TEF Toxlclty equivalency factor for carcinogenic PAHs
NAP Not applicable since It is carcinogenic by Inhalation only.
DOC.1003\Tabl8 2-17 REV. JUNE-1-B2 KK
-------
TABLE 2-18
REFERENCE DOSES FOR CONSTITUENTS OF CONCERN,
SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2
Homestead Air Reserve Base, Florida
Constituent
Oral RfD
(mg/kg/day)
Adjusted RfD*
(mg/kg/day)
Inhalation RfD
(mg/kg/day)
VOCs
Acetone
Benzene
Bromodichlorome thane
2-Butanone
Ethylbenzene
Methylene Chloride
Toluene
1,1,1-Trichloroe thane
Xylene
Acenaphthene
Acenaphthykne
Anthracene
Benzo(g,h,i)perylene
Butylbenzylphthalate
Carbozole
Dibenzofuran
Diethylphthalate
Fluoranthene
Fluorene
2-Metbylnapbthylene
Naphthalene
Pentachlorophenol
Phenanthtene
Pyrene
Pesticides
4,4'-DDD
4.4'-DDE
Heptachlor epoxide
Inorganics
l.OE-01
NA
2.0E-02
6.0E-02
l.OE-01
6.0E-02
2.0E-01
9.0E-02
2.0E+00
6.0E-02
3.0E-02
3.0E-01
3.0E-02
2.0E-01
NA
3.0E-02
8.0E-01
4.0E-02
4.0E-02
6.0E-02
4.0E-02
4.0E-03
3.0E-02
3.0E-02
3.0E-02
3.0E-03
7.0E-04
13E-05
l.OE-01
NA
2.0E-02
6.0E-02
l.OE-01
6.0E-02
2.0E-01
9.0E-02
2.0E+00
5.4E-02
2.7E-02
2.7E-01
2.7E-02
2.0E-01
NA
2.7E-02
8.0E-01
3.6E-02
3.6E-02
6.0E-02
2.7E-02
3.6E-03
3.0E-02
2.7E-02
2.7E-02
3.0E-03
6.0E-04
7.8E-06
NA
l.OE-04
NA
3.0E-02
2.9E-01
9.0E-01
1 .OE-01
3.0E-01
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
6.0E-O2
3.7E-04
3.7E-O4
NA
NA
NA
NA
NA
NA
Aluminum
Arsenic
Barium
Cadmium (foof)
Cadmium (water)
Chromium
Cobalt
Copper0
Iron
Lead
Manganese (food)
Mercury
Nickel
Vanadium
Zinc
NA
3.0E-04
7.0E-02
l.OE-03
5.0E-04
5.0E-03
6.0E-02
3.7E-02
NA
NA
1.4E-01
3.0E-04
2.0E-02
7.0E-03
3. OE-01
NA
2.9E-04
5.0E-03
2.0E-05
l.OE-05
l.OE-04
2.0E-02
2.2E-02
NA
NA
7.0E-05
5.0E-05
9.0E-03
7.0E-05
9.0E-02
NA
NA
1.4E-O4
NA
NA
NA
NA
NA
NA
NA
1.1E-04
9.0E-05
NA
NA
NA
Notes
c
NA
The RfD adjusted to an absorbed dose was used to assess dermal exposure. The adjusted RID was derived according to
USEPA (1989a) methodology by multiplying the oral RfD by the constituent-specific oral absorption efficiency (from Table
3-9).
n-Hexane is used as a surrogate for Cg to C2Q hydrocarbons.
Based on current drinking-water standard.
Not available.
References: ATSDR, 1991d; IRIS, 1992; USEPA, 1992a.
-------
range for DOD and Superfund cleanups of between lxl(H(l in 10,000) and IxlO'6.
However, the state of Florida's target risk is IxlO'6.
The formula used for calculating cancer risk is shown below:
Risk = GDI x CSF
where: Risk = a unitless probability of an individual developing cancer
GDI = chronic daily intake averaged over 70 years (mg/kg)
CSF = cancer slope factor, expressed as (mg/kg-day)-'
Potential current site risk for a base worker exposed to surficial soils results in a total site
excess lifetime cancer risk of IxlO'5.
The excess lifetime cancer risk for a hypothetical future adult and child resident exposed to
groundwater are 3x10~4 and 2xlO'4, respectively. The excess lifetime cancer risks for
hypothetical future adult and child residents exposed to soil at the site are IxlO'3 and 2xlO'3,
respectively. The cancer risk for the hypothetical future adult and child resident exceeds the
upperend for the risk range deemed protective of human health by USEPA and the FDEP.
Hazards due to non-carcinogenic chemicals: for compounds which cause toxic effects
other than cancer, EPA compared the exposure point concentration of a contaminant found at
the site with a reference does representing the maximum amount of a chemical a person
could be exposed to without experiencing harmful effects. The ratio of the average daily
intake to the reference dose is called a hazard quotient (HQ). The formula for calculating the
HQ is shown below:
Non-cancer HQ = CDI/RfD
where GDI = chronic daily intake
RfD = reference dose
GDI and RfD are expressed in the same units (mg/kg-day)-1 and represent the same exposure
period (i.e., generally chronic, but also subchronic, or short-term).
The hazard index (HI) can be generated by adding the HQs for all contaminants of concern
that affect the same target organ (such as the liver) within a medium or across all media to
29
-------
which a given population may reasonably be exposed. In general, EPA considers an HI of
1.0 to be the maximum acceptable hazard.
The HI for a current base worker exposed to surficial soils is 0.005. The HI for the future
adult and child residents exposed to groundwater at Site FT-5/OU-1 are 10 and 40,
respectively. The HI for the future adult and child resident exposed to soils are 0.2 and 1,
respectively.
The non-cancer HI for hypothetical future adult and child resident exposure to groundwater
is above the USEPA risk benchmark of 1. Hypothetical future hazards for residents exposed
to soils (both an adult and a young child aged 0 to 6 years) are at or below the USEPA
benchmarks (0.2 and 1 for the adult and child, respectively).
2.9.5.2 Total Risk. The total site risk for the current base worker exposed to surficial
soils and to surface water and sediments is IxlO'5 and HI of 0.005. These risk values for
potential exposure do not exceed the USEPA risk benchmark of 10^4 for cancer risk and 1 for
non-cancer risk; however, they do exceed the FDEP benchmark of 10'6. The risk for
hypothetical future adult resident exposure to groundwater and soil is IxlO'3 and a total site
HI of 10. The cancer risk for soil and groundwater exceed USEPA and FDEP health-based
levels. The non-cancer risk also exceeds the USEPA benchmark of 1. Hypothetical future
cancer and non-cancer risk were calculated for a young child (age 0 to 6 years) exposed to
groundwater and soils and for an older child (aged 6 to 15 years) exposed to surface water
and sediments. The calculated cancer and non-cancer risks for the young child and the older
child were added to obtain the total site risk for a hypothetical child resident. The total site
risk for future child exposure to groundwater, soil, surface water, and sediment is 2 x 10'3
and an HI of 30. Both risks exceed USEPA and FDEP health based levels.
2.9.5.3 Risk from Lead Exposure. Based on the results from the USEPA LeadS model,
the lead concentrations in soil and groundwater at Site FT-5/OU-1 are unlikely to cause
adverse effects for young children.
2.9.6 Chemicals of Concern and Remedial Goal Option
COCs contribute significantly to a use scenario for a receptor that (a) exceeds a 10~4 total
carcinogenic risk, (b) exceeds an HI of 1, or (c) exceeds a state or federal chemical specific
ARAR. Chemicals need not be included if their individual carcinogenic risk contribution is
30
-------
less than IxlO6 or their non-carcinogenic HQ is less than 1. For this site, the relevant RGOs
are for TPH and PAHs.
