PB97-963133
EPA/541/R-97/120
January 1998
EPA Superfund
Record of Decision Amendment:
Bailey Waste Disposal
Bridge City, TX
12/16/1996
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RECORD OF DECISION
AMENDMENT
BAILEY WASTE DISPOSAL
SUPERFUND SITE
REGION 6
DECEMBER 1996
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DECLARATION
BAILEY WASTE DISPOSAL SUPERFUND SITE
AMENDED RECORD OF DECISION
DECEMBER 1996
SITE NAME AND LOCATION
Bailey Waste Disposal Superfund Site
Orange County, Texas
STATEMENT OF BASIS AND PURPOSE
This decision document presents the amended Record of Decision (ROD
Amendment) for the Bailey Waste Disposal site (the site) in Orange County, Texas.
The amended remedy was chosen in accordance with the Comprehensive
Environmental Response, Compensation and Liability Act of 1980 (CERCLA), as
amended by the Superfund Amendments and Reauthorization Act of 1986 (SARA) and,
to the extent practicable, the National Oil and Hazardous Substances Pollution
Contingency Plan (NCP). This ROD Amendment is based on the administrative record
file for this site.
The State of Texas concurs with the ROD Amendment.
DESCRIPTION OF THE AMENDED REMEDY
This ROD Amendment addresses the environmental threat at the site by
consolidating and capping the waste to prevent human contact and future migration.
Major components of the amended remedy include:
• waste consolidation within the site's waste areas (i.e., East Dike Area, North
Dike Area);
• grading of the waste areas using general fills to provide a mild slope for the base
of the cap and to promote storm water runoff;
• construction of a lightweight composite cap and related appurtenances with
modification as appropriate to satisfy site-specific design criteria and constraints;
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installation of a consolidation water collection system to intercept and remove
groundwater that rises in the short term (i.e., during construction of the cap) due
to consolidation of the waste (this water will be treated using the onsite
treatment facility);
installation of storm water management controls to treat storm water runoff from
disturbed areas during construction and to divert storm water runoff away from
inactive or completed areas of the site;
modifications to existing dikes and side slopes to include adjustment of top
elevations to tie into the cap, repair/modifications of areas that have experienced
excessive settlement, and erosion/slops protection measures; and
construction and maintenance of access roads.
STATUTORY DETERMINATIONS
The amended remedy is protective of human health and the environment,
complies with Federal and State of Texas requirements that are legally applicable or
relevant and appropriate to the remedial action, and will be cost effective. This remedy
will utilize permanent solutions to the maximum extent practicable.
Because the amended remedy will result in hazardous substances remaining
onsite, a review will be conducted five years after the commencement of remedial
action to ensure that the remedy continues to provide adequate protection of public
health and welfare and the environment.
fib
N.lpiginaw '* Date
fegiona Administrator
Region 6
ii
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TABLE OF CONTENTS
PAGE
DECLARATION
1.0 INTRODUCTION 1
1.1 Site Background 1
1.2 Lead and Support Agencies 3
1.3 Statute that required ROD Amendment 3
1.4 Circumstances that led to the need for a ROD Amendment 3
1.5 Administrative Record 8
2.0 REASONS FOR ISSUING A ROD AMENDMENT 8
2.1 -Remedy Selected in ROD 8
2.2 Rationale for Changing Remedy Selected in the ROD 9
2.3 Amended Remedy 10
3.0 COMPARATIVE ANALYSIS 11
3.1 Treatment Components 11
3.2 Containment Components 13
3.3 Groundwater Components 15
3.4 General Components 15
3.5 Major Applicable or Relevant and Appropriate Requirements 16
(ARARs)
4.0 EVALUATION OF ALTERNATIVES 17
4.1 Threshold Criteria 18
4.2 Primary Balancing Criteria 18
4.3 Modifying Criteria 19
4.4 Nine Criteria Evaluation 20
4.4.1 Overall Protection of Human Health 20
and the Environment
4.4.2 Compliance with Applicable Relevant and 21
Appropriate Requirements (ARARs)
4.4.3 Long-term Effectiveness and Permanence 22
4.4.4 Reduction of Toxicity, Mobility, or Volume 22
Through Treatment
4.4.5 Short-term Effectiveness 23
4.4.6 Implementability 23
4.4.7 Cost 24
4.4.8 State Acceptance 24
4.4.9 Community Acceptance 24
iii
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TABLE OF CONTENTS
(continued)
PAGE
5.0 STATUTORY DETERMINATIONS 25
5.1 Protection of Human Health and the Environment 25
5.2 Attainment of Applicable or Relevant and Appropriate 25
Requirements of Environmental Laws
5.3 Cost Effectiveness 25
5.4 Utilization of Permanent Solutions and Alternative Treatment 26
Technologies or Resource Recovery Technologies to the
Maximum Extent Practical
5.5 Preference for Treatment as a Principal Element 26
6.0 DOCUMENTATION OF SIGNIFICANT CHANGES 27
FIGURES
Figure 1: Vicinity Map 2
Figure 2: Site Map 6
TABLES
Tablet Surface Water Discharge Criteria 12
IV
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1.0. INTRODUCTION
In this amended Record of Decision (ROD Amendment), the United States
Environmental Protection Agency (USEPA) describes its rationale for implementing an
amended remedy at the Bailey Waste Disposal Superfund site. The amended remedy
addresses the environmental threat at the site by consolidating and capping the waste
to prevent human contact and future migration. This ROD Amendment will document
the rationale for the amendment, evaluate the original remedy and the amended
remedy using the nine evaluation criteria, and will discuss how the amended remedy
satisfies the statutory requirements. Because this ROD Amendment allows for a
fundamentally different approach from the one outlined in the original June 1988 ROD
(original ROD), was necessary for the USEPA to propose the alternate remedial
approach and solicit public input before issuing this ROD Amendment.
1.1 Site Background:
The Bailey Waste Disposal Superfund site is located approximately three miles
southwest of Bridge City in Orange County, Texas (See Figure 1). The site was
originally part of a tidal marsh near the confluence of the Neches River and Sabine
Lake. In the early 1950s, Mr. Joe Bailey constructed two ponds: Pond A and Pond B.
