PB98-964203
EPA 541-R98-163
March 1999
EPA Superfund
Record of Decision:
Madison Creosote Works, Inc.
Madison ville, LA
8/25/1998
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RECORD OF DECISION
MADISONVILLE CREOSOTE WORKS SUPERFUND SITE
MADISONVILLE / ST. TAMMANY PARISH, LOUISIANA
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION 6
SUPERFUND DIVISION
*
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o
AUGUST 1998
106
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TABLE OF CONTENTS
RECORD OF DECISION 1
TABLE OF CONTENTS 2
LIST OF ACRONYMS 5
CONCURRENCE PAGE 7
USEPA PEER REVIEW ..8
THE DECLARATION 9
SITE NAME AND LOCATION 9
STATEMENT OF BASIS AND PURPOSE 9
ASSESSMENT OF THE SITE 9
DESCRIPTION OF SELECTED REMEDY 9
STATUTORY DETERMINATIONS 10
DATA CERTIFICATION CHECKLIST 11
AUTHORIZING SIGNATURE 11
THE DECISION SUMMARY 12
INTRODUCTION 12
SITE NAME, LOCATION, AND DESCRIPTION 12
FIGURE I: MCW SITE MAP 15
SITE HISTORY 16
FIGURE 2: FORMER ON-SITE STRUCTURES 18
USEPA SUPERFUND HISTORY 19
COMMUNITY PARTICIPATION 21
SCOPE AND ROLE OF RESPONSE ACTION 23
SUMMARY OF SITE CONTAMINATION 24
FIGURE 3A: EXTENT OF ON-SITE AND NORTH OFF-SITE CONTAMINATION 26
FIGURE 3B: EXTENT OF SOUTH OFF-SITE CONTAMINATION 27
FIGURE 3C: EXTENT OF DNAPL PLUME CONTAMINATION 28
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TABLE OF CONTENTS (Continued)
CURRENT AND POTENTIAL FUTURE SITE AND RESOURCES USES 29
SITE RISKS 30
EXPOSURE PATHWAY SCENARIOS 30
CHART 1: SITE EXPOSURE CONCEPTUAL MODEL 31
RISK CHARACTERIZATION 32
TABLE 1: SUMMARY OF CHEMICALS AND EXPOSURE ROUTES EXCEEDING LIFETIME
CANCER RISK OF 1E-06 35
TABLE 2: SUMMARY OF CHEMICALS AND EXPOSURE ROUTES EXCEEDING HAZARD INDEX
OF 1.0 41
FORMULATION OF CLEANUP ACTION LEVELS 46
TABLE 3: CALCULATED BENZO(A)PYRENE CLEANUP ACTION LEVEL CONCENTRATIONS 49
REMEDIATION OBJECTIVES 50
DESCRIPTION OF REMEDIAL ALTERNATIVES 54
ALTERNATIVE 1: NO FURTHER ACTION 55
ALTERNATIVE 2: INSTITUTIONAL CONTROLS / GROUND WATER MONITORING 55
ALTERNATIVE 3: LOW TEMPERATURE THERMAL DESORPTION & DNAPL RECOVERY TRENCH
SYSTEM 56
ALTERNATIVE 4: INCINERATION & DNAPL RECOVERY TRENCH SYSTEM 56
ALTERNATIVE 5: SOLIDIFICATION / STABILIZATION & DNAPL RECOVERY TRENCH SYSTEM 57
ALTERNATIVE 6: CAPPING & DNAPL RECOVERY TRENCH SYSTEM 58
ALTERNATIVE 7: LANDFILL DISPOSAL & DNAPL RECOVERY TRENCH SYSTEM 59
OSHA REQUIREMENTS 59
COMPARATIVE ANALYSIS OF REMEDIAL ALTERNATIVES / STATUTORY DETERMINATIONS 60
THRESHOLD CRITERIA 60
PRIMARY BALANCING CRITERIA 64
MODIFYING CRITERIA 65
TABLE 4: COMPARATIVE ANALYSIS OF ALTERNATIVES 67
SELECTED REMEDY 72
FIGURE 4: LOW TEMPERATURE THERMAL DESORPTION PROCESS FLOW DIAGRAM 73
FIGURE 5: DNAPL RECOVERY TRENCH SYSTEM 74
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TABLE OF CONTENTS (Continued)
ANALYSIS OF THE SELECTED CLEANUP ALTERNATIVE (ALTERNATIVE #3) 75
TABLE 5: COST ESTIMATE FOR THE SELECTED REMEDY 77
REASONS OTHER ALTERNATIVES WERE NOT SELECTED 84
RESPONSIVENESS SUMMARY 85
STAKEHOLDER ISSUES AND USEPA RESPONSES 85
APPENDIX: SITE ADMINISTRATIVE RECORD INCLUDING COMMUNITY AND STATE ACCEPTANCE
LETTERS 88
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LIST OF ACRONYMS
ARAR
ATSDR
BAP
BGS
CERCLA
CFR
COC
CTE
DNAPL
DOI
EPS
FS
HI
HQ
LAC
LDEQ
LDNR
LOPH
LRS
LSWR
LTTD
MCL
MCW
MWP
NOAA
NPDES
O&M
OSHA
Applicable or Relevant and Appropriate Requirement
Agency For Toxic Substance And Disease Registry
Benzo(a)pyrene
Below Ground Surface
Comprehensive Environmental Response, Compensation, and Liability Act
Code of Federal Regulations
Chemicals of Concern
Central Tendency Exposure
Dense Non-Aqueous Phase Liquids
Department of the Interior
Exposure Pathway Scenario
Feasibility Study
Hazard Index
Hazard Quotient
Louisiana Administrative Code
Louisiana Department of Environmental Quality
Louisiana Department of Natural Resources
Louisiana Office of Public Health
Louisiana Revised Statutes
Louisiana Solid Waste Regulations
Low Temperature Thermal Desorption
Maximum Contaminant Level
Madisonville Creosote Works
Madisonville Wood Preserving Company, Inc.
National Oceanic and Atmospheric Administration
National Pollution Discharge Elimination System
Operation and Maintenance
Occupational Safety and Health Administration
PAH
Polynuclear Aromatic Hydrocarbon
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LIST OF ACROYNMS (Continued)
RA Remedial Action
RAO Remedial Action Objective
RCRA Resource Conservation and Recovery Act
R£L Recommended Exposure Level
R] Remedial Investigation
RME Reasonable Maximum Exposure
ROD Record Of Decision
SARA Superfund Amendments and Reauthorization Act
SH22 State Highway 22
Site Superfund Site
TAP Toxic Air Pollutant
ULCR Upperbound Lifetime Cancer Risk
USEPA United States Environmental Protection Agency
USF&W United States Fish and Wildlife Service
USGS United States Geological Survey
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CONCURRENCE PAGE
L
7 Stephen L. Tzhone^
Remedial Project Manager
Wren I>. StengV Chief
Louisiana Projects M^ragement Section
Carl E. Edlund, Chief
Louisiana / New Mexico Branch
Mark A. Peycl^e, Chief
Litigation And Enforcement Branch
yron O. Knudson, P.E., Director
Superrund Division
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USEPA PEER REVIEW
Cl***>«U-^
sky j
M!att Charsky
USEPA Headquarters
Janinejpinan
USEPA Headquarters
WV/vU ,
JOT n C. Meyer
Remedial Project
iager
Chris G. Villarreal
Remedial Project Manager
Jon D. Rauscher, Ph.D.
Toxicologist
f. Charters, Ph.D.
Toxicologist
RCRA Enfrcement fficer
D. Bruce Jones /
Office of Regiona^ounsel
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THE DECLARATION
SITE NAME AND LOCATION
Madisonville Creosote Works Superfiind Site.
Madisonville / St. Tammany Parish, Louisiana.
STATEMENT OF BASIS AND PURPOSE
This decision document presents the selected Remedial Action (RA) for the Madisonville
Creosote Works (MCW) Superfund Site (Site), in St. Tammany Parish, Louisiana, which 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).
This decision is based on the Administrative Record for the MCW Site and has the concurrence
of both the State of Louisiana and St. Tammany Parish (see APPENDIX).
ASSESSMENT OF THE SITE
Actual or threatened releases of hazardous substances from this Site, if not addressed by
implementing the response action selected in this Record of Decision (ROD), may present an
imminent and substantial endangerment to public health, welfare, or the environment.
DESCRIPTION OF SELECTED REMEDY
This ROD addresses the contamination in the soil, sediment, surface water and ground water at
the Site by:
Low Temperature Thermal Desorption (LTTD) to address the principal threat wastes within
the soil and sediment (thus eliminating the source of contamination for surface water);
Dense Non-Aqueous Phase Liquids (DNAPL) Recovery Trench System to contain and
recover low level threat wastes within the ground water;
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Institutional controls to ensure that future individuals will not be exposed to remaining low
level Site contaminants during its containment and recovery; and,
Ground Water monitoring to ensure the effectiveness of the cleanup remedy.
The overall Site cleanup strategy is to clean up the MCW Site such that the areas of concern are
made safe for residential and recreational usage.
The LTTD component of the cleanup remedy will address the principal threats wastes at the
MCW Site. Cleanup of creosote liquid source materials located in approximately 75,000 cubic
yards of contaminated soil and sediment removes this principal threat to human health and the
environment and satisfies the statutory preference for treatment of such substances.
The DNAPL Recovery Trench System will contain and recover the low-level threats at the MCW
Site. Containment and recovery of the low teachability creosote source materials within the
shallow clayey-silt saturated zone, approximately 15-25 feet below ground surface, will prevent
any migration of contaminants into the viable aquifers and reduce and/or eliminate the source
contaminants.
These components plus institutional controls ensure that future individuals will not be exposed to
the Site contaminants. Data from ground water monitoring will reflect the effectiveness of this
remedy over time.
STATUTORY DETERMINATIONS
The selected remedy is protective of human health and the environment, complies with Federal
and State requirements that are legally applicable or relevant and appropriate to the RA, and is
cost effective. This remedy utilizes permanent solutions and resource recovery technologies to
the maximum extent practicable for the MCW Site.
The LTTD component of the cleanup remedy will address the source of contamination,
approximately 75,000 cubic yards of contaminated soil and sediment, thereby, removing the
principal threat to human health and the environment and satisfying the statutory preference for
treatment as a principal element of the remedy.
Because this remedy will result in hazardous substances remaining on the MCW Site (low
teachability creosote source materials within the shallow clayey-silt saturated zone) above levels
that allow for unlimited use and unrestricted exposure, a review will be conducted within five
years of initiation of RA to ensure that the remedy continues to provide adequate protection of
human health and the environment.
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DATA CERTIFICATION CHECKLIST
Title ROD contains information and addresses the Site chemicals of concern (COCs) and their
respective concentrations; baseline risk represented by the COCs; cleanup levels established for
COCs and the basis for the levels; current and future land use assumptions from the baseline risk
assessment; land use that will be available at the Site as a result of the selected remedy; estimated
capital, operation and maintenance (O&M), and total present worth costs and discount rate,
including, the number of years over which the remedy cost estimate is projected; and, decisive
factors that led to selecting the remedy.
AUTHORIZING SIGNATURE
Date
Regional Adinistrator
U.S. Environmental Protection Agency
Region 6
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THE DECISION SUMMARY
INTRODUCTION
The United States Environmental Protection Agency (USEPA) presents the following Record Of
Decision for addressing hazardous substance contamination at the MCW Site St. Tammany
Parish, Louisiana. This ROD addresses the Site as a whole and is the final action for all areas of
the Site by recommending treatment of contaminated soil and sediment by LTTD and
containment and recovery of contaminated ground water by the DNAPL Recovery Trench
System. Once the long-term remedial action is operational, USEPA will pursue the Site's
deletion from the National Priorities List (NPL) of Superfund Sites.
The purpose of the ROD is to fulfill statutory requirements pursuant to Sections 113(k)(2XB),
117(a), and 121(f)(I)(G) of CERCLA. It describes the alternatives analyzed, identifies the
preferred alternative, explains the rationale for preference, and serves as companion to the
Remedial Investigation (RI) Report, Feasibility Study (FS) Report, the Proposed Plan, and
Administrative Record File.
This ROD has been formulated by USEPA in conjunction with federal and state agencies
including: United States Department of the Interior (DOI), United States Fish & Wildlife Service
(USF&W), National Oceanic and Atmospheric Administration (NOAA), Agency for Toxic
Substance and Disease Registry (ATSDR), Louisiana Office of Public Health (LOPH), and the
Louisiana Department of Environmental Quality (LDEQ).
SITE NAME, LOCATION, AND DESCRIPTION
The Madisonville Creosote Works Superfund Site includes two major site components
comprised of the On-site and Off-site areas.
The property of the former MCW wood treating facility is referred to as the On-site area and
covers about 29 acres in Section 42, Township 7S, Range 10E, St. Tammany Parish, in
southeastern Louisiana. It is adjacent to the southern side of Louisiana State Highway 22
(SH22), about 3 miles west of downtown Madisonville and 1.25 miles from the Madisonville
city limits. The approximate geographical center of the Site is at 30°25'38" north latitude and
90°11'55" west longitude as measured from the United States Geological Survey (USGS)
7.5-minute series topographic quadrangle for Madisonville, Louisiana. The address of the
property is 1421 West Highway 22, Madisonville, Louisiana 70447.
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The first site component of the MCW Site is the On-site area. This On-site area consists of the
property occupied by the former wood treating facility when it was in operation. Descriptions of
the current On-site area conditions are as follows:
The predominant surface features are associated with the facility's operational areas
including a storage shed, a storage building with a lavatory, a small weigh station, a concrete
containment area, ditches, the former treated wood storage areas, the former process area, and.
former process water ponds and lagoons.
The On-site area has an established infrastructure including transportation routes and
accessible electric, gas, and telephone utilities. Water is available from an artesian industrial
well screened in the Lower Ponchatoula Aquifer. Road access to the On-site area is available
by SH22.
Many of the former process area features were removed during a USEPA Time Critical
Removal Action from September 23, 1996, to January 9, 1997. This action involved the
demolition, consolidation, and Off-site disposal of 11 On-site buildings and their contents,
the process area, piles of treated wood, and steel railroad tracks leading from treatment
cylinders to wood storage areas. In addition, a 6-foot high chain-link fence with barbed wire
was installed along the side of the On-site area adjacent to SH22. Previously installed
three-strand barbed wire fencing is intact along the property line on the other three sides of
the On-site area.
The second site component of the MCW Site is the Off-site area. The Off-site area surrounds the
On-site area and is predominantly rural and wooded. The Off-site areas include:
An unnamed drainage ditch alongside SH22 directly north of the On-site area.
An unnamed north stream flowing north from the On-site area, heading northeast through
undeveloped property, turning east-southeast through residential property, back across SH22
through a culvert, then south through undeveloped property until it merges with the south
stream to form a tributary of the Black River. A small unnamed pond is located east of the
confluence of the north and south streams.
An unnamed south stream flowing south from the On-site area, heading southeast through
undeveloped property, and curving southward after joining with the north stream and passing
by the small unnamed pond.
The City of Madisonville is the population center closest to the MCW Site. The Madisonville
incorporation boundary is 1.25 miles east-southeast of the site on SH22. As reported in the 1990
census, Madisonville had a population of 659. Estimated population distributions from the On-
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site area are as follows: approximately 33 persons reside within a 0.25-mile radius, 48 persons
within a 0.50-mile radius, and 312 persons within a 1.0-mile radius. The nearest residences are
located adjacent to the On-site area on SH22, on Koepp Road to the east, and on Trapagnier
Road to the west.
The St. Tammany Parish Police Jury established a land use ordinance in 1973 that regulates
development within unincorporated areas of the parish. Developments existing prior to 1973,
such as the property occupied by the former MCW wood treating facility, are not required to be
zoned by the St. Tammany Parish Land Use Ordinance.
The district surrounding the MCW Site is primarily zoned as rural, however, large tracts within 1
mile of the MCW Site were recently rezoned for suburban use. This rapid suburbanization of the
area surrounding the MCW Site is evidenced by recent housing developments within the Black
River Estates, Black River Forest, Claiborne Oaks, White Oaks Estates, and Pine Oak Estates
subdivisions. Therefore, a reasonably anticipated future land use for the MCW Site is residential
and/or recreational.
A map of the MCW Site can be found in Figure 1.
