PB98-964007
EPA 541-R98-023
October 1998
EPA Superfund
Record of Decision:
Homestead Air Force Base
OU2
Homestead, FL
7/16/1998
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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
% REGION 4
? ATLANTA FEDERAL CENTER
f 61 FORSYTH STREET
ATLANTA, GEORGIA 30303-8960 '
*u
#96
CERTIFIED MAIL
RETURN RECEIPT REQUESTED
.x,
4WD-FFB
Albert Lowas
Director of Air Force Base Conversion Agency
1400 North Moore Street, Suite 2300
Arlington, VA 22209-2802
SUBJ: Record Of Decision-Operable Unit 2
Homestead Air Force Base NPL Site
Homestead, Florida
Dear Mr. Lowas:
The U.S. Environmental Protection Agency (EPA) Region IV has reviewed the subject
decision document and concurs with the selected remedy for the remedial action at Operable
Unit (OU) 2 at the former Homestead Air Force Base (HAFB). This remedy is supported by the
previously completed Remedial Investigation, Feasibility Study, and Baseline Risk Assessment
Reports.
The selected remedy consists of: excavation of contaminated soils, testing of excavated
soils to determine if it is a RCRA hazardous waste and appropriate offsite disposal, stabilization
of soils, long-term monitoring of the ground water, institutional controls of the area, and five-
year reviews. 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. The sediments and surface water in the drainage ditches
surrounding the site will be addressed as part of the Remedial Investigation of OU-9 (Boundary
Canal and associated drainage ditches). The determination to implement this course of action at
this site is consistent with the Comprehensive Environmental Response, Compensation, and
Liability Act (CERCLA) as amended by the Superfund Amendments and Reauthorization Act
(SARA) and the National Contingency Plan (40 CFR 300).
*
Concurrence with the Record of Decision (ROD) is conditioned on the express
understanding that the Air Force is committed to reaching an agreement with EPA Region IV
and the Florida Department of Environmental Protection (FDEP) that complies with EPA!s
April 21, 1998 Memorandum titled "Assuring Land Use Controls at Federal Facilities." We
reiterate, as we advised Air Force Regional Environmental Office representatives in our meeting
Internet Address (URL) http://www.epa.gov
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on May 21, 1998, our concurrence with this particular ROD is based on the understanding that
the Air Force is committed to entering a Memorandum of Agreement (MOA) consistent with the
above-referenced Land Use Control (LUC) Policy. Furthermore, once such an MOA is in place,
the Homestead Air Force Base BRAC Cleanup Team (BCT) will be expected to craft specific
provisions for Land Use Controls as part of the resulting Land Use Control Implementation Plan
for OU- 2, that will prohibit unrestricted property reuse.
As agreed upon at the May 21, 1998, meeting, we continue to hold the expectation that
final details will be worked out within 90 days after the date of this concurrence, resulting in an
MOA that fully complies with the LUC policy. As emphasized at that meeting, and counter to
the statement in the Air Force Regional Environmental Office's letter dated June 1, 1998, we
remain steadfast in our position that in the event an MOA is not reached within 90 days, we
reserve the right to reconsider this remedy, and will not be willing to concur on future
Homestead RODs that rely in whole or in part on Land Use Controls unless and until an
agreement is in effect.
EPA appreciates the level of effort that was put forth in the documents leading to this
decision. EPA looks forward to working with HAFB as we move towards final cleanup of the
National Priorities List (NPL) site.
If you have any questions, please call me at (404) 562-8651, or Doyle T. Brittain at
(404) 562-8549.
Sincerely,
Richard D. Green, Director
Waste Management Division
cc: Thomas J. Bartol, HAFB/AFBCA
John Mitchell, HAFB/AFRES
Jim Woolford, EPA/FFRO
Jorge Caspary, FDEP
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Although this remedy will reduce the concentrations of hazardous substances, pollutants,
or other contaminates remaining on site to below Health-Based Levels, a review of the
remedial action will be conducted 5 years after its commencement. The 5 year review is
conducted because there is concern that potential sources of contamination in areas
adjacent to OU-2 may exist since the area has not been fully characterized.
UNITED STATE AIR F
HOMESTEAD AIR F
By: AlanK. Olser( >^*WV VJw£^4^ Date:
Director, AFBCA
STATE OF FLORIDA
DEPARTMENT OF ENVIRONMENTAL PROTECTION
By: Eric S. Nuzie Date:
Federal Facilities Coordinator
U.S. ENVIRONMENTAL PROTECTION AGENCY, REGION IV
By: John H. Hankinson Date:
Regional Administrator
-111-
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DEPARTMENT OF THE AIR FORCE
AIR FORCE BASE CONVERSION AGENCY
18 Dec 96
MEMORANDUM FOR FDEP
ATTENTION: Jorge Caspary
FROM: AFBCA/OL-Y
29050 Coral Sea Blvd
Homestead ARB, FL 33039-1299
SUBJECT: OU-2 Record of Decision Signature Pages
1. Attached are two copies of the revised OU-2 Record of Decision and 3 copies of signature
pages for concurrence with the OU-2 ROD for Mr. Nuzie's signature. Please send 1 copy of the
revised ROD, the 3 signed signature pages and the EPA cover letter to Earl Bozeman for EPA
signatures.
Humberto Rivero, GS-13
Site Manager
Attachments
Revised OU-2 ROD
Signature Pages (3)
EPA Cover Letter
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Department of
Environmental Protection
Twin Towers Office Building
Lawton Chiles 2600 Blair Stone Road Virginia B. Wetherell
Governor Tallahassee. Florida 32399-2400 Secretary
October 17, 1997
Mr. Albert F. Lowas, Jr.
Acting Director
Air Force Conversion Agency
1700 N. Moore Street, Suite 2300
Arlington, Virginia 22209-2802
Dear Mr. Lowas:
The Florida Department of Environmental Protection agrees
with the Air Force's selected alternative for Operable Unit 2
(Site OT-11), Residual Pesticide Disposal Area at Homestead Air
Reserve Base.
The Record Of Decision specifies Excavation and Off-Site
Disposal of Soils, Access Restrictions for Groundwater, Site
Fencing, and Groundwater Monitoring Alternative at Site OT-11 as
a cost effective remedy that provides adequate protection of
public health, welfare, and the environment. The determination
to remediate the soil and monitor groundwater at Site OT-11 is
consistent with the Comprehensive Environmental Response,
Compensation, and Liability Act (CERCLA) as amended by the
Superfund Amendments and Reauthorization Act (SARA) and the
National Contingency Plan (40 CFR 300). Accordingly, the site
shall undergo a five-year review with the costs of the review to
be absorbed by the federal government.
We appreciate your continued cooperation and look forward to
an expeditious economic and environmental recovery of Homestead
Air Reserve Base.
.Sincerely,
Virginia B. Wetherell
Secretary
VBW/jrc
"Protect Conserve and Manage Florida's Environment and Natural Resources"
Printed on recycled paper.
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Florida Department of
Memorandum Environmental Protection
TO: Virginia B. Wetherell, Secretary
FROM: John M. Ruddell, Directoj
Division of Waste Management
DATE: October 17, 1997
SUBJECT: Homestead Air Reserve Base Superfund Site
Record of Decision for Site OT-11 Residual Pesticide
Disposal Area, Operable Unit 2.
Attached for your review and signature is a letter of
concurrence to Mr. Albert F. Lowas, Acting Director of the Air
Force Conversion Agency, regarding the Record of Decision (ROD)
for Site OT-11, Homestead Air Reserve Base. The ROD specifies
the selected remedial alternative as Excavation and Off-Site
Disposal of Soils, Access Restrictions for Groundwater, Site
Fencing, and Groundwater Monitoring.
Operable Unit No. 2 (Site OT-11), identified as the Residual
Pesticide Disposal Area, is located in the eastern portion of the
base and within a parcel of land known as the Cantonment Area
remaining under Air Force control. Site OT-11 covers
approximately 20 acres. From 1977 to 1982, site OT-11 was used
for the disposal of pesticide rinsate from equipment cleaning.
These diluted materials were sprayed or dumped over an
approximately 1 acre area. Chlorine bleach and ammonia were then
applied to accelerate the decomposition of the pesticide
compounds.
Site OT-11 is bordered by the Boundary Canal to the west,
the ammunitions storage area to the south, Taxiway B to the east
and by grasslands to the north. The portion of the base where
Site OT-11 is located has restricted access, limited only to base
personnel with specific duties in this area. There are no public
roadways that lead past Site OT-11; therefore,- incidental or
casual exposure to contamination is not likely at the site.
The site currently is heavily vegetated with grasses, small
trees, and bushes. The land is undeveloped and was used to store
pre- and post-Hurricane Andrew dirt/fill material.
Investigations conducted in 1991 and 1993 included the
collection of 37 soil/weathered rock samples from a similar
number of borings. Soil samples were collected from depths of 0
to 1 foot below land surface (bis).
"Protect. Conserve and Manage Florida's Environment and Natural Resources"
Printed on recycled paper.
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Ms. Virginia Wetherell
October 17, 1997
Page Two
The surface soil investigations have confirmed the presence
of base neutral/acid extractable (BNA) compounds, pesticides, and
metals in soils. No PCBs were detected above the Department's
soil remedial goals for military sites.
Likewise, two monitoring wells were installed to assess the
impact of the reported pesticide disposal practices on the
Biscayne Aquifer. Only BNAs were reported in groundwater above
state standards during the sampling and analysis event conducted
in 1993.
The sediments and surface water in the drainage ditches
surrounding the site will be addressed as part of the overall
Operable Unit 9 (Boundary Canal and Associated Drainage Ditches)
Remedial Investigation.
A Baseline Risk Assessment has been completed and determined
that due to the levels of constituents of potential concern in
soil, the total site risk for a hypothetical future resident
exceeds current FDEP and Dade County Department of Environmental
Resources Management (DERM) criteria of total excess lifetime
cancer risk of 1E-6; therefore, the previously described
alternative is warranted to address the contaminants of concern
at Site OT-11.
In addition, legal restrictions preventing the use of
groundwater for consumption and access to the parcel will be
outlined and described in a forthcoming Memorandum of Agreement
(MOA) between the USEPA, the Commanding Officer for the Homestead
Air Force Base, and the Department..These restrictions shall
remain in effect until the groundwater standards are met and
concurrence is obtained from the USEPA and the Department to
remove them.
A public meeting outlining the selected alternative was held
on Thursday September 18, 1995 at 7:00 PM at the South Dade High
School. Representatives of the US Air Force, EPA Region IV,
FDEP, and DERM participated in the meeting. Additionally, a
public notice was published in the Miami Herald and South Dade
News Leader on September 7, 1995. The comments received have been
adequately addressed and the Air Force has elected to proceed
with the Selected Remedial Alternative specified in the ROD.
I recommend that you sign the attached letter of
concurrence.
JMR/jrc
Attachment
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Replacement certification sheets for OU-2 RA Work Plan omitted from
Friday 12-December submittal.
Maria Houck
OHM Remediation Services Corp.
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PROFESSIONAL CERTIFICATION STATEMENT
Re: Final Remedial Action Work Plan
Operable tmit 2 (OU-2)/Site OT-11
Homestead Air Reserve Base
Dade County, Florida
This is to certify that this Final Final Remedial Action Work Plan, completed by OHM
Remediation Services Corp. (OHM), on 8 December 1997, for the benefit of the Air Force Center
for Environmental Excellence (AFCEE), has been prepared under my responsible charge,
supervision and direction, and meets the requirements of Section 472 of the Florida Statutes.
Stephen D. Offner, TTG.
State of Florida Registration No. 1406
8 December 1997
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FINAL
RECORD OF DECISION
FOR
OPERABLE UNIT 2
SITE OT-11, RESIDUAL PESTICIDE DISPOSAL AREA
HOMESTEAD AIR RESERVE BASE, FLORIDA
April 1996
Prepared for:
U.S. Army Corps of Engineers
Missouri River Division
Omaha District
Omaha, Nebraska
Prepared by:
Montgomery Watson
107 Mallard Street, Suite D
St. Rose, Louisiana 70087
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TABLE OF CONTENTS
Page
SECTION 1.0 SITE NAME, LOCATION, AND DESCRIPTION l
1.1 Operable Unit No. ZDescription 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
SEOTON 2.0 fflSTORY AM) EWORC^MEhTT ACTIVITIES 6
2.1 OU-2/SiteOT-ll 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 9
2.3.1 IRP Phase I - Record Search 9
2.3.2 IRP Phase n - Confirmation/Quantification 9
2.3.3 IRP Phase ffl - Technology Base Development 10
2.3.4 IRP Phase IV - Additional Investigations 10
2.3.5 1991 Remedial Investigation of Site OT-ll/OU-2 12
2.3.6 1993 Remedial Investigation of Site OT-ll/OU-2 12
2.4 Community Participation History 12
2.5 Scope and Role of Responsible Action 13
2.6 Summary of Site Characteristics 13
2.6.1 Nature and Extent of Contamination 14
2.6.1.1 Soil Contamination 15
2.6.1.2 Groundwater Contamination 18
2.6.1.3 Sediment Contamination 19
2.6.1.4 Surface Water Contamination 22
2.6.2 Summary 23
2.7 Summary of Site Risks. 25
2.8 Selection of Chemicals of Potential Concern 25
2.9 Exposure Assessment 25
2.9.1 Exposure Point Concentration 26
2.9.2 LandUse 26
2.9,3 Exposure Scenarios 26
2.9.4 Toxicity Assessment 27
2.9.5 Risk Characterization 28
2.9.5.1 Carcinogenic Risk 28
2.9.5.2 Non-Carcinogenic Risk 29
2.9.5.3 Total Risk 30
2.9.5.4 Risk from Lead Exposure 30
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TABLE OF CONTENTS
Page
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 33
2.10.2 Alternative 2-Access and Use Restriction for Soil,
Access Restriction for Groundwater, and Groundwater
Monitoring 33
2.10.3 Alternative 3-Institutional Controls, Capping, and
Groundwater Monitoring 34
2.10.4 Alternative 4-Excavation, Off-Site Disposal of Soils,
Access Restriction for Groundwater, and Groundwater
Monitoring 35
2.11 Summary of Comparative Analysis of Alternatives 36
2.11.1 Overall Protection of Human Health and Environment 36
2.11.2 Compliance with ARARs 37
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 38
2.11.7 Cost 38
2.12 Selected Remedy 38
2.13 Statutory Determinations 39
2.14 Documentation of Significant Changes 39
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LIST OF TABLES
Table Follows
No. ~ Title Page
2-1 Pesticides Stored at Homestead ARB 6
2-2 Analytical Results of Phase n Soil Samples Collected in 1986 at
Site OT-1 l/OU-2, Residual Pesticide Disposal Area, Geraghty & Miller 10
2-3 Analytical Results of Phase IV Soil Samples Collected in 1988 at Site
OT-1 l/OU-2, Residual Pesticide Disposal Area, Geraghty & Miller 11
2-4 Analytical Results of Phase IV Groundwater Samples Collected
in 1988 at Site OT-1 l/OU-2, Residual Pesticide Disposal Area,
Geraghty & Miller 11
2-5 Constituents Detected in Soil/Weathered Rock Samples Collected in 1991
at Site OT-1 l/OU-2, Residual Pesticide Disposal Area, Geraghty & Miller.. 15
2-6 Constituents Detected in Soil/Weathered Rock Samples Collected in 1993
at Site OT-1 l/OU-2, Residual Pesticide Disposal Area, Geraghty & Miller.. 15
2-7 Background Soil Concentrations 16
2-8 Constituents Detected in Groundwater Samples Collected in 1993
at Site OT-1 l/OU-2, Residual Pesticide Disposal Area, Geraghty & Miller.. 19
2-9 Constituents Detected in Sediment Samples Collected in 1991
at Site OT-1 l/OU-2, Residual Pesticide Disposal Area, Geraghty & Miller,.. 20
2-10 Constituents Detected in Sediment Samples Collected in 1993
at Site OT-1 l/OU-2, Residual Pesticide Disposal Area, Geraghty & Miller.. 20
2-11 Constituents Detected in Surface Water Samples Collected in 1991
at Site OT-1 l/OU-2, Residual Pesticide Disposal Area, Geraghty & Miller.. 22
2-12 Constituents Detected in Surface Water Samples Collected in 1993
at Site OT-1 l/OU-2, Residual Pesticide Disposal Area, Geraghty & Miller.. 22
2-13 Constituents of Potential Concern at Site OT-1 l/OU-2,
Residual Pesticide Disposal Area, Geraghty & Miller 25
2-14 Equations and Sample Calculations for Hypothetical Future
Groundwater Exposure, Site OT-1 l/OU-2, Residual Pesticide Disposal Area
Geraghty & Miller 26
2-15 Equations and Sample Calculations for Soil Exposure,
Residual Pesticide Disposal Area, Geraghty & Miller 26
2-16 Equations and Sample Calculations for Wading Exposure at
Site OT-1 l/OU-2, Residual Pesticide Disposal Area, Geraghty & Miller 26
2-17 Cancer Slope Factors, Tumor Sites and USEPA Cancer Classifications
for Chemicals of Potential Concern, Site OT-1 l/OU-2, Residual Pesticide
Disposal Area, Geraghty & Miller. 27
2-18 Reference Doses for Chemicals of Potential Concern, Site OT-1 l/OU-2,
Residual Pesticide Disposal Area, Geraghty & Miller 27
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LIST OF TABLES
(continued)
Table Follows
No. Title Page
2-19 Risk-Based Remedial Goal Options for Soil Based on Hypothetical Future
Adult Resident Exposure, Site OT-1 l/OU-2, Residual Pesticide Disposal
Area,Geraghty & Miller 31
2-20 Risk-Based Remedial Goal Options for Soil Based on Hypothetical Future .
Child Resident Exposure, Site OT-1 l/OU-2, Residual Pesticide Disposal
Area,Geraghty & Miller 31
2-21 Comparative Analysis of Final Alternatives for Site OT-1 l/OU-2,
Residual Pesticide Disposal Area, Montgomery Watson 36
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LIST OF FIGURES
Figure _. Follows
No. Title Page
1-1 Location of Homestead Air Reserve Base 1
1-2 Location Map Site OT-ll/OU-2 Residual Pesticide Disposal Area. 2
1-3 Site Map OT-ll/OU-2 2
2-1 Sampling Locations at the Residual Pesticide Disposal Area. 14
2-2 Volatile Organic Compound Concentrations Detected in Soil Samples
Collected During 1993 Investigation 15
2-3 Total Polynuclear Aromatic Hydrocarbon Concentrations Detected in
Soil Samples Collected During the 1993 Investigation 16
2-4 Organochlorine Pesticide Concentrations Detected in Soil Samples
Collected During the 1984, 1988, 1991, and 1993 Investigations 17
2-5 Lead Concentrations Detected in Soil Samples Collected During
the 1993 Investigation 18
2-6 Total Polynuclear Aromatic Hydrocarbon Concentrations Detected in
Groundwater Samples Collected During the 1993 Investigation 19
2-7 Total Polynuclear Aromatic Hydrocarbon Concentrations Detected in
Sediment Samples Collected During the 1991 and 1993 Investigations 20
2-8 Pesticide Concentrations Detected in Sediment Samples Collected
During the 1991 and 1993 Investigations .' 20
2-9 Metal Concentrations Detected in Sediment Samples Collected During the
1991 and 1993 Investigations 20
2-10 Metal Concentrations Detected in Surface Water Samples Collected During
the 1991 and 1993 Investigations 22
2-11 Area of Concern for Site OT-ll/OU-2 33
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DECISION SUMMARY
FOR THE
RECORD OF DECISION FOR OPERABLE UNIT NO. 2
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 the Outfall 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 a 3 mile radius of Homestead ARB, over 4,000 area residents 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
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1
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o
HENDRY COUNTY
I 1
MONROE COUNTY I
PALM BEACH COUNTY
BOCA RATON*/
BROWARD COUNTY
FORT*/
LAUDERDALE
' 1 T -I
DADE COUNTY
I
PERRINEy BISCAYNE
' ( BAY
HOMESTEAD HOMESTEAD
EVERGLADES [_
NATIONAL '
PARK
10 Ml
APPROX. SCAL£
20 Mi
HOMESTEAD AIR RESERVE BASE
HOMESTEAD, FLORIDA
LOCATION OF
HOMESTEAD AIR RESERVE BASE
FIGURE 1-1
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under SAC until July 1968, when it was changed to the Tactical Air Command (TAG) and
the 4531st Tactical Fightenving 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 Reserve 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 oversight by Dade County.
1.1 OPERABLE UNIT NO. 2 DESCRIPTION
Operable Unit 2 (OU-2)/Site OT-11 includes approximately 20 acres and is located in the
west-central portion of the base (Figure 1-2). The site is bordered by the Boundary Canal to
the west and the ordnance storage area to the south (Figure 1-3). Taxiway B lies
approximately 600 feet to the east The site is transected by a drainage ditch which typically
contains water to a depth of a few feet. The ditch flows east to west and is interconnected
with the Boundary Canal. A storage area, roughly 1 acre in size, is located on the east side of
the access road which forms the eastern site boundary. The storage area is maintained by the
Air Force Reserve unit and contains their supplies. The portion of the base where Site OT-
1 l/OU-2 is located has restricted access, limited to only base personnel with specific duties
in this area. There are no public roadways that lead past Site OT-1 l/OU-2. Therefore,
incidental or casual exposure is not likely at this site. Under present conditions, access to the
site would be associated with base workers performing duties that might require site access,
such as cutting the grass. Site OT-1 l/OU-2 is in the area of the base that will be retained by
the Air Force as the 482nd Air Reserve Unit, and the runway will continue to be active. This_.
. land use ensures continued limited access to the site and makes residential development at
the site highly unlikelyT" "
1
The site currently consists of an area characterized by weeds, grasses, trees, and bushes. The
land is undeveloped and is used primarily for storage of dirt/fill material. During the 1991
field investigation (G&M, 1991), three mounds of dirt/fill material (overgrown with large
weeds and trees) were present on the site, and were separated by roads. A more recent
observation of the site (September 1994) indicated that Site OT-1 l/OU-2 was heavily
vegetated, and under heavy rainfall conditions, no surface-water runoff to the drainage ditch
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^^1
HOMESTEAD _^\ \
AIR RESERVE ^%^\
BASE ^3
INSTALLATION BOUNDARY
1000*
APPROX. SCALE
2000"
LEGgMP
BOUNDARY CANAL
LOCATION AND DESIGNATION
OF STUDY AREA
HOMESTEAD AIR RESERVE BASE
HOMESTEAD, FLORIDA
LOCATION MAP
SITEOT-11/OU-2
RESIDUAL PESTICIDE DISPOSAL AREA
FIGURE 1-2
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A "7^ +0. _^ "" _^ <*. X^
-Approximate Location of_Disposal Araa. -
0 1OO 20O
SCALE IN FEET
U.S. ARMY CORPS OF ENGINEERS
HOMESTEAD ARB
SfTE MAP
OT-11/OU-2
FIGURE 1-3
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or the Boundary Canal was observed. The drainage ditch does receive runoff during rainfall
events from pavement in the area.
1.2 REGIONAL LAND USE
The area adjacent to Homestead ARB, including Site OT-ll/OU-2, 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 ARB; 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-2/Site OT-11 is
located in a portion of the Base scheduled to be retained by the Air Force. Due to its
proximity to Taxiway B, development of the site is not likely in the foreseeable future. The
groundwater at the site is not suitable for potable use due to the site's proximity to the
saltwater front, as defined by water containing at least 1,000 milligrams per liter (mg/1)
chloride.
1.3 REGIONAL SURFACE HYDROLOGY
k
Surface hydrology at Homestead ARB, including Site OT-ll/OU-2 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 unconfined aquifer.
Natural drainage is limited because the water table occurs at or near land surface. The
construction of numerous drainage canals on Homestead ARB has improved surface water
drainage and lowered the water table in some areas. Rainfall runoff from within Homestead
ARB boundaries is drained via diversion canals to the Boundary Canal.
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A drainage divide occurs within the Homestead ARB 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 enters the Outfall 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.
13.1 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 Florida Aquifer.
Biscayne Aquifer. The Biscayne Aquifer at Homestead ARB consists of the Miami Oolite,
the 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 hi 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), 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.
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 known to have natural concentrations of target analyte
list (TAL) metals. These metals include, in descending order by concentration; calcium,
aluminum, iron, magnesium, sodium, and potassium. The other TAL metals occur in trace
concentrations, less than 50 milligrams per kilogram (mg/kg). 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). 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. The
conceptual model that shallow groundwater is discharging to ditches provided sufficient
detail to arrive at the remedial decision for Site OT-1 l/OU-2.
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2.0 HISTORY AND ENFORCEMENT ACTIVITIES
2.1 OU-2/SITE OT-11 HISTORY
2.1.1 Past Site Usage
From 1977 to 1982, Site OT-ll/OU-2 was used for the disposal of excess pesticides or
pesticide rinsate, along with pesticide rinsates from equipment cleaning. These diluted
materials were disposed by spraying or dumping them over an approximately 1 acre area
shown on Figure 1-3, and then applying chlorine bleach and ammonia to accelerate the
decomposition of the pesticide compounds. In principle, long-term exposure to ultraviolet
light and soil microorganisms was expected to break down the pesticides and reduce the risk
of contamination.
The storage, use, and disposal of pesticides at Homestead ARB has historically been the
responsibility of the Entomology Shop. Insecticides have been used heavily for many years.
The use of herbicides increased in the late 1970s, when control of the materials- was
transferred from the Buildings and Grounds Department to the Entomology Shop. Some of
the pesticides known to have been used at Homestead ARB are listed in Table 2-1.