The ponds were reportedly constructed by dredging the marsh and piling the marsh
sediments to form dikes along the northern and eastern limits of Pond A (the North Dike
and East Dike Area, respectively). Between the time of construction (1950s) and the
spring of 1971, Mr. Bailey used a variety of wastes including industrial waste (primarily
organics including tar-like wastes), municipal solid waste, and debris as fill material for
these dikes.
In 1984, the USEPA proposed the site for inclusion on the National Priorities List
(NPL). The site was placed on the NPL in 1986. A remedial investigation (Rl) was
completed for the site in October 1987 (Woodward-Clyde Consultants, 1987), and a
feasibility study (FS) was completed in April 1988 [Engineering Science, Inc.
(Engineering-Science), 1988]. The Rl concluded the following: the site has had no
impact on drinking water; and in the unlikely event that site constituents were to migrate
via a groundwater pathway, it would take more than 800 years for them to reach
potable groundwater. The shallow groundwater beneath and adjacent to the site is
saline and not suitable for human consumption. The closest public drinking water
supply well, located approximately 1.5 miles northeast of the site, is estimated to be
approximately 385 feet deep. The nearest municipal water supply wells are located
approximately 2.6 miles northeast of the site and have a reported depth of
approximately 585 feet. There has been no development in the immediate vicinity of
the Bailey site, nor is it likely to be suitable for future development due to prohibitions
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FIGURE 1
BAILEY WASTE DISPOSAL SITE
ORANGE COUNTY, TEXAS
Orange
County
Bailey Waste
Disposal
Bridge City
Bailey Waste
Disposal
The Bailey
Waste Disposal
site is located
three miles
southwest of
Bridge City in
Orange County,
Texas
East Dfce
Area
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against development in wetland areas. However, existing site conditions could
degrade through a flood or other natural occurrences, releasing the contaminants
contained in the dikes into the surrounding marsh.
In the FS report, Engineering-Science recommended in-situ solidification of the
onsite waste and construction of a clay cap over the waste as the preferred remedy for
the site. USEPA selected this remedy in the original ROD for the site. The Bailey Site
Settlors Committee (BSSC), a group of potentially responsible parties, agreed to
perform the remedy in the original ROD pursuant to a judicial consent decree.
1.2 Lead and Support Agencies:
U.S. Environmental Protection Agency - Lead Agency
Texas Natural Resource Conservation Commission (TNRCC) - Support Agency
1.3 Statute that required ROD Amendment:
Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA),
§117 and National Oil and Hazardous Substances Contingency Plan (NCP)
§300.435(c)(2)(ii).
1.4 Circumstances that led to the need for a ROD Amendment
An amendment to the June 1988 ROD is necessary as a result of difficulties
associated with the implementation of the original remedy (waste consolidation, waste
stabilization and capping). Since the original ROD was signed, a number of activities
have occurred at the site which are summarized below. These activities include
remedial actions associated with the implementation of the original remedy, site
investigation activities associated with the development of the Focused Feasibility
Study (FFS), and remedial actions implemented during the FFS.
Activities Associated with the Implementation of the Original Remedy
The remedial design (RD) for the original remedy specified that the onsite
wastes must be solidified to a minimum unconfined compressive strength of 25 pounds
per square inch (psi) and a hydraulic conductivity of not more than 1x10* centimeters
per second (cm/s). Implied in these performance requirements is a reduction of
toxicity, or teachability, of the waste.
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During the RD, a stabilization evaluation study was conducted. Results of the
study are documented in the Stabilization Evaluation Report (Harding Lawson
Associates, February 1991). Major findings presented in the report include:
• "The measured permeabilities of the stabilized waste met the requirement of 1&6
cm/sec and in many cases were less than 1&7 cm/sec. Generally, the
premeabilities of the stabilized waste were one order of magnitude lower than
untreated waste.
• The results of chemical analyses performed on the stabilized waste indicated an
average extractable metals reduction of 59 percent in the majority of samples,
. and a slight decrease in semi-volatiles and volatiles.
• The stabilization techniques that appear to be the most appropriate are inject and
mix, and excavation/stabilization, depending upon the type of waste, and the type
and amount of debris present in the waste. For the two most difficult areas,
where the waste has the consistency of tar, all techniques scored low. Special
handling may be required for these areas."
The RD was completed in February 1992. After solicitation of bids and selection
of a remedial action (RA) contractor, the selected contractor mobilized to the site in
September 1992. After mobilization, the contractor's next task was to better define the
extent and volume of site wastes by boring and trenching the waste areas. As a result
of this activity, the estimated volume of site waste increased from approximately
100,000 cubic yards to 156,000 cubic yards. The majority of additional waste was
found in the North Dike Area and resulted in a modification of the design for this area.
Basically, the area! extent and required depth for stabilization activities were increased
to address the additional waste in the North Dike Area. Other initial site activities
included the construction of an onsite water treatment plant, reinforcing the site access
bridge, and construction of an earthen dike around the East Dike Area. These
activities were completed during the summer of 1993.
Upon completion of the earthen dike around the East Dike Area, the contractor
excavated 2,123 cubic yards of waste from the site's Drum Disposal Area and placed
this waste into the south end of the East Dike Area. A few corroded drums were found
in the Drum Disposal Area, but the majority of the wastes in this area (a saturated
soil/black rubber crumb material) were not contained in drums. In-situ waste
stabilization activities then began. Over the next several months, the contractor tried
several in-situ stabilization techniques including:
• the Millgard (MEC-TOOL) system - a vertical rotary auger, inject and mix system;
• the Piranha system - a rotary drum, inject and mix system; and
• mixing of the waste and stabilization agents (i.e., cement) with a backhoe.
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The contractor's stabilization techniques were unable to consistently meet the
project stabilization specifications. While a majority of the stabilized waste samples
exceeded the minimum unconfined compressive strength requirement (25 pounds per
square inch), a majority of the tested samples failed the permeability specification
(samples had a hydraulic conductivity of greater than 1 x 1CT6 centimeters per second),
based upon laboratory testing of cored samples. By January 1994 the contractor
stopped its in-situ stabilization efforts claiming the project's in-situ stabilization
specifications were not achievable. Figure 2 shows the approximate area of the East
Dike in which contractor attempted to stabilize waste.