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FIGURE 1: MCW SITE MAP- See Region
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SITE HISTORY
The MCW Site consists of a former wood treating facility. Wood preserving operations at MCW
began in 1956 or 1957 under the name of Madisonville Creosote Works, Inc. During its
operation, the Site facility treated telephone poles, railroad ties, and lumber by impregnating the
wood with creosote in retort cylinders under elevated temperature and pressure. Creosote is a
complex mixture of organic compounds produced from the high temperature carbonization of
bituminous coal consisting of approximately 85% polynuclear aromatic hydrocarbons (PAHs),
10% phenolic compounds, and 5% nitrogen-, sulfur-, or oxygen-containing heterocycles. Some
compounds within the creosote mixture are carcinogenic. No other wood-treating chemicals have
been found to be used for the wood treating activities at the MCW facility.
In the treatment process, wood products were prepared for treatment by the supplier before
delivery to the facility. Upon arrival, the wood was placed on a tram and loaded into one of three
cylinders. The cylinder was heated by boiler-generated steam to remove excess moisture from
the wood and to expand the wood for creosote penetration. A vacuum was applied afterward,
and the condensed steam was pumped to the wastewater treatment system blowdown/separator
bulk. The wastewater was released from the cylinder to bring it to atmospheric pressure. Air and
creosote were then introduced to the cylinder at a pressure ranging from 150 to 200 pounds per
square inch to facilitate creosote penetration. The period of time required for pressure treatment
depended on the amount and size of the wood product being treated. After pressure treatment,
the remaining creosote was pumped back to the working tank through process and waste pipes.
A final vacuum was applied to remove excess creosote from the cylinder. Exhaust containing
steam and creosote vapors was routed to a heat-exchanger collection tank through the process
and waste pipes and then into the blowdown/separator.
The waste streams generated during the facility's operational years included process water,
cooling water, boiler blowdown water, and waste creosote. The process water and creosote
waste are considered hazardous wastes as defined by Resource Conservation and Recovery Act
(RCRA) regulations. These RCRA hazardous wastes are also hazardous substances as defined in
CERCLA. The cooling and boiler blowdown water were considered non-hazardous waste
streams under RCRA.
Since 1974, the facility used two process water ditches and two ponds to convey and store
process waste liquids and sludges. Waste creosote and wastewater drained from the treatment
cylinders to the large process ditch. The small process ditch conveyed waste liquids from the
large process ditch to a former process water pond. The solids then settled, and water
overflowed through a depression in the earthen dike into an evaporation pond. Two additional
ponds were available to contain overflow from the evaporation pond. All of the ditches and
ponds were unlined depressions about 5 feet deep and surrounded by small earthen dikes.
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In 1982, the MCW facility was purchased by Madisonville Wood Preserving Company, Inc.
(MWP). System modifications, process changes, and environmental permit applications were
initiated through its contractor, Ball Engineering, upon change of Site ownership to MWP. A
closed loop treatment system was installed as part of the system modifications in 1985. The
system was designed to recycle waste creosote and wastewater generated by the wood
preservation process. The treated water was placed in a cooling tower where the water
evaporated to the atmosphere. Creosote sludge in the pressure-treating cylinders was
periodically removed, placed in drums, and taken off site for disposal by a contractor. All four
ponds and the process water ditches were closed as solid waste management units by MWP
between 1984 and 1986 under an LDEQ approved and inspected closure. However, a
post-closure maintenance and monitoring plan was required due to the presence of ground water
contamination. The ground water monitoring plan was implemented by MWP through 1993.
In December 1986, MWP was issued a National Pollutant Discharge Elimination System
(NPDES) permit for two outfalls along the central ditch that merged with the southwest ditch and
led to the south stream. Uncontaminated cooling water from the compressor and steam
condensate from the boiler were discharged through the NPDES outfalls.
During 1988, the LDEQ Inactive and Abandoned Sites Division approved a privately financed
site remediation plan for the south stream. From October 31 to December 2, 1988, removal and
disposal of contaminated soil were conducted along a 950-foot portion of the south stream.
However, these activities were stopped abruptly due to the exhaustion of funds.
In December 1993, LDEQ issued three additional state discharge permits to MWP for untreated
storm water runoff from the northeastern area of the site to the SH22 ditch, untreated process
area stormwater runoff from the northwestern quadrant of the site to the SH22 ditch, and treated
sanitary wastewater from the mechanical package treatment plant to an unnamed ditch.
On March 30, 1994, the mortgage on the MWP property was liquidated in a property exchange
settlement between MWP and Citizens and Trust Company of Covington, Louisiana. MWP
ceased operations on July 5,1994, as a result of financial difficulties, and it formally declared
financial insolvency in May 1995.
On July 22,1994, LDEQ referred the MCW Site to USEPA. An USEPA Site Inspection was
conducted and on January 5, 1995, the Site was referred to USEPA Compliance Assurance and
Enforcement Division for evaluation of options available to address the contamination at the site.
All existing and former On-site structures can be found on Figure 2.
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FIGURE 2: FORMER ON-SITE STRUCTURES - See Region
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USEPA SUPERFUND HISTORY
On January 10,1996, the USEPA Compliance Assurance and Enforcement Division transferred
remedial action lead to the USEPA Superfund Division after unresolved negotiations with the
MCW facility.
On March 14,1996, residential water sampling was conducted around the immediate perimeter
of MCW. Private wells screened within the Shallow Aquifer (a domestic water supply source for
some residents in the area, located at a depth of approximately 80 to 200 feet below ground
surface) are sampled. No creosote constituents were found in the drinking water.
On March 26, 1996, USEPA initiated the RI to determine the nature and extent of the
contamination related to the MCW Site. Field activities and data collected between May 1996-
August 1997 are conducted to support the RI.
On June 17,1996, USEPA Region 6 proposed to USEPA Headquarters the inclusion of the
MCW Site on the NPL.
On July 23,1996, USEPA indicated in its Potentially Responsible Parties (PRPs) Report, that no
viable PRPs exists.
On September 10,1996, an open house was conducted to share information with the community
on activities relating to the MCW Site.
From September 23,1996, to January 9,1997, the USEPA mobilized the U.S. Corps of
Engineers to begin a Time Critical Removal of the process area on the MCW Site. A fence to
secure the On-site area was constructed and buildings associated with the former process area
were demolished. Removed waste associated with the former process area included: 371 tons of
creosote sludge, 1,512 gallons of creosote sludge, 8,000 gallons of creosote liquid, 78,602
gallons of contaminated water, 520 tons of contaminated concrete, 106 tons of contaminated
piping/metal, 300 tons of contaminated woodchips, 1 drum of mercury contaminated apparatus,
and 14 cubic yards of asbestos containing material.
On November 12,1996, an ecological evaluation report was completed by the USEPA
Environmental Response Team. The physical, chemical, and biological characteristics of the
stream system which drains the MCW Site were studied and assessed based on field activities
conducted in June and September 1996.
On December 23,1996, the USEPA announced the fmalization of the MCW Site to the NPL.
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On January 17, 1997, USEPA initiated work on the FS to evaluate the data collected for the RI
and cleanup solutions based upon review of all remedial alternatives.
On February 6,1997, an open house was conducted to share information with the community on
activities relating to the MCW Site.
On March 27,1997, the Human Health Risk Assessment and Ecological Screening Risk
Assessment was completed.
In August 1997, following community meetings and interviews with local residents and officials,
the Community Relations Plan was developed.
On September 26, 1997, the RI Report for all On-site areas was completed.
On October 24,1997, the RI Supplemental Sampling Report for all Off-site areas was completed.
On November 18,1997, the FS Report was completed for the MCW Site.
On March 3,1998, the Proposed Plan for cleanup at the MCW Site was presented to the
community at an open house meeting.
On March 26,1998, a public meeting was held to solicit any comments on the Proposed Plan. A
court reporter was present and all comments were documented.
In April 1998, the formal 30-day public comment period ended and USEPA begins the
evaluation of community comments and State input for the ROD.
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COMMUNITY PARTICIPATION
The community interest at the MCW Site has been high. USEPA held many informal meetings
and visited with community leaders and area residents on a regular basis. A Community
Relations Plan, completed in August 1997, was developed by USEPA with the help of the area
residents.
Three community open houses (September 10, 1996; February 7, 1997; March 3, 1998) and one
public meeting (March 26,1998), were held at the Madisonville City Hall. A community
Technical Assistance Grant was offered to the community beginning on February 7, 1997, but no
applications for the grant were received.
USEPA is presenting this ROD as part of its public participation responsibilities under Section
117(a) of CERCLA. The remedy for the MCW Site considers elements of remedies and cleanup
information previously presented to the community during public open houses and
recommendations from the public and various government support agencies.
Based on investigative data, technical reports and public involvement, USEPA presented a
Proposed Plan for cleanup to the public in March 1998 that meets the goals of USEPA in
addressing the human health and ecological threats presented at the Site. Public comments
concerning this Proposed Plan are addressed in the Responsiveness Summary section of the
USEPA ROD.
This ROD summarizes information that can be found in greater detail in several documents
found in the Administrative Record File for the MCW Site. USEPA encourages the community
to review these documents in order to better understand the MCW Site and the various Superfund
activities that have been conducted there. The Administrative Record File is available at the
following locations:
Madisonville Branch Library
Corner of Cedar and St. John Streets
P. O. Box 69
Madisonville, Louisiana 70447
(504) 845-4819
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Louisiana Department of Environmental Quality
Inactive and Abandoned Sites
7290 Blucbonnet
Baton Rouge, Louisiana 70809
(504) 865-0487
U.S. Environmental Protection Agency
12th Floor Library
1445 Ross Avenue
Dallas, Texas 75202-2733
(214) 665-6444
Information concerning USEPA, the Superfund process, and the MCW Site can also be accessed
via the Internet at:
USEPA Home Page: http://www.epa.gov
USEPA Region 6: http://www.epa.gov/earthlr6/index.htin
USEPA Region 6 Superfund Division: http://www.epa.gov/earth 1 r6/6sf/6sf.htm
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SCOPE AND ROLE OF RESPONSE ACTION
The overall Site cleanup strategy is to clean up the On-site and Off-site areas of contamination to
formulated risk standards such that the areas of concern is made safe for residential and
recreational usage. The three major parts of the response action includes: LTTD; DNAPL
Recovery Trench System; and, institutional controls/ground water monitoring.
The LTTD component of the cleanup remedy will address the principal threats wastes at the
MCW Site. Cleanup of creosote liquid source materials located in approximately 75,000 cubic
yards of contaminated soil and sediment removes this principal threat to human health and the
environment and satisfies the statutory preference for treatment of such substances.
The DNAPL Recovery Trench System will contain and recover the low-level threats at the MCW
Site. Containment and recovery of the low teachability creosote source materials within the
shallow clayey-silt saturated zone, approximately 15-25 feet below ground surface, will prevent
any migration of contaminants into the viable aquifers and reduce and/or eliminate the source
contaminants.
These components plus institutional controls ensure that future individuals will not be exposed to
the Site contaminants. Data from ground water monitoring will reflect the effectiveness of this
remedy over time.
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SUMMARY OF SITE CONTAMINATION
Site media that pose potentially unacceptable risks to human health and the environment
represent areas of potential contamination. At the MCW Site, the areas of potential
contamination were identified and include:
On-site and Off-site soil and sediment;
On-site and Off-site surface water; and,
On-site and Off-site ground water.
MCW Site specific geology and associated hydrogeology have been delineated by USEPA in
order to address these areas of potential contamination. In descending order from the ground
surface, the geological formations are described as the following:
1. Surface soils or fill materials from approximately ground surface to 2 feet below ground
surface (BGS);
2. Shallow clayey-silt from approximately just below surface soils to 25 feet BGS (the first
saturated zone is located within this matrix);
3. Intermediate clay/peat from approximately 25 to 30 feet BGS;
4. Intermediate silt from approximately 32 to 35 feet BGS (the second saturated zone is located
within this matrix); and,
5. Deep silty-clay from approximately 35 to 80 feet BGS (the third saturated zone, before the
Shallow Aquifer, is located within this matrix).
Information gathered during the RI geological and hydrogeological investigations revealed that
the three saturated zones did not constitute viable aquifers because of their low hydraulic
conductivity and slow recharge. Hence, the ground water at the MCW Site, composed of these
three saturated zones, is not viable for domestic or industrial purposes. The data collected from
these saturated zones is as follows:
Shallow clayey-silt: hydraulic conductivity 10"4 to 10"* cm/sec; flow velocity 0.0035 ft/day;
Intermediate silt: hydraulic conductivity 10"4 cm/sec; flow velocity 0.014 ft/day; and,
Deep silty-clay: hydraulic conductivity 10"6 to 10"8 cm/sec; flow velocity 0.0002 ft/day.
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Viable aquifers, not associated with the saturated zones at the MCW Site, for domestic and
industrial water usage were also identified during the RI and are listed as follows:
Shallow Aquifer, also known as the Upland Terrace Aquifer, from approximately 80 to 200
feet below ground surface;
Upper Ponchatoula Aquifer from approximately 250 to 650 below ground surface; and,
Lower Ponchatoula Aquifer from approximately 650 to 1100 feet below ground surface.
USEPA conducted numerous investigations during the RI into the identified areas of potential
contamination (On-site and Off-site soil, sediment, surface water, and ground water).
On-site soil contamination is defined by the layer of contaminated soil that is not more than 4
feet below ground surface (surface soil matrix of 2 feet below ground surface and the upper 2
feet of the next descending shallow clayey-silt matrix). Off-site soil contamination is further
delineated to no more than the banks of the north drainage ditch and the banks of the north and
south streams. The layer of soil contamination that is in contact with surface water defines
sediment contamination in the north drainage ditch, north stream, and south stream.
The estimated volume of contaminated On-site and Off-site soil and sediment is 75,000 cubic
yards. The majority of the soil contamination is located within On-site areas. A map of the
estimated extent of soil and sediment contamination at the MCW Site addressed in this ROD can
be found in Figures 3A and 3B.
Surface water contamination was also found at the MCW Site. Surface water contamination is
affected by the creosote contaminated soil and sediment sources. Once the contaminated soil and
sediments are removed from the streams and ditch, the source of surface water contamination
will be eliminated and no additional action will be required.
The ground water within the shallow clayey-silt matrix, immediately beneath the On-site area, is
contaminated. Creosote can be characterized as a DNAPL because it has a low solubility in
water and will separate out and settle towards the bottom within a saturated zone. DNAPL
contamination was found in this saturated zone, within the shallow clayey-silt matrix,
approximately 15 to 25 feet below ground surface. A map of the estimated DNAPL plume
underneath the MCW Site that needs to be addressed for containment is presented in Figure 3C.
25
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FIGURE 3 A: EXTENT OF ON-SITE AND NORTH OFF-SITE
CONTAMINATION - See Region
26
-------
FIGURE 3B: EXTENT OF SOUTH OFF-SITE CONTAMINATION
See Region
27
-------
FIGURE 3C: EXTENT OF DNAPL PLUME CONTAMINATION
See Region
28
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CURRENT AND POTENTIAL FUTURE SITE AND RESOURCES USES
The St. Tammany Parish Police Jury established a land use ordinance in 1973 that regulates
development within unincorporated areas of the parish. Developments existing prior to 1973,
such as the property occupied by the former MCW wood treating facility, are not required to be
zoned by the St. Tammany Parish Land Use Ordinance.
Currently the On-site area is not being used for business operations, residential, or recreational
purposes. The Off-site areas, especially the area southeast of the On-site area, are used for
hiking, hunting grounds for small game, and other recreational activities.
The district surrounding the MCW Site is primarily zoned as rural, however, large tracts within 1
mile of the MCW Site were recently rezoned for suburban use. This rapid suburbanization of the
area surrounding the MCW Site is evidenced by recent housing developments within the Black
River Estates, Black River Forest, Claiborne Oaks, White Oaks Estates, and Pine Oak Estates
subdivisions. Therefore, considering current development trends and community input, a
reasonably anticipated future land use for the MCW Site is residential and/or recreational.
29
-------
SITE RISKS
Data collected from the early stages of investigations by USEPA was used in the formulation of
Site risks in the form of risk scenarios. These risk scenarios are developed by USEPA for
reasonable maximum exposure (RME) in cases where they may be a potential pathway for
contamination to adversely affect human health and the environment. The RME estimate is
designed to measure a high-end rate of exposure instead of average exposure, as measured by the
Central Tendency Exposure (CTE) methodology. USEPA uses the RME methodology, in
comparison with CTE, to ensure that a conservative risk number is used when making decisions
concerning potential risks to human health and the environment.