Waste pesticides are currently disposed of through the Defense Reutilization and Marketing
Office (DRMO). Prior to 1977, when pesticide disposal began at Site OT-1 l/OU-2, pesticide
rinsate materials were routinely discharged into the base sewage treatment plant. Empty
drums and containers have been disposed of in an approved off-base facility since 1955;
however, since 1976, the containers have been triple-rinsed prior to disposal, in accordance
with standard regulatory disposal practices.
The northern area of the site served as an asphalt and rubble storage area on an intermittent
basis. Asphalt debris collected from around the base was occasionally stored on Site OT-
1 l/OU-2. The asphalt piles were often moved around during site maintenance but were
generally located in the northern portion of the site. An asphalt pile was last reported to be
near the eastern boundary of the site. The pile was approximately 50 feet long, 6 feet high,
and 15 feet wide. The use of this site as an asphalt staging area has been discontinued and
access restrictions have been implemented.
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TABLE 2-1
PESTICIDES STORED AT HOMESTEAD ARB
Vaponite 2EC
Wasp Freeze
Ficam W (bendiocarb)
malathion 95%
Cynthion 57%
baygon strips
baygon 1.5%
Dibrom (85% Naled)
Dursban Granules 0.5% (chlopyrifos)
Dursban 4E
Inspector PT 565
Knox-Out 2FM (Diazinon)
baygon bait
Precor 5E
Talon-G
Baytex
d-Phenothrin (spray cans)
Nemacur
Seven (carbaryl)
Keithane MF
Dowfume MC-2 (methyl bromide)
Phostoxin (aluminum phosphide)
chloropicrin
SA-77, Cide Kick
Nalco-Trol
Dal-e-rad
Velpar
Hyvar X (bromacil)
diquat
Aquazine (simazine)
Balan
Banvel 720
Pramitol 5PS
paraquat
Eptam 7-E
Round-Up (glyphosphate)
Kannex (diuron)
AATREX
Promitol 25e
Asulox
Dowpon (dalapon)
Dithane M-45
Fungo 50 (methyl thiophanate)
Tersan 1991 (benomyl)
Note: Capitalization of the first letter indicates that the name is a registered trademark.
Source: IRP Phase I - Records Search (Engineering Science, 1983)
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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, the US EPA, 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 RI/FS requirements for Site OT-1 l/OU-2 and selects a remedy for
Operable Unit No. 2.
As part of the RI/FS process, Homestead ARB has been actively involved in the Installation
Restoration Program (IRP). From 1983 to 1992, 27 Potential Sources of Contamination
(PSCs) were identified at Homestead ARB. Ten sites have been investigated in the
Preliminary Assessment/Site Investigation (PA/SI) stage of CERCLA, with five sites
warranting no further investigation and five sites requiring further investigation. One of the
PSCs sites has been closed under the Resource Conservation and Recovery Act (RCRA)
guidelines, and seven sites were investigated under the FDEP petroleum contaminated sites
-------
criteria (Florida Administrative Code 62-770). Additionally, a RCRA Facility Investigation
(RFT) has been conducted to evaluate numerous solid waste management units (SWMUs)
identified during the RCRA Facility Assessment (RFA). A cleanup effort was initiated after
Hurricane Andrew to prepare the base for realignment. Additional PSCs have been identified
subsequent to 1992 as a result of investigations and/or remediation of the base. The
following PSCs are currently in various stages of reporting under the CERCLA RI/FS
guidelines:
Operable
PSC Name Unit No.
Fire Protection Training Area 2 1
Residual Pesticide Disposal Area 2
Oil Leakage Behind the Motor Pool 4
Electroplating Waste Disposal Area 5
Aircraft Washrack Area 6
Entomology Storage Area 7
Fire Protection Training Area 3 8
Boundary Canal 9
Landfill LF-12 10
Sewage Treatment Plant 11
Entomology Shop 12
Landfill SS-22 13
Drum Storage Area 14
Hazardous Storage Bldg. 15
Missile Site 16
Hanger 793 17
Construction Debris Landfill 18
Bldg. 208 19
Bldg. 618 Parking Lot 20
#32, Bldg. 619 Parking Lot 21
Bldg. 761/764 22
Bldg. 814 25
Bldg. 745 26
Bldg. 268 &268A 27
Bldg. 750 28
Bldg. 760 29
Operable Unit No. 3 PCB Spill, C.E. Storage Compound has been closed out with a No
Further Action Record of Decision (ROD) in June 1994. Operable Units 1, 4, and 6 have
been completed through the ROD stage, requiring various levels of remedial action/remedial
design. Two solid waste management units, OU-23 and OU-24, have been closed out while
three areas of concern, (AOC-1, AOC-3, and AOC-5) are in the preliminary assessment
phase of investigations.
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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 ARB 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, and were recommended for additional monitoring. The remaining
five sites, one of which was the Residual Pesticide Disposal Area, were determined to have a
low potential for environmental contamination.
According to the IRP Phase I Report, although the wastes applied at the Residual Pesticide
Disposal Site were not applied in a concentrated form on a localized area, the extremely
permeable nature of the surface soils and underlying rock in the area made the site a potential
source of groundwater contamination. However, a HARM score of 58 was received by Site
OT-ll/OU-2 (then Site P-3), which was described as "low" due to the waste's moderate
hazard ranking. A No Further Action recommendation was made for Site OT-1 l/OU-2 in the
Phase Ireport
2.3.2 IRP Phase U - Confirmation/Quantification
An IRP Phase n study was performed by Science Applications International Corporation
(SAIC), and was reported on in March 1986 (SAIC, 1986). The objectives of Phase U 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 El 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
Residual Pesticide Disposal Area was included in this investigation.
Six soil samples were collected at the Residual Pesticide Disposal Site and analyzed for
pesticides. Five of the six samples were found to contain organochlorine pesticides (Table 2-
2). These detections of organochorine pesticides were all at concentrations below the State
of Florida Health-Based Soil Target Levels. The one sample (SL-13) that did not contain any
pesticides was collected from outside of the disposal area. The pesticides detected were
aldrin, 4,4'-DDD, 4,4'-DDT, dieldrin, and methoxychlor. These compounds were identified
as having a high affinity for soil but an extremely low solubility in water. The compounds
were also described as persistent, degrading very slowly in soils, and persisting almost
indefinitely if they enter groundwater.
During the Phase n investigation, Entomology Shop personnel indicated that residual
pesticide rinsates were not only sprayed on the site, as described in the Phase I report, but
were also poured on the ground. Therefore, the possibility that the more mobile compounds
may have entered the groundwater was considered. Additional concerns relative to the
groundwater quality were introduced, due to the thin soil layer and shallow water table in the
area. The recommendations for additional investigations at this site included the following:
(1) install one monitoring well and collect groundwater samples for analysis of. priority
pollutant pesticides to determine if groundwater has been contaminated at the site; and (2)
collect ten soil samples for pesticide analysis, to delineate the extent of contaminant
migration.
2.3.3 IRP Phase HI Technology Base Development
The IRP Phase in is a research phase and involves technology development for an
assessment of environmental impacts. There have been no Phase HI tasks conducted at the
site 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
10
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Page 1 of 1
TABLE 2-2
ANALYTICAL RESULTS OF PHASE II SOIL SAMPLES COLLECTED IN 1986 AT SITE OT-11/OU-2
RESIDUAL PESTICIDE DISPOSAL AREA
Homestead Air Reserve Base, Florida
LOCATION
SL-9
SL-10
SL-11
SL-12
ANALYTE
EXPLANATION:
1/ Replicate sample.
Source: Geraghty & Miller. Inc. (G&M Project No. TF430.01)
SL-13
SL-14
PESTICIDES (ug/kg)
AMrtn
DDD
DDT
Dleldrin
Endrln
Heptachtor
Heptachlor Expoxkto
Undane
Methoxychtor
Toxaphene
Dlazlnon
Malathton
Parathlon
2.4-D
2.4.5-T
2.4.5-TP (sllvex)
Sevtn
<20
<20
90
<20
<20
<20
<20
<10
<20
<10
<20
<100
<20
<60
<60
<60
<1000
<20
BOM) If
670/620
<20
<20
<20
<20
<10
90/120
<10
<20
<100
<20
<60
<60
<60
<1000
<20
<20
260
40
<20
<20
<20
<10
<200
<10
<20
<100
<20
<60
<60
<60
<1000
70
<20
370
30
<20
<20
<20
<10
90
<10
<20
<100
<20
<60
<60
<60
<1000
<20
<20
<20
<20
<20
<20
<20
<10
<200
<10
<20
<100
<20
<60
<60
<60
<1000
<20
<20
30
<20
<20
<20
<20
<10
<200
<10
<20
<100
<20
<60
<60
<60
<1000
4/29/96 10:30 AM
TF430\P3-RrYTABLE 2-2
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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
is then described in sufficient detail to serve as a baseline document for initiation of Phase
IV-B.
An IRP Phase IV-A investigation was performed at Site OT-1 l/OU-2 by Geraghty & Miller
in 1988. The results of this investigation are included in the report entitled "Draft Remedial
Investigation Report for the Building 207 Underground Storage Tank Area, Residual
Pesticide Disposal Area, and the Electroplating Waste Disposal Area, Homestead Air Force
Base, Florida".
Six soil borings were drilled to depths of approximately eight feet (ft) below land surface
(bis). A soil sample was collected from the 0 to 2 ft bis depth interval in each soil boring and
analyzed for organochlorine pesticides and chlorinated herbicides. Organochlorine pesticides
were detected in three of the six samples collected (Table 2-3). These detections of
organochorine pesticides were all at concentrations below the State of Florida Health-Based
Soil Target Levels. Four organochlorine pesticides were detected: 4,4'-DDE, 4,4'-DDT,
alpha-chlordane, and gamma-chlordane. No chlorinated herbicides were detected in any of
the samples. The concentrations of organochlorine pesticides detected in soil samples during
the 1988 investigation were an order of magnitude lower than those detected during the
Phase n investigation.
Groundwater samples were also collected during the Phase IV-A investigation. Groundwater
samples were collected from each of the six soil borings, with the exception of boring B-3
which caved in before a groundwater sample could be collected. The groundwater samples
were also analyzed for organochlorine pesticides and chlorinated herbicides. None of the
constituents analyzed for were detected in any of the samples (Table 2-4).
The Draft RI Report concluded that no organochlorine pesticides or chlorinated herbicides
were detected in groundwater samples, and no chlorinated herbicides were detected in Phase
II or Phase IV-A soil samples. The only contaminants detected were organochlorine
pesticides in Phase n and Phase IV-A soil samples at concentrations below the State of
Florida Health-Based Soil Target Levels. The lateral and vertical extent of contaminants
were delineated over most of the area, with the vertical extent considered to be at the
groundwater table at a depth of approximately 4 ft. The risk assessment utilized the highest
"hot spot" concentrations which makes the risk conservatively high, the results of which
11
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Page 1 of 1
TABLE 2-3
ANALYTICAL RESULTS OF PHASE IV SOIL SAMPLES COLLECTED IN 1988 AT SITE OT-11/OU-2
RESIDUAL PESTICIDE DISPOSAL AREA
Homestead Air Reserve Base, Florida
CONSTITUENTS 1/
LOCATION
B-1
B-2
B-3
B-4
B-5
B-6
ORGANOCHLORINE PESTICIDES (ug/kg)
4.4'-DDE
4.4--DDT
Alpha-cNordane
Gamma-chJoidane
CHLORINATED HERBICIDES (ug/kg)
< 14 <
< 14 <
< 71
< 71
BDL 2J
13
13
41
50
BDL
<
<
J <
J <
14
14
70
70
BDL
< 13
50
8
21
BDL
<
J
J
57
14
14
25
BDL
<
<
J <
J <
13
13
66
66
BDL
EXPLANATION:
I/ Constituents not detected In any samples are not shown.
2J Below Instrument Detection Limit.
J Value Is between level of quantitatton and Instrument detection limit.
Source: Geraghty & Miner, Inc. (G&M Project No. TF430.01)
4/29/96 10:31 AM
TF430\P3-RI\TABLE 2-3
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Page 1 o» i
TABLE 2-4
ANALYTICAL RESULTS OF PHASE IV GROUND-WATER SAMPLES COLLECTED IN 1888 AT SITE OT-11/OU-2
RESIDUAL PESTICIDE DISPOSAL AREA
Homestead Air Reserve Base, Florida
LOCATION B-1 B-2 B-3 B-4 B-5 B-6
CONSTITUENTS 1/
ORQANOCHLORINE PESTICIDES (ug/kfl) BDL2/ BDL BDL BDL BDL BDL
CHLORINATED HERBICIDES (ug/kg) BDL BDL BDL BDL BDL BDL
EXPLANATION:
I/ Constituents not detected In any samples are not shown.
2J Below Instrument Detection Unit.
Source: Oeraghty & Miller. Inc. (G&M Project No. TF430.01)
4/29/96 1^^M TF430\P3-RI\TABLE 2-4
-------
indicated that the site presented minimal potential hazards to public health or the
environment; and no further action at the site was recommended. No Phase IV-B tasks have
been performed for this site.
2.3.5 1991 Remedial Investigation of Site OT-1 l/OU-2
In 1991, a remedial investigation (RI) was conducted at Site OT-1 l/OU-2 by G&M to
evaluate the current soil, surface water, and sediment quality with respect to the USEPA
Target Compound List (TCL) and Target Analyte List (TAL) for VOCs, BNAs, pesticides,
and metals. The 1991 RI included the collection of 19 surficial soil samples (0 to 1 foot
below original land surface) and six surface water and sediment samples from the drainage
ditches around the site. The 19 soil samples were collected around the central and southern
rubble piles to investigate potential dumping of pesticide rinsates and runoff from the
mounds.
2.3.6 1993 Remedial Investigation of Site OT-ll/OU-2
In 1993, G&M performed additional RI assessment activities to further evaluate the soil,
groundwater, surface water, and sediment quality with respect to the USEPA TCL/TAL for
VOCs, BNAs, organochlorine (OC) pesticides/PCBs, and metals, utilizing EPA Contract
Laboratory Program (CLP) protocols. These RI activities were conducted to fill data gaps
from previous field investigations as well as evaluate any impacts as a result of Hurricane
Andrew. Eighteen surficial soil samples (0-1 foot below original land surface) were
collected from an expanded area around Site OT-1 l/OU-2, two groundwater samples were
collected from the site's existing monitoring wells, and four surface water and sediment
samples were collected from the drainage ditch which surrounds the site.
2.4 COMMUNITY PARTICIPATION fflSTOR Y
The Remedial .Investigation, Baseline Risk Assessment, Feasibility Study Reports, and the
Proposed Plan (PP) for Homestead ARB Site OT-1 l/OU-2 were released to the public in July
of 1994 and September of 1995, 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.
12
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The public comment period was held from September 18, 1995 to November 3, 1995 as part
of the community relations plan for Operable Unit No. 2. Additionally, a public meeting was
held on Monday, September 18, 1995 at 7:00 PM at South Dade High School. A public
notice was published on September 6, 1995 in the South Dade News Leader and on
September 7, 1995 in the Miami Herald. At this meeting, the USAF, in coordination with
USEPA Region IV, FDEP, and Dade County Environmental Resource Management
(DERM), discuss the RI results, the Baseline Risk Assessment, the Feasibility Study, and the
Proposed Plan. A response to the comments received during this period is included in the
Responsiveness Summary, which is part of this ROD.
This record of decision document presents the selected remedial action for OU-2 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.
SCOPE AND ROLE OF RESPONSIVE 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 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-2 as the Residual Pesticide Disposal Area. 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 contamination identified at OU-2. The purpose of this
response is to remove the soil contamination from the site, thereby eliminating the current
and potential future exposure pathways and the potential for migration to groundwater and
the Boundary Canal. This alternative offers a permanent solution for the site because the
contaminated soils are removed, eliminating risk to base personnel and potential future
residents.
2.6 SUMMARY OF SITE CHARACTERISTICS
From 1977 to 1982, Site OT-11 was used for the disposal of excess or pesticide rinsate, along
with pesticide rinsates from equipment cleaning. The materials were disposed by spraying or
13
-------
dumping and then applying chlorine bleach and ammonia to accelerate the decomposition of
the pesticide compounds. In principle, long-term exposure to ultraviolet light and soil
microorganisms was expected to break down the pesticides and reduce the risk of
contamination.
The storage, use, and disposal of pesticides at Homestead ARB has historically been the
responsibility of the Entomology Shop. Insecticides have been used heavily for many years.
The use of herbicides increased in the late 1970s, when control of the materials was
transferred from the Buildings and Grounds Department to the Entomology Shop. Waste
pesticides are currently disposed of through the Defense Reutilization and Marketing Office
(DRMO).
The northern area of the site served as an asphalt and rubble storage area on an intermittent
basis. Asphalt debris collected from around the base was occasionally stored on Site OT-
1 l/OU-2. The asphalt piles were often moved around during site maintenance but were
generally located in the northern portion of the site. An asphalt pile was last reported to be
near the eastern boundary of the site. The pile was approximately 50 feet long, 6 feet high,
and 15 feet wide. The use of this site as an asphalt staging area has been discontinued and
access restrictions have been implemented.
The following subsections summarize the nature and extent of the contamination identified at
Site OT-1 l/OU-2 during investigations conducted from 1984 through 1993. The
investigations in 1991 and 1993 were conducted in accordance with the approved Facility
Remedial Investigation Work Plan (G&M), 1991.
2.6.1 Nature and Extent of Con lamination
Four field investigations have been performed at Site OT-1 l/OU-2. They were performed in
1984, 1988, 1991, and 1993. Soil samples were collected during all four investigations.
Groundwater samples were collected during the 1988 and 1993 investigations. Sediments
and surface water samples were collected in 1991 and 1993. Figure 2-1 summarizes the
various sampling locations. This section presents the results of the investigations for the
affected media. All reported data meet data quality objectives as stated in the remedial
investigation report (G&M, 1994a).
14
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Storage Area
Ajphatt Parking Lot
P3-SVV-0006
P3-SO-0010
P3-SW-OO10
PJ-SW-OOOa
-0017
P3-SW-0012
P3-SW-0001
-P>SD-0001
l
A Sol Boring Locallon-Ocslgnatlon Denotes Pt*s»
SL-tO (1964 IRP Ptvu* II)
P3-SL-0007 to P3-SL-0026 (1991 CERCLA Phas* I)
P3-SL-0027 to P3-SL-003S (1993 CERCLA PtWM 10
S*dbMrt Sample Locttlon
OMlgnallon D«nol«» PhAM:
PJ-SD-0001 to P3-SO-0000 (1991 CERCLA PtXM I)
P3-SD-0010 lo P3-SO-0013 (1993 CERCLA PMs* II)
5urt«o» W«*r Sample Loatton
P»ilgn«[lon O*no<*t Phaa«:
P3-SW-O001 lo P3-SW-0009 (1991 CERCLA PMM I)
P3-SW-0010 to P3-SW-0013 (1993 CERCLA Phu« II)
9 MonlonngWMLoeulon
OMP Monitoring W«l Loottan
SR* Boundvy f J Open Gnwund
Canal
Ftow CMr»cIk)n
U.S. ARMY CORPS OF ENGINEERS
HOMESTEAD ARB
SAMPLING LOCATIONS AT THE
RESIDUAL PESTICIDE DISPOSAL AREA
SITE OT-11/OU-2
100 200
SCALE IN FEET
-------
2.6.1.1 Soil Contamination
Six shallow soil/weathered-rock samples were collected at Site OT-1 l/OU-2 in 1984 during
the IRP Phase n investigation and analyzed for chlorinated pesticides. Another six shallow
soil/weathered-rock samples (0 to 2 feet below ground surface [bgs]) were collected at Site
OT-1 l/OU-2 in 1988 during the IRP Phase IV investigation. These samples were analyzed
for chlorinated pesticides and chlorinated herbicides. A total of 19 shallow soil/weathered-
rock samples (0 to 1 foot bgs) were collected from an expanded area around Site OT-11/OU-
2 in 1991. These samples were taken around the central and southern rubble piles and were
analyzed for chlorinated pesticides. A total of 18 shallow soil/weathered-rock samples were
collected from the 0-1 and 1-2 ft bgs interval from nine soil boring locations at Site OT-
1 l/OU-2 in 1993. These 18 samples were analyzed for target compound list (TCL) volatile
organic compounds (VOCs), TCL base/neutral-acid extractable organic compounds (BNAs),
chlorinated pesticides, and target analyte list (TAL) metals.
Detailed concentrations of analytes for the 1991 and 1993 field investigations are
summarized in Tables 2-5 and 2-6. Results of the soil analyses are discussed below for each
analytical group (i.e., VOCs, BNAs, etc.).
Volatile Organic Compounds. VOCs were analyzed only in the soil/weathered-rock
samples collected during the 1993 field investigation. Analytical results are presented in
Table 2-6.
Acetone was the only VOC detected above the practical quantitation limit (PQL) (95%
confidence limit that the concentration reported is the actual concentration) in surficial and
subsurface-soil/weathered-rock samples, in concentrations ranging from 67 ug/kg dry weight
(dw> to 29,000 ug/kg dw, and was recognized as a laboratory artifact. Additionally, acetone
concentrations detected may be the result of the oxidation of isopropyl alcohol, which was
used during decontamination procedures. Seven other VOCs were detected above the
method detection limit but below the PQL, including 1,1-dichloroethene, carbon disulfide,
chloroform, 2-butanone, bromodichloromethane, dibromochloromethane, and bromoform as
shown on Figure 2-2. Chloroform and 2-butanone are common laboratory artifacts.
Potential sources for bromoform, chloroform, bromodichloromethane, and
dibromochloromethane could be natural or from treated water.
15
-------
TAB 5
CONSTITUENTS DETECTED IN SOIL/WEATHERED ROCK SAMPLES COLLECTED IN 1991 AT SITE OT-ll/OU-2
RESIDUAL PESTICIDE DISPOSAL AREA
HOMESTEAD AIR RESERVE BASE, FLORIDA
Sampk Identification
Analyte Sampling Date
ORGANOCHLORINE PESTICIDES Gig/k| dw)
44'-DDD
44--DDE
Dieldrin
Sampk IdenUflcalioa
Analyte Sampling Dale
ORGANOCHLORINE PESTICIDES (|ig/kg dw)
44'-DDD
44'-ODB
Dieldrin
Endosulfan II
Sample Identification
Analyle Sampling Date
ORGANOCHLORINE PESTICIDES (ug/kg dw)
44' ODD
44'- DDE
Dieldrin
P3-SL-0007 P3-SL-0008 P3-SL4009 P3-SL-0010 PJ-SL-0012
7/2491 7/26V91 7/2691 7/26/91 7/2491
< 5.0 < 5.1 < 4.8 < 4.5 9.6 1»
< 5.0 1.2 J < 4.8 < 4.5 < 24
< 5.0 < 5.1 < 4.8 < 4.5 10 J>
P3-SL-0016 P3-SL-0017 P3-SL-0018 P3-S.L-0019 PJ-SL-0020
7125191 7/2V91 7/2S91 7125191 7/25/91
< 4.7 < 4.7 < 5.1 < 4.5 < 4.7
3.1 J < 4.7 < 5.1 < 4.5 < 4.7
< 4.7 < 4.7 < 5.1 < 4.5 < 4.7
< 12 < 12 < 13 < 11 < 12
P3-SL-0025 P3-SL-0026
7/2V91 in/6191
< 4.7 < 6.3
< 4.7 < 6.3
< 4.7 < 6.3
i Result has been classified as qualitative due to error(f) in associated quality control analyses.
b Duplicate analysis for P3-SL-001 3.
lig/kg dw micrognras per kilogram dry weight.
< Aiulyte was not delected. The value* given are equal to the practical quantitation limits requested in the Rl Work Plan and may
dilution factors. '
I Value is greater than instrument detection limit but leu than practical quantitation limit.
P3-SL-0013 PIVSL-MIJ* P3-SL-0014 P3-SL4015
7/2591 7/2591 7/2591 7/2591
< 4.7 < 5.4 < 4.6 < 4.8
< 4.7 1.4 Ji < 4.6 < 4.8
< 4.7 < 5.4 < 4.6 < 4.8
P9-SL4021 P3-SL-0022 P3-SL-0023 P3-SL-0024
7/2591 7/2591 7/2591 7/2591
< 22 < 4.6 < 5.8 < 5.0
< 22 < 4.6 < 5.8 <: 5.0
< 22 < 4.6 < 5.8 < 5.0
19 J» < 12 < 15 < 13
vary among samples due to differences in water content, mass analysed, and
From: Ceraghiy i
I. I99la
-------
TKITKD IN souywKATiiEKED HOCK SAMPLES COI.LECTKD IN iwj
AT sn>: OT i i/ou-2, MKSIUUAL PESTICIDE DISPOSAL AHCA
IIOMKSTKAU AIK WuSKHVE BASE. FLORIDA
lH«te I of 5)
P«ramc(tr Borinfl.D. PJ-SKW27-I P3-SL-O027-2 PJ-SL-OOZS-l PJ-SL-002»-J P3-SL-W2M PJ-SL-«U»-2 PML-OOJt-l
Sampllot lnltr»*J 0-1 It bp 1-2 nbp 0-lftbgs IJftbp »-l fl bp l-2flbgl 9-lftbp
VuUule Organic Compounds
Uig/Vgdw)
Mtlhyleoe Chloride < 1.600 < U (220) UJ. < 12 (320)
Actions [ 3,100 | ( 1(50 | J | S.IOO | J« < 12 UJ | 19,000
Outwo Disulfidt < LoOO < n < 1.500 UJ. < 12 < TSJb~
I.l-Dichloiuelhcne 1.600 < 14 < 1.300 UJ. < 12 < 1.600
I.l-Dichluroetluae 1.600 < 14 < 1.500 UJ. < 12 < 1.600
Chloroform 1.600 < 14 < 1.500 UJ- < 12 < 1.600
2 Buunone (MEK) (1.300) U < 14 UJ | 1,300 | J« < 12 UJ | ' j.MQ
BromcKlichlOfomelhuw 1.600 < 14 < 1400 UJ. < 12 < t.600
Oibromochloromeihuc 1.600 < 14 < 1.500 UJ. < 12 < 1.600
Bromoform < 1.600 < 14 < 1400 UJ. < 12 < 1.600
Chlurobcoicoe < 1.600 (5) U < 1.500 UJ. (4) U < 1.600
Buc/Nculral and Acid EilrkcUblc
Compouodi (ji|/kt dw)
N.phlhlltDC (38) < 460 < 390 < 390 < 410
2-Mclhyloiphlhileoe (24) < 460 < 390 < 390 < 410
Aceoaphthyleae < 420 < 460 < 390 < 390 < 410
Acco&Dhtftcoc 62
Dibtojofuun oT
Ruorent T9JT"
N-Njuotodipheaylamioe/ < 420
OiphcnylamiDC
< 460 n
< 460 "~O
< 460 (6
T < 390 < 4IO
T < 390 < 4IO
T5 < 390 < 410
< 460 < 190 < 390 < 410
pnenioilucoc 1 7^0 1 < Wo \.