In an effort to determine if the in-situ stabilization specifications were achievable,
the BSSC hired contractors to conduct a pilot scale in-situ stabilization demonstration
within the site's East Dike Area. The in-situ stabilization demonstration started in the
later part of 1994 and was completed in February 1995. The contractors were able to
achieve the project stabilization specifications in the pilot study area; however,
achievement of the stabilization specifications relied upon sampling the stabilized
material in the uncured (wet sampling) state. The "wet sampling" method differed from
the previous specified sampling method in that samples were taken from the pilot test
area shortly after mixing waste with stabilizing agents and allowing the sample to cure
(i.e., harden) in the laboratory before testing. The previously specified sampling
method required letting the waste and stabilization agent mixture cure in the field
followed by obtaining (i.e., coring out) samples for testing. The study recommended
that changes be made to allow for the use of the "wet sampling method" for stabilization
verification testing. In the contractor's opinion, field coring the samples introduced
micro-fractures in the samples which resulted in these samples failing the permeability
specification. While the samples collected using the wet sampling method consistently
passed the stabilization specifications, it remains uncertain as to whether samples
collected by this method accurately represent field conditions.
The pilot study estimated that full-scale stabilization would costs at L-ast twice
as much per cubic yard as was estimated by the remedial action contractor. The pilot
study did not address potential stabilization problems in the northern end of the East
Dike or in the North Dike Area where the waste characteristics differ (i.e., the waste is
deeper, contains more municipal solid waste, debris, rubber crumb, and tarry waste).
Additional information regarding the field pilot study can be found in the Final Report
In-Situ Stabilization Pilot Demonstration (McLaren/Hart Environmental Engineering
Corporation and Kiber Environmental Services, Inc., February 1995).
In the summer of 1995, the USEPA requested the BSSC conduct an FFS.
Reasons for conducting the FFS included the previous difficulties in meeting the
project's stabilization specifications and the fact that successful implementation of the
original remedy would, if possible at all, be significantly more difficult, more time-
consuming, and more costly to implement than was contemplated at the time the
original ROD was issued.
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FIGURE 2
SITE MAP
BAILEY WASTE DISPOSAL SITE
ORANGE COUNTY, TEXAS
STAl' IHGH«VAY87
MARSH
APPROXIMATE AREA WHERE
WASTE STABILIZATION WAS
ATTEMPTED
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Activities Associated with the Development of the FFS
The objective of the FFS was to identify if more effective remedies are available
for remediation of the Bailey site. Proposed alternatives were developed as part of the
FFS and compared to the original remedy. In developing the FFS, the BSSC
performed the following tasks:
• activity-specific work plans were prepared and submitted to the USEPA for
review and comment;
• existing site data was reviewed, inventoried, evaluated, and assembled in a
manner that would aid retrieval of data;
• a supplemental site investigation was performed for the North Dike Area of the
site; the resultant data, which differed from what was previously known about
this area, was used to evaluate the technical feasibility of implementing the
original remedial design for the North Dike Area;
• a supplemental site investigation was performed for the North Marsh Area of the
site; the resultant data was used to evaluate: (1) the feasibility of implementing
the original design for this area; (2) other potential remedial alternatives; and (3)
the possibility of addressing the North Marsh Area remediation as an
independent activity that would occur in early 1996;
• a supplemental site investigation was performed for the East Dike Area and Pit
B; the resultant data was used to evaluate the technical feasibility of
implementing the original design for the East Dike Area and the potential
treatment and disposal options for the Pit B wastes; and
• a Focused Feasibility Study Report (GeoSyntec Consultants, September 1996)
was produced that documented the findings of the investigations described
above and presented details of a revised remedial design.
Remedial Activities Implemented During Development of the FFS
Based on the findings of the supplemental investigations performed during the
conduct of the FFS, the following interim actions were taken at the Bailey Waste
Disposal site:
• Approximately 6,000 cubic yards of waste material from the North Marsh Area
were removed and disposed at an offsite industrial waste landfill; this activity
was performed in accordance with the USEPA's Explanation of Significant
Differences for the Record of Decision: Bailey Waste Disposal Superfund Site
(February 1996).
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Approximately 3,000 cubic yards of waste material from Pit A-3 were relocated
and consolidated into the East Dike Area of the site as directed in the original
ROD; and
Approximately 14,000 cubic yards of waste material from Pit B (an area identified
as a "Hot Spot" in the FFS report) were mixed with lime-kiln dust to deactivate
reactive sulfide waste and improve material handling. The resulting non-
hazardous waste was then removed and disposed at an offsite industrial waste
landfill; this activity was performed in accordance with the USEPA's Explanation
of Significant Differences for the Record of Decision: Bailey Waste Disposal Site -
P/fB (May 1996).
1.5 Administrative Record
The Administrative Record is available to the public for review during regular
business hours at the following locations:
U. S. Environmental Nederland Public Library
Protection Agency, Region 6 1903 Atlanta
12th Floor Library Nederland, Texas 77627
1445 Ross Avenue (409) 722-1255
Dallas, TX 75202-2733
(214) 655-6424
Texas Natural Resource Conservation
Commission - Central Records
12118 North I-35, Building D, Room 190
Austin, Texas 78753
(512)239-2920
2.0. REASONS FOR ISSUING A ROD AMENDMENT
2.1 Remedy Selected In ROD
As presented in the original ROD, "the components of the selected remedy
include:
• Relocation of affected sediments from the marsh (North Marsh Area) and
drainage channel, as well as waste from the Drum Disposal Area and Pit A-3, to
the Waste Channel (North Dike Area); and
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• stabilization of the Waste Channel (North Dike Area) and the Area East of
Pond A (East Dike Area) using the technique developed during the remedial
design."
According to the original ROD, the functions of solidification are to "reduce the
mobility of the wastes and provide strength to support a clay cap." The clay cap was to
be installed over the solidified waste. The goais and objectives of the selected remedy
included in the original ROD are "to minimize the potential for waste migration and the
potential for short-term air emissions resulting from remediation"
2.2 Rationale for Changing Remedy Selected in the Original ROD
The major change between the original remedy and the amended remedy is the
removal of the waste stabilization requirement. The capping requirement for the North
and East Dike areas remain. However, the amended remedy calls for the use of a
lightweight composite cap. Components of the lightweight cap include (from bottom to
top) a geosynthetic clay liner, geomembrane, geocomposite drainage layer, protective
drainage layer, protective cover soil layer, and vegetation layer. The original ROD
required a flexible liner, three feet of compacted clay, a protective soil layer, and
vegetation layer. The rationale for changing the remedy selected in the original ROD is
as follows:
• after the numerous in-situ stabilization attempts, subsequent investigations and
a stabilization field pilot study, there are remaining uncertainties regarding the
ability to consistently achieve the project's remedial design stabilization
specifications for major areas of site waste;
• implementation of the original remedy would be significantly more difficult, more
time-consuming, and more costly to implement than was contemplated at the
time the original ROD was issued;
• since the original ROD was issued, activities have been implemented [i.e., the
two Explanations of Significant Differences (ESDs)] which have removed "hot
spots" (i.e., areas with a large percentage of oily, tarry waste with high potential
for continuing and/or future migration into surrounding areas) from the site; and
• based upon the findings of the FFS, the amended remedy is equivalent or
superior in terms of source control, is readily and more quickly implementable,
and is more cost-effective than the designed original remedy.
