PB98-963104
EPA 541-R98-033
September 1998
EPA Superfund
Record of Decision Amendment:
J H Baxter & Company
Weed, CA
3/27/1998
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AMENDMENT #1
to the
RECORD OF DECISION
for the
J. H. BAXTER SUPERFUND SITE
WEED, CALIFORNIA
U. S. Environmental Protection Agency
Region 9
San Francisco, California
March 27, 1998
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TABLE OF CONTENTS
I. DECLARATION 1-1
II. DECISION SUMMARY IM
1.0 SITE NAME, LOCATION AND DESCRIPTION IM
1.1 Summary of Geology and Hydrogeology II-l
1.2 Historical Sources of Contamination n-2
1.3 Pre-1990 ROD Investigations D-4
1.4 Summary of 1990 ROD n-4
1.5 Post-1990 ROD Investigations and New Site Information since 1990 ROD D-5
2.0 SUMMARY OF SITE CHARACTERISTICS II-7
2.1 Nature and Extent of Contamination H-7
2.1.1 Groundwater II-7
2.1.2 Soil n-8
2.2 Soil Stratigraphy and Contaminant Migration II-9
2.3 Primary and Secondary Contaminants of Concern II-l 1
3.0 SUMMARY OF SITE RISKS 11-12
3.1 Health Risks 11-12
3.2 Environmental Risks n-14
3.3 Conclusion H-14
4.0 ENFORCEMENT ACTIVITIES IMS
4.1 1990 ROD Standards 11-15
4.2 1990 ROD Remediation Requirements and Remedial Design 11-15
4.3 1990 ROD Remedy Implementation Status for Components within the
DNAPLZone H-16
4.3.1 Subsurface Soils in the DNAPL Zone 11-16
4.3.2 Ground Water 11-16
4.4 Discharge Standards for Beaughton Creek 11-17
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TABLE OF CONTENTS (CONT)
5.0 COMMUNITY PARTICIPATION IMS
6.0 SCOPE AND ROLE OF DECISION IM9
6.1 Summary of 1990 ROD Remedy 11-19
6.1.1 Ground Water Remedy 0-19
6.1.2 Soils Remedy 0-20
6.2 ROD Amendment 0-21
7.0 DESCRIPTION OF ALTERNATIVES FOR THE DNAPL ZONE 11-23
7.1 Alternative 1 - No Further Action 11-23
7.2 Alternative 2 - Excavation to Ground Water Table After Slurry Wall
Dewatering, Ex-Situ Biotreatment, Stabilization, and On-site Disposal of
Treated Soils 0-24
7.3 Alternative 3 - Additional Containment and Institutional Controls 0-24
8.0 SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES 11-26
8.1 Comparative NCP Critera Analyses of Alternatives for the DNAPL Zone 0-26
8.1.1 Overall Protection of Human Health and the Environment fl-26
8.1.2 Compliance With ARARs 0-28
8.1.3 Long-Term Effectiveness and Permanence 0-28
8.1.4 Reduction of Toxicity, Mobility, or Volume through Treatment 0-30
8.1.5 Short-Term Effectiveness 0-31
8.1.6Implementability 0-32
8.1.7 Cost 0-34
8.1.8 State Acceptance 0-35
8.1.9 Community Acceptance 0-35
8.2 Overall Ranking of Alternatives for the DNAPL Zone 0-35
8.3 NCP criteria Analyses for Additional Remedy Modifications 0-35
8.3.1 Modification for Disposal of Treated Water 0-35
8.3.2 Surface Soils Containing Inorganic Concentrations above Background
and below the 1990 ROD Subsurface Soil Excavation Standard 0-36
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TABLE OF CONTENTS (CON'T)
8.3.3 Modification of Procedure to Verify Attainment of Soils Treatment
Standard 11-37
8.3.4 Modification of Biotreatment Implementation 11-37
8.3.5 Alternative Treatment and Disposal Options for Area B Soils 11-38
8.3.6 Modified Excavation Standards for Subsurface Soils Contaminated
withOrganics D-38
8.3.7 RCRA-Equivalent Disposal Cell. Soil Staging and Fixation Area, and
Slurry Wall Construction Zone 11-39
8.3.8 Institutional Controls E-43
8.3.9 Ditch Sediments IW3
9.0 SELECTED REMEDY 11-45
9.1 Cleanup Standards for the DNAPL Zone E-45
9.2 Selected Remedial Action for the DNAPL Zone D-45
9.3 Selected Remedy Enhancements D-47
9.4 Selection of Institutional Controls n-49
9.5 Modification of Remedy for Ditch Sediments D-49
10.0 STATUTORY DETERMINATION 11-50
10.1 Protection of Human Health and the Environment 11-50
10.2 Compliance with ARARs 11-50
10.3 Cost Effectiveness 11-55
10.4 Utilization of Permanent Solutions and Alternative Treatment Technologies
to the Maximum Extent Practicable n-57
10.5 Preference for Treatment as a Principal Element 11-57
11.0 DOCUMENTATION OF SIGNIFICANT CHANGES 11-58
12.0 REFERENCES 11-59
III. RESPONSE SUMMARY III-l
1.0 INTRODUCTION III-l
2.0 SUMMARY OF COMMENTS AND AGENCY RESPONSES III-l
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TABLE OF CONTENTS (CON'T)
TABLES
Table
1 -1 Pre-1990 ROD Contaminant Concentration Ranges
4-1 Excavation and Treatment Standards in the 1990 ROD
4-2 Excavation and Treatment Standards in the ROD as Modified by the ROD
Amendment
6-1 Selected Remedies for All Media Components at the J. H. Baxter Superfund Site
8-1 Comparison of Remedial Alternatives
8-2 Federal Applicable or Relevant and Appropriate Requirements J. H. Baxter
Superfund Site 1990 ROD
8-3 California Applicable or Relevant and Appropriate Requirements J. H. Baxter
Superfund Site 1990 ROD
8-4 Federal and State Applicable or Relevant and Appropriate Requirements for J.H.
Baxter ROD Amendment
8-5 Comparative Costs of Alternatives ($ 1,000)
8-6 Nine Criteria Analysis for the Soil Cover Modification for Surface Soils
Containing Inorganic Concentrations Above Background and Below the 1990
ROD Subsurface Soil Excavation Standard
8-7 Nine Criteria Analysis for Modification of Procedure to Verify Attainment of the
Soils Treatment Standard for Soils Placed in the RCRA-Equivalent Disposal Cell
8-8 Nine Criteria Analysis for Modification of Biotreatment Implementation
8-9 Nine Criteria Analysis for Alternative Treatment and Disposal Options for Area B
Soils
8-10 Seven Criteria Analysis for Designation of the RCRA-equivalent Disposal Cell,
the Slurry Wall Construction Zone, and the Soil Staging and Fixation Area as
RCRA Corrective Action Management Units (CAMUs)
8-11 Design, Operation, Closure and Post-closure Requirements for RCRA-equivalent
Disposal Cell
8-12 Design, Operation, Closure and Post-closure Requirements for the Soil Staging
and Fixation Area CAMU
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TABLE OF CONTENTS (CON'T)
FIGURES
Figure
1-1 Site Location Map
1 -2 Facility Plan and Target Area
1 -3 Historic Sources
2-1 Extent of Unsaturated Subsurface Soil Exceeding the ROD Requirements in
the Target Area
2-2 DNAPL Extent Map
3-1 Delineation of Soil Excavation Units
8-1 Location of Remedy Components
8-2 CAMU Locations
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TABLE OF CONTENTS (CON'T)
ACRONYMS
ARAR - Applicable or Relevant and Appropriate Requirement
ATSDR - Agency for Toxic Substances and Disease Registry
bgs - below ground surface
C&TS - Characterization and Treatability Study
CAMU - Corrective Action Management Unit
CCR - California Code of Regulations
CERCLA - Comprehensive Environmental Response, Compensation, and Liability
Act
COC - Contaminants of Concern
DHS - California Department of Health Services
DNAPL - Dense Non-Aqueous Phase Liquids
DTSC - California Environmental Protection Agency Department of Toxic
Substances Control
EPA - U.S. Environmental Protection Agency
EPCM - Engineering, Procurement and Construction Management
FFS - Focused Feasibility Study and Evaluation of Technical Impracticability
FS - Feasibility Study
GWRDI - Ground Water Remedial Design Investigation
IP - International Paper Company
LDR - Land Disposal Restriction
MCL - Maximum Contaminant Level
NCP - National Oil and Hazardous Substances Pollution Contingency Plan
NCRWQCB - North Coast Regional Water Quality Control Board
ND - below detection limit (not detected)
NPDES - National Pollutant Discharge Elimination System
NPL - National Priorities List
O&M - operating and maintenance
OCA - Older Clastic Assemblage
PAH - polycyclic aromatic hydrocarbon
PCP - pentachlorophenol
ppb - part(s) per million
PPE - personal protective equipment
ppm - part(s) per million
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TABLE OF CONTENTS (CONT)
PRO
PRP
PSA
QA/QC
RAO
RCRA
RD
RDR
RD/RA
RI
RI/FS
ROD
RWQCB
SARA
SOW
STLC
TBC
TCLP
TI
TTLC
UAO
WDR
WET
WRG
YCA
ACRONYMS
(Continued)
preliminary remediation goal
Potentially Responsible Party
Pre-Shastina Alluvial Assemblage
quality assurance/quality control
Remedial Action Objectives
Resource Conservation and Recovery Act
Remedial Design
Remedial Design Report
Remedial Design/Remedial Action
Remedial Investigation
Remedial Investigation/Feasibility Study
Record of Decision
Regional Water Quality Control Board
Superfund Amendments and Reauthorization Act
Scope of Work
soluble threshold limit concentrations
To Be Considered
Toxicity Characteristic Leachate Procedure
Technical Impracticability
total threshold limit concentration
Unilateral Administrative Order
Waste Discharge Requirement
Waste Extraction Test
Weed Remediation Group
Younger Clastic Assemblage
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I. DECLARATION
SITE NAME AND LOCATION
J.H. Baxter Superfund Site
Weed, California
STATEMENT OF BASIS AND PURPOSE
This decision document presents the U.S. Environmental Protection Agency's (EPA)
revised selected remedial actions for certain contaminated soils and groundwater at the J.H.
Baxter Superfund Site in Weed, California, which were chosen in accordance with the
Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), as
amended by the Superfund Amendments and Reauthorization Act (SARA), and to the
extent practicable, the National Oil and Hazardous Substances Pollution Contingency Plan
(NCP). This decision is based on the administrative record for this site.
The State of California concurs with the selected remedy.
ASSESSMENT OF THE SITE
Actual or threatened releases of hazardous substances from this site, if not addressed by
implementing the response action selected in the Record of Decision (ROD), as modified by
this ROD Amendment, may present an imminent and substantial endangerment to public
health, welfare, or the environment.
DESCRIPTION OF THE REMEDY
This ROD Amendment modifies the previously selected remedy for contaminated
groundwater and soils at the J.H. Baxter Superfund Site.
Studies undertaken under EPA's direction to design the remedies selected in the 1990 ROD
resulted in a significant increase in the understanding and in the estimated volume of Dense
Non-Aqueous Phase Liquids (DNAPLs) in soil at the Site. These increases, together with
questions concerning the potential effectiveness of the chosen remedy for the DNAPL-
impacted area, caused EPA to undertake the Final Focused Feasibility Study and Evaluation
of Technical Impracticability (FFS) (Bechtel 1997). On the basis of the FFS analysis, EPA
concluded that it is not possible to achieve the 1990 ROD cleanup standards for
groundwater within the DNAPL zone. For this reason, this area of the Site is also referred
to as the Technical Impracticability (TT) zone for groundwater cleanup. This ROD
Amendment documents a waiver of the ground water cleanup standards set forth in the
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1990 ROD, based on the conclusion that it is technically impracticable from an engineering
perspective (TI), to achieve these ground water cleanup standards for the DNAPL zone.
The factual basis for proposing a TI waiver of the ground water cleanup standards is set
forth in the TI Evaluation Summary in the FFS.
The remedy consists of the 1990 ROD components plus enhancements, modifications, and
additional containment measures as described in this amendment Actions have also been
selected to modify other aspects of the soils remedy previously selected for the site in the
1990 ROD. The major components of the selected remedy include the following:
Slurry Wall
• Enhancement of the groundwater remedy described in the 1990 ROD by
constructing a slurry wall around the DNAPL zone. The slurry wall is a physical
barrier that would prevent further contamination and facilitate faster cleanup of the
groundwater outside of the DNAPL zone. The slurry wall was added as a remedial
design element to enhance the restoration of groundwater outside of the DNAPL
zone. The remedy, without a slurry wall, will not be protective of human health and
the environment Groundwater outside of the DNAPL zone will be restored by
pumping and treatment as provided for by the 1990 ROD.
• Cleanup of contaminated surface soils, whether inside or outside of the DNAPL
zone, and contaminated subsurface soils (deeper than two feet) outside of the
DNAPL zone in accordance with the ROD, with certain modifications. Subsurface
soils within the DNAPL zone will not be excavated.
Additional Containment and Institutional Controls within the DNAPL Zone
• Regrading and covering of the open excavation on the Roseburg property (Roseburg
excavation) which acts as a collection point for contaminated surface runoff. The
excavation would be covered with a minimum of two feet of clean soil. These
measures would improve surface drainage, reduce contamination of surface water
runoff, and reduce the potential for worker exposure to contaminated soils.
• Collection and treatment of liquids from DNAPL seeps in the Roseburg excavation.
• Implementing institutional controls to prevent exposure to waste left in the DNAPL
zone. These controls would include 1) limiting future land uses to appropriate
industrial uses; 2) restricting access to and use of contaminated groundwater; 3)
prohibiting activities that would disturb the integrity of the remedy including
appropriate prohibitions on activities that would disturb the soil and/or any cap
placed upon such soil; 4) requiring appropriate handling of excavated materials; 5)
providing for appropriate notice that hazardous wastes remain on site; and 6)
prohibiting other activities which could cause a potential threat to human health or
the environment.
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Modification for Disposal of Treated Water
• Addition of the option of direct discharge to Beaughton Creek for treated water
based on NCRWQCB regulatory actions to require treatment of water to best
practicable methods. The preferred disposal option continues to be reuse on
Roseburg's log decks as described in the 1990 ROD. Reuse on the log decks would
reduce water diversions from Beaughton Creek, which is water-limited during the
dry season.
Additional Modifications to Soils Remedies
• Surface Soils Containing Inorganic Concentrations above Background and below
the 1990 ROD Subsurface Soil Excavation Standard - Covering these soils with a
protective asphaltic concrete surface, rather than excavating and reburying the soils
on-site at a depth greater than two feet This modification will provide equal long-
term protectiveness while minimizing short-term risks associated with excavation
and handling of soils.
" Modification of Procedure to Verify Attainment of Soils Treatment Standard -
Modifying the 1990 ROD leachate test for soils to be placed in a lined disposal cell
(equivalent to Resource Conservation and Recovery Act [RCRA] disposal cells).
The new test will use deionized water rather than a citric acid buffer for the leaching
solution. The test will be used to demonstrate that soils have met the numerical
limits selected in the 1990 ROD. Because testing has shown that Site soils are not
acidic, deionized water, which is neutral, may be more representative of Site
conditions. Additionally, as this modification will apply only to soils to be placed in
the RCRA-equivalent disposal cell, there is no increased threat to humans or
groundwater.
• Modification of Biotreatment Implementation - Broadening the implementation
options for biotreatment to allow treatment in place (in situ), with appropriate
monitoring and controls. However, all bio treated soils (with possible exception of
Area B soils as explained below) will be excavated and placed in a lined RCRA-
equivalent disposal cell.
• Alternative Treatment and Disposal Options for Area B Soils - Area B soils are
contaminated with organics and are believed to have been excavated from the
DNAPL zone and moved to their current location when Roseburg began
preparations for new building construction. EPA has selected treatment standards
for Area B based on groundwater protection concerns. In addition, all Area B
surface soils will be covered by two feet of clean soil. EPA will evaluate in situ
bioventing as the treatment technology for Area B soils. EPA and will also evaluate
the results of modeling and/or other studies to assess the impact of contaminated
soils on groundwater in order ensure that the cleanup levels achieved by bioventing
will be protective of groundwater. If EPA concludes that the cleanup levels
achieved by bioventing will be protective of groundwaier, then Area B soils will
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remain in place after treatment has been completed. If EPA concludes that the
cleanup levels achieved by bioventing will not be protective of groundwater, then
the remedy will be biotreatment and subsequent disposal in a RCRA-equivalent
disposal cell. Area B soils to be placed in the RCRA-equivalent cell must comply
with the 1990 ROD treatment standards using the modified leachate test described
above.
Modified Excavation Standards for Subsurface Soils Contaminated with Organics -
EPA has modified the 1990 ROD subsurface soil excavation standards for
organics-contaminated soils outside the DNAPL zone in order to ensure that they
remain protective of groundwater. The new subsurface soil excavation standards
are the same as the Area B treatment standards and will apply to all soils located
outside the DNAPL zone which are contaminated with organics (including Area B
soils, if bioventing is not successful and the soils are ultimately excavated). As with
Area B, EPA will evaluate the results of modeling and/or other studies to assess the
impact of contaminated soils on groundwater. In accordance with the remedy
modifications described above, subsurface soils within the DNAPL zone will not be
excavated. Excavated soils to be placed in the RCRA-equivalent disposal cell must
comply with the 1990 ROD treatment standards using the modified leachate test
described above.
Designation of Corrective Action Management Units - EPA has designated three
features of the remedy as RCRA Corrective Action Management Units (CAMUs):
the RCRA-equivalent disposal cell, the soil staging and fixation area, and the slurry
wall construction zone. All soils that have been excavated and treated and all soils
that have undergone in situ biotreatment (other than successful bioventing) will be
disposed of in a RCRA-equivalent disposal cell that complies with the RCRA
landfill requirements, including groundwater monitoring, leachate control, and
closure requirements. Neither placement of remediation wastes into the RCRA-
equivalent cell, nor temporary placement of soils in the soil staging and fixation area
or slurry wall construction zone, nor incorporation of contaminated soils into the
slurry wall trench will constitute land disposal of hazardous wastes because EPA
has designated each of these areas as a CAMU.