Aolhuccoc 1 (190) | < 460 (J
Cubtzolc (»l)
Dt-o-buiylphlhaJiic < 420
Fluonnihcoe 1,100
Pyreoe 900
BurylbeoiylphihiJiic < 420
beaiodJiailmcenc | 580
CIvytcoe | 590
bii(2-EUiylh»yl)phih*l«e < HO"
BeoiotbllluonDtneae 69C
Benio ~i.
do n
J < 460 5
I < «60 g
< 460 < 3
< 460 J
< 460 ~n
< 460 " "t
< 460 ' "J
< < 12 < 1.500
1 ! < 12 UJ | M.OOfl |
UJi < 12 < IJM
Ul. < 12 < 1400
U). < 12 < 1.500
U). < 12
J" J« < 12 UJ
UJ. < 12
UJi < 12 <
UJ. (4) U <
UJ. < 12 <
< 390
< 390
< 390
< 390
< 390
< 390
< .390 <
< 390
< 390
< 390
< 390 <
< 390
< 390
< 390 <
< 390
c 390
(200)
(1.200)
(250)
1400
1400
1400
(390)
(210)
(68)
500
530
560
400
8.900
I.WO
880
400
13,000
400
8.400
7.700
< 390 < 400
(16)
(7)
< 390
< 390
< 390
] < 390
14.000
2.300
10.000
6.300
940
6.200
1
J.
VI
J.
J«
UJ
J
J«
J«
)
1
I | 3.310 | | 3.&M |
< TT9 < TTT
< 2« (29.7) )
12 1 ' j|l '
306.000 H5.0M
9.8
< 5.9
| 2.090 [
(!l.05fl>
2]1
?9.4
4420
1.240
III
n«
J
J
-------
TABU. /-*
CONS'! n UKNTS DKiKTun IN son JWKA niKUJ) BOCK SAMPLES COI.I-KCTKI* IN w.»
A I SI'I'K Of.I I/Oil 1, KKMIHIAI. PKSTirilJK DISPOSAL ARKA
IIOMKSTHAII AIK kKSKHVK BASE. MXJHIDA
(l'»te I of 5)
Parameter Boring LD. P3-SI-M27-I P3-SL.0027.2
Sampling Interval 0-lflbg» 1-2 nogs
Sodium (540) J I 18|$T 1 '
Vanadium | (3.5) | U < IS
inc TT7 J < 56
Atiemc < 2.5 UJ < 2.8
Lead | 79 | < 084
Mercury < 0.06 < 007
OrgaoochloriM PeslkldeWCBs
Hepuchlor epotide < 2.2 < 2.4
4.4'DDK I""?!
4,4'DUT (~~~n
< 4.6
< 4.6
tlpha-Chlordane < 2.2 < 2.4
gtmnu-Cnlofduc < 2.2 < 2.4
PJ-SL.Q028-I PKSL-0018-1 P3.SL-0029-I P3-SL-002«-2 P3-SL-0030-1
0-1 ft bp 1-2 ft b(i 0-1 ft bgi l-2Dbgf 8-lflbgv
(502) j r
7 7 . J
ft s r
339B [
O.bs <
< 2 <
(632) '
1 T J
ri;zq
637.0 |
0.06
2 <
39 <
3.9 <
2 <
2 <
(342)
(0j' '
ii
vft
0.06
2.1
4.1
4.1
2.1
2.1
J (379) J (369)
r* ff fl i ($zi
j 4.7 j jm""
< 2.4 UJ Ti 7 J
[ 5.J" J 86.8
< 0.05 0.39
< 2 UJ < 40
< 2 UJ < 40
< 2 UJ < 20
< 2 Ul < 20
Parameter Boring LD. P3-SL-K30-2 PJ-SL-003I-I
Sampliaf Inlerral 1-2 ft bgt ! ft bg>
VoUIile Organic Compounds
(MtAt «)
Methylene Chloride < 1.600 < II UJ
Acetone | 3,700 | | 1.100 |
C«roon Disulfide < 1.600 < TI UJ
l.l-DicrtloroeUieoe | (23
I.I Dichlotoethine < 1.4
Cnioiolonn | (V
2-Buunooe (MEK) < T!
BiomodichlOforncUiane H5
DibromoclUoromethine J4l
Uiomolorm (18
oy^ < n uj
HT~^ < n UJ
oTH < n UJ
E) < II UJ
0*i < II UJ
j) " < n UJ
5T" < n uj
ChJorobtiuene < TZOO < II UJ
Ban/Neutral aw) Acid E«tracUble
Compouadi (jif/kg d w)
Niphlhileoe (28) < 380
2 MeihyloaphiruJeoe (17) < 380
AceuphUiylene $
Acentphdieoe i3"
Uibeozolurao (4
f-luorcoe (4
N-Niuoudiphcnylimiae/ < 4*5
Uipheoylamioe ____
Phcointlueae 1 4
AnlhiKeoc | (1
Cufauole («
Di-o butylpruhiliie < 4
KluortouVoe | 7
Pyteot | T
Bulylbciuylphlhllilt "7!!
Beou>U>inihnceoc 1 (4
UiryseiK | T
} < 380
S < J80
I) ( . i*^ I
JJ < 38()
D < 380
10 | MOO)
0) | (26)
6) (25)
tO < 380
oH I (JoHi
* U ?,',, U
6} \ (130)
SO j (I5d>
' P3-SL-003I-2 PJ-SL-W3I-I
1-2 ft bg» 0-1 ft bts
< 12 <
< 12 <
< 12 <
< 12 <
< 12 UJ <
< 12 <
< 12 <
< 12 <
(4) U <
< 410 <
410 <
410 <
410 <
410 <
410 <
410
i rno) i
< 410 <
-i5roH
(23y U
-------
CON.STITHKN1N DKIU'I HI IN S<)II/WKATIIKKU> HOCK SAMH.KS COU-KtTKIJ IN IW.I
ATSriKOI--II/OII i.HKSIMIAI.PKSTICIDKIllM'USALAKKA
IIOMK5I KAI> AIM HKStKVK BASE. KLOKIDA
lHigeJo/5)
Parameter Boriof LD. P3-SL-0030-2
Sampliiii Interval 1-2 II bf»
bis(2-Ethxlhe«xl)phthaJiie < 420
Ben20(D)HuonnuieRe 760
Heazo(k)nuariBinene (260)
ben
< 2.3
(437)
< 2.3 UJ
1 «.»30 I
< o.w
Organothlorlnc PeslkMes/PCBt
(ji^kfdw)
Hepuchlor epoude < II UJ < 2
4,4'-DDE < 21 UJ < 3.9
4.4'-DDT < 21 UJ < 3.9
ilphi-Chlotdue < II UJ < 2
|amm»-Chlordanc < II UJ < 2
P3SL-003I-J
1-2 n bgs
< 410
(250)
(94j
(150)
(97)
< "Tiff
| (81)
| T.TM )
5 J
< 12
| ^8g.TO |
< 6.2
1.510 J
| 71. IW ]
1 216 | J
(462)
< 2.5 UJ
| 590
< 0.06
< 2.1
< 4.1
< 4.1
< 2.1
< 21
P3-SL-W3I-1 P3-SU003M P3-SL-0032-2 P3-SL-0033-1
0-inbgf ft-inbgj l-2flbgj 0-IHbgi
< 380 (14)
' fl3B7 (34)
;<9) (M)
(liO) twj
"(95T <
-------
TAUI.ti*
CONSTITUKNTS tiKi>:u ti> IN SOIITWHATHKKKD HOCK SAMPLES COLLKCTKD IN iw
ATSll> OMI/OU 2, KKMIIUAI. PKSTICIliE DISPOSAL ARUA
IIOMKSTKAI) AlK KKSKHVE BASE, FLORIDA
lP«je 4 uf 3)
Parameter Borln(LD. P3-SL-0033-2 P3-SU0034-I U-3-SL-OOJ4-2 P3-SL-OOJ5-1 PJ-SU0035-2
Sampling Interval l-2ftbgs 0-1 ft bgs 1-2 flogs *-inbgi llflbRj
Dibroniuchloromethane < 13 7350) < 63
Biomoforro < 13 < "1.700 < 65
Oilorobenieoe < 13 < 1.700 < 65
Basc/Neutrd and Add EilncLabk
Compounds Oi|/k|dw)
Niphihalenc < 420 < 450 < 430
2-MethylnaphlhaIene < 420 < 450 < 430
Acenaphlhylene < 420 < 450 < 430
Acenapbthene < 420 < 450 < 430
Dibeozofunn < 420 < 450 < 430
Fluorene < 420 < 450 < 430
N-Niirosodiphenylimine/ < 420 < 450 < 430
Oiphenyltmine
Phenaniluene < 420 (13) < 430
Anthracene < 420 < 450 < 430
Carbazole < 420 UJ < 450 UJ < 430
Di-n-buiylpluJulale < 420 < 450 < 430
Fluoramhene < 420 (38) < 430
Pyreoe < 420 (45) < 430
BuiylbeiuylphUulaie (16) U (26) U < 430
Benio(a)anlhracene < 420 < 450 < 430
Chryiene < 420 (25) < 430
bis(2-Elhylheiyl)phlhalaie < 420 < 450 (7) I
Benzo(b)l1uoranJieQe < 420 (40) < 430
BeniodOnuoranthene < 420 (13) < 430
Bcnio(a)pyrene < 420 (20) < 430
lnj£Do(l.2.3.h)inUiiacene < 420 < 450 < 430
Bcnzo((.hj)perylene < 420 < 450 < 430
MeUls (m|/k| dw)
Aluminum 157 | 3". 120 ] 718
Antimony < 12.9 < ITT < 12.9
Barium < 5.1 < 5.5 < 12.9
Cadmium < 1.3 < 1.4 < 1.3
Calcium 337.000 329.000 | Ml 000 |
Chromium 2.8 f j|g "| 4.8
Copper < 6.4 < 6.9 < 6.5
Iron 81.4 J ' J.|
Magnesium (VI?) 7T7I
Manganese 4.6 J J?
WT 1 462
< 12 < 14
< 12 < 14
< 12 < 14
1
(11) < 450
< 400 < 450
Illff < 450
" "TH) " < 450
< THJ < 450
1 (9) | < 450
< VSS < 450
7JS6T" C2)
fJJT"_ < 450
P5) < 450 UJ
< 400 (8) U
f!5J5 UJ < 450
SID (44)
iJSJT' (18)
IJ60) (24)
(240) < 450
< 400 ' < 450
699 810
< 12 < 13.7
< 4.8 < 5.5
MlflflO 345,000
11.2 4.5
< 6.0 < 68
J 1.360 J 454 J
DOT (lOlO) [ 1.370 1 [ (1.260) ]
n~ J 8.7
Silver < 2.6 < J.7 < 2.6
Sodium |' (J7T) 1 <*»») (346)
Vanadium < 1.6 | li.Y) ] [ (17) ]
Zinc < 5.1 < TT < 5T
Arsenic < 2.6 UJ < 2.7 UJ < 2.6 t
Lead < 0.77 1 TJ! I 0.97
Mercury < 0.05 < TJ
06 < 0.06
J 22.2 J 115 J
< 2.4 < 2.7
(*'4) (" (714) |
(ll) < 5.7
'"H.J" < 5.5
JJ < 7.1 UJ < 2.7 UJ
1 '"S'l.o" ] i.J
< B7K < 0.06
OrtMochtorinc PesticideVPCBi
(jitAfdw)
Hepiachlor epoiide
2.2
2.3
2.2
23
-------
TABU,*-*
CONSTITUENTS DETECTED IN SOIL/WEATHERED ROCK SAMPLES COLLECTED IN 19*3
AT SITE OT-ll/OU-X RESIDUAL PESTICIDE DISPOSAL AREA
HOMESTEAD AW RESERVE BASE, FLORIDA
(ftttiot!)
Parameter Boring LD.
Sampling Interval
4,4'-DDE
4.4'-DDT
alpha -Chlordane
ganuna-Chlordane
P3-SL-003J-J
1-2 ft bgs
< 4.2
< 4.2
< 2.2
< 2.2
P3-SL-0034-1
0-1 Hogs
< 4.5
< 4.5
< 2.3
< 2.3
1P3-SL-M34-2 P3-SL-003S-1
l-2flbcs Mftbg*
< 4.3
< 4.3
< 2.2 <
< 2.2
5.2 I
15 1 I
35 I J
P3-SL-0035-2
l-2ftbgt
< 4.5
< 4.3
< 2.3
< 2.3
Notes:
Result from reanalysis of sample.
rnicrograms per kilogram dry weight
milligrams per kilogram dry weight
Aualyte wu not detected M or above the iodicaied coocenlniioo. Values may vary amoa| samples due to difference in water conical, mass analyzed, and dilution factors.
Result is greater than the Instrument detection limit by less than the practical quanlilalion limit.
Positive result has been classified as qualitative.
Analyte was not delected and has been classified as qualitative.
Result has been classified as undetected.
Concentration above average Homestead AFB background concentration (Table 2-7).
From: Geraghiy A Miller. Inc.. I993a
Mg/kgdw
mg/kgdw
<
0
UJ
u
-------
_T"^~- rr^ * -- ^~
0-in. bg» 1-2n
A Sol Bating
::=:= Dnlnags Mch
I Vak* b MtwMn toval of quantlalton
and kutnNTwm d*i«eiion imi
HMvly v*gltat«d Ana
(RubM* Mound)
Not*: Only wa» umplc* eoMdid In 1983 w*ni
anMyz«o lor VOCs.
U.S. ARMY CORPS OF ENGINEERS
HOMESTEAD ARB
VOLATILE ORGANIC COMPOUND
CONCENTRATIONS DETECTED
IN SOIL SAMPLES COLLECTED DURING
1993 INVESTIGATION
SITEOT-11/OU-2
-------
Base/Neutral and Acid Extractable Compounds. BNAs were analyzed only in the
soil/weathered-rock samples collected during the 1993 field investigation. Analytical results
are presented in Table 2-6.
A total of 21 BNAs (mainly polycyclic aromatic hydrocarbons [PAHs]) were detected in the
soil samples from Site OT-ll/OU-2. Benzo(a)pyrene was detected in concentrations
exceeding the State of Florida Health-Based Soil Target Levels in soil samples P3-SL-0027-
1, P3-SL-0028-1, and P3-SL-0030-1. Soil sample P3-SL-0031-1 also had detections of
Benzo(a)anthracene, Benzo(b)fluoranthene, and Dibenzo(a,h)anthracene at concentrations
exceeding the State of Florida Health-Based Soil Target Levels. In the surficial (0 to 1 foot
bgs) soil samples, total PAH concentrations ranged from 141 ug/kg dw (P3-SL-0032-1) to
92,968 ug/kg dw (P3-SL-0030-1) as shown in Figure 2-3. The samples with the highest
concentrations of total PAHs (surficial samples P3-SL-0027-1, P3-SL-0028-1, and P3-SL-
0030-1) were collected from the original land surface at approximately 4 to 5 feet below the
overlying fill material. These concentrations of total PAHs may be the result of the asphalt
debris (a hydrocarbon material which contains PAHs) encountered in the fill material. It is
recommended that asphalt and other construction debris not be stored at this site in the future.
Total PAH concentrations were lower in the subsurface (1 to 2 feet bgs) soil/weathered rock
samples. Total PAH concentrations ranged from below the detection limit (P3-SL-0034-2
and P3-SL-0033-2) to 5,150 ug/kg dw (P3-SL-0030-2). Most of the concentrations detected
were below Florida Administrative Code (FAC) Chapter 62-775 Clean Soil Standard for total
PAHs of 1,000 ug/kg dw. The lower total PAH concentrations detected in die subsurface
soil/rock samples may result from less mixing with the asphalt material from the overlying
fill material.
Generally, concentrations of acenaphthylene, acenaphthene, anthracene, benzo(a)anthracene,
benzo(a)pyrene, benzo(b)fluoranthene, benzo(g,h,i)perylene, benzo(k)fluoranthene,
chrysene, dibenzo(a,h)anthracene, fluoranthene, fluorene, indeno(l,2,3-c,d)pyrene,
naphthalene, methylnapbthalene, phenanthrene, and pyrene detected in the soil/weathered
rock samples were within the range of Homestead ARB background concentrations (Table 2-
7) for surficial soil/weathered rock samples. The PAH concentrations in three samples (P3-
SL-0030-1, P3-SL-0028-1, and P3-SL-0027-1), however, exceeded those average
background concentrations for surficial samples.
Several non-PAH BNA compounds were also detected in the surficial and subsurface
soil/weathered rock samples collected at Site OT-1 l/OU-2. The phthalic acid ester (PAE)
16
-------
P3-SL-0031/B031
FtowdlivcUon
I... 1 Op»n GnuUnd
NoU: Only sol Mmptei eotectod h 1003 WOT
MlyadlorPAH*.
U.S. ARMY CORPS OF ENGINEERS
HOMESTEAD ARB
TOTAL POLYNUCLEAR AROMATIC
HYDROCARBON CONCENTRATIONS DETECTED
IN SOIL SAMPLES COLLECTED DURING
1993 INVESTIGATION
SITE OT-11/OU-2
0 100 200
SCALE IN FEET
-------
TABLE 2-7
BACKGROUND SOIL CONCENTRATIONS
HOMESTEAD AIR RESERVE BASE, FLORIDA
Compound
Average
Carbonate
Composition
Hem (1989)
Homestead ARB
Background
SoiT
0-2 ttbb
Typical Values for
Uncontaminated
Soils'
(mg/kg)
Common Range'
(mg/kg)
Average*
(mg/kg)
Volatile Organic
Compounds (Mg/kg)
Acetone
Chlorobeozeoe
Methylenc Chloride
Total PAHs (jig/kg)
Base/Neutral and Add
Extractabk Organic
Compounds (ug/kg/dw)
Acenaphthene
Benzo(a)anthracene
Benzo(a)pytene
BeazoOOfluoranthene
Benzo0.1
0.12
4.4
8.190
16
45,300
842
0.046
13
2.390
398
13
16
119.2
3.8
4
738.55
ND
67
66
69
44
66
100
79
ND
52.4
ND
84
50
50
49.15
ND
ND
126
2,400
<28-30
1.6
42.9
IO,000
2-KJ0
<0.1-73
10-1.500
<1 -7
0.01-0.1*
10 - 28,000
1 -1.000
<0.3 - 70
-------
butylbenzylphthalate was reported in samples P3-SL-0027-1, P3-SL-0027-2, P3-SL-0028-1,
P3-SL-0028-2, and P3-SL-0029-1 at concentrations ranging from 14 to 36 ug/kg dw (Table
2-6). PAEs are plasticizers used in the production of various plastics. PAEs have become
ubiquitous in the environment because of their general usage, and they also commonly occur
as laboratory contaminants. Other BNA compounds detected include dibenzofuran, N-
nitrosodiphenylamine, carbazole, and DEHP. Most of these reported values were qualified
because the concentrations were less than the PQL (Table 2-6).
Organochlorine Pesticides. Soil samples were analyzed for organochlorine pesticides
during all four soil investigations. From all four of the sampling rounds (49 samples), nine
pesticides were detected in at least one shallow soil/weathered-rock sample. Chlordane,
dieldrin, and methoxychlor were detected in five, three, and two of the 49 samples,
respectively. 4,4'-DDD and 4,4'-DDE were detected in two and seven of the 49 soil samples,
respectively; and 4,4'-DDT was detected (most frequently) in eight of the 49 samples.
Aldrin, endosulfan n, and heptachlor were detected only once. Figure 2-4 summarizes the
concentrations of pesticides detected in the soil samples during the various investigations. In
1984, the highest concentration detected in any sample was 670 ug/kg dw of 4,4'-DDT in
sample SL-10. In 1988, soil sample B-4 (150 feet to the east of SL-10) contained 50 ug/kg
dw of 4,4'-DDT, and sample B-5 contained 57 ug/kg dw of 4,4'-DDE, a DDT degradation
product. The concentrations of organochlorine pesticides detected during the 1988
investigation were an order of magnitude lower than those detected during the 1984
investigation. This may indicate that the greatest pesticide concentrations are located within
the area of the 1984 soil sampling investigation because the degradation half-lives of
pesticides are very long and the lower concentrations detected in 1988 are not likely to
indicate degradation of pesticides.
During the 1991 investigation, low levels of organochlorine pesticides, including 4,4'-DDD,
4,4-DDE, dieldrin, and endosulfan n were reported in four of the 19 samples. However, all
of these reported concentrations were qualified, either because the concentrations were less
than the practical quantitation limit, or due to errors in associated quality control analyses
(Table 2-5). The presence of these pesticides is consistent with other investigations.
During the 1993 investigation, three pesticides, 4,4'-DDE, 4,4'-DDT, and alpha-chlordane,
were detected in three surficial (0 to 1 foot bgs) soil/weathered rock samples (P3-SL-0027-1,
P3-SL-0028-1, and P3-SL-0035-1). 4,4'-DDE was detected in these soil samples at
concentrations of 5.3, 7.1, and 5.2 ug/kg dw, respectively (Table 2-6). Overall, elevated
concentrations of organochlorine pesticides were detected in samples collected from the
17
-------
8-4(1988)
Pesticide
DOT
AJphi Chtordan*
Gamma CMortana
n*
dan*
-
u
-------
northern and central portion of Site OT-ll/OU-2. Pesticide concentrations were typically
higher in the surflcial soil samples (0 to 1 foot bgs) than in the subsurface soil/rock samples
(1 to 2 feet bgs) as illustrated in Figure 2-4.
No chlorinated herbicides were detected in the samples collected during the 1988
investigation; and therefore, the analysis for herbicides was not performed in the subsequent
sampling rounds.
No PCBs were detected in the soil samples at Site OT-1 l/OU-2.
Inorganic Constituents. Soil/rock samples were analyzed for inorganic constituents only
during the 1993 investigation; a total of 17 metals were detected.
Aluminum, calcium, chromium, and iron were detected above the PQL in all soil samples
(Table 2-6). Concentrations of aluminum ranged from 157 mg/kg dw to 13,200 mg/kg dw.
The concentrations of calcium did not vary as greatly but were significantly higher ranging
from 248,000 mg/kg dw to 489,000 mg/kg dw as expected from a sample consisting of
weathered Miami Ofllite. Chromium was detected in every sample at concentrations ranging
from 2.8 mg/kg dw to 39.9 mgVkg dw. Iron concentrations ranged from 81.4 mg/kg dw to
9,120 mg/kg dw. These concentrations are generally within the range of the Homestead
ARB background, with aluminum and chromium concentrations slightly higher than the
upper limit (Table 2-7).
A few metals were detected in some samples above their respective PQLs. They included
antimony, which was detected in one sample (58.1 mg/kg dw); cadmium, which was detected
in one sample and its duplicate (1.5 and 1.7 mg/kg dw, respectively); copper, which was
detected in five samples at concentrations ranging from 7.0 to 29.4 mg/kg dw; and silver^
which was detected hi two samples at concentrations of 12.6 and 13.9 mg/kg dw (Table 2-6).
Sodium and vanadium were detected in several soil samples above their respective method
detection limit but below their PQLs. Lead was detected in 16 of the 18 soil/weathered-rock
samples. Detected concentrations of lead ranged from below the PQL of 0.9 mg/kg dw to
19,600 mg/kg dw (duplicate of P3-SL-0031). The elevated concentration of lead was
confined to.sample P3-SL-0031. In this sample, the lead concentration levels were 6,830
mg/kg dw for the surficial sample (0 to 1 foot bgs), 19,600 mg/kg dw for its duplicate, and 59
mg/kg dw for the subsurface sample (1 to 2 feet bgs). Remaining lead concentrations did not
exceed 627 mg/kg dw as shown on Figure 2-5. The aerial extent of elevated lead levels in
18
-------
P3-SL-0030 marten dw
::=:= Onlr»g» Ottcft
HMV
-------
the subsurface appears to be confined to the original disposal area in the northern portion of
the site. A specific source of lead cannot be ascertained although some of the asphalt
materials present on site might be a possible source for lead.
Low levels of arsenic ranging from 4.3 to 11.7 mg/kg dw, and mercury ranging from 0.05 to
0.45 mg/kg dw, were also detected.