The results of the risk scenario assessment are not exact estimates of the number of individuals
who will develop health problems. Rather, they are a statement of the relative magnitude of risk
if the assumed exposure occurs. Risk assessment is a tool which, when performed using the
standard algorithms and assumptions, provides risk managers with a way to quantitatively
compare sites and to set priorities in the interest of protecting human health and the environment.
EXPOSURE PATHWAY SCENARIOS
Five risk exposure pathway scenarios (EPS) were evaluated during the human health risk
assessment. The EPS were based on the risk assumption that the reasonably anticipated future
land use for the MCW Site will inevitably be residential and/or recreational because of the rapid
suburbanization that is developing around the Site. The five EPS are as follows:
EPS 1Trespassers potentially exposed to surface soil in On-site areas;
EPS 2Current and future residents exposed to surface soil and ground water in Off-site
residential areas along the banks of the drainage ditch along SH22;
EPS 3Recreational users exposed to sediment and surface water in Off-site areas;
EPS 4Future residents potentially exposed to On-site soil and ground water; and,
EPS 5Future residents potentially exposed to Off-site soil and ground water along the
banks of the north and south streams and along SH22.
The exposure conceptual model contains information on the formulation of these five EPS and
can be found on Chart 1.
30
-------
CHART 1: SITE EXPOSURE CONCEPTUAL MODEL
31
-------
CHART 1: SITE EXPOSURE CONCEPTUAL MODEL
PRIMARY
CONTAMINANT
SOURCES
PRIMARY
RELEASE
MECHANISM
SECONDARY
CONTAMINANT
SOURCES
SECONDARY
RELEASE
MECHANISM
PATHWAY
EXPOSURE
ROUTES
RECEPTORS
RME SCENARIO
Former Process Area
and Wood Storage/
Treatment Areas
(On-site)
1
Former Process Water
Impoundments (On-
site)
Discharge/Storm
water Runoff
-------
RISK CHARACTERIZATION
The risk characterization provides a bridge between the risk assessment and the risk management
decision-making process. The risk characterization combines information from the exposure
assessment and the toxicity assessment to characterization of the potential for carcinogenic and
non-carcinogenic health effects.
For carcinogenic health effects, the risk estimates for MCW Site creosote contamination are
additional or incremental risks that will be posed by potential exposure to contamination in the
On-site and Off-site areas if they are not addressed. That is, the risks are lifetime incremental
cancer risks, posed by the creosote contamination on the MCW Site, over and above the cancer
risk that each U.S. resident faces from other factors, such as genetic makeup, lifestyle and
chemicals we come in contact with everyday.
According to the National Oil and Hazardous Substances Pollution Contingency Plan (NCP),
which provides the framework for implementation of the USEPA Superfund program, this
lifetime incremental cancer risk should not exceed 1 excess cancer case in ten thousand
individuals (IxlO"4 or 1E-04) to 1 excess cancer case in one million individuals (1x10"*, 1E-06).
If indeed, through the calculation of the various EPS, there is shown an excess cancer risk above
the lifetime incremental cancer rate, then Remedial Action Objectives (RAOs) must be
developed to address them.
For non-carcinogenic health hazards, the Hazard Quotient (HQ) for a single substance and
Hazard Index (HI) for multiple substances and/or exposure pathways have been developed as a
measurement tool. Evaluation of non-carcinogenic risk is accomplished by dividing the
exposure intake of a chemical by the acceptable intake amount for that chemical. If this
evaluation results in a number higher than 1.0, as expressed by the HQ and HI, then a need for
remedial action may be warranted.
Of the five exposure scenarios, the future On-site residential scenario (EPS 4) resulted in the
highest total carcinogenic risk of 1 excess cancer case in ten individuals (1.1E-01). This risk
value exceeds the acceptable risk range as specified in the NCP and represents an unacceptable
risk. The future On-site residential scenario (EPS 4) also resulted in an unacceptable non-
carcinogenic risk (HI of 67 for the child and 36 for the adult). The majority of the upper bound
excess cancer risk and non-carcinogenic risk is attributable to PAHs. Both carcinogenic and non-
carcinogenic risks were driven by ingestion of ground water, which contributed more than 98
percent of the total risk. However, even if no ground water was used, ingestion of contaminated
soil would result in an unacceptable risk level of almost 4 excess cancer cases in ten thousand
individuals (3.9E-04).
32
-------
The future Off-site residential scenario (EPS 5) resulted in a total carcinogenic risk of 2.3E-02
and total His of 17 for the child resident and 5.7 for the adult resident. Both carcinogenic and
non-carcinogenic risk values represent unacceptable risk for this scenario. The risks for EPS 5
were driven by the ingestion of soil. PAHs were the most significant contributors to the
carcinogenic risk from ingestion of soil. Ingestion of ground water also posed significant
carcinogenic and non-carcinogenic risks. PAHs were the primary contributors to the risk from
ingestion of ground water.
The current and future Off-site residential scenario (EPS 2) resulted in a total carcinogenic risk of
1.9E-03 and total His of 13 for the child resident and 4.4 for the adult resident. Both
carcinogenic and non-carcinogenic risk values represent unacceptable risk for this scenario.
These risks were driven by the ingestion of soil. PAHs were the most significant contributors to
the carcinogenic risk. HeptachJor epoxide and PAHs were the most significant contributors to
the non-carcinogenic risks from ingestion of soil. Ingestion of ground water also posed
significant carcinogenic and non-carcinogenic risks. Arsenic was the primary contributor to
these risks.
The total carcinogenic risks for the On-site trespasser scenario (EPS 1) and the Off-site
recreational user scenario (EPS 3) were 1.7E-05 and 6.0E-05, respectively. The carcinogenic
risks for EPS 1 and EPS 3 were below the carcinogenic risk level of 1 .OE-04, and the His were
below 1.0. These carcinogenic and non-carcinogenic risk values are within acceptable limits
established by USEPA.
Based on the calculated health risks, remediation of the saturated zones may be necessary if the
ground water at the MCW Site is to be used for human ingestion and non-ingestion purposes in
the future. However, the hydrogeology investigation revealed that the ground water in the
saturated zones could not yield sufficient quantities of water to be a viable source for domestic
use; therefore, active remediation of the saturated zones is not warranted.
All reported domestic wells that are being used within a 1 mile radius of the MCW Site are
screened in the viable aquifers, that is, the Shallow Aquifer (80 to 200 feet BGS), Upper
Ponchatoula Aquifer (250 to 650 feet BGS), or the Lower Ponchatoula Aquifer (630 to 1100 feet
BGS). Containment would be necessary to ensure that the creosote contamination within the
saturated zones will not migrate to the viable aquifers.
If the MCW Site is to be used for residential or recreational purposes, the health risks posed to
current and potential future users by PAHs in the On-site and Off-site soils along the banks of the
north drainage ditch, north stream, and south stream indicate a need for remediation. Site risk
information containing the summary of COCs and the exposure routes exceeding a carcinogenic
risk of 1E-06 and non-carcinogenic risk of HI>1.0 can be found on Tables 1 and 2.
33
-------
Ecological risks associated with exposure to contaminants in soil, sediment, and surface water
were also evaluated for terrestrial and aquatic receptors inhabiting and potentially inhabiting the
MCW Site area. The evaluation of potential hazards to ecological receptors at the MCW Site
included comparisons of receptor species and exposure to creosote contamination in media,
forage, and prey items. Target receptor species, involving raccoon, mink, short tailed shrew,
white footed mouse, kingfisher, and red winged blackbird, were evaluated by modeling exposure
to creosote contamination through the ingestion of media and forage/prey (ingestion of soil,
surface water, sediment, vegetation, terrestrial and aquatic invertebrates, fish, and small
mammals). The results of this ecological screening assessment conclude that habitat quality
appears to have a greater effect on terrestrial and aquatic receptors than does MCW Site related
contamination.
34
-------
TABLE 1:
SUMMARY OF CHEMICALS AND EXPOSURE ROUTES EXCEEDING LIFETIME CANCER RISK OF 1E-06
Exposure Pathway
Scenario
EPS1
Trespassers potentially
exposed to surface soil in
On-site areas
EPS1
Trespassers potentially
exposed to surface soil in
On-site areas
EPS 2
Current/future resident
exposed to surface soil
and ground water in Off-
site residential areas
along the banks of the
drainage ditch along
SH22
Receptor
RME - 7-to- 16-year-old
trespasser
CTE- 7-to- 16-year-old
trespasser
RME - Adult resident
Chemicab Exceeding 1E-06 Carcinogenic Risk
(Total Risk through All Exposure Routes)
Chemical
Benzo(a)pyrene
Benzo(b)fluoranthene
Dibenzo(a,h)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(a)pyrene
Benzo(a)anthracene
Arsenic
Dibenzo(a,h)anthracene
Benzo(b)fluoranthene Heptachlor
epoxide
Carbazole
Indeno( 1 ,2,3-cd)pyrene
Aldrin
N-Nitroso-di-n-propylamine
Benzo(k)fluoranthene
Chrysene
Beryllium
Carcinogenic Risk
l.OE-05
4.0E-06
1.5E-06
5.IE-06
2.0E-06
7.6E-04
4.2E-04
2.6E-04
1.8E-04
1.1E-04
7.0E-05
4.7E-05
3.0E-05
1.5E-05
I.2E-05
1.2E-05
l.OE-05
3.4E-06
Exposure Routes Exceeding 1E-06 Carcinogenic
Risk (Total Risk from All Chemicals)
Exposure Route
Incidental ingestion of
soil
Incidental ingestion of
soil
Incidental ingestion of
soil
Ingestion of ground
water
Carcinogenic Risk
1.7E-05
8.6E-06
1.7E-03
2.2E-04
35
-------
TABLE 1 (Continued)
SUMMARY OF CHEMICALS AND EXPOSURE ROUTES EXCEEDING LIFETIME CANCER RISK OF 1E-06
Eiposure Pathway
Scenario
EPS 2
Current/future resident
exposed to surface soil
and ground water in Off-
site residential areas
along the banks of the
drainage ditch along
SH22
EPS 3
Current/future
recreational user exposed
to sediment and surface
water in Off-site areas
Receptor
CTE-5-to- 13-year-old
resident
RME-7-to- 16-year-old
recreational user
Cbemicab Exceeding 1E-06 Carcinogenic Risk
;_ (ToUl Risk through AU Exposure Routes)
' .. . "=?-' '' '-"''-:''- * '
Chemical
Benzo(a)pyrene
Benzo(a)anthracene
Arsenic
Dibenzo(a,h)anthracene
Benzo(b)fluoranthene Heptachlor
epoxide
Carbazole
Indeno( 1 ,2,3-cd)pyrene
Aldrin
N-Nitroso-di-n-propylamine
Benzo(k)fluoranthene
Chrysene
Beryllium
Benzo(a)pyrene
Benzo(a)anthracene
Benzo(b)fluoranthene
Arsenic Dibenzo(a,h)anthracene
Carcinogenic Risk
2.5E-04
1.4E-04
6.1E-05
5.8E-05
3.7E-05
2.2E-05
1.5E-05
9.6E-06
4.9E-06
3.9E-06
3.8E-06
3.2E-06
1.1E-06
4.1E-05
l.OE-05
4.2E-06
2.0E-06
1.1E-06
Exposure Routes Exceeding 1E-06 Carcinogenic
Risk (Total Risk from All Chemicals)
,- -. ,; 'V ;::_:
Exposure Route
Incidental ingestion of
soil
Ingestion of ground
water
Incidental ingestion of
sediment
Carcinogenic Risk
5.5E-04
4.7E-05
6.1E-05
36
-------
TABLE 1 (Continued)
SUMMARY OF CHEMICALS AND EXPOSURE ROUTES EXCEEDING LIFETIME CANCER RISK OF 1E-06
Exposure Pathway
Scenario
EPS 3
Current/future
recreational user exposed
to sediment and surface
water in Off-site areas
EPS 4
Future residents
potentially exposed to
On-site soil and ground
water
Receptor
CTE - 7-to- 16-year-old
recreational user
RME - Adult resident
Chemicals Exceeding 1E-06 Carcinogenic Risk
. , (Total Risk through All Exposure Routes)
' Chemical !£ ; ...