Modification for Handling of Contaminated Soils Uncovered during Operation
and Maintenance
Handling of Soils during Operation and Maintenance - A soils handling plan will be
developed and approved by EPA to address instances where building
decommissioning/construction activities, routine maintenance, or other ground
intrusive activities on site may occur.
Modification for Ditch Sediments
Revised Remedy for Ditch Sediments - The requirements for excavation, treatment,
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and disposal of contaminated sediments within drainage ditches discharging Site
runoff into Beaughton Creek is modified in light of the fact that natural flushing and
attenuation are reducing the concentrations of contaminants. The ditch sediments
will be allowed to continue to degrade naturally to the standards specified in the
ROD. However, stream sediments will continue to be monitored and the areas of
concern in the stream will be posted with cautionary signs. In addition, the
discharge and surface water runoff from the site will continue to be monitored to
ensure protectiveness.
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, and is
cost-effective. This remedy utilizes permanent solutions and alternative treatment
technologies to the maximum extent practicable for this site. The revised soil and
groundwater remedies utilize both containment and treatment technologies to reduce
toxicity, mobility, or volume of contaminants. However, because treatment of the DNAPLs
in the TI zone was not found to be practicable, this remedy does not satisfy the statutory
preference for treatment as a principle element of the remedy for groundwater and
subsurface soils in the DNAPL zone.
Because the remedies will result in hazardous substances remaining on-site above health-
based levels, EPA will conduct a review pursuant to Section 121 (c) of CERCLA, 42 U.S.C.
§962 l(c), within five years after commencement of remedial action to insure that the
remedy continues to provide adequate protection of human health and the environment.
Date Keith Takata
Director, Superfund Division
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II. DECISION SUMMARY
1.0 SITE NAME, LOCATION AND DESCRIPTION
The J.H. Baxter Superfund site (Site) is located at the northeastern border of the city of Weed in
Siskiyou County, California (see Figure 1-1). The Site includes the property owned by J.H.
Baxter & Company (Baxter) and Roseburg Forest Products (Roseburg). Baxter operates a wood
treatment plant, and Roseburg operates a lumber mill and veneer plant. Wood treatment is
intended to protect wood from deterioration due to insects and fungi, using a variety of chemical
compounds including creosote, arsenic, chromium, copper, zinc, and pentachlorophenol. The
companies that previously have been responsible for wood treatment operations (since 1937)
include American Lumber and Treatment Company, and International Paper Company (IP). The
Potentially Responsible Parties (PRPs), as identified by the U.S. Environmental Protection
Agency (EPA), have formed the Weed Remediation Group (WRG).
The Site is bordered on the west and northwest by residential areas of Weed, to the north by the
Angel Valley Subdivision and Lincoln Park, to the east by mixed woodlands, and to the south by
irrigated pasture (Figure 1-2). Beaughton Creek runs through the eastern portion of the Site. For
a description of the regional setting, refer to Section 1.3.1 of the 1990 Feasibility Study (FS)
(SAIC 1990).
The geology and hydrogeology of the Site have been presented in several documents both prior to
and since the issuance of the 1990 FS and Record of Decision (ROD) (EPA 1990). These
include the Remedial Investigation (RI) report (CDM 1989), the Characterization and
Treatability Study Report of Results (C&TS) (Grant 1993), and the Ground Water Remedial
Design Investigation Report (GWRDI) (Grant 1995). This section summarizes the 1990 ROD,
describes in general terms what has been learned about the Site since the 1990 ROD, and briefly
summarizes the geology and hydrogeology. Stratigraphic units and aquifer characteristics are
described in detail in Section 1.2.4 of the Final Focused Feasibility Study and Evaluation of
Technical Impracticability (FFS) (Bechtel 1997).
1.1 Summary of Geology and Hvdrogeology
The RI Report defines five Stratigraphic units at the Site:
• Artificial fill
• The Younger Clastic Assemblage (YCA)
• The Pre-Shastina Alluvial Assemblage (PSA)
• The Older Clastic Assemblage (OCA)
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• Bedrock
The GWRDI reports several water-bearing zones separated by unsaturated volcanic flows. Based
on the previous work conducted at the Site, published literature, and work conducted at the Site
during the GWRDI, the following stratigraphic sequence is currently thought to occur at the Site:
• Artificial fill
• Recent Alluvium
• Shastina Pyroclastic Flow
• The PSA
• The OCA
• Older pyroclastic flow deposits
While similar to what was thought to exist at the time of the RI Report, this stratigraphic
sequence does differ in one important aspect. As described in the GWRDI Report, a distinct
competent bedrock unit defining the base of the hydrologic system has not been found within at
least several hundred feet of the surface. Therefore, a bedrock unit is not included in the current
understanding of Site stratigraphy.
There are two main aquifers at the Site. The first aquifer is referred to as the uppermost aquifer.
The second aquifer is described as the lower aquifer. The two aquifers are separated by the OCA
aquitard. Depth to ground water at the Site varies from a few feet below ground surface (bgs) to
over 20 feet bgs. Hydrographs from monitoring wells indicate that there is a persistent
downward vertical gradient across the Site between the two aquifers. The head difference can be
as much as 20 feet.
The most important unit of the subsurface at the Site is the OCA. Generally, the OCA has been
observed to act as an effective barrier to vertical contaminant migration from the upper aquifer to
the lower aquifer, as noted in the RI report, C&TS report and the GWRDI report.
1.2 Historical Sources of Contamination
Wood treatment operations at the Site were initiated in 1937. A detailed history of Site
operations was included in the original FS. Therefore, only a summary of the contamination
sources as they relate to the Dense Non-Aqueous Phase Liquid (DNAPL) zone is presented in
this section.
Waste disposal, handling, and discharge practices over more than 55 years of operation at the
Site have released wood treatment-related hazardous substances to Site soil, ground water, and
surface water. Wastes generated at the Site, consistent with those at wood treatment facilities,
include retort drippings, tank and retort sludges, process water, wastewater, drying area
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drippings, storage area drippings, empty containers, and spilled raw preservative compounds.
Source areas within the DNAPL Zone are shown in Figure 1-3, and are briefly described below.
Tank Berm Area Around the 500,000-Gallon (No 3) Tank - A 500,000-gallon tank was
installed in 1936 to store creosote. Spills of creosote from the tank have been reported
historically. The RI report also noted that no attempt was made to cleanup early spills and
creosote was allowed to seep into the ground. The tank was converted to a process-water surge
tank in 1983.
The bermed area was reported to have received water from process waste water vaults and
process water. This area was reported to have been used for disposal of sludges from storage and
process tanks. Sludges were removed from the bermed area in 1985; however, contaminated
soils remain.
Retort and Process Area - Several leaks and direct discharges of wood treatment chemicals
from the process area onto the western portion of the property have been reported from the 1940s
through 1970s. Also, an underground tank existed below the retorts, which at one time received
used treatment solutions. This underground tank was reported to have been filled with ground
water before it was closed.
Buried Pond Area - Unlined settling ponds and pits containing wood treatment salts, and dip
ponds containing creosote were reported to have been present at the north end of the wood
treatment property near the Roseburg Excavation. These ponds and pits received excess
treatment chemicals from the retorts, and were used by local residents to dip fence posts. It is
thought that these unlined ponds and pits have probably contributed to the presence of creosote
observed within the Roseburg Excavation.
Former Oil/Water Separator/Creosote Pit Area - An oil/water separator was installed at the
Baxter property in 1955 to recover creosote product. Discharges and oil spills from the unit were
reported as well as a leak in the inlet pipe. The oil/water separator was taken out of service in
1984.
During the 1960s, Baxter plant's sewage system and wastewater from the retorts drained into IP's
log ponds. To reduce this drainage, Baxter dug a pit to contain 500 cubic feet of waste, however,
overflows from the pit and oil/water separator continued to discharge into the log ponds. The pit
was closed and filled in 1981. Baxter, at a later date, also cleaned the ditch (shown as the
"Possible Discharge Ditch to Log Ponds", in Figure 1-3) that discharged to the pond, filling in the
ditch with soil and installing a culvert.
Former Waste Water Vaults - Two concrete-lined vaults were used to hold wastewater from oil
and water-based chemical solutions, condenser water, cooling water, spillage drainage, wash
water from retorts, and runoff. These wastewater vaults were used between 1975 and 1984/85,
when they were decommissioned.
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From 1975 to 1983, water entering the wastewater vaults was piped to irrigation sprinklers and
sprayed on to an open field adjacent to the southern edge of the facility. However, excess water
was reported to have been discharged into Site culverts, into the tank berm area, and directly onto
the ground surface when capacity of the spray system was exceeded.
The process of transferring wood treatment related chemicals from rail tank cars to facility
storage vessels was also reported as a source of spills at the Site. There are miscellaneous reports
of spills during unloading during the 1950s. There are also reports of leaks from failing transfer
hoses, and the loss of creosote from a tank car.
1.3 Pre-1990 ROD Investigations
Remedial investigations at the Site began in 1983 at the request of the North Coast Regional
Water Quality Control Board (NCRWQCB) and the California Department of Health Services
(DHS), now the California Environmental Protection Agency Department of Toxic Substances
Control (DTSC). Investigation results at that time indicated that Site soils, surface water runoff,
and ground water contained elevated levels of arsenic, creosote, and pentachlorophenol (PCP)
(Table 1-1). In 1984 EPA proposed that the Site be included on the National Priorities List
(NPL).
EPA initiated the RI of the Site in 1987 and released the RI report in 1989 (CDM 1989). EPA
then performed the FS (SAIC 1990) based on the RI. The 1990 FS addressed all impacted media
at the Site including surface soils, subsurface soils, ground water, surface water, and sediment.
EPA issued the ROD (EPA 1990) on September 27, 1990 based on the results of the April 27,
1990 FS. EPA then issued Unilateral Administrative Order 91-92 (UAO) with a Scope of Work
(SOW) on August 19, 1991 that detailed the remedial actions to be conducted at the Site (EPA
1991).
1.4 Summary of 1990 ROD
The 1990 ROD presents the selected remedial actions for the J.H. Baxter Superfund Site in
Weed, California, chosen in accordance with the Comprehensive Environmental Response,
Compensation, and Liability Act (CERCLA), as amended by the Superfund Amendments and
Reauthorization Act (SARA), and to the extent practicable, the National Oil and Hazardous
Substances Pollution Contingency Plan (NCP). This decision was based on the administrative
record file for this Site as of 1990. The State of California concurred with the selected remedies.
The 1990 ROD documents that actual or threatened releases of hazardous substances from this
Site, if not addressed by implementing the response actions, may present an imminent and
substantial endangerment to public health, welfare, or the environment.
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The response actions selected by the 1990 ROD address the documented principle public health
and environmental threats from the Site contamination. Actions were selected to address the
contaminated soils, groundwater, and surface water. The major components of the selected
remedy include the following:
• Extraction of the contaminated groundwater followed by biological treatment and
chemical precipitation, polishing, and disposal. The preferred disposal method for
the treated groundwater was reuse on the Roseburg log decks. Other disposal
options included: reinjection to groundwater, release to subsurface drains or
trenches, industrial process use, and/or disposal to percolation ponds. This ROD
Amendment incorporates the slurry wall as a component of the design for the
groundwater remedy in order to meet the objectives of the 1990 ROD. The slurry
wall was added to enhance the restoration of groundwater outside of the DNAPL
Zone. The remedy, without a slurry wall, will not be protective of human health
and the environment.
• Excavation of the organic contaminated soils and biological treatment in lined
treatment cells with disposal after treatment in a Resource Conservation and
Recovery Act (RCRA)-equivalent cell.
• Excavation of the inorganic soils and chemical fixation followed by on-site
disposal in lined treatment cells for treated soils designated as hazardous waste.
• Excavation of the combined organic/inorganic soils, biological treatment in
treatment cells, chemical fixation, and on-site disposal into a lined RCRA-
equivalent cell.
1.5 Post-1990 ROD Investigations and New Site Information since 1990 ROD
Since the 1990 FS was prepared and the 1990 ROD was issued, a significant amount of
additional data have been obtained through further investigation and characterization work
conducted at the Site. Under EPA's direction, the WRG undertook C&TS investigations in 1992-
1993 (Grant 1993) and the GWRDI in 1993-1994 (Grant 1995) to provide specific information
necessary to design the remedies selected by EPA in the 1990 ROD. These data have contributed
to a better understanding of the extent of contamination, especially the DNAPLs in the
subsurface.
During post-1990 ROD ground water remedial design characterization, the WRG issued the
C&TS (Grant 1993). EPA instructed the WRG to better define the extent of DNAPLs in the
saturated and unsaturated (vadose) zone soils. The WRG addressed the DNAPL extent in the
GWRDI Report issued in February 1995 (Grant 1995). The results of the studies confirmed that
creosote contamination at this Site is present in soil and groundwater and in the form of DNAPLs
above and below the groundwater table. However, the results indicated DNAPLs extend
throughout a much wider and deeper portion of the Site than was previously thought, and that
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subsurface soil contamination was also much more widespread. The studies identified two
additional areas of soils with organics contamination: the Roseburg excavation and Area B.
These reports found significant increases in the estimated volume of contaminated soil over the
1990 ROD estimate. The 1990 ROD estimated 41,000 cubic yards of contaminated soil subject
to cleanup. This total included both surface soil and subsurface soil to a depth of 12 feet bgs (the
depth of the water table). Post-1990 ROD investigations estimated 201,500 cubic yards of
impacted soil in the unsaturated zone (surface soil and subsurface soil above the water table)
(Bechtel 1997). These increases, together with questions concerning the potential effectiveness
of the chosen remedy, caused EPA to undertake the FFS for the DNAPL-impacted area.
In addition to the significant increase in the understanding of the volume and extent of DNAPLs
in the subsurface, EPA's understanding of the technical issues for remediation of DNAPL-
contaminated sites has continued to evolve since the 1990 FS (SAIC 1990) was completed.
These issues have been addressed in several publications, including a study by the National
Research Council (NRC 1994). In light of these new Site data, in response to a request from the
PRPs, i.e., WRG, and consistent with the 1995 Superfund Administrative Reforms (EPA 1995),
EPA developed the FFS (Bechtel 1997). The FFS reevaluated the remedial action alternatives for
DNAPL-impacted subsurface soils and ground water at the Site.
On the basis of the FFS analysis, EPA concluded that it is not possible to achieve the 1990 ROD
cleanup standards for groundwater within the DNAPL Zone and designated this area of the Site
as the Technical Impracticability (TI) zone for groundwater cleanup. This ROD Amendment
documents a waiver of the ground water cleanup standards set forth in the 1990 ROD, based on
the technical impracticability from an engineering perspective for the DNAPL Zone. The factual
basis for proposing a TI waiver of the ground water cleanup standards is set forth in the TI
Evaluation Summary in the FFS.
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2.0 SUMMARY OF SITE CHARACTERISTICS
Waste disposal, handling, and discharge practices over more than 50 years of plant operation
have resulted in Site soil, groundwater, surface water, and sediment contamination with a variety
of chemicals used in wood treatment operations. These include the F032, F034 and/or F035
hazardous wastes listed pursuant to 40 CFR Part 261 of the RCRA regulations (as implemented
through 22 California Code of Regulations 66261) as well as 0004, D007 and D037
characteristic hazardous waste. The F032, F034 and F035 listed wastes, which are related to
wood preserving operations, were listed after the date of the ROD. See 57 Federal Register
61492 (December 30, 1992). This ROD Amendment recognizes this new listing because EPA
has concluded that this is necessary to ensure that the remedy remains protective of human health
and the environment. Arsenic, carcinogenic polycyclic aromatic hydrocarbons (PAHs),
pentachlorophenol and dioxins are the primary contaminants of concern. Chromium, copper,
zinc, benzene and noncarcinogenic PAHs are also present at the Site.
2.1 Nature and Extent of Contamination
This section describes the current understanding of contaminant nature and extent in soils and
groundwater throughout the Site and the volume of impacted saturated and unsaturated soils
within the DNAPL Zone that will be contained by the slurry wall. This understanding is based
on data from the C&TS, (Grant 1993), the Draft Preliminary (90 percent) Soil Remedial Design
(Grant 1995a), GWRDI (Grant 1995), and the ENVIRON Report (ENVIRON 1995).
Groundwater and subsurface soils that are within the DNAPL Zone are addressed in depth in this
ROD Amendment. Surface soil both within and outside of the slurry wall and subsurface soil
outside of the slurry wall will be cleaned up in accordance with the 1990 ROD (with the
modification described in Section 8.3.2 of this ROD Amendment). Only a brief discussion of
soils is presented in this section of the ROD Amendment.
2.1.1 Groundwater
Groundwater sample results showed the presence of a creosote and arsenic plume, originating at
the Baxter wood treatment area and extending to the northwest into the Roseburg property
towards the Angel Valley subdivision (Figures 1-3 and 4-2 of the 1990 ROD). Arsenic at 1,740
parts per billion (ppb) and creosote compounds at 233,000 ppb were detected in Roseburg
monitor well RMW1, which was located immediately downgradient of the wood treatment
property and 1,600 feet upgradient of the subdivision. A portion of this arsenic and creosote
plume is being captured by the Roseburg french drain. According to the RI Report and
December 1989 monitoring data, wells downgradient of the french drain and adjacent to and
within the subdivision did not show the presence of Site contaminants.
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2.1.2 Soil
Although widespread arsenic contamination (40 to 38,500 parts per million [ppm]) is generally
limited to surface soils (to a depth of at least one foot), arsenic contamination extended deeper
(up to 5 feet) below the retort, wastewater impoundments, and tank-bermed areas of the property.
