United States
Environmental Protection
Agency
Office of '
Emergency and
Remedial Response
March 1985
Superfund
Record of Decision:
Varsol Spill Site, FL
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VARSOL SPILL SITE, DADE mUNI'Y, FL
Record of Decision
Abstract
The Biscayne Aquifer is the sole source of drinking water for
three million residents of Southeast Florida. Three Biscayne Aquifer
hazardous waste sites on the EPA National Priorities List were addressed
as one management unit for the remedial investigation and feasibility
study (RI/FS): 1) Varsol Spill Site (Miami International Airport),
2) Miami Drum Site, and 3) Northwest 58th Street Landfill. The Varsol
Spill Site is located in the northeast section of Miami International
Airport (MIA). Industrial operations associated with a typical ccmnercial
airport have resulted in hydrocarbon contamination of surface and ground
waters in the vicinity of MIA. Since 1966 there have been approximately
15 hydrocarbon spills and leaks totalling approximately 2 million gallons,
including the loss of an estimated 1.5 million gallons of varsol. In
1970, an unknown arrount of jet fuel was spilled into a drainage canal
on-site. In April of 1981, construction activities revealed a thick
hydrocarbon layer floating on the water table in an excavated trench.
One responsible party installed 54 shallow observation wells. Sampling
results showed that the hydrocarbon layer diminished with time. In
another area, Dade County installed 43 rronitoring wells to determine
the extent and rragnitude of jet fuel spilled. Recovery operations
for this jet fuel are currently underway.
The remedial investigation of the site showed no trace of varsol
in and around the airport at this particular time, thus the reccmnended
alternative for this site is no action. Several factors probably con-
tributed to the dissipation of the hydrocarbon layer in the aquifer.
For example, sare of the solvent was recovered, biodegradation is
believed to have taken place, and the hydrology of the area indicates
that sane of the solvent contributed to and became part of the "background"
contamination in the aquifer. A further investigation of the dissipation
of the hydrocarbon layer will be conducted. This will be addressed and
the results will be presented in a separate roD (Phase V) as part of
the remedy for the three sites referred to as the Biscayne Aquifer
Superfund Site.
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.
Record of Decision
Remedial Alternative Selection
>
SITE:
.~
Varsol Spill Site, ,Dade County, Florida
DOCUMENTS REVIEWED
I am basing my decision on the following documents describing
the analysis of cost-effectiveness of remedial alternatives for
the Varsol Spill Site:
Evaluation of the Clean-Up Activities
Undertaken at the Miami Drum Services
Waste Site, Dade County, Florida,
September 1, 1982
Already
Hazardous
Phase I--Compilation and Evaluation of Data
for th~ Protection of the Biscayne Aquifer
and Environment in North Dade County, 'Florida,
October 15, 1982
Remedial Investigation for Miami Drum Services
Site, Florida, Florida Department of Environmental
Regulation, Tallahassee, Florida 32301, ,
November 1983
Phase II--Sampling, Analytical, and Investigative
Program for the Protection of the Biscayne Aquifer
and Environment in North Dade County, Florida,
February 1984
Phase III---Feasibility of Remedial Actions for
the Protection of the Biscayne Aquifer in Dade
County, Florida, November 1984
Record of Decision Summary of Remedial Alt,ernative
Selection, Biscayne Aquifer Sites, Dade County, Florida
~
Background
Phase I: Varsol Spill Site
Responsiveness Summary
DESCRIPTION OF SELECTED REMEDY
In view of the fact that no trace of the var$ol was found at
this time in and around the airport, the recommended alternative
for this site is no action.
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Although large concentrations of spilled jet-A fuel were
found in the groundwater near Concourse E of the airport,
CERCLA (Superfund) does not address jet fuel spills. However,
recovery of the fuel should continue and the contaminated
groundwater there shou~d be be treated in accordance with Dade
County regulat,ions. --- ,
FUTURE ACTIONS
While no varsol was found in and around the airport, the
spill did occur. Several factors could contribute to the fact
that no varsol is detectable at this time; some of the solvent
was recovered. Biodegradation is believed to have destroyed
some more, but the hydrology of the aquifer system strongly
suggests that some of the solvent contributed to and became a
part of the "background" contamination in the aquifer. This
"background" contamination will be addressed in a separate
Record of Decision (Phase V) as part of the remedy for the three
sites referred to as the Biscayne Aquifer Superfund Sites.
DECLARATIONS
Consistent with the Comprehensive Environmental Response,
Compensation, and Liability Act of 1980 (CERCLA), and the
National Contingency Plan (40 CFR Part 300), I have determined
that the no action alternative is a cost effective remedy and,
provides adequate protection of public health, welfare and the
environment. The State of Florida has been consulted and agrees
with the approved remedy.
I have also determined that the action being taken is
appropriate when balanced against the availability of Trust
Fund monies for use at other sites.
7/;" '1/ '65 .
Patel
cc:
J. Silva, WD
J. Finger, ESD
H. Zeller, OPM
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~ECORD OF DECISION
SUMMARY OF'-REMEDIAL ALTERNATIVE SELECTION
BISCAYNE AQUIFER SITES, DADE COUNTY, FLORIDA
BACKGROUND
INTRODUCTION
Three sites proposed for the National Priorities List in
October 1981 are located in northwest Dade County, Florida.
After consulting with the State and County, EPA decided to
address these sites as a single management unit for the
performance of the RI/FS. A major reason for this decision
is that all three sites affect the same general area of the
Biscayne Aquifer. The agencies recognized that the effects
of these sites on the aquifer could be interrelated and that
some of the probl~ms believed to exist would not be solely
attributable to an individual site. This management scheme
worked well for the RI/FS and is also appropriate for the
remedy.
A package of five Records of Decision (RODs) that address
the three sites is planned. One ROD was signed on
September 13, 1982, for the Miami Drum source control.