Please note that during the development of the design for the original remedy,
the flexible liner identified in the ROD was dropped from the final design. During the
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design, it was determined that by successfully stabilizing the waste and covering the
stabilized waste with a three-foot compacted clay cap, the goals of the original ROD
would be achieved without the use of a flexible liner.
2.3. Amended Remedy
Development of this amended remedy is based on the USEPA's request of the
BSSC to conduct the FFS. The overall objectives of the FFS were as follows:
• develop and evaluate remedial alternatives capable of controlling or eliminating
current and/or future human and ecological exposure pathways (i.e., evaluate
alternatives that meets the threshold criteria of protecting human health and the
environment);
• analyze the technical equivalency of the remedial alternatives by comparing the
performance of the remedial alternatives to the original remedial design;
• estimate the cost of the remedial alternatives and schedules needed to
implement the remedy; and
• identify the most cost-effective remedial alternative to control or eliminate current
and/or future human and ecological exposure pathways; consideration would
also be given to the long-term aesthetics, operation and maintenance of the
completed remedy.
The amended remedy calls for remedial action which includes the following
remedy components:
• waste consolidation within the site's waste areas (i.e., East Dike Area, North
Dike Area);
• grading of the waste areas using general fills to provide a mild slope for the base
of the cap and to promote storm water runoff;
• construction of a lightweight composite cap and related appurtenances with
modification as appropriate to satisfy site-specific design criteria and constraints;
• installation of a consolidation water collection system to intercept and remove
groundwater that rises in the short term (i.e., during construction of the cap) due
to consolidation of the waste; this water will be treated using the onsite treatment
facility;
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• installation of storm water management controls to treat storm water runoff from
disturbed areas during construction and to divert storm water runoff away from
inactive or completed areas of the site;
• modifications to existing dikes and side slopes to include adjustment of top
elevations to tie into the cap, repair/modifications of areas that have experienced
excessive settlement, and erosion/slope protection measures; and
• construction and maintenance of access roads.
The amended remedy in combination with the two previous ESDs will provide an
overall site remedy that is protective of hum?»n health and the environment and
complies with Federal and State applicable or relevant and appropriate requirements
(ARARs).
3.0 COMPARATIVE ANALYSIS
A comparative analysis of the original remedy and the amended remedy is
presented in the following sections. Major components including treatment,
containment, groundwater, and general components are discussed. Major ARARs are
also discussed.
3.1 Treatment Components
Original Remedy
The treatment component identified in the original ROD is stabilization.
Stabilization involves mixing site wastes with a reagent such as cement and allowing
the mixture to cure (i.e., harden). The waste/reagent mixture would reduce the mobility
of the wastes and provide strength to support a clay cap. The RD specified that the
onsite wastes would be solidified to a minimum unconfmed compressive strength of 25
pounds per square inch and a hydraulic conductivity of not more than 1x10*
centimeters per second. Implied in these performance requirements is a reduction of
toxicity, or teachability, of the waste.
In the original remedy, surface water which is potentially impacted by the site
waste is treated onsite. The treated water is required to meet the State's discharge
criteria prior to discharge into surrounding surface waters (See Table 1).
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TABLE 1
BAILEY WASTE DISPOSAL SUPERFUND SITE
SURFACE WATER DISCHARGE CRITERIA
TYPE
COMPOUND
ARSENIC
CADMIUM
CHROMIUM
LEAD
MERCURY
SELENIUM
SILVER
PENTACHLOROPHENOL
PHENANTHRENE
OIL & GREASE
24 HR TOXICITY
TOTAL DISSOLVED
SOLIDS (TDS)
VOLATILE ORGANIC
COMPOUNDS (VOC)
TOTAL ORGANIC
CARBON (TOC)
PH
DISCHARGE CRITERIA
COMPOSITE SAMPLE
(mg/l)
GRAB SAMPLE
(mg/l)
0.2
0.1
0.2
0.5
0.01
0.2
0.1
1.23
0.62
-
50%
SURVIVAL
13,000
<1.0
15
6-9
0.4
0.2
0.4
1.0
0.02
0.4
0.2
2.60
1.32
15
50%
SURVIVAL
15,000
<1.0
30
6-9
NOTE: These criteria were developed by the TNRCC based upon the fact that the water will be discharged
into a tidally influence pond (Pond A). The pond is large enough to allow for a 200-foot mixing
zone. The volume, frequency and period of discharge were also considered. Above is a list of
specific constituents which were evaluated and the concentrations that will meet the Texas Surface
Water Quality Standards (TSWQS)(30 TAG § 307).
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Amended Remedy
With respect to the amended remedy, there is no specified waste treatment
component. There has been some soil conditioning in isolated areas within the North
Dike and East Dike. These isolated areas, which have been found to be soft and
unable to support heavy construction equipment, have been mixed with lime to provide
ground strength improvement. Such ground strength improvement is necessary for the
installation of the cap. Operation of the existing onsite water treatment plant will
continue during construction of the amended remedy to treat potentially contaminated
surface water and consolidation water collected during cap construction.
3.2 Containment Components
Original Remedy
The containment component identified in the original ROD was a cap. As
presented in the original ROD, "The cap would consist of a flexible liner and a minimum
3 feet of compacted day.' Functions of the cap include:
• prevent direct contact by humans and wildlife with the wastes and affected soils;
• limit direct contact by precipitation with the wastes and affected soils;
• prevent storm water runoff with the wastes and affected soils;
• control the generation of leachable liquids from the waste; and
• control the migration of site contaminants through groundwater, surface water,
soil, and air pathways.