Contamination of surface soils by creosote (below detection limit [ND] to 10,384 ppm) and
pentachlorophenol (ND to 2,440 ppm) was less widespread than the inorganic contamination, but
much deeper. Organic contamination below the tank berm, retort, and wastewater vault areas
extends to at least 30 feet below ground surface. Pre-1990 ROD investigations found a
subsurface creosote body (DNAPL) of up to 15 feet in thickness under the wood treatment
property. The DNAPL extent was further characterized in the C&TS (Grant 1993) and the
GWRDI Report (Grant 1995). These reports found significant increases in the estimated volume
of contaminated soil over the 1990 ROD estimate. The 1990 ROD estimated a total volume of
contaminated soil above the water table (in the unsaturated zone) of 41,000 cubic yards divided
into the following subunits:
• Soils contaminated with inorganics only 18,750 cubic yards
• Soils contaminated with organics only 12,500 cubic yards
• Soils contaminated with organics and inorganics 9,380 cubic yards
The current understanding of contaminant extent and volume of impacted saturated and
unsaturated soils in the DNAPL Zone is based on data from the C&TS, (Grant 1993), the Draft
Prefmal (90 percent) Soil Remedial Design (Grant 1995a), GWRDI (Grant 1995), and the
ENVIRON Report (ENVIRON 1995). These sources estimated a total volume of contaminated
soil in the unsaturated zone of 201,500 cubic yards divided into the following subunits:
• Soils contaminated with inorganics only 50,500 cubic yards
• Soils contaminated with organics only 130,500 cubic yards
• Soils contaminated with organics and inorganics 20,500 cubic yards
The GWRDI estimated the portion of these contaminated unsaturated soils that are impacted by
DNAPL to be 27,000 cubic yards. The FFS assumed that these 27,000 cubic yards are included
as pan of the total extent of the unsaturated soil impacted by all contaminants of concern as
identified in Figure 2-1.
One of the objectives of the GWRDI was to determine the extent of DNAPL contamination in
the subsurface in the saturated zone as well as the unsaturated zone. The 1990 ROD did not
address contaminated soil in the saturated zone as the remedy only addressed soil above the
water table. The data the GWRDI collected were not always conclusive and they are subject to
considerable variation in interpretation. Figure 2-2 shows the various interpretations of DNAPL
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extent in the subsurface that were prepared by three different WRG consultants using nearly the
same data set.
In order to evaluate remediation alternatives for DNAPLs in the saturated zone, the FFS used
minimum and maximum volumes of impacted saturated soil of 98,000 cubic yards and 1.210,000
cubic yards, respectively. The FFS used a range of volumes derived from estimates of the
minimum and maximum possible contaminated soil because of the problems in identifying the
extent of DNAPL impacted soil in the saturated zone, the associated uncertainty in estimating its
volume, and the lack of other data.
The different depictions of DNAPL presence shown on Figure 2-2 illustrate the difficulty and
uncertainty in locating and identifying DNAPL in the subsurface. Such variations in
interpretations are not unexpected. The difficulty in locating and identifying DNAPL in the
subsurface is well recognized and is documented in numerous publications. DNAPL Site
Evaluation (Cohen and Mercer 1993), prepared for EPA's Robert S. Kerr Environmental
Research Laboratory, provides in-depth discussions regarding these and other DNAPL location
and identification issues.
2.2 Soil Stratigraphy and Contaminant Migration
Each of the stratigraphic units that are considered to occur within the DNAPL Zone is discussed
below.
Artificial Fill
Fill occurrence at the Site varies, but generally can be grouped into three categories:
• Gravely sand derived from local quarries
• Gravely sand and log debris
• Gravely sand, construction debris, and associated Site soils
Within the DNAPL Zone there is fill from nearby quarries in the Baxter property, the Roseburg
Excavation, and the French Drain. This fill typically is a gravely sand that can be difficult to
distinguish from the Shastina Pyroclastic Flow, and ranges from less than 1 foot to 18 feet thick
within the DNAPL Zone.
Recent Alluvium
Recent alluvium deposits do not occur within the DNAPL Zone.
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Shastina Pyroclastic Flow
The most dominant geologic feature in the Weed, California area is the Shastina Pyroclastic
Flow. Based on the stratigraphic description, the YCA unit noted in the RI report is roughly
equivalent to the Shastina Pyroclastic Flow. It is a poorly-sorted, unstratified pyroclastic debris
flow. It consists of a silty, gravely sand to sandy unit. Gravel is angular to subangular, and can
be greater than 2.5 inches in diameter. Locally it contains alternating beds of silty sand, sandy
silt, and rounded gravel. The transition to the underlying PSA occasionally is marked by a
sandy-silt to silty-sand layer. The Shastina Pyroclastic Flow has a distinctive pinkish-brown to
pinkish-gray color. It ranges up to 22 feet thick within the DNAPL Zone.
Pre-Shastina Alluvial Assemblage
The PSA is generally a well-sorted unit of fluvial origin. It consists of fine to medium sand to
silty sand and gravely medium coarse sand. Gravels in this unit are generally less than one inch
in diameter. Locally on the Site the PSA can be poorly sorted and very silty, which may
represent transitional environments of a fluvial system. The PSA is brown to gray and can have a
reddish or greenish hue. The PSA appears to be persistent across the DNAPL Zone and ranges
from 3 to 18 feet thick.
Older Clastic Assemblage/Aquitard Layer
The OCA is a distinctive unit that is present beneath the PSA. The OCA caps the older
pyroclastic flows and the lower aquifer. The OCA acts as the confining layer that separates the
uppermost aquifer from the lower aquifer and constitutes the lower boundary of the DNAPL
Zone. The OCA slopes downward toward the northwest end of the DNAPL Zone. In air rotary
drill cuttings, the OCA is described as a brown gravely clay. In split-spoon samples, the OCA is
described as dense greenish-gray silt or sandy silt. The boring logs indicate that the OCA ranges
in thickness from 2 feet near the southern end of the DNAPL Zone to approximately 29 feet, near
the northern end of the DNAPL Zone.
The most important unit of the subsurface within the DNAPL Zone is the OCA. The OCA has
been observed to act as an effective barrier to vertical contaminant migration from the upper
aquifer to the lower aquifer, as noted in the RI report, C&TS report and the GWRDI report.
However, the OCA in localized areas may not be effective in mitigating the downward migration
of contaminants. For example. Site contaminants have been observed at two locations in the
Lower Aquifer, at Well B-l and Well B-15. The WRG attributed the observed contamination to
faulty installation of Well B-l. However, as the extent of the contamination in the Lower
Aquifer is not delineated, additional pathways, including permeable zones within the OCA,
cannot be ruled out. As of this writing, Well B-l has been properly abandoned and a
replacement well, B-1R, has been drilled. As an interim remedial measure to address the
contamination in the Lower Aquifer, extraction of ground water from Well B-1R has been
initiated and continues to date. The WRG is evaluating the effectiveness of pumping Well B-1R
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and will propose modified plans to EPA to address the observed contamination in the lower
aquifer.
Despite the ground water impact observed in these two well locations in the lower aquifer,
current understanding at the Site is that, within most of the DNAPL Zone, the OCA appears to be
an effective barrier. Therefore, the DNAPL Zone can be considered to be bounded, at depth, by
the OCA, and does not include the Lower Aquifer or subsurface soils below the OCA.
The uppermost aquifer ground water flow direction across the Site is generally to the north-
northwest. The proposed slurry wall would isolate the uppermost aquifer ground water within
the DNAPL Zone from the remainder of the uppermost aquifer at the Site. Therefore, ground
water level and flow within the DNAPL Zone would be primarily influenced by conditions
established after the construction of the proposed slurry wall and extraction system.
2.3 Primary and Secondary Contaminants of Concern
For the Site, arsenic, carcinogenic polycyclic aromatic hydrocarbons (PAHs), PCP, and dioxins
have been identified as the primary contaminants of concern (COCs). All of these contaminants
are known or suspected carcinogens and are present in each medium at concentrations exceeding
health standards. Therefore, these contaminants are considered primary health threats.
Chromium, copper, zinc, benzene, and non-carcinogenic PAHs have been identified as secondary
contaminants of concern. These contaminants are considered to be less toxic than the primary
COCs, are not widespread, are relatively immobile, and/or do not consistently exceed health-
based standards..
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3.0 SUMMARY OF SITE RISKS
EPA prepared an Endangerment Assessment to document the potential risks associated with the
actual or threatened releases of hazardous substances from the Site. The 1990 ROD provided a
summary of the information found in this document (U. S. Environmental Protection Agency,
April 30, 1990. Endangerment Assessment. Baxter/IP/Roseburg Site. Weed. California, Volumes
1 and 2, EPA WA 205-9L74). The following paragraphs briefly summarize this information and
provide additional risk assessment results for PAH compounds and PCP for the DNAPL Zone.
3.1 Health Risks
As described in the 1990 ROD, the risk assessment identified chemicals of concern for human
receptors. The chemicals were selected primarily on the basis of the concentration detected, or
the known or suspected lexicological properties of the substance. The wood treatment inorganic
(metal) chemicals of concern include arsenic, chromium, copper, and zinc, with arsenic being
identified as a high threat contaminant. The organic chemicals of concern include carcinogenic
and non-carcinogenic PAHs, PCP, tetrachlorophenol, chlorinated dibenzo dioxins and
chlorinated dibenzo furans. Carcinogenic PAHs, PCP, and dioxins have been identified as high
threat contaminants.
The evaluation performed under the risk assessment indicated that, under current land-use
conditions, the principal exposure pathways by which human receptors could potentially be
exposed to Site contaminants within the DNAPL Zone are direct contact by workers at the Baxter
facility with contaminated soils, and inhalation of fugitive dust emissions on and off site. It is
anticipated that future land use of the site will continue to be industrial. Within the risk
assessment, the exposure point concentrations of Site chemicals were estimated using measured
concentrations or models to estimate fugitive dust emissions.
The risk assessment evaluated two main baseline (No Action) scenarios: continued use of the
property as industrial (wood treatment) and future-use development of the property as residential.
The highest current-use potential health risk due to arsenic, PAHs, and dioxin was identified as
exposure by workers at the Baxter Facility to the soil by direct contact (Plausible Maximum Case
risk of 8 x 10"2). Total maximum risk to site workers from all contaminants and pathways was
identified as 1.4 x 10"'. The maximum non-carcinogenic risks from direct contact with soil by
workers at the Baxter Facility exceeded a hazard index of 1.0. Higher health risks are associated
with future residential use of the Site (see 1990 ROD Table 6-3).
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In the Endangerment Assessment (ICF/Clement 1990) conducted as pan of the RI, the principal
exposure pathways by which human receptors could potentially be exposed to Site contaminants
were identified as:
• Direct contact with contaminated soils
• Inhalation of fugitive dust emissions
• Direct contact with surface water and sediments
• Ingestion of ground water
The ROD Amendment describes the remedy for direct contact with contaminated surface soils,
inhalation of fugitive dust emissions, and direct contact with surface water and sediments. The
remedy to remove these exposure pathways includes:
• Paving where surface soil exceeds the surface soil excavation standards (Table 4-
2) and both excavation and paving where surface soil exceeds the subsurface soil
excavation standard set forth in Table 4-2. Excavated soils to be biotreated and/or
fixed to the treatment standards identified in Table 4-2, and disposed of in an
onsite RCRA-equivalent disposal cell. Excavation will be conducted in units of
limited size to minimize the amount of exposure to contaminated soil at any one
time. Figure 3-1 shows the delineation of soil excavation units.
• In situ remediation of Area B soils. Area B surface soils will be covered by two
feet of clean soil. (If bioventing is not viable, the remedy will be biotreatment and
subsequent disposal in a RCRA-equivalent cell.)
• Natural attenuation of contaminated Beaughton Creek sediments to the standards
specified in Table 4-2. Post 1990 ROD monitoring of Beaughton Creek indicates
natural flushing and attenuation of contaminated sediments has occurred. This
natural attenuation will continue with no adverse environmental impact and will
result in the concentration of contaminants of concern dropping to below sediment
excavation standards.
• Site regrading activities to improve surface water runoff control.
After remediation of surface soils across the Site, the remaining exposure pathways for
contaminants in subsurface soils within the DNAPL Zone would be contact with subsurface soils
during future Site construction activities and ingestion of ground water. These pathways will be
addressed by the imposition of institutional controls as described in Section 7.3 of this ROD
Amendment and by the development and approval by EPA of a soils handling plan.
Contaminated groundwater outside the DNAPL Zone will be remediated in accordance with the
1990 ROD.
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3.2 Environmental Risks
As discussed in the Endangerment Assessment (ICF/Clement 1990), wildlife use of the DNAPL
Zone is expected to be limited because of industrial development. Once the remedy has been
completed, there will no longer be a potential for wildlife to be in direct contact with
contaminated surface soils.
3.3 Conclusion
Actual or threatened releases of hazardous substances from this Site, if not addressed by
implementing the response actions selected in the 1990 ROD, as modified by this ROD
Amendment, may present an imminent and substantial endangerment to public health, welfare, or
the environment. The current risk afforded by Site chemicals that have been and continue to be
released into the environment represents a total cancer risk of 1.4 x 10"' and a maximum non-
carcinogenic risk (Hazard Index) of 11.1 to current workers. If the selected remedy is not
implemented, total future Site risk to children is 6 x 10', while the total future risk to adults is
8.6 x 10"'. For known or suspected carcinogens, acceptable exposure levels are generally those
concentrations that represent an upper bound lifetime cancer risk to an individual of between 10"4
and 10"6. For systemic toxicants, acceptable exposure levels represent concentration levels to
which the human population, including sensitive subgroups, may be exposed without causing
deleterious effects. This is generally interpreted as a level which will not exceed a Hazard Index
of one.
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4.0 ENFORCEMENT ACTIVITIES
This section presents a brief summary of remedial activities. For more detailed information, see
the references cited throughout the text. Emphasis in this section is on data which impact the
DNAPL Zone obtained since EPA issued the 1990 FS and ROD. This area of the Site is also
referred to as the Technical Impracticability (TI) zone for groundwater cleanup.
4.1 1990 ROD Standards
The 1990 ROD established excavation and treatment standards for each chemical of concern
based on an evaluation of the risk to human health and the environment, federal and state
Applicable or Relevant and Appropriate Requirements (ARARs), and background
considerations. The 1990 FS (SAIC 1990) and ROD (EPA 1990) should be referenced for the
methods and criteria used in the evaluation. Table 4-1 shows the 1990 ROD excavation and
treatment standards for contaminated soils and sediments at the Site and the 1990 ROD aquifer
cleanup and ground water treatment standards and corresponding leachate test procedures.
4.2 1990 ROD Remediation Requirements and Remedial Design
The 1990 ROD for the Site identifies components of the remedy according to media and
contaminant type. For ease of reference, this ROD Amendment will describe the remedy using
the terminology developed in the UAO SOW. The UAO described seven major components and
one interim component of the remedy as follows:
• Component 1 -Excavation, treatment, and on-site disposal of soils contaminated
with inorganics only
• Component 2 -Excavation, Treatment, and on-site disposal of soils contaminated
with organics only
• Component 3 -Excavation, treatment, and on-site disposal of soils contaminated
with organics and inorganics
• Component 4 -Extraction of contaminated groundwater, treatment to remove
inorganics and organics, and discharge of treated groundwater
• Component 5 -Control and treatment of contaminated runoff to prevent
movement of Site chemicals into Beaughton Creek
• Component 6 -Excavation, treatment, and disposal of contaminated sediment
within drainage ditches discharging Site runoff into Beaughton Creek
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• Component? -Perform sediment and trout sampling and other appropriate
aquatic organism sampling, as necessary, of Beaughton Creek; Perform
contaminated sediment removal or other remedial measures as determined by
EPA
• Component 8 -Dust control measures at the J.H. Baxter wood treatment facility
Components 5, 7, and 8 are not modified by this ROD Amendment. For more detail, refer to the
UAO SOW (EPA 1991) and 1990 ROD. Component 6 is modified as described in Section 8.3.8
of this ROD Amendment.
4.3 1990 ROD Remedy Implementation Status for Components within the DNAPL Zone
The WRG is responsible for implementing the 1990 ROD under the UAO. The current status of
these activities for the DNAPL Zone is summarized below.
4.3.1 Subsurface Soils in the DNAPL Zone
Subsurface soils within the DNAPL Zone are defined to extend from greater than 2 feet bgs
through both unsaturated and saturated zones to the OCA. Subsurface soils are composed mainly
of soils contaminated with organics only (Component 2) and soils contaminated with organics
and inorganics (Component 3). Remedial design investigations conducted after the 1990 ROD
have indicated that the extent of affected subsurface soils above and beneath the ground water
table is much greater than initially estimated in the 1990 FS (Grant 1993, Grant 1994, Grant
1995).
A study conducted by ENVIRON Corporation for the WRG questioned the effectiveness of sub-
surface excavation to restore ground water within a reasonable time frame (ENVIRON 1995).
While EPA did not agree with some of the details in this report, EPA did agree to suspend
Remedial Design (RD) schedules for ground water and subsurface soils in the DNAPL Zone
while developing the FFS.
4.3.2 Ground Water
After the 1990 ROD was signed and prior to the issuance of the UAO, an interim ground water
extraction system and a ground water treatment plant (Baxter WTP) were built by the WRG
under orders from the NCRWQCB. The primary function of the interim system has been to treat
surface water runoff. The Baxter WTP includes an oil/water separator, metals precipitation,
biological treatment, and activated carbon adsorption. As described in the Groundwater Remedial
Design Report (RDR) (TRC 1996b), the capacity of the Baxter WTP would be expanded as
needed to treat water from future extraction wells. There is also a 50 gpm treatment plant at the
Roseburg property that is mainly utilized to treat surface water runoff.
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The GWRDI investigated the extent of ground water contamination. The final remedy for the
ground water outside of the target zone is under design. A slurry wall around the DNAPL-
contaminated area is an element of the proposed ground water design that enhances its efficacy
and cost-effectiveness. This ROD Amendment assumes the presence of the ground water
remediation system and slurry wall as a base case.
4.4 Discharge Standards for Beaughton Creek
The 1990 ROD did not provide for the discharge of treated groundwater to Beaughton Creek.
The ROD Amendment recognizes this as a discharge option, although it is the last and least
favored option. The preferred option remains discharge to the Roseburg log decks. The
groundwater treatment standards for discharges to Beaughton Creek are ARARs and are provided
in Table 4-2.