Benzo(a)pyrene
Benzo(a)anthracene
Benzo(b)fluoranthene
Arsenic
Benzo(a)pyrene
Benzo(a)anthracene
Benzo(b)fluoranthene
Dibenzo(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Benzo(k)fluoranthene
Carbazole
Benzene
Chrysene
Chloroform
Arsenic
Heptachlor epoxide
Beryllium
Carcloogenk Risk
2.1E-05
5.1E-06
2.1E-06
l.OE-06
6.3E-02
1.8E-02
1.4E-02
8.7E-03
2.7E-03
1.5E-03
3.8E-04
2.9E-04
1 .7E-04
3.7E-05
9.5E-06
2.7E-06
1.2E-06
Exposure Routes Exceeding 1E-06 Carcinogenic
Risk (Total Risk from All Chemicals)
i
Exposure Route
Incidental ingestion of
sediment
Incidental ingestion of
soil
Ingestion of ground
water
Inhalation of volatiles
while showering
Carcinogenic Risk
3.0E-05
3.9E-04
1.1E-01
2.6E-04
37
-------
TABLE 1 (Continued)
SUMMARY OF CHEMICALS AND EXPOSURE ROUTES EXCEEDING LIFETIME CANCER RISK OF 1E-06
Eiposure Pathway
Scenario
EPS 4
Future residents
potentially exposed to
On-site soil and ground
water
Receptor
CTE - 5-to- 13-year-old
resident
Chemicals Exceeding 1E-06 Carcinogenic Risk
(Total Risk through All Exposure Routes)
Chemical
Benzo(a)pyrene
Benzo(a)anthracene
Benzo(b)fluoranthene
Dibenzo(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Benzo(k)fluoranthene
Carbazole
Benzene
Chrysene
Chloroform
Arsenic
Carciaofenk Risk
1.4E-02
3.9E-03
2.9E-03
1.9E-03
5.9E-04
3.3E-04
8.1E-05
8.1E-05
3.8E-05
1.IE-05
3.1E-06
Exposure Routes Exceeding 1E-06 Carcinogenic
Risk (Total Risk from All Chemicals)
Exposure Route
Incidental ingestion of
soil
Ingestion of ground
water
Inhalation of volatiles
while showering
Carcinogenic Risk
1.3E-04
2.4E-02
7.8E-05
38
-------
TABLE 1 (Continued)
SUMMARY OF CHEMICALS AND EXPOSURE ROUTES EXCEEDING LIFETIME CANCER RISK OF 1E-06
Exposure Pathway
Scenario
Receptor
Chemicals Exceeding 1E-06 Carcinogenk Risk
(Total Risk through All Exposure Routes)
Chemical
Carcinogenic Risk
Exposure Routes Exceeding 1E-06 Carcinogenic
Risk (Total Risk from All Chemicals)
Exposure Route
Carcinogenic Risk
Future residents
potentially exposed to
Off-site soil and Off-site
ground water
RME - Adult resident
Benzo(a)pyrene
Benzo(a)anthracene
Benzo(b)fiuoranthene
Dibenzo(a,h)anthracene
Benzo(k)fluoranthene
Indeno( 1,2,3-cd)pyrene
Heptachlor epoxide
Carbazole
Chrysene
Arsenic
Benzene
N-Nitroso-di-n-propylamine
Aldrin
Beryllium
Chloroform
1.3E-02
5.5E-03
3.1E-03
6.4E-04
2.8E-04
1.8E-04
7.0E-05
6.6E-05
5.7E-05
3.0E-05
1.4E-05
1.2E-05
5.7E-06
3.1E-06
1.8E-06
Incidental ingestion of
soil
Ingestion of ground
water
Inhalation of volatiles
while showering
1.7E-02
5.5E-03
1.3E-05
39
-------
TABLE 1 (Continued)
SUMMARY OF CHEMICALS AND EXPOSURE ROUTES EXCEEDING LIFETIME CANCER RISK OF 1E-06
Exposure Pathway
Scenario
Receptor
Chemicals Exceeding 1E-06 Carcinogenic Risk
(Total Risk through All Exposure Routes)
Chemkal
Carcinogenic Risk
Exposure Routes Exceeding 1E-06 Carcinogenic
Risk (Total Risk from All Chemicals)
Exposure Route
Carcinogenic Risk
EPSS
Future residents
potentially exposed to
Off-site soil and Off-site
ground water
CTE - 5-to-13-year-old
resident
Benzo(a)pyrene
Benzo(a)anthracene
Benzo(b)fluoranthene
Dibenzo(a,h)anthracene
lndeno(l ,2,3-cd)pyrene
Benzo(k)fluoranthene
Heptachlor epoxide
Carbazole
Chrysene
Arsenic
Benzene
N-Nitroso-di-n-propylamine
Aldrin
Beryllium
3.7 E-03
1.7E-03
9.2 E-04
I.6E-04
4.4 E-05
8.0 E-05
2.2 E-05
1.9 E-05
1.7 E-05
9.6 E-06
4.1 E-06
3.9 E-06
1.8 E-06
1.0 E-06
Incidental ingestion of
soil
Ingestion of ground
water
Inhalation of volatiles
while showering
5.5 E-03
1.2E-03
3.9E-06
40
-------
TABLE 2:
SUMMARY OF CHEMICALS AND EXPOSURE ROUTES EXCEEDING HAZARD INDEX OF 1.0
Exposure Pathway
Scenario
EPS1
Trespassers potentially
exposed to surface soil in
On-site areas
EPS1
Trespassers potentially
exposed to surface soil in
On-site areas
EPS 2
Current/future residents
exposed to surface soil
and ground water in Off-
site residential areas along
the banks of the drainage
ditch along SH22
EPS 2
Current/future residents
exposed to surface soil
and ground water in Off-
site residential areas along
the banks of the drainage
ditch along SH22
Receptor
RME-7-to- 16-year-old
trespasser
CTE-7-to- 16-year-old
trespasser
RME - Child resident
RME - Adult resident
Chemicals Exceeding Hazard Index of 1 (Total
Hazard Index Through AU Exposure Routes)
Chemical
NA
NA
Heptachlor epoxide
Arsenic
Pyrene
Heptachlor epoxide
Arsenic
Hazard Risk
NA
NA
4.8
2.9
1.1
1.4
1.4
Exposure Routes Exceeding Hazard Index of 1 (Total
Hazard Index From All Chemicals)
Exposure Route
NA
NA
Incidental ingestion of
soil
Ingestion of ground water
Incidental ingestion of
soil
Ingestion of ground water
Hazard Risk
NA
NA
9.4
3.1
2.7
1.7
41
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TABLE 2 (Continued)
SUMMARY OF CHEMICALS AND EXPOSURE ROUTES EXCEEDING HAZARD INDEX OF 1.0
Exposure Pathway
Scenario
EPS 3
Current/future recreational
user exposed to sediment
and surface water in Off-
site areas
EPS 3
Current/future recreational
user exposed to sediment
and surface water in Off-
site areas
fpc »
iLIfcJ J
Current/future recreational
user exposed to sediment
and surface water in Off-
site areas
Receptor
CTE-5-to- 13-year-old
resident
RME - 7-to- 16-year-old
recreational user
CTE- 7-to- 16-year-old
recreational user
Chemicals Exceeding Hazard Index of 1 (Total
Hazard Index Through All Exposure Routes)
Chemical
Heptachlor epoxide
Arsenic
NA
NA
Hazard Risk
1.5
1.1
NA
NA
Exposure Routes Exceeding Hazard Index of 1 (Total
Hazard Index From All Chemicals)
Exposure Route
Incidental ingestion of
soil
Ingestion of ground water
NA
NA
Hazard Risk
2.9
1.2
NA
NA
42
-------
TABLE 2 (Continued)
SUMMARY OF CHEMICALS AND EXPOSURE ROUTES EXCEEDING HAZARD INDEX OF 1.0
Exposure Pathway
Scenario
EPS 4
Future residents
potentially exposed to On-
site soil and ground water
T
EPS 4
Future residents
potentially exposed to On-
site soil and ground water
Receptor
RME - Child resident
RME - Adult resident
Chemicab Exceeding Hazard Index of 1 (Total
Hazard Index Through All Exposure Routes)
".-.--- .:--v*hVi>'-:-..-i-. :. - ''-
Chemical ":
Fluoranthene
Pyrene
Fluorene
Acenaphthene
Zinc
4-Chloroaniline
4-Methylphenol
2,4-Dimethylphenol
Fluoranthene
Pyrene
Fluorene
Acenaphthene
Zinc
4-Chloroaniline
4-Methylphenol
2,4-Dimethylphenol
Hazard Risk
13.0
11.0
10.0
8.7
8.6
5.4
4.4
2.6
7.1
5.8
5.6
4.7
4.7
3.0
2.4
1.4
Exposure Routes Exceeding Hazard Index of 1 (Total
Hazard Index From All Chemicab)
Exposure Route
Ingestion of ground water
Ingestion of ground water
Hazard Risk
67.0
36.0
43
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TABLE 2 (Continued)
SUMMARY OF CHEMICALS AND EXPOSURE ROUTES EXCEEDING HAZARD INDEX OF 1.0
Exposure Pathway
Scenario
EPS 4
Future residents
potentially exposed to On-
site soil and ground water
EPSS
Future Exposure to
Off-Site Soil and On-Site
Ground water
EPSS
Future Exposure to
Off-Site Soil and Ground
water
Receptor
CTE-5-to- 13-year-old
resident
RME - Child resident
RME - Adult resident
Chemicals Exceeding Hazard Index of 1 (Total
Hazard Index Through All Ezpocure Routes)
Chemical
Fluoranthene
Pyrene
Fluorene
Acenaphthene
Zinc
4-Chloroaniline
4-Methylphenol
2,4-Oimethylphenol
Heptachlor epoxide
Pyrene
Fluoranthene
Fluorene
Acenaphthene
Heptachlor epoxide
Pyrene
Fluoranthene
Hazard Risk
5.1
4.1
4.0
3.4
3.4
2.1
1.7
1.0
4.8
3.3
3.1
1.8
1.3
1.4
l.l
1.1
Exposure Routes Exceeding Hazard Index of 1 (Total
Hazard Index From All Chemicals)
Exposure Route
Ingestion of ground water
Incidental ingestion of
soil
Ingestion of ground water
Incidental ingestion of
soil
Ingestion of ground water
Hazard Risk
26.0
14.0
3.3
3.9
1.8
44
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TABLE 2 (Continued)
SUMMARY OF CHEMICALS AND EXPOSURE ROUTES EXCEEDING HAZARD INDEX OF 1.0
Exposure Pathway
Scenario
Receptor
Chemicals Exceeding Hazard Index of 1 (Total
Hazard Index Through All Exposure Routes)
Chemical
Hazard Risk
Exposure Routes Exceeding Hazard Index of 1 (Total
Hazard Index From All Chemicals)
Exposure Route
Hazard Risk
EPSS
Future Exposure to
Off-Site Soil and Ground
water
CTE - 5-to-13-year-old
resident
Heptachlor epoxide
Fluoranthene
Pyrene
1.5
1.0
1.0
Incidental ingestion of
soil
Ingestion of ground water
4.2
1.3
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FORMULATION OF CLEANUP ACTION LEVELS
Based on the results of the human health risk assessment, carcinogenic risks posed the greatest
threat to current and future residents and recreational users. Carcinogenic risk was driven by the
presence of creosote PAHs, including benzo(a)pyrene (BAP).
The USEPA used BAP equivalent concentrations in the formulation of the cleanup action levels
for the MCW Site. Total BAP equivalent concentrations provide a means of evaluating total
PAHs as if the creosote PAHs were composed solely of BAP, the most toxic of the PAH
compounds. Thus, a cleanup action level for several PAH compounds can be expressed as a
specific level of a BAP equivalent.
BAP equivalent concentrations were related to the carcinogenic risks by the following methods:
In order to estimate the BAP equivalent concentrations needed for the cleanup action to match
the USEPA acceptable upperbound lifetime cancer risk (ULCR) levels of 1E-04, IE-OS, and 1E-
06, the estimated daily intake (EDI) of BAP was calculated for each ULCR.
The EDIs were calculated as follows:
ULCR
where,
££>/= estimated daily intake (milligrams per kilograms per day [mg/kg/day])
ULCR = upperbound lifetime cancer risk of 1E-04, IE-OS, and 1E-06 (unitless)
CSF= cancer slope factor of 7.3 (mg/kg/day)'1 for BAP
Once the EDIs were calculated, the BAP equivalent concentrations in soil corresponding to each
ULCR were calculated. The equations used to calculate the soil concentrations for each EPS are
as follows:
EPS 1 , trespassers potentially exposed to BAP from ingestion of surface soil in On-site areas,
was calculated as follows:
EDIxBWxAT
~ IRxCFxEFxED
where,
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CS = concentration of BAP in soil (mg/kg)
EDI- estimated daily intake (mg/kg/day)
BW = body weight (43 kg for trespasser)
AT'- averaging time (70 years x 365 days per year for cancer)
IR = ingestion rate (100 mg/day for trespasser)
CF- conversion factor (1E-6 kg/mg)
EF= exposure frequency (60 days year for trespasser)
ED = exposure duration (10 years for trespasser)
The soil concentrations for BAP based on ULCRs of 1E-04, IE-OS, and 1E-06 are 251,25.1, and
2.51 mg/kg, respectively.
EPS 2, EPS 4, and EPS 5, exposure to current and future On-site and Off-site residents from
incidental ingestion of surface soil, were calculated as follows:
EDhAT
Co =
CFxEFxIF
where,
CS = concentration of BAP in soil (mg/kg)
EDI = estimated daily intake (mg/kg/day)
AT- averaging time (70 years x 365 days/year for cancer)
CF- conversion factor (1E-6 kg/mg)
EF= exposure frequency (350 days/year for current and future residents)
IF= age adjusted soil ingestion factor (1 14 mg-year/kg-day)
IF was calculated as follows:
. ,-, _ (IRsoil/adi X EDggtl^) (IRmil/agtl-JlX EDqger.3l)
where,
7F= Age adjusted soil ingestion factor
BWage w = average body weight from age 1-6 (15 kg)
BWige7.3, = average body weight from age 7-31 (70 kg)
ED»gei-6 = exposure duration during ages 1-6 (6 yr)
EDage7.3, = exposure duration during ages 7-31 (24 yr)
IR xMiy. w = ingestion rate of soil age 1-6 (200 mg/day)
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IR soii/agt 7.31 = ingestion rate of soil age 7-31 (100 mg/day)
The soil concentrations for benzo(a)pyrene for EPS 2, EPS 4, and EPS 5 based on ULCRs of 1E-
4, 1E-5, and 1E-6 are 8.77, 0.88, and 0.08, respectively.
EPS 3, recreational user exposed to sediment in Off-site areas from ingestion, was calculated as
follows:
EDIxBWxAT
IRxCFxEFxED
where,
CS = concentration of benzo(a)pyrene in sediment (mg/kg)
££>/= estimated daily intake (mg/kg/day)
BW = body weight (43 kg for recreational user)
AT= averaging time (70 years x 365 days/year for cancer)
IR = ingestion rate (100 mg/day for recreational user)
CF= conversion factor (1E-6 kg/mg)
EF = exposure frequency (60 days/year for recreational user)
ED = exposure duration (10 years for recreational user)
The sediment concentration for BAP based on ULCRs of 1E-04, IE-OS, and 1E-06 are 251,25.1,
and 2.51 mg/kg, respectively.
Table 3 summarizes the required and the selected BAP equivalent concentrations (to one
significant digit) needed to determine completeness of the cleanup action, corresponding to each
EPS within the USEPA safe risk range of l.OE-04 to l.OE-06.
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TABLE 3:
CALCULATED BENZO(A)PYRENE CLEANUP ACTION LEVEL
CONCENTRATIONS
»>>v«5'''-.''.,vv:XV:V-. '';.". -A:"'. .'-Yrv .'.'.;.".> ' . ' "'-.. -.-
,., .^_ JOSltl^
?iBP^*v-
EPS I- Trespassers potentially exposed to surface soil in On-site
areas.
300
100
EPS 2- Current and future residents exposed to surface soil and
ground water in Off-site residential areas along the banks of the
drainage ditch along SH22 (north drainage ditch).
0.09
EPS 3- Recreational users exposed to sediment and surface water in
Off-site areas (north stream, north drainage ditch, south stream).
300
100
EPS 4- Future residents potentially exposed to On-site soil and
ground water.
0.09
EPS 5- Future residents potentially exposed to Off-site soil and
ground water along the banks of the north and south streams.
0.09
The USEPA determined that a cleanup action level of 3 mg/kg of BAP equivalents will be
required for all areas where EPS 2, EPS 4, and EPS 5 will be applicable; and, 100 mg/kg of BAP
equivalents for all areas where EPS 1 and EPS 3 will be applicable.
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REMEDIATION OBJECTIVES
The evaluation of the risk scenarios, involving human health and the environment, has revealed
results that exceed both the acceptable lifetime incremental cancer risk and acceptable non-
carcinogenic risks at the MCW Site. These results were used in the identification of principal
threats posed by the MCW Site.
Principal threats at this Site are the creosote PAHs that are considered highly toxic and present a
significant risk to human health or the environment should an exposure occur. These creosote
contaminants are considered principal threats when their calculated risk value indicate that
exposure to them will result in an individual's lifetime incremental cancer risk exceeding one
excess cancer case in ten thousand individuals (IxlO"4). The majority of the principal threats are
located within the On-site soil areas.
Following this identification of principal threats, the USEPA engaged in the formulation of
RAOs to address them. The RAOs are used to determine cleanup requirements for the MCW
Site in order to address the principal threats and reduce carcinogenic and non-carcinogenic risks
to generally accepted levels.
The RAOs for the MCW Site are as follows:
1) ON-SITE AREAS
SOIL: Prevent direct contact/ingestion with media exceeding the lifetime incremental
cancer risk of IxlO"4 to IxlO"6 due to carcinogenic PAHs based on residential risk
scenarios.
SEDIMENT: Prevent direct contact/ingestion with media exceeding the lifetime
incremental cancer risk of IxlO"4 to IxlO"6 due to carcinogenic PAHs based on
recreational risk scenarios.
SURFACE WATER: Prevent direct contact/ingestion with media exceeding the lifetime
incremental cancer risk of IxlO"4 to IxlO"6 due to carcinogenic PAHs based on
recreational risk scenarios.
GROUND WATER: Prevent migration of media contaminants into Shallow Aquifer
which would result in the Shallow Aquifer exceeding the Maximum Contaminant Levels
(highest permissible concentration of a substance allowed in drinking water) or lifetime
incremental cancer risk of IxlO"4 to IxlO"6 due to carcinogenic PAHs based on residential
risk scenarios.
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2) OFF-SITE AREAS
« SOIL: Prevent direct contact/ingestion with media exceeding the lifetime incremental
cancer risk of 1x10"4 to IxlO"6 due to carcinogenic PAHs based on residential (north
stream, north drainage ditch) and recreational (south stream) risk scenarios.
« SEDIMENT: Prevent direct contact/ingestion with media exceeding the lifetime
incremental cancer risk of 1x10"4 to 1x10"6 due to carcinogenic PAHs based on
recreational risk scenarios.
« SURFACE WATER: Prevent direct contact/ingestion with media exceeding the lifetime
incremental cancer risk of IxlO"4 to IxlO"6 due to carcinogenic PAHs based on
recreational risk scenarios.
« GROUND WATER: Prevent migration of media contaminants into Shallow Aquifer
which would result in the Shallow Aquifer exceeding the Maximum Contaminant Levels
(highest permissible concentration of a substance allowed in drinking water) or lifetime
incremental cancer risk of IxlO"4 to IxlO"6 due to carcinogenic PAHs based on residential
risk scenarios.
After calculation of the cleanup action levels needed to meet USEPA acceptable health based
risk standards, the following BAP equivalents performance goals are set and must be met in
order to achieve cleanup of the MCW Site:
I. BAP equivalent concentrations of 3.0 rag/kg for all RAOs where residential risk
scenarios are applicable; and,
II. BAP equivalent concentrations of 100.0 mg/kg for all RAOs where recreational risk
scenarios are applicable.
For all contaminated areas of the MCW Site (On-site and Off-site), these USEPA performance
goals translate into:
1) On-site:
« applicable risk scenarios: EPS 1, EPS 4.
* 3 mg/kg BAP equivalent concentrations for 0-2 ft BGS soils.
100 mg/kg BAP equivalent concentrations for 2-4 ft BGS soils.
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2) Off-site:
a) North Stream:
applicable risk scenarios: EPS 1, EPS 3, EPS 5.
affected length: northern On-site point of origin to Black River Ranch access road.
sediment removal (loose gravel/stream bed).
3 mg/kg BAP equivalent concentrations for 0-2 ft BGS bank soils.
100 mg/kg BAP equivalent concentrations for 2-4 ft BGS bank soil.
b) North Ditch:
applicable risk scenarios: EPS 1, EPS 2, EPS 3.
affected length: northwestern On-site area to Camps northeastern property boundary.
sediment removal (loose gravel/ditch bed).