2.6.1.2 Groundwater Contamination
Ground water samples were collected during the 1988 and 1993 investigations. During the
1988 investigation, groundwater samples were collected from each of the soil borings drilled
during the soil investigation. The groundwater samples were analyzed for organochlorine
pesticides and chlorinated herbicides, which were not detected in any samples. During the
1993 field investigation, samples were collected from two newly constructed wells located it
the area of highest soil contamination (Figure 2-6). Monitoring well P3-MW-0001 was
screened at approximately 15 feet bgs. Monitoring well P3-DMW-0001, considered a deep
monitoring well, was screened at approximately 40 feet bgs. The deep monitoring well was
installed next to P3-MW-0001 to identify vertical migration of contaminants, if present, in
groundwater at Site OT-1 l/OU-2. Results of the groundwater analyses are discussed below
for each of the analytical groups, and are presented in Table 2-8.
Volatile Organic Compounds. VOCs were analyzed for only in the groundwater samples
collected in 1993. No VOCs were detected in the groundwater samples.
Base/Neutral and Acid Extractable Compounds. Eleven BNAs were detected in the two
groundwater samples (shallow, shallow duplicate, deep samples) collected in 1993 at
concentrations above the method detection limit but below the PQL. Concentrations of total
BNAs ranged from 1.2 to 10.8 ug/L and concentrations of PAHs ranged from 0.3 to 8A ug/L
(Figure 2-6). Four BNAs were detected in all samples (P3-MW-0001, P3-DMW-0001, and
duplicate P3-MW-9001): phenanthrene at concentrations ranging from 0.1 to 3 ug/L,
fluoranthene at concentrations ranging from 0.1 to 2 ug/L, pyrene at concentrations ranging
from 0.1 to 0.4 ug/L, and di-n-octylphthalate at concentrations ranging from 0.07 to 0.1 ug/L.
The remaining BNA compounds detected, including naphthalene, acenaphthylene,
dibenzofuran, diethylphthalate, fluorene, and carbazole were all detected in P3-DMW-001 at
concentrations less than 1.0 ug/L.
19
-------
Total PAH 0.3 pal
Total PAH 8.4 uol
Air Fora*
RAMTV*
Storaga AIM
9 Monttoftng Wai Location
<§> D««p MorttertnQ W»I toutlon
::=:= Drmlnag* Often
Canal
FbwC3*f«aton
Haavly VcgRatod Araa
(Rutttf* Mound)
U.S. ARMY CORPS OF ENGINEERS
HOMESTEAD ARB
TOTAL POLYNUCLEAR AROMATIC
HYDROCARBON CONCENTRATIONS
DETECTED IN GROUNDWATER SAMPLES COLLECTED
DURING THE 1993 INVESTIGATION
ATSITEOT-11/OU-2
0 100 200
mm^Smiiim
SCALE IN FEET
-------
TABLE 2-1
SUMMARY OF CONSTITUENTS DETECTED IN GROUNDWATER SAMPLES
COLLECTED IN 19W AT SITE OT-ll/OU-2
RESIDUAL rCSTICIDE DISPOSAL AREA
HOMISTEAD AIR RESERVE BASE, FLORIDA
Parameter
Florid.
Grosjadwater
GaManc*
Co.e."
EPA
Drinking
Water
Standard.
EPA Maximal
CoaUBlaaat
Lev*! Goal
Weill-D.
P3-MW-OOOI
P3-MW.9MI
F3-DMW-WMI
Volatile Organic Compounds
Baaa/Naitnl and Add
EitractaM* Cenpomds
Naphthalene
AceaapbibytaM
Aceaaphtnene
Dibenzbfuran
Dietnylpbihalat*
FluorcD*
Phraanthrat
Cutuole
Di-»-butyloblhalat«
FluonatbdM
Butyibeazylpotbalau
bia(2-Etnyla«yl)pnihalau
Di-n-ocrylshuuuai*
OrfaMchisruta
Pesdddo/rCB« (ug/L)
10
1 0
20
NS
5.600
1 0
1 0
NS
700
42
10
1.400
1 4
1 0
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
4*
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
a-
NS
10
10
10
10
10
10
(O.I)
10
(0.2)
(O.I)
(O.I)
(0.2)
(O.S)
10
ND
U
U
ND
10
10
10
10
10
10
(0.2)
10
(0.2)
(O.I)
10
(0-4)
(0.6)
(0.07)
ND
U
U
(0.3)
(0.2)
(0.4)
(0.4)
(0.2)
(0.6)
0)
(0.9)
10
m
(0.4)
(0-3)
(2)
(O.I)
ND
U
U
Mtubi Ot/L)
Barium
Calcium
Chromium
Iron
Magnesium
Polauium
Sodium
Cviold* (ug/L)
Total Dtoaolvad Solids («i/L)
1,000*
NS
50»
300*
NS
NS
160.000*
154
500*
2.000*'
NS
100*'
300*
NS
NS
NS
200'
500*
2,000*
NS
too'
NS
NS
NS
NS
200'
NS
< 10
103.000
46.1
< 50
(3.490)
12.900
16.400
< 10
3SO
(10)
101,000
46.9
< 50
(3.460)
13.000
16.500
< 10
340
< 10
100.000
< 10
(55)
(3.460)
7.S50
13.800
< 10
380
Note*:
Honda Grouadwater Guidance Concenniioaj for Minimum Criteria Requirement* (Rule 17-3.402. FAQ. Florida Department of Environmental Protection. February 1989.
' Florida Primary Drinking Waur Standard.
Numben repraenl EPA't Final MCL (Maximum rnrinmnurm LtvctoX
' Numben represent EPA'i Final MCL errectn* Jury 1992. Federal Regular. January 30. 1991.
' Numben repraenl EPA'i Proposed Primary MCL. Federal Regitter, Vol. 55, No. 143. July 1990.
' Numbers represent EPA'i Primary MCL for Imngankj.
i
Florid* Secondary Drinking Water Standard.
ND No< detected, none of the compounds in this anaryu group were detected above toe detection limit.
MS No ftaadard applicable
ug/L mjcrogrami par liter
tng/L milligrams per liter
< Anaryte was not detected at or above tbe indicated eoneentnuona. Values given an equal in the requested quantiation
3 Value u greater than innrumcot detection limit but la* than practical qusnntation limit
I Positive result baa been classified as qualitative.
UJ Analyte wu not detected or baa bean classified as iirifhm ud, with further classification.
U Classified or undetected.
From: Geraghty * Millar, Inc., 1993*
-------
Organochlorine Pesticides/PCBs. No pesticides/PCBs were detected in the groundwater
samples collected during the 1988 and 1993 investigations.
Inorganic Constituents. Calcium, magnesium, potassium, and sodium were detected in all
three groundwater samples (P3-MW-0001, P3-DMW-0001, and duplicate P3-MW-9001)
collected in 1993, as shown on Table 2-8. However, there are no Federal or State Primary
Drinking Water Standards for these constituents. Barium, chromium, and iron were detected
in some of the groundwater samples at maximum concentrations of 10 ug/L, 48.9 ug/L, and.
55 ug/L, respectively. These concentrations are well below their respective Federal and State
Primary Drinking Water Standards (Table 2-8).
2.6.13 1 Sediment Contamination
Sediment samples were cotteTTe7r3uring the 1991 and 1993 field investigations. A total of
six sediment samples were collected in 1991; three sediment samples (P3-SD-0001, P3-SD-
0004, and P3-SD-0006) were collected from the ditch system which transects Site OT-
ll/OU-2, and the remaining three sediment samples (P3-SD-0007 through P3-SD-0012)
were collected from Boundary Canal. In 1993, three sediment samples (P3-SD-0010 through
P3-SD-0012) were collected from the ditch system; and one sample (P3-SD-0014) was
collected from the Boundary Canal upgradient of Site OT-1 l/OU-2.
»
A summary of the analytical results for sediments is presented in Tables 2-9 and 2-10 and
Figures 2-7 to 2-9. The analytical results are discussed below for each analyte group. The
potential impacts to sediments in the Boundary Canal (OU-9) are addressed in the Remedial
Investigation/Baseline Risk Assessment Reports for OU-9.
Volatile Organic Compounds. The only VOCs detected during the 1991 and 1993 field
investigations were acetone and methylene chloride. Both acetone and methylene chloride
are common laboratory artifacts and, at the concentrations detected, are not believed to be
representative of site contamination.
Base/Neutral and Acid Extractable Compounds. A number of BNA compounds were
detected in the samples, as shown in Tables 2-9 and 2-10, and Figure 2-7, all of which were
PAHs. During the 1991 investigation, all of the PAHs reported in samples P3-SD-0007 and
P3-SD-0009 were detected above the detection limit but below the PQL. Ten PAH
compounds were detected in sample P3-SD-0008 at concentrations above the PQL including
20
-------
P3-SD-0013M993)
P3-SO-0013" _ ~ _~_
P>SO-0007f1OT1)
TOUIPAH 3.500 K0*gtfw
Air Pom
R*M«V*
S to rag* ASM
P3-50-0010 (1993)
Total PAH 32.700 pgftg dw
P3-S04012nM3)
TOUIPAH 7.0SS|JOykgdw
P3-SCHM11 (1M3)
P3-StX)008M991)
Tolal PAH | 18.930 po*g dw
+ SKftMrt Simpte Location
0«*lgn*lton OcnolM PIMM:
P3-SO000110 Pl-SO-0008 (1M1 C£RO> Plus* I)
P3-S£M»10 to P3-SD0013 (1093 CERCLA PtMM II)
P3-SO-0009(1991)
[ - | OpanGrasaMnd
HMvlVV«gtal*
(Ri*bl» Mouno)
U.S. ARMY CORPS OF ENGINEERS
HOMESTEAD ARB
TOTAL POLYNUCLEAR AROMATIC
HYDROCARBON CONCENTRATIONS
DETECTED IN SEDIMENT SAMPLES COLLECTED
DURING THE 1991 AND 1993 INVESTIGATIONS
ATSITEOT-11/OU-2
0 100 200
z=s^;
SCALE IN FEET
-------
Air Force
Storage Ar»a
P3-SO-OOM (1M1)
P3-SOO011/9011 (1993)
Scdnwrt Sanpi* LooUon
P>SD-0001 to P3-SD-0008 <1M1 C£RO> Pf»M I)
P3-SOO010 lo P>SO«Ot3 (1883 CERCIA PtwM U)
NO hMO*MClwt
H»«vi»y V*glal«0 ATM
(RuOM* Mound)
U.S. ARMY CORPS OF ENGINEERS
HOMESTEAD ARB
PESTICIDE CONCENTRATIONS
DETECTED IN SEDIMENT SAMPLES COLLECTED
DURING THE 1991 AND 1993 INVESTIGATIONS
AT SITE OT-11/OU-2
100 2OO
5=
SCALJE IN FEET
-------
Air Fore*
R«M(V«
Storage Area
MaiaJ
Arsenic
Chromium
Coppef
Lead
Mercury
Zinc
tnq/kg / Duplicate
58/13
c3.5 / <3.6
6.6/8.3
<0.014 / <0.014
99/45
M-SD-0011 (1993)
M*U1
Anant
Chromium
COppW
Laad
Mareury
Zkc
moAg/Oupdcaii
<3.9/11J
14.3/13.5
17.9/17.9
40.3/35.1
<0.09S/0.10
r 18.0 / 14.3
Ordnance
LEGEND
P3-SO-OO01 to P3-SOOOOQ (1991 CERCLA PhaM I)
P3-SO-0010 to P3-SCXXM3 (1993 CERCLA Ph«M II)
NA NotAnalyzwl
:=:= Dnk«o*Mcti
^HOI Canal
:g::ft| Hoavly VagKatwl ATM-
-1 (Ri^bto Mound)
I ^.1 Qpan Qmialand
FtowCXrwaton
U.S. ARMY CORPS OF ENGINEERS
HOMESTEAD ARB
METAL CONCENTRATIONS
DETECTED IN SEDIMENT SAMPLES COLLECTED
DURING THE 1991 AND 1993 INVESTIGATIONS
ATSITEOT-11/OU-2
FIGURE 2-9
-------
P>SD-0007(19«1)
P3-SO-0010(1993)
Atr Force
FUterva
Storage Area
P3-SO-OO08 (1991)
PI-SO-0011/9011 (1993)
PJ-50-0009(1991)
Suf«o> Water Samptt Location
P3-SW-0001 to P>SW-0000 (1001 CCRCLA Phu« I)
P3-SVW»10K>P>SW-0013(1003CEftCX*Ph«»«ll)
MA NotAmlyzM
NO NolDctMUd I- _*l Op«»Q«»Jtand
:=:= Dralnag* Ottch
HMVIIy V«gtaMd VM
(Rubbto Mound)
U.S. ARMY CORPS OF ENGINEERS
HOMESTEAD ARB
METAL CONCENTRATIONS DETECTED IN
SURFACE WATER SAMPLES COLLECTED
DURING THE 1991 AND 1993 INVESTIGATIONS
ATSITEOT-11/OU-2
0 100 200
2^5=
SCALE IN FEET
RGURE2-10
-------
TABLE 2-9
CONSTITUENTS DETECTED IN SEDIMENT SAMPLES COLLECTED IN 1991 AT SITE OT-ll/OU-2
RESIDUAL PESTICIDE DISPOSAL AREA
HOMESTEAD AIR RESERVE BASE, FLORIDA
Sample Identification
Analyte Sampling Date
Volatile Organic Compound* 0*g/kg dw)
Acetone
Melhylene Chloride
Metals (mg/kg dw)
Aluminum
Arsenic
Barium
Calcium
Chromium
Cobalt
Copper
Iron
Lead
Magnesium
Manganese
Mercury
Sodium
Vanadium
Zinc
P3-SD-0001 P3-SD-0004
8/23/91
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
8/24/91
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
P3-SD4006
804V91
NA
NA
NA
NA
NA
NA
NA
NA <
NA
NA
NA
NA.
NA
NA
NA
NA
NA
P3-SD-0007
1073/91
23 J
5.3 J
2,100
5.0
7.9
310.000
8.4
1.5
5.7
900
13
880
17
0.025
460
4.8
12
P3-SD-0008 P3-SD-9008
10/3/91
19
5.3
1.100
< 1.4
6.4
270.000
5.8
< 1.4
< 3.5
570
6.6
690
13
< 0.014
510
2.9
99
10/3/91
J 45
J 3.3 J
1.200
< 1.5
69
370.000
13
< 1.4
< 3.6
640
8.3
1. 100
17
< 0.014 <
640 <
3.7
45
P3-SD-0009
10/3/91
!
64
9.9
1.500
6.9
10
310,000
3.3
3.3
8.7
1.400
27
700
23
0.029
500
7.3
37
J
J
Base/Neulrml-Add Extractable Compound! (jig/kg dw)
Anthracene NA
Benzo(a)anthxacene
Bcozo(i)pyreae
Benzo(b)fluoranthene
Benio(gXl) perytene
BeruodOfluoranlhene
Bis(2-Elhylhuyl)phthalaie
Chrysene
Dibenzo(a,h)afflhraccne
Fluoranlhene
lndeoo(l.2,3-cd)pyrene
Pheaanthiene
Pyreoe
Chlorinated Pesticides (m/kg dw)
4,4'-DDD
4,4' -DDE
4,4' -DDT
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
< 140 <
67 J <
< 360 <
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
160
160
390
NA <
NA <
NA
NA
NA
NA
NA <
NA
NA <
NA
NA
NA
NA
< 71
73
< 180
850
850
340 J
350 J
250 J
340 i
850
390 J
850
790 J
240 J
280 J
520 1
960
280
250
290
1.700
1,800
2,200
1.200
420
1.300
1.900
520
3,400
1,100
1.200
3.200
< 60
< 60
< 150
J NA <
NA <
NA
NA
NA <
J NA
NA
NA <
1 NA <
NA
NA <
NA <
NA
< 60 <
< 60 <
< 150 <
1,100
1.100
120
130
1.100
110
140
1.100
1.100
190
1.100
1.100
150
120
120
290
J
J
J
Ji
J
)
Result hu been classified as qualitative due to enrols) in associated quality control analyses.
fig/kg dw Micrognms per kolgraro dry weight
mg/kg dw Milligrams per kilogram dry weight.
< Aoalyte was not detected. Values given an equal to the practical quantitan'on limits' requested in the Rl Wotfc Plan and may
water content, mass analyzed, and dilution factor*.
vary among samples due to differences in
NA Simple was not analyted for the indicated analyles.
1 Value is greater than instrument detection limit but leu than practical quantiiation limit..
From:
Genghty & Miller. Inc.. I991a
-------
TABLE H«
CONSTITUENTS DETECTED IN SEDIMENT SAMPLES COLLECTED IN 1993
AT SITE OT-1 l/OU-2, RESIDUAL PESTICIDE DISPOSAL AREA
HOMESTEAD AIR RESERVE BASE, FLORIDA
(Pate 1 of 2)
Parameter
NOAA
ER-L*
Value
NOAA
ER-Mk
Value
Uterlro
SQC
(ui/ktOC)c
P3-SD-OOI*
P3-SD-OOII
(Duplicate)
P3-SD-9011
P3-SD-0012
P3-SD-0013
Volatile Ortank Compound.
(t«/k«dw) "^
Mdhylene Chloride
Acel00e
Bate/Neutral and Acid ExUaclabte
Caibazole
±
Bcu«*b)(luonalheae
Dibenzo/unu.
Ortaaochlorine PeitkUei/PCBt (jn^j
W4.4'-DDE
4.4--DDD
Umma-Chlofdue
Aluminum
Btriuni
ChromiufQ
SodiiLn
r
Ar»«nic
N
JJ
«
i
N
N
N
7
s
N
2
2
(W.
OJ|
OA
.
NJ
(6)
44
960
5
N
M
2
...
N
»
«.
< 4.1
< 4.1
< 2.1
< 2.1
738
< I2.J
412.000
5.9
< 6.3
514
(»J2)
11.8
(66J)
0.4)
11.7
4.1
< 2.5
< 0.062
U
)
20
20
650
650
(U)
650
650
(340)
(340)
(140)
(260)
650
650
(340)
(270)
(230)
(170)
650
(170)
650
UJ
2.660
(10.7)
304.000
14.3
17.9
2.170
(1.160)
65.4'
(447)
(5.7)
16.0
0.095
UJ
18
IS
< 580
< 580
(97)
< 580
< 580
(340)
(280)
(130)
(230)
(SO)
< 580
(360)
(110)
(190)
(170)
(38)
(170)
< 580
UJ
2.110
(M.O)
311.00
0
13.5
17.9
1.790
I.I 10
65.2
(444)
(5.4)
14.3
0.10
UJ
91
750
6.0
6.0
3.1
3.1
3.220
(14.0)
223.000
17.1
13.9
2.930
(936)
58.1
(433)
(8.0)
43.2
21.9
3.6
0.081
19
19
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
610
610
610
610
610
(SO)
(43)
610
610
610
610
(46)
610
610
610
610
610
610
UJ
< 6.1
< 6.1
< 3.1
< 3.1
8.450
(10.5)
143.000
47.5
< 9.2
9.190
(734)
37.5
(274)
30.6
12.1
33.0
4.0
< 0.083
UJ
UJ
UJ
UJ
-------
TABLE MO
CONSTITUENTS DETECTED IN SEDIMENT SAMPLES COLLECTED IN 1993
AT SITE OT-I l/OU-2, RESIDUAL PESTICIDE DISPOSAL AREA
HOMESTEAD AK RESERVE BASE. FLORIDA
(Page2of2)
Parameter
NOAA NOAA Interim
ER-U ER-Mk SQC
Valiw Value (Mg/kg OCX
P3-SD-0010
P3-5D-M11
(Duplicate)
P3-SD-M11
P3-SD-0012
P3-SD-OOI3
Cyanide (mf/k| dw)
Total Organic Carbon (mg/kg dw)
AVS Extractablc Metal* (mf/kg dw)
Copper
Zuc
Lad
Add VaUtik Sulflde (me/kg dw)
NS
0.31
2.500
13
11.6
4.5
13
0.49
24.000
27.3
8.9
21.1
31
0.44
21.000
6.5
10.4
20.8
29
0.45
33,000
3.3
36.7
12.5
210
< 0.46
34.000
3.3
BJ
9.6
19
National Oceanic tod Atmospheric Administration.
Effect* Range - Low value* are concentrations equivalent to the Iowa 10 percentile of available dau screened by NOAA and indicate the low end of the range of concentration* in tpecific sedimenu it which adverse biological
effect! 'were observed or predicted la sensitive specie* and/or sensitive life stage*.
>> Effects Range - Median value* are concentration! based on the NOAA journal data equivalent 10 (he midpoint (50th percenlile) of the range of available data screened by NOAA.
c OC is Organic Carbon. Before comparing Interim Sediment Quality Criteria (SQC) with the concentrations of constituent* detected in a sample, the detected sediment concentrations must be normalized to the average percent
combustible matter assumed to be organic carbon.
« Fresh Water Final Chronic Value (FCV) Sediment Quality Criteria.
' The sediment quality criteria (SQC) cannot be directly compared with the Boundary Canal and drainage ditch data because the SQC are presented as normalized to ortanic carbon (i.e., presented on a per organic carbon weight
basis). To allow a direct comparison between Boundary Canal and drainage ditch dau and SQC. the SQC for the average carbon content, 2.3% OC, in Boundary Canal and drainage ditch sediments were calculated. The SQC
(ug/kg) at 2.3% OC were derived by multiplying the SQC (ug/kg OC) by the average OC content of 2.3% (.023 kg of OC/kg of sediment).
i NOAA ER-L A ER-M values for total OUordane.
* Ruuli from reanalysis of sample
NS No Standard Available
N No NOAA ER-L or ER-M value available.
ug/kg dw micrograms per kilogram dry weight
rng/kg dw milligrams per kilogram dry weight '
< Analyte was not delected at or above the indicated concentration.
1 Positive result has been classified as qualitative due to deficiencies in one or more quality control measures.
() Result is greater than instrument detection limit but less than practical quaniilation limit.
UJ Analyte was not detected or has been classified as undetected, with further classification as qualitative.
U Classified as vndfffrffd
I' I Concentration above NOAA or Sediment Quality Criterion To-Bc-Considered Guidelines.
From: Genghly A Miller, I993a
-------
benzo(a)anthracene, benzo(a)pyrene, benzo(b)fluoranthene, benzo(g,h,i)perylene,
fluoranthene, indeno(l,2,3-c,d)pyrene, phenanthrene, and pyrene (Table 2-9).
During the 1993 field investigation, a total of 18 BNA compounds were detected as shown
on Table 2-10, all of which were PAHs. Total PAH concentrations ranged from 139 to
32,790 ug/kg dw (Figure 2-7). All of the PAHs reported in sample P3-SD-0011 and
duplicate P3-SD-9011 were detected above the detection limit but below the quantitation
limit. Eleven PAHs (including acenaphthene, phenanthrene, fluoranthene, pyrene,
benzo(a)anthracene, benzo(a)pyrene) were detected in sample P3-SD-0010 at concentrations
above the practical quantitation limit (Table 2-10). The highest levels of PAHs in sediment
occurred at the confluence of the drainage ditch and the Boundary Canal. No PAH sources
are present on site at that location. In the canal, at the northern area of the site (by the rubble
pile), none of the PAHs exceed NOAA ER-M values. The area is heavily overgrown at the
location of the elevated PAH concentrations in the soil; and runoff is unlikely at that location.
Due to the abundant vegetation at the site, surface water runoff during normal rain events is
expected to be minimal. However, under heavy rain storms, surface water runoff to the
drainage ditch and the Boundary Canal is possible. The canal system at Site OT-ll/OU-2
has been evaluated under OU-9 -Boundary Canal.
N
Organochlorine Pesticides. During the 1991 field investigation, only 4,4'-DDE was
detected in sediment samples collected from the ditch, at a concentration of 67 u,g/kg (P3-
SD-0001) and 73 |ig/kg (P3-SD-0006) as shown in Figure 2-8. In the sediment samples
collected from the Boundary Canal, three organochlorine pesticides were detected in sample
P3-SD-0007: 4,4-DDD, at a concentration of 960 U£/kg; 4,4'-DDE, at a concentration of 280
Hg/kg; and 4,4'-DDT, at a concentration of 250 Jig/kg. Figure 2-8 depicts the areal
distribution of pesticides detected in the sediments at Site OT-ll/OU-2. During the 1993
investigation, four pesticides were detected in sediment samples P3-SD-0011 and duplicate
P3-SD-9011: 4,4'-DDD at concentrations of 6.5 and 5.6 Jig/kg, respectively; 4,4'-DDE at
concentrations of 82 and 67 u,g/kg, respectively; alpha-chlordane at concentrations of 11 and
12 M-g/kg, respectively; and gamma-chlordane at concentrations of 12 and 15 M-g/kg,
respectively (Table 2-10). No other pesticides were detected in the OT-ll/OU-2 sediment
samples. Forty-nine soil samples were collected at Site OT-ll/OU-2, and only three had
pesticide levels slightly higher than the maximum concentrations detected in the sediment
samples. No pesticides were detected in the groundwater wells located in the immediate
vicinity of these soil samples. The dense vegetation and distance (approximately 500 feet) to
the canal makes stormwater runoff entering the canal unlikely. However, during heavy rain
storms, surface water runoff to the drainage ditch and Boundary Canal is possible. Pesticides
21
-------
were not detected in Boundary Canal sediment samples collected downstream of the
confluence of Boundary Canal and the OT-1 l/OU-2 drainage ditch in the vicinity of Site OT-
1 l/OU-2. The canal system at Site OT-1 l/OU-2 has been evaluated under OU-9 - Boundary
Canal.