The second ROD (Varsol) is included herein. This ROD
package will be completed in phases with the final ROD
(Phase IV) planned for fall 1985. In general, the RODs are
as follows:
Phase I:
Varsol Spill Site--irnrnediate area soil and
groundwater
-,
Phase II:
Miami Drum--irnrnediate area groundwate+
Phase IIa:
Miami Drum--source control (soils and
encountered groundwater), completed
September 1982
Phase III:
...
58th Street Landfill--irnrnediate area soil,
surface and groundwater
Phase IV:'
Groundwater in three-site area
SITE LOCATION AND DESCRIPTION
The Biscayne Aquifer is the sole source of drinking water
for three million residents of southeast Florida. Three
Biscayne Aquifer hazardous waste sites on the EPA National
Priorities List were addressed as one management unit for
remedial investigation and feasibility study: (1) Varsol
Spill Site (Miami International Airport), (2) Miami Drum
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Site, and (3) Northwest 58th Street Landfill. These sites
are located close to each other in north Dade County,
Florida. The study area including these sites is defined in
Figure 1. Locations of these sites and public well fields
as well as private wells within the study area are shown in
Figure 2. The topography in the study area is flat,
approximately 5 feet above sea level.
The Varsol Spill Site is located in the northeast section of
Miami International Airport (MIA). The airport is located
less than one-half mile south of the lower Miami Springs
municipal well field. The Miami Canal runs adjacent to the
northeast corner of the airport, the Tamiami Canal runs
immediately south of the airport, and two other canals are
located near the western edge of the airport.
Miami Drum Services was an inactive drum recycling facility
located west of Miami Springs at 7049 N,W. 70th Street in
Miami. The dimensions of this site are 242 feet
(north-south axis) by 230 feet (east-west axis), and it is
located in a predominantly industrial area. The FEC Canal
is located about one quarter of a mile east of the Miami
Drum Site, and the Miami Canal is located less than one mile
northeast of the site. The Medley well field is located
approximately 750 feet west of this site, while the Miami
Springs and Preston well fields are located about 5,000 feet
southeast of the site.
The Northwest 58th Street Landfill consists of a
ohe-square-mile area near the western perimeters of the Town
of Medley and the City of Miami Springs. Present
development adjacent to this landfill site consists of
industrial uses to the south (Northwest 58th Street) and
east (Northwest 87th Avenue), a rock, pit operation to the
north (Northwest 74th Street), and undeveloped land to the
west (Northwest 97th Avenue). A new resource recovery plant
is located directly west of, and adjacent to, the landfill.
The Medley and Miami Springs municipal well fields are
approximately one and one-half miles and two and one-half
miles dcwngradient from the eastern edge of the landfill,
respectively. ~
"
The average annual rainfall over the study area lS
approximately 60 inches, of which as much as 80 percent
falls during the rainy season (June to September). Parts of
the study area are inundated intermittently during the rainy
season, and swampy conditions persist for several weeks each
year, mainly due to rising water table. The maJor drainage
systems of the area are the Miami and Tamiarni Canals
draining into the Biscayne Bay. The secondary drainage
systems include the 58th Street, Dressel, and 25th Street
Canals. The water table beneath the study area is located
approximately 2 to 3 feet below the natural land surface.
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The Biscayne Aquifer, which is a highly permeable,
wedge-shaped, unconfined shallow aquifer composed of .
limestone and sandstone, underlies the study area. The top
of the aquifer is near the natural ground surface, and its
base is approximately 60 feet below ground surface in the
Northwest well field 'area and approximately 105 feet below
. ground surface in the Miami International Airport area.
Figure 3 shows. the geologic section of the Biscayne Aquifer
in the Miami Springs/Preston well field area. In general,
this aquifer is divisible, from top to bottom, into three
distinct water-producing zones, each zone being 15 to 20
feet thick. These zones are separated by generally dense,
silty to sandy limestones and well-cemented quartz sands
that act as aquitards. The cone. of depression resulting
from the withdrawal of approximately 150 million gallons per
day (mgd) of water from the Miami Springs and Preston well
fields encompasses the northern half of the Airport, all of
the Miami Drum Site, and extends as far west as one-half
mile east of the 58th Street Landfill. The cone of
depression corresponding to a drawdown of 0.25 foot that
results from the withdrawal of 150 mgd of water from the new
Northwest well field and 75 mgd of water from the Miami
Springs well field encompasses the western edge of the 58th
Street Landfill. .
SITE HISTORY
'.
Varsol Spill Site
Industrial operations associated with a typical commercial
airport have resulted in hydrocarbon contamination of
surface and groundwaters in the vicinity of MIA. Since
1966, approximately 15 hydrocarbon spills and leaks have
been recorded. The total discharge of hydrocarbon materials
is estimated to be approximately 2 million gallons. This
includes the loss of an estimated 1.5 million gallons of
varsol discovered at the Eastern Airlines maintenance base
in the northeast section of the airport around 1970. During
1970 a jet fuel spill of approximately 66,000 gallons was
discovered near the west ~entral area of Eastern Airlines
properties. In 1970, National Airlines accidentally spilled
an unknown amouht of jet fuels into the drainage canals that
ultimately discharge~into the Tamiami Canal. They were
ordered to stop discharging cleaning solvents and degreasers
to an airport drainage canal at this time. In 1981, Braniff
Airlines was ordered to stop this same practice after it w~s
discovered. Several other smaller spills and discharges of
jet oil, aviation gas, cleaning solvents, and degreasers
have also occurred at the airport. Several areas within MIA
have heavy accumulations of oil lying on the ground. This
is often the result of employees from various aircraft
.'"
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maintenance operations discharging oily wastes onto the
ground and into storm sewers. Another major underground jet
fuel spill was discovered in 1983 in the vicinity of
Concourse E as a result of ongoing construction and
improvements in the area.