Amended Remedy
The amended remedy includes the use of a lightweight composite cap.
Components of the lightweight cap include the following layers:
• General Clean Fill Layer - will be placed on the existing grade to provide a
uniform surface for the overlying layers and to provide a slight slope to the cap
for storm water control;
• Geocomposite Gas Venting Layer - gas venting layer will consist of a 10- to 15-ft
wide strip of geocomposite placed along the ridge of the cap;
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• Geosynthetic Clay Liner - maximum allowable hydraulic conductivity will be
equal to or less than 1 x 10'7 cm/s;
• Geomembrane - material will be high density polyethylene (HOPE) with a
minimum thickness of 60 mils;
• Drainage Layer Geocomposite - water within this layer will be gravity
discharged;
• Protective Soil Layer - to protect geosynthetic layers from ultraviolet radiation
and temperature extremes;
• Vegetation Layer - selected grasses to limit erosion of the protective soil layer.
The functions of the lightweight cap are the same as those of the original remedy
cap. However, n i comparison to the designed remedy clay cap, the lightweight
composite cap will allow less vertical infiltration (please note that the designed cap
differed from the cap described in the original ROD in that the designed cap was a
three-foot compacted clay cap, and did not have the flexible liner). The lightweight cap
will need to be maintained in a similar manner as the original remedy cap, but will
require less maintenance since desiccation of the clay layer will not occur. Since a
majority of the underlying waste and affected soils will not be stabilized, the
"lightweight" aspect of the amended remedy cap is essential. By being "lightweight,"
less consolidation of the waste will occur thereby reducing the quantity of liquids which
will be squeezed from the waste and into the surrounding soil formation. Also, it should
be noted that the amended remedy incorporates a consolidation water collection
system designed to capture, treat, and discharge consolidation water produced during
cap construction.
The lightweig. it cap will be tied into native low permeable soils. Based on a
review of data found on the hydraulic conductivity values for the soils at the site, the
hydraulic conductivities of the soils beneath the waste are on the order of 10'7 to 10"*
centimeters per second. The Rl describes the underlying soils beneath the waste as
Very soft gray clay to silty day* that typically extends to a depth of 25 to 35 feet. This
thickness of material provides adequate containment to underlying layers. In addition,
the bottom portions of the dikes that contain the waste (an approximate depth of five to
ten feet) consist of undisturbed native soil that should have a similar hydraulic
conductivity to the soil beneath the waste. Vertical and lateral migration of water
through the dikes is expected to be negligible since the waste is essentially contained
in place by the low permeability soils beneath and adjacent to the waste, and there is
no evidence to suggest that an appreciable hydraulic gradient exists across the dikes
that contain the waste. Long-term operation and maintenance will be conducted to
ensure the integrity of the cap consistent with 40 C.F.R. §264.117 (Post closure care
and use of property).
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3.3 Groundwater Components
Original Remedy
The original ROD contained no groundwater remedy components. The site's
remedial investigation concluded the following: the site has had no impact on drinking
water; and in the unlikely event that site constituents were to migrate via a groundwater
pathway, it would take more than 800 years for them to reach potable groundwater.
The shallow groundwater beneath and adjacent to the site is saline and not suitable for
human consumption.
Amended Remedy
The amended remedy does not contain any long-term groundwater remedy
components. In the short-term (i.e., during the construction of the cap), installation of a
consolidation water collection layer to intercept and remove groundwater that rises due
to the consolidation of the waste will be used. The consolidation water collection layer
will be installed before the placement of the general clean fill layer and will consist of a
series of perforated pipes placed in the bottoms of gravel filled trenches. The
perforated pipes, which would be installed at or slightly above the groundwater table,
would convey consolidation water to collection sumps. This water would then be
pumped to the existing wastewater holding tank, treated to the current discharge limits,
if necessary, and discharged. After placement of the general fill layer and prior to the
placement of the remaining cap components, the sumps would be removed and
backfilled.
3.4 General Components
Original Remedy
The general components in the original remedy include:
• consolidation of site waste within the main waste areas - East Dike Area and
North Dike Area;
• consolidation of site debris and cleared vegetation into the main waste areas;
• site preparation and installation of office, storage, and security facilities;
• installation of storm water management controls to treat storm water runoff from
disturbed areas during construction and to divert storm water runoff from inactive
areas of the site;
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• installation of erosion/slope protection measures; and
• construction and maintenance of access roads.
The original ROD estimated the time to implement the remedy as 14 months. In
1992 the remedial action contractor estimated it would take 18 months to implement the
original remedy. In 1995 the BSSC estimated that a 24-month remediation schedule
would be required to complete the original remedy. However, the BSSC was not
certain as to whether it would be able to consistently achieve the stabilization
performance standards.
Amended Remedy
The general components of the amendod remedy include the general
components of the original remedy plus the following components:
• modification of previously constructed East Dike Area flood control dikes
(modifications will include adjustment to top elevations, repair/modifications of
areas that have experienced excessive settlement or failure); and
• modifications to the existing North Dike Area dikes and side slopes (i.e.,
adjustment of top elevations as necessary to tie into the cap).
The estimated time to construct the amended remedy is one year.
3.5 Malor Applicable or Relevant and Appropriate Requirements iARARs)
CERCLA, Section 121(d)(2) requires remedial actions to at least attain
applicable or relevant and appropriate requirements (ARARs). Applicable
requirements are those cleanup standards, standards of control, and other substantive
environmental protection requirements, criteria, or limitations promulgated under
Federal or State law that specifically address a hazardous substance at a Superfund
site. Relevant and appropriate requirements are standards which address problems or
situations sufficiently similar to those encountered at the CERCLA site which warrant
their use.
The original ROD identified the following ARARs for the selected remedy:
• 40 CFR 264.18(b) (RCRA) - Facilities in 100-year floodplain must be designed,
constructed, operated and maintained to avoid washouts.
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• Executive Order 11988 (Floodplain Management) - Action taken must avoid
adverse effects and minimize potential harm to surrounding area.
• 40 CFR 264 (RCRA) - Construction requirements for hazardous waste storage
facilities.