Inorganic Constituents. During the 1991 and 1993 sampling rounds, 15 metals were
detected in sediment samples collected from the drainage ditch and the Boundary Canal, as
shown in Table 2-9 and 2-10. The metals with the highest concentrations in the sediment
samples were calcium, aluminum, magnesium, iron, and sodium. The remaining metals,
including arsenic, barium, chromium, cobalt, lead, mercury, and vanadium, occurred in trace
concentrations. The concentrations of metals detected in the Site OT-1 l/OU-2 sediment
samples appear to be typical of sediments having a carbonate bedrock source and were
representative of background soils (Table 2-7). Figure 2-9 depicts the area! distribution of
metals of concern.
2.6.1.4 Surface Water Contamination
The surface-water quality at Site OT-1 l/OU-2 was evaluated during both the 1991 and 1993
investigations. In 1991, six surface-water samples were collected from the same locations as
the sediment samples: three samples (P3-SW-0001, P3-SW-0004, and P3-SW-0006) from the
ditch system which transects Site OT-1 l/OU-2, and three samples (P3-SW-0007 through P3-
SW-0009) from Boundary Canal. All six samples were analyzed for chlorinated pesticides.
In addition, three of these samples (from the Boundary Canal), including the upgradient
sample, were analyzed for TCL VOCs, TCL BNAs, and TAL metals. In 1993, three surface
water samples (P3-SW-0010, P3-SW-0011, andP3-SW-0012) and one background sample
(P3-SW-0013) were collected from Site OT-1 l/OU-2 and analyzed for TCL VOCs, TCL
BNAs, pesticides, and TAL metals. A summary of the analytical results is presented in
Tables 2-11 and 2-12 and Figure 2-10. Results of the analyses are discussed below for each
analyte group (i.e., VOCs, BNAs, etc.). Surface water impacts to the canals are addressed in
the OU-9 Boundary Canal RI/BRA Reports
Volatile Organic Compounds. Only one VOC was detected in the surface water samples.
Bromodichloromethane was detected in sample P3-SW-0010 at a concentration of 1.0 \ig/L
and was also detected in the background sample, P3-SW-0013, at the same concentration.
The practical quantitation limit for bromodichloromethane is 10 Hg/L, which is substantially
greater than the detected concentration. Bromodichloromethane, a disinfection by-product, is
a trihalomethane commonly found in drinking water.
22
-------
P3-SD-0010(1983)
Air Force
R«Mrve
Storage Area V
, , T^*^<»*sv«Mft
;"" *, ' f-.v/'fVAf\fff '-. ^ >ff '
P3-E:M>OOa(1991)
P3-SO4011/M11 (1993)
P»-S(V0009(1991)
9 Surt«<»W«UrS«mpt»Loe«don
Pl-SW-0001 to P3-SW-0000 (1981 CERCtA PtMM I)
P>W-0010 to P3-SW-0013 (1993 CEACLA Pht*» II)
NA N«Af«lyz«d ,^__
NO NttCMMWl t~ J8! Op««Q«»s(ind
:=:= Drainage Oflch . %* I HMvtty V«gUt«d VM
(Ruttoto Mound)
U.S. ARMY CORPS OF ENGINEERS
HOMESTEAD ARB
METAL CONCENTRATIONS DETECTED IN
SURFACE WATER SAMPLES COLLECTED
DURING THE 1991 AND 1993 INVESTIGATIONS
ATSJTEOT-11/OU-2
FIGURE 2-10
-------
TABLE Ml
CONSTITUENTS DETECTED IN SURFACE WATER SAMPLES COLLECTED IN 1991 AT SITE OT-ll/OU-2
RESIDUAL PESTICIDE DISPOSAL AREA
HOMESTEAD AIR RESERVE BASE, FLORIDA
Analyte
METALS (ns/L)
Barium
Calcium
Copper
Magnesium
Manganese
Potassium
Sodium
Zinc
Simple IdentlflutioD P3-SW-0001
Sampling Date IOV91
NA
NA
NA
NA
NA
NA
NA
NA
P3-SW-0004
WAI9\
NA
NA
NA
NA
NA
NA
NA
NA
P3-SW-0006
1/24/91
NA
NA
NA
NA
NA
NA
NA
NA
P3-SW-90M
10491
NA
NA
NA
NA
NA
NA
NA
NA
P3-SW-0007
1KV91
12
99,000
< 2.0
2.800
< 10
6,700
12,000
< 20
P3-SW-0008
10091
13
87.000
< 2.0
2.300
10
4.300
10.000
22
P3-SW-9008*
10001
13
88.000
< 2.0
2.300
10
4.400
9,800
< 20
P3-SW-0009
10/3/91
I
12
98.000
< 2.0
2.800
< 10
6.900
1.200
< 20
BASE/NEUTRAL-ACID EXTRACTABLE
COMPOUNDS (Mt/L)
Bis(2-Elnylhe*yl)phihalate
NA
NA
NA
NA
7.2
< 5.0
4.9 Jb
lib
ORGANOCHLORINATED PESTICIDES Oi(/L)
gamma-BHC (Lindane)
< 0.010
< 0.010
< 0.010
< 0.010
< 0.010
< 0.010
< 0.010
0.011
b Result hu been classified as qualitative due to error(i) in associated quality conuol analyses.
i Duplicate analysis for M-SW-0008.
Hg/L microgrtmj per liter.
NA Not analyzed
< Analyte was not detected. Value* given are equal to the practical quaniiution limits requested in the Rl Work Plan and may 'vary among samples due to differences in water content, mass analyzed, and dilution facton
J Value is greater than Instrument detection limit taut lew than practical quaniitation limit.
From: Ceraghty A Miller, I991a
-------
TABLE M2
CONSTITUENTS DETECTED IN SURFACE WATEB SAMPLES COLLECTED IN 1993
AT SITE OT-ll/OU-2, RESIDUAL PESTICIDE DISPOSAL AREA
HOMESTEAD AIR RESERVE BASE, FLORIDA
Florida Surface- Federal Water
Witer Quality Quatty
Parameter Standard. Criterion* P3-SW-0010
Volatile Organic Compound* Oig/L)
Bromodichloromeihane MS NS (1) <
Bur/Neutral and Add Extractabk
Compounds ()ig/L)
Butylbenzylphihtlile NS NS < 10 UJ
bis(2-Eihylhe*yl)phthalaie NS NS (0.5) UJ
Orgaoochlortne Pesliddes/PCBs (m/L) NO
Mrtals (ng/L)
Calcium NS NS 93.100
Iron ' 1.000 1,000 50.0
Mignesiura NS NS (3.060)
Potassium NS NS 8.140
Sodium NS NS 13,600
Lead 30 S.fc 3.0
Cyanide (Mg/L) <5 5.2 < 10.0 <
Hardoessdng/L) NS NS 245
P3-SW-W11
10
(0.2) UJ
(0.8) UJ
ND
107,000
(94.5)
(3.110)
8.040
13.900
4.9
10.0
280
P3-SW-9011
< 10
< 10 UJ
< 10 UJ
ND
89.300
< 50.0
(3.080)
7.990
13,800
< 3.0
< 10.0
236
P3-SW-0012
< 10
< 10 UJ
(2) UJ
ND
50.500
< 50.0
(2,180)
5,070
11.400
< 3.0
< 10.0
135
1
(Background)
PVSW-W13
(1)
(0.2) UJ
(0.3) UJ
ND
95.500
< 50.0
(3.110)
8.130
13,500
< 3.0
< io.o
251
Nous:
Florida Surface Water Quality Standard for Class 111 fresh surface waters (Rule 17-302.560 and 17-302.510, FAC).
> . Continuous Federal Water Quality Criterion except where otherwise noted.
c Federal Water Quality Criterion calculated using an average hardness value of 222 rog/L.
Mg/L micrograms per liter
mg/L milligrams per liter
< Analyle was not detected at or above the indicated concentrations. Values given are equal to the requested quanu'iation limits and may vary among samples due to dilution factors.
() Value is greater than instrument detection limit but less than practical quantitation limit.
ND Not delected, none of the compounds in this analyte group were delected above the detection limit.
1 Positive result has been classified as qualitative.
UJ Analyte was not detected or has been classified as undetected, with further classification as qualitative.
U Classified as undetected.
From: Gerighry & Miller, Inc., 1993a
-------
Base/Neutral and Acid Extractable Compounds. The only BNA compound detected was
bis(2-ethylhexyl)phthalate, reported in surface water samples P3-SW-0007, P3-SW-9008,
and P3-SW-0009 at a maximum concentration of 11 u,g/L (Table 2-11). Bis(2-
ethylhexyl)phthalate is a common laboratory artifact. The low levels of bis(2-
ethylhexyl)phthalate detected in surface water samples from this site are likely due to
laboratory contamination. No other BNA compounds were detected in the surface water
samples at Site OT-1 l/OU-2.
Organochlorine Pesticides. Only one organochlorine pesticide was reported in one surface-
water sample: lindane (gamma-BHC) was reported at a concentration of 0.011 |ig/L in
sample P3-SW-0009. Lindane was not detected in other soil or sediment samples collected
from the site. No other pesticides were detected in any of the surface water samples.
Inorganic Constituents. In both sampling rounds, calcium, magnesium, potassium, and
sodium were detected in all the surface water samples; however, no water quality standards
or guidelines exist for these metals. Barium was detected at concentrations ranging from 12
JJ.g/L to 13 Jig/L in all samples collected in the 1991 investigation. Manganese was detected
in sample P3-SW-0008 and the duplicate sample P3-SW-9008 at a concentration of 10 u.g/L.
Zinc was detected at a concentration of 22 |ig/L (P3-SW-0008), but was not detected in the
associated duplicate (P3-SW-9008). Iron was detected at a concentration of 94.5 jig/L (P3-
SW-0011), but was not detected in the associated duplicate (P3-SW-9011). Lead was
detected at a concentration of 4.9 u,g/L (P3-SW-0011), but was not detected in the associated
duplicate (P3-SW-9011). None of the detections in surface water samples exceeded Federal
Water Quality Criterion or Florida Surface Water Standards. Figure 2-10 depicts the area!
distribution of the metals detected in surface water samples at Site OT-1 l/OU-2.
2.6.2 Summary
Concentrations of pesticides (e.g., DDT, DDD, DDE, aldrin, dieldrin, methoxychlor, and
chlordane) have been detected in shallow soil samples collected at Site OT-1 l/OU-2 below
the State of Florida Health-Based Soil Target Levels. The samples collected in 1984 were
also analyzed for chlorinated herbicides. Since none of the samples indicated the presence of
herbicides, this analysis was not performed in the subsequent sampling rounds. Soil samples
were also analyzed for VOCs, BNAs, and metals during the 1993 investigation. Eight VOCs
were detected in the soil samples; however, acetone was the only VOC detected at a
concentration above its PQL, and was believed to be a laboratory artifact. A total of 21
BNAs (mainly PAHs) were detected in the soil samples. Total PAH concentrations ranged
23
-------
from 141 to 92,968 ug/kg dw. The elevated concentrations of total PAHs are likely from the
asphalt debris (which contains PAHs) in the overlying fill material. A total of 19 metals
were detected in the soil samples, most within the range of Homestead ARB background.
Lead was detected at concentrations greater than twice the average Homestead ARB
background concentration for soil. Lead concentrations ranged from below 1 to 19,600
mg/kg dw. Of the eighteen soil samples collected during the 1993 investigation, one surflcial
soil sample and its duplicate contained lead concentrations that exceed the FDEP Health-
Based Soil Target Level of 1,000 mg/kg.
Groundwater samples were collected in 1988 and 1993 and analyzed for organochlorine
pesticides, chlorinated herbicides, VOCs, BNAs, and metals. No VOCs, chlorinated
pesticides/PCBs, or herbicides were detected in the samples. Eleven BNAs were detected at
concentrations above their detection limit but below their practical quantitation limit. Seven
metals were detected; however, none of the metals were detected at concentrations above
Federal or State Primary Drinking Water Standards.
Sediment samples were collected in 1991 and 1993 from the drainage swale that transects the
site and from Boundary Canal. Low levels of pesticides (i.e., DDT, DDE, DDD, and
chlordane) were found in four of the samples (three from the swale and one from Boundary
Canal). Metals were detected in four samples from Boundary Canal and six samples from
the drainage swale at total concentrations within background levels. BNAs were detected in
four sediment samples collected from Boundary Canal at total concentrations ranging from
less than 1 mg/kg dw (P3-SD-0009) to 18.93 mg/kg dw (P3-SD-0008), and in three sediment
samples collected from the drainage swale at total concentrations ranging from 2.1 (P3-SD- /
0011) to 32.79 (P3-SD-0010) mg/kg dw.
Surface water samples were collected in 1991 and 1993 from the same locations as the
sediment samples. Samples collected from Boundary Canal and from the swale were
analyzed for organochlorine pesticides, BNAs, VOCs, and metals. No VOCs were detected
in any of the samples. One pesticide, lindane, was detected in one surface sample. This
pesticide was not believed to be prevalent at the site. Several metals were detected in the
surface water samples collected from Boundary Canal. None of the detections in surface
water samples exceeded Federal Water Quality Criterion or Florida Surface Water Standards.
In summary, the environmental media of concern include the soil and sediment at Site OT-
ll/OU-2.
24
-------
2.7 SUMMARY OF SITE RISKS
In order to evaluate^whether existing or future exposure to contaminated media at Site OT-
1 l/OU-2 could pose a risk to human health and the environment, the USAF completed a
Baseline Risk Assessment (BRA) in July 1994, with USEPA oversight of the process. In
evaluating potential site risk, the USAF assumed no further action would be taken to address
contamination at the site. 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
soil, groundwater, sediment, and surface water at Site OT-1 l/OU-2. 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 OT-1 l/OU-2 were based on the
twice background criteria for inorganic chemicals, elimination of lab contaminants and
detection frequency for organic chemical and essential nutrient elimination.
COPCs for soil, groundwater, surface water, and sediment are shown in Table 2-13.
2.9 EXPOSURE ASSESSMENT
In the exposure assessment, the 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.
25
-------
TABLE 2-13
-CONSTITUENTS OF POTENTIAL CONCERN
AT SITE OT-ll/OU-2
RESIDUAL PESTICIDE DISPOSAL AREA
HOMESTEAD AIR RESERVE BASE, FLORIDA
(Page 1 of 3)
Constituent
VOCS
Acetone
Bromodichloromethane
2-Butanone
Carbon Disulfidc
Chloroform
Dibromochloromethane
1,1-Dichloroethene
B_N_AS
Acenaphthene
Acenaphthylene
Anthracene
Benzo(a)anthracene
. Benzo(b)fluoranthene
Benzo(k)fluoranthene
Benzo(g,hj)perylene
Benzo(a)pyrenc
Bis(2-ethylhexyl)phtfaalate
Butylbenzylphthalate
Carbazole
Chrysene
Dibenzo(a,h)anthracene
Dibenzofuran
Diethylphthalate
Di-n-octylphthalate
Grouodwa-
ter
Xb.
Xb
Xb
X«»
Xb
Xb
Soils/
Weathered Rock
X»
Xb
X«.b
Xb
Xb
Xb
Xb
X
X
X
X
X
X
X
X
x«
Xb
X
X
X
Surface
Water
Xb
-
X«
x«
Sediment
X«
X
Xb
X
X
X*
X
X
x«
X
X
Xb
Xb
Xb
Cancer Potential
Class<*
D
B2
D
D
B2
C
C
D
D
D
B2
B2
B2
D
62
B2
C
B2
B2
B2
D
D
D
-------
TABLE 2-13
"CONSTITUENTS OF POTENTIAL CONCERN
AT SITE OT-ll/OU-2
RESIDUAL PESTICIDE DISPOSAL AREA
HOMESTEAD AIR RESERVE BASE, FLORIDA
(Page 2 of 3)
Constituent
Fluoranthene
Fluorene
Indeno( 1 ,2,3-c,d)pyrene
2-Methylnaphthalene
Naphthalene
Phcnanthrcnc
Pyrene
Pesticides
Aldrin
Chlordane (alpha and gamma)
4,4'-DDD
4,4'-DDE
4.4'-DDT
Dieldrin
Endosulfaon
Heptachlor epoxide
Methoxychlor
Milala
Aluminum
Arsenic
Barium
Cadmium
(Chromium
Cobalt
Groundwa-
ter
Xb
Xb
Xb
Xb
Xb
X*
X
Soils/
Weathered Rock
X
X
X
X
X
X
X
X
X
X
X
X
x*>
X
X
X
X
X
_
X
X
Surface
Water
X
Sediment
X
Xb
Xb
X
X
X
X
X
Xc
X
Cancer Potential
Classd
D
D
B2
D
D
D
D
B2
B2
B2
B2
B2
B2
D
B2
D
NA
A
D
Bl
A
NA
-------
TABLE 2-13
""CONSTITUENTS OF POTENTIAL CONCERN
AT SITE OT-ll/OU-2
RESIDUAL PESTICIDE DISPOSAL AREA
HOMESTEAD AIR RESERVE BASE, FLORIDA
(Page 3 of 3)
Constituent
Copper
Iron
Ifatt
Manganese
Mercury
Silver
Vanadium
Zinc
Groundwa-
ter
Xb
Soils/
Weathered Rock
X
X
X
X
X
X
X"
X
Surface
Water
X
X
X
X
Sediment
X
X
X
Cancer Potential
Classd
D
D
B2
D
D
D
D
D
P Common laboratory contaminant
Analytical results are above the method detection limit but below the practical quantitation limit
c Result classified as undetected
-------
2.9.1 Exposure Point Concentration
The exposure poinLconcentration for each contaminant was derived using the 95 percent
upper confidence limit (UCLgs) on the arithmetic mean as defined by the following formula:
(- Sy* SyxH)
= e y + -*-- + :
.._
UCL
2
where: y = arithmetic mean of the log-transformed data
S = standard deviation of the log-transformed data
H = statistical parameter
Often, with limited data sets, the UCL$5 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 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 child 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 formulas used to calculate the GDI for each pathway are also
provided in Tables 2-14 through 2-16.
26
-------
TABLE 2-14
EQUATIONS AND SAMPLE CALCULATIONS FOR HYPOTHETICAL
FUTURE GROUNDWATER EXPOSURE,
SITE OT-ll/OU-2, RESIDUAL PESTICIDE DISPOSAL AREA
Homestead Air Reserve Base, Florida
Equation Definitions
GWExD = EPC x IR x EF x ED
BWxAP
OWE x Dd = EPC x SSA xPCxETxEFxED
BWxAPxUCF
HI = OWE x Da + OWE x D,
RfD0 RfD.
ELCR = (OWE x D0 x CSF0) + (OWE x Dd x CSF.)
where:
AP Averaging period (equal to ED x 365 days/year for non-cancer effects; 25,550 days [365
days/yr for 70 years] for carcinogenic effects (USEPA, 1989a).
BW Body weight (70-kg for an adult: 15 kg for a child [aged 0 to 6])) (USEPA, 199la).
CSF Cancer slope factor for oral (CSFJ or dermal (CSFJ intake (mg/kg/day)'1.
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/L) (Table 3.1).
OWE x D Potable groundwater exposure dose for oral (GWE x DJ or dermal (OWE x DJ 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, 1991a; 1989d).
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 cm for an adult; 5,150 cm for
a child [aged 0 to 6]) (USEPA, 1989d).
UCF Unit conversion factor (1,000 cm /L).
OOC.100OApt29.199S
-------
TABLE 2-14
EQUATIONS AND SAMPLE CALCULATIONS FOR HYPOTHETICAL
FUTURE GROUNDWATER EXPOSURE,
SITE OT-ll/OU-2, RESIDUAL PESTICIDE DISPOSAL AREA
Homestead Air Reserve Base, Florida
(Continued)
Example Calculation: Cancer Effects of Carfaazole (Adult Resident)
OWE x D^ = (0.00090 me/L) (2 L/dav) (350 davs/vear) (30 years)
o
(70 kg) (25,550 days)
1.06E-05 mg/kg/day
OWE x Dd = (0.00090 mg/Uf 18.150 cm2)f0.04 cm/hourK0.25 hour)f350 days/vear)(30 years)
(70 kg) (25,550 days) (1,000 cmVL)
= 9.59E-07 mg/kg/day
ELCR = [(1.06E-5 mg/kg/day)(0.020 kg-day/mg)] + [(9.59E-7 mg/kg/day) (0.020 kg-day/a^i
2.3E-07
»
Non-Cancer Effects of Pyrene (Child Resident)
GWE x D = (0.00040 me/L) (1 L/dav) (350 davs/vear) (6 years)
o
(15 kg) (2,190 days)
= 2.6E-05 mg/kg/day
GWExDd = (0.00040 mg/L) f5.150 cm2) (0.67 cm/hour) fO.25 hour) (350 days/year) (6 years)
(15 kg) (2,190 days]I (l.OOOcmVL)
= 2.2E-05 mg/kg/day
HI = 2.6E-05 mg/kg/day + 2.2E-05 mg/kg/day
3E-02 mg/kg/day 3E-02 mg/kg/day
1.6E-03
Source: Gerachtv & Miller. 1994b ' _
DOC.1008Mfiil29.in6
-------
TABLE 2-15
-EQUATIONS AND SAMPLE CALCULATIONS
FOR SOIL EXPOSURE,
SITE OT-ll/OU-2, RESIDUAL PESTICIDE DISPOSAL AREA
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 1
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/PEFI x ET x EF x ED
aw x AP
( mg/kg/day I
VF - Q/C x '3.14J6 x a x T)"» x u(.-
2 x Dei x Pa x Kas
PEF - Q/C x
UC,
0.036 x (1-G) x |Um/Ur)J x F
Q/C - (exp[ (0.1004 x In(Al) - 5.3466 » (2.92 x sY) ])
( m3/kg J
I (g/mj/secl/(kg/m3) J
sY - 0.02685 x [o.2S * "n(A) " ";°509'*
26.3608
[ unities: J
Dei x Pa
Pa * IPS x (1 -Pal/Kaj]
( cm'/sec I
Dei - Di x (PaJJJ/Pt»)
ELCR - f (SExD. x CSF.) * (SExD, x CSF.) »{SExD, x CSF,)J x TEF
I cm*/sec J
[ unitless I
HI
SExD, ^ SExD, ^ SExD.
RfD. * RfD. * RfO,
I unitless |
where:
.S
AP
Contiguous area of contamination lm:); 4 acres (16.000 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 for a base worker and residents; ED x 7 days/week for an excavation worker) (USEPA. 1989a).
-------
Page 2 of 4
TABLE 2-15
- EQUATIONS AND SAMPLE CALCULATIONS
FOR SOIL EXPOSURE,
SITE OT-ll/OU-2, RESIDUAL PESTICIDE DISPOSAL AREA
Homestead Air Reserve Base, Florida
JR Breathing rate (0.83 m3/hour [20 ma/day| for residents: 2.5 m3/hour 120 mJ/8-hour day| for workers) (USEPA.
19913).
JW Body weight (70 kg tor an adult: 15 kg for a child (aged 0 to 6] [USEPA. 1991 a)).
ISF Cancer slope factor for oral (CSF.J, dermal (CSF.J. or inhalation (CSF.J intake (mg/kg/day) ' fTable 3.101.
3et Effective diffusivity (cm2/sec).
> Oiffusiviry in air (cm^/sec) (Table 3.7).
:D Exposure duration (years or weeks) (25 years for a base'worker (USEPA, 1991a|; 12 weeks for an excavation
worker; 30 years for an adult resident IUSEPA. 1989al; 6 years for a child resident [aged 0 to 61).
IP Exposure frequency (days/year or days/week) (350 days/year for residents IUSEPA, 1991 a]; 12 days/year for
a Case worker; 6 days/week for an excavation worker).
iLCR Excess lifetime cancer risk (unitless).
FPC, Constituent exposure point concentration in the soil (mg/kg) (Table 3.2).
:T Exposure time (2 hours/day for a base worker; 8 hours/day for an excavation worker; 24 hours/day for
residents).
: Function of Ut/Um (0.01261 (unitless); F - 0.18 1 Bx1 + 12x x exp(-x') I. where x = 0.886 (Ut/Um).
:oc Fraction organic carbon in soil (0.02).
3 Fraction of vegetative cover (unitless); conservatively assumed as zero.
H Henry's Law Constant (atm-m3/moll (Table 3.7).
-II Hazard index (unitless).
Incidental ingestion rate for soil (50 mg/day for a base worker; 480 mg/day for an excavation worker; 100
mg/day for an adult resident; 200 mg/day for a child resident (aged 0 to 6]) (USEPA, 199la).