3 mg/kg BAP equivalent concentrations for 0-2 ft BGS bank soils.
100 mg/kg BAP equivalent concentrations for 2-4 ft BGS bank soils.
c) South Stream
applicable risk scenarios: EPS 1, EPS 3
affected length: southern On-site point of origin to south stream/substation drainage
ditch junction.
sediment removal (loose gravel/stream bed).
100 mg/kg BAP equivalent concentrations for 0-1 ft BGS bank soils. Modification to
cleanup levels of the south stream bank soils will be implemented if limits of the
contamination are discovered to extend from this heavily wooded, marshy 'wetland'
area into areas where residential risk based cleanup levels, instead of recreational risk
based cleanup levels, are more applicable.
These targeted cleanup action levels place the risk protection level, from lifetime incremental
cancer risk due to carcinogenic chemical contaminants, midway between the 1E-04 to IE-OS
ranges. This midpoint value was chosen instead of the risk point of departure value (1E-06) due
to the existing scientific ability to analyze the media matrix, such as soil detection limits, and the
ubiquitous presence of PAHs. This level is also consistent with levels selected by USEPA in
RODs for other sites.
The targeted cleanup action levels, expressed by BAP equivalents performance goals, were
chosen based on protection of human health from carcinogenic risks within reasonably
anticipated future land use. When this protection is accomplished, through achieving the RAOs
for the various MCW Site contaminated areas, non-carcinogenic risks and ecological risks would
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also be reduced to safer levels. Confirmation sampling will be taken at the end of the cleanup
action to ensure the RAOs were met and targeted cleanup action levels were reached.
Also of note, the recreational user risk scenario was chosen for the Off-site area that consisted of
the south stream because of the presence of marshy, wetlands in this area. The USEPA reasoned
that this marshy Off-site area, where the south stream runs through before it joins the Black
River, would be more likely to be suitable for hunting, stream playing, and other recreational
activities, and therefore, based its RAO on this assumption.
As stated in the previous section (SUMMARY OF SITE CONTAMINATION), the estimated
combined On-site and Off-site volume of soil and sediment needed to be addressed to achieve
the RAOs established by the USEPA is estimated at 75,000 cubic yards. Since the majority of
the contamination is located within the On-site area, USEPA anticipates very limited cleanup
actions to be taken in the Off-site areas.
USEPA also concluded that DNAPL in the saturated zones would not be addressed for treatment,
but rather containment, in order to aid in achieving the MCW Site RAOs. The DNAPL,
consisting of low teachability creosote source contaminants within the shallow clayey-silt
saturated zone, has been identified as a low-level threat, and would be contained and recovered
by the DNAPL Recovery Trench System. This system, explained further in the ROD, will be
implemented to prevent any migration of contaminants into viable aquifers and reduce and/or
eliminate the source contaminants.
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DESCRIPTION OF REMEDIAL ALTERNATIVES
Fifteen potential remediation technologies and institutional controls were evaluated to address
the identified principal threats and to achieve the RAOs at the MCW Site. Of these, two
treatment technologies (LTTD and incineration), two containment technologies
(solidification/stabilization and capping), one extraction technology (DNAPL Recovery Trench
System), and one disposal technology (landfill disposal) were retained for detailed analysis.
These technologies were retained on the basis of their proven effectiveness, technical
implementability, and cost. Institutional controls also were retained for detailed analysis.
The retained technologies were carefully analyzed and shaped into the formulation of remedial
alternatives. These alternatives were formulated so that the resulting On-site areas will be useful
for residential purposes and Off-site areas for recreational purposes. As well, the range includes
alternatives that, to the maximum extent feasible, minimize the need for long-term management.
Alternatives were also developed to address the RAOs within an expedited time frame. The no
action alternative has been retained as a baseline for comparison, as required by the NCP. The
remedial action alternatives for the MCW Site are as follows:
Alternative 1No Further Action (required by NCP);
Alternative 2Institutional Controls / Ground Water Monitoring;
Alternative 3Low Temperature Thermal Desorption & DNAPL Recovery Trench System;
Alternative 4Incineration & DNAPL Recovery Trench System;
Alternative 5Solidification / Stabilization & DNAPL Recovery Trench System;
Alternative 6Capping & DNAPL Recovery Trench System; and,
Alternative 7Landfill Disposal & DNAPL Recovery Trench System
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ALTERNATIVE 1: NO FURTHER ACTION
USEPA is required to consider the No Further Action alternative in accordance with the NCP (40
CFR 300.430 [e][6]). The no further action alternative is the baseline alternative against which
the effectiveness of all other remedial alternatives are judged. Under the no further action
alternative, no remedial actions will be conducted at the MCW On-site or Off-site areas. No
further attempts will be made beyond those already implemented (such as the USEPA Time
Critical Removal as detailed under the sections: SITE HISTORY and USEPA SUPERFUND
HISTORY) to control access to the contaminated areas of the MCW Site. Uncontrolled surface
water runoff will continue to be released from both natural and constructed drainage pathways.
DNAPL found within the saturated zones underneath the MCW Site will continue to be a source
for ground water contamination. Also, no attempts will be made to monitor or control ground
water contamination and DNAPL migration to usable drinking water aquifers.
ALTERNATIVE 2: INSTITUTIONAL CONTROLS / GROUND WATER MONITORING
Alternative 2 will involve the implementation of institutional controls. Institutional controls,
which are legal and administrative measures that prevent exposure to contaminants at
concentrations above health based risk levels that may remain at the MCW Site such as deed
notices and/or deed restrictions, will be used to eliminate or minimize the potential for direct
exposure to contaminants.
Deed notices on the MCW Site will offer a long-term remedy deterring future development and
use of the property that might lead to direct exposure to creosote contamination present in soils,
sediments, surface water, and ground water. Deed notices are intended to provide notice to
current and future owners that contamination remains and that the extraction and use of the
contaminated ground water in the saturated zones should be avoided.
In addition to institutional controls, security fencing and warning signs will be installed. The
erection of a security fence will inhibit the ingress and egress of the casual trespasser and the
warning signs will caution trespassers of potential dangers and explain the consequences for
persons caught trespassing. The fence and signs will be inspected periodically for damage or
wear and can be repaired easily.
Alternative 2 will include ground water monitoring. This will include collection of samples from
Site monitoring wells and nearby residential water supply wells. Samples will be analyzed for
VOCs, PAHs, total petroleum hydrocarbons, and target analyte list metals. Monitoring
frequency will be determined based on sampling results and the demonstration of the
effectiveness of the remedy over time.
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ALTERNATIVE 3: LOW TEMPERATURE THERMAL DESORPTION & DNAPL
RECOVERY TRENCH SYSTEM
Alternative 3 is the excavation and treatment of contaminated soil and sediments using LTTD
technology. LTTD technologies are usually operated at slightly lower temperatures (300 to
1,200 °F) than traditional incineration technologies.
On-site and Off-site soil will be stockpiled prior to treatment. Off-site excavations will be
backfilled with imported clean fill material. Contaminated soil will be fed into the processing
equipment based upon the soil type, soil moisture, contaminant level, and treatment goals. The
thermal desorption unit heats the soil in a rotary kiln to a temperature greater than the boiling
point of the creosote contaminants. As the soil is heated, the contaminants vaporize and enter the
gas stream and exits the thermal desorption unit.
The treated soil is then reconstituted with water in a pug mill and stockpiled. Periodically,
confirmatory samples will be collected to assess the efficacy of the treatment. Soil requiring
further treatment will be recycled through the process.
Before the treated soil is backfilled into the excavations, a DNAPL Recovery Trench System will
be installed. Following installation of the recovery trench system, the excavations will be
backfilled with the treated soil. A layer of topsoil will be placed over the treated soil, and the
area will be seeded.
Institutional controls will be implemented to ensure that future individuals will not be exposed to
the Site contaminants. Ground water monitoring will also be implemented and data from
sampling activities will reflect the effectiveness of this remedy over time.
ALTERNATIVE 4: INCINERATION & DNAPL RECOVERY TRENCH SYSTEM
Alternative 4 is the excavation and treatment of contaminated soil using a rotary kiln incinerator.
On-site and Off-site soil will be stockpiled prior to treatment. Contaminated soil will be fed into
the processing equipment based upon the soil type, soil moisture, contaminant level, and
treatment goals As the soil is heated, the contaminants vaporize and enter an afterburner. The
gases entering the afterburner are routed, under a negative pressure, to a secondary combustion
chamber. The gases exiting the secondary combustion chamber are then routed through a
cyclone turbine unit to remove any suspended air particulates. Next, the gas stream exiting the
cyclone turbine unit proceeds to the gas-cleaning system and then to the atmosphere through the
air stack. As particulates fall out of the gas-cleaning stream (after exiting the secondary
56
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treatment unit), either in the cyclone turbine unit or the gas-cleaning system, they are moved to
and then mixed with the treated soil.
The treated soil is then reconstituted with water in a pug mill and stockpiled. Periodically,
confirmatory samples will be collected to assess the efficacy of the treatment. Soil requiring
further treatment will be recycled through the process.
Before the treated soil is backfilled into the excavations, a DNAPL Recovery Trench System will
be installed. Following installation of the recovery trench system, the excavations will be
backfilled with the treated soil. A layer of topsoil will be placed over the treated soil, and the
area will be seeded.
Institutional controls will be implemented to ensure that future individuals will not be exposed to
the Site contaminants. Ground water monitoring will also be implemented and data from
sampling activities will reflect the effectiveness of this remedy over time.
ALTERNATIVE 5: SOLIDIFICATION / STABILIZATION & DNAPL RECOVERY
TRENCH SYSTEM
Alternative 5 involves the excavation and immobilization of MCW Site contaminants using
stabilization/solidification techniques. Solidification/stabilization, using the moisture content of
the soil or additional moisture sources and the properties of the reagent additives, binds or
immobilizes the contaminants in the soil, eliminating the potential for further migration.
On-site and Off-site soil will be stockpiled prior to treatment. The excavated soil is then
screened to ensure treatment efficacy and then may be treated in one of two ways:
1) The soil will be slurried in a pug mill or cement mixer. Proprietary reagents and portland
cement will be added. The mixture will be pumped into the excavation and allowed to
solidify in place; or,
2) The soil will be replaced in the lined excavation area, pneumatically injected with reagents,
stabilized, and then compacted. The process'will continue until all soil is solidified.
Before the treated soil is solidified/stabilized into the excavations, a DNAPL Recovery Trench
System will be installed. Following installation of the recovery trench system, the excavations
will be solidified/stabilized with the treated soil. A layer of topsoil will be placed over the
treated soil, and the area will be seeded.
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Institutional controls will be implemented to ensure that future individuals will not be exposed to
the Site contaminants. Ground water monitoring will also be implemented and data from
sampling activities will reflect the effectiveness of this remedy over time.
ALTERNATIVE 6: CAPPING & DNAPL RECOVERY TRENCH SYSTEM
Alternative 6 will involve the construction of a cap over MCW Site contaminants.
Capping is a containment technology that limits exposure to contaminated media. Capping also
limits migration of contaminants by minimizing infiltration of water into the contaminated soil.
To meet the goals, the cap must withstand climatic extremes; resist water and wind erosion;
resist slumping, cracking, slope failure, and creep; and resist disruptions caused by plants and
animals. A cap is characterized by a multi-layer configuration, and each layer performs a task.
From top to bottom, these layers are: protective, barrier; and grading.
A protective layer of topsoil covers the cap. The purpose of the protective layer is to protect the
underlying barrier layer from freeze-thaw cycles and desiccation cracks, and provide a medium
for root growth. The topsoil also facilitates the growth of vegetation, which is helpful in
reducing soil erosion, increasing structural stability of the cap, and reducing infiltration by
increasing evapotranspiration.
The barrier layer provides a barrier for water infiltration, and is usually constructed of clay over a
synthetic liner. The clay must be capable of being compacted to produce a suitably low
hydraulic conductivity.
The lowest layer, the grading layer, provides a stable surface on which the barrier layer can be
constructed. The thickness depends on the stability of the underlying soil.
Contaminated soil from Off-site areas will be excavated, denatured, and spread over the area of
On-site contaminated soil prior to construction of the cap. Off-site excavations will be backfilled
with imported clean fill material.
Before the construction of the cap, a DNAPL Recovery Trench System will be installed.
Following installation of the recovery trench system, the cap will be constructed.
Institutional controls will be implemented to ensure that future individuals will not be exposed to
the Site contaminants. Ground water monitoring will also be implemented and data from
sampling activities will reflect the effectiveness of this remedy over time.
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ALTERNATIVE 7: LANDFILL DISPOSAL & DNAPL RECOVERY TRENCH SYSTEM
Alternative 7 will include the excavation, loading, transporting, and disposal of contaminated
On-site and Off-site soil in a RCRA permitted landfill.
The excavated soil will be loaded into trucks and transported to the RCRA Subtitle C landfill.
Off-site contaminated soil in the north and south streams will be accessed by temporarily
rerouting stream flow and then excavated. On-site and Off-site excavations will be backfilled
with imported clean fill material.
Before the imported clean fill material is backfilled into the excavations, a DNAPL Recovery
Trench System will be installed. Following installation of the recovery trench system, the
excavations will be backfilled with the imported clean fill material. A layer of topsoil will be
placed over the fill material, and the area will be seeded.
Institutional controls will be implemented to ensure that future individuals will not be exposed to
the Site contaminants. Ground water monitoring will also be implemented and data from
sampling activities will reflect the effectiveness of this remedy over time.
OSHA REQUIREMENTS
Under all alternatives, employers of cleanup workers are required to comply with all applicable
occupational safety and health standards promulgated under Section 5 of the Occupational Safety
and Health Act. The requirements include the Occupational Safety and Health Administration
(OSHA) standards under 29 CFR 1910.120 that were developed to maintain the health and safety
of employees involved in hazardous waste operations or hazardous waste operations and
emergency response. These standards are applicable to employees engaged in cleanup activities
at designated CERCLA sites regulated under 40 CFR 300 Subpart F; employees engaged in
RCRA closure activities conducted under 40 CFR 265 Subpart G; employees at those sites
similar to CERCLA sites that have been designated for cleanup by a state or local agency;
employees at RCRA treatment, storage, and disposal facilities; and employees engaged in
emergency response actions at all sites. Because excavation and construction related activities at
the MCW Site involve the potential for workers to be exposed to hazardous working conditions
that may include toxic and hazardous substances and hazardous wastes, any remedial actions
must be performed in accordance with applicable OSHA standards.
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COMPARATIVE ANALYSIS OF REMEDIAL ALTERNATIVES /
STATUTORY DETERMINATIONS
A detailed analysis of remedial action alternatives is required by the NCP (40 CFR 300.430
[e][9]). Section 121 of the Superfund statute, CERCLA, established five principal requirements
for the selection of remedies. According to these statutory requirements that guide the evaluation
of remedial alternatives a remedial action must achieve the following objectives:
Protect human health and the environment;
Comply with applicable or relevant and appropriate requirements (ARARs) unless a waiver is
justified;
Be cost effective;
Utilize permanent solutions and alternative treatment technologies or resource recovery
technologies to the maximum extent practicable; and,
Satisfy a preference for treatment as a principal element, or provide an explanation in the
ROD was to why this preference was not met.
USEPA has developed nine criteria to be used to evaluate remedial alternatives to ensure all
important considerations are factored into remedy selection decisions. These criteria are derived
from the statutory requirements of Section 121 (as stated above), particularly the long-term
effectiveness and related considerations specified in Section 121(b)(l), as well as other additional
technical and policy considerations that have proven to be important for selecting among
remedial alternatives. The nine evaluation criteria can be classified into the categories of
threshold criteria, primary balancing criteria, and modifying criteria. A description of evaluation
criteria categories and the nine evaluation criteria follows:
THRESHOLD CRITERIA
The two most important criteria are statutory requirements that must be satisfied by any
alternative in order for it to be eligible for selection. These two threshold criteria are:
1) Overall Protection of Human Health and the Environment: The overall protection of human
health and the environment is evaluated for each alternative on the basis of the alternative's
ability to reduce the risk of exposure to contaminants from potential exposure pathways
through engineering or institutional controls. Each alternative is also examined to determine
whether it creates unacceptable short-term risks to human health.