The ARARs identified above are also applicable or relevant and appropriate for
the amended remedy. While not identified in the original ROD, the existing surface
water discharge criteria are based upon meeting the Texas Surface Water Quality
Standards (TSWQS)(30 TAG § 307). The lightweight composite cap will be designed
and constructed to meet the substantive guidance of the USEPA for a RCRA Subtitle C
facility (USEPA, Design and Construction of RCRA/CERCLA Final Covers, May 1991)
with modification as appropriate to satisfy site-specific design criteria and constraints,
including criteria to satisfy the "lightweight" criterion. For example, the lightweight
composite cap will be designed and constructed to:
• provide long-term minimization of migration of liquids through the cap;
• function with minimum maintenance;
• promote drainage and minimize erosion or abrasion of the cover;
• accommodate settling and subsidence so that the cover's integrity is maintained;
and
• have a permeability less than or equal to the permeability of the natural subsoils
present.
After construction, requirements for the lightweight cap will include:
• maintaining the integrity and effectiveness of the final cover, including making
repairs to the cap as necessary to correct the effects of settling, subsidence,
erosion, or other events;
• preventing run-on and runoff from eroding or otherwise damaging the final cover.
4.0. EVALUATION OF ALTERNATIVES
The USEPA uses nine criteria, or standards, to evaluate alternatives for
addressing a Superfund site. These nine criteria are categorized into three groups:
threshold, primary balancing, and modifying. The threshold criteria must be satisfied in
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order for an alternative to be eligible for selection. The primary balancing criteria are
used to weigh major tradeoffs among alternatives. The modifying criteria are taken into
account after public comment is received on the Proposed Plan of Action. A
description of each of the nine criteria is presented below.
4.1 Threshold Criteria
Overall Protection of Human Health and Environment
This criterion addresses the way in which a potential remedy would reduce,
eliminate, or control the risks posed by the site to human health and the environment.
The methods used to achieve an adequate level of protection may be through
engineering controls, treatment techniques, or other controls such as restrictions on the
future use of the site. Total elimination of risk is often impossible to achieve. However,
a remedy must minimize risks to assure that human health and environment are being
protected.
Compliance with ARARs
Compliance with ARARs, or "applicable or relevant and appropriate
requirements," assures that a selected remedy will meet all related Federal, state, and
local requirements. The requirements may specify maximum concentrations of
chemicals that can remain at the site; design or performance requirements for
treatment technologies; and restrictions that may limit potential remedial activities at a
site because of its location.
4.2 Primary Balancing Criteria
Long-term Effectiveness and Permanence
This criterion address the ability of a potential option to reliably protect human
health and the environment over time, after the remediation goals have been
accomplished.
Reduction of Toxicitv. Mobility, or Volume of Contaminants
This criterion assess how effectively a proposed remedy will address the
contamination problem. Factors considered include the nature of the treatment
process; the amount of hazardous materials that will be destroyed by the treatment
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process; how effectively the process reduces the toxicity, mobility, or volume of waste;
and the type and quantity of contamination that will remain after treatment.
Short-term Effectiveness
This criterion addresses the time required to implement the remedy. Remedies
often require several years for implementation. A potential remedy is evaluated for the
length of time required for implementation and the potential impact on human health
and the environment during implementation.
Implementabilitv
This criterion addresses the ease with which a potential remedy is put in place.
Factors such as availability of materials and services are considered.
Cost
This criterion includes capital costs required for design and construction, and
projected long-term maintenance costs. Cost is considered and compared to the
benefit that will result from implementing the remedy.
4.3 Modifying Criteria
State Acceptance
The state has the opportunity to review the RI/FS, the FFS, and other key
documents and offer comments to the USEPA, The state concerns that are assessed
under this criterion include the state's position and key concerns related to the
proposed amendment, and state comments on ARARs or the proposed use of waivers.
Community Acceptance
During the public comment period, interested persons or organizations may
comment on the potential remedies. The USEPA considers these comments in making
its final selection. The comments are addressed in a document called a
responsiveness summary.
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4.4 NINE CRITERIA EVALUATION
For the purpose of this ROD Amendment, the term "remedial alternatives" refers
to technologies, administrative or legal actions, or other possible solutions for
addressing contamination problems at the Bailey Superfund site. The remedial
alternatives originally considered for the Bailey Waste Disposal site are described in
detail in the Feasibility Study Report (Engineering Science, April 1988). A recent
evaluation of the remedial alternatives is described in detail in the Focused Feasibility
Study Report (GeoSyntec Consultants, August 1996). The comparison of the original
remedy to the amended remedy is discussed in the following sections.
4.4.1. Overall Protection of Human Health and the Environment
The original selected remedy would effectively isolate and prevent direct contact
by humans and wildlife with site waste. Stabilization of the waste would reduce the
mobility of some waste constituents. Modeling performed during the focused feasibility
study indicated that infiltration of precipitation through the designed cap and into the
waste would occur during the anticipated life of the cap. As stated previously in
Section 2.2, the designed cap differed from the cap described in the original ROD in
that the final cap design did not include the flexible liner. As a result of infiltration
through the cap, constituents of concern could be mobilized from the stabilized waste,
as evidenced by the toxicity characteristic leaching procedure test (an analytical test
method) results presented in the Feasibility Study Report (Engineering Science, April
1988) and the Stabilization Evaluation Report (Harding Lawson Associates, November
1991). However, there is no evidence to suggest that waste constituents have
migrated from the site via the groundwater pathway.
Implementation of the original remedy would provide additional protection
compared to existing conditions by eliminstting the direct contact and storm water runoff
exposure pathways. There would also be no opportunity for uptake of isolated wastes
into biota and, therefore, no creation of consumptive exposure pathways. During the
implementation of the original remedy, the atmospheric release of volatile organics and
participates can occur due to waste disturbance, solidification activities, and general
earth moving activities. Air monitoring would be required, and control measures would
have to be implemented to provide worker and community protection during
implementation.
The amended remedy would also effectively isolate waste and prevent direct
contact by humans and wildlife with site wastes. It should be noted that less waste
now exists on the site than was the case at the time the original remedy was selected.
Pursuant to ESDs, interim remedial actions (i.e., excavation and offsite disposal of "hot
spots" - Pit B and North Marsh Area Waste) have occurred. Modeling performed
during the focused feasibility study indicated that the lightweight composite cap will
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perform better than the original cap and will essentially eliminate infiltration. However,
the load of the general fill and protective cover soil will result in consolidation of waste
and production of consolidation water. Based on the modeling, the consolidation
process should occur within a relatively short period of time (i.e., during construction
period or shortly thereafter). During the construction period, a temporary consolidation
water management system will be implemented to collect the consolidation water for
treatment at the site's existing water treatment plant.