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5.0 COMMUNITY PARTICIPATION
The EPA has encouraged public participation throughout the Remedial Investigation/Feasibility
Study (RI/FS) and Remedial Design/Remedial Action (RD/RA) stages of the project in
accordance with CERCLA requirements. Public participation requirements for EPA's selection of
the final remedy as defined under CERCLA Section 113(k)(2)(B)(i-v) and 117(a) were met by
the activities described below.
Informational meetings and Site tours have been held during the RD/RA phase, with
representatives of public agencies and local citizen groups invited to attend. RD/RA documents,
including the C&TS (Grant 1993), the Draft Preliminary Remediation Design Plan (Grant 1994),
the GWRDI (Grant 1995), and the FFS (Bechtel 1997) were placed in the Administrative Record
for the Site.
The Proposed Plan for the modifications to the groundwater and soils remedy was distributed
using EPA's mailing list for this Site. A public comment period on the proposed plan was held
between September 29 and November 29, 1997. Public notice regarding the public comment
period and articles informing the public of EPA's ongoing activities at the site appeared in the
Siskiyou Daily News and the Weed Press. A formal public meeting was held October 9, 1997.
A transcript of the meeting can be found in the Administrative Record for this Site.
There were four written comments submitted during the public comment period, and two formal
verbal comments were made during the October 9, 1997, public meeting.
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6.0 SCOPE AND ROLE OF DECISION
The selected response actions in the 1990 ROD address contamination in soil, groundwater, and
surface water caused by operations at the Site. The selected response actions in this ROD
Amendment address contamination in soil and groundwater, with emphasis on soil and
groundwater within the DNAPL Zone, caused by operations at the Site. This action revises and
enhances the groundwater remedy selected in the 1990 ROD and addresses additional soil
contamination found in the Roseburg excavation and Area B soils contamination discovered after
issuance of the 1990 ROD. This ROD Amendment also modifies certain aspects of treated
groundwater disposal and soil remedies, and addresses soils exposed by decommissioning of
buildings. Table 6-1 summarizes the selected remedies for all media components at the Site.
6.1 Summary of 1990 ROD Remedy
For the Site, arsenic, carcinogenic PAHs, pentachlorophenol, and dioxins have been identified as
the primary contaminants of concern. All of these contaminants are known or suspected
carcinogens and all are present in each medium at concentrations exceeding health standards.
Chromium, copper, zinc, benzene, and non-carcinogenic PAHs have been identified as secondary
contaminants of concern. These contaminants are considered to be less toxic than the primary
COCs, are not widespread, are relatively immobile, and/or do not consistently exceed health-
based standards.
The selected remedies address the documented potential threats from the Site. The 1990 ROD
selected treatment of the contaminated soil and groundwater to significantly reduce the potential
for future exposure to contaminated soil, groundwater, surface water, particulates, and vapor.
The 1990 ROD cleanup standards for soils, sediment, and groundwater are presented in Table
4-1.
6.1.1 Ground Water Remedy
The uppermost aquifer underlying the Site is primarily impacted by arsenic, chromium, copper,
zinc, carcinogenic and noncarcinogenic PAHs, PCP, and benzene. The remedy selected by the
1990 ROD for groundwater is extraction, biological treatment, chemical treatment, and
discharge. Treatment and discharge standards are the same and are listed in Table 4-1. The 1990
ROD provides that groundwater be treated to meet the cleanup standard prior to reuse or release
from the Site. Under the 1990 ROD, the primary disposal method for treated water was use on the
Roseburg log deck sprinkler system. Other disposal options for'treated groundwater included
reinjection to groundwater, use by industrial processes, use for irrigation, release to subsurface
drains or trenches, and disposal to percolation/evaporation ponds. In the 1990 ROD, EPA
specifically did not include direct discharge to Beaughton Creek as a disposal option.
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6.1.2 Soils Remedy
The 1990 ROD divided contaminated soils into three categories based on the types of chemicals
present in the soils. The remedy selected for soils is specific to each area and the type of
contamination present. The remedy addresses the following contaminants:
Component 1:
Component 1 soils contain only inorganic constituents exceeding the standards specified in the
1990 ROD. Inorganic contaminants at the Site are arsenic, chromium, copper, and zinc. The
remedy selected by the 1990 ROD for Component 1 soils is excavation, treatment through
fixation, and disposal. Excavation and treatment standards for inorganic contaminants in the
surface and subsurface are listed in Table 4-1. The 1990 ROD provides that treated soils meeting
the treatment standards may be placed back onto the Site in accordance with CCR Title 22
requirements. The 1990 ROD and UAO-SOW require that soils that do not meet the treatment
standards are to be disposed in lined disposal cells sited and constructed according to RCRA and
CCR Title 23, Chapter 15 standards (i.e., RCRA-equivalent disposal cells).
Component 2:
Component 2 soils contain only organic contaminants, primarily polycyclic aromatic
hydrocarbons (PAHs), and also PCP and dioxins/furans in concentrations exceeding the 1990
ROD standards. The 1990 ROD remedy for Component 2 soils provides for excavation of
impacted soils to the point where the ground water table prevents effective removal. Excavation
of soils is expected to occur when ground water is at or near its lowest levels. The 1990 ROD
anticipates that organic contaminants below the water table will be removed by the ground water
extraction portion of the remedy. Excavated Component 2 soils are to be bioremediated in lined
treatment cells. Excavation and treatment standards for organic contaminants in the surface and
subsurface are included in Table 4-1. After treatment, the treatment cells are to be closed. Siting
and construction of the onsite treatment and disposal cells (RCRA equivalent disposal cell) are to
be in accordance with RCRA and CCR Title 23, Chapter 15 standards.
Component 3:
Component 3 soils contain both organic and inorganic contaminants exceeding the 1990 ROD
standards. The 1990 ROD remedy for Component 3 soils, as with that for Component 2 soils,
provides for excavation of impacted soils to the point where the ground water table prevents
effective removal. According to the 1990 ROD, treatment of Component 3 soils would be
accomplished in two stages: (1) bioremediation to reduce organic concentrations to 1990 ROD
treatment standards, and (2) fixation to reduce inorganic concentrations to 1990 ROD treatment
standards. The treated soils would be disposed of in onsite cells sited and constructed in
accordance with RCRA and CCR Title 23, Chapter 15 standards.
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6.2 ROD Amendment
This ROD Amendment provides a revised remedy for groundwater and subsurface soils within
the DNAPL Zone, several modifications to other aspects of the soils remedy, a revision to the
Beaughton Creek discharge option, and a revision to the remedy for sediments. The soils
remedies selected by the 1990 ROD still pertain to subsurface soils outside the DNAPL Zone and
surface soils both within and outside the DNAPL Zone.
In 1997, EPA issued the FFS (Bechtel 1997) which was developed to reevaluate the remedial
action alternatives for DNAPL-impacted subsurface soils and ground water at the Site. In
addition to the significant increase in the understanding of the volume and extent of DNAPLs in
the subsurface, EPA's understanding of the technical issues for remediation of DNAPL-
contaminated sites has continued to evolve since the FS (SAIC 1990) was completed. The
purpose of the FFS was to reevaluate the 1990 FS remedial action alternatives and consider
additional remedial action alternatives for subsurface soils and ground water within the area
impacted by DNAPLs. taking into consideration:
• The additional Site characterization data obtained since the 1990 FS,
• Technology advances that have occurred since the 1990 FS which may affect
selection of an alternative, and
• Increased understanding of the technology issues associated with DNAPL
remediation based on experience at other sites.
The FFS screened nine alternatives for their ability to clean up groundwater within the DNAPL
Zone to 1990 ROD standards. The alternatives evaluated represented a broad range of
technologies and costs. The alternatives were evaluated with respect to their:
• Effectiveness at removing enough of the DNAPLs so that groundwater would not
continue to become contaminated over time,
• Implementability, and
• Cost.
None of the alternatives were found certain to be effective and implementable. Therefore, EPA
concluded that it is not possible to achieve the 1990 ROD cleanup standards for groundwater
within the DNAPL Zone. For this reason, this area of the Site is also referred to as the Technical
Impracticability (TI) zone for groundwater cleanup.
Additional modifications addressed in this ROD Amendment include:
• Addition of the option of direct discharge to Beaughton Creek for treated water based on
NCRWQCB regulatory actions to require treatment of water to best practicable methods.
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• Covering surface soils containing inorganic concentrations above background and below the
1990 ROD subsurface soil excavation standard with a protective asphaltic concrete surface,
rather than excavating and reburying the soils on-site at a depth greater than two feet.
• Modifying the 1990 ROD treatment standard for soils to be placed in a RCRA-equivalent
disposal cells by modifying the leachate test procedure.
• Broadening the implementation options for biotreatment of soils contaminated with organics
to allow treatment in place (in situ), with appropriate monitoring and controls, followed by
excavation and disposal in a RCRA-equivalent disposal cell.
• Evaluation of in situ bioventing as the treatment technology for Area B soils and covering
these soils with two feet of clean fill.
• Designation of three features of the remedy as RCRA Corrective Action Management Units
(CAMUs): The RCRA-equivalent disposal cell, the soil staging and fixation area, and the
slurry wall construction zone.
• Covering the open excavation on the Roseburg property with a minimum of two feet of clean
soil.
• Modification of the 1990 ROD subsurface soil excavation standards for
organics-contaminated soils outside the DNAPL Zone to ensure that they remain protective
of groundwater.
• Modification of the requirements for excavation, treatment, and disposal of contaminated
sediments within drainage ditches discharging Site runoff into Beaughton Creek to permit
natural flushing and attenuation.
• Collection and treatment of liquids from DNAPL seeps in the Roseburg excavation.
• Implementing institutional controls to prevent exposure to waste left in the DNAPL Zone and
to protect the integrity of the remedy.
• Requiring the development of a soils handling plan to address instances where building
decommissioning/construction activities, routine maintenance, or other ground intrusive
activities on site may occur.
Sections 7 and 8 of the ROD Amendment analyze the cleanup alternatives for the DNAPL Zone.
Section 8 explains the modifications to the remedy related to the DNAPL Zone and discusses the
additional modifications to the remedy for soils, sediment, and discharge to Beaughton Creek.
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7.0 DESCRIPTION OF ALTERNATIVES FOR THE DNAPL ZONE
EPA identified and evaluated three cleanup alternatives for the DNAPL Zone, also known as the
TI Zone. All of the alternatives incorporate containment rather than clean up of groundwater
within the DNAPL Zone due to the technical impracticability of remediating groundwater where
DNAPLs are present in the saturated zone. The following cleanup alternatives were evaluated in
detail. The remedial alternatives considered for detailed evaluation are Alternatives 1, 2, and 3,
which were retained in the preliminary screening, conducted in the FFS:
Alternative 1 - No Further Action. The No Further Action alternative, which incorporates slurry
wall containment of the DNAPL-contaminated subsurface soils in the DNAPL Zone, is retained
throughout this analysis as the baseline case. The slurry wall was added as a component of the
remedial design to enhance the restoration of groundwater outside of the DNAPL Zone. The
remedy, without a slurry wall, will not be protective of human health and the environment.
Alternative 2 - Excavation to Ground Water Table after Slurry Wall Dewatering. Ex-Situ
Biotreatment. Stabilization, and On-site Disposal of Treated Soils. This alternative is retained
because it originates from the 1990 ROD remedy for subsurface soils and provides additional
exposure control, which is part of the revised Remedial Action Objectives (RAOs) for subsurface
soils.
Alternative 3 - Additional Containment and Institutional Controls. This alternative incorporates
several protective measures into the No Further Action alternative through additional
containment measures and institutional controls. Alternative 3 did not meet the 1990 ROD
RAOs, but was retained, consistent with EPA's feasibility study guidance, since it provides a
further degree of protectiveness over the No Further Action alternative at a relatively low
increment in cost.
7.1 Alternative 1 - No Further Action
The FFS and this ROD Amendment assume a baseline remedy for groundwater and soils cleanup
other than groundwater and subsurface soils within the DNAPL Zone in accordance with the
1990 ROD. The baseline remedy provides that the groundwater outside of the DNAPL Zone will
still be restored by pumping and treatment, to the standards selected by the 1990 ROD (See Table
4-1). This aspect of the remedy will be enhanced by constructing a slurry wall around the
DNAPL Zone. A slurry wall is a physical barrier that would prevent the flow of groundwater
through the DNAPL area, thereby preventing further contamination and facilitating faster cleanup
of the groundwater outside of the DNAPL Zone.
Because this baseline is now part of a containment strategy, it is important to reduce the mobility
of the DNAPLs that will not be excavated. Any pooling of DNAPL due to dewatering within the
slurry wall would be detected and removed in order to reduce saturation and mobility. Other
aspects of the slurry wall installation include: extraction of some groundwater within the
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DNAPL Zone to maintain an inward gradient: treatment and disposal of extracted groundwater,
preferably by reuse on Roseburg's log decks; and a monitoring system to detect any leakage
across the slurry wall, or down through the naturally occurring aquitard. Construction of a slurry
wall is a proven, effective method of achieving containment
7.2 Alternative 2 - Excavation to Ground Water Table After Slurry Wall Dewatering. Ex-Situ
Biotreatment, Stabilization, and On-site Disposal of Treated Soils
This alternative incorporates additional measures beyond the baseline remedy (Alternative 1).
Construction of the slurry wall and implementation of the inward hydraulic gradient are expected
to result in some dewatering within the DNAPL Zone. Affected subsurface soils would then be
excavated to a depth at which the groundwater prevents effective removal. Based on the
estimated volume of soil containing DNAPLs, the minimum volume to be excavated is estimated
to be more than 100,000 cubic yards. This volume could increase significantly depending on the
amount of additional soil that is contaminated but does not contain DNAPLs.
Excavated soils would be biotreated to clean up organic contamination, stabilized using fixation
for inorganic contamination, and disposed in lined cells on site. As stated in the 1990 ROD, all
treated soil would either remain in the treatment cells or would be disposed of in accordance with
RCRA Part 264 and 23 CCR Chapter 15 standards. The cells used for final disposal will be built
in accordance with RCRA Pan 264 and 23 CCR Chapter 15 standards. Disposal in accordance
with the RCRA requirements would also require installation of monitoring wells in the upper and
lower aquifers, closure, capping and long-term monitoring of the biocells.
7.3 Alternative 3 - Additional Containment and Institutional Controls
Under this alternative, additional containment measures would be undertaken after
implementation of the baseline remedy (Alternative 1). This alternative was described and
evaluated in the preliminary screening performed in the FFS, and was retained, consistent with
EPA's feasibility study guidance, since it provides a further degree of protectiveness over the No
Further Action case at a relatively low increment in cost. This alternative includes additional
containment of contaminated soils at the Roseburg Excavation (not included in the 1990 FS and
ROD) and institutional controls for wastes left in the DNAPL Zone.
Additional Containment of Contaminated Soils. The Roseburg Excavation is an open excavation
on the Roseburg property that covers approximately 6.5 acres. The deepest point in the
excavation is estimated to be 14 ft bgs based on the information provided in the Technical
Memorandum, Proposed Interim Remedial Measures, Roseburg Excavation Area, J. H. Baxter
Superfund Site (Environmental Solutions 1996b). The Roseburg Excavation acts as a collection
point for contaminated surface runoff and increases surface water infiltration into the subsurface.
As an additional containment measure beyond the baseline case, this component of Alternative 3
would include regrading the Roseburg Excavation to improve surface drainage and reduce
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infiltration, and placing a minimum of 2 feet of protective soil cover over the area. The soil
cover would reduce the contact of surface runoff with contaminated soils within the Roseburg
Excavation area, and reduce the potential for worker exposure to contaminated soils. In addition,
liquids from DNAPL within the excavation would be collected and treated.
Institutional Controls for the DNAPL Zone within the Slurry Wall Because this alternative
leaves waste in place, institutional controls would be implemented to prevent exposure to wastes
left in the DNAPL Zone. These controls are also necessary to protect the integrity of the remedy,
including the cap and the slurry wall. These controls would include:
a. limiting future land uses to appropriate industrial uses (and prohibiting other
uses);
b. restricting access to and use of contaminated groundwater;
c. prohibiting activities that would disturb the integrity of the remedy, including
appropriate prohibitions on activities that would disturb the soil and/or any cap
placed upon such soil;
d. requiring appropriate handling of excavated materials;
e. providing for appropriate notice (in land records and otherwise) that hazardous
wastes remain on site; and
f. prohibiting other activities that could cause a potential threat to human health or
the environment.
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8.0 SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES
An evaluation and comparison of the alternatives for the DNAPL Zone is presented in this
Section. For each of the other modifications to the remedies selected in the 1990 ROD. a brief
summary and a table of the NCP criteria analyses is presented.
8.1 Comparative NCP Critera Analyses of Alternatives for the DNAPL Zone
In this section, the three remedial alternatives for the DNAPL Zone are evaluated in relation to
one another for each of the nine evaluation criteria. As described in Section 7, the three
alternatives retained in the preliminary'screening conducted in the FFS are:
Alternative 1 - No Further Action (Baseline including 1990 ROD Remedy and Slurry Wall)
Alternative 2 - Excavation to Ground Water Table after Slurry Wall Dewatering, Ex-Situ
Biotreatment, Stabilization, and On-site Disposal of Treated Soil
Alternative 3 - Additional Containment and Institutional Controls
The comparison of alternatives is based on the nine key criteria required under the NCP and
CERCLA Section 121 for use in evaluation of remedial alternatives by EPA. The nine criteria
are as follows:
1. Overall protection of human health and the environment
2. Compliance with Applicable or Relevant and Appropriate Requirements
3. Long-term effectiveness and permanence
4. Reduction of toxicity, mobility and volume through treatment
5. Short-term effectiveness
6. Implementability
7. Cost
8. State acceptance
9. Community acceptance
Table 8-1 presents a summary of the comparative analysis.
8.1.1 Overall Protection of Human Health and the Environment
Both Alternatives 2 and 3 have a higher degree of overall protectiveness than Alternative 1.