Removal of underground hydrocarbons at the airport was
attempted in the early 1970'5 primarily at the Eastern
Airlines maintenance base. Hydrocarbon decontamination
separator trenches were installed by Eastern Airlines in
1971 to remove the 1.5 million gallons of varsol that had
spilled underground. The recovery operations were
terminated in August 1973 due to slime build-up in the
trenches and the extremely slow natural migration of
hydrocarbons into the trenches. Actual recovered volumes
were approximately 133,000 gallons of hydrocarbons, or less
than 10 percent of the estimated spill volume. Other
recovery procedures at the airport have been implemented
only in conjunction with dewatering operations at
construction sites within the airport and have been
unsuccessful in removing substantial quantities of
hydrocarbons. During April 1981, construction activities in
the west-central area of the Eastern Airlines maintenance
base revealed a thick hydrocarbon layer floating on the
water table in an excavated trench, probably from previous
fuel spills. Eastern Airlines installed 54 shallow
observation wells during the early 1970'5 at their
maintenance base (the general area of the varsol spill).
Measurements of fluid levels in these monitoring wells,
specifically the water-table depth and hydrocarbon thickness
in the upper layer of the water table, were taken twice per
year, during the dry season and the wet season, from 1975 to
1981. The hydrocarbon layer thickness, according to these
data, shows a declining trend with time, and, in some wells,
the presence of the layer could not be detected in the
second year. In the Concourse E area, Dade County installed
43 monitoring wells t6 determine the extent and magnitude of
jet fuel spilled. Dade County also installed three recovery
wells in the Concourse E area and started the recovery
operation in mid-1983. Through May 1984, over 102,000
gallons of jet ,fuel had been recovered from this area.
Recovery operat1ons are continuing in this area.
Miami Drum Site
The privately-owned Miami Drum Services (MDS) facility
operated for approximately 15 years before Dade County,
through a local court order, forced MDS to cease operation
in June 1981. As many as 5,000 drums of various chemical
waste materials, including corrosives, solvents, phenols,
and toxic metals, were observed on the site while the
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c~mpany was' operating. Drums were washed with a caustic
cleaning solution, which, along with drum residues
containing industrial solvents, acids, and heavy metals, was
disposed of onsite in open, unlined pits. Eventually~- the
surface soils on the site became saturated.. .
The abandoned Miami Drum Site was acquired by Dade County
for construction of the Palmetto Yard maintenance fac1lity
of the Dade County Rapid Rail Transit Project. Based on a
brief study, extensive soil borings were performed at the
site during December 1981 and cores up to 10 feet deep were
analyzed for contaminants. Dade County contracted o. H. .
Materials Company and directed them to remove the 400 to 500
existing drums from the site, excavate contam1nated soils
based on these analyses, and relocate them to an existing,
approved disposal f~cility. In addition to this action, the
contaminated water encountered during excavation was
removed, treated, and disposed of onsite. At the present
time, the maintena~ce facility of the Dade County Rapid Rail
Transit system is operating at this site.
. ,
Northwest 58th Street Landfill Site
This landfill is owned by Dade County. It began operation
in 1952 as an open dump. Some waste was placed into shallow
trenches dug below th~ water table, resulting in deposition
of some refuse in the saturated zone of the aquifer. Open
burning of waste was used as a volume reduction method until
1950, when a ban was placed on such burriing. Since the ban,
waste has accumulated at a rate approximately three times
the 1960-61 rate. Since its startup in 1952, this facility
has received from 100,000 to 1,000,000 tons per year of
municipal solid waste. Garbage from domestic and industrial
sources comprises about 65 percent of the wastes disposed of
at the site. The remainder is from other sources and
includes street debris, discarded autos and appliances,
furniture, tree trimmings, liquid wastes, and other rubbish.
The estimated recent disposal rate (applicable through
July 1982) for garbage and trash was about 90,000 tons per
month: for liquid wastes, consisting mainly of grease trap
pump-outs, it w~s about 200,000 to 400,000 gallons per
month. Since January 1975, this landfill has been receiving
daily cover provided~y muck and crush~d rock from quarry
overburden and, more recently, calcium carbonate sludge from
the Miami Dade Water and Sewer Authority water treatment
plants. Since September 1982, the landfill. has been closed
for all purposes, except for the disposal, of construction
debris.
~
This site is not permitted as a sanitary landfill by the
Florida Department of Environmental Regulation (FDER).
According to preliminary close-out plans for the landfill,
.~
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it is classified as an open dump and has been operating in
violation of a consent order between the FDER and Metro Dade
County dated July 30, 1979. Final close-out plans for this
landfill are being prepared at this time.
CURRENT SITE STATUS
The initial study, conducted in 1982, involved compiling and
evaluating existing data relevant to the conta~mination
problem. This evaluation generally indicated the presence
of dispersed, low-level concentrations of numerous toxic
contaminants in the groundwater beneath the study area.
This was based on limited pertinent data, mostly inorganics.
A general lack of pertinent groundwater monitoring data,
especially organics, was found.
The Remedial Investigat~on lRI), Degun in late 1982,
consisted of a unified, planned, and intensive sampling
effort to fill in the data gaps found in the Phase I study
and to determine the magnitud~ and extent of groundwat~r
contamination. Criteria for data classification were
developed from existing literature, and were based on
effects to human health. Data evaluation based on the RI
indicated that widespread low to moderate levels of several
toxic contaminants, mostly in the volatile organics
category, are present in groundwater throughout the study
area. Vinyl chloride was the most common contaminant
detected and its concentration exceeded the FDER standard of
one ~g/L (set in 1984). No concentrated priority pollutant.
plume could be found.
Earlier investigations by Eastern Airlines, based on varsol
fluid level measurements on top of the water table, showed
declining thickness of the varsol layer with respect to
time. By 1981, most of Eastern Airlines data showed no
hydrocarbon thickness at the Varsol Spill Site. The RI in
1982 and 1983 did not ~~nd any plume or pockets of the
varsol in groundwater at and around the spill site and in
the neighboring lower Miami Springs area.