RGOs are risk-based cleanup levels: they are developed by combining the intake levels to
each chemical receptor from all appropriate routes of exposure (i.e., inhalation, ingestion,
and dermal) and pathways within a scenario and rearranging the site specific GDI equations
used in the risk characterization to solve for the concentration term. RGOs are developed for
each medium, each land use, and each receptor type.
The RGOs are presented here in tabular form and include cleanup levels for the 1(H, 10'5,
and 10'6 levels for each COC, medium, and scenario and the HQs of 0.1, 1, and 10 levels as
well as any chemical-specific ARARs. A summary of the risk-based RGOs are presented in
Tables 2-19 through 2-21.
2.9.7 Uncertainties in the Risk Assessment
The risk estimates presented in the BRA are conservative estimates of the risks associated
with current and hypothetical future exposure to media at the site. Actual risks are almost
certainly lower than those presented. Further, there is considerable uncertainty inherent in
the risk assessment process. Sources of uncertainty can be summarized as follows:
Environmental sampling may not fully identify constituent distribution.
Exposure doses calculated for hypothetical future scenarios do not take into account natural
attenuation processes that will reduce constituent concentrations and the likelihood of
exposure.
Toxicity values and other toxicologic information used to calculate risks are associated with
significant uncertainty; most information has been developed using laboratory animals
exposed to high doses.
Sufficient toxicological data may not be available for all detected constituents. As a result,
surrogate compounds were used to evaluate PAHs and petroleum hydrocarbons.
Non-carcinogenic risks associated with potential lead exposure were evaluated differently
from other COCs in the risk assessment.
31
-------
TABLE 2-19
RISK BASED REMEDIAL GOAL OPTIONS FOR SOIL
BASED ON POTENTIAL CURRENT BASE WORKER EXPOSER
SITE FT-S, FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR FORCE BASE, FLORIDA
(Page 1 of 2)
Constituents
VOCs
Acetone
Bromodichloromethane
2-Butanone
Eihylbenzene
Meihylene chloride
SVOCs
Acenaphthene
Acenaphlhylene
Anthracene
Benzo(a)anthracene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Benzo(a)pyrene
Benzo(g,h,i)perylene
Butylbenzylphthalate
Carbazole
Chrysene
Dibenzofuran
Dibenzo(a,h)anthracene
Fluoranthene
Fluorene
n-Hexane*
Indeno( 1 ,2,3-c,d)pyrene
2-Methylnaphthalene
Naphthalene
Pentachlorophenol
Phenanathrene
Pyrene
EPCss
THI:
12
0.16
0.15
16
0.18
35
4
77
160
140
90
100
56
12
58
160
13
19
360
35
2,900
64
92
49
16
340
250
Non-Cancer Risk-Based
0.1
260,000
--
790,000
230,000
--
78,000
44,000
440,000
-
--
--
--
44,000
520,000
--
44,000
-
48,000
48,000
160,000
--
29,000
17,000
«
44,000
44,000
1
2,600,000
-
7,900,000
2,300,000
780,000
440,000
4,400,000
--
--
--
--
440,000
5,200,000
--
440,000
-
480,000
480,000
1,600,000
--
290,000
170,000
--
440,000
440,000
RGOs
10
26,000,000
--
79,000,000
23,000,000
--
7,800,000
4,400,000
44,000,000
--
--
--
--
4,400,000
52,000,000
--
4,400,000
-
4,800,000
4,800,000
16,000,000
--
2,900,000
1,700,000
--
4,400,000
4,400,000
Cancer
| 0.000001
1,200
--
7,500
..
--
--
160
160
160
1 16 |
-
3,700
1,600
--
1 16 |
--
-
160
--
--
28
-
--
Risk-Base
0.00001
__
12,000
--
--
75,000
..
--
--
1,600
1,600
1,600
160
--
--
37,000
16,000
-
160
-
--
--
1,600
--
280
--
RGOs
0.0001
._
120,000
-
--
750,000
..
--
--
16,000
16,000
16,000
1,600
--
--
370,000
160,000
~
1,600
-
--
--
16,000
--
2,800
--
-------
TABLE 2-19
RISK BASED REMEDIAL GOAL OPTIONS FOR SOIL
BASED ON POTENTIAL CURRENT BASE WORKER EXPOSER
SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR FORCE BASE, FLORIDA
(Page 2 of 2)
Constituents
Pesticides
4,4'-DDD
4,4-DDE
Inorganics
EPCss
Non-Cancer Risk-Based RGOs
0.34
0.034
Cancer Risk-Base RGOs
THI:
0.1 1
10
0.000001
0.00001
0.0001
150
110
1,500
1,100
15,000
11,000
Aluminum
Arsenic
Barium
Cobalt
Chromium
Copper
Iron
Lead
Manganese
Mercury
Nickel
Vanadium
Zinc
7,300
8.6
48
1.4
36
10
8,400
980
140
0.022
7.8
7.8
91
6,400,000
160,000
210,000
120,000
250,000
120
--
4,100
1,100,000
64,000,000
1,600,000
2,100,000
1,200,000
2,500,000
1,200
-
41,000
11,000,000
640,000,000
16,000,000
21,000,000
270,000 2,700,000 27,000,000
12,000,000
25,000,000
12,000
13,000,000 130,000,000 1,300,000,000
410,000
110,000,000
Concentrations are given in milligrams per kilogram (mg/kg)
Risk-based RGOs which are less than the current EPCss are indicated with a cell border
RGO not available or not applicable
' n-Hexane is a surrogate for petrolem hydrocarbons
EPCss Exposure point concentration in surficial soil (from G&M, 1994b)
RGO Remedial goal option
TCR Target cancer risk
THI Target hazard index
Source: Geraghty and Miller, 1994b
-------
TABLE 2-20
RISK BASED REMEDIAL GOAL OPTIONS FOR SOIL
BASED ON HYPOTHETICAL FUTURE ADULT RESIDENT EXPOSURE
SITE FT-S, FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR FORCE BASE, FLORIDA
(Page 1 of 2)
Constituents
EPCss
Non-Cancer Risk-Based RGOs
Cancer Risk-Base RGOs
THI:
0.1
1
10
VOCs
Acetone 12
Benzene 0.21
Bromodichloromethane 0.16
2-Butanone 0.8
Eihylbenzene 3.3
Methylene chloride 0.21
Xylenes 2.5.
SVOCs
Acenaphthene 61
Acenaphthylene 4
Anthracene 190
Benzo(a)anthracene 190
Benzo(b)fluoranthene 210
Benzo(k)fluoranthene 120
Benzo(a)pyrene 150
Benzo(g,h,i)perylene 72
Butylbenzylphthalate 52
Carbazole 66
Chrysene 210
Dibenzofuran 25
Dibenzo(aji)anthracene 24
Fluoranthene 440
Fluorene 82
n-Hexane' 680
Indeno(l,2,3-c,d)pyrene 81
2-Methylnaphthalene 34
Naphthalene 64
Pentachlorophenol 21
Phenanathrene 410
Pyrene 320
5,000 50,000 500,000
15,000 150,000 1,500,000
4,300 43,000 430,000
100,000 1,000,000 10,000,000
1,600 16,000
910 9,100
9,100 91,000
910
1,000
910
1,000
1,000
3,000
580
330
910
910
9,100
10,000
9,100
10,000
10,000
30,000
5,800
3,300
9,100
9,100
160,000
91,000
910,000
91,000
100,000
91,000
100,000
100,000
300,000
58,000
33,000
91,000
91,000
0.000001 0.00001
24
19
120
2.3
0.54
240
190
1,200
23
5.4
0.0001
2,400
1,900
12,000
2.3
2.3
2.3
0.23
23
23
23
2.3
230
230
230
23
58
23
~
0.23
580
230
2.3
5,800
2,300
| 23
230
54
-------
TABLE 2-20
RISK BASED REMEDIAL GOAL OPTIONS FOR SOIL
BASED ON HYPOTHETICAL FUTURE ADULT RESIDENT EXPOSURE
SITE FT-S, FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR FORCE BASE, FLORIDA
(Page 2 of 2)
Constituents
EPCss
Non-Cancer Risk-Based RGOs
Cancer Risk-Base RGOs
THI:
1
10
0.000001
0.00001
0.0001
Pesticides
4,4'-DDD
4,4-DDE
Heptachlor epoxide
Inorganics
0.34
0.034
0.26
2.6
1.8
26
18
0.022
0.22
260
180
2
Aluminum
Arsenic
Barium
Cadmium
Chromium
Cobalt
Copper
Iron
Lead
Manganese
Mercury
Nickel
Vanadium
Zinc
4,500
6
29
0.86
24
1.3
7.6
4,900
330
81
0.021
6.6
6.9
48
--
--
3,100
3,800
2,000
4,900
2.7
--
90
19,000
--
~
31,000
38,000
20,000
49,000
27
-
900
190,000
..
| 0.93
310,000
26,000
3,800
380,000
200,000
490,000
270
190,000
9,000
1,900,000
..