Implementation of the amended remedy would provide additional protection
compared to existing conditions by eliminating the direct contact exposure pathway,
eliminating the storm water runoff exposure pathway, and by limiting the generation and
release of teachable liquids from the waste and therefore protecting the groundwater
pathway. There would also be no opportunity for uptake of isolated wastes into biota
and therefore no creation of consumptive exposure pathways. During the
implementation of the amended remedy, the atmospheric release of volatile organics
and particulates can occur due to waste disturbance and general earthmoving
activities. Air monitoring would be required, and control measures may have to be
implemented to provide worker and community protection during implementation of the
amended remedy. The amended remedy will meet the site goals and objectives of
remedial action by minimizing the potential for waste migration and the potential for
short-term air emissions resulting from remediation while being more cost-effective and
quicker to implement than the original remedy.
4.2.2. Compliance With Applicable Relevant and Appropriate Requirements
(ARARsl
The amended remedy will be performed in full compliance with all chemical,
location, and action-specific ARARs and other criteria, advisories and guidelines which
are applicable (i.e., surface water discharge limits established by the TNRC/C) or
considered relevant and appropriate. ARARs are identified in Section 3.5 (Major
Applicable or Relevant and Appropriate Requirements). The lightweight composite
cap will be designed to meet the substantive recommendations of the USEPA for a
RCRA Subtitle C facility with modification as appropriate to satisfy site-specific design
criteria and constraints, including criteria to satisfy the "lightweight" criterion.
The USEPA, after conferring with the TNRCC, has previously invoked an Interim
Measure ARAR Waiver (as authorized by CERCLA § 121 (d)(4)(A)) of 40 CFR
264.18(b) (RCRA - Facilities in a 100-year floodplain) for previous East Dike Area and
Pit B work. The need to invoke such an ARAR waiver in the future will be evaluated on
a case by case basis.
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4.4.3. Long-term Effectiveness and Permanence
The original remedy provides for long-term effectiveness and permanence
through stabilization of site wastes. Stabilization of waste is typically effective at
reducing the mobility of inorganic compounds such as metals in soils and sludges.
However, as previously discussed, efforts to stabilize waste at the Bailey site have not
been successful. The addition of a containment remedy component (i.e., the cap)
provides additional effectiveness. To achieve long-term effectiveness the cap would
need to be maintained to prevent desiccation and/or settlement cracking, penetration
by plant roots, or erosion which would decrease the integrity of the clay layer.
The amended remedy will effectively and permanently address the site wastes
by constructing and maintaining a lightweight composite cap. As previously noted, less
waste now exists on the site due to "hot spot" removal and offsite disposal than was the
case at the time the original ROD was selected. Lightweight composite caps are very
effective at limiting infiltration and preventing direct exposure of humans and wildlife to
the waste. The incorporation of ah HOPE geomembrane into the capping system
provides protection to underlying components from the effects of desiccation, thus
reducing degradation of the cap over time. Modeling conducted during the focused
feasibility study predicted that infiltration through the cap to be negligible and that the
cap will not cause significant long-term consolidation problems. To achieve long-term
effectiveness, it will be necessary to maintain the integrity and effectiveness of the final
cover, including making repairs to the cap as necessary to correct the effects of
settling, subsidence, erosion, or other events.
4.4.4. Reduction of Toxicitv. Mobility, or Volume Through Treatment
The original remedy included stabilization as a major treatment component.
Stabilization of the waste would reduce the mobility of some waste constituents -
primarily metals and to a lesser extent volatile and semivolatile compounds. The
toxicity of leachate from the waste would also be reduced by stabilization. However, it
should be noted that the toxicity of the waste is not reduced by stabilization (see
Stabilization Evaluation Report, Harding Lawson, February 1991). Stabilization would
also improve the soil strength thereby help to support the clay cap. However, the
addition of stabilization reagents would result in an increase in the volume of waste.
The amended remedy does not include a waste treatment component.
However, the mobility of waste constituents is significantly reduced in the long term by
source control since infiltration into the waste is essentially eliminated. During the
construction of the cap, groundwater that rises due to the consolidation of the
unstabilized waste under the cap will be collected and treated at the onsite wastewater
treatment plant.
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4.4.5. Short-term Effectiveness
Implementation of either remedy will require measures to limit direct exposure of
workers to site waste and fugitive emissions. Control measures will include the use of
dust suppression, the use of appropriate personal protection equipment, and the use of
equipment and personnel decontamination facilities in limiting exposure. These control
measures, together with perimeter air monitoring, will provide adequate protection to
the community during construction. Both alternatives require installation of storm water
management controls to treat water from disturbed areas during construction and to
divert storm water runoff away from inactive or completed areas of the site.
The amended remedy will result in less waste disturbance and, hence, less
potential for contamination of surface water. There will be a short-term increase in the
mobility of the waste constituents due to consolidation of the waste under the imposed
load of the cap and the related consolidation water. However, installation of a
consolidation water collection system and continuation of existing surface-water
management measures during remedy implementation will mitigate these effects.
Implementation of the original remedy would involve the disturbance of large
volumes of waste. The estimated time to implement the original remedy is two years.
The amended remedy will require less disturbance of waste and therefore results in
lower risks to site workers. The estimated time required to implement the amended
remedy is one year.
4.4.6. Implementabilitv
The original remedy, as discussed in Section 2.2 (Rationale for changing
remedy selected in the original ROD), will, at best, be significantly more difficult to
implement than was contemplated at the time the original ROD was issued. After
several years of studies, investigations, and numerous attempts to implement
stabilization, there are still remaining uncertainties regarding the ability to achieve the
project's stabilization specifications for major waste areas of the site.
The amended remedy (i.e., a lightweight composite cap) can be implemented
using conventional equipment and readily available materials. The anticipated
settlements and corresponding strains induced in the cap components can be
accommodated usinq conventional design techniques and construction materials. The
use of lightweight composite caps is well established as a reliable process option for
source control.