In late 1981 (pr~or to cleanup of the contaminated soils) ,
the Florida Department of Environmental Regulation (FDER)
contracted with Technos, Inc., to determ~ne the extent of
groundwater pollution associated with the Miami Drum Site.
Geophysical measurements using electromagnetics (EM) and
ground penetrating radar lGPR) provided the data for this
study. The EM results showed a significant conductivity
anomaly coincident with the site. The conductivity anomaly
provided evidence of a strong plume-like trend to the
southeast in the direction of groundwater flow and towards
the Miami Springs/Preston well fields. Several less
significant conductivity lobes were also detected towards
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the west and north or~th~ site toward the Medley well field.
However, the RI as well as a separate remedial investigation
conducted during 1983 by FDER at the Miami Drum Site found
no evidence of a conta~inant plume from the site.
During the late 1970's, investigations by the U. S.
Geological Survey and Technos, Inc., had determined that,
based on the dissolved inorganic content of the groundwater,
leachate from the 58th Street Landfill had. infiltrated the
Biscayne Aquifer beneath and adjacent to the landfill site
in the form of a groundwater plume moving in an easterly
direction along with the natural downgradient water
movement. .However, based on extensive priority pollutant
data (heavy metals as well as organics) that were
non-existent during the earlier USGS and Technos studies, no
groundwater contaminant plume was found in the vicinity of
the landfill from the 1982-1983 RI.
The results of these investigations indicate that, at this
time, there is no concentrated contaminant plume emanating
from any of the three sites in the study area. However,
widespread, low, dispersed levels of volatile organic
chemicals have been .found allover the study area; plumes
have blended together and have now, with time, become
indistinguishable with the general poor groundwater quality
in the study area. The main explanation for this is the
geohydrologic conditions within the study area: the high
transmissivity of the Biscayne Aquifer; the widespread
interaction of groundwater with surface-water bodies
throughout the study area; and the high, continuous pumping
of groundwater at the several municlpa~ well fields. The
overall groundwater quality in the study area will be
addressed in Phase IV.
~
~
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LEGEND
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". .
RECORD OF DECISION
SUMMARY OF REMEDIAL ALTERNATIYE SELECTI0N
BISCAYNE AQUIFER' SITES, DADE COUNTY, FLORIDA
PHASE I:
VARSOL SPILL SITE
-,
ALTERNATIVES EVALUATION
During the Remedial Investigation (RI), wells along NW 36th
Street were sampled for all priority pollutants. The varsol
spill was the result of underground pipeline leak(s) near
36th Street in the northeast corner of the Miami
International Airport. In addition, newly constructed wells
and existing wells, including some municipal production
wells were sampled in the area north of' the airport because
the migration of the varsol toward the Lower Miami Springs
wellfield was of concern. The location of the wells sampled
and the geographical areas defined for data evaluation are
shown in Figure 4. Oil and grease samples were also
collected at most of the above wells as an indicator of any
varsol remaining on the water table or in the soil at these
locations.
A summary of the results for the airport area and the Lower
Miami Springs area are shown in Tables 1 and 2,
respectively. The analytical results for the airport area "
are comparable to those in the other geographical areas.
Table 3 lists the mean values of vinyl chloride,
trans-1,2-dichloroethene (the two VOCs most commonly
detected), as well as the total concentrations of all
priority pollutant VOCs detected. Th~s table indicates that
the airport area water is of similar quality as that all
over the remaining study area. . This, can also be seen from
Figure 5, which shows'po~itive VOC results allover the
study area. Table 4 lists in decreasing order the mean
concentration of vinyl chloride detected in each well in the
study area. Wells with mean concentrations of vinyl
chloride below 1.0 ~g/L are not listed. Table 5 pres~nts
similar information for total volatile organics (priority
pollutants). T~bles 4 and 5 also confirm the conclusion
that water quality at this site is similar to that allover
. the study area.
No oil and grease were detected in the wells along 36th.
Street. In the Lower Miami Springs area, oil and grease
were found at the minimum detection limit of 5 mg/L in two
wells, A-3 and A-4, but only once out of the five times they
were sampled. These results do not show any evidence of any
varsol remaining in the soil or water at this time.
gnR290/03
-1-
I .
[
-------
The wells along 36th Street and immediately north of it in
the Lower Miami Springs area were sampled again in October
1983 (in addition to the six samples collected in November
1982 and March 1983). The results of this additional
sampling agree with the earlier findings summarized above.
These results show that the varsol spilled during the late
1960's at the airport is not present at this time at this
location. Also, there is no evidence of its migration
toward the Miami Springs municipal well field. The
hydrocarbon layer thickness was non-existent during the late
1970's, according to Eastern Airlines studies, and the 1982
and 1983 RI also confirms this conclusion. These findings
give further impetus to the following statement in the
report of our initial evaluation (October 1982): "A study
of this problem has indicated that some microbial
decomposition of the underground hydrocarbons is being
accomplished by bacteria present in the soils." These
results call for no action at this site.
.'"
RECOMMENDED ALTERNATIVE
In view of the fact that no trace of the varsol was found at
this time in and around the airport, the recommended
alternative for this site is no action.
Although large concentrations of spilled jet-A fuel were
found in the groundwater near Concourse E of the airport,
CERCLA (Superfund) does not address jet fuel spills.
However, recovery o~ the fuel should continue and the
contaminated groundwater there should be treated in
accordance with Dade County regulations.
FUTURE ACTIONS
While no varsol was found in and around the airport, the
spill did occur. Several factors could contribute to the
fact that no varsol is detectable at this time. Some of the
solvent was recovered and biodegradation is believed to have
destroyed some more; however, the hydrology of the aquifer
system strongly~suggests that some of the solvent
contributed to and became a part of the "background"
contamination in the aquifer, as shown in attached Tables
and Figures. This "background" contamination will be
addressed in a separate Record of Decision (Phase IV) as
part of the remedy for the three sites referred to as the
Biscayne Aquifer Superfund Sites.