9.3 93
260,000 2,600,000
38,000 380,000
--
1,900,000 19,000,000
-.
-- --
Concentrations are given in milligrams per kilogram (mg/kg)
Risk-based RGOs which are less than the current EPCss are indicated with a cell border
RGO not available or not applicable
1 n-Hexane is a surrogate for petrolem hydrocarbons
EPCss Exposure point concentration in soil (Table 3.3)
RGO Remedial goal option
TCR Target cancer risk
THI Target hazard index
Source: Geraghty and Miller, 1994b
-------
TABLE 2-21
RISK BASED REMEDIAL GOAL OPTIONS FOR SOIL
BASED ON HYPOTHETICAL FUTURE CHILD RESIDENT EXPOSURE
SITE Fr-5, FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR FORCE BASE, FLORIDA
(Page 1 of 2)
Constituents
VOCs
Acetone
Benzene
Bromodichloromethane
2-Butanone
Ethylbenzene
Melhylene chloride
Xylenes
EPCss
THI:
12
0.21
0.16
0.8
3.3
0.21
2.5
Non-Cancer Risk-Based RGOs
0.1 1
670 6,700
..
..
2,500 25,000
610 6,100
..
13,000 130,000
10 I
67,000
-
-
250,000
61,000
' -
1,300,000
Cancer Risk-Base
0.000001 0.00001
19 190
13 130
-
..
88 880
RGOs
0.0001
1,900
1,300
-
8,800
--
SVOCs
Acenaphthene 61
Acenaphthylene 4
Anthracene 190
Benzo(a)anthracene 190
Benzo(b)fluoranthene 210
Benzo(k)fluoranthene 120
Benzo(a)pyrene 150
Benzo(g,h,i)perylene 72
Butylbenzylphthalate 52
Carbazole 66
Chrysene 210
Dibenzofuran 25
Dibenzo(a,h)anthracene 24
Fluoranthene 440
Fluorene 82
n-Hexane* 680
Indeno(l,2,3-c,d)pyrene 81
2-Methylnaphthaiene 34
Naphthalene 64
Pentachlorophenol 21
Phenanathrene 410
Pyrene 320
300
160
1,600
160
1,300
160
190
190
3,000
1,600
16,000
1,600
13,000
1,600
1,900
1,900
4,000
1,100
670
1,600
1,600
30,000
16,000
160,000
16,000
130,000
16,000
19,000
19,000
40,000
11,000
6,700
16,000
16,000
1.2
1.2
1.2
0.12
12
12
12
1.2
120
120
120
12
12
0.78
7.8
39
12
390
120
..
0.12
1.2
3,900
1,200
12 I
120
78
-------
TABLE 2-21
RISK BASED REMEDIAL GOAL OPTIONS FOR SOIL
BASED ON HYPOTHETICAL FUTURE CHILD RESIDENT EXPOSURE
SITE FT-5, FIRE PROTECTION TRAINING AREA NO. 2
HOMESTEAD AIR FORCE BASE, FLORIDA
(Page 2 of 2)
Constituents
EPCss
Non-Cancer Risk-Based RGOs
Cancer Risk-Base RGOs
Pesticides
4,4'-DDD
4,4-DDE
Heptachlor epoxide
Inorganics
THI:
0.1
1
10
0.34
0.034
0.26
0.000001
0.00001
0.0001
2.4
1.7
0.027
24
17
0.27
240
170
3
Aluminum
Arsenic
Barium
Cadmium
Chromium
Cobalt
Copper
Iron
Lead
Manganese
Mercury
Nickel
Vanadium
Zinc
4,500
6
29
0.86
24
1.3
7.6
4,900
330
81
0.021
6.6
6.9
48
.
450
450
230
780
0.67
21
2,200
--
--
4,500
-
--
4,500
2,300
--
7,800
6.7
--
210
22,000
--
-
45,000
--
-
45,000
23,000
--
-
78,000
67
--
2,100
220,000
-
| 0.51
--
27,000
4,100
--
--
--
--
--
-
200,000
--
"""
--
1 5.1 |
270,000
41,000
--
--
--
--
--
2,000,000
~~
-
51
2,700,000
410,000
-
--
-
-
-
20,000,000
-
"
Concentrations are given in milligrams per kilogram (mg/kg)
Risk-based RGOs which are less than the current EPCss are indicated with a cell border
RGO not available or not applicable
' n-Hexane is a surrogate for petrolem hydrocarbons
EPCss Exposure point concentration in soil (Table 3.3)
RGO Remedial goal option
TCR Target cancer risk
THI Target hazard index
Source: Geraghty and Miller, 1994b
-------
There is considerable uncertainty associated with the toxicity of mixtures. The risk
assessment assumes that toxicity is additive; the mixture of constituents present has neither
synergistic nor antagonistic interaction; and that all of the constituents have the same
mechanism of action in the same target organ to produce the same toxic endpoints.
The use of conservative assumptions and models and the conservatism built into the RfDs
and CSFs are believed to result in an overestimate of risk. Therefore, actual risk may be
much lower than the estimates presented in the BRA but are unlikely to be greater.
2.9.7.1 Ecological Risks. Conditions at OU-1 provide little usable or preferred habitat
for terrestrial species. Limited vegetation is available for food or cover and the shallow
depth of soil to bedrock restricts the activities of burrowing animals. While avian species
may visit the site, it is highly unlikely that they would derive a significant portion of their
diet from the limited resources available. The potential water hazards to aquatic life from
groundwater contaminants being transported and discharged to surface water bodies (i.e., the
OU-1 drainage canal or the Boundary Canal) are considered low due to dilution and mixing.
The limited distribution of contaminants in the canal sediments also indicated a low potential
for ecological effects to aquatic organisms.
Four state threatened plant species (pine fern, brake fem, southern shield fern, and tetrazygia)
were identified along the drainage ditch comprising the south and east boundaries of Site
FT-5/OU-1. The occurrence of special status species is of concern due to their limited
numbers and precarious state of existence. However, in view of the limited extent of soil and
sediment contamination at Site FT-5/OU-1, it is unlikely that contamination is present in the
areas inhabited by these threatened species.
2.10 DESCRIPTION OF ALTERNATIVES
The USAF initially considered seven alternatives in the Feasibility Study (FS) to address the
soil and groundwater contamination identified at OU-1. The seven alternatives were
screened based on the criteria of effectiveness, implementability, and cost. Four of the most
promising alternatives were carried forward through complete evaluation. These four
alternatives were then evaluated against the nine CERCLA criteria requirements for selecting
a remediaJ alternative. These nine criteria include effectiveness, implementability, cost, state
acceptance, community acceptance, long-term effectiveness and permanence, reduction of
mobility, toxicity, or volume through treatment, compliance with ARARs, short term
32
-------
effectiveness, and overall protection of human health and environment. A summary of the
four alternatives is presented below while each is described in greater detail in the FS.