Alternative 1 achieves only containment of the DNAPL Zone within the Target Area but does not
achieve exposure control, and is, therefore, the least protective of the three alternatives. When
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Alternatives 2 and 3 are compared, Alternative 2 appears to have a somewhat higher degree of
protectiveness over Alternative 3 due to the removal and treatment of significant quantities of
impacted soils. Long term permanence is also greater, again due to the removal and treatment
actions. However, overall protectiveness of Alternative 2 in comparison to Alternative 3 is
countered by the fact that subsurface soils, although contaminated, do not pose an immediate
risk. These soils are not currently exposed. Additionally, the short-term risks to human health and
the environment posed during implementation of Alternative 2 are greater than those under
Alternative 3. Assuming that institutional controls are put in place, Alternative 3 would achieve
the proposed revised RAOs. This alternative protects human health and the environment by
containing the DNAPL Zone within the Target Area and by reducing the potential risks of
ingestion of contaminated ground water and contact with contaminated subsurface soils through
the use of institutional controls.
For all three alternatives, the overall risk of further migration of DNAPL from the upper aquifer
is reduced by slurry wall containment of the DNAPL Zone and by implementation of the
associated hydraulic control measures as proposed in the Groundwater RDR (TRC 1996b). The
slurry wall is intended to minimize the risk of further horizontal migration of DNAPL
contaminants beyond the DNAPL Zone. Based on available data, the aquitard layer (OCA)
underneath the Site is assumed to provide effective vertical containment of the DNAPL in the
DNAPL Zone, and vertical DNAPL migration due to dewatering during implementation of the
slurry wall containment will be monitored and controlled. The ground water remedial design,
when finalized, will include a monitoring program for the upper and lower aquifers which is
intended to verify the effectiveness of the OCA as an aquitard and the proposed slurry wall as a
containment remedy. The design will also include contingency plans to take corrective actions
should monitoring data indicate a need for these actions.
Without further controls to minimize access to ground water within the proposed slurry wall area,
Alternative 1 would not reduce the potential risk of exposure to contaminants through ingestion
of the ground water underlying the Site. Nor does Alternative 1 include any protective measures
to reduce the potential for exposure to contaminants present in the shallow subsurface soils.
Although there is no existing pathway at present, without removal under Alternative 2 or
institutional controls under Alternative 3, exposure to contaminants in the shallow subsurface
soils is plausible under a trespassing and/or excavation scenario.
Alternative 2 would minimize the potential for exposure of future industrial workers (or to other
potential receptors such as trespassers, children, etc.) to contaminants in the subsurface soils by
removing a significant portion of the contaminated subsurface soils. However, based on
available site characterization data, it is estimated that even with soil excavation, up to 40 percent
of the estimated DNAPL-impacted subsurface soils would be remaining under the anticipated
ground water table after slurry wall dewatering is implemented. Therefore, removal of most of
the source material mass in the vadose zone is not expected to reduce DNAPL to the amount
required to restore the upper aquifer to the 1990 ROD cleanup standards within the proposed
slurry wall area. Alternative 2, therefore, would need to be supplemented with institutional
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controls prohibiting well drilling within the DNAPL Zone in order to minimize the risk of
ingestion of contaminated ground water.
Alternative 3 includes regrading and placement of a protective soil cover for the Roseburg
Excavation. This area is currently acting as a collection point for contaminated surface water
runoff that leaches into the subsurface. Regrading and placing a protective soil cover over the
Roseburg Excavation would reduce the potential for surface water contamination due to contact
with contaminated soils, and reduce infiltration by eliminating surface water pooling. The
potential for worker exposure to contaminants of concern would also be reduced by placement of
the protective cover over the area.
8.1.2 Compliance With ARARs
Adoption of any of the three alternatives would require a waiver of the ground water cleanup
standards set forth in the 1990 ROD based on the technical impracticability (TI) from an
engineering perspective for ground water restoration within the DNAPL Zone. On this basis the
DNAPL Zone is also referred to as the TI Zone. EPA has waived these ARARs on the basis of
technical impracticability in accordance with CERCLA section 121(d)(4)(c), 42 U.S.C. section
9621 (d) (4)(c). The three alternatives do not modify the other elements of the remedy selected in
the 1990 ROD. Consequently, the three alternatives comply with the ARARs set forth in the
1990 ROD (Tables 8-2 and 8-3). However, Section 8.3 of the ROD Amendment discusses
additional modification to the remedy, and the ARARs implications of these additional
modifications are discussed in Section 10.2.
The ARARs specific to the slurry wall are included in Table 8-4. Because the area within the
slurry wall containment system is not a "waste management unit," the substantive requirements
of the sections of Chapter 15 cited in Table 8-4 are "relevant and appropriate" to the
implementation of the proposed slurry wall containment system. The requirements cited in Table
8-4 would apply to ensure that the slurry wall containment system effectively precludes the
constituents of concern from reaching the lower aquifer, which has been designated for municipal
and domestic water supply.
8.1.3 Long-Term Effectiveness and Permanence
In addition to the baseline slurry wall containment of DNAPL within the TI Zone, Alternative 2
provides the highest long-term effectiveness and permanence of the three alternatives, since a
significant portion of the impacted soils would be removed, treated, placed in a RCRA-
equivalent disposal cell, and be subject to long-term monitoring. Alternative 3 has the next
highest long-term effectiveness and permanence since the Roseburg Excavation would be
covered, minimizing this source for surface runoff contamination and subsurface leaching.
Alternative 1 would be least effective in the long-term.
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The inclusion of the slurry wall, hydraulic controls, and a ground water monitoring program as
the baseline for all three alternatives provides reliable containment assuming continual
maintenance of the wall and mechanical systems. The long-term reliability of the slurry wall
containment depends on continued ground water monitoring to evaluate and upgrade its
effectiveness, on continued slurry wall maintenance, and on implementing contingency measures
when required. The objective is containment of the DNAPL within the DNAPL Zone. Literature
indicates that, when built properly, slurry wall systems can be effective containment measures for
the long term (Rumer, R. R. and Ryan M. E., Barrier Containment Technologies for
Environmental Remediation Applications, 1995).
A major factor affecting the long-term effectiveness and permanence of the proposed slurry wall
is the wall's integrity and overall performance as a low permeability barrier. For example,
defects during its construction could cause localized areas of higher permeability. Construction
quality assurance/quality control (QA/QC) measures are, therefore, particularly important during
implementation of this remedial action. Potential long-term changes in the permeability of the
slurry wall could also result from (1) wetting and drying of the section of the wall which is
exposed to the fluctuating ground water table, (2) desiccation of the backfill, (3) freezing and
thawing cycles, and (4) chemical incompatibility.
Wetting and drying and/or desiccation are not concerns for the proposed design because -a
hydraulic gradient (inward) would always be maintained across the slurry wall. Also the
proposed gravel drainage trench would prevent an extreme rise in the ground water table outside
the southern boundary of the slurry wall. Freezing and thawing is not a concern because the
freezing depth does not extend beyond the slurry wall cap depth for the anticipated climatic
conditions at the Site. Chemical incompatibility of the slurry wall backfill mix with the
hazardous substances, pollutants or contaminants that are being contained could also potentially
cause an increase in the permeability of the slurry wall over the long term. The literature
indicates that highly concentrated organic compounds can result in increased hydraulic
conductivity within the slurry wall (Rumer, R. R. and Riley, M. E., 1995). However, the
alignment of the proposed slurry wall has been designed such that the slurry wall bypasses the
high concentration DNAPL areas. Therefore, chemical compatibility is not anticipated to be a
problem provided that proper construction QA/QC procedures are implemented to prevent
entrainment of DNAPL in the slurry wall backfill if DNAPL should be encountered.
Effectiveness of the slurry wall containment system also depends on implementation of hydraulic
control measures. The effectiveness of the hydraulic control measures will be assessed through
the monitoring programs. If needed, corrective action will be taken according to the contingency
plans outlined in Section 9.2. The contingency plans also include the repair and replacement
actions that may be implemented based on the monitoring data.
For Alternative 2, the excavation, treatment, and on-site disposal of treated subsurface soils
ensures a permanent remedy for that portion of area soils that are treated to 1990 ROD treatment
standards. However, the on-site RCRA disposal cell would also require long-term maintenance,
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monitoring, and corrective action if necessary. Significant quantities of impacted subsurface
soils, however, would still remain in the DNAPL Zone under this alternative, both in the
saturated zone (35 to 45 ft bgs) and under existing buildings.
For Alternative 3, regrading and placement of a protective cover at the Roseburg Excavation
would prevent further contact of surface water with contaminated soils currently in the open
excavation area. However, since hazardous wastes would be left in place, this remedy would not
be considered permanent. Therefore, controls designed to avoid the likelihood of failure over the
course of time would need to be adopted.
With respect to the risks remaining at the Site after the required remediation has been performed,
only Alternative 3 provides controls to prevent the exposure to contaminants through ingestion of
the impacted ground water and to minimize the potential pathway for exposure to contaminants
left in the subsurface soils. The ability to ensure effective controls over the long term is
dependent on several factors, including the compliance of the landowners with institutional
controls.
8.1.4 Reduction of Toxicity, Mobility, or Volume through Treatment
The highest reduction in toxicity, mobility, and volume of contaminants is achieved through
treatment and disposal under Alternative 2, since a significant portion of the impacted subsurface
soils would be excavated, treated, and disposed of in a RCRA-equivalent cell. Alternative 3
would have the second highest reduction in mobility since the Roseburg Excavation would be
covered with clean soil, followed by Alternative 1, which would only reduce the mobility of
DNAPL and aqueous phase contaminants within the TI Zone by use of slurry wall containment
system. The slurry wall containment system is also included under Alternatives 2 and 3.
Under Alternatives 1 and 3, toxicity of the contaminants in the subsurface soils within the
DNAPL Zone would not be reduced. The toxicity of the contaminants of concern in ground
water within the DNAPL Zone would gradually decrease due to the flushing effect of the
proposed extraction system. However, this would happen over a long period of time and toxicity
reduction will probably be negligible. Mobility of the contaminants of concern from both soil and
ground water within the DNAPL Zone would be reduced since the slurry wall would act as a
physical barrier to further migration of the contaminants of concern beyond the DNAPL Zone.
The volume of the impacted subsurface soils would not be changed under Alternatives 1 and 3.
However, the proposed slurry wall would provide an upgradient barrier to ground water flowing
into this area, and would prevent additional ground water from being impacted. Consequently,
dewatering of the DNAPL Zone combined with the above-ground treatment of the extracted
ground water would reduce to some extent the volume of contaminated ground water.
Alternative 2 reduces the mobility of DNAPL contaminants by slurry wall containment within
the DNAPL Zone, and reduces both the volume and toxicity of a substantial portion of
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subsurface soil contamination through removal and treatment. Total soil volume to be treated is
estimated to be 107,600 cubic yards (in-place), based on the minimum impacted soil estimate,
and 719.000 cubic yards (in-place), based on the maximum impacted soil estimate. Under this
alternative, it is believed that up to 40 percent of the DNAPL-impacted subsurface soils that are
currently in the saturated zone would potentially remain under the anticipated ground water table
after slurry wall dewatering is implemented. Additionally, it is assumed that the soils underneath
the buildings would not be excavated. Based on these assumptions, approximately 64,000 cubic
yards of contaminated soil would be left in place, based on the minimum impacted soil volume
estimate, and approximately 565,000 cubic yards, based on the maximum impacted soil volume
estimate.
With respect to subsurface soils to be excavated and treated under Alternative 2, the treatment
process for organic contaminants, biodegradation, provides a permanent reduction in toxicity and
volume. However, the treatment method for remaining inorganic contaminants, immobilization
through stabilization, does not destroy the contaminants and thus may be partially reversible
should the stabilized soil break down over time. Placement of treated soil into an on-site RCRA-
equivalent disposal cell would further reduce the possibility of future impacts from treated soil
left on-site.
Under Alternative 3, the potential for contamination of surface water is reduced through
regrading and placement of the protective soil cover over the Roseburg Excavation. This would
reduce the mobility of PAHs since infiltration of surface water runoff would be reduced.
8.1.5 Short-Term Effectiveness
Alternative 1 has the highest short-term effectiveness since the risks posed to the community or
site workers during implementation are the least under this alternative. Alternative 3 has the next
highest short-term effectiveness, since some short-term risks exist in connection with the
transportation of soil to the Site and with the regrading and covering of the Roseburg Excavation.
No short-term risks are involved in the implementation of the proposed institutional controls.
Alternative 2 has the lowest short-term effectiveness because of the volume of soil and the
complexity of the soil handling, storage, treatment, and disposal steps that would be involved in
the implementation of this remedy.
Under all three alternatives, there could potentially be some short-term risk to construction
workers from fugitive dust emitted during the excavation of soils for construction of the slurry
wall. Also, for Alternative 3, there is potential for worker exposure to contaminants during
regrading and placement of the protective soil cover on the Roseburg Excavation area due to
contaminated fugitive dust. Therefore, effective dust control measures would be necessary
during remediation activities. Workers would need to be equipped with appropriate personal
protective equipment (PPE) during excavation through potentially contaminated subsurface soils.
Soil sampling would be implemented during excavation to identify the impacted soils, and the
impacted soils would be removed and disposed of appropriately. These same measures would be
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applied during treatment and disposal of contaminated subsurface soils to enhance the short-term
protectiveness of Alternative 2.
During slurry wall excavation activities, if free-phase DNAPL is encountered, this could also
result in worker exposure to concentrated hazardous substances, and potentially in uncontrolled
DNAPL migration. However, this is not anticipated based on available site characterization data.
If the OCA is penetrated during slurry wall excavation, adverse environmental impacts could
occur due to the potential risk of further migration of the DNAPL. Excavation for the slurry wall
must be conducted with great caution in order not to penetrate the OCA, especially in areas
where the OCA layer is known to be less than 5 ft thick.
The short-term effects of Alternative 2 on human health and the environment are of the type that
are controllable through standard health and safety precautions and good construction practices.
For Alternative 3, transportation of between 12,000 and 33,400 cubic yards of clean imported
soil to the Site for the soil cover placement operation would pose a short-term safety issue since
there would be an increased potential for vehicular accidents due to increased truck traffic.
The time to physically implement Alternative 1 and achieve protection through source control is
estimated to be approximately 1 year based on the implementation schedule provided in the
Groundwater RDR (TRC 1996b). The time required to achieve protection through
implementation of Alternative 2 is estimated at from 3 to 5 years for the minimum soils volume
estimated and 5 to 7 tears for the maximum soil volume estimate. A minimum of 1 year is
estimated for development, submittal and approval of remedial design and remedial action plans
and specifications. Alternative 3, including the soil cover placement operation, could be achieved
within 1 to 2 years.
8.1.6 Implementability
The effectiveness of institutional controls will depend on the compliance of current and future
landowners. In other respects, Alternative 3 is highly implementable. Since the proposed slurry
wall containment system is relatively easy to implement, it will meet the proposed revised RAOs
for the Target Area, and it has a low impact on the community and on operations at the Baxter
plant. Alternative 1 is also easy to implement but it would not meet the proposed revised RAOs
for exposure control. Alternative 2, which is based on the ROD remedy, is least implementable
because of the excessive soil volumes that would need to be excavated, treated, and disposed of
in an RCRA-equivalent cell, and because of the significant impact these operations would have
on the community and Baxter plant operations.
For all three alternatives, the proposed slurry wall, which would be constructed to an average
depth of 45 ft, is technically feasible; slurry walls have been used extensively as containment
measures. The expertise, services, equipment, and material needed are available. Construction
of a slurry wall around the DNAPL Zone with the proposed alignment does not interfere with
other remedial alternatives, should other remedial actions be implemented in the future. It might,
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however, require temporary relocation of some of the subsurface utility lines. Also, the presence
of the slurry wall enhances the potential for remediation or restoration of the aquifer outside the
DNAPL Zone. Long-term monitoring as planned would provide the basis for the assessment of
the effectiveness of the containment measure implemented. Based on monitoring results, the
monitoring well network and/or the plan could be expanded, if required.
Several factors need to be considered during implementation of the slurry wall. Defects during
construction of the slurry wall could lead to high permeability areas in the slurry wall. Defects
could potentially be caused by use of nonhomogeneous backfill resulting from improper mixing.
If improperly mixed, the backfill material could include lumps of unmixed soil or pockets of free
slurry not fully blended with soil. Also, if the trench is allowed to remain open for too long,
sediment could accumulate and become trapped beneath the backfill. Cave-in of the trench sides
could also occur. These potential problems would be mitigated by proper construction QA/QC
measures.
For Alternative 2 and Alternative 3, technology, equipment, and services for the excavation and
treatment processes and for regrading and placement of the soil cover, respectively, are also
readily available, and relatively easily implemented. However, the large quantities of imported
soil that would be needed for backfilling the excavated areas may not be readily available from a
nearby source. For Alternative 2 and Alternative 3, transportation of the imported soil may
impact the implementability of these remedies. Alternative 3 would require that from 600 to
1,670 truck loads (assuming 20 cubic yards trailer trucks). This could have a significant impact
on both the cost and practical implementability of these alternatives.
For Alternative 2, extensive land areas required for soil treatment by landfarming may pose a
problem, in addition to the land area needed for the on-site RCRA disposal cell(s). The
reliability of excavation in removing the contaminants of concern would depend on the accuracy
of delineation of the extent of contamination in subsurface soils. Landfarming has been shown to
be reliable in reducing the levels of PAH and PCP soil constituents to between 50 percent and
100 percent. Stabilization has been demonstrated to be completely effective in reducing
leachability of inorganic constituents to nondetectable levels. Monitoring of the effectiveness of
the bioremediation and stabilization processes will be accomplished through in-process and
confirmation sampling and analysis.
Implementation of other remedial actions simultaneously would be seriously limited during
execution of Alternative 2 in the DNAPL Zone. Excavation and landfarming of up to 900,000
cubic yards of soil would consume space and equipment resources at the Site throughout the
duration of field activities. Implementation of Alternative 2 might also interfere with
commercial operations at the Site, which could potentially cause an adverse economic impact on
the community.
The implementability of Alternative 3's institutional controls is dependent on the compliance of
the affected landowners and the ability of each level of government (federal, state, and local) to
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use their respective authorities to impose and enforce institutional controls. Material and
services for fencing and other access restrictions, if required, would be readily available.