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2) Compliance with ARARs: This criterion evaluates each alternative's compliance with
action-specific, location-specific, and chemical-specific ARARs. Section 121(d) of
CERCLA states that remedial actions must attain or exceed ARARs. ARARs are derived
from both Federal and State environmental facility siting laws and include regulations,
standards, criteria, or limitations promulgated under federal or state laws. State standards
that constitute ARARs are those laws that are promulgated, substantive in nature, more
stringent than federal requirements, consistently applied, and identified by the State in a
timely manner.
The ARARs identified by USEPA, DOI, USF&W, NOAA, and LDEQ, that are applicable to
the MCW Site are the following:
a) Action specific ARARs:
Action specific ARARs are typically technology or activity based requirements
applicable to actions involving special categories of wastes. Action specific requirements
are usually triggered by certain remedial activities that may be a component of the overall
preferred cleanup alternative. The following action specific requirements must be in
compliance:
i) Solid Waste Requirements:
Solid waste, such as non-hazardous contaminated waste soils and debris generated at
the MCW Site through industrial activities, is defined under the Louisiana
Administrative Code (LAC) 33:VII.Chapter 1, identified by these regulations under
LAC 33:VII.Chapter 3, and subject to the requirements of RCRA Subtitles D and C
and the provisions of the Louisiana Solid Waste Regulations (LSWR). These
regulations require that persons generating, collecting, transporting, storing,
processing, and disposing of solid waste comply with the notification requirements
for facilities and landfills under the LSWR. LAC 33:VII.Chapter 7 specifies the
reporting, notification, waste-testing, waste code assignment, waste accumulation,
and transporter requirements with which all generators of industrial solid waste must
comply.
ii) Hazardous Waste Requirements:
RCRA allows any State to administer and enforce a hazardous waste program under
Federal authorization. The Hazardous and Solid Waste Amendments of 1984
expanded the scope of RCRA by adding new corrective action requirements, land
disposal restrictions, and technical requirements.
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Rules and regulations for a hazardous waste management system were established by
the Louisiana Department of Natural Resources (LDNR) under LAC 33 :V.
Generators of hazardous waste in Louisiana must comply with the rules set forth by
LDNR in LAC 33:V.Chapter 11 (40 CFR 261 and 262). These regulations establish
the requirements for hazardous waste determination, USEPA generator identification,
waste manifests and shipments, pre-transport activities, and generator record keeping
and reporting activities. The disposal of wastes from the MCW Site designated as
RCRA characteristic or listed hazardous waste (D018 and F034) at a RCRA Subtitle
C landfill must also comply with LAC 33:V.Chapter 109; LAC 33:V.Chapter 49; and
LAC33:V.Chapter22.
Thermal treatment technologies that generate F034 hazardous soil and debris waste
produce a residue that is subject to the requirements of LAC 33:V.Chapter 22. This
residue will not require further treatment prior to disposal.
iii) Air Quality Requirements:
Under the provisions of the Clean Air Act, LAC 33:III.Chapter 1 states that sources of
emissions existing partially or wholly within the State of Louisiana must comply with
the regulations, air quality standards, and emission limitations of that Part. Under
LAC 33:III.Chapter 51, in accordance with Louisiana Revised Statutes (LRS)
30:2060, air emissions from a stationary major source that are generated during the
remediation of a RCRA, CERCLA, or any non-regulated inactive or abandoned waste
site are, at a minimum, exempt from permitting requirements. However, LDEQ
technical standards and applicable RCRA regulations under 40 CFR 264 Subparts O
and 40 CFR 265 Subparts O and P must be met if the On-site stationary thermal
treatment unit is defined as a major source and has the potential to emit 10 tons per
year or more of any toxic air pollutant (TAP) or 25 tons per year or more of any
combination of TAPs.
Remedial cleanup actions resulting in the generation of airborne paniculate matter
from the excavation of contaminated soils, earth moving, and regrading must be
evaluated under LAC 33:III.Chapter 13. These regulations call for the control of
fugitive emissions by taking measures to prevent paniculate matter and suspended
paniculate matter from becoming airborne. Air emissions from small sources must be
less than 5 tons per year of a regulated pollutant, such as PAHs. Also, air emissions
cannot exceed the maximum allowable emission rate for any hazardous air pollutant
or TAP.
62
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iv) Water Quality Requirements:
The Clean Water Act (33 U.S. Code 1251 to 1376), as amended by the Water Quality
Act of 1987 (Public Law 100-4-103), provides authority for each state to adopt water
quality standards designed to protect beneficial uses of each water body and requires
states to designate uses for each water body. Discharges will meet storm water and
wastewater discharge monitoring requirements established by LDEQ.
v) Department of Transportation Requirements:
As required by the U.S. Department of Transportation (49 CFR 171), hazardous
materials, such as hazardous wastes and environmentally hazardous substances that
may be transported off the MCW Site, cannot be transported in interstate and
intrastate commerce, except in accordance with the requirements of 49 CFR 171
Subpart C. Hazardous wastes or environmentally hazardous substances transported
within the state must comply with the applicable packaging, labeling, marking, and
placarding requirements of 49 CFR 171 Subpart C and/or Louisiana Hazardous
Material Regulations Subchapter C, and the Department of Public Safety under LAC
33:V, Subpart 2, Chapter 101.
b) Location Specific ARARs:
Location specific ARARs are restrictions placed on remedial activities solely on the basis
of the location of the remedial activity. Some examples of locations that might prompt a
location specific ARAR include sensitive ecosystems or habitats, floodplains, and areas
of historical significance. Because Off-site areas have incurred impacts by releases of
contaminants from the On- site area, the following location specific ARARs for the Off-
site areas are applicable:
i) Floodplain Management Order, Executive Order No. 11988:
This Executive Order (40 CFR 6 Appendix A) dictates that federally funded or
authorized actions within the 100-year floodplain avoid, to the maximum extent
possible, adverse impacts associated with development of a floodplain. Compliance
with this requirement is detailed in USEPA's "Policy of Floodplains and Wetlands
Assessments for CERCLA Actions."
ii) Protection of Wetlands Order, Executive Order No. 11990:
The requirements of this Executive Order (40 CFR 6 Appendix A) mandate that
federal agencies avoid, to the extent possible, the adverse impacts associated with the
destruction or loss of wetlands and avoid support of new construction in wetlands if a
practicable alternative exists.
63
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c) Chemical specific ARARs:
Chemical specific ARARs are usually health or risk based numerical values or
methodologies that, when applied to site specific conditions, result in the establishment of
numerical values. These values establish the acceptable amount or concentration of a
chemical that may be found in, or discharged to, the environment. Potential exposure
pathways for contamination include air, soil, and ground water. The State of Louisiana
has not identified MCL values for PAHs. Also, no Federal or State of Louisiana
regulatory cleanup standards have been promulgated for soil; therefore, risk based criteria
have been identified for this media (see SITE RISKS). The following chemical specific
ARAR has been identified:
i) USEPA's National Primary Drinking Water Standards:
Assuming the water beneath and in the vicinity of the MCW Site is a potential
drinking water source, CERCLA requires that MCLs for inorganics and organics
generally be considered "relevant and appropriate" for ground water remediation.
However, domestic use of the ground water within the shallow clayey-silt saturated
zone is not feasible because the hydrogeologic investigation does not support any
assumption that ground water in this contaminated zone could ever yield sufficient
quantities of water to be a viable source for domestic use. Therefore, the remedial
cleanup will ensure drinking water MCLs are met for the viable water aquifers located
deeper beneath the contaminated saturated zones.
PRIMARY BALANCING CRITERIA
Five primary balancing criteria are used to identify and measure the major cleanup abilities
between the remedial alternatives. These criteria undergo comparison and evaluation to identify
the preferred alternative and to select the final remedy. The five primary balancing criteria are:
1) Long-term Effectiveness and Permanence: Long-term effectiveness and permanence are
evaluated for each alternative on the basis of the magnitude of residual risk and the adequacy
and reliability of controls used to manage remaining waste after response objectives have
been achieved. Alternatives that offer long-term effectiveness and permanence halt (or
otherwise mitigate) any potential for Off-site contaminant transport and minimize the need
for future engineering controls.
64
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2) Short-term Effectiveness: The evaluation of alternatives for short-term effectiveness takes
into account protection of remedial workers, members of the community, and the
environment during implementation of the RA and the time required to achieve cleanup
performance goals. Time estimates are based on projected availability of materials and labor,
weather, the ability to create and receive adequate and authorized access, and the availability
of required utilities.
3) Reduction of Mobility, Toxicity, or Volume through Treatment: The statutory preference is
to select a remedial alternative that employs treatment to reduce the mobility, toxicity, or
volume of hazardous substances. The degree to which alternatives employ recycling or
treatment is assessed, including how treatment is used to address the principal threats posed
by the Site.
4) Implementability: Each alternative is evaluated with respect to the technical and
administrative feasibility of implementing the alternatives as well as the availability of
necessary equipment and services. This criterion includes such items as: the ability to obtain
services, capacities, equipment, and specialists necessary to construct components of the
alternative; the ability to operate and monitor the performance and effectiveness of
technologies; and, the ability to obtain necessary approvals from other agencies.
5) Cost: Each alternative is evaluated for cost effectiveness against the other alternatives.
Accuracy of present worth costs is +50/-30 percent. Detailed cost estimates are derived from
current information, including vendor quotes, conventional cost-estimating guides, and costs
associated with similar projects. The actual cost of the project will depend on labor and
material costs, site conditions, competitive market conditions, the final project scope, and the
implementation schedule at the time the remedial activities are initiated.
MODIFYING CRITERIA
These criteria were considered fully after the formal public comment period on the Proposed
Plan was completed. The USEPA have also worked with the State and the community
throughout the MCW Site cleanup project to ensure an agreeable cleanup remedy selection for all
parties. The two modifying criteria are:
1) State Acceptance: The USEPA selected cleanup alternative should be acceptable to the State
and its support agencies. In support of the ROD by USEPA, the State will issue a letter
officially concurring on the selection of the cleanup remedy and sign a Superfund State
Contract after the ROD is issued, whereby the State agrees to a 10% funding match for the
cost of the selected alternative.
65
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2) Community Acceptance: The concerns of the community should be considered when
selecting a remedial alternative. Much information has been exchanged with the area
residents and community leaders concerning the MCW Site. This criteria spells out the
formal acceptance of the community and will be based on comments received from residents
and local officials during the Proposed Plan public comment period.
Information on how the various remedial alternatives compared with each other on the threshold,
primary balancing, and modifying evaluation criteria can be found on Table 4.
66
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TABLE 4:
COMPARATIVE ANALYSIS OF ALTERNATIVES
THRESHOLD CRITERIA EVALUATION
ALTERNATIVE
OVERALL PROTECTION OF HUMAN HEALTH AND THE
.,'..;.;;. ENVIRONMENT .
COMPLIANCE
WITHARARs
ALTERNATIVE 1:
NO FURTHER ACTION
ALTERNATIVE 2:
INSTITUTIONAL CONTROLS /
GROUND WATER MONITORING
ALTERNATIVE 3:
LOW TEMPERATURE THERMAL
DESORPTION ft DNAPL
RECOVERY TRENCH SYSTEM
ALTERNATIVE 4:
INCINERATION & DNAPL
RECOVERY TRENCH SYSTEM
ALTERNATIVE 5:
SOLIDIFICATION /
STABILIZATION & DNAPL
RECOVERY TRENCH SYSTEM
ALTERNATIVE 6:
CAPPING ft DNAPL RECOVERY
TRENCH SYSTEM
ALTERNATIVE 7:
LANDFILL DISPOSAL ft DNAPL
RECOVERY TRENCH SYSTEM
Not protective of human health or the environment because
risk of contact with On-site and Off-site contaminants
remains.
Not protective of human health or the environment because
risk of contact with Off-site contaminants remains.
Provides overall protection of human health and the
environment by thermally treating On-site and Off-site
wastes.
Provides overall protection of human health and the
environment by thermally treating On-site and Off-site
wastes.
Provides overall protection of human health and the
environment by immobilizing On-site and Off-site wastes.
Provides overall protection of human health and the
environment by encapsulation of contaminants via a
containment barrier.
Provides overall protection of human health and the
environment by removal of contaminated soil for landfill
disposal.
No
No
Yes
Yes
Yes
Yes
Yes
67
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TABLE 4 (Continued)
COMPARATIVE ANALYSIS OF ALTERNATIVES
PRIMARY BALANCING CRITERIA EVALUATION
ALTERNATIVE
LONG-TERM EFFECTIVENESS
AND PERMANENCE
SHORT-TERM;.
EFFECTIVENESS
REDUCTION OF MOBILITY,
TOXICITY, AND VOLUME
THROUGH TREATMENT
IMPLEMENTABILITY
COST (PRESENT
WORTH $)
ALTERNATIVE I:
NO FURTHER ACTION
ALTERNATIVE 2:
INSTITUTIONAL
CONTROLS /GROUND
WATER MONITORING
ALTERNATIVE 3:
LOW TEMPERATURE
THERMAL
DESORPTION &
DNAPL RECOVERY
TRENCH SYSTEM
Long-term risks would increase
because On-sitc contaminants
may migrate Off-site; risk of
contact with soil and sediment
remains.
Long-term risks would increase
because On-site contaminants
may migrate Off-site; risk of
contact with soil and sediment
remains.
Long-term risks to future users
reduced because wastes are
removed from On-site and Off-
site areas; DNAPL would be
contained and/or recovered
from the Site.
No short-term effects from
remediation because there is
no remediation; does not
achieve remedial action
objectives.
Security fencing and signs
would limit access to the On-
site area; potential for
exposure to Off-site
contaminants would remain.
Minimal risks to Site workers;
wastes would be treated in a
relatively short period of
time; gravity drainage of
DNAPL would require several
years.
No change in mobility,
toxicity, or volume because
there is no treatment.
No change in mobility,
toxicity, or volume because
there is no treatment.
Mobility, toxicity, and volume
of principal threat wastes
would be eliminated by thermal
treatment; volume of DNAPL
would be reduced by recovery
and disposal.
Nothing to implement.
100,000
Easily implemented.
1.027,000
Full-scale technology;
numerous vendors with
mobile units available.
18,500,000
68
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TABLE 4 (Continued)
ALTERNATIVES EVALUATION COMPARISON
^^^^^^^^^^^^^^^^MMMMIMB^HM^^^^M^^
PRIMARY BALANCING CRITERIA EVALUATION
ALTERNATIVE
LONG-TERM EFFECTIVENESS
AND PERMANENCE
SHORT-TERM
EFFECTIVENESS
REDUCTION OF MOBILITY,
TOXIOTY, AND VOLUME
THROUGH TREATMENT
IMPLEMENTABILITY
COST (PRESENT
WORTH $)
ALTERNATIVE 4:
INCINERATION &
DNAPL RECOVERY
TRENCH SYSTEM
ALTERNATIVE 5:
SOLIDIFICATION /
STABILIZATION &
DNAPL RECOVERY
TRENCH SYSTEM
Long-term risks to future users
reduced because wastes are
removed from On-site and Off-
site areas; DNAPL would be
contained and/or recovered
from the Site.
Effectively immobilizes
contaminants; stabilized soil
will be backfilled; continued
ground water monitoring will
assess the long-term
effectiveness; DNAPL would be
contained and/or recovered
from the Site.
Minimal risks to Site workers;
wastes would be treated in a
relatively short period of
time; gravity drainage of
DNAPL would require several
years.
Minimal risks to Site workers;
wastes would be treated in a
relatively short period of
time; gravity drainage of
DNAPL would require several
years.
Mobility, toxicity, and volume
of principal threat wastes
would be eliminated by thermal
treatment; volume of DNAPL
would be reduced by recovery
and disposal.
Mobility and toxicity of wastes
would be reduced by
immobilization; solidified soil
volume would increase 25% -
30%; volume of DNAPL would
be reduced by recovery and
disposal.
Full-scale technology;
numerous vendors with
mobile units available.
30,700,000
Full-scale technology;
numerous vendors with
mobile process equipment
available.
15,600,000
69
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TABLE 4 (Continued)
ALTERNATIVES EVALUATION COMPARISON
PRIMARY BALANCING CRITERIA EVALUATION
ALTERNATIVE
LONG-TERM EFFECTIVENESS
AND PERMANENCE
SHORT-TERM
EFFECTIVENESS
REDUCTION OF MOBILITY,
TOXICTTY, AND VOLUME
THROUGH TREATMENT
IMPLEMENTABIUTY
COST (PRESENT
WORTHS)
ALTERNATIVE 6:
CAPPING & DNAPL
RECOVERY TRENCH
SYSTEM
ALTERNATIVE 7:
LANDFILL DISPOSAL
& DNAPL RECOVERY
TRENCH SYSTEM
Long-term risks to future users
are reduced due to institutional
controls and maintenance of
the cap; DNAPL would be
contained and/or recovered
from the Site.