It should be noted that estimated costs for some of the alternatives presented herein differ
from those presented in the September 1994 Final Feasibility Study Report. These costs
differences arise primarily from the reduced cost of disposal to a municipal landfill (where
applicable) with respect to the cost of disposal in a RCRA hazardous waste disposal facility.
2.10.1 Alternative 1 - No-Action with Groundwater Monitoring of Contaminants
for Migration and Attenuation
The No-Action Alternative is evaluated as required by the National Oil and Hazardous
Substances Pollution Contingency Plan (NCP), the regulation implementing CERCLA, for
comparison with other alternatives. Semiannual groundwater monitoring would be
conducted for two years under the No Action Alternative on six existing monitor wells to
monitor migration and attenuation of groundwater contaminants. After the two year
monitoring program is completed, review of the site would be performed to evaluate the
contaminant migration and attenuation. Per CERCLA, site reviews every 5 years would be
conducted as part of this alternative since COCs exceeding USEPA target risk ranges would
remain on-site. The groundwater monitoring program may be discontinued after the 5-year
site review, if contamination is below health-based levels.
The present-worth cost of this alternative is estimated at $522,000 with capital costs of
$27,000 and an annual operation and maintenance (O&M) cost of $29,500.
2.10.2 Alternative 2 - Access Restrictions for Groundwater, Use Restrictions for
Soil, and Groundwater Monitoring of Contaminant Migration and
Attenuation
This alternative includes access restrictions that would prevent placement of potable wells in
the contaminated groundwater beneath OU-1. Groundwater monitoring would be conducted
to monitor the migration and natural attenuation of the contaminant plume. Zoning
restrictions by deed would also be utilized to prevent schools, playgrounds, hospitals, and
residential units from being built at OU-1 to limit exposure to adults and children. This
alternative would also prevent the practice of continued disposal of rubble at the site.
Groundwater monitoring would be performed semiannually for 2 years followed by a review
to evaluate contaminant migration and attenuation to below levels of concern. Natural
33
-------
attenuation is expected to degrade the contaminants below levels of health and environmental
concerns within 2-5 years. Review of the site would be conducted at least every 5 years to
ensure that the remedy continues to provide adequate protection of human health and the
environment.
The present-worth cost of this alternative is estimated at $330,000 with capital costs of
$55,000 and an annual O&M cost of $58,800. The reduction in estimated costs compared
with those reported in the Feasibility Study are attributed to the reduced duration of the
groundwater monitoring program.
2.10.3 Alternative 3 - Access Restriction for Groundwater, Use Restriction for Soil,
Treatment of Rubble and Topsoil, and Groundwater Monitoring of
Contaminant Migration and Attenuation
This alternative would include all the factors previously discussed in Alternative 2 with the
addition of treatment and disposal of the rubble pile and topsoil. The rubble pile, along with
the top 6 inches of weathered bedrock would be excavated and treated onsite or transferred to
a recycling facility where it would be burned. Five year site review is included because
contaminated (above EPA target levels) soils would remain onsite.
The present-worth cost of this alternative is estimated at $7,150,00 with capital costs of
$6,655,000 and an annual cost O&M cost of 58,800.
2.10.4 Alternative 4 Access Restrictions for Groundwater, Use Restrictions for
Soil, Treatment and/or Disposal of Rubble Pile and Topsoil, and
Groundwater Monitoring of Contaminant Migration and Attenuation
This alternative includes institutional controls which include all factors previously discussed
in Alternative 2, as well as disposal and potential treatment of the rubble pile, treatment of
the topsoil, and groundwater monitoring. The soil disposal option includes excavating the
rubble pile and the top 6 inches of native material (referred to as topsoil). Due to the
difference in nature of the rubble pile and the topsoil, they will be handled separately. The
34
-------
rubble pile, which likely consists only of construction debris, a non-hazardous waste, will be
disposed at a municipal waste landfill without any restrictions. The topsoil which showed
low levels of PAHs, will require additional characterization prior to disposal. If after further
characterization the topsoil is found to be chemically impacted, it will be treated by thermal
desorption. It has been assumed that the topsoil will require treatment while the rubble pile
will be disposed at a municipal waste landfill. Engineering fill, imported from offsite, would
be backfilled to replace topsoil.
The present-cost of this alternative is estimated at $3,161,316 with capital costs of
52,509,570 and O&M costs of $70,000.
2.10.5 Alternative 5 - Treatment and/or Disposal of Rubble, Topsoil, and Hot Spot
Soils; In-Situ Biotreatment and Air Sparging of Groundwater; and
Groundwater Monitoring.
This alternative includes treatment and /or disposal of the rubble pile and topsoil as described
in Alternative 2. Some of the native oolite will also be excavated to provide source removal
in some highly contaminated areas (i.e., hot spots). This alternative also includes in-situ
biotreatment of the groundwater via air sparging at the site. Groundwater monitoring is
included to monitor the effectiveness of the alternative during and after treatment.
Bioremediation of the groundwater would be accomplished by installing air sparging wells to
supply the necessary oxygen to enhance bioremediation. The air sparging wells would be
installed at the perimeter of the groundwater plume, to prevent the spreading of the existing
plume. The resulting rise in groundwater elevation in the vicinity of the well could be used
to aid in hydraulic containment. Groundwater monitoring would occur both during and after
biological treatment, to monitor the effectiveness of this alternative.
The present-worth cost of this alternative is estimated at $4,629,610 with capital costs of
$2,911,186 and annual O&M costs of $58,800.
2.11 SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES
An evaluation and comparison of the alternatives are presented in Table 2-22. The
comparison is based on the nine key criteria required under the National Contingency Plan
and CERCLA Section 121 for use in evaluation of remedial alternatives by USEPA. The
nine criteria are as follows:
35
-------
TABLE 2-22
COMPARATIVE ANALYSIS OF REMEDIAL ALTERNATIVES FOR SITU l-T-5
(Page I of 4)
Criteria
Alternative 1
No Action with
Croundwaler Monitoring
Alternative 2
Access Restrictions for
atcr
Monitoring
Overall Protecliveness
Human Health Protection
- Direct Contact/
Soil Ingcsiion
Groundwater Ingcstion for Existing
Users
(Jroundwaicr Ingcsiion for Kuturc
Users
Environmental Protection
Compliance with ARARs
Chemical-Specific
Location-Specific
Action-Specific
Only current completed exposure
pathway is that or base worker cutting the
grass. Excess cancer risk is
conservatively estimated at IxlO*.
No risk of ingesting contaminated
groundwatcr. Ground water beneath site
is not used as a potable water supply.
Potential exists for ingcstion of
carcinogenic PAIIs contaminated
groundwatcr if future residential wells
arc located near present contamination.
Some potential exists lor contamination in
rubble pile, topsoil, and bedrock to reach
groundwatcr. Docs not restrict migration
of current groundwatcr contamination.
Benzene was delected in a ground water
sample collected from one well at a
concentration just above slate MCI, of I
ug/L. This alternative docs not actively
reduce concentration of benzene.
The Biscaync Aquifer is a sole source
aquifer. Non-degradation policy applies
There arc no action-specific ARARs
associated with this alternative.
Same as Alternative I.
Same as Alternative I
Access restrictions provide protection
against locating future wells in
contaminated groundwatcr.
Same as Alternative I.
Same as Alternative I. Access
restrictions reduce risks (o human health
until natural processes reduce benzene
concentration in groundwatcr to MCLs.
Same us Alternative 1.
Same as Alternative I.
Thermal treatment of rubble pile and
topsoil permanently destroys large
percentage of PAH contamination,
Excess cancer risk (o current worker
and potential future resident is reduced
to within acceptable levels by either
treatment or engineered controls.
Same as Alternative I.
Same as Alternative 2.
Reduces potential for constituents ot
concern to reach groundwaicr.
Groundwater contamination docs not
appear to be migrating.