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4.4.7. Cost
The estimated cost to complete implementation of the original remedy is $35.4
million. This estimate is considerably more than the original 1988 ROD estimate of
$13.7 million. The present day estimated costs are based on bids obtained for the
original remedial action. These bids have been adjusted to account for additional items
of work identified during the original remedial action, increases in quantities and unit
rates that were identified during the original remedial action, and increases in
construction price indices from the original 1992 bid date to 1996.
To date, more than an estimated $18 million have been expended in site
remedial cost. The amended remedy is estimated to require an additional expenditure
of $12 million to complete. Therefore, the estimated cost to complete implementation of
the amendedjemedy is $30 million.
4.4.8. State Acceptance
The TNRCC was provided a draft copy of the proposed ROD Amendment for
review and comment. In a response dated September 10,1996 the TNRCC stated,
"Overall, the TNRCC approves of the remedy presented in the draft Record of Decision
(ROD) Amendment." The TNRCC also provided comments on the draft which have
been incorporated into this ROD Amendment.
4.4.9. Community Acceptance
The USEPA recognizes that the community in which a Superfund site is located
is the principal beneficiary of all remedial actions undertaken. The USEPA also
recognizes that it is its responsibility to inform interested citizens of the nature of
Superfund environmental problems and solutions, and to leam from the community
what its desires are regarding these sites. The proposed ROD Amendment was
released for public comment in October 1996. The public comment period began on
October 16,1996 and ended on November 14,1996. A public meeting was held on
October 17, 1996 at a location near the site to provide the local community an
opportunity to provide verbal and/or written comments on the proposed ROD
Amendment. A court reporter was present to record a transcript of the meeting.
During the public comment period, no verbal or written comments on the proposed
ROD Amendment were received.
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5.0. STATUTORY DETERMINATIONS
The USEPA's primary responsibility at Superfund sites is to select remedial
actions that are protective of human health and the environment. Section 121 of
CERCLA also requires that the selected remedial action for the site comply with
applicable or relevant and appropriate environmental standards established under
Federal and State environmental laws, unless a waiver is granted. The selected
remedy must also be cost-effective and utilize permanent treatment technologies or
resource recovery technologies to the maximum extent practicable. The statute also
contains a preference for remedies that include treatment as a principal element. The
following sections discuss how the amended remedy for contaminated source areas at
the Bailey site measures up to the statutory requirements.
5.1 Protection of Human Health and the Environment
In order to protect human health and the environment, the amended remedy will
effectively isolate the waste and prevent direct contact by humans and wildlife with site
waste by the construction of a lightweight composite cap. Modeling has shown that the
lightweight composite cap will essentially eliminate infiltration into the waste material
thereby limiting the generation and release of teachable liquids from the waste.
5.2 Attainment of Applicable or Relevant and Appropriate Requirements of
Environmental Laws
The amended remedy will be performed in full compliance with all chemical,
location, and action-specific ARARs and other criteria, advisories and guidelines which
are applicable (i.e., surface water discharge limits established by the TNRCC) or
considered relevant and appropriate. ARARs are identified in Section 3.5 (Major
Applicable or Relevant and Appropriate Requirements).
5.3 Cost Effectiveness
The USEPA believes that the amended remedy is cost-effective in mitigating the
principal threat waste at the site. Section 300.430(f)(ii)(D) of the NCP requires the
USEPA to determine cost-effectiveness by evaluating the following three of the five
balancing criteria to determine overall effectiveness: long-term effectiveness and
permanence, reduction of toxicity, mobility or volume through treatment, and short-term
effectiveness. Overall effectiveness is then compared to cost to ensure that the
remedy is cost effective. Environmental soundness will consider overall effectiveness:
long-term effectiveness and permanence, reduction of toxicity, mobility or volume
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through treatment, and short-term effectiveness. To date, more than an estimated $18
million have been expended in the site remedial cost. The amended remedy is
estimated to require an additional expenditure of $12 million.
5.4 Utilization of Permanent Solutions and Alternative Treatment Technologies
or Resource Recovery Technologies to the Maximum Extent Practical
As explained above, the amended remedy represents a permanent solution to
the maximum extent practical which can be utilized in a cost-effective manner for the
Bailey site. The USEPA is certain that the amended remedy will provide the best
balance in considering long-term effectiveness and permanence; reduction in toxicity,
mobility or volume through treatment; short-term effectiveness; implementability; and
cost, as well as considering the statutory preference for treatment as a principal
element and considering State and community acceptance.
The TNRCC was provided a draft copy of the proposed ROD Amendment for
review and comment. In a response dated September 10,1996 the TNRCC stated,
"Overall, the TNRCC approves of the remedy presented in the draft Record of Decision
(ROD) Amendment." The TNRCC also provided comments on the draft which have
been incorporated into this ROD Amendment.
The proposed ROD Amendment for the Bailey Waste Disposal site was released
for public comment in October 1996. The public comment period began on October 16,
1996 and ended on November 14, 1996. A public meeting was held on October 17,
1996 at a location near the site to provide the local community an opportunity to
provide verbal and/or written comments on the proposed ROD Amendment. A court
reporter was present to record a transcript of the meeting. In addition to court reporter,
the USEPA personnel, and TNRCC personnel, 12 persons attended the public meeting.
No verbal comments on the proposed ROD Amendment were received during the
public meeting. Additionally, no written comments on the proposed ROD Amendment
were received during the public comment period.
5.5 Preference for Treatment as a Principal Element
The amended remedy will not satisfy the statutory preference for treatment as a
principal element. The reasons for eliminating the treatment component of the original
ROD are discussed in Section 2.2 (Rationale for Changing Remedy Selected in the
Original ROD). There has been some soil conditioning in isolated areas within the East
Dike and North Dike Areas. These isolated areas, which were found to be soft and
unable to support heavy construction equipment, were mixed with lime to provide
ground strength improvement. Such ground strength improvement is necessary for
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installation of the lightweight cap. Additionally, during the construction of the cap,
groundwater that rises due to the consolidation of the unstabilized waste under the cap
will be collected and treated at the onsite wastewater treatment plant.
Because the amended remedy will result in hazardous substances remaining
onsite, a review will be conducted five years after commencement of remedial action to
ensure that the remedy continues to provide adequate protection of public health,
welfare and the environment.
M DOCUMENTATION OF SIGNIFICANT CHANGES
Because no written or verbal comments were received during the public
comment perjod, the USEPA determined that no significant changes to the proposed
ROD Amendment were necessary.
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