8.1.7 Cost
All alternatives assume as baseline the cost of the proposed slurry wall containment and
hydraulic control system. When the alternatives are compared on the basis of cost effectiveness
above the baseline. Alternative 3 is rated the most cost effective. The cost of Alternative 2 is
very high. The cost of Alternative 1 is the baseline cost only. A cost comparison summary is
presented in Table 8-5.
No incremental costs above the baseline cost are included under Alternative 1, since this
alternative includes No Further Action beyond the baseline. The cost of implementing the slurry
wail containment, associated hydraulic controls, planned modifications to the ground water
treatment plants, ground water monitoring wells, and the 30-year present worth of operations,
maintenance, and monitoring costs are estimated to be approximately $10.9 million based on the
Groundwater RDR (TRC 1996b).
The incremental cost of Alternative 2 above the baseline (i.e., excluding installation of the slurry
wall, hydraulic control and ground water monitoring) is estimated to be between $26,000,000 for
the minimum impacted soil volume estimate, and $160,000,000 for the maximum impacted soil
volume estimate. Major components of the capital cost estimate are inclusive of site preparation;
soil excavation/backfill activities; soil screening; construction of biocells and a RCRA disposal
cell; ex-situ biotreatment by landfarrning; soil stabilization by fixation of inorganic
contaminants; leachate collection/treatment; project sampling and analysis; monitoring well
installation and operation; capping and closure. The annual operating and maintenance (O&M)
cost of this alternative includes cap maintenance, RCRA ground water monitoring wells
(quarterly sampling program) and a 5-year review. Annual O&M cost for the minimum volume
is estimated to be $46,000, and that for the maximum volume is estimated at $102,000. Annual
O&M costs do not include 5-year review costs, which are estimated at $30,000 per review, and
are included in the 30-year Present Worth Analysis. Total incremental cost is presented as
capital cost plus present worth of O&M costs.
The incremental capital cost of Alternative 3 above the No Further Action alternative is
estimated to be approximately $1,000,000. The major components of the capital cost are the
costs of imported soil, equipment, and labor for regrading and placement of protective soil cover
over the Roseburg Excavation area. Costs for fencing, gates, and administrative expenses for
deed restrictions are also included. The annual O&M costs include the maintenance of the fences.
The O&M cost of this alternative is therefore minimal, and is estimated to be $8,000 per year for
the maintenance activities, and $30,000 every 5 years for the required 5-year review. The total
cost of this alternative based on a 30-year present worth of the O&M and review costs is
estimated to be $1,300,000 using a discount rate of 5 percent.
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For both Alternative 2 and Alternative 3 indirect capital costs such as engineering, procurement
and construction management (EPCM) are assumed to be 15 percent of the direct capital costs.
Contingency is taken as 30 percent of direct and indirect capital costs.
8.1.8 State Acceptance
Both Alternatives 2 and 3 are acceptable in concept to the State, but Alternative 3 is preferred.
Alternative 1 is not acceptable to the State.
8.1.9 Community Acceptance
Alternative 3 is acceptable to the community. Alternatives 1 and 2 are not acceptable to the
community.
8.2 Overall Ranking of Alternatives for the DNAPL Zone
Based on the above factors, if the institutional controls associated with Alternative 3 can be
effectively implemented. Alternative 3 would be the highest ranking alternative. This alternative
meets the proposed revised RAOs for exposure and source control, is protective of human health
and the environment, is technically implementable within a reasonable time at a reasonable cost,
and does not pose significant short-term risks. The implementability of the institutional controls
is dependent on the compliance of the affected landowners and the ability of each level of
government (federal, state, and local) to use their respective authorities to impose and enforce
such controls. The long-term effectiveness and reliability of this remedy in turn would depend
on proper implementation of the proposed institutional controls. Alternative 2 is rated as the
second highest alternative since it achieves the proposed revised RAOs for exposure control for
the subsurface soils and source control for ground water, and provides a somewhat higher degree
of protectiveness than Alternative 1, albeit at very high cost. Alternative 1 is the lowest ranking
alternative since it does not meet the proposed revised RAOs for exposure control.
8.3 NCP criteria Analyses for Additional Remedy Modifications
This section describes and analyzes each of the additional remedy modifications. Tables 8-6
through 8-10 present a summary of the nine criteria analysis under the NCP for each of the major
modifications.
8.3.1 Modification for Disposal of Treated Water
EPA is modifying the disposal options for treated water at the Baxter site to include direct
discharge to Beaughton Creek, although the preferred disposal option will remain reuse on
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Roseburg's log decks. The 1990 ROD prohibited the direct discharge of treated ground water to
Beaughton Creek. This prohibition was based on the NCRWQCB Water Quality Control Plan,
which does not allow routine discharges to surface water and includes water quality objectives
and receiving water limitations. Additionally, pursuant to the RWQCB discharge orders No. 93-
87 and No. 93-88, the remediation system for the Site is to be operated in a manner which
minimizes discharges to surface water by first considering other disposal options.
The 1990 ROD stated EPA's intent to work closely with the NCRWQCB and the PRPs to
identify additional disposal options agreeable to all. As a result, the option of direct discharge to
Beaughton Creek has been added to this ROD Amendment based on RWQCB regulatory action
to require treatment of water to best practicable methods. The water treatment system must be
operated in a manner that minimizes discharges to Beaughton Creek by preliminarily considering
the use of the other disposal options allowed by the ROD, leaving discharge to Beaughton Creek
as a last and least favored option.
8.3.2 Surface Soils Containing Inorganic Concentrations above Background and below the
1990 ROD Subsurface Soil Excavation Standard
This ROD Amendment modifies pan of the remedy for surface soil contaminated with inorganic
compounds only. The 1990 ROD requires excavation of surface soils contaminated with
inorganics if the concentration of contaminants exceeds the ROD surface soil excavation
standards set forth in Table 4-1. The risk-based surface soil excavation standard required the
excavation of surface soils contaminated with above background levels of arsenic, or above risk
levels of chromium, copper, or zinc. The surface soil excavation standard was based on
background arsenic levels and reflects the potential risk of surface exposure.
Soils with contaminant concentrations below the subsurface soil excavation standard but above
the surface soil excavation standard (background) were to be excavated and placed as subsurface
fill with a minimum of two feet of clean surface soil cover. The 1990 ROD remedy provided for
reduction of direct contact and inhalation risks for inorganic contaminants in surface soil while
protecting against potential releases to groundwater. The subsurface soil excavation standard
was designed to be protective of groundwater.
This ROD Amendment selects the alternative of covering surface soils above the surface soil
excavation standard and below the subsurface soil excavation standard (see Table 4-2), as
determined using the unmodified TCLP test, with a protective asphaltic concrete surface, rather
than excavating and reburying the soils to a depth greater than two feet. This option provides for
reduction of direct contact and inhalation risks, is protective of groundwater, and reduces the
short-term risks related to excavation and reburial of contaminated surface soil. Figure 8-1
shows the layout of the asphaltic concrete wearing surfaces. The 1990 ROD goal of controlling
surface-related exposures is accomplished more rapidly as compared to the original design
schedule. Applying the asphaltic concrete surface, a wearing surface, avoids the excavation of an
estimated 30,000 cubic yards of contaminated soil and the considerable quantity of airborne and
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other exposures that would be generated. Reducing the amount of excavated soils that must be
handled will allow a better and more focused handling of the remaining high concentrations soils
that must be excavated. Table 8-6 provides an NCP-criteria analysis for this remedy
modification.
8.3.3 Modification of Procedure to Verify Attainment of Soils Treatment Standard
This ROD Amendment modifies the leachate test procedure that is used to confirm the
attainment of treatment standards for soils to be placed in a RCRA-equivalent disposal cell. The
1990 ROD for surface and subsurface soils consists of a numerical limit (Table 4-1) as well as a
specific leachate test procedure (STLC) to measure compliance. To test that soils to be placed in
the RCRA-equivalent disposal cell have met the numerical limit set by the 1990 ROD, deionized
water rather than a citric acid buffer will be used for the leaching solution. The benefits of using
the modified leachate procedure on soils destined for the RCRA-equivalent disposal cell are that
once excavated:
• A smaller volume of soils with inorganic contamination may require fixation prior
to disposal, and
• A smaller volume of soils with organic contamination may require bioremediation
prior to disposal.
Site soils have been shown to be neutral to mildly alkaline. These high pH values, together with
the low amount of decomposable organic material in the soils, particularly compared to that
found in sanitary landfills, indicate that a more site-specific test, i.e., using deionized water
which is neutral, may be more representative of Site conditions.
This modification applies only to testing of soil after excavation or excavation and treatment.
The standard leachate tests will still be used to measure compliance with the subsurface soil
excavation standards that are expressed in terms of leachate (see Table 4-2) and to determine
whether contaminated soils constitute RCRA characteristic hazardous waste. The Area B
treatment standards and the new subsurface soil excavation standards for soils contaminated with
organics, both of which are discussed below, are not expressed in terms of leachate.
Table 8-7 provides an NCP nine criteria analysis for this remedy modification.
This modification does not prevent the WRG from using the more stringent versions of leachate
test procedures, if desired.
8.3.4 Modification of Biotreatment Implementation
The 1990 ROD requires soils contaminated with organics to be excavated and placed in lined
land-treatment cells (RCRA-equivalent cells). Soils were to be treated using natural microbial
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populations, whose effectiveness would be enhanced through the use of nutrients and fertilizers
into the soil. This Amendment broadens the implementation options for bioremediation to allow
treatment in place (in situ), with appropriate monitoring and controls. All bioremediated soils
(with the possible exception of Area B soils discussed below) will be excavated and placed in a
RCRA-equivalent disposal cell.
Bioremediation efforts at the Site since the 1990 ROD was issued indicate that bioremediation
can be controlled to minimize or eliminate leachate formation, the primary reason for the
requirement that the bioremediation be done in lined cells. The bioremediation performed to
date indicates that bioremediation of Site materials is at its most efficient when the moisture
content is low enough to minimize or eliminate leachate formation.
Table 8-8 provides an NCP nine criteria analysis for this alternative treatment option.
8.3.5 Alternative Treatment and Disposal Options for Area B Soils
The 1990 ROD did not specifically address Area B soils. The full extent of contaminated
subsurface soils was delineated during site characterizations under EPA direction in 1994-95.
Area B soils are contaminated with organics and are believed to have been excavated from the
DNAPL Zone and moved to their current location when Roseburg began preparations for new
building construction. The Area B treatment standards are set forth in Table 4-2, and are based
on the newly promulgated LDRs for F032, F034 and F035 listed hazardous waste. All soil in
Area B will be covered with two feet of clean soil. EPA will evaluate in situ bioventing as the
treatment technology for Area B soils. In addition, EPA and will evaluate the results of modeling
and/or other studies to assess the impact of contaminated soils on groundwater in order to ensure
that the cleanup levels achieved by bioventing will be protective of groundwater. If EPA
concludes that the cleanup levels achieved by bioventing will be protective of groundwater, then
Area B soils will remain in place after treatment has been completed. If EPA concludes that the
cleanup levels achieved by bioventing will not be protective of groundwater, then the remedy
will be biotreatment and subsequent disposal in a RCRA-equivalent disposal cell. Area B soils
to be placed in the RCRA-equivalent cell must comply with the 1990 ROD treatment standards
using the modified leachate test described above.
Table 8-9 provides an NCP nine criteria analysis for the bioventing treatment option.
8.3.6 Modified Excavation Standards for Subsurface Soils Contaminated with Organics
EPA has modified the 1990 ROD subsurface soil excavation standards for organics-contaminated
soils outside the DNAPL Zone in order to ensure that they remain protective of groundwater. The
new subsurface soil excavation standards are the same as the Area B treatment standards (see
Table 4-2). As with Area B, EPA will evaluate the results of modeling and/or other studies to
assess the impact of contaminated soils on groundwater. The new subsurface soil excavation
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standards will apply to all soils located outside the DNAPL Zone which are contaminated with
organics (including Area B soils, if bioventing is not successful and the soils are ultimately
excavated). As with Area B, EPA may re-evaluate these excavation standards based on modeling
and/or other studies assessing the impact of contaminated soils on groundwater. Excavated soils
to be placed in the RCRA-equivalent cell must comply with the 1990 ROD treatment standards
using the modified leachate test described above.
8.3.7 RCRA-Equivalent Disposal Cell. Soil Staging and Fixation Area, and Slurry Wall
Construction Zone
8.3.7.1 Designation as CAMUs - EPA designates the RCRA-equivalent disposal cell, the slurry
wall construction zone (consisting of the slurry wall trench and a temporary 60 foot mobile
construction area along the trench) and the soil staging and fixation area, as Corrective Action
Management Units (CAMUs) pursuant to 40 CFR §264.552, as implemented by the State of
California through Title 22, section 66264.552. Accordingly, the CAMU regulation is an ARAR
as discussed in Section 10.2 of this ROD Amendment. Figure 8-2 shows the approximate size
and locations of the soil staging and fixation area, the RCRA-equivalent disposal cell, and the
slurry wall trench. The notice requirements for the ROD Amendment satisfy the public notice
requirements of the CAMU rule.
Without a CAMU, the remedy would require treatment of contaminated soils to satisfy RCRA
LDRs for D004, D007, D037, F032, F034 and F035 wastes prior to placement in the RCRA-
equivalent cell, the soil staging and fixation area and the slurry wall construction zone.
However, placement of remediation wastes into a CAMU does not constitute land disposal of
hazardous wastes and does not trigger the LDR requirements.
The remainder of this section explains how these units satisfy the CAMU requirements and sets
forth the design, operation and closure requirements for each CAMU.
In designating the CAMUs, EPA has considered the criteria set forth in 22 CCR §66264.552.
Table 8-10 provides a seven-criterion analysis for the CAMUs. On the basis of this analysis,
EPA has determined that the CAMUs satisfy the following criteria:
• the CAMUs will facilitate the implementation of a reliable, effective, protective
and cost-effective remedy;
• the management of waste at the designated CAMUs will not create unacceptable
risk to human health or the environment resulting from exposure to hazardous
wastes or hazardous constituents;
• wastes in the CAMUs shall be managed and contained to minimize future release,
to the extent practicable;
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• the CAMUs expedite the timing of remedial activity implementation, when
appropriate and practicable; and
• the CAMUs, to the extent practicable, minimize the land area of the facility upon
which wastes will remain in place after closure of the CAMUs.
The CAMU regulations also provide that the CAMU "shall include uncontaminated areas of the
facility, only if including such areas for the purpose of managing remediation waste is more
protective than management of such wastes at contaminated areas of the facility [22 CCR
§66264.552(c)(3)]. Limited areas are available for locating the RCRA-equivalent cell.
Therefore, the cell will be located in an uncontaminated area. However, locating the cell in an
uncontaminated area is more protective than management of the waste in contaminated areas for
the following reasons:
• The "bottom" of the cell (i.e., soil berms, vadose zone monitoring system, and
bottom liners) can be constructed in a clean area, thereby eliminating worker
exposure to soil contaminants during this phase;
• Contaminated soil will only have to be excavated, or excavated and treated, and
then transported once, thereby minimizing the risks of both worker exposure
during handling as well as worker and residential exposure to contaminated wind-
borne dust; and
• Creation of a single disposal cell in an isolated area of the Site will reduce the
possibility of damage to the cell from ongoing plant operations or future activities
at the site, as well as simplifying long-term maintenance of the cell cover.
EPA also has considered the criteria in subparagraph (6) of 22 CCR §66264.552(c) and
determined that the concerns expressed in such criteria are inappropriate and/or inapplicable to
the Site for the reasons discussed below. The regulations in this subparagraph provide that the
CAMU "shall enable the use, when appropriate, of treatment technologies (including innovative
technologies) to enhance the long-term effectiveness of [remedial] actions by reducing the
toxicity, mobility or volume of wastes that will remain in place after closure of the" CAMU.
Untreated wastes within the slurry wall trench or the RCRA-equivalent disposal cell will be
effectively and reliably contained and immobilized. Wastes will not be left in place after closure
of the soil staging and fixation area or the slurry wall construction zone. Therefore, in
designating these CAMUs, EPA has considered this criteria, and determined that it is not
appropriate for this Site.
8.3.7.2 Design. Operation and Closure Requirements for CAMUs - In accordance with 22 CCR
§66264.552(e), the following section describes the design, operation and closure requirements
applicable to each CAMU:
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RCRA-Eauivalent Disposal Cell - The disposal cell will comply with all ARARs of RCRA and
Title 23 CCR Chapter 15, including groundwater monitoring, leachate control, and closure
requirements. RCRA and Title 23 CCR Chapter 15 requirements are often duplicative . The
more stringent requirements of either Title 22 or Title 23 have been identified as ARARs. Table
8-11 sets forth the requirements that apply to the design, construction, operation and closure of
the RCRA-equivalent cell.
Because EPA has designated the RCRA-equivalent cell as a CAMU, placement of contaminated
soils into the RCRA-equivalent cell will not constitute land disposal of hazardous wastes and
will not require treatment to LDR standards.
Soil Staging and Fixation Area - The soil staging and fixation area has been designated as a
CAMU. The soil staging and fixation area is designed to facilitate the implementation of the
remedy in two respects. First, it is designed to serve as a temporary storage area (one year) for a
small volume (approximately 1500 cubic yards) of contaminated surface soils excavated to
construct the slurry wall. Second, it will serve as a temporary holding area for contaminated
surface soils that will be excavated and placed in the RCRA-equivalent disposal cell. Prior to
placement in the RCRA-equivalent disposal cell, the excavated soils will be tested and will be
fixated, if necessary, to ensure that they meet the 1990 ROD treatment standards using the
modified leachate test described in this ROD Amendment.
The approximate size and location of the soil staging and fixation area is shown in Figure 8-2.
The soil staging and fixation area must satisfy the substantive design, construction, operation and
closure requirements set forth in Table 8-12. These requirements are intended to prevent the
migration of contaminants into adjacent soils and to achieve a level of groundwater protection
equivalent to the prescriptive standards of Title 23 CCR Chapter 15. The soil staging and
fixation area will comply with the Chapter 15 liner, interim cover, precipitation and drainage
control, and other substantive requirements specified in Table 8-12, and will be closed in
accordance with the RCRA clean closure requirements set forth in 40 CFR 264.258, as
implemented through 22 CCR 66264.258.