Some as Alternative 2.
Same as Alternative I.
Same as Alternative 3.
Same as Alternative 1.
Same as Alternative 2.
Same as Alternative 3.
Same as Alternative 2.
Same as Alternative 1.
TCLP analysis of samples from nibhlc Same as Alternative 3.
pile would likely meet LDRs.
Thermal treatment ul rubble pile and
topsoil and in situ hioircattiu'iii ul
groundwatcr permanently destroys IIW
of the f'All contamination at the site
Exccss cancer risk to airienl worker
and potential future resident is cxpccU'
to be insignificant after rcincdi.ihon
Same as Alternative I
IVrmancnlly (educes usk u> less llun
1x10* by treating all cnvitomncnlu)
media of concern.
Significantly reduce* amccntiLihons ul
constituents of concern in all
environmental media of concern.
Would likely meet MCLs soona ilun
the other alternatives.
Same as Alternative 1
Same as Alternative 3
-------
TABLE 2-22
COMPARATIVE ANALYSIS OK REMEDIAL ALTERNATIVES FOR SITE FI-5
(Page 2 of 4)
Criteria
Alternative 1
No Action with
Groundwater Monitoring
Alternative 2
Access Restriclluns fur
Gruundwaler, Use Restriction fur Soils
and Groundwuter Monitoring
Alternative 3
Access Restrictions for Groundwuter,
Use Restrictions for Soils, Treatment
of Rubble and Topsoil, and
Croundwater Monitoring
Alternative 4
Access Restrictions for
(Croundwater, Use Restrictions Cur
Soils, Treatment und/or Disposal of
Rubble and Topsoil, and
Ground water Monitoring
Alternative 5
Thtrnial Treatment and/or l)i*pos;il
(if Rubble, Topsoil, and Hot Spot Soils,
In Situ Biolreatmenl of Groundwuter,
and GroundwatiT Monitoring
Other Criteria and Guidance
Long-Term KfTcctivencss and
Permanence
Magnitude of Residual Risk
- Direct Contact/
Soil Ingest ion
Groundwaier Ingcstion for Existing
Users
Groundwatcr Ingesiion for Future
Users
Adequacy and Reliability of Controls
Need for 5-Year Review
There are no TBCs applicable 10 soil
comaiiiinaiionatSiieFr-5. The 17-177U
regulations for total PAHs in groundwuter
will not be met for many years.
PAH contamination in soil is fairly
persistent. However, current access to
site is limited.
No risk of ingesting benzene-
contaminated ground water because the
groundwatcr is not used as potable water.
Potential exists for ingestion of
contaminated groundwater if future wells
ore located within contaminated
groundwater.
No controls over contamination. No
reliability.
Review would be required to ensure
adequate protection of human health and
the environment is mainuuned.
Concentrations of PAHs above health-
based levels for future hind use scenario
would remain onsite.
Same as Alternative I.
Same as Alternative I
Same as Alternative I
Current access to site is limited by normal
base operations. Potential future access
is limited by institutional controls. Risk
would be low because exposure
pathways are eliminated.
Same as Alleinative I.
Access restrictions provide protection
against locating future wells in
contaminated zone.
Future well placement controls required
for 10 years until the contaminated
groundwaier naturally mitigates.
Same as Alternative 1.
Same as Alternative 2. In addition, a
large percentage of the PAH
contamination is removed from the site
and permanently destroyed.
Same as Alternative 1.
Same as Alternative 2.
Same as Alternative 2.
Same as Alternative I.
Same as Alternative 3.
Same as Alternative 1.
Same as Alternative 2.
Same as Alternative 2.
Same as Alternative I.
hi siltt biurcmcdiaiioii ol Ik-dunk ami
groundwatcr will likely reduce ilie
concentration of constituent of concern
to below guidance levels within a few
years.
Residual mk is luw The cunceniralions
of constituent!) of Concern are
significantly rcJuccd.
Same as Alicmaiivc I
Permanently reduces risk to less than
1x10* by in situ biotreatment.
Hydraulic cuntainiiicMi must l>e
maintained during gioundwater
bioremediaiion.
None required.
-------
TABLE 2-22
COMPARATIVE ANALYSIS OF REMEDIAL ALTERNATIVES FOR SITE KI'-S
(Page 3 of 4)
Criteria
Alternative 1
No Action with
Ground water Monitoring
Alternative 2
Access Restrictions for
Ground water, Use Restriction for Soils,
and Groundwater Monitoring
Alternative 3
Access Restrictions For Groundwalcr,
Use Restrictions for Soils, Treatment
of Rubble and Topsoil, and
Groundwater Monitoring
Alternative 4
Access Restrictions for
Groundwater, Use Restrictions for
Soils Treatment and/or Disposal of
Rubble and Topsoil, and
Groundwater Monitoring
Alternative 5
Thermal Treatment and/or Disposal
of Rubble, Topsoil, and Hot Spot Soils,
In Situ Biolreatmenl of Groundwater,
and Groundwuter Monitoring
Reduction of Toxicily, Mobility, or
Volume Through Treatment
Amount Destroyed or Treated
Reduction of Toxicily, Mobility, or
Volume
Irreversible Treatment
Type and Quantity of Residuals
Remaining After Treatment
Short-Term Effectiveness
Community Protection
Worker Protection
Environmental Impacts
Time to Complete Action
None.
None.
Not applicable.
Not applicable.
No risk to community.
No risk to workers.
None.
Not Applicable.
None.
None.
Not applicable.
Not applicable.
Same as Alternative 1.
Same as Alternative 1.
None.
Not Applicable.
About 60 to 80 percent uf the VOCs and Same as Alternative 3.
PAHs in the soils is expected to be
removed from the site and destroyed by
thermal desorption.
Toxicily and volume ol contaminants in Same as Alternative 3.
rubble and topsoil reduced.
Thermal desorption permanently
removes VOCs and BNAs front lopsoil.
Treated topsoil is suitable for
replacement, road base, asphalt
batching, etc.
Same as Alternative I.
Workers will potentially be exposed to
VOCs via inhalation during excavation
Protective clothing will eliminate
potential risk.
None.
Excavation and disposal of rubble and
topsoil could be completed within 6
months. Natural attenuation of
chemicals in groundwater to below slate
and federal MCLs could take 1 to 5
years.
Same as Alternative 3.
Same as Alternative 3.
Same as Alternative I.
Same as Alternative I.
Same as Alternative 3.
Same as Alternative 3 In addition, I he
majority of the VOCs and BNAs in the
aquifer materials and groundwaier are
expected to be removed and destroyed
by the in silu biorcmediaiion.
To*icily and volume of cuni;iintii;int> in
all soils and groundwaicr reduced.
Thermal dcsorptiun permanently
removes VOCs and BNAs from lupMiil.
In situ bioremediaiion of grounthvutcr
permanently destroys ihc uxidi/.uble
orgunics.
Treiiieii tnp.soil i-, .suiKihlL' Im
replacement, road b;tic, asphalt
batching, etc. Residua) nitrates iinj
other biotesiduals may he left in the
groundwatet.
Same as Alternative 1
Same as Alternative 3.
Potential changes' to aquifer during
biorcmcdiation.
Six months to remove and treat rubble
and topsoil About two years to treat
bedrock and groundwaier.
-------
TABLE 2-22
COMPARATIVE ANALYSIS OK HliMtRlAL ALTERNATIVES FOR SITE FT-5
(P«Ce4of4)
Criteria
Implonicntabtlity
Ability lo Cons I rue I and Operate
Flexibility of Action
Ability lo Monitor Effectiveness
Ability lo Obtain Approvals
Availability of Services, Equipment, and
Materials
Availability of Technologies
Cost
Capital Cost
Annual O&M Costs
Present Worth Cosl
Alternative 1
No Action with
Groundwater Monitoring
Not Applicable.
Noi Applicable.
Proposed monitoring will provide notice
before significant exposure occurs.