-------
Page 3 of 4
TABLE 2-15
EQUATIONS AND SAMPLE CALCULATIONS
FOR SOIL EXPOSURE,
SITE OT-ll/OU-2, RESIDUAL PESTICIDE DISPOSAL AREA
Homestead Air Reserve Base, Florida
. M.6mg/kg) x Q.ISOcm*) x (1 mg/cm*/d) x 10.03) x (6d/wk) x (12wksl x
(70 kg) x (25.550 d)
- 6.1 x 10-* mg/kg/d
Dei (0.04531 cm'/sec) x (0.06xn/0.437) 2.09 x 10'» cmVsec
Kas » (41 mol/atm/m') x (3.15 x 1Q-7atm-mJ/mol) . 2 69 x 10'1 o/cmj
(240.000 cm 3/g) x 10.02)
(2.09 x 10-»cm'/secl x 0.06 . , 36 x 10-«cmi/fec
0.06 .- I ta.eSg/cm^ x n -0.061/12.69 x 10-'g/cmJ)|
sY - 0.02685 x 10.25 ~ Hn(16.000m»l - 11.05091*1 . Q.008626
[ 26.3608 J
liC - (exp[ (0.1004 x ln[ 16,000m'I) - 5.3466 * (2.92 x 0.008626) ])
- 77.44 (g/m'/secl/ikg/m3)
VF . [77 AA g/m'/sec] v [3.1416 x (1.36 x 1Q-"em'/secl x (7.3 x 10* see)!"* pr>
[ ' kg/m3 J 2 x (2.09 x lO^cm'/secl x 0.06 x (2.69 x lO^g/cm')
2.02 x 10* m'/kg
PEF [77 44 0/rr|2/sec I x 3,600 sec/hour
I " kg/m3 J (0.036g/mj/hr) x (1 -0) x l(4m/sec)/(12.8 m/sec)l3 x 0.01257
- 2.02 x 10'° m'/kg
SExD . (1.6mg/kg) x (2.Sm»/hf) x 111/2.02 x 10*m»/ko)-»M/2.02x T0'8ma/kg)| x (8hf/dl x (6d/wk) x (12wks)
~~ (70 kg) x (25.550 d)
6.4 x 10"u mg/kg/d
ELCR - {((3.1 x 10-«mg/kg/d) x (7.3kg-d/mgll «1(6.4 x 10-'Jmg/kg/d) x (6.1 kg-d/mg)]} x 0.01
- 2.3 x 10-»
(CSF. is not available for chrysene; therefore, dermal exposure is not included in the ELCR calcufation.)
-------
TABLE 2-15 Page4of4
EQUATIONS AND SAMPLE CALCULATIONS
FOR SOIL EXPOSURE,
SITE OT-ll/OU-2, RESIDUAL PESTICIDE DISPOSAL AREA
Homestead Air Reserve Base, Florida
Sample Calculation: Non-Cancer Effects of Mercury (adult resident)
SExD - lO.IOmg/kg) x (IQOmg/d) x (350d/yr) x (30yrs) x
(76kg) x (lO.SSfld)
- 1.4 x 10'7 mg/kg/d
SExD « (0.10mg/kg) x (4.650 cm3) x (1 mg/cmVd) x 0.026 x (350d/yr| * (30yrs» x (10-*kg/mg)
' (?6kg) x ii0.950dt
- 1.7 x 10° mg/kg/d
SExD - (O.IOmg/kg) x [0*(1/2.02x 1Q'°m3/kgH x (0.83 mVhrt x (24hr/d) x (350d/yr> x (30yrs)
" (70kg) x( 10.950 d)
- 1.4 x 10'" mg/kg/d
H, 1.4 x IP'7mg/kg/d ^ 1.7 x IQ'7mg/kg/d ^ 1.4x 10'"mg/kg/d
3 x 10" mg/kg/d 5 x 10-* mg/kg/d 9 x .10'* mg/kg/d
- 0.0038
Source: Geraghty & Miller, 1994b
-------
_ TABLE 2-16
EQUATIONS AND SAMPLE CALCULATIONS FOR
WADING EXPOSURE AT
SITE OT-ll/OU-2, RESIDUAL PESTICIDE DISPOSAL AREA
Homestead Air Reserve Base, Florida
Equation Definitions:
WE x D0 = EPCm x IR^ x ED x EF x ET + EPCri x IRM x ER x Ep
BW x AP BW x AP x UC,
WE x D< = EPC^ x SSA x PC x Uq x ED x EF x ET + EPC^ x SSA x SAR x ABS x ED x EF
BW x AP BW x AP x UC,
ELCR = [(WExD0 x CSF0) + (WExDd x CSFJJ x TEF
HI = (WExD^RfD.) + (WExDyRfDJ
where:
ABS Dermal absorption efficiency (unitless) (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, 1991a).
BW " Body weight (70 kg for an adult; 38 kg for an older child [aged 6 to 15 years]) (USEPA, 1991a; USEPA,
1986b).
CSF Cancer slope factor for oral (CSF,,) or dermal (CSFJ exposure (mg/kg-day)'' (Table 3.10).
ED Exposure duration (25 years for a base worker; 9 years for an older child [aged 6 to 15]).
EF Exposure frequency (12 days/year).
ELCR Excess lifetime cancer risk (unitless).
EPC,, Constituent exposure point concentration in the sediment (mg/kg) (Table 3.4).
EPC,. Constituent exposure point concentration in the surface water (mg/L) Table 3.3).
ET Exposure time (8 hours/day for a base worker; 2.6 hours/day for an older child).
HI Hazard index (unitless).
Incidental ingestion rate of sediment while wading (5 rag/day).
Incidental ingestion rate of surface water while wading (0.005 liters/hour).
PC Permeability constant (cm/hour) (Table 3.11).
RfD Reference dose for oral (RfDJ or dermal (RfDJ exposure (mg/kg-day) (from Table 3.9).
SAR Sediment adherence rate (1 mg/cmVday) (recommended value for soil exposure [USEPA. 1992b]).
SSA Exposed skin surface area (3,120 cm1 for a base worker. 3,715 cm2 for an older child [aged 6 to 15
years]) (USEPA, 1991* 1989d).
TEF Toxicity equvakncy factor for carcinogenic polynuclear aromatic hydrocarbons (PAHs); not applicable
for other constituents (Table 3.10).
UC, Unit conversion 1 (10* mg/kg).
UCj Unit conversion 2 (Iff3 L/cmJ).
WExD Wading exposure dose from incidental ingestion (WExDJ or dermal contact (WExDJ (mg/kg-day).
-------
TABLE 2-16
EQUATIONS AND SAMPLE CALCULATIONS FOR
WADING EXPOSURE AT
SITE OT-ll/OU-2, RESIDUAL PESTICIDE AREA
Homestead Air Reserve Base, Florida
(Continued)
Sample calculation - Bromodichloromethane. cancer effects, base worker
WExD0 = fO.OQIQ mg/L) x (0.005 L/hrt x (25 yrs) x (12 davs/vrt x (8 his/day)
(70 kg) x (25,550 days)
= 6.7E-09 mg/kg/day
WExDd = m.QQIO mp/U xf3.12Q cm2^ xf5.8E-Q3 cm/hrt xflE-03 L/cm3) x(2S vrstem davs/vrtxf8 hrs/davl
(70 kg) x (25,550 days)
= 2.4E-08 mg/kg/day
ELCR = [(6.7E-09 mg/kg/day) x (0.062 kg-day/mg)] + [(2.4E-08 mg/kg/day) x (0.062 kg-day/mg)]
1.9E-09
Sample Calculations - phenanthrene. non-cancer effects, child resident:
WExD0 = (4.2 mf/kg) x (5 mg/day> x (9 yrs") x (12 daysArrt
(38 kg) x (3,285 days) x (1E+06 mg/kg)
= 1.8E-08 mg/kg/day
WExD0 = (4.2 mg/kg^ x (3.715 cm2) « M mg/cmVdav^ x fO.Q3) x (9 yrs> x (12
(38 kg) x ( 3,285 days) x (1E-»O6 mg^cg)
= 4.0E-07 mg/kg/day
HI = 1.8E-Q8 mg/kg/day + 4.0E-07 mg/kg/dav
3.0E-02 mg/kg/day 3.0E-2 mg/kg/day
1.4E-05
Source: Geraghty &. Miller, 19946
-------
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 VOCs, PAHs, pesticides, arsenic, 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 CDI 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 CSF. Use of the approach makes
underestimation of the actual cancer risk highly unlikely. Slope factors are derived from
results of human epidemiologicai 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.
Additionally, COPCs including VOCs, PAHs, pesticides, 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 some contaminants
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 epidemiologicai 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 effects of COPCs are provided hi Table 2-18.
27
-------
TABLE 2-17
CANCER SLOPE FACTORS, TUMOR SITES AND USEPA CANCER CLASSIFICATIONS FOR
CHEMICALS OF CONCERN AT
SITE OT-1I/OU-2, RESIDUAL PESTICIDE DISPOSAL AREA
Homestead Air Reserve Base, Florida
CSF(mg/kg/day)-
Constituent
VOCs
Bromodichloromelhane
Chloroform
Dibromochloromethane
1 , 1 -Dichlorocthane
fiNAs
Benzo(a)anthracene*
Benzo(b)fluoranthene*
Benzo(k)f]uoranthene*
Bcnzo(a)pyrene
Bis(2-ethylhexyl)pnthalate
Butylbenzylphthalate
Carbazolc
Chrysene*
Di benzo(a,h)anthracene*
Indeno(l .2,3-c.d)pyrene*
Pesticides
Aldrin
Chlordane
4,4'-DDD
4.4'-DDE
4.4'-DDT
Dieldrin
Heptachlor epoxide
Oral
6.2E-02
6.1E-03
8.4E-02
6.0E-01
7.3E400
7.3E400
7.3E+00
7.3E+00
1.4E-02
NA
2.0E-02
7.3E+00
7.3E+00
7.3E+00
1.7E+01
1.3E+00
2.4E-01
3.4E-OI
3.4E-OI
16E+OI
9.IE«00
Adjusted [a]
6.2E-02
6.1E-03
8.4E-02
6.0E-01
IAP
IAP
IAP
IAP
I.4E-02
NA
2.0E-02
IAP
IAP
IAP
I.7E401
2.6E+00
2.7E-01
3.8E-OI
3.8E-01
1.6E+01
1.5E401
1
Inhalation
NA
8.1E-02
NA
1.2E+00
6.1E-»00**
6.1E400**
6.1E+00**
6.1E400**
NA
NA
NA
6.1E400**
6.1E+00**
6.1E+00**
I.7E+01
1.3E400
NA
NA
3.4E-01
1.6E401
9.IE400
Tumor
TEF Oral
- Ig. iniestin. kidney
- kidney
- liver
adrenal gland
0.1 NA
0.1 NA
0.1 NA
1 stomach
- liver
NA
- liver
0.01 NA
1 NA
0.1 NA
- liver
- liver
- liver
- liver
- liver
- liver
- liver
site
Inhalation
NA
liver
NA
kidney
NA
NA
NA
respiratory tract
NA
NA
NA
NA
NA
NA
liver
liver
NA
NA
liver
liver
liver
USEPA
Classification
I
B2
B2
C
C
B2
B2
B2
B2
B2
B2
C
B2
B2
B2
B2
B2
B2
B2
B2
B2
B2
Doc. 1008\HomesteacASS-8VT ABLE 2-17
CO/21-May-92
-------
TABLE 2-17
CANCER SLOPE FACTORS, TUMOR SITES AND USEPA CANCER CLASSIFICATIONS FOR
CHEMICALS OF CONCERN AT
SITE OT-ll/OU-2, RESIDUAL PESTICIDE DISPOSAL AREA
Homestead Air Reserve Base, Florida
(Continued)
CSF(mg/kg/day)-l
Constituent
Metals
Arsenic
Cadmium
Chromium VI
Lead
References:
(a]
Oral
Adjusted [a]
I.75E+00 1.8E+01
NAP NAP
NAP NAP
NA NA
Inhalation
5.0E401
6.3E->00
4.1E+01
NA
IRIS, 1994; USEPA. 1993a; USEPA. 1992a.
The CSF adjusted to an absorbed dose was used to assess dermal exposure.
Tumor site
TEF Oral
- skin
NA
NA
NA
Inhalation
respiratory tract
respiratory tract
lung
NA
USEPA
Classification
I
A
Dl
A
B2
The adjusted CSF was derived according
IAP
mg/kg/day
NA
NAP
PAHs
TEF
to USEPA (1989a) methodology by dividing the oral CSF by the constituent-specific oral absorption efficiency (Table 3.11).
The oral and inhalation CSFs for benzo(a)pyitne are used with the appropriate benzo(a)pyrene toxicity equivalency factor
(TEF) values (USEPA, I992a).
The inhalation CSF for benzo(a)pyrene has been withdrawn from HEAST; this value is referenced to a previous issue of
HEAST (USEPA, 1992d).
Not applicable; the TEF is relevant only for the carcinogenic PAHs.
Inappropriate to adjust the oral CSF for carcinogenic PAHs to evaluate dermal exposure (USEPA, 1989a).
Milligrams per kilogram per day.
Not available.
Not applicable since it is carcinogenic by inhalation only.
Polynuclear aromatic hydrocarbons
Toxicity equvalency factor for carcinogenic PAHs.
Source: Geraghty & Miller, 1994b
Doc.1008\HomasteadtSS-B\TABLE 2-17
CD/21-May-92
-------
TABLE 2-18
REFERENCE DOSES FOR CHEMICALS OF POTENTIAL CONCERN,
SITE OT-ll/OU-2, RESIDUAL PESTICIDE DISPOSAL AREA
Homestead Air Reserve Base, Florida
OralRfDo(mK/kg/day)
Constituent .
VOCs
Acetone
Bromodichloromethane
2-Butanone
Carbon disulfide
Chloroform
Dibromochloromethane
1,1-Dichloroethenc
PAHs
Acenapthene
Acenapthylene [b]
Anthracene
Benzo(g4i,i)perylene [b]
Bis(2-ethylhexyl)phthalate
Butyibenzylphthalate
Carbazole
Dibenzofuran [b]
Diethylphthalate
Di-n-octylphthalate
Fluoranthene
Fluorene
2-Methylnapthalene [c]
Napthalene
Phenanthrene [b]
Pyrene
Subchronic
l.OE-KX)
2.0E-01
2.0E-01
l.OE-01
l.OE-02
2.0&O1
9.0E-03
6.0E-01
3.0E-01
3.0E+00
3.0E-01
2.0E-02
2.0E-KK)
NA
3.0E-01
8.0E-MX)
2.0E-02
4.0E-01
4.0E-01
4.0E-02
4.0E-02
3.0E-Q1
3.0E-01
Chronic
l.OE-01
2.0E-02
6.0E-01
l.OE-01
l.OE-02
2.0E-01
9.0E-03
6.0E-02
3.0E-02
3.0E-01
3.0E-02
2.0E-02
2.0E-01
NA
3.0E-02
8.0E-01
2.0E-02
4.0E-02
4.0E-02
4.0E-02
4.0E-02
3.0E-02
3.0E-02
Adjusted RfDa (mg/kg/day) [a]
Subchronic Chronic
l.OE-KX)
2.0E-01
2.0E-01
l.OE-01
l.OE-02
2.0E-01
9.0E-03
5.0E-01
3.0E-01
3.0E+00
3.0E-01
2.0E-02
2.0E-KX)
NA
3.0E-01
8.0E+00
2.0E-02
3.0E-01
3.0E-01
3.0E-02
3.0E-02
3.0E-01
3.0E-01
l.OE-01
2.0E-02
6.0E-01
l.OE-01
l.OE-02
2.0E-02
9.0E-03
5.0E-02
3.0E-02
3.0E-01
3.0E-02
2.0E-02
2.0E-01
NA
3.0E-02
8.0E-01
2.0E-02
3.0E-02
3.0E-02
3.0E-02
3.0E-02
3.0E-02
3.0E-02
Inhalation RfDi
Subchronic
NA
NA
3.0E-fOO
3.0E-03
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
3.7E-04*
3.7E-04*
NA
NA
(mg/kg/day)
Chronic
NA
NA
3.0E-OI
3.0E-03
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
3.7E-04
3.7E-04
NA
NA
Doc.1 OOe\Homfl3tea(ftSS-6\TABLE 2-18
CD/21
-------
TABLE 2-18
REFERENCE DOSES FOR CHEMICALS OF POTENTIAL CONCERN,
SITE OT-ll/OU-2, RESIDUAL PESTICIDE DISPOSAL AREA
Homestead Air Reserve Base, Florida
(Continued)
Oral RfDo (mg/kg/day)
Constituent
Pesticides
Aldrin
Chlordane
4.4--DDD
4,4'-DDE
4,4'-DDT
Dieldrin
Endosulfan
Heptachlor epoxide
Methoxychlor
Metals
Aluminum
Arsenic
Barium
Cadmium (food) [d]
Cadmium (water)
Chromium VI
Cobalt
Copper [e]
Iron
Lead
Manganese (food) (d]
Manganese (water)
Mercury
Silver
Vanadium
Zinc
Subchronic
3.0E-05
6.0E-05
3.0E-03*
7.0E-04*
5.0E-04
5.0E-05
NA
1.3E-05
5.0E-03 .
NA
3.00E-04
7.00E-02
l.OE-04*
5.0E-04*
2.0E-02
6.0E-02*
3.0E-02
NA
NA
1.4E-01
5.0E-03
3.0E-04
5.0E-03
7.0E-03
3.0E-01
Chronic
3.0E-05
6.0E-05
3.0E-03
7.0E-04
5.0E-04
5.0E-05
NA
1.3E-05
5.0E-03
NA
3.00E-04
7.00E-02
l.OOE-03
5.00E-04
5.0E-03
6.0E-02
3.0E-02
NA
NA
1.4E-01
5.0E-03
3.0E-04
5.0E-03
7.0E-03
3.0E-01
Adjusted RfDa (mg/kg/day) [a]
Subchronic Chronic
3.0E-05
3.0E-05
3.0E-03*
6.0E-04*
5.0E-04
5.0E-05
NA
7.8E-06
5.0E-03
NA
3.00E-04
5.00E-03
2.0E-05*
l.OE-05*
4.0E-04
2.0E-02*
2.0E-02
NA
NA
7.0E-03
3.0E-04
5.0E-05
l.OE-03
7.0E-05
9.0E-02
3.0E-05
3.0E-05
3.0E-03
6.0E-04
5.0E-04
5.0E-05
NA
7.8E-06
5.0E-03
NA
3.00E-04
5.00E-03
2.00E-05
l.OOE-05
l.OE-04
2.0E-02
2.0E-02
NA
NA
7.0E-03
3.0E-04
5.0E-05
l.OE-03
7.0E-05
9.0E-02
Inhalation RfDi
Subchronic
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
l.OE-03
NA
NA
NA
NA
NA
NA
NA
l.OE-05
l.OE-05
9.0E-05
NA
NA
NA
(mg/kg/day)
Chronic
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
l.OE-04
NA
NA
NA
NA
NA
NA
NA
l.OE-05
l.OE-05
9.0E-05
NA
NA
NA
Doc.100e\Hon»8tead\SS-eVTABLE 2-18
CO/21-May-92
-------
TABLE 2-18
REFERENCE DOSES FOR CHEMICALS OF POTENTIAL CONCERN,
SITE OT-ll/OU-2, RESIDUAL PESTICIDE DISPOSAL AREA
Homestead Air Reserve Base, Florida
(Continued)
References: IRIS (1994); USEPA (1993a); USEPA (undated [b.c.d]).
* No subchronic value available. Chronic value used as a surrogate.
[a] The RfD adjusted to an absorbed dose was used to assess dermal exposure. The adjusted RfD was derived according to
USEPA (1989a) methodology by multiplying the oral RfD by the constituent-specific oral absorption efficiency (Table 3.11).
[b] No RfD available; pyrene used as a surrogate.
[c] No RfD available; napthalene used as a surrogate.
[d] The RfD for food is used to assess soil exposure.
[e] Based on current Florida Department of Environmental Protection (FDEP) drinking-water standard (1 mg/L).
NA , Not available.
Source: Geraghty & Miller, 1994b
Doc.1008\HoiMlt0ad\SS-8VTABLE2.ie CD/21-
-------
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
future land use scenarios at Site OT-1 l/OU-2 exceed FDEP's 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 (ELCR) 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 range for DOD and Superfund cleanups of between IxlO-4^ 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 = CDIxCSF
where: Risk = a unitless probability of an individual developing cancer
GDI = chronic daily intake averaged over 70 years (rag/kg)
CSF = cancer slope factor, expressed as (mg/kg-day)-1
For current basje workers exposed to site soils, the ELCR is 3 X 107. The ELCR for a base
worker exposed to the surface water and sediments while wading is 6 x 104. The ELCR for a
hypothetical base worker exposed to site soil is 6 x 10"7. The calculated ELCRs for current
and future base workers do not exceed the EPA or FDEP acceptance range risk level.
The ELCRs for a hypothetical future adult and child resident exposed to site soils are 2 x JO4
and 3 x 10"5, respectively. The ELCRs for a hypothetical future adult and child resident
exposed to groundwater are 2 x 10~7 and 1 x lO^i respectively. The ELCR for a hypothetical
older child resident exposed to surface water and sediment while wading is 3 X 10*. The
calculated ELCRs for the hypothetical future adult and child resident exposed to
groundwater, surface water, or sediments do.not exceed the EPA or FDEP acceptable range
risk level. The only unacceptable risk associated with Site OT-1 l/OU-2 were to hypothetical
28
-------
future adult and child residents exposed to site soils. The soils at Site OT-1 l/OU-2 are less ^
ij~' ;
than 6 inches thick and are not continuous across the site. The ELCRs for the hypothetical rf;l
/0L
future adult and chHd residents fall within the EPA target risk range of 10 4 to Iff6 but exceed : *J
the FDEP acceptable risk level of 10 *. S**]
2.9.5.2 Non-carcinogenic Risk. 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 dose 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
which a given population may reasonably be exposed. In general, EPA considers an HI of
1.0 to be the maximum acceptable hazard.
For current base workers exposed to site soils the HI is 0.0004. The HI for a base worker
exposed to surface water and sediments while wading is 0.0003. The HI for a hypothetical
base worker exposed to site soils is 0.03. The calculated Hi's for current and future base
workers do not exceed the EPA or FDEP acceptable risk level.
The HI for a hypothetical future adult and child, resident exposed to site soils are 0.02 and
0.09, respectively. The HI for a hypothetical future adult and child resident exposed to
groundwater are 0.3 and 0.7, respectively. The HI for a hypothetical older child resident
exposed to surface water and sediment while wading is 0.0002.
29
-------
The calculated His for the hypothetical future adult and child residents exposed to soil,
groundwater, surface water, or sediments do not exceed the EPA or FDEP acceptable risk
level.
2.9.5.3 Total Risk. The total site risk for current base workers was obtained by adding the
calculated risk for soil and wading (surface water and sediment) exposures. The total site
ELCR and HI for current base workers were calculated as 3 x 10'7 and 0.0006, respectively.
The total site risk for current base workers do not exceed the EPA or FDEP acceptable range
risk levels. The future base worker was exposed to soils only, so the total site risk is an
ELCR of 6 x 10"7 and an HI of 0.03. The total site risk for future base workers do not exceed
the EPA or FDEP acceptable range risk levels.
Total site risks for hypothetical future residents were obtained by adding the calculated risks
for the adult (groundwater and soil) and for the child (groundwater, soil, and wading). The
total site ELCR for hypothetical future adult resident exposure was calculated as 2 x 10"3, and
the total site HI was calculated as 0.3. For the hypothetical future child resident, the total site
ELCR and HI were 3 x 101* and 0.8 respectively. The total site ELCRs for the future
hypothetical residents are greater than 10* but less than 104, and the total site His do not
exceed the level of acceptable non-cancer risk of 1. The total site risk for hypothetical future
adult residents exposed to soil and groundwater and child residents exposed to soil and
wading fall within the EPA acceptable range but exceed the FDEP range of 10*.
2.9.5.4 Risk from Lead Exposure. Lead exposure was evaluated using the EPA's LEAD5
uptake/biokinethic model designed to assess chronic non-carcinogenic effects from diet,
inhalation, and ingestion of soil, dust, and water. The predicted blood level in the
hypothetical child receptor using an EPC of 390 mg/kg is 3.63 micrograms per deciliter
Qig/dL). The concentration is below the 10 |ig/dL acceptable blood lead level. LEAD5
predicts that 99.82 percent of the hypothetically exposed population of children aged 0 to 6
years would have blood-lead levels below the 10 ug/dL level of concern. The results of the
lead exposure scenario for Site OT-1 l/OU-2 indicate low levels of concern for lead exposure.
2.9.6 Chemicals of Concern and Remedial Goal Option
COCs contribute significantly to a use scenario for a receptor that (a) exceeds a 1Q-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 IxlO'6 or their non-carcinogenic HQ is less than 1. For this site, the relevant
Remedial Goal Options (RGOs) are for PAHs and metals.
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 for soil based on a 104, 10'3, and 10* HI and a 0.1, 1, and 10 HQ have been
developed for this site for each COC, medium, land use, and receptor type. A summary of
the risk-based RGOs are presented in Tables 2-19 through 2-20.
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 lexicological data may not be available for all detected constituents. As a result,
surrogate compounds were used to evaluate PAHs.
Non-carcinogenic risks associated with potential lead exposure were evaluated differently
from other COCs in the risk assessment.
31
-------
TABLBVI9
RISK-BASED REMEDIAL GOAL OPTIONS FOR SOIL
BASED ON HYPOTHETICAL FUTURE ADULT RESIDENT EXPOSURE
SITE OT-ll/OU-2, RESIDUAL PESTICIDE DISPOSAL AREA
HOMESTEAD AIR RESERVE BASE, FLORIDA
(Page 1 of 2)
Constituents
VOCs
Acetone
Bromodichloromethane
2-Butanone
Carbon disulfide
Chloroform
Dibromochloromethane
l.l-Dichloroethene
Acenaphthene
Acenaphthylene
Anthracene
Bcnzo(a)anthraccnc
Benzo(b)flyoranthene
BenzoOOfluoranthene
Benzo(g.hj)perylene
Benzo(a)pyrene
Butylbenzylphthalate
Carbazole
Chrysene
DibenzoCa,h)anthracene
Dibenzofuran
Fluoranthene
Fluorene
IndenoU ,2,3-c,d)pyrene
2-Methylnaphthalene
Naphthalene
Phenanthrene
Pyrene
EPCs
29
0.65
1.5
0.010
0.68
0.68
0.26
0.37
0.068
0.48
0.85
2.7
1.1
0.63
1.7
0.033
0.40'
1.6
0.34
0.53
7.1
0.45
0.69
0.21
0.39
2.1
5.1
Non-Cancer Risk-Based RGOs
THI: | 0.1
5.0E+03
_
1.6E+04
2.7E+02
'
1.6E+03
9.1E+02
9.1E+03
-
-
-
9.1E+02
-
-
-
' -
-
9.1E402
l.OE+03
l.OE+03
-
6.1E+02
3.5E+02
9.1E+02
9.1E+02
1
5.0E+04
_
1.6E+05
2.7E+03
1.6E+04
9.1E+03
9.1E+04
-
-
-
9.1E+03
-
-
-
-
9.1E+03
l.OE+04
l.OE+04
-
6.1E+03
3.5E+03
9.1E+03
9.1E+03
10 |' TCR:
5.0E+05
.. .