The requirements identified in Table 8-12 will achieve the level of water quality protection
required by Title 23 CCR Chapter 15. The required interim cover and precipitation and drainage
controls will prevent the generation of leachate by preventing rainwater from infiltrating through
contaminated soil. In the unlikely event that leachate is produced, the required liner will
effectively contain the leachate. Many of the Chapter 15 prescriptive standards, including the
containment structure requirements in Section 2541, are designed for long-term operating
facilities. Since the soil staging and fixation will be closed after approximately one year, these
design features are not necessary to prevent water quality impairment. In addition to the
requirements identified in Table 8-12, the groundwater monitoring plan for the site will protect
water quality by detecting any increases in the levels of groundwater contaminants. Finally, after
approximately one year of operation, the soil staging and fixation area will be closed in
accordance with the RCRA clean closure requirements for waste piles, and all contaminated
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soils, structures and equipment will be excavated, disposed of, or decontaminated and the area
will be covered by an asphalt cap.
In sum, the requirements identified in Table 8-12 for the soil staging and fixation area will
protect groundwater quality to the same extent as the Chapter 15 prescriptive standards and will
therefore comply with Section 2510(b) of Chapter 15. Because many of the Chapter 15
prescriptive standards are designed for long-term operating facilities (30 years plus), requiring
these standards at a temporary facility subject to clean closure would be unreasonably and
unnecessarily burdensome.
Placement of contaminated soil into the soil staging and fixation area will not constitute land
disposal of hazardous wastes because EPA has designated this unit as a CAMU.
Slurry Wall Construction Zone - The slurry wall construction zone (including the slurry wall
trench and the temporary construction area along the slurry wall trench) has been designated as a
CAMU. The approximate size and location of the slurry wall trench is shown in Figure 8-1. The
slurry wall construction zone will consist of the slurry wall trench and a sixty foot construction
area that will follow the construction of the slurry wall. During slurry wall construction,
excavated soils will be temporarily placed on the ground in the slurry wall construction area prior
to being mixed with a slurry compound. The mixture will then be placed into the slurry wall
trench to form the structure of the slurry wall.
Soils excavated for the purpose of constructing the slurry wall will be placed primarily on the TI
Zone side of the slurry wall trench. Consequently, they will generally be located within the
designated containment zone for contaminated media. The soil will be exposed for a very short
period of time. Once excavated and mixed with the slurry compound, the soil will be returned to
the trench. Mixing of the soil with the slurry compound will immobilize any contaminants that
may have been in the soil. The slurry wall construction zone must be managed in accordance
with 40 C.F.R. §264.14(a)-(c), as implemented through CCR §66264.14(a)-(c), requiring, inter
alia, controlled access to the construction zone, 24 hour surveillance, and signs alerting
unauthorized personnel to keep out. Once the soils have been mixed and returned to the slurry
wall trench, all contaminated soils must be excavated from the construction area in accordance
with the clean closure requirements set forth in 40 C.F.R. §264.258(a), as implemented through
CCR §66264.258 (a). The majority of the soils being handled in construction of the slurry wall
are either not contaminated or contain very low levels of contamination. The low levels and
reduced quantities of contamination, brief exposure period, placement primarily within the TI
Zone, 24 hour surveillance and other security precautions, and clean closure requirements will
ensure that there is no unacceptable risk to human health and the environment.
Temporary placement of remediation wastes in the slurry wall construction zone and placement
of remediation wastes into the slurry wall trench to form the structure of the slurry wall will not
constitute land disposal of hazardous waste because EPA has designated the slurry wall
construction zone as a CAMU. Although the slurry wall construction zone has been designated a
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CAMU, it will still be subject to the applicable or relevant and appropriate provisions of Chapter
15. Section 251 l(d) of Chapter 15 exempts CERCLA cleanup actions from Chapter 15, provided
that remedial actions intended to contain wastes at the place of release shall implement
applicable provisions of Chapter 15 to the extent feasible. For the reasons explained above, EPA
has concluded that requiring the slurry wall construction zone to comply with the Chapter 15
prescriptive requirements, including the liner requirements, would be unnecessarily and
unreasonably burdensome, and would therefore not be feasible. Moreover, the requirements for
the slurry wall construction zone will provide a level of groundwater protection equivalent to the
Chapter 15 prescriptive requirements and will therefore comply with §2510 (b) of Chapter 15. <
ARARs for the construction of the slurry wall itself are set forth in Table 8-4. Because the slurry
wall containment system is not a "waste management unit" as that term is defined in Chapter 15,
Chapter 15 action specific ARARs are relevant and appropriate rather than applicable.
8.3.8 Institutional Controls
The 1990 ROD required excavation of contaminated soil, extraction of contaminated
groundwater, and treatment to the standards specified in the ROD. However, this ROD
Amendment provides for the containment of contaminated soils and groundwater in the DNAPL
Zone. As a result, institutional controls are added to the remedy to assure protectiveness of the
remedy.
The institutional controls are described in Section 7.3. The primary purpose of these controls is
to prevent exposure to contaminated soils and groundwater that will remain during and after
remediation.
Institutional controls will also protect the integrity of the remedy through appropriate
prohibitions on activities that would disturb soil or any cap placed on soil, or activities that
would breach the slurry wall or disturb the RCRA-equivalent disposal cell. One element of these
controls will be a soils handling plan. The soils handling plan will be developed and approved
by EPA to address instances where building decommissioning/construction activities, routine
maintenance, or other ground intrusive activities on site may occur.
8.3.9 Ditch Sediments
In the 1990 ROD, the selected remedy for contaminated sediments; sediments in Beaughton
Creek near the NPDES discharge point; and site drainage sediments was excavation by dredging
followed by treatment and disposal. This ROD Amendment modifies requirements for
contaminated sediment within drainage ditches discharging Site runoff into Beaughton Creek.
Rather than excavation, treatment, and disposal, the ditch sediments will be allowed to continue
to degrade naturally to a level below the 1990 ROD sediment excavation standards (see Table
4-1 and 4-2).
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Post 1990 ROD sediment sampling has found only two ditch segments with consituent
concentrations above the sediment excavation standards (Table 4-1). However, and more
importantly, these concentrations are only slightly above excavation standard concentrations.
Additionally, further comparative analysis of excavation versus natural flushing indicates more
potential adverse environmental impact from disturbing the sediments during excavation than
from natural flushing (TRC 1996a). Potential adverse impacts include human contact during
excavation and increased releases to surface water.
. Post 1990 ROD monitoring of Beaughton Creek indicates natural flushing and attenuation of
contaminated sediments has occurred. This natural attenuation is expected to continue with no
adverse environmental impact and is expected to result in concentrations of contaminants of
concern dropping to below sediment excavation standards (TRC 1996a). Consequently this
ROD Amendment selects natural attenuation as the remedy for ditch sediments, provided that the
contaminants degrade naturally to a level at or below the sediment cleanup standards set forth in
Table 4-2 and that the contaminated sediments are not disturbed. However, stream sediments
will continue to be monitored, the areas of concern in the stream will be posted with cautionary
signs, and the discharge and surface water runoff from the site will continue to be monitored in
order to ensure protectiveness.
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9.0 SELECTED REMEDY
The following sections describe the modifications to the 1990 ROD, including the selected
alternative for the DNAPL Zone and additional enhancements, modifications, and containment
measures. Figure 8-1 shows the locations of all the remedy components for the Site. Table 4-2
sets forth the cleanup standards for the modified remedy. Table 8-4 summarizes the ARARs
triggered by the modified remedy in addition to those identified in the 1990 ROD and reproduced
in Tables 8-2 and 8-3.
9.1 Cleanup Standards for the DNAPL Zone
None of the alternatives evaluated by EPA in the FFS were found to be effective and
implementable for the cleanup of groundwater within the DNAPL Zone to 1990 ROD standards.
Therefore, EPA concluded that it is not possible to achieve the 1990 ROD cleanup standards for
groundwater within the DNAPL Zone. EPA is therefore waiving the groundwater cleanup
standards within the DNAPL Zone based on a determination that attainment of these standards is
technically impracticable from an engineering perspective, and that the slurry wall can effectively
contain the contamination left in place. Page two of Table 4-2 sets forth the groundwater cleanup
standards which will be waived in the DNAPL Zone.
Within the DNAPL Zone, EPA is revising the 1990 ROD cleanup strategy for groundwater and
subsurface soils to ensure that the remedy remains protective of human health and the
environment. The revisions include the following elements:
• Contain groundwater and DNAPLs to prevent their migration
• Prevent ingestion of contaminated groundwater
• Prevent direct contact with contaminated subsurface soils and seeps.
The cleanup standards defined in this ROD Amendment are subject to re-evaluation with respect
to effectiveness in protecting human health and the environment at the 5-year review period.
9.2 Selected Remedial Action for the DNAPL Zone
EPA's selected remedy for groundwater and subsurface soil within the DNAPL Zone is
Alternative 3, Additional Containment and Institutional Controls, provided that the institutional
controls can be effectively implemented. The selected remedy requires the construction of a
slurry wall around the DNAPL Zone in order to enhance groundwater restoration outside the
DNAPL Zone and to contain the contaminated groundwater within the DNAPL Zone. Table 8-4
sets forth the requirements for the slurry wall containment system.
An inward gradient shall be established by extracting groundwater within the slurry wall.
Contaminant migration outside of and below the DNAPL Zone shall be detected by a monitoring
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system and shall be corrected. Monitoring data shall be carefully evaluated, and existing Site
groundwater transport models on the behavior of the slurry wall and containment area shall be
compared on an ongoing basis to the actual groundwater data. Other information on containment
performance shall be regularly reviewed to determine if evidence exists of containment zone
failure such that contaminants are migrating or suspected to be migrating from the zone. Where
failure is suspected, measures shall be promptly taken to confirm containment zone failure. Once
substantially confirmed, immediate corrective actions to control migration of pollutants from
within the zone shall be initiated where contaminants are migrating or suspected to be migrating
to groundwater areas which contain constituents of concern at levels less that present in the
migrating groundwater. Additional measures shall be developed, if necessary, to address
containment zone failure. The monitoring program shall require that a report of all actions be
filed with EPA and the State after discovery of any suspected containment system failure or of
taking any corrective action with respect to the containment system.
Pooling of DNAPLs within the zone itself shall be detected by a monitoring system and shall be
extracted. The Roseburg excavation shall be re-graded to improve surface drainage and reduce
infiltration and shall be covered with a minimum of two feet of clean backfill. Institutional
controls shall be implemented to prevent future exposures to contaminants in the DNAPL Zone
and to protect the integrity of the remedy.
These controls shall include:
a. limiting future land uses to appropriate industrial uses (and prohibiting other
uses);
b. restricting access to and use of contaminated groundwater;
c. prohibiting activities that would disturb the integrity of the remedy, including
appropriate prohibitions on activities that would disturb the soil and/or any cap
placed upon such soil;
d. requiring appropriate handling of excavated materials;
e. providing for appropriate notice (in land records and otherwise) that hazardous
wastes remain on site; and
f. prohibiting other activities that could cause a potential threat to human health or
the environment.
EPA estimates that it will take an additional one to two years to implement this remedy. The
selected remedy protects human health and the environment and achieves the cleanup objectives
of containing contaminated groundwater in the DNAPL Zone, preventing ingestion of
contaminated groundwater, and preventing direct contact with contaminated subsurface soils and
seeps.
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9.3 Selected Remedy Enhancements
To enhance the 1990 ROD remedy EPA has selected the following modifications to the
groundwater and soils remedies as well as these additional containment measures.
Modification for Disposal of Treated Water
• Addition of the option of direct discharge to Beaughton Creek for treated water
based on NCRWQCB regulatory actions to require treatment of water to best
practicable methods. The preferred disposal option continues to be reuse on
Roseburg's log decks as described in the 1990 ROD. Reuse on the log decks
would reduce water diversions from Beaughton Creek, which is water-limited
during the dry season. Treated water discharged to Beaughton Creek must meet
the standards set forth in Table 4-2.
Additional Modifications to Soils Remedies
• Surface Soils Containing Inorganic Concentrations above Background and below
the 1990 ROD Subsurface Soil Excavation Standard - Covering these soils with a
protective asphaltic concrete surface, rather than excavating and reburying the
soils on-site at a depth greater than two feet. This modification will provide equal
long-term protectiveness while minimizing short-term risks associated with
excavation and handling of soils. All soils outside the DNAPL Zone exceeding
the subsurface soil excavation standard set forth in Table 4-2 for any contaminant
(using the standard leachale test) will still be excavated. It should be noted that
the surface and subsurface soil excavation standards for inorganics have not
changed.
• Modification of Procedure to Verify Attainment of Soils Treatment Standard -
Modifying the 1990 ROD treatment standard for soils to be placed in the lined
disposal cells (equivalent to Resource Conservation and Recovery Act [RCRA]
disposal cells) by modifying the leachate test procedure. The new test will use
deionized water rather than a citric acid buffer for the leaching solution. The test
will be used to demonstrate that soils have met the 1990 ROD numerical
treatment standards for soils placed in the RCRA cell. These standards are
reproduced in Table 4-2. Because testing has shown that Site soils are not acidic,
deionized water, which is neutral, may be more representative of Site conditions.
Additionally, as this modification will apply only to soils to be placed in the
RCRA-equivalent cell, there is no increased threat to humans or groundwater
• Modification of Biotreatment Implementation - Broadening the implementation
options for biotreatment to allow treatment in place (in situ), with appropriate
monitoring and controls. However, all biotreated soils (with possible exception of
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Area B soils as explained below) will be excavated and placed in a lined RCRA-
equivalent disposal cell.
• Alternative Treatment and Disposal Options for Area B Soils - Area B soils are
contaminated with organics and are believed to have been excavated from the
DNAPL Zone and moved to their current location when Roseburg began
preparations for new building construction. EPA has selected treatment standards
for Area B (see Table 4-2) based on groundwater protection concerns. In
addition, Area B soils will be covered by two feet of clean soil. EPA will evaluate
in situ bioventing as the treatment technology for Area B soils. EPA will also
evaluate the results of modeling and/or other studies to assess the impact of
contaminated soils on groundwater in order to ensure that the cleanup levels
achieved by bioventing will be protective of groundwater. If EPA concludes that
the cleanup levels achieved by bioventing will be protective of groundwater, then
Area B soils will remain in place after treatment has been completed. If EPA
concludes that the cleanup levels achieved by bioventing will not be protective of
groundwater, then the remedy will be biotreatment and subsequent disposal in a
RCRA-equivalent disposal cell. Area B soils to be placed in the
RCRA-equivalent cell must comply with the 1990 ROD treatment standards,
reproduced in Table 4-2, using the modified leachate test described above.
• Modified Excavation Standards for Subsurface Soils Contaminated with Organics -
EPA has modified the 1990 ROD subsurface soil excavation standards for
organics-contaminated soils outside the DNAPL Zone in order to ensure that they
remain protective of groundwater (see Table 4-2). The new subsurface soil
excavation standards are the same as the Area B treatment standards and will
apply to all soils located outside the DNAPL Zone which are contaminated with
organics (including Area B soils, if bioventing is not successful and the soils are
ultimately excavated). As with Area B, EPA and will evaluate the results of
modeling and/or other studies to assess the impact of contaminated soils on
groundwater. In accordance with the remedy modifications described above,
subsurface soils within the DNAPL Zone will not be excavated. Excavated soils
to be placed in the RCRA-equivalent cell must comply with the 1990 ROD
treatment standards, reproduced in Table 4-2, using the modified leachate test
described above.
• Designation of Disposal Cell and Soil Staging and Fixation Area for Soils - EPA
designates three features of the remedy as RCRA Corrective Action Management
Units (CAMUs): The RCRA-equivalent disposal cell, the soil staging and
fixation area, and the slurry wall construction zone. These CAMUs must comply
with the requirements set forth in sections 8.3.7 and 10.2 of this ROD
Amendment and in Tables 8-11 and 8-12. Neither placement of remediation
wastes into the RCRA-equivalent disposal cell, nor temporary placement of soils
in the soil staging and fixation area and the slurry wall construction zone, nor
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incorporation of contaminated soils into the slurry wall trench will constitute land
disposal of hazardous wastes.
Modification for Handling of Soils Uncovered during Operation and Maintenance
• Handling of Soils during Operation and Maintenance - A soils handling plan will
be developed and approved by EPA to address instances where building
decommissioning/construction activities, routine maintenance, or other ground
intrusive activities on site may occur.
9.4 Selection of Institutional Controls
This ROD Amendment modifies the remedy for soil and groundwater within the DNAPL Zone.
Subsurface soil within the DNAPL Zone will be left in place rather than excavated.
Groundwater within the DNAPL Zone will be contained rather than remediated. In order to
prevent exposure to contaminated soil and groundwater, and to preserve the overall integrity of
the remedy (including the cap, slurry wall and RCRA-equivalent disposal cell). The institutional
controls described in Section 9.2 above shall be implemented.
9.5 Modification of Remedy for Ditch Sediments
This ROD Amendment modifies requirements for excavation, treatment, and disposal of
contaminated sediments within drainage ditches discharging Site runoff into Beaughton Creek.
The ditch sediments will be allowed to continue to degrade naturally to the standards specified in
Table 4-2, provided that contaminated ditch sediments are not disturbed. However, stream
sediments will continue to be monitored and the areas of concern in the stream will be posted
with cautionary signs to notify the public of any contamination that may have been detected. In
addition, the discharge and surface water runoff from the site will continue to be monitored to
ensure protectiveness.
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10.0 STATUTORY DETERMINATION
10.1 Protection of Human Health and the Environment
The selected remedy protects human health and the environment through excavation, treatment
or fixation, as necessary, and then containment of contaminated soil in a RCRA-equivalent
disposal cell, through in situ bioventing for Area B soils, through capping of surface soils
beneath an asphaltic concrete surface, by extraction and treatment of groundwater, and by
containment of groundwater and subsurface soils contaminated with DNAPLs within a slurry
wall. Excavation of subsurface soils, and excavation or capping of surface soils to achieve
cleanup standards will ensure that residual contamination does not pose unacceptable risk to
workers at the site or neighboring residents.