No approvals necessary.
No special services, equipment, or
materials required.
None required.
$27,000
$29,500-58.800
$522.000
Alternative 2
Access Restrictions fur
Groundwater, Use Restriction
for Soils, and
Groundwater Monitoring
Access and use restrictions require
cooperation of local regulatory agencies.
The type and duration of access and use
restrictions cmi be relatively easily
modified.
Same as Alternative 1.
Same as Alternative 1.
Same as Alternative 1.
None required
$55,000
$29,500-58,800
S330.0UO
Alternative 3
Access Restrictions Tor
Groundwater, Use Rest He (ions fur
Soils,
Treatment of Rubble and Topsoil, and
Groumlwaler Monitoring
iixcavutkin and transportation ol 'nibble
and soils is easily implcincntable.
The volume and type of soil excavated
and treated is easily changed. On-siie
or off-site treatment units arc available
Same as Alternative 1
Same as Alternative 1.
Conventional excavation and
transportation equipment readily
available.
Thermal desurption is readily available
$6.7 million
$58.800
$7.2 million
Alternative 4
Access Restrictions fur
Groundwater, Use Restrictions fur
Soils, Treatment and/or Disposal of
Rubble and Topsoil, and
Groundwater Monitoring
Same as Alternative 3.
Same as Alternative 3
Same as Alternative 1.
Same as Alternative 1.
Same as Alternative 3.
Same as Alternative 3
U5 million
570,000
$3.2 million
Alternative 5
Thermal Treatment and/or Disposal
of Rubble, Topsoil, and
Hot Spot Soils, In Situ Bioircatnicnl of
(iroundwatcr, and Grounduater
Monitoring
Cotisituction and upeMiliun ol* in siti<
bioircatmcnt system is moderately
difficult to implement. Hydraulic
control must be established, Labuulury
studies, (feasibility study, and modeling
is required before final design
System can be designed in allow M»me
flexibility in the type ami ammrnt ol'
nutrients applied to the ground Some
flexibility can be designed into the air
sparging system.
Same as Alternative 1
Same as Alternative 1.
In situ biotreatmcnt system requites
specialists lo install, operate, and
monitor.
Vendors available
$2.9 million
$5K,8UO 265,200
$-1.7 million
-------
Overall protection of human health and the environment.
Compliance with Applicable or Relevant and Appropriate Requirements.
Long-term effectiveness and permanence.
Reduction of toxicity, mobility, or volume.
Short-term effectiveness.
Implementability.
Cost.
State acceptance.
Community acceptance.
2.11.1 Overall Protection of Human Health and Environment
Alternative 1 does not reduce the potential excess cancer risk to humans, nor does it provide
adequate protection to the environment. Alternative 2 utilizes institutional controls to
prevent exposure to contaminated soils/bedrock and groundwater which reduces the potential
excess cancer risk, while providing limited protection to the environment via natural
attenuation. Alternatives 3 and 4 significantly reduce the mass of contaminants in the nibble
and topsoil, which decreases the mass of constituents of potential concern in the soil which
could reach the groundwater, and implements institutional controls to prevent access to
constituents of potential concern until natural processes decrease the concentrations to below
health-based levels of concern. These alternatives provide some environmental protection by
eliminating a primary source of COCs. Alternative 5 reduces the potential excess cancer risk
to adults and children by destroying the organic constituents of concern in both soil and
groundwater. This alternative also provides protection to the environment by treating both
media of concern.
2.11.2 Compliance with ARARS
The important ARARs applicable at Site FT-5 are the state and federal MCLs and the
nondegradient policy for groundwaters of the state. Alternatives 1, 2, 3 and 4 do not actively
provide for groundwater treatment. It is expected that Alternatives 1 and 2 will meet ARARs
within 2 to 5 years because the benzene in the groundwater is expected to naturally attenuate
within that time frame. Similarly, the limited presence of PAHs in groundwater at Site FT-5
(detected at 1.5 times the MCL of 10 \ig/L in one sample) would also continue to naturally
attenuate. As discussed in Section 2.6.2.4, PAH concentrations in groundwater showed
marked decrease in concentration between 1990 and 1993 sampling events. Alternatives 3
36
-------
and 4 will result in accelerated attenuation of the COCs in the groundwater. Alternative 5
(off-site thermal treatment and in-situ biotreatment) actively treats the groundwater; the
concentrations of benzene is expected to decrease to below detection limits fairly rapidly
(within 1 year).
2.11.3 Long-term Effectiveness and Permanence
Alternatives 3 and 4 permanently destroy the constituents of concern in the rubble and
topsoil. Alternative 5 permanently destroys the constituents of concern in the rubble, topsoil,
bedrock, and groundwater.
2.11.4 Reduction of Mobility, Toxicity, or Volume Through Treatment
Alternatives 3 and 4 permanently reduce the toxicity and volume of the constituents of
concern in the rubble and topsoil, as well as reducing the mass of COCs that are mobilized
into the groundwater. Alternative 5 (off-site thermal treatment and in-situ biotreatment)
permanently reduces the toxicity and volume of the constituents of concern in the rubble,
topsoil, weathered bedrock, and groundwater.
2.11.5 Short-Term Effectiveness
None of the remedial alternatives are expected to cause significant risk to the community or
workers during construction and implementation. Alternatives 1 and 2 will meet ARARs
within 2 to 5 years, while Alternatives 3 and 4 will result in accelerated attenuation; and
Alternative 5 actively treats groundwater. Alternative 5 is expected to reduce groundwater
benzene concentrations to below detection limits within 1 year. There is essentially no
significant environmental impact from any of the alternatives.
2.11.6 Implementability
Alternatives 1, 2, 3, and 4 are easily implementable. The in-situ biotreatment in Alternative
5 requires laboratory tests and a treatability test before final design. In addition, computer
modeling must be performed during design to determine the optimum air sparging system
capable of maintaining hydraulic control. Pilot-scale testing is also recommended to
determine the optimal system configuration and potential adverse effects (such as well and
aquifer clogging).
37
-------
2.11.7 Cost
Alternatives 1 and 2 are the least costly alternatives with present worths estimated at
$522,000 and 5330,000, respectively. Alternative 2 assumes groundwater monitoring would
be performed semi-annually for two years and would have the additional administrative costs
associated with establishing the institutional controls. Alternative 3, which includes
treatment of the rubble and topsoil, costs approximately $7.2 million to implement and
results in a significant reduction of the contamination at the site. Alternative 4 (similar to
Alternative 3 but disposal of rubble and treated topsoil is to a municipal landfill) costs
approximately $3.2 million to implement, and also results in a significant reduction of
contamination at the site. Alternative 5, which includes disposal and/or thermal treatment of
the rubble and topsoil and in-situ biotreatment of the bedrock and groundwater costs
approximately $4.7 million to implement.
2.12 SELECTED REMEDY
Based upon consideration of the requirements of CERCLA, the detailed evaluation of the
alternatives and public comments, the U.S. Air Force in concurrence with the USEPA and
the State of Florida has determined that Alternative 2 - Access Restriction for Groundwater,
Use Restriction for Soil, and Groundwater Monitoring of Contaminant Migration and
Attenuation is the most appropriate course of action for Site FT-5/OU-1.
This alternative would achieve substantial risk reduction by controlling human exposure to
contaminants. The groundwater will be monitored semiannually for two years to assess the
migration and/or attenuation of contaminants. At the five year review, EPA, FDEP, and the
USAF will evaluate the need for further action. This alternative would be protective,
cost-effective, and would attain all Federal and State requirements. The selected remedy has
been accepted by the state and community concerns have been addressed in the
"Responsiveness Summary" of this ROD.
The present-worth cost of this alternative is estimated at $330,000 with capital costs of
$55,000 and an annual O&M cost of $58,800.