-2-
ATT46/d.1
-------
~- .~----~--~ - .
. . . ~, .
. . -. ._-
-.-----..-,.. .'
: WELL DESIGNATION
PARAMETER MWI MW2 MW3 MW4 ~5 MW6 MW7 MW8 MW9 MWII
.
S D 5 D 5 D S D S D S. D S D 5 D D D
ARSENIC 0 b
CADMIUM 0 0 0
CHROMIUM 0 0 0 0 0 0 0 0 0
en LEAD 0 0 0 0 0 0 0 0
(.)
Z MERCURY 0 0 0
c(
<' SELENIUM 0 0
a:
0 ZINC 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
l:
en
~
Z
c(
~
:) CHLOROBENZENE 0 0 0 0
-'
-'
0 CHLOROETHANE I:::. I:::. t::.
IL.
= 1,1 -DtCHLOROETHANE . 0 0 0
iiE en 0 0 0 0
(.) TRANS-1.2-DICHLOROETHENE
0 i
iiE 1,1.2.2- TETRACHLOROETHANE . .
IL. a::
<' TOLUENE 0 0 0
0
w 1.1.1- TRICHLOROETHANE 0 0 0 0
-'
~ TRICHLOROETHENE 0 0 0
~
0 VINYL CHLORIDE 0 0 0 0 0 . 0 .
.> "
TOTAL RECOVERABLE PHENOtS t::. t::. t::. I:::. t::. I:::. I:::. I:::.
ACETONE t::.
DIMETHYL SULFIDE t::.
(.) METHYL BUTYL KETONE t::. t::. t::.
zen METHYL ETHYL KETONE I:::.
-------
.' wELL DESIGNATION
PARAMETER '" . "' .., 'r ell D u '0 ... D U '0 '" D u '0
. - en o. en en
'r 'r VI VI 'r 'r 'r ..., '( '( '( - - - -
en ... ... ~ ~ ~ ~ ~ « « « « « « « « « « .( «
ARSENIC 0
CADMIUM 0 0 0
CHROMIUM 0 0 0 0 0
VI
° COPPER 0 0
Z 0 0 0
< LEAD
C!J
a: MERCURY 0 0 0
0
~ SELENIUM 0 0 0 0 0
ZINC 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
en
~
Z BENZENE O .
<
~ 0 0 0 0
:I CHLOROBENZENE 0 0 0 0
-'
-' CHLOROETHANE 6 6
0
A.
~ CHLOROMETHANE 6
... en 0
~ ° 1,1-DICHLOROETHANE 0
0 Z TRANS-1.2-DICHLOROETHENE 0 0 0
~ < 0 0
A. a: 0
C!J ETHYL BENZENE 0
0
w METHYLENE CHLORIDE . . .
:4 1,1.2.2- TETRACHLOROETHANE
~ .
<
-' TETRACHLOROETHENE 0 0
0
> TOLUENE 0 0 0 0
0
VINYL CHLORIDE - -.. . 0 O . . 0 0 0 0 a -
TOTAL RECOVERABLE PHENOLS 6
OIL & GREASe 0 0
ACETONE 6 6
C8 ALKYLPHENOL 6
DIMETHYLHEPT ANE 6
METHYL BUTYL KETONE 6
° METHYL SULFIDE 6
Z(/)
<0 STYRENE 0
C!JZ
a::I
00 M-XYLENE 0
a.
a::::iE O&P-XYLENE 0 0 0 0
~o
....0. UNIDENTIFIED COMPOUNDS (EXTRACTABLE) 6 6 6
0
LEGEND
6 Detected in at least one sample.
no criteria given.'
0 Detected in at least one sample. but
al level' less Ihan established criteria.' TABLE 2.~
. Detected in at least o"e sample Contaminants Detected in the ~ .
at levels above criteria.' Lower Miami Springs Area. - .
'Criteria in RI Report (Feb. 1984. Table 4-21
-------
...... ... --... u' ........~--.
~h'." --.. ..
-. .'---"" ....._~-_... .. ...._-',--....1.....~.. .i.-...:....-'..u__.~ ..--.-.....- '_;"""'_.-_"":_'~"_.'''._-'-_..'''-''--''--'.f''.-.--'.'''''- ....-..--..--...--- . -.---.-----.-.-.
."
Table 3
ME»I VALUES OF SELECT ANALYTICAL PARAMETERS
FOR \?RIOUS GEOGRAPHICAL AREAS
Total Vinyl
Geographical Area VOCs Chloride Trans-l,2-dichloroethene
Airport Monitoring Wells 10 3.5 1.1
Lower Miami Springs Wells 20 8.7 3.6'
Upper Miami Springs Wells 33 17 7.3
Hialeah Area Wells 57 23 28
58th Street Landfill Wells 6.2 0.31 0.53 '. -
Unsewered Industrial Area Wells 1.0 0.25 0.25
Notes:
1.
All values reported in'~g/L.
2.
There are fewer .~onitoring wells in the Unsewered Industrial
Area than in other areas. Results of analyses from these wells
might not be indicative of the water quality of the whole area.
"
gnR290/04/l
-5-
-------
Well No.