1.6E+06
2.7E+04
1.6E+05
9.1E+04
9.1E+05
-
-
-
9.1E+04
-
-
-
-
9.IE+04
l.OE+05
l.OE+05
-
6.1E-KM
3.5E+04
9.IE+04
9.IE+04
Cancer Risk-Based RGOs
| lE-06
1.9E+01
_
2.1E+01
1.4E+01
5.8E-01
a_
-
2.3E+00
[ 2.3E+00 J
2.3E+00
-
| 2.3E-01 |
-
5.8E+01
2.3E+01
| 2.3E-01 |
-
-
2.3E+00
-
-
-
1E-05
1.9E+02
_
2.1E+02
1.4E+02
5.8E+00
_ m
-
2.3E+01
2.3E+01
2.3E+01
-
2.3E+00
-
5.8E+02
2.3E+02
2.3E+00
2.3E+01
-
-
-
lE-04 |
J.9E+03
I
2.1E+03
1.4E+03
5.8E+01
_
-
.
2.3E+02
2.3E+02
2.3E+02
-
2.3E+01
-
5.8E+03
2.3E+03
2.3E+01
_
2.3E+02
-
_
-
-------
TABLE 2-19
RISK-BASED REMEDIAL GOAL OPTIONS FOR SOIL
BASED ON HYPOTHETICAL FUTURE ADULT RESIDENT EXPOSURE
SITE OT-ll/OU-2, RESIDUAL PESTICIDE DISPOSAL AREA
HOMESTEAD AIR RESERVE BASE, FLORIDA
(Page 2 of 2)
Constituents
EPCs
Non-Cancer Risk-Based RGOs
Cancer Risk-Based RGOs
Pesticides
Aldrin
Chlordane
4.4-DDD
4,4'-DDE
4,4'-DDT
Dieldrin
Endosulfan D
Heptachlor epoxide
Methoxychlor
Metals
Aluminum
Arsenic
Cadmium .
Chromium
Copper
Iron
Lead
Manganese
Mercury
Silver
Vanadium
Zinc
0.0050
0.033
0.0064
0.0060
0.034
0.0064
0.0072
0.0040
0.085
5,200
4.6
0.85
17
12
4.900
20,000
69
0.10
3.4
7.1
29
THI: | 0.1
_
-
-
-
3.5E+01
-
-
2.0E+03
-
-
4.9E+03
2.7E+00
3.0E+02
9.0E+01
I.9E+04
1
_
-
-
-
-
3.5E-I02
-
-
2.0E+04
-
-
4.9E+04
2.7E+01
3.0E+03
9.0E402
1.9E+05
10 |
_
-
-
-
3.5E+03
-
-
-
2.0E+05
-
-
4.9E-»^)5
2.7E+02
3.0E+04
9.0E+03
1.9E+06
TCR: | 1E-06
2.1E-02
2.7E-01
2.6E+00
1.8E+00
1.8E-KX)
2.3E-02
2.2E-02
-
I 9.3E-01 J
2.7E+04
4.2E+03
-
-
«
1E-05
2.1E-01
2.7E+00
2.6E+01
1.8E+01
1.8E+OI
2.3E-01
_
2.2E-01
-
| 9.3E+00
2.7E+05
4.2E+04
-
1E-04 |
2.1E-KX)
2.7E+OI
2.6E+02 !
1.8E402
1.8E+02
2.3E+00
_
2.2E-KX)
9.3E+01
2.7E+06
4.2E-f05
_
_
_
Concentrations are given in milligrams per kilogram (mg/kg)
Risk-based RGOs which are less than the current EPCs are indicated with a cell border
RGO not available or not applicable
1 n-Hexane is a surrogate for petrolem hydrocarbons
EPCs Exposure point concentration in soil (Table 3.2)
RGO Remedial goal option
TCR Target cancer risk
THI Target hazard index
Source: Gcraghty and Miller, 1994b
-------
TABLWO
RISK-BASED REMEDIAL GOAL OPTIONS FOR SOIL
BASED ON HYPOTHETICAL FUTURE CHILD RESIDENT EXPOSURE
SITE OT-ll/OU-2, RESIDUAL PESTICIDE DISPOSAL AREA
HOMESTEAD AIR RESERVE BASE, FLORIDA
(Page 1 of 2)
Constituents
Acetone
Bromodichloromethane
2-Butanone
Carbon disulfide
Chloroform
Dibromochloromethane
1 , 1 -Dichloroethene
BNAs
Acenaphthene
Acenaphthylene
Anthracene
Benzo(a)anthracene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Benzo(g,h,i)perylene
Benzo(a)pyrene
Butylbenzylphthalate
Carbazole
Chrysene
Dibenzo(a,h)anthracene
Dibenzofuran
Fluoranthene
Fluorene
Indeno( 1 ,2,3-c,d)pyrene
2-Methylnaphthalene
Naphthalene
Phcnanthrene
Pyrene
EPCs
29
0.65
1.5
0.010
0.68
0.68
0.26
0.37
0.068
0.48
0.85
2.7
1.1
0.63
1.7
0.033
0.40
1.6
0.34
0.53
7.1
0.45
0.69
0.21
0.39
2.1
5.1
Non-Cancer Risk-Based RGOs
THI: | 0.1
6.7E+02
._
2.6E403
5.7E+01
--
3.0E+02
1.6E+02
1.6E+03
-
-
-
1.6E+02
-
-
-
I.6E+02
1.9E+02
1.9E402
-
1.2E+02
7.2E+01
1.6E+02
1.6E+02
1
6.7E+03
2.6E-KM
5.7E402
J
3.0E+03
1.6E+03
1.6E+04
-
-
I.6E+03
-
-
-
.
-
1.6E+03
1.9E+03
1.9E+03
-
1.2E403
7.2E402
1.6E+03
1.6E+03
10 | TCR:
6.7E+04
2.6E+05
5.7E+03
3.0E+04
1.6E-^
1.6E+05
-
-
-
1.6E+04
-
-
-
-
-
1.6E+04
1.9E+04
1.9E-f04
-
1.2E+04
7.2E+03
1.6E+04
1.6E-KM
Cancer Risk-Based RGOs
| 1E-06 :
1.3E+01
2.1E+01
9.4E+00
5.3E-01
-
-
1.2E+00
[ I.2E+00 j
1.2E+00
-
| 1.2E-01 |
-
3.9E+01
I.2E+01
| 1.2E-01 |
_
1.2E+00
-
-
-
IE-OS
1.3E+02
2.1E+02
9.4E+01
5.3E-KX)
-
-
1.2E+01
1.2E401
I.2E+OI
-
1 1.2E-M30 |
-
3.9E+02
1.2E+02
| 1.2E+00
~
_
1.2E+01
-
-
_
-
1E-04 |
I.3E+03
l
2.IE+03
9.4E-H)2
5.3E-H)!
-
-
1.2E+02
1.2E+02
1.2E+02
-
1.2E401
3.9E+03
1.2E+03
1.2E+01
_
1.2E+02
-
-
_
-
-------
TABLE 2-20
RISK-BASED REMEDIAL GOAL OPTIONS FOR SOIL
BASED ON HYPOTHETICAL FUTURE CHILD RESIDENT EXPOSURE
SITE OT-117OU-2, RESIDUAL PESTICIDE DISPOSAL AREA
HOMESTEAD ADR RESERVE BASE, FLORIDA
(Page 2 of 2)
Constituents EPCs
Tffl: |
Pesticides
AJdnn 0.0050
Chlordane 0.033
4,4'-DDD 0.0064
4,4'-DDE 0.0060
4.4-DDT 0.034
Dieldrin 0.0064
Endosulfann 0.0072
Heptachlorepoxide 0.0040
Methoxychlor 0.085'
Metals
Aluminum 5,200
Arsenic 4.6
Cadmium 0.85
Chromium 17
Copper 12
Iron 4,900
Lead 20,000
Manganese 69
Mercury 0.10
Silver 3.4
Vanadium 7.1
Zinc 29
Non-Cancer Risk-Based RGOs
0.1
-
-
-
9.3E+00
-
-
-
-
2.3E+02
-
-
7.9E+02
6.7E-01
3.6E+01
2.1E+01
2.2E+03
1
-
-
-
9.3E+01
-
-
-
2.3E+03
-
-
7.9E+03
6.7E+00
3.6B+02
2.1E+02
2.2E+04
10 | TCR: |
-
-
-
9.3E+02
i
-
I
1
-
2.3E+04
-
7.9E+04
6.7E+01
3.6E+03
2.1E+03
2.2E+05
Cancer Risk-Based RGOs
IE-06
2.3E-02
3.0E-OI
2.4E+00
1.7E+00
1.7E+00
2.5E-02
_
2.7E-02
-
-
| 5.1E-01 1
2.9E+04
4.5E+03
-
-
-
-
. -
1E-05
2.3E-01
3.0E+00
2.4E-^01
1.7E+01
1.7E+01
2.5E-01
_
2.7E-OI
-
| 5.1E+00
2.9E+05
4.5E+04
-
-
-
_
1E-04 |
2.3E+00
3.0E+OI
2.4E+02
1.7E+02
1.7E+02
2.5E+00
_
2.7E+00
-
5.IE+01
2.9E+06
4.5E-KJ5
-
Concentrations are given in milligrams per kilogram (mg/kg)
Risk-based RGOs which are less than the current EPCs are indicated with a cell border
- RGO not available or not applicable
EPCs Exposure point concentration in soil (Table 3.2)
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 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 Site OT-1 l/OU-2 provide little usable or preferred
habitat for terrestrial species. Flightline activity near OT-1 l/OU-2 likely inhibits the
activities of 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. Animals
potentially present in the vicinity of Homestead ARE are more likely to inhabit and utilize
less active-surrounding areas such as Everglades and Biscayne National Parks, located near
the Base. Constituents detected at OT-1 l/OU-2 may represent potential ecotoxicological
effects; however, it is highly unlikely that terrestrial biota would inhabit or frequent the site
due to the Flightline activity and limited natural resources. The potential water hazards to
aquatic life from groundwater contaminants being transported and discharged to surface
water bodies (i.e., the OU-2 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.
2.10 DESCRIPTION OF ALTERNATIVES
The USAF initially considered four alternatives in the Feasibility Study (FS) to address the
soil contamination identified at OU-2. The four alternatives were screened based on the
criteria of effectiveness, implementability, and cost The three most promising alternatives
were carried forward through complete evaluation. These three alternatives were then
evaluated against the nine CERCLA criteria requirements for selecting a remedial 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 effectiveness,
and overall protection of human health and environment A summary of the four alternatives
described in the Feasibility Study are presented below while each is discussed in greater
detail in the FS.
32
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2.10.1 Alternative 1 - No-Action
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. The No-Action Alternative includes two 5-year site
reviews involving literature searches, site walks, interviews, and minimal sampling. The no-
action alternative is protective of human health under current land use conditions, but is
slightly above FDEP criteria for risk (1 x 10"6) for the hypothetical future residential land use
scenario. This alternative does not control exposure to potentially contaminated soil;
however, the contaminants which strongly adsorb to soil particles are considered relatively
immobile and are not expected to migrate off site.
A present worth analysis is used to evaluate expenditures that occur over different time
periods by discounting all future cost to a common base year, usually the current year. This
allows the cost of remedial action alternatives to be compared on the basis of a single figure
representing the amount of money that, if invested in the base year and disbursed as needed,
would be sufficient to cover all costs associated with the remedial action over its planned life.
The present-worth cost of this alternative is estimated at $43,300. This cost consists of two 5
years site reviews with an estimated cost of $29,500 each. The cost of the 5 years site
reviews have been discounted to present value using a 5% discount rate.
2.10.2 Alternative 2 Access and Use Restriction for Soil, Access Restriction for
Groundwater, and Groundwater Monitoring
This alternative includes use and access restrictions for soils in the form of deed restrictions
and/or fencing around the area of concern and the installation of two new groundwater
monitoring wells. These two wells (see Figure 2-11 for proposed well locations), and also
the existing deep and shallow wells will be sampled annually for pesticides, PAHs, and
priority pollutant metals for 5 years to monitor for any future migration of COPCs into the
groundwater. The installation of two new monitoring wells is to ensure protectiveness
through the monitoring of shallow groundwater with respect to potential discharge to the
boundary canal in the event that all areas of contamination have not been identified. This
alternative also includes access restrictions that would prevent placement of a potable well in
the groundwater beneath Site OT-ll/OU-2. Two 5-year site reviews are included which
involve literature searches, site walks, interviews, soil sampling, and a groundwater sampling
review to determine the effectiveness of the remedy. This alternative is protective of human
health and the environment under the current and probable future land use conditions and
33
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5i"~ -4.OCAT4ON "OFi.
Air Fore*
R«Mrv«
Stonga Area
MonBoftng W«l Location
DMp Mentoring WU Location
Sol Boring Location
Proposed Monloitng W«« Location
OrmlnagaOteh
Canal
FtowOfc»cOon
SU Boundary
OpanOnustand
Note: Only 10! Mmpto* eo«>ct«rt fei 1993 */»
nalyzwl lor mMata.
U.S. ARMY CXDRPS OF ENGINEERS
HOMESTEAD ARB
AREA OF CONCERN FOR
SrTEOT-11/OU-2
FIGURE 2-11
-------
relies on institutional controls to prevent exposure for the hypothetical future residential land-
use scenario. This alternative does not actively reduce the toxicity, mobility or volume of the
potential contaminants in the soil, and relies on control measures to prevent access or
exposure to contaminated areas at Site OT-1 l/OU-2
The present-worth cost of this alternative is estimated at $226,400. This cost consists of an
estimated initial capital cost of $68,500, five annual operation and maintenance (O&M)
reviews with an estimated cost of $25,200 each, and two 5 years site reviews with an
estimated cost of $29,500 each. The cost of the annual O&M reviews and the 5 years site
reviews have been discounted to present value using a 5% discount rate.
2.103 Alternative 3 Institutional Controls, Capping, and Groundwater
Monitoring
This alternative consists of the placement of a 2-ft thick soil cap over a 20-ft by 20-ft area to
prevent exposure to soil contaminants. Approximately 250 cubic yards of clean imported fill
material would be required to cap the site. The soil cap, once in place, would be packed,
scarified, and hydroseeded to promote revegitation and reduce erosion. Institutional controls
would be enacted to prevent residential development and child care facilities at the site.
Deed restrictions would be developed and enforced by the current landowner, the U.S. Air
Force. If the base is deactivated and a transfer of ownership occurs, the new landowner
would be responsible for enforcing these restrictions. Monitoring well installation and
sampling as described in Alternative 2 would be performed to determine the effectiveness of
the remedy. This alternative does not actively reduce the toxicity, mobility, or volume of
contaminants in the soil, and relies on control measures to prevent access or exposure to
contamination on site.
The present value of this alternative is estimated at $236,200. This cost consists of an
estimated initial capital cost, ten years of annual operation and maintenance costs, and two
five year site reviews..
This alternative was not carried forward into the detailed analysis phase of the FS because it
is more difficult to implement than Alternative 2 and does not provide increased
effectiveness.
34
-------
2.10.4 Alternative 4 - Excavation, Off-Site Disposal of Soils, Access Restriction for
Groundwater, and Groundwater Monitoring
This alternative consists of excavating the areas with elevated concentrations of lead and
PAHs to levels below the State of Florida Health-Based Soil Target Levels and transporting
the soil to an off-site permitted RCRA landfill for disposal. If required, stabilization of the
soil could be performed either on or off site prior to disposal. Additionally, this alternative
includes the installation of two shallow monitoring wells (see Figure 2-11, proposed well
location) which would be sampled annually for 5 years along with the existing deep and
shallow .wells to monitor for any future migration of COPCs into the groundwater. The
installation of two new monitoring wells is to ensure protectiveness through the monitoring
of shallow groundwater with respect to potential discharge to the boundary canal in the event
that all areas of contamination have not been identified. This alternative also includes access
restriction in the form of site fencing around the perimeter of the 20 acre site and deed
restrictions that would prevent the placement of a potable well in the groundwater beneath
site OT-1 l/OU-2. An estimated 60 cubic yards or 90 tons of material would be excavated for
disposal off-site. Testing of the soil is also included to determine if the material is a RCRA
hazardous waste and/or to determine if it meets land disposal regulations. If the standards are
not met, soils would be stabilized in order to meet the land disposal regulations treatment
standards. If the excavated soils, after adequate testing, are determined to be RCRA
hazardous waste, the contaminated soil will be disposed of at an approved RCRA Subtitle C
facility. Because contaminated soils would be removed from the site, this alternative
permanently reduces risk to base personnel and potential future residents to an acceptable
level and provides adequate protection of the environment
The present-worth cost of this alternative is estimated at $265400*. The present-worth cost
with stabilization of the soil is $289,300*. This cost consists of an estimated initial capital
cost of $150,950'* and five annual O&M reviews with an estimated cost of $25,200 each.
The cost of the annual O&M reviews have been discounted to present value using a 5%
discount rate. *(These costs reflect an increase of $60,000 over the costs given in the FS and
$50,000 over the costs provided in the Proposed Plan. The additional costs represent
$10,000 due to the EPA requirement to include groundwater access restriction and $50,000
to provide for a perimeter fence around the approximate 20 acre site.)
35
-------
2.11 SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES
An evaluation and comparison of the alternatives is presented in Table 2-21. 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:
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
The estimated excess cancer and noncancer risks to humans under current conditions are
within acceptable guidelines set by USEPA. The excess cancer risk for the worst-case
scenario, a future hypothetical resident exposed to soils, is estimated at 3x10"J. The
noncancer risk is estimated at 0.09. The excess cancer risk range considered acceptable by
USEPA is 10 * to 10"6. The noncancer limit considered acceptable by USEPA is 1. Predicted
blood lead level for a hypothetical future child resident was estimated at 3.63 fig/dL, which is
below the USEPA guideline of 10 fig/dL, and indicates a low level of concern for lead
exposure if the site were re-developed for future land use.
All of the alternatives are within the USEPA acceptable risk range of 10"4 to 10"6 under
current and potential future land use conditions but are slightly above the FDEP benchmark
for acceptable risk of 1 x 10"6 based on the site-specific risk assessment performed for Site
OT-1 l/OU-2. However, the no-action alternative and Alternative 2 may not be protective of
the environment. Constituents detected at.Site OT-1 l/OU-2 may represent potential
ecotoxicological effects; however, it is highly unlikely that terrestrial biota would inhabit or
36
-------
TABLW-21
COMPARATIVE ANALYSIS OF FINAL ALTERNATIVES FOR SITE OT-ll/OU-2
RESIDUAL PESTICIDE DISPOSAL AREA
HOMESTEAD AIR RESERVE BASE, FLORIDA
(Page 1 of 4)
Criteria
Alternative 1
No Action
Alternative 2
Access and Use Restriction For
Soil, Access Restriction For
Groundwater, and Groundwater
Monitoring
Alternative 4
Excavation, Off-Site Disposal
of Soils, Access Restriction
For Groundwater, and
Groundwater Monitoring
Overall Protect! veness
Human Health Protection
- Dermal Contact/
Ingestion/Inhalation
Environmental Protection
Compliance with ARARs
Chemical-Specific
Location-Specific
Action-Specific
Other Criteria and Guidance
Only current completed exposure pathway
is that of base worker cutting the grass.
Excess cancer risk is conservatively
estimated at 3x10-7. Potential future
cancer risk may be as high as 3x10-3.
Predicted blood lead level for a
hypothetical child receptor is acceptable at
3.63 Hg/dl.
Potential for constituents detected at Site
OT-11 to cause ecotoxicologlcal effects.
However, unlikely that terrestrial biota
would spend a great deal of time at the
site.
This alternative meets chemical-specific
ARARs
There are no location-specific ARARs
There are no action-specific ARARs
associated with this alternative.
Does not address the TBCs (e.g.. FDEP
soil cleanup guidelines) applicable to soil
contamination at Site OT-11.
Same as Alternative 1.
Same as Alternative 1.
Same as Alternative 1.
Same as Alternative 1.
Same as Alternative 1.
i
Same as Alternative 1.
Permanently reduces risks by removing
contaminants from site.
Permanently reduces potential for
surficial exposure to contaminants.
Same as Alternative 1.
Same as Alternative 1.
LDRs may be applicable. Soil must
meet LDRs prior to disposal.
. Alternative removes contaminants from
Site OT-11.
-------
TABLE 2-21
COMPARATIVE ANALYSIS OF FINAL ALTERNATIVES FOR SITE OT-ll/OU-2
RESIDUAL PESTICIDE DISPOSAL AREA
HOMESTEAD AIR RESERVE BASE, FLORIDA
(Page 2 of 4)
Criteria
Alternative 1
No Action
Alternative 2
Access and Use Restriction For
Soil, Access Restriction For
Groundwater, and Groundwater
Monitoring
Alternative 4
Excavation, Off-Site Disposal
of Soils, Access Restriction
For Groundwater, and
Groundwater Monitoring
Long-Term Effectiving and
Permanence
Magnitude of Residual Risk
Adequacy and Reliability of
Controls
Contamination in soil above FDEP
Health-Based Soil Target Levels.
No controls over contamination. No
reliability.
Same as Alternative 1.
Relies on use restrictions to prevent future
exposure to workers and potential residents.
Need for 5-Year Review
Review would be required to verify
contamination at site is not above health-
based levels of concent.
Same as Alternative 1.
Reduction of Toxicity. Mobility, or
Volume through Treatment
Treatment Process Used None.
Amount Destroyed or Treated None.
Reduction of Toxicity,
Mobility, or Volume
None.
None.
None.
None.
Eliminates residual risk because
contaminants are removed.
Relies on access restrictions to prevent
pouble wells from being placed on
site. Fencing will be placed around the
perimeter to restrict access to vehicle
and foot traffic for unauthorized entry.
The 5 year site review will be required
because of concern that potential
sources of contamination in areas
adjacent to OU-2 may exist since the
area has not been fully characterized.
None
None
Contaminants that cause adverse health
risk removed from site.
-------
TABLE 2-21
COMPARATIVE ANALYSIS OF FINAL ALTERNATIVES FOR SITE OT-M/OU-2
RESIDUAL PESTICIDE DISPOSAL AREA
HOMESTEAD AIR RESERVE BASE, FLORIDA
(Page 3 of 4)
Criteria
Alternative 1
No Action
Alternative 2
Access and Use Restriction For
Soil, Access Restriction For
Groundwater, and Groundwater
Monitoring
Alternative 4
Excavation, Off-Site Disposal
of Soils, Access Restriction
For Groundwater, and
Groundwater Monitoring
Shorl-Term Effectiveness
Community Protection
Worker Protection
Implemenlabilitv
Ability to Construct and
Operate
Flexibility of Action
Ability to Monitor
Effectiveness
No risk to community.
No risk to workers.
Environmental Impacts, None
Time to Complete Action Not applicable
Not applicable.
Not applicable.
None required.
Same as Alternative 1.
Same as Alternative I.
None
Not applicable
Access and use restrictions require
cooperation of the base and local regulatory
agencies. Installation and sampling of
monitoring wells is easily implemented.
Not applicable.
None required.
Same as Alternative I.
Workers could potentially be exposed
to contaminants during excavation.
Protective clothing would reduce
potential risk.
None
Excavation and disposal of soil could
be completed within 6 months.
Excavation and disposal of soils is
easily implemeniable.
The volume and type of soil excavated
is easily changed.
None required.
Ability to Obtain Approvals No approvals necessary.
Same as Alternative I.
Same as Alternative 1.
-------
TABLE 2-21
COMPARATIVE ANALYSIS OF FINAL ALTERNATIVES FOR SITE OT-ll/OU-2
RESIDUAL PESTICIDE DISPOSAL AREA
HOMESTEAD AIR RESERVE BASE, FLORIDA
(Page 4 of 4)
Criteria
Alternative 1
No Action
Alternative 2
.Access and Use Restriction For
Soil, Access Restriction For
Groundwater, and Groundwater
Monitoring
Alternative 4 '
Excavation, Off-Site Disposal
of Soils, Access Restriction
For Groundwater, and
Groundwater Monitoring
Availability of Services,
Equipment, and Materials
Capital Cost
Annual O&M Costs
Five-Year O&M Costs
Present Worth
No special services, equipment, or
materials required
Availability of Technologies None required
$0
$0
$29,500 (every 5 years)
$43,300
Conventional drilling equipment and
contractors readily available.
None required.
$68.500
$25.200 (for 5 years) and
$29,500 (every 5 years)
$226.400
Conventional excavation and
transportation equipment and
contractors readily available.
Stabilization easily implementable, if
required
$150.950* to $174,750*
$25.200 (for 5 years)
$265,500* to $289.300*
Notes: 'Including perimeter fencing of the entire 20 acre site.
-------
frequent the site. Alternative 4 is protective of the environment because it reduces potential
for surficial exposure to contaminants by removal of soils with elevated concentrations of
PAHs and lead concentrations exceeding FDEP Health-Based Target Levels.