In accordance with CERCLA requirements for sites where contaminants remain in place
above EPA Target Levels, five year reviews of the site will be performed. If after the five
year review, the selected remedy has not effectively reduced contaminant levels to a quality
38
-------
that assures protection of human health and the environment, the EPA, FDEP, and Air Force
will evaluate the need for further action.
2.13 STATUTORY DETERMINATIONS
The selected remedy is protective of human health and the environment as required by
Section 121 of CERCLA. Existing or potential risks from exposure to soils and groundwater
are reduced and controlled through access restriction for groundwater use restrictions for
soils, and groundwater monitoring.
The selected remedy is expected to meet ARARs within 2 to 5 years because the benzene in
the groundwater is expected to naturally attenuate within that timeframe. Similarly, the
limited presence of PAHs in groundwater at Site FT-5 would also continue to naturally
attenuate.
Under current land use conditions, the COCs in the soil and groundwater pose an acceptable
risk to humans. Access restrictions would ensure that future exposure pathways for future
residents are not completed under this alternative.
Monitoring, maintenance, and control would be required under this alternative because the
contaminated soil would remain onsite and COCs in groundwater may remain above
health-based levels for many years.
This Alternative utilizes institutional controls to prevent exposure to contaminated
soils/bedrock and groundwater. The effectiveness of this alternative is subject to 5-year site
review.
This alternative does not actively reduce the mobility, toxicity, or volume of the COCs in the
soil or groundwater.
Cooperation between the USAF, USEPA, FDEP, and Dade County would be required to
enact the access and use restriction.
The selected remedy is cost effective because it has been determined to provide overall
effectiveness proportioned to its costs. The present net worth is estimated at $330,000.
39
-------
Neither Permanent Solutions nor alternative treatments were employed at this site due to the
minimal risks associated with the COCs present and the unlikely scenario of residential
development as well as associated costs for removal of site contaminants. The statutory
preference for treatment as a Principal Element is not met. However, use restrictions would
limit exposure until concentrations of COCs are below levels of concern.
2.14 DOCUMENTATION OF SIGNIFICANT CHANGES
The PP was released for public comment on November 1, 1994. The PP identified
Alternative 2, Access Restriction for Groundwater, Use Restriction for Soil, and
Groundwater Monitoring of Contaminant Migration and Attenuation, as the preferred
alternative for remedial action at Site FT-5/OU-1. Alternative 5 of the ROD (listed as
Alternative 7 of the September 1994 Final Feasibility Study Report) was excluded from the
November 7, 1994 Proposed Plan. The public was provided an opportunity for comment on
this alternative upon its inclusion in the ROD. Incorporation of this alternative is not
considered a significant change.
Alternative 3 of the ROD is a slight modification of the September 1994 Feasibility Study's
Alternative 4, and was presented under the nine-point criteria evaluation in the Proposal Plan
and ROD.
Responses to comments received during the November-December 1994 public comment
period are presented in the attached Responsiveness Summary. The public comment period
was reopened for thirty days (from March 14, 1995 to April 12, 1995) to provide the public
with an opportunity to comment on the addition of Alternative 5. A public notice was placed
in the South Dade News Leader on March 14, 1995, informing the public of the re-opening
of the public comment period for OU-1. No comments were received during this second
public comment period.
40
-------
Homestead Air Reserve Base, Florida
Operable Unit No. 1
Site FT-5, Fire Protection Training Area No. 2
Responsiveness Summary for the
Record of Decision
-------
RESPONSIVENESS SUMMARY
FOR THE
RECORD OF DECISION
The responsiveness summary serves three purposes. First, it provides regulators with
information about the community preferences regarding both the remedial alternatives and
general concerns about Operable Unit No. 1, Homestead ARB. Second, the responsiveness
summary documents how public comments have been considered and integrated into the
decision making process. Third, it provides EPA with the opportunity to respond to each
comment submitted by the public on the record.
The Remedial Investigation/Baseline Risk Assessment Report and the Proposed Plan for
Homestead ARB Site FT-5/OU-1 were released to the public in April and November of
1994, respectively. These documents were made available to the public in both the
administrative record and an information repository maintained at the Miami-Dade
Community College Library.
A public comment period was held from November 8, 1994 to December 23, 1994, as part of
the community relations plan of Operable Unit 1. Additionally, a public meeting was held on
Tuesday, November 29, 1994, at 7:00 pm, at South Dade High School. A public notice was
published in the Miami Herald and the South Dade News Leader on Tuesday,
November 22, 1994. At this meeting, the USAF, in coordination with EPA Region IV,
FDEP, and DERM were prepared to discuss the investigation, results of the Baseline Risk
Assessment, and the Preferred Alternative described in the Proposed Plan.
A second public comment period was opened for thirty days from March 14, 1995 to April
12, 1995. This comment period was reopened to provide the public with an opportunity to
comment on the addition of(Alternative 5 to the Record of Decision. No comments were
received during the second 30-day public comment period.
-------
Summary of Comments Received During The Public Comment Period
Comments received during the November-December 1994 public comment period and
November 29, 1994 public meeting are summarized below. No comments were received
during the second (March-April 1995) public comment period.
Comment: The Tropical Audubon Society would like to raise several concerns about the
redevelopment plans for Homestead Air Force Base.
First, there are serious pollution control concerns. Redevelopment of the Air Force Base may
include several public and private organizations doing work much like what the Air Force did
at the base. That is, the same hazardous wastes of aviation and related industry may be in use
- complicated by the new regulatory job of watching multiple polluters. Damage to fuel
storage tanks at the base during Hurricane Andrew suggests the risks of developing anything
other than clean industry in a potential hurricane path, especially on a wetlands site. New
construction runs the risks of stirring up pollution sites created in the past and building land
structures that change erosion patterns and cause pollutants to leach out of pollution sites.
Secondly, there are concerns about the integrity of the ecological setting. Any development
should preserve mangrove stands along the canals, preserve habitats for species affected by
land use changes and pollution, and preserve wilderness features in a bulk fuel storage site
and fuel pump houses.
There is groundwater contamination at least in a bulk fuel storage site and at fuel pump
houses.
Pollutants - including DDT and other pesticides, metals, and polycyclic aromatic
hydrocarbons - are at potentially harmful levels in surface water, sediment, and fish at the
base canals particularly the Boundary Canal.
Response: Redevelopment of Homestead Air Force Base is currently underway and
includes approximately one-third of the base having been transferred to the 482nd Fighter
Wing (Air Reserve) and the remaining two-thirds transferred to the Air Force Base
Conversion Agency (AFBCA) for transfer of the property. The AFBCA has conducted a
screening process to allow federal, state, and other eligible parties to submit expressions of
interest for reuse of the property. Redevelopment of the base will include aviation activities
due to the mission of the 482nd Reserve Fighter Wing. Public and private interests which
-------
may ultimately reside on the base will be required to comply with the same environmental
laws and regulations as other related industry in the state of Florida.
Disposal and reuse of Homestead ARB is intimately linked to the environmental
investigations, restoration, and compliance activities which are currently being carried out in
accordance with state and federal regulations. Sites which have been identified as being
contaminated are being scheduled for remedial action and/or are being restricted for future
use and development. Homestead ARB has been actively investigating potential sources of
contamination at the base since 1982. An extensive parameter list of target compounds has
been analyzed for in a variety of media ranging from soil/rock, groundwater, surface water,
and sediments, in order to determine the impacts of contaminants on human health and the
environment. Cleanup and closure of the various sites are being conducted under the
guidance of the USEPA-Region IV and the state of Florida. HARB has identified the base
canal systems as OU-9 which presently encompasses the Boundary Canal and many of the
interior canals at the base and are presently being evaluated in accordance with CERCLA.
The objectives of HARBs environmental restoration program, as defined in the BRAC
Cleanup Plan, are to:
Address areas of concern that were a result of Hurricane Andrew.
Reconstruct the resources and facilities required to go forward with an effective
environmental restoration program such as files, reports, buildings, etc.