Long-term risks to future users
are reduced because wastes are
removed from the Site; DNAPL
would be contained and/or
recovered from the Site.
Minimal risks to Site workers;
waste containment barrier
would be installed and
institutional controls would
be implemented in a relatively
short period of time; gravity
drainage of DNAPL would
require several years.
Minimal risks to Site workers;
excavated wastes will be
transported and disposed to a
landfill in a relatively short
period of time; gravity
drainage of DNAPL would
require several years.
No reduction of volume or loxicity of
principal threat wastes; volume of
DNAPL would be reduced by
recovery and disposal.
Not a treatment technology,
therefore, no reduction of
mobility, toxicity, or volume;
volume of DNAPL would be
reduced by recovery and
disposal.
Full-scale technology;
numerous vendors with
equipment; materials
available.
12,330,000
Full-scale technology;
numerous vendors with
equipment; materials
available.
25,850.000
70
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TABLE 4 (Continued)
COMPARATIVE ANALYSIS OF ALTERNATIVES
MODIFYING CRITERIA EVALUATION
ALTERNATIVE
STATE ACCEPTANCE
COMMUNITY ACCEPTANCE
ALTERNATIVE 1:
NO FURTHER ACTION
ALTERNATIVE 2:
INSTITUTIONAL CONTROLS /
GROUND WATER MONITORING
ALTERNATIVE 3:
LOW TEMPERATURE THERMAL
DESORPTION & DNAPL
RECOVERY TRENCH SYSTEM
ALTERNATIVE 4:
INCINERATION & DNAPL
RECOVERY TRENCH SYSTEM
ALTERNATIVE 5:
SOLIDIFICATION /
STABILIZATION &. DNAPL
RECOVERY TRENCH! SYSTEM
ALTERNATIVE 6:
CAPPING & DNAPL RECOVERY
TRENCH SYSTEM
ALTERNATIVE 7:
LANDFILL DISPOSAL & DNAPL
RECOVERY TRENCH SYSTEM
Not Applicable.
Nol Applicable.
State of Louisiana concurrence letter
to USEPA. dated July 13, 1998,
supports the selection of cleanup
remedy as presented in the ROD.
Not Applicable.
Not Applicable.
Not Applicable.
Not Applicable.
Not Applicable.
Not Applicable.
St. Tammany Parish Police Jury adopts
Resolution Police Jury Series No. 98-8594 on
March 19, 1998, unanimously supporting
USEPA's preferred cleanup alternative as
presented in the Proposed Plan and later as the
selected cleanup remedy in the ROD.
Not Applicable.
Nol Applicable.
Not Applicable.
Not Applicable.
71
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SELECTED REMEDY
USEPA chose Alternative 3: Low Temperature Thermal Desorption & DNAPL Recovery Trench
System as the preferred remedial alternative for cleanup of the MCW Site.
This alternative entails treating contamination by using the LTTD technology. This LTTD
component of the selected cleanup remedy will address the principal threat wastes at the MCW
Site. Cleanup of creosote liquid source materials located in approximately 75,000 cubic yards of
contaminated soil and sediment removes the principal threat to human health and the
environment and satisfies the statutory preference for treatment. On-site and Off-site soil and
sediment will be excavated and stockpiled within the On-site area. LTTD process equipment
will also be operated in the On site area. Once the contaminated soil is treated, it will be
reconstituted and used as backfill in the excavations. The backfilled areas will be revegetated
with native grasses, shrubs, and trees.
The DNAPL Recovery Trench System will contain and recover, to the maximum extent
practicable, the low teachability creosote source materials trapped in the saturated shallow
clayey-silt zone. This system will prevent the migrating of contaminants into the viable aquifers
and reduce and/or eliminate the source contaminants.
Institutional controls in the form of deed notices will be implemented to provide notice to current
and future owners that extraction and use of the contaminated ground water in the saturated
zones should be avoided.
Ground water monitoring will also be implemented by collection of samples from Site
monitoring wells and nearby residential water supply wells. Data from ground water monitoring
will reflect the effectiveness of this selected remedy over time.
A conceptual process flow diagram of the low temperature thermal desorption unit is found on
Figure 4.
A conceptual design of the DNAPL recovery trench system is found on Figure 5.
72
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FIGURE 4: LOW TEMPERATURE THERMAL DESORPTION
PROCESS FLOW DIAGRAM -
See Region
73
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FIGURES: DNAPL RECOVERY TRENCH SYSTEM
See Region
74
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ANALYSIS OF' THE SELECTED CLEANUP ALTERNATIVE (ALTERNATIVE #3)
An analysis summary of the selected cleanup alternative compared to the nine evaluation criteria
follows:
1) Overall Protection of Human Health and the Environment: This alternative will provide both
short-term and long-term protection of future users of the MCW Site and nearby residents by
eliminating exposure to MCW Site contaminants in the soil, sediment, and surface water.
This alternative may pose short-term risks to site workers, including dermal contact with
contaminated soil, inhalation of vapors and dust, and dangers associated with operating
material-handling and processing equipment.
2) Compliance with ARARs: The LTTD unit and DNAPL Recovery Trench System will be
designed and operated to comply with all action specific, location specific, and chemical
specific ARARs identified in this ROD.
3) Long-term Effectiveness and Permanence: Treatment by LTTD will effectively remove
liquid creosote source contaminants from the soil and sediments and address the principal
threats posed by that contamination. Low teachability creosote materials remaining in the
shallow clayey-silt saturated zone will be contained and recovered via the DNAPL Recovery
Trench System. Residual material from the trench system will be collected and taken to a
RCRA facility for disposal. Because this RA alternative removes the source contaminants, it
eliminates risks associated with direct contact with or migration of those contaminants.
Consequently, it provides long-term health protection to future Site users.
3) Short-term Effectiveness: The LTTD alternative will address the MCW Site contaminants in
soil, sediment, and surface water in a relatively short period of time. However, the selected
remedy, will not provide short-term results with respect to the low teachability creosote
within the shallow clayey-silt saturated zone. DNAPL drainage and collection into the
DNAPL Recovery Trench System may require several years to complete. This alternative
involves potential short-term risks that result from handling contaminated soil. Other
short-term risks include the potential for exposure of workers and nearby residents to fugitive
emissions during excavation and treatment. Appropriate dust control measures and worker
personal protective equipment will be required to mitigate these short-term risks.
4) Reduction of Toxicity, Mobility, or Volume Through Treatment: Implementation of the
LTTD treatment component of the selected remedy will significantly reduce the toxicity,
mobility, and volume of the principal threat wastes in the soil and sediment by thermal
elimination of the creosote source contamination. The DNAPL Recovery Trench System
will be implemented to address the remaining low-level threat wastes in the shallow clayey-
silt saturated zone.
75
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5) Implementability: The LTTD alternative has been used successfully at other Superfund sites
to treat similar organic contaminants in soil and sediments. Implementation of this remedy
will be straightforward since numerous vendors offer a variety of mobile LTTD units. Local
infrastructure will support the use of this technology; reliable electricity and water supply are
the primary requirements. Operation of the LTTD unit will require engineering measures to
control air emissions, fugitive dust, runoff, erosion, and sedimentation. The DNAPL
Recovery Trench System has also been used successfully at other Superfund sites to contain
and recovery similar low teachability wastes within saturated zones. Operation of the
DNAPL Recovery Trench System is based on a passive system of gravity drainage and
collection.
6) Cost: The total cost for the selected remedy is about $18,500,000. The total cost estimate
includes treatment costs of the soils and sediment, and the remaining funds to prepare and
establish the necessary infrastructure to support the alternative and maintain and operate the
site over the life span of the alternative. The LTTD & DNAPL Recovery Trench System
cleanup remedy is the most cost effective alternative in achieving protection of human health
and the environment through treatment of principal threat wastes and containment/recovery
of low level threat wastes. This cost estimate can be found in Table 5.
7) State Acceptance: The State of Louisiana has reviewed the ROD and concurs with the
selection of the LTTD & DNAPL Recovery Trench System cleanup remedy (LDEQ letter to
USEPA dated July 13,1998, see APPENDIX). State acceptance of the final remedy
selection is formalized, after the ROD is issued, through the signing of a State Superfund
Contract with USEPA.
8) Community Acceptance: Public comments received during the Proposed Plan comment
period are addressed under the RESPONSIVENESS SUMMARY section of the ROD. The
community at this Site appears to agree with USEPA in the selection of the LTTD & DNAPL
Recovery Trench System cleanup remedy. As representatives of the parish in which the
MCW Site is located, the St. Tammany Police Jury has also unanimously passed a resolution
(Resolution P.J.S. No. 98-8594, see APPENDIX) in support of USEPA's cleanup alternative.
76
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TABLE 5:
COST ESTIMATE FOR THE SELECTED REMEDY
Description j Unit j Crai/Uuir j Quantity j Subtotal* j Activity TcUS*
General Conditions
Communications (Radios)
Site Project Manager (Prime)
Site Project Manager
Superintendent (Prime)
Site Engineer
Technician
Busell Water Well (P&A old well
and drill new one)
Site Office (20 ft x 8 ft)
Site Office
Storage Trailer
Portable Toilets
Construction Signs, Photographs
Surveying (crew)
Site Security Office
Uniformed Watchman
Installation of Electrical Pole,
Transformer, Service Connections
Mobilization and Demobilization
Each
MWK
MWK
MWK
MWK
MWK
LS
MNTH
MNTH
MNTH
MNTH
LS
DAY
MNTH
HR
LS
LS
S386.82
$1,929.69
$2,105.13
$1,841.98
$2,105.13
$526.29
$120,000.00
$231.88
$586.83
$126.20
$122.80
$28,437.99
$635.00
$231.88
$13.00
$13,000.00
$365,000.00
12
104
104
104
104
208
1
24
48
96
96
1
480
24
7,300
1
1
$4,641.84
$200,687.76
$218,933.52
$191,565.92
$218,933.52
$109,468.32
$120,000.00
$5,565.12
$28,167.84
$12,115.20
$11,788.80
$28,437.99
$304,800.00
$5,565.12
$94,900.00
$13,000.00
$365,000.00
Subtotal $1,933,570.95
Clear and Grub ~ f. " ' : *.?** .- . -. > - -; ,; :
Clear Trees to 12-in diameter (D8
CAT)
Clear Trees to 24-in diameter (D8
CAT)
Stump Removal >6 in to <12 in
Stump Removal > 12 in to <24 in
Heavy Brush Clearing, Chipping
Each
Each
Each
Each
AC
$9.09
$12.50
$30.95
$33.70
$1,540.50
200
100
200
250
6.7
$1,818.00
$1,250.00
$6,190.00
$8,425.00
$10,249.06
77
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TABLE 5 (Continued)
COST ESTIMATE FOR THE SELECTED REMEDY
Description
Dozer Grubbing and Stacking
Stump Chipping
Subtotal
Demolition
Concrete Dump Charge
Building Demolition
6-in Thick Concrete Demolition
8-in Thick Concrete Demolition
(Reinforced)
Building Debris Disposal
Subtotal
Fencing, Gates, and Signige
Security Fence, Signs, Gates
Subtotal
Decontamination Facilities
Water Supply Well
Pad Subgrade Preparation
Compact Subgrade, 2 Lifts
6 in x 6 in Concrete Curb
26 in x 26 in, 5-ft Deep Area Drain
with Grate
10-in Structural Slab on Grade
36,000-gpd, Packaged Water
Treatment Plant
5,000-gal Tank
20,000-gal Horizontal Tank
3,000-gal Aboveground Tank
1,800-psi Pressure Washer, 6 HP,
4.8 gpm
Unit
CY
LS
CY
CF
CY
CY
LS
LF
Each
CY
CY
LF
Each
SF
Each
Each
Each
Each
Each
Cost/Unit"
$2.25
$16,000.00
'*' /*:>/'
$18.40
$0.11
$36.75
$120.90
$38,700.00
-r . "... _ .,...,-. ...*.;.-- ,*».*,- _ ..;..;
$25.00
$100,000.00
$2.81
$0.34
$1.80
$2,398.25
$7.15
$31,922.78
$4,652.17
$21,983.65
$2,900.80
$3,441.75
Quantity
30,000
1
350
100,000
250
100
1
:- : :.";: : . .,
4,804
1
300
300
264
4
6,11
4
Subtotal*
$67,500.00
$16,000.00
$6,440.00
$11,000.00
$9,187.50
$12,090.00
$38,700.00
- -- ..... - ;-: .v-
$120,100.00
. : - ..... ..-::" ':
$100,000.00
$843.00
$102.00
$475.20
$9,593.00
$43,693.65
$31,922.78
$4,652.17
$21,983.65
$2,900.80
$13,767.00
Activity Total*
$111,432.06
$77,417.50
$120,100.00
78
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TABLE 5 (Continued)
COST ESTIMATE FOR THE SELECTED REMEDY
Description
1,800-psi Pressure Washer, 4.5 gpm
3,000-psi Pressure Washer, 4.5 gpm
Operation of Pressure Washer
Operation of Steam Cleaner
500-gpm Sump Pump
umi
Each
Each
HR
HR
Each
VU3I/UUH
$3,671.74
$3,925.50
$37.38
$51.65
$3,848.61
Vuiiuuij
4
2
5,760
4,800
1
SsbteiaT
$14,686.96
$7,851.00
$215,308.80
$247,920.00
$3,848.61
A _Ai-.tA_. nn^A.ia |
AVUVIIJ 1UUSI
Subtotal $719,548.62
Recovery Trench System , >
950 CAT, 3 CY, Backfill with
Excavated Material
Crushed Stone, '/» in to J/4 in
Trench Bottom Liner
Trench Side Fabric Filter
Compaction
CAT 235, 15 ft - 25 ft Trench in
Sheeting
Dewatering
6 in x 24 in Formed Concrete Curb
and Gutter
6-in Mesh Reinforced Slab on Grade
Electrical Power Poles
Electrical Overhead Power Line
Electrical 30-ft Lighting Pole
Electrical 400- Wan Sodium Lights
Electrical 2-in PVC Conduit
Electrical 3-Wire Cable
Electrical Distribution, Circuit
Breaker Box
Treatment Building
8-in Class 200 PVC Piping
CY
CY
SF
SF
CY
CY
CY
LF
SF
Each
LF
Each
Each
LF
LF
LS
SF
LF
$1.04
$21.53
$1.05
$0.85
$2.34
$3.05
$1.47
$12.17
$3.84
$497.07
$10.43
$1,735.83
$921.54
$1.93
$3.99
$4,800.00
$37.50
$14.44
196,105
15,407
17,400
320,000
196,105
211,497
196,105
648
2,916
6
300
6
12
2,000
2,000
1
600
2,700
$203,949.20
$331,721.48
$18,270.00
$272,000.00
$458,885.70
$645,065.85
$288,274.35
$7,886.16
$11,197.44
$2,982.42
$3,129.00
$10,414.98
$11,058.48
$3,860.00
__ $7,980.00
$4,800.00
$22,500.00
$38,988.00
79
-------
TABLE 5 (Continued)
COST ESTIMATE FOR THE SELECTED REMEDY
Description
24 ft x 60 in Wet Well Lift Station
5,000-gal Aboveground Tank
8-in PVC Schedule 80, Well Screen
Product Recovery Pump and
Controls
Restricted Area Protection
Creosote Recovery Piping and
Utility Trench Box (2 ft x 3 ft)
Subtotal
Oil/Water Separation Facilities
CAT 225 Trenching
950 CAT, Backfill with Excavated
Material
Compaction
6 in x 24 in Formed Concrete Curb
and Gutter
6-in Structural Slab on Grade
Packaged 20-gpm Oil/Water
Separator
550-gal Sump
20-gpm Pump-out Unit with
Controls
4-in Carbon Steel Piping
Subtotal
Storage Tank Facilities
Tank Finings
8 in x 7.5 in Manhole and Cover
Tank Piping and Finings
Subtotal
Unit
Each
Each
LF
Each
Each
LF
'. . ... i'. . . : . :
CY
CY
CY
LF
SF
Each
Each
Each
LF
$' ' '
Each
Each
LS
Cost/Unlf
$15,095.22
$4,652.17
$55.87
$18,550.25
$275.00
$17.09
......... ..-,- .._ .. - - v i"- ;; , --;;:^ -.*
$0.79
$1.04
$2.33
$12.17
$4.59
$8,216.28
$1,186.25
$5,258.00
"X
$15.07
'.". ' ". y '
$765.98
$125.83
$8,275.00
Quantity
2
3
8,000
2
2
2,000
' .' ;:-. ".-.: . ' .; "-* -V /
200
200
200
80
400
1
1
2
504
8
8
1
Subtotal1
$30,190.44
$13,956.51
$446,960.00
$37,100.50
$550.00
$34,180.00
:': " . '- "';'" "
$158.00
$208.00
$466.00
$973.60
$1,836.00
$8,216.28
$1,186.25
$10,516.00
$7,595.28
1 : (.-- >. .'-. >-.