C-lB(5l)
C-1C (101)
G-1280 (54)
F-414(65)
F-255(82)
MS-9(105)
MS-8 (64)
P-5 (85)
MW-6D(55)
MW-llD (55)
P-3 (85)
LM-10(30)
MS-3(62)
P-2 (85)
MS':19 (106)
MS-20(106)
TP-MSR
MS-2(96)
TP-PR
F-239 (53)
LM-10(60)
MS-1'2 (B5)
MW-5D (56)
TP-MSF
M-3 (132)
TP-PF
MS-23 (97)
P-7 (B5)
P-4(B5)
MW-4D (71)
gnR290/04/2
,""
Table 4
MEAN CONCENTRATION OF VINYL CHLORIDE
DETECTED AT INDIVIDUAL SAMPLING STATIONS
Location
Mean Concentration
( ~g/L)
Upper Miami Springs Area
Upper Miami Springs Area
Hialeah Area
Lower Miami Springs Area
Hialeah Area
Upper Miami Springs Area
Lower Miami Springs Area
Hialeah Area
Airport Monitoring Wells
Airport Monitoring Wells
Hialeah Area
Upper Miami Springs Area
Lower Miami Springs Area
Hialeah Area
Upper Miami Springs Area
Upper Miami Springs Area
Hialeah Water Treatment Plant--Raw
Lower Miami Springs Area
Preston Water Treatment Plant--Raw
Hialeah Area
Upper Miami Springs Area
Hialeah Area
"
Airport Monitoring Wells
Hialeah Water Treatment Plant--Finished
Upper Miami Springs Area
Preston Water Treatment Plant--Finished
Upper Miami Springs Area
Hialeah Area
Hialeah Area
Airport Monitoring Wells
-6-
.-
142
111
100
68
59
51
37
32
24
23
19
17
16
12
10
10
9.8
9.5
9.3
8.9
8.0
6.5
6.2
6.1
5.5
5.3
5.2
5.1
4.6
3.5
-------
Well No.
MS-l (67)
A-1C(86)
MW-7D(53)
P-l(85)
A-3C (88)
MW-3S (12)
A-4B(50)
A-.3B (51)
Ut-9(30)
M-l(132)
HW-5S(11)
M-2 (131)
.'"
Table 4.
(continued)
Location
Mean Concentration
( ~g/L)
3.5
Lower Miami Springs Area
Lower Miami Springs Area
3.3
2.9
Airport Monitoring Wells
Hialeah Area
2.1
1.8
Lower Miami Springs Area
Airport Monitoring Wells
1.6
1.6
Lower Miami Springs Area
Lower Mi~i Springs Area
1.6
1.3
58th Street Landfill Area
Upper Miami Springs Area
Airport Monitoring Wells
1.3
1.2
1.0
Upper Miami Springs Area
Note:
All other stations have mean concentrations less than 1.0 ~g/L.
".
gnR290/04/3
"
..
."'"
-7-
-------
Table 5
MEAN CONCENTRATION OF TOTAL VOLATILE ORGANICS
(PRIORITY POLLUTANTS) DETECTED AT INDIVIDUAL SAMPLING STATIONS
Well No.
C-1B(Sl)
C-1C(101)
G-1280 (54)
F-414 (65)
MS-20 (106)
F-255(82)
F-239(53)
MS-9(105)
P-5 (85)
MS-8 (64)
MW-3S(12)
TP-MSF
MW-6S(1l)
LM-10(30)
P-'2(85)
P-7(85)
P-3(85)
TP-PR
TP-MSR
MS-19(106)
MS-3(62)
TP":PF
LM-10(60)
MW-IS(11)
M-2 (131)
MW-9D (42)
MS-22 (92)
MS - 2 ( 9 6 )
A-3B(51)
MS-12 (85)
gnR290/04/4
Location
Mean Concentration
(1Jg/L)
166
151
146
137
119
108
102
101
80
76
56
54
46
43
38
37
36
35
27
26
26
26
25
25
25
20
20
19
18
16
Upper Miami Springs Area
Upper Miami Springs Area
Hialeah Area
Lower Miami Springs Area
Upper Miami Springs Area
Hialeah Area
Hialeah Area
Upper Miami ?.prings Area
Hialeah Area
Lower Miami Springs Area
Airport Monitoring Wells
Hialeah Water Treatment Plant--Finished
Airport Monitoring Wells
Upper Miami Springs Area
Hialeah Area
Hialeah Area
Hialeah Area
Preston Water Treatment Plant-'-Raw
Hialeah Water Treatment Plant--Raw
Upper Miami Springs Area
Lower Miami Springs Area
Preston Water Treatment P1ant--Finished
.
Upper Miami Springs Area
Airport Monitoring Wells
Upper Miami Springs Area
Airport Monitoring Wells
Upper Miami Springs Area
Lower Miami Springs Area
Lower Miami Springs Area
Hialeah Area
-8-
-------
-----.---;-; ------------------------- -
----------.;-------
. -.. .---.--.--
Table 5
(continued)
Mean Concentration
Well No. Location ( \Jg/L)
A-4C(90) Lower Miami Springs Area 16
P-l (85) Hialeah Area 15
LM-4A (20) 58th Street Landfill Area 14
MS-23 (97) Upper Miami Springs Area 13
MW-2D(47) Airport Monitoring Wells 13
LM-5A(10) 58th Street Landfill Area 13
B~5A (18) Unsewered Industrial Area 12
P-4 (85) Hialeah Area 12
,""
MW-2S(11) Airport Monitoring Wells 12
MW-15D (55) Other Sampling Stations 12
M-l (132) Upper Miami Springs Area 11.
LM-4A ( 40) 58th Street Landfill Area 11
LM-9 (10) 58th Street Landfill Area 10
A-4A(18) Lower Miami Springs Area 10
LM-4A (64) 58th Street Landfill 10
LM-9(30) 58th Street Landfill 9.0
LM-5A (30) 58th St;eet Landfill 8.8
M-6(131) Upper Miami Springs Area 8.2
F-44l (57) Lower Miami Springs Area 8.1
LM-8(30) 58th Street Landfill Area 7.6
A-l (C) (86) Lower Miami Springs Area 7.3
LM-8(60) 58th Street Landfill Area 7.2
.