2.11.2 Compliance with ARARs
All alternatives meet ARARs. The chemicals detected in groundwater and surface water are
below federal and state promulgated standards and there are no ARARs for soils and
sediments. Alternative 4, only, meets TBC guidelines for soil cleanup levels (FDEP Health-
Based Soil Target Levels and DERM Clean Soil Criteria).
2.11.3 Long-term Effectiveness and Permanence
Alternatives 1 and 2 do not provide permanent solutions to the remedial action objectives.
Alternative 4 permanently reduces the risks from both inhalation and ingestion by removing
the contaminated soils from Site OT-11 /OU-2.
2.11.4 Reduction of Mobility, Toxkity, or Volume Through Treatment
Alternatives 1 and 2 do not involve treatment. Alternative 4 reduces the mobility of
contaminants but does not reduce the volume or toxicity of contaminants. Alternative 4 will
involve treatment if excavated soil is determined to be a RCRA hazardous waste.
2.11.5 Short-Term Effectiveness
Alternatives 1 and 2 are not expected to pose significant risk to the community or workers
during implementation. Under Alternative 4, excavation and disposal might cause some risk
to the workers but protection measures can be easily implemented. There are no anticipated
adverse environmental impacts from any of the alternatives.
37
-------
2.11.6 Implementability
Alternatives 1,2, and 4 are easily implementable.
2.11.7 Cost
Alternative 1 provides protection to human health and the environment and has a 10-year
present worth of $43,300. Alternative 2 uses institutional controls to limit access to the
contaminated soils and would cost approximately $226,400. Alternative 4 eliminates all
risks at the site associated with the contaminated soils and costs approximately $265,500 if
stabilization is not required and $289,300 if stabilization is required.
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 4 - Excavation, Off-Site Disposal of
Soils, Access Restriction for Groundwater, Site Fencing, and Groundwater Monitoring is the
most appropriate course of action for Site OT-1 l/OU-2.
This alternative is protective of human health and the environment under the current and
unlimited future land use conditions because it removes the contaminated soils from the site.
The groundwater will be monitored annually for 5 years to monitor any future migration of
contaminants in areas within and adjacent to OU-2 that may not have been fully
characterized, such as the southern vegetation and fill areas. After the five year monitoring
period, EPA, FDEP, and the USAF will evaluate the effectiveness of the remedy and the
need for continued groundwater access restrictions. This alternative would be protective,
cost effective, and complies with all Federal and State ARARs. The selected remedy has
been accepted by the State and community concerns have been addressed in the
Responsiveness Summary of this ROD.
A five year review will be conducted to determine whether the remedy remains protective of
human health and the environment and to evaluate the need for continued groundwater
access restrictions.
38
-------
2.13 STATUTORY DETERMINATIONS
Under its legal authorities, EPA's primary responsibility at Superfund sites is to undertake
remedial actions that achieve adequate protection of human health and the environment. The
selected remedy reduces and controls the existing risk from exposure to soil by excavation of
contaminated soils. The selected remedy reduces and controls potential risk from exposure
to groundwater by use of access restrictions to groundwater. In addition, Section 121 of
CERCLA establishes several other statutory requirements and preferences. These specify
that when complete, the selected remedial action for this site must comply with applicable or
relevant and appropriate environmental standards established under Federal and State
environmental laws unless statutory waiver is justified. Since the applicable MCLs are
already being met, the selected remedy satisfies all Federal and State ARARs. The selected
remedy also must be cost-effective and utilize permanent solutions and alternative treatment
technologies or resource recovery technologies to the maximum extent practicable. The
selected remedy has been determined to be cost-effective and utilizes permanent solutions by
excavation of contaminated soils. Finally, the statute includes a preference for remedies that
permanently and significantly reduce the volume, toxicity, or mobility of hazardous wastes as
their principal element. The selected remedy will only satisfy this preference in the event
that the excavated soils need treatment pursuant to Subtitle C of RCRA.
2.14 DOCUMENTATION OF SIGNIFICANT CHANGES
The PP was released for public comment on September 18, 1995. The PP identified
Alternative 4 - Excavation, Off-Site Disposal of Soils, Access Restriction for Groundwater,
and Groundwater Monitoring as the preferred alternative for remedial action at Site OT-
ll/OU-2.
The selected alternative has been modified from the March 1995 Feasibility Study due to the
added EPA requirement to include groundwater access restriction to the selected alternative.
This modification increased the cost of the alternative by $10,000. This change was
reflected in the September 1995 Proposed Plan.
39
-------
Perimeter Fencing, as presented in this ROD for the selected alternative, was added based on
public concerns expressed during the public meeting. Site fencing was not included as part
of Alternative 4 in the March Feasibility Study or the September Proposed Plan. Inclusion of
site fencing increased the cost of the selected alternative by $50,000.
Responses to comments received during the September-October 1995 public comment period
are presented in the attached Responsiveness Summary.
40
-------
Homestead Air Reserve Base, Florida
Operable Unit No. 2
Site OT-11, Residual Pesticide Disposal Area
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. 2, 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 OT-1 l/OU-2 were released to the public in July 1994 and September
1995, 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.
The public comment period was held from September 18, 1995 to November 2, 1995, as part
of the community relations plan of Operable Unit 2. Additionally; a public meeting was held
on Monday, September 18, 1995, at 7:00 PM at South Dade High School. A public notice
was published on September 6, 1995 in the South Dade News Leader and on September 7,
1995 in the Miami Herald to announce the .purpose, location, date, and time of the public
meeting. At this meeting, the USAF, in coordination with EPA Region IV, FDEP, and
DERM discussed the investigation, results of the Baseline Risk Assessment, and Preferred
Alternative described in the Proposed Plan.
Summary of Public Comments Received During the Public Comment Period
Comments received during the September 18, 1995 public meeting and the September 18
through November 3, 1995 public comment period are summarized on the following pages.
-------
Originator: South Florida Water Management District
Comment: Although we do not have any specific comments on the clean-up of Operable
Unit 2, the Residual Pesticide Disposal Area, we remain interested in the activities on the
Homestead Air Reserve Base and any associated Base Reuse Plans.
In General, these concerns remain:
1. Any contaminated groundwater or soil clean-up plans must be considered when
proposing revisions in surface water management facilities or changes in land use in
general.
2. The relationship between all entities with an interest in long term operation and
maintenance of the existing and proposed water management system must be
established.
3. Continued coordination with Metro-Dade County, FDEP, and the District on specific
construction activities as plans are developed.
Response: The USAF. in conjunction with the Base Closure Team (BCT) will continue to
take the steps necessary to insure protectiveness to human health and the environment. The
USAF understands the concerns of the community and many of the interested parties
associated with the redevelopment of the base, they will continue to act under their current
policy of stewardship and good housekeeping. The USAF will continue to coordinate with
the BCT and solicit comments and concerns regarding cleanup and redevelopment of the
base. These comments are carefully reviewed by the BCT, comprised of representatives
from the USEPA, FDEP. DERM, and the USAGE. The USAF encourages public input
through organizations such as the Restoration Advisory Board (RAB) and public meetings.
Originator: L. Anthony
Comment: Reference Proposed Plan for Restoration of Operable Unit 2, Site OT-11 as
part of the Installation Restoration Program at Homestead Air Reserve Base by the
Department of the Air Force.
By separate comments, dated September 13, 1995,1, Leonard S. Anthony, 14820 Naranja
Lakes Boulevard, Homestead, Florida, submitted comments concerning the Proposed Plan.
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Subsequent to that submission, I have had the opportunity with the assistance of Base staff,
Mr. Robert Courtright, Remedial Project Manager and Judith C. Gretsch, W.P.I. Inc., to visit
the project site. Although not traversing the entire site on foot, I was able to determine that
area undocumented with test points, are indeed wooded and overgrown with vegetation.
They are essentially overgrown to the extent that they were inaccessible by vehicle or on foot
and therefore revealed no added information.
Ms. Gretsch also made available certain documentation.
One document, Engineering-Science, August 1983, Installation Restoration Program, Phase
I-Records Search is Atlanta Georgia AR/1R3 395, on page 4-11 states in part, 'The practice
was to spray the waste over a wide area, after which chlorine bleach and ammonia were
applied as neutralizing agents." There is no indication in this paragraph that this wide area
was confined to roadways or pathways but rather a "wide area" however undefined.
Page 5-6 of this same document states, "The disposal practice involved spraying the wastes
on the ground over a twenty acre area, followed by applications of chlorine bleach and
ammonia to help break down the chemicals. While the wastes were not applied in
concentrated form on a localized area, the extremely permeable nature of the surface soils
and underlying rock in the area make the site a potential source of groundwater
contamination." This reference certainly discounts any localized patterns of disposal,
emphasizing that the disposal was over twenty acres of land, possibly.
Page 2-18 of "Science Application International Corporation, March 1986, Installation
Restoration Program Phase n - Confirmation/Quantification Stage 1, Final Report SAIC:
McLean, VA AR/IR #466 states in part, "Waste pesticides....were disposed of in an open
area..... The disposal practice involved pouring and spraying the wastes on the ground over a
20-acre area,...." Here it is noted that the area was "open" and a 20-acre area was used. This
disposal period covered five (5) years from 1977 to 1982. There is no mention of pattern
disposal, only that the open 20 acres were used.
The Draft Final Report (April 1994), "Remedial Investigation Report for Site OT-11,
Residual Pesticide Disposal Area, Volume 1 of XIV, AR/IR #1326 HAFB, FL, "on page
XVn of the executive summary notes that the northern portion of the site was significantly
altered, physically, since the last investigation. The vegetation and rubble fill had been
removed and a large mound of what appeared-to be excess road (asphaltic) and fill dirt was
present" The paragraph later notes that the PAH's and high levels of lead were detected in
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soil samples - possibly due to these rubble piles. It is unknown when the last investigation
referred to was performed, but there is an obvious change of the topography of the site over
time from earlier 1983 and 1986 documented on page 1-5 of this same document, and 1993
(CERCLA Field Investigation Time). If the site were totally accessible and used in the 1977-
1982 period and subsequent piles of rubble were stored there and moved, there may still be
some residuals still there in the overgrown and wooded areas, possibly under the piles where
no test points have been documented. Given that high levels of lead were found in the north
area, there may be a different type contamination here than just pesticides of a level to
warrant further investigation.
The site history of documents "Montgomery Watson, March 1995, Feasibility
study for OT-11 - Residual Pesticide Disposal Area, Final Report, Montgomery Watson;
Walnut Creek CA AR/IR #1342, further notes that intermittent use of the site for the storage
of asphaltic materials, although generally confined to the northern area.
The essential concern is that there is a clear lack of documentation at testpoints randomly
conducted throughout the site.
1. There may be contaminants of concern under the debris piles given the changing
conditions on the site over time.
2. Remediation of the contaminants in the soil has been selectively addressed, that is
identified and scheduled for removal etc. The entire twenty acre site is not included
nor has testing been accomplished.
3. If this alternative is accepted and implemented, there can be no assurance of what lies
under/in the untested areas. Yet remediation will have been assumed to have been
accomplished and the entire site, all twenty acres will have been assumed completed.
4. The suggested site remediation alternative includes the provision of wells for
continued multi-year testing. However, the hallmark contaminant is for now water
soluble pesticides that are bound in the soil. The use of wells to monitor future
pesticide contamination seems inconsistent. Other contaminants such as metals,
BNAs (PAHs), will not necessarily be detected in those well points because they may
be trapped hi the piles.
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Response: The southern vegetation and fill areas were generated as a result of
construction and demolition debris from the construction of the expanded runway in the early
1950s. Residual pesticide disposal occurred from 1972 to 1982. As the Base began
investigating potential areas of concern, activities associated with the Residual Pesticides
Disposal Area were reviewed. During the IRP Phase II and Phase IV investigations,
emphasis focused on soil and groundwater in the northern portion of the site. Then during
the 1991 remedial investigation, the area was expanded to include the southern fill/vegetation
areas. The perimeters of the fill/vegetation were sampled with the presumption that pesticide
disposal would have more readily occurred along the roadways which surround these areas
because they were more readily accessible. Sediment and surface water samples were
collected from the canals adjacent to the fill/vegetation areas to assess potential impacts from
runoff and seepage into the adjacent canals. Soil, sediment, and surface water samples
collected during this event were analyzed for pesticide. The results from these analyses
indicate that there were no significant impact to soil, surface water, or sediments as a result
of pesticide disposal operations. In 1993, a Boundary Canal Remedial Investigation was
completed which included the collection of additional sediment and surface water samples
for an expanded parameters list in the canals adjacent to the site. The results from these
analysis also indicated that there were no significant impacts to the canals as a result of past
operations.
Due to the absence of significant pesticide contamination around the southern fill/vegetation
area, the investigations returned to the north were the positive detections were observed. The
1993 expanded remedial investigation for this site included the collection of groundwater,
soil, sediment, and surface water with an expanded perimeter list. The results from this
investigation reported elevated levels of lead and PAH compounds. These findings are
reported to be associated with the rubble piles. The sampling and analyses performed to date
do not indicate impacts as a result of residual pesticide disposal activities. However, because
the USAF recognizes the potential for impact to 'the site through leaching of COPCs, annual
monitoring will be conducted followed by a 5-year site review. The annual groundwater
monitoring will consist of analyzing groundwater from the existing monitoring wells plus
two new wells. The collected samples will be analyzed for parameters consistent with the
potential site contaminants and will include pesticides, PAHs, and priority pollutant metals.
Originator: G. Sweitzer
Comment: I have lingering doubts concerning the "Operable Unit 2 - Site OT-11
proposed plan." The "rubble piles" found in the area should be more closely examined to
determine IF pesticide containers are hidden beneath the obvious concrete and asphalt debris.
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These containers MAY NOT HAVE LEAKED as of the studies date. In respect I echo the
statement made by Mr. Len Anthony. The effort should be made to dissect at least some of
these rubble piles and determine if a threat exists. Failure to do so, despite contrary
indications of contamination (wells etc.) will leave doubt in the publics mind that enough
was done to make sure no threat exists.
Response: As was discovered during the investigation of this site, the southern rubble piles
were generated in the early 1950's during the expansion of the runway, approximately 20
years prior to the area being utilized as a residual pesticide disposal area. Residual pesticide
disposal began in this area in 1972. Once the area was identified as a potential source of
contamination, it was systematically investigated to determine the nature and extent of
potential contaminants. This approach included a site review, record search, and multiple
multi-media sampling and analysis events. Results of these efforts indicated the absence of
significant pesticide contamination around the southern rubble piles. Evaluation of the site
with regard to risks to human health and the environment indicate the only unacceptable risk
would be to a hypothetical future adult and child resident exposed to site soils. These levels
are due primarily to the levels of lead and PAH compounds. The selected alternative was
chosen because it was determined to be protective to human health and the environment The
USAF, in conjunction with the USEPA and the FDEP will utilize the annual groundwater
monitoring information to evaluate the effectiveness of the remedy. Should the conditions
change, the USAF will take the steps necessary to insure protectiveness to human health and
the environment.
Public Comment Summary
The United States Air Force has reviewed and analyzed all of the public comments, and has
elected to proceed with the Selected Remedial Alternative outlined within the Feasibility
Study and as announced with the Public Notice Proposed Plan. -
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Homestead Air Reserve Base, Florida
Operable Unit No. 2
Site OT-11, Residual Pesticide Disposal Area
Declaration for the Record of Decision
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DECLARATION STATEMENT
FOR THE
RECORD OF DECISION FOR OPERABLE UNIT NO. 2
SITE NAME AND LOCATION
Homestead Air Reserve Base
Homestead, Dade County, Florida
Operable Unit No. 2 - Site OT-11
Residua] Pesticide Disposal Area (Former Site P-3)
STATEMENT OF BASIS AND PURPOSE
This decision document presents the selected remedial action for the Residual Pesticide
Disposal Area (Site OT-11), Operable Unit No. 2 (OU-2), 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 OT-11 /OU-2.
The selected alternative for OU-2 is excavation, off-site disposal of soils, installation of
perimeter fence for access restriction, institutional controls for groundwatcr restrictions, and
monitoring for any future migration of compounds of potential concern (COPC) into the
groundwater. 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-
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DESCRIPTION OF THE SELECTED REMEDY
The operable unit represents the only unit for the site. This response action addresses the
principal threat at the site by removing contaminated soils. It also requires access restriction,
deed restriction for groundwater use, and groundwater monitoring.
The major components of the selected remedy include:
Excavation of approximately 60 cubic yards of contaminated soil. The soil is slated ^
for disposal at a RCRA permitted facility. Based on testing of the soil, it may require o '
3-°-
treatment to comply with requirements of Subtitle C of RCRA such as land disposal 0^
restrictions. ^
Installation of two shallow monitoring wells and annual groundwater monitoring for
5 years. The groundwater samples will be analyzed for pesticides, PAHs, and priority
pollutant metals.
Institutional controls to restrict the placement of potable water wells into the
groundwater beneath the site. ^'c' Hc"*^":
_^-v~- "!' *'-.
Five year review to determine whether the remedy remains protective of human
health and the environment and to evaluate the need for continued groundwater
access restrictions.
Installation of a perimeter fence to restrict site access (vehicular and foot traffic). -^
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, and satisfies the statutory preference for remedies that
employ treatment that reduces toxicity, mobility, or volume as a principal element, only ifthe
excavated soils need treatment pursuant to Subtitle C of RCRA.- > -
-u-
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Although this remedy will reduce the concentrations of hazardous substances, pollutants, or
other contaminants remaining on site to below Health-Based Levels, a review of the remedial
action will be conducted 5 years after its commencement. The 5 year review is conducted
because there is concern that potential sources of contamination in areas adjacent to OU-2
may exist since the area has not been fully characterized. -.
UNITED STATES AIR FORCE
HOMESTEAD AIR RESERVE BASE
By: Date:.
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RESPONSE TO COMMENTS
RECORD OF DECISION
~ OPERABLE UNIT NO. 2 SITE OT-11
RESIDUAL PESTICIDE DISPOSAL AREA
HOMESTEAD AIR RESERVE BASE, FLORIDA
The following are written responses to comments from Mr. Earl L. Bozeman. Jr. of the USEPA,
received via fax on AprilJS. 1996 regarding review of the Draft Final Record of Decision for
Operable Unit No. 2 Site OT-11, Residual Pesticide Disposal Area at Homestead ARE, FL.
Ref. No.
Item A/E
No.
Comment/Response
Page ii,
First Bullet
1
Comment: Add the sentence "Based on testing of the soil, it
may require treatment to comply with requirements of Subtitle
CofRCRA such as land disposal restrictions."
[A] Response: The text change has been made as requested.
Page ii,
Second Bullet
Comment: Please indicate the parameters for which the
groundwater will be monitored.
[A] Response: The text has been modified to include the
groundwater sampling parameters.
Page ii,
Third Bullet
Comment: Please insert the words "Institutional controls to"
at the beginning of this sentence.
[A] Response: The text change has been made as requested.
Page ii,
Fourth Bullet
Comment: Change the word "site" to' "remedy".
[A] Response: The text change has been made as requested.
Page ii,
First Paragraph
of Statutory
Determinations
Comment: Add the phrase ".only if the excavated soils need
treatment pursuant to Subtitle C of RCRA." to the last sentence
of this paragraph.
OT-11/ROD/BOZEMAN
April 1996
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Ref. No.
Item A/E
No.
Comment/Response
[A] Response: The text change has been made as requested.
Page ii,
Last Paragraph
Comment: Change the first part of the sentence to read
"Although this remedy will reduce the concentrations of
hazardous substances, pollutants, or other contaminants
remaining on site to below health-based levels, a review of the
remedial action will be conducted 5 years after its
commencement" Also, add the following sentence to this
paragraph: "The 5 year review is conducted because there is
concern that potential sources of contamination in areas adjacent
to OU-2 may exist since the area has not been fully
characterized."
[A] Response: The text change has been made as requested.
Page 10,
First Full
Paragraph,
Second Sentence
Comment: Please indicate if the levels of organochlorine
pesticides detected in 5 of the 6 soil samples were above or
below health-based benchmarks. In the fourth sentence of this
paragraph, insert "a" before "high", change "affinities" to
"affinity", insert "an" before "extremely" and change
"solubility's" to "solubility".
[A] Response: Text has been added to indicate these pesticide
concentrations were below the State of Florida Health-Based
Soil Target Levels. Additional text changes have been made as
requested.
Page 11,
Second Full
Paragraph
Page 14,
Last Paragraph,
Second Sentence
8 Comment: Please indicate if the concentrations of
organochlorine pesticides detected in soil samples during the
1988 investigation were above or below health-based
benchmarks.
[A] Response: Text has been added to indicate these pesticide
concentrations were below the State of Florida Health-Based
Soil Target Levels
9 Comment: Please define the acronym "bgs" if not previously
defined in the text
OT-11/ROD/BOZEMAN
April 1996
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Ref. No.
Page 15,
Last Paragraph
Item
No.
A/E
Comment/Response
[A ] Response: The acronym "bgs " has been defined in the text as
requested.
10
[A]
Comment: Please indicate if BNAs detected in soil samples
were above or below health-based benchmarks. Also, in the
last line on this page, please indicate a reference point for the
"...elevated concentrations of total PAHs ..." (i.e.,
background, health -based benchmarks, etc.).
Response: Text has been added to indicate which BNA
detection exceed the State of Florida Health-Based Soil Target
Levels. The term elevated as it refers to concentration of total
PAHs in samples P3-SL-0027-1, P3-SL-0028-1, and P3-SL-
0030-1 has been removed from the text.
Page 27, 11
Second Full
Paragraph,
Second Sentence
Page 28, 12
Second Full
Paragraph,
Fourth Sentence
Comment: Insert "some" before "contaminants" and delete
"of concern".
[A] Response: The text changes have been made as requested.
Comment: Change "of to "or" between EPA and FDEP.
Same page, last paragraph, first sentence, dose is misspelled.
[A] Response: These typographical errors have been corrected.
Page 30, 13
Last Paragraph
of Section 2.9.6
Comment: Why are RGOs presented for the HQ level of
10? Also, the first sentence pf this paragraph is confusing.
Please reword.
[A] Response: The risk assessment was prepared by another
A.E., however previous guidance evaluated the HQ an order
of magnitude above and below 1, i.e., 0.1, and 10. Current
guidance calls for RGOs for the HQ at 0.1,1, and 3.
Page 32,
Section 2.10.1,
First Paragraph,
Third Sentence
14
Comment: This statement is contradicted by the statement
made in the first sentence of the first full paragraph on page
36.
OT-11/ROD/BOZEMAN
April 1996
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Ref. No.
Page 34,
Section 2.10.1,
First Sentence
Page 36,
First Paragraph,
First Sentence
Item A/E
No".'
Comment/Response
[AJ Response: The No Action alternative is below the USEPA
range oflO4 to 1Q* but above the FDEP benchmark of 1O* for
the future land use scenario. The text on page 36 has been
revised.
15 Comment: Reference is made to excavation of areas with
elevated concentrations of PAHs and lead to " ...levels deemed
protective to FDEP ...". Please indicate the levels. In the
same paragraph, seventh sentence, insert "is a RCRA
hazardous waste and/or to determine if it" between "material"
and "meets". In the same paragraph, page 35, first line,
change "eliminates" to "reduces" and insert "to an acceptable
level" between "residents" and "and".
[A] Response: Reference has been made to the State of Florida
Health-Based Soil Target Levels. The remaining text changes
have been made as specified.
16 Comment: See comment 14.
[A] Response: See Response to comment No. 14.
Page 36,
Section 2.11.4
17 Comment: Please insert "Alternative 4 will involve treatment
if excavated soil is determined to be a RCRA hazardous waste"
at the end of this Section.
[A] Response: The text change has been made as requested.
Page 37,
Last Paragraph,
Second Sentence
18 Comment: Please indicate from where future migration of
contaminants may occur.
[A] Response: Additional text has been provided consistent with
the information presented in comment No. 6.
OT-11/ROD/BOZEMAN
Apnl 1996
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Ref. No.
Item A/E
No.
Comment/Response
Page 38,
Last Paragraph of
Section 2.12
19
[A]
Comment: It is stated that the selected remedy includes a
five year review of the site, however, on the second page of
Table 2-12 under Alternative 4, it is stated that the five year
review is not required. Please clarify.
Response: Table 2-27 has been revised to indicate that "the
5 year site review will be required because of concern that
potential sources of contamination in areas adjacent to OU-2
may exist since the area has not been fully characterized.
Page 38,
Section 2.13
20 Comment: Insert "Since the applicable MCLs are already
being met,' at the beginning of the sixth sentence. In the
next to last sentence of this Section, delete "that employ
treatment". Also, change the last sentence of this Section to
read "The selected remedy will only satisfy this preference in
the event that the excavated soils need treatment pursuant to
Subtitle C of RCRA."
Table 2-21,
Page 2
Table 2-21,
Page 4
[A] Response: The text changes have been made as requested.
21 Comment: Under Alternative 4, across from Treatment
Process Used and Amount Destroyed or Treated, please
change the entries to "None", since off site disposal is not
the same as treatment
[A] Response: The text changes have been made as requested.
22 Comment: The cost information for all three alternatives in
this table as well as in the text on pages 32, 33, and 35 is
very confusing. Please explain in greater detail in the text
and ensure the accuracy of the computations in the table.
[A] Response: The cost information has been developed in
accordance with "Remedial Action Costing Procedures
Manual", USEPA, 1985. Additional information has been
provided which discusses the fact that future expenditures,
such as five year site reviews and operation and maintenance
costs have been discounted 5 percent over the specified life
of the alternative in order to determine the present day cost
for performance of the alternative.
OT-11/ROD/BOZEMAN
April 1996
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