$6,127.84
$1,006.64
$8,275.00
Activity Total*
$2,905,900.51
$31,155.41
$15,409.48
80
-------
TABLE 5 (Continued)
COST ESTIMATE FOR THE SELECTED REMEDY
ircxripuoD
Unit j CcsfUaJf Qasssilty Sublets!1 | Activity Teta!*
Cleanup and Landscaping
Site Restoration
24 ft x 1 0 in Concrete Access
Roadway
24-ft Gravel Access Roadway
24-in Deep Clay Cap
6-in Deep Topsoil
AC
SY
LF
CY
CY
$2,682.26
$30.57
$18.40
$18.00
$22.00
17.50
550.00
2,000.00
51,145.49
8,439.01
$46,950.15
$16,813.50
$36,800.00
$920,618.91
$185,658.15
Subtotal $1,206,840.71
Treatment Costs
Unit Mobilization
Unit Demobilization
Verification Sampling
Trial Bum
LS
LS
LS
LS
$150,000.00
$75,000.00
$400,000.00
$250,000.00
1
I
1
1
$150,000.00
$75,000.00
$400,000.00
$250,000.00
Subtotal $875,000.00
Surface to 1 Foot bgs
Perimeter Excavation
Area Excavation
Treatment Costs
Backfill Treated Material
CY
CY
Ton
CY
$11.70
$11.70
$36.50
$2.93
89.44
33,244.57
50,001.02
33,334.01
$1,046.48
$388,961.49
$1,825,037.27
$97,668.66
Subtotal $2,312,713.89
1 Foot to 2 Feet bgs :~; " ,:
Perimeter Excavation
Area Excavation
Treatment Costs
Backfill Treated Material
CY
CY
Ton
CY
$11.70
$11.70
$36.50
$2.93
92.55
27,765.32
41,786.80
27,857.87
$1,082.81
$324,854.24
$1,525,218.25
$81,623.55
Subtotal $1,932,778.85
2to4Feetbgs f? f V
Perimeter Excavation
Area Excavation
CY
CY
$11.70
$11.70
70.58
7,623.98
$825.77
$89,200.54
81
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TABLE 5 (Continued)
COST ESTIMATE FOR THE SELECTED REMEDY
Description
Treatment Costs
Backfill Treated Material
Installation of Geotextile
Unit
Ton
CY
SF
Cost/Unit"
$36.50
$2.93
$0.85
Quantity
11,541.83
7,694.56
158,344.15
Subtotal1
$421,276.96
$22,545.05
$134,592.53
Subtotal $668,440.84
Off-Site Areas ' - " - - -~~-:- - = - . -
Excavation (1,390 ft North Stream,
4,160 ft South Stream, 1,000 ft
North Ditch)
Treatment Costs
Stream Dewatering
Imported Backfill and Placement
CY
Ton
LF
CY
$11.70
$36.50
$25.00
$18.00
5,540.60
8,310.90
5,550.00
5,540.60
$64,825.02
$303,347.85
$138,750.00
$99,730.80
Subtotal $606,653.67
Activity Total*
Activity Subtotal $6,395,587.26
Project Cost Subtotal $13,516,962.50
Contingency (5%)
Contractor Overhead (6%)
Contractor Profit (7%)
Annual Water Well Sampling (3%
Inflation, 4% Discount)
Recovery System O&M
(3%Inflation, 4% Discount)
Cap Maintenance (3% Inflation, 4%
Discount)
Local Road Reconstruction
Following Project Completion
%
%
%
LS
LS
LS
Mile
-
--
$293,875.00
$866,497.06
$115,659.30
$250,000.00
5
6
7
1
1
1
5
$675,848.12
$811,017.75
$946,187.37
$293,875.00
$866,497.06
$115,659.30
$1,250,000.00
$675,848.12
$811,017.75
$946,187.37
$293,875.00
$866,497.06
$115,659.30
SU 50,000.00
Project Total Present Cost $18,476,047.1 1
82
-------
TABLE 5 (Continued)
COST ESTIMATE FOR THE SELECTED REMEDY
Table 5 Nuics:
AC Acre
bgs Below ground surface
CAT Caterpillar bulldozer
CY Cubic yard
gpd Gallons per day
gpm Gallons per minute
HP Horsepower
HR Hour
LF Linear foot
LS Lump sum
MNTH Month
MWK Man-week
O&M Operation and Maintenance
P&A Plugged and abandoned
psi Pounds per square inch
PVC Polyvinyl chloride
SY Square yard
83
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REASONS OTHER ALTERNATIVES WERE NOT SELECTED
A summary of the major reasoning for not choosing the other alternatives is as follows:
1. Alternative 1 -No Further Action:
Not protective of human health and the environment.
2. Alternative 2-Institutional Controls / Ground Water Monitoring:
Long term risks remain and may actually increase due to possible migration of
contaminants from On-site areas to Off-site areas; and,
No reduction of toxicity, mobility, or volume of principal threat wastes.
3. Alternative 3-Low Temperature Thermal Desorption & DNAPL Recovery Trench System:
USEPA's preferred alternative and selected cleanup remedy;
4. Alternative 4-Incineration & DNAPL Recovery Trench System:
The environmental benefit compared to selected cleanup remedy does not justify the
significant cost difference.
5. Alternative 5-Solidification/Stabilization & DNAPL Recovery Trench System:
Does not reduce volume of contaminants; and,
Implementation would increase volume of contaminated soil by 25 to 30 percent in order
to immobilize contaminants.
6. Alternative 6-Capping & DNAPL Recovery Trench:
No reduction of volume or toxicity of principal threat wastes.
7. Alternative 7-Landfill Disposal & DNAPL Recovery Trench System
No reduction of mobility, volume, or toxicity of principal threat wastes; and,
Not cost effective since the environmental benefit compared to selected cleanup remedy
does not justify the significant cost difference.
84
-------
RESPONSIVENESS SUMMARY
The St. Tammany Police Jury, by Resolution Police Jury Series No. 98-8594, unanimously
support the USEPA's Proposed Plan of action for cleanup at the MCW Site. This resolution was
adopted on March 19, 1998, and sent to USEPA and Louisiana legislative delegates including:
Representative Bob Livingston, Senator John Breaux, and Senator Mary Landrieu.
The majority of public comments convey overwhelming support for the USEPA's preferred
alternative as presented in the Proposed Plan. Other public comments and questions received
during March to April 1998, along with USEPA responses, are summarized below:
STAKEHOLDER ISSUES AND USEPA RESPONSES
1) Will we get a clean bill of health after cleanup of the land?
Yes, the USEPA will give all property owners of remediated properties who request one, a
letter which states the cleanup actions that were taken will ensure the property meets the
environmental objectives established in this ROD.
2) How is the remedy going to be implemented? For example: how is the DNAPL Recovery
Trench System going to be installed?
All the specifications and plans of implementation for the LTTD technology, DNAPL
Recovery Trench System, institutional controls, and ground water monitoring will be
completed in the RD phase.
3) What if there is new contamination found?
The volumes presented in this ROD are estimates of the extent of contamination based on the
RI and FS. If additional contamination is found and this discovery results in the non-
compliance of the RAOs, then the contamination will be addressed to ensure completeness of
the remedy. If the additional contamination is a significant increase to the volume estimate
(e.g. 50% increase), then an Explanation of Significant Differences document will be
prepared to provide the public with a description of the nature of the changes made to the
remedy.
85
-------
4) Will the cleanup activities disturb any of the natural surroundings? And if so, will these
natural surroundings be restored?
Cleanup activities may disturb some of the natural surroundings in the Off-site areas of the
MCW Site. However, USEPA is taking every measure to design the cleanup remedy such
that there will only be minimal disturbances to natural habitat. All affected natural
surroundings will be replaced to the maximum extent possible.
5) What is the time frame for the completion of the LTTD activity? What will this cleanup
component consist of?
The LTTD activity is estimated to be completed after one year from its field setup date. The
LTTD activity will consist of an thermal treatment technology operation, along with all the
construction and excavation activities associated with that remedy component. Specific plans
for its design and operation will be developed within the RD phase.
6) Will the DNAPL Recovery Trench System be a permanent structure? How long will this
trench system be operated?
The DNAPL Recovery Trench System will be a permanent structure located beneath the
MCW Site. In serving as a containment and recovery system for the low teachability
creosote contaminants within the saturated zones underneath the Site, the system will be
operated until USEPA determines that the RAO for ground water has been met. This
determination will be based on operational data of this system and ground water monitoring
results.
7) Will my kids be safe to play at or near the Site? Can people live at the Site after the cleanup?
Following completion of the selected cleanup remedy, the Site will pose no health threats to
children. USEPA has formulated, using conservative assumptions, cleanup action levels
based on established risk standards to ensure the Site would be usable for residential and/or
recreational purposes in the future.
However, practically speaking, due to the long term nature of the operation of the DNAPL
Recovery Trench System, USEPA discourages future residential development in the On-site
area. Construction of recreational facilities, such as a park or a baseball diamond, are fully
acceptable.
86
-------
8) What about the use of bioremediation?
USEPA has evaluated the use of bioremediation as one of its preliminary potential cleanup
alternatives. Bioremediation was not chosen for further study since this technology could not
achieve the cleanup levels, especially for principal threat wastes within the On-site soils, at
the MCW Site.
9) Will we be able to go to the Site and observe the cleanup activities? Can we get copies of
data reports from these cleanup activities?
USEPA will work with all interested parties to schedule MCW Site tours in the most efficient
way while cleanup activities are underway. Copies of the remedial cleanup and associated
monitoring reports will be placed in the Site repositories for public information.
10) What if components of the cleanup remedy do not work or achieve the Site RAOs?
If a component of the cleanup remedy does not work during the RA, and therefore results in
the Site RAOs not being achieved, USEPA will re-evaluate its cleanup options and/or
supplement its existing cleanup components with contingency measures such that the Site
RAOs be reached.
USEPA is also directed by the NCP, since DNAPL will be present in the saturated zone
beneath the On-site area after the treatment of soil and sediment contamination, to conduct a
remedy review every five years to ensure that cleanup measures are functioning as expected.
If at any time, USEPA suspects or determines a remedy failure, in part or whole, USEPA will
again re-evaluate cleanup options and corrective action will be taken.
87
-------
APPENDIX:
SITE ADMINISTRATIVE RECORD INCLUDING COMMUNITY
AND STATE ACCEPTANCE LETTERS
10675?
-------
State of Louisiana
Department of Environmental Quality
M.J. "MIKE- FOSTER, JR.
GOVHRNOR
July 13, 1998
Mr. Stephen L. Tzhone
Remedial Project Manager
Madisonville Creosote Works Superfund Site
United States Environmental Protection Agency
Region 6
1445 Ross Avenue, Suite 1200
Dallas, Texas 75202-2733
J. DAI.I: GIVENS
SECRETARY
to
r^ o& _
> c_ ^3
c
en
m
o
RE. REVIEW OF THE DRAFT RECORD OF DECISION DOCUMENT FOR THE
MADISONVILLE CREOSOTE WORKS SUPERFUND SITE, EPA ID 981522998
Dear Mr. Tzhone:
The staff of the Louisiana Department of Environmental Quality Inactive and Abandoned Sites
Division (LDEQ-IASD) has reviewed the draft Record of Decision (ROD) document for the
Madisonville Creosote Works Supertund Site. Based upon this review the IASD supports the
draft ROD in its present form.
If you require additional information, please feel free to contact Mr. Charles Hunter at (504) 765-
0487.
Sincerely,
Administrate
GAM/CMH
'E'Cycied paper
OFFICE OF WASTE SERVICES INACTIVE AND ABANDONED S1TF.' DIVISION I* O BOX 82178 RATON ROPO ' oriSIANA 70X84.:i7S
TELEPHONE (504) ?('.f)487 FAX 15(14)'M-CMSt
AN EOWALOPFl'-RTl'MTY FVPLOYIIR
-------
Steve Stefancik
Pratldant
Floyd O.QIaM. Dlat. 1
Ray -Bamia' WWa, Jr.. Dtit. 2
Jam** A. "Red* Thompson. Dial. 3
Wl Griffin. Dtat. 4
Karry Haiwal. Sr.. OUt. 6
Gary Shgtotary. Dtot. 0
Comta Olockn«r, Dtot. 7
ST. TAMMANY PARISH PQ
P. O. BOX 628
COVINGTON. LOUISIA
(504) 898-2362 or (5
Environmental Protection Agency
1445 Ross Avenue, Suite 1200
Dallas, Texas 75202-2733
Gentlemen:
Floyd D. Glass
Vica-prasMant
D.L. 'Dawa* Ooharty. Dtet. 8
Barry Bagan. Dbt. 9
Bart Papparman. Otot. 10
Stava Stafandk. DUl. 11
Kavin Davta. Otot. 12
Joa 'Coach* Thomaa. Otot. 13
Thomas J. Snttth. Jr.. Dbt. 14
Re: Resolution P.J.S. No. 98-8594
Enclosed please find a certified copy of the above referenced Resolution regarding the proposed plan
for the Madisonville Creosote Works Superfund Site.
The St. Tammany Parish Police Jury fully supports this plan of action and, by copy of diis letter, is
requesting our legislative delegates to take whatever action is necessary to expedite this project.
Please advise if there is any assistance required from this governing body.
Very truly yours,
FLO
ST. TAMMANY PARISH POLICE JURY
VICE-PRESIDENT/DISTRICT 1 JUROR
enclosure
cc: Representative Bob Livingston
Senator John Breaux
Senator Mary Landrieu
10676
-------
ST. TAMMANY PARISH POLICE JURY
RESOLUTION
RESOLUTION POLICE JURY SERIES NO. 98-8594
A RESOLUTION TO SUPPORT THE ENVIRONMENTAL PROTECTION
AGENCY'S PROPOSED PLAN OF ACTION FOR CLEANUP AT THE
MADISONVILLE CREOSOTE WORKS SUPERFUND SITE.
WHEREAS, the Madisonville Creosote Works consists of a former wood treating facility
located adjacent to the southern side of Louisiana State Highway 22, and
WHEREAS, the wood preserving operations began in 1957 and during it's operations the
site facility treated telephone poles, railroad ties, and lumber by impregnating the wood with
creosote, and some of the compounds within the creosote mixture are carcinogenic and very
harmful to human health, and
WHEREAS, recently large tracts within one mile of the Madisonville Creosote Works
Superfund Site were rezoned for suburban use, and
WHEREAS, anticipating that a reasonable future land use for this Superfund Site will be
residential and/or recreational, the United States Environmental Protection Agency proposed
remedy will ensure all areas of the Madisonville Creosote Works will be cleaned up to
residential/recreational health standards.
NOW, THEREFORE, BE IT RESOLVED, the St. Tammany Parish Police Jury supports
the Environmental Protection Agency's proposed plan of action for cleanup at the Madisonville
Creosote Works Superfund Site.
THIS RESOLUTION HAVING BEEN SUBMITTED TO A VOTE, THE VOTE THEREON
WAS AS FOLLOWS:
MOVED FOR ADOPTION BY: GLASS, SECONDED BY: WLUL A VOTE THEREON
RESULTED IN THE FOLLOWING:
YEAS: GLASS, WILLIE, THOMPSON, GRIFFIN, HARWELL, SINGLETARY,
GLOCKNER, DOHERTY, BAGERT. PEPPERMAN. STEFANCIK, DAVIS,
AND SMITH
NAYS: 0
ABSTAIN: 0
ABSENT: THOMAS
AND THIS RESOLUTION WAS DECLARED DULY ADOPTED ON THE 19TH DAY OF
MARCH. 1998, AT A REGULAR MEETING OF THE POLICE JURY, A QUORUM OF THE
MEMBERS BEING PRESENT.
STEVE STEFANCIK, PRESIDENT
ATTEST. ST. TAMMANY PARISH POL1CEJORY
DIANE HUESCHEN, SECRETARY
ST TAMMANY PARISH POLICE JURY
"CERTIFIED COPY
OF ORIGINAL"
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