G-1368(38) Hialef!h Area 7.0
.MW-4S (12) Airport Mon~toring Wells 6.1
LM-6A (60) 58th Street Landfill Area 5.7
LM-5A(60) 58th Street Landfill Area 5.7
l'i-3 (132) Upper Miami Springs Area 4.8
LM-8(10) 58th Street Landfill Area 4.3
LM-6A(10) 58th Street Landfill Area ". 3.7
MS-l(67) Lower Miami Springs Area 3.5
M-4(129) Upper Miami Springs Area 3.3
gnR290/04/S
-9-
-------
Well No.
LM-7A(60)
LM-6A(30)
A-4A(18)
MW-8S(1l)
MS-17 (106)
MW-llD (55)
A,...4B(50)
LM-l(lO)
B-4B(51)
LM-IO(lO)
MW-1D(53)
MW-4D(71)
MS-16 (106)
, .~
Table 5
(continued)
Location
Mean Concentration
( ~g/L)
Upper Miami Springs Area
58th Street Landfill
3.0
3.0
Lower Miami Springs Area
Airport Monitoring Wells
2.7
2.5
Upper Miami Springs Area
Airport Monitoring Wells
2.2
2.2
Lower Miami Springs Area
Other Sampling Stations
2.0
1.9
Unsewered Industrial Area
1.5
1.5
Upper Miami Springs Area
Airport Monitoring Wells
1.0
1.0
Airport Monitoring Wells
Upper Miami Springs Area
1.0
Note:
All other stations have mean concentrations less than 1.0~g/L.
gnR290/04/6
..
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,
COMMUNITY RELATIONS
RESPONSIVENESS SU~~RY
BISCAYNE AQUIFER SITES
FEASIBILITY STUDY
.-'"
INTRODUCTION
EPA held a public ~eeting on February 7, 1985 at the Miami
Springs City Hall to discuss the Feasibility Study (FS)
report for the Biscayne Aquifer site and to accept public
comment. The meeting, held from 7:30 to 11:00 p.m., was
attended by 34 people.
James Orban, EPA's site manager for the-project, chaired the
meeting. He was assisted by Udai Singh and Ken Cable from
CH2M HILL, EPA's technical consultant. They provided a
brief description of the site history, the nature of the
problem and the findings of the Remedial Investigation (RI). .
This was followed by a more detailed presentation of the
cleanup alternatives considered and the recommended actions.
Mr. Orban then requested questions and comments from the
audience and stated that EPA would also accept written
comments until February 28, 1985. He indicated that all
comments would be considered in the decision making process
and that a written response to the comments would be
included in the Record of Decision.
. -
SU~~RY OF PUBLIC COMMENT AND AGENCY RESPONSE
Questions and comments offered at the meeting are summarized
below. They are divided into three categories: general
comments relating to the project as. a whole, those
pertaining to specific sites, and thos~ concerning
recommended cleanup activities for the -~area' s groundwater.
No written comments were received during the public comment
period.
GENERAL COMMENTS/QUESTIONS
1.
Public In~olvement: Speakers thought that public
notice for the,meeting was inadequate, that there had
not been sufficient involvement of citizens during the
study process, and that the plans had been prepared
"behind closed doors".
Response: Public notice for the meeting was provided
by display advertisements in the Ft. Lauderdale News
and the Miami Herald. A press ~elease announcing the
meeting was distributed to all lbcal newspapers. The
RI and FS reports were available for public review at
the Palm Beach, Dade and Broward County offices. EPA
gnCH13/d.1602
1
I ,
i I
-------
-~
t
had previously implemented an extensive community
relations program for the site.
A public meeting was held in September 1982 to present
the results of the initial study and to outline the
plans for Remedial Investigations. Three issues of
Remedies, a newsletter summarizing project activities
and reports, were mailed to over 400 individuals and
organizations in October 1983, March 1984 and
July 1984.
A public meeting to present the Remedial Investigation
findings, outline the Feasibility Study activities, and
solicit comments on possible cleanup alternatives to be
evaluated was held in October 1983. Preliminary
results of the detailed evaluation of the remedial
action alternatives were explained in a public meeting
in March 1984. Also presented for comments and
suggestions at this meeting was the preliminary outline
of the program for the protection of the Biscayne
Aquifer.
EPA sponsored another public meeting in July 1984 to
present and receive public comment on the recommended
alternatives and the Biscayne Aquifer Protection Plan.
Two workshops on study findings, risk assessments, and
proposed cleanup and prevention activities were held
for the press, elected and appointed officials and the
general public during July 1984. :EPA believes these
activities provided excellent opportunities in both
formal and informal settings for two-way communication
between interested citizens and the agencies: EPA,
Florida Department of Environmental Regulation, D~de
County Department of Environmental Resources
Management, and the Centers for Disease Control.
2.
Funding for Cleanup: Questions concerned the
availability of EPA funds for implementation of cleanup
activities, private sector responsibility for cleanup,
and incentives to encourage private sector site
cleanup. ~ommentors indicated that water user charges
should not'be used to fund cleanup actions.
Response: EPA has identified the responsible parties,
and will influence these parties to do what is
necessary to cleanup the site. EPA will also use
available S~perfund monies to implement the cleanup.
3 .
Local Agencies: Speakers expressed a lack of
confidence in the ability of county agencies to deal
with hazardous waste issues. They were critical of the
County's hydrocarbon removal operation at the airport,
the lack of technical training or Dade County
gnCM13/d.1602
r
2
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. .
..
.
.1.
Department of Community Affairs staff, inaccuracies in
the County's report on Munisport landfill, operation of
the 58th Street landfill, and the lack of information
about contamination on the wes~ side of the airport.
- Response: EPA pursued the Remedial Investigation and
Feasibility Study for the Biscay~e Aquifer and made
recommendations for cleanup activities under the
'authority of the Superfund program. Expenditure of
program funds is limited to cleanup of existing
uncontrolled hazardous waste sites and cannot be
extended to cover costs of developing and implementing
plans designed to prevent the occurrence of future
hazardous waste disposal problems. These are
responsibilities of local agencie~~
4.