Protect human health and the environment.
Comply with existing statutes and regulations.
Meet new commitments specified in the revised Federal Facilities Agreement (FFA)
and consent agreements with the FDEP.
Complete RIs as soon as practicable for each OU or other IRP site.
Identify all potential source areas.
Establish areas of no suspected contamination.
-------
Initiate removal actions, where necessary, to control, eliminate, or reduce risk to
manageable levels.
Characterize risks associated with releases of hazardous substances, pollutants,
contaminants, or hazardous wastes.
Develop, screen, and select remedial actions (RAs) that reduce risk in a manner
consistent with statutory requirements.
Commence with RAs for the IRP sites as practicable, with special consideration for
the impacts on the Everglades and the Biscayne Bay ecosystems.
The base has undergone an extensive survey of sensitive habitats, wetlands, and
identification of threatened and endangered species which are known to periodically or
permanently inhabit the base. No special designation species were identified at Site
FT-5/OU-1. Furthermore, previous usage of the site has rendered it in a developed, no longer
natural condition such that the site is predominated by weedy species.
Groundwater contamination has been identified at various locations throughout the base
including the bulk fuel storage area and the fuel pump houses. These sites are actively being
evaluated for remedial action and/or groundwater monitoring to limit the exposure to human
health and the environment. These petroleum contaminated sites are being evaluated in
accordance with the Florida Department of Environmental Protection, Petroleum
Contaminated Site Criteria Section 62-770 (formerly 17-770) Florida Administrative Code
(FAC).
Comment: In the technical report on the fire training area, no mention was made as to the
presence of metal associated with aircraft (aluminum, magnesium, etc.), found in the top soil.
An aircraft fuselage was used at the site for fire training purposes.
Response: Field investigations have been performed at OU-1 from 1984 to 1993 in order
to identify the nature and extent of contamination as a result of past practices. Numerous soil
and groundwater samples have been collected and analyzed for volatile organic compounds,
base neutral and acid extractable compounds, inorganic metals, cyanide, and
pesticides/PCBs. A regulatory review of the contaminant levels indicated that total PAHs
and benzene exceeded state and federal levels in one well. No metals were found above
health-based levels. Furthermore, a baseline risk assessment was performed in which the
-------
risks to potential receptors were quantified. The risk for both current and potential future
land use scenarios were above levels considered protective of human health and the
environment by USEPA and FDEP. Seven remedial alternatives were evaluated based on the
COC in accordance with the CERCLA screening procedures and a preferred alternative
selected. This information is documented in the administrative record and available for
public inspection.
Comment: Suggest the rubble pile be removed and contaminated soil be cleaned up and
disposed.
Response: Seven remedial alternatives, including disposal of the rubble pile and top soil,
were evaluated based on the chemicals and media of concern. These seven alternatives were
screened based on the criteria of effectiveness, implementability, and cost. Four of the most
promising alternatives were then carried forward and even further evaluated against the nine
criteria of CERCLA. Factors concerning the disposal of the rubble pile include long term
liability and disposal costs. The selected alternative (Access restriction for soil and
groundwater monitoring of contaminant migration and attenuation) does achieve substantial
risk reduction by controlling exposure by human contact and provides for groundwater
monitoring to assess the migration and attenuation of contaminants.
Comment: I'm not pleased that the site would be only checked for 5 years. The rate of
movement is unknown and what if it will not go away for 50 years or more.
Response: Based on the knowledge of the site contaminants, it is believed that the
concentrations of benzene and PAHs will naturally decrease (attenuate) below levels of
concern within this timeframe. In addition, long-term monitoring, maintenance, and control
would be required due to the fact that contaminants will remain on site. A review of the site
will continue at least every 5 years or until the levels of contaminants are at levels considered
protective of human health and the environment.
Comment: It would cost less to clean the site today than 5-10 or 30 years from now.
We really need to look more to the future than we have to the past.
Response: The USAF, USEPA, and FDEP have analyzed the alternatives and identified
key trade-offs among them. Furthermore, the long term effectiveness and related
considerations were evaluated. Based on a review of these factors the Base Closure Team
-------
has determined that access restriction for soil and groundwater monitoring of contaminant
migration and attenuation is the most appropriate method of remedial action for this site.
Comment: The BRAC Committee EPA RI/BRA should clean the area in question up. In
five years the chemicals could spread. Please save our neighborhood and family.
Response: The key elements to satisfy CERCLA remedial action include overall
protection of human health and the environment, compliance with state and federal
regulations, long-term effectiveness and permanence, reduction of mobility, toxicity, or
volume through treatment, short-term effectiveness, implementability, cost, state acceptance,
and community acceptance. Access restrictions reduce the level of exposure to humans and
groundwater monitoring will assess the migration and attenuation of contaminants. With the
flat groundwater gradient at the base, contaminants are not expected to migrate off site.
However, the monitoring program, will track the rate of migration and contaminant
concentrations and if corrective measures are required, they could be implemented to reduce
the threat to human health and the environment due to migration.
-------
RECORD OF DECISION BRIEFING
OPERABLE UNIT NO. 4, MOTOR POOL OIL LEAK AREA
HOMESTEAD AIR RESERVE BASE, FLORIDA
Operable Unit No. 4, identified as the Motor Pool Oil Leak
Area, is located in the west central portion of Homestead Air
Reserve Base (formerly Homestead Air Force Base) . The Motor Pool is
primarily used for cleaning, servicing and repairing utility
vehicles. In operation since the Base was reactivated in the
1950's, the Motor Pool Area is mostly asphalt covered and
surrounded on all four sides by a drainage ditch system. The
selected remedy includes institutional controls, including access
restrictions that would prevent placement of potable wells in the
contaminated groundwater beneath the unit; deed restrictions
limiting the use cf the property to non-residential dwelling
purposes, including the rrevertion of schools, playgrounds and
hospitals from being built at the site; and groundwater monitoring.
This remedial action is protective of human health and the
environment, complies with Federal and State requirements that are
legally applicable or relevant and appropriate to the remedial
action and is cost effective.
-------
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION IV
345 COURTLANO STREET. N.E.
ATLANTA. GEORGIA 3O365
SEP 7 1995
4WD-FFB
Certified Mail
Return Receipt Requested
Mr. Alan K. Olsen
AFBCA/DR
1400 Key Boulevard
Arlington, Virginia 22209
SUBJ: Record of Decision for Operable Unit 1
Fire Protection Training Area No. 2 /'
Homestead Air Force Base NPL Site
Homestead Air Reserve Base, Florida
Dear Mr. Olsen:
The U.S. Environmental Protection Agency (EPA) Region IV
has reviewed the'above referenced decision document and concurs
with the selected final remedy for remedial action at Operable
Unit Operable Unit l, Fire Protection Training Area No. 2, as
supported by the previously completed Remedial Investigation,
Baseline Risk Assessment and Feasibility Study Reports.
The selected remedy includes institutional controls,
including access restrictions that would prevent placement of
potable wells in the contaminated groundwater beneath the unit;
deed restrictions limiting the use of the property to non-
residential dwelling purposes, including the prevention of
schools, playgrounds and hospitals from being built at the site;
and groundwater monitoring. This remedial action is protective
of human health and the environment, complies with Federal and
State requirements that are legally applicable or relevant and
appropriate to the remedial action and is cost effective.
Punted on Recycled P.ipr
-------
It is understood that the selected remedy for Operable
Unit 1 is the final remedial action to address all media
potentially affected by past disposal practices at this unit
Sincerely,
cc:
Patrick M. Tobin
Deputy Regional Administrator
Mary Bridgewater, AFBCA
Capt. Ed Miller, AFCEE
Robert Johns, DERM
Glenn Kaden, AFCEE c/o AFBCA/ OL-Y
Eric Nuzie, FDEP
Humbert o Rivero, AFBCA/OL-Y (Homestead Air Reserve Base)
------- |