Federal Agencies: Commentors indicated that the
process for study and cleanup of sites takes too long,
and that EPA should have proposed an Environmental
Impact Statement (EIS) on the use of wetlands near the
Northwest well field for industrial development.
Response: EPA recognizes that the length of the
Remedial Investigation and Feasibility Study process
causes frustration among local residents who are
concerned about the effects of the sites on their
health and property values. Yet, if the problems arc
to be effectively solved it is essential that they be
thoroughly understood before long term cleanup actions
are recommended. At Biscayne Aquifer, this required
extensive testing at a number of different sites and
evaluation of 12 source control and 10 offsite remedial
action alternatives. These activities were
accomplished as expediently as. possible.
-
Responsibility for implementation of
within a different division of EPA.
refer the request to the appropriate
for further consideration.
an EIS rests
Officials will
section within EPA
<
SITE SPECIFIC CO~mNTS/QUESTIONS
.
Varsol Spill Site-: . CommentoJ:s thought the presence of
hydrocarbons at the airport site should have been a
target for Superfund action.
Response: As the speaker indicated, hydrocarbons are
not included in the list of hazardous substances
regulated by the Superfund program. The project
studies did assist the State and local. officials in
identifying and addressing the problem. However,
formal Superfund action is not appropriate.
gnCM13/d.1602
3
-------
. .
.
Over 1.5 million gallons of Varsol were believed to
have been spilled at the site in 1968. EPA conducted
an extensive sampling program at the site, but was
unable to confirm the presence of a plume of toxic
substances. It is possible that the solvent was
biodegraded or dispersed through the aquifer.
2.
Miami Drum Site and 58th Street Landfill:
a.
Speakers suggested that EPA in its RI did not
identify a contaminant plume at the 58th Street
landfill because it did not have much concern
about contaminant migration since the adjacent
Miami Springs well field is only used as a back-up
water supply source.
Response: The presence of a contaminant plume in
groundwater downgrade of the 58th Street landfill
was documented in the late 1970s by the U.S.
Geological Survey and various studies by
consultants; however, that was a non-toxic,
non-organic substance survey. Between November
1982 and March 1983 EPA conducted a more
comprehensive survey; a series of six sampling
programs which tested for all 129 priority
pollutants, including organic as well as inorganic
toxic substances.
b.
Speakers thought EPA's focus on municipal drinking
water and groundwater was too narrow and did not'
permit sufficient consideration of problems that
require attention at these sites. They were
concerned about cleanup and closure of the 58th
Street landfill and felt these activities should
be included as recommended remedial actions.
Response: EPA considered a wide range of
alternatives'~or remedial action at the sites,
related both to specific sources of contamination
as well as to the offsite, area-wide nature of the
proble~. EPA did include in the FS an analysis of
remedial alternatives for the 58th Street
landfill, including proper closure.
RECOMMENDED ACTION COMMENTS/QUESTIONS
1.
Recommendation Development: One speaker questioned the
process of developing recommendations for cleanup
actions and indicated he did not feel the
recommendations covered all problems identified by
project studies. He suggested consideration of a
variation of Alternative 3 that would keep Preston and
Miami Springs well fields open for emergency back-up
gnCHl3/d.l602
4
-------
------ -- _.
..
2.
I :
-- . ..
, } ~ .:., --<-.'. \: :(-------- ~~.. ~-,~~. _.':'-,,;' ._;~ -.
..
, .
and would implement plans to minimize future.
contamination in the Miami Springs area.
Response: EPA performed a detailed evaluation of
Alternative 3 and found that it was no~ cost-effective
(the total present worth cost for Alternative 3 was'
over $23 million as compared to the cost of the
recommended alternative; $8.5 million). Alternative 3
also would not satisfy one of the important goals of
the study; to cleanup the aquifer, which will be
accomplished by pumping from the Miami Springs and
Preston well fields. .
Biscayne Aquifer Protection Plan: Speakers identified
the need for federal protection of.wetlands in the
Northwest well field area. They suggested preparation
of an EIS or use of EPA's veto power over Corps of
Engineers' 404C permits to control land development
near the new Northwest well field.
Response: The suggested actions ~re not within the
domain of the Superfund branch at EPA. Officials will
refer this recommendation for consideration to the
proper division within EPA.
.
'.
3.
Air Stripping: Commentors were concerned about the
health effects of airborne pollution on people living
near the proposed tower sites. They asked about the
benefits of air stripping and the end result of the
remedial action on water quality.
Response: EPA completed a detailed estimate of air
pollution resulting from air stripping towers and found
that air stripping ~eets all state air emission
requirements and is far below allowable air emission
limits. It will not have adverse impacts upon the
environment or human health. The benefit of air
stripping is that it will be removing 97. percent to
over 99 percent of the volatile organic compounds from
the water withdrawn from the Miami Springs and Preston
municipal well fields, thus considerably improving the
quality of potable water in the study area.
4.
"
Effect on Land Values: One speaker was conceined about
the effect of the cleanup activities on land values in
her Miami Springs neighborhooq. She wanted to know the
effect of the recommended alternative on her property
value.
Response: The Miami Springs and Preston well fields
had been pumping for 20 to 30 years, artificially
lowering the water table in the area. When pumping
began at the new Northwest well field and the Hiami
gnCl-1l3/ d . 1602
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Springs and Preston well fields were shut downr the
water table in the area rose, causing flooding of
residential properties. .
EPA's recommendation is to begin pump~ng the Miami
Springs and Preston well fields, and to treat the water
by air stripping so as to provide clean water to the
public. Although this study was not meant to address
the flooding problem at the sites, the effect of the
recommended action is to return the water table to its
former position, thus resolving the flooding problem.
WDR9l/00l
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gnCM13/d.1602
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