Deed restrictions will prevent future uses of the site (such as residential development or
installation of drinking water wells) that would result in unacceptable levels of exposure to
contaminated soil or groundwater. There are no short-term threats associated with the selected
remedy that cannot be readily controlled. In addition, no adverse cross-media impacts are
expected from the remedy.
The primary long-term risk posed by the RCRA-equivalent disposal cell and the DNAPL Zone is
direct exposure (i.e., direct contact) the contaminated material contained in these portions of the
remedy. Exposure is unlikely, however, because of the cover that will be placed on the disposal
cell and the asphaltic concrete surface that will placed over surface soils.
The potential for exposure due to migration of contaminants through a leaking liner in the
disposal cell into groundwater that is used for water supply is exceedingly small. Furthermore,
soil will be placed in the cell in a relatively dry state (i.e., very low moisture content and no free
liquids). The disposal cell design, monitoring systems and maintenance requirements are
expected to prevent conditions that would allow leaks.
The potential for exposure due to migration of contaminants from the DNAPL Zone into
groundwater that is used for water supply is small. Contaminants will be contained laterally by
the slurry wall and the hydraulic gradient induced by pumping. Contaminants will be contained
vertically by the OCA, which is the confining unit separating the contaminated upper aquifer
from the uncontaminated lower aquifer. In addition, protection of the lower aquifer will be
assured through a groundwater monitoring program.
10.2 Compliance with ARARs
Remedial actions selected under CERCLA must comply with all Applicable or Relevant and
Appropriate Requirements ("ARARs") under federal environmental law or, where more stringent
than the federal requirements, state or state subdivision environmental or facility siting laws.
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Where a State is delegated authority to enforce a federal statute, such as RCRA, the delegated
portions of the statute are considered to be a federal ARAR unless the State law is broader or
more stringent than the federal law.
ARARs are generally characterized as follows: (1) chemical-specific requirements; (2) action-
specific requirements; and (3) location-specific requirements. Where no ARAR exists for a given
chemical, action or location, EPA may consider non-promulgated federal or state advisories and
guidances as To Be Considered criteria ("TBC"). Although consideration of a TBC is not
required, if standards are selected based on TBCs, those standards are legally enforceable as if
the TBC were an ARAR.
Chemical-specific ARARs are risk-based cleanup standards or methodologies which, when
applied to site-specific conditions, result in the development of cleanup standards for
contaminants of concern.
Location-specific ARARs are restrictions placed on concentrations of hazardous substances or
the conduct of activities because of the special locations, which have important geographical,
biological or cultural features. Examples of special locations include wetlands, flood plains,
sensitive ecosystems and seismic areas.
Action-specific ARARs are technology-based or activity-based requirements or limitations on
actions to be taken to handle hazardous wastes. They are triggered by the particular remedial
activities selected to accomplish a remedy.
The ARARs adopted in the ROD are presented in Tables 8-2 and 8-3. These ARARs were
"frozen" as of the date of the ROD and will only be re-opened in this ROD Amendment to the
extent that (i) modifications to the remedy require a waiver of those ARARs or present new
remedial activities that require the adoption of additional action specific ARARs; or (ii) newly
promulgated or modified requirements are necessary to ensure the protectiveness of the selected
remedy. See 40 CFR §300.430(0(1 )(ii)(B); 55 Federal Register 8747, 8757-8758 (March 8,
1990).
The ROD Amendment modifies both the groundwater remedy and the soils remedy. The ARARs
implications of these modifications are discussed below and are also summarized in Table 8-4.
Waiver of Groundwater Cleanup ARARs
In this ROD Amendment, EPA concludes that it is technically impracticable from an engineering
perspective to achieve the ROD cleanup standards for groundwater within the DNAPL Zone.
The revised groundwater remedy provides for the construction of a slurry wall containment
system (including hydraulic gradients induced by pumping) in order to contain the contaminated
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groundwater in the DNAPL Zone. Groundwater outside of the DNAPL Zone will be remediated
to the ROD groundwater cleanup standards.
Selection of a containment remedy for groundwater within the DNAPL Zone requires the waiver
of the groundwater cleanup standards set forth in the ROD on the basis of technical
impracticability (TI). The factual basis for the TI waiver is set forth in the TI Evaluation
Summary in the FFS.
Page 2 of Table 4-2 sets forth the groundwater ARARs selected in the ROD, which will be
waived for the groundwater contained in the DNAPL Zone.
North Coast Regional Water Quality Control Board (NCRWQCB) Action Specific ARARs
for the Slurry Wall Containment System
Although EPA has regarded the slurry wall as a necessary design element for groundwater
restoration outside of the DNAPL Zone, it was not an explicit element of the remedial action
selected in the ROD. Therefore, action-specific ARARs for the slurry wall have been identified
in Table 8-4.
The slurry wall containment system is designed to protect the lower aquifer. The requirements
cited in Table 8-4 apply to ensure that the slurry wall containment system effectively precludes
the constituents of concern from reaching the lower aquifer, which has been designated for
municipal and domestic water supply. In addition, certain provisions of Title 23, Chapter 15 of
the California Code of Regulations set forth engineering and construction requirements for the
vertical and horizontal containment of wastes in place and address material compatibility
requirements between site contaminants and slurry wall construction materials. Because the
slurry wall containment system is not a "waste management unit," the substantive requirements
of the sections of Chapter 15 cited in Table 8-4 are not applicable, but are "relevant and
appropriate" to the implementation of the slurry wall containment system. The substantive
requirements of the Chapter 15 provisions and NCRWQCB requirements identified in Table 8-4
are ARARs for the modified remedial action.
Resource Conservation and Recovery Act (RCRA) Requirements for Management of
Excavated Soil and Contaminated Groundwater and for the Slurry Wall Construction
Action specific ARARs relating to the management of hazardous wastes are applicable to the
excavation of contaminated soils. This includes excavation of surface or subsurface soil to be
placed in the RCRA-equivalent disposal cell and excavation of soil for the construction of the
slurry wall containment system and for the installation of a gravel drainage trench and pipe drain,
which would operate in conjunction with the slurry wall excavation system. This is because some
of the surface or subsurface soil to be excavated may exhibit a hazardous characteristic or may
contain F032, F034 and/or F035 listed hazardous wastes, or both. These listed wastes, which are
related to wood preserving operations, were listed after the date of the ROD. (See 57 Federal
Register §61492, December 30, 1992). This ROD Amendment recognizes this new listing as well
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as the new LDRs for these listed wastes in its analysis of RCRA ARARs because EPA has
concluded that this is necessary to ensure that the remedy is protective of human health and the
environment. All excavated soil which contains these listed hazardous wastes or which exhibit a
hazardous characteristic must be handled in accordance with all RCRA requirements relating to
the management of hazardous wastes. Likewise, all contaminated groundwater must be handled
in accordance with all RCRA requirements for the management of hazardous wastes if the water
exhibits a hazardous characteristic or contains hazardous waste.
Once excavated, contaminated soils will be treated and disposed of in the RCRA-equivalent
disposal cell in accordance with this ROD Amendment, except to the extent that they are
temporarily placed in the slurry wall construction area or the soil staging and fixation area, or are
returned to the slurry wall trench to form the structure of the slurry wall. These activities would
ordinarily be subject to the RCRA Land Disposal Restrictions (LDRs), including the newly
promulgated LDRs for F032, F034 and F035 listed hazardous wastes. (See 62 Fed. Reg. §25998,
May 12, 1997). Soils temporarily placed in the slurry wall construction area or in the soil staging
and fixation area, and soils returned to the slurry wall trench to form the structure of the slurry
wall will not be subject to the RCRA LDRs because this ROD Amendment designates the slurry
wall construction zone (including the trench and the construction area) and the soil staging and
fixation area as Corrective Action Management Units (CAMUs) pursuant to 40 CFR §264.552,
as implemented by the State of California through Title 22, Section 66264.552 of the California
Code of Regulations (CCR), Soil placed in the RCRA-equivalent disposal cell, in accordance
with this ROD Amendment, are also not subject to the LDR's because EPA has designated the
RCRA-equivalent disposal cell as a CAMU. Section 8.3.7 of the ROD Amendment sets forth the
CAMU designation.
Construction of the slurry wall will consist of mixing the excavated media with a slurry
compound and replacing the mixture into the original excavation where it will harden and create
an underground barrier to contain DNAPLs and contaminated groundwater in the shallow
aquifer. Excavated soils will be placed temporarily on the ground adjacent to the trench prior to
mixing and will be managed in accordance with the requirements specified in Section 8.3.7 of the
ROD Amendment. The requirements for the construction of the slurry wall itself are set forth in
Table 8-4.
Finally, after the backfill material is placed, a permanent cap will be placed on the ground surface
of the slurry wall and the trench. No buildings or other permanent structures will be placed on
top of the slurry wall structure that will impair the integrity or proper functioning of the wall. In
the event that future construction results in the excavation of soils which exhibit a hazardous
characteristic or contain F032, F034 or F035 hazardous wastes, the excavated soils will be
managed in accordance with RCRA requirements.
Clean Water Act Storm Water Requirements
If construction activities at the site (including construction of the slurry wall containment system
and the RCRA-equivalent disposal cell) involve soil disturbances, the discharges of storm water
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runoff associated with this construction activity will be subject to the substantive requirements of
the General NPDES Permit for Storm Water Discharges Associated with Construction Activity,
Order No. 92-08-DWQ, issued by the SWRCB pursuant to its delegated authority under the
federal Clean Water Act (Federal Water Pollution Control Act) and regulations promulgated
thereunder. In addition, the substantive portions of the General NPDES Permit for Discharges of
Stormwater Associated with Industrial Activities Excluding Construction Activities, Order No.
97-03--DWQ, are action specific ARARs for industrial activities related to the remedy, such as
equipment operation, and for stormwater runoff flowing over contaminated surface soils at the
site.
NCRWQCB Requirements for Discharge of Treated Effluent to Beaughton Creek
The ROD prohibited the direct discharge of treated groundwater to Beaughton Creek, and
therefore did not set treatment standards for such discharges. The discharge options, however,
now include the discharge of treated water to Beaughton Creek. The ARARs for this discharge
are the chemical and action specific substantive requirements of the federal Clean Water Act
National Pollutant Discharge Elimination System (NPDES) program. This program has been
delegated to each of the Regional Water Quality Control Boards (RWQCBs) in California. These
chemical and action specific requirements are set forth in the substantive portions of the Waste
Discharge Requirements (WDRs) issued in 1993 by the NCRWQCB. The substantive portions of
Cease and Desist Order (No. 93-87) and Waste Discharge Requirements (Order No. 93-88) allow
discharges to Beaughton Creek on a temporary basis, provided that these discharges are
eliminated over time as the cleanup progresses. The water treatment system must be operated in
a manner that minimizes discharges to Beaughton Creek by preliminarily considering use of the
other disposal options allowed by the ROD, leaving Beaughton Creek as a last and least favored
option. The chemical specific discharge limitations are reproduced in Table 8-4.
Groundwater Monitoring Requirements
EPA has published technical guidance on the development and implementation of groundwater
monitoring programs in a document entitled "RCRA Ground Water Monitoring: Draft Technical
Guidance," Nov. 1992 (EPA/530-R-93-001). While these requirements have not been
promulgated as enforceable regulations and are therefore not ARARs, EPA has determined that
they will be applied in developing a comprehensive monitoring program for the site.
Requirements for the RCRA Corrective Action Management Units (CAMUs)
The RCRA-equivalent disposal cell must satisfy the substantive RCRA and Chapter 15 landfill
requirements set forth in Table 8-11 of the ROD Amendment, including the specified design
standards for the liner system, the leachate collection and removal systems, leak detection
systems and the final cover. In addition, state and federal regulations require that the foundation
be placed on a foundation base capable of providing adequate support to prevent liner failure.
RCRA requirements also address construction of run-on control and run-off management
systems, management of collection and holding facilities for such systems, and preparation of a
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closure and post-closure plan. In addition, U.S. EPA 1987 Technical Guidance on Bottom Liners
and U.S. EPA 1989 Technical Guidance on Covers should be considered in the design and
construction of the disposal cell.
During construction, the landfill liner must be inspected to insure that it meets the state and
federal liner standards. RCRA also requires the maintenance of security from the time that
contaminated materials are placed in the landfill until the cover is in place. Upon closure of the
landfill, RCRA requirements with respect to maintenance and care of the landfill and detection
and evaluation monitoring (including monitoring of soil pore liquids) must be complied with in
order to insure that the landfill does not release any contaminants to groundwater.
The soil staging and fixation area must satisfy the requirements for waste piles set forth in Table 8-
12 of the ROD Amendment, including the specified standards for the liner, the interim cover, and
the precipitation and drainage controls. It must also meet the specified construction, seismic
design, and security requirements. Upon closure, the soil staging and fixation area must comply
with the RCRA clean closure requirements set forth in Table 8-12.
The requirements for the slurry wall construction zone CAMU are described in Section 8.3.7, and
are discussed above in connection with the RCRA requirements for construction of the slurry wall
and the management of excavated soils.
10.3 Cost Effectiveness
Cost-effectiveness is determined by evaluating three of the balancing criteria (long-term
effectiveness and permanence; reduction of toxicity, mobility or volume through treatment; and
short-term effectiveness) to determine overall effectiveness. Overall effectiveness is then
compared to cost to ensure that the remedy is cost-effective.
The selected remedy for the DNAPL Zone, the baseline slurry wall containment of DNAPL
within the Target Area (Alternative 1) and additional containment for the Roseburg Excavation
and institutional controls (Alternative 3), provides reliable containment assuming continual
maintenance of the wall and mechanical systems.
The selected remedy would provide reduction in mobility of DNAPL and aqueous phase
contaminants within the Target Area by use of a slurry wall containment system and of
contaminated soils since the Roseburg Excavation would be covered with clean soil.
The selected remedy has high short-term effectiveness since the risks posed to the community or
site workers during implementation are low, with some short-term risks in connection with the
transportation of soil and with the regrading and covering of the Roseburg Excavation. No short-
term risks are involved in the implementation of the proposed institutional controls.
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The cost of the selected remedy assumes as baseline the cost of the proposed slurry wall
containment and hydraulic control system ($11 million) plus costs related to containment and
institutional controls for Alternative 3 ($1.3 million). The selection of this remedy will have
short-term effectiveness and long-term effectiveness, and will provide a reduction in the mobility
of DNAPL contamination, while costing less than other options.
The remedy presented in Section 9 also includes some enhancements to the remedy presented in
the 1990 ROD. These include in situ bioremediation, the addition of an asphaltic concrete cover
over some soils containing inorganics above background but below the subsurface soil
excavation standard, and the alternative treatment option for contaminated soil in Area B. By
reducing the amount of soil handling required, in situ bioremediation will reduce the short-term
exposure risks associated with moving and transporting this soil. Since in situ bioremediation is
expected to achieve the required level of toxicity reduction, it meets the goal of long-term
effectiveness. Finally, in situ bioremediation will provide a reduction in the toxicity and volume
of contaminated soil. This modification has lower short-term exposure risks, and will result in
the reduction of the toxicity and volume of these contaminated soils, while costing less than the
option it replaces, due to the elimination of the initial excavation step and the need for a lined
treatment cell.
The addition of an asphaltic concrete cover over some soils contaminated with low levels of
inorganics (i.e., above background but below the 1990 ROD subsurface soil excavation
standards), will reduce the direct contact and inhalation risks in surface soil. It will also reduce
the mobility of these contaminants by limiting the amount of water that comes into contact with
them, thereby decreasing the potential for further groundwater degradation. The addition of this
modification has low short term risks, and will result in the reduction of the mobility of the
contaminants in these soils, while costing about the same as the option it replaces.
The alternative treatment option for soil in Area B provides a lower risk to site workers since
little or no excavation of soils is required for in situ treatment. Since in situ bioremediation is
expected to achieve the required level of toxicity reduction, this meets the goal of long-term
effectiveness. Reduction of mobility, toxicity, and volume of organic contaminants will occur
through in situ treatment. If the Area B soils can not be adequately treated to meet the treatment
standards set forth in Table 4-2 through in situ treatment, and if modeling and/or other studies
show that the cleanup levels .achieved by bioventing are not protective of groundwater, then
reduction of mobility, toxicity, and volume will occur by excavation and disposal in the RCRA-
equivalent cell. Elimination of excavation and the lined treatment cells will significantly reduce
treatment and materials handling costs. The addition of this modification has low short-term
exposure risks, is expected to meet the goal of long-term effectiveness, and will result in the
reduction of the toxicity and volume of these contaminated soils, while costing less than the
option it replaces, due to the elimination of the initial excavation step, the need for a lined
treatment cell and the need for disposal in a RCRA-equivalent disposal cell for all of the soil that
is successfully treated in situ.
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10.4 Utilization of Permanent Solutions and Alternative Treatment Technologies to the
Maximum Extent Practicable
EPA has determined that the selected remedy for the DNAPL Zone and soils outside the DNAPL
Zone (including Area B), in conjunction with the 1990 ROD remedy for groundwater outside of
the slurry wall, represents the maximum extent to which permanent solutions and treatment
technologies can be used in a cost-effective manner for soils and groundwater at the Baxter site.
Of the alternatives evaluated, EPA has determined that the selected remedy provides the best
balance of tradeoffs in terms of the nine criteria used for remedy selection. In particular, this
remedy represents the best balance among long-term effectiveness and permanence, reduction of
toxicity, mobility or volume through treatment, implementability, short-term effectiveness, and
cost.
Although the selected remedy for the DNAPL Zone does not result in the treatment of
contaminants in subsurface soil, in situ biotreatment will. In addition, DNAPLs will degrade
over lime. The selected remedy is comparable in terms of long-term effectiveness to excavation
and treatment alternatives, in part because disposal of excavated wastes also requires long-term
containment in the RCRA equivalent cell and long-term monitoring of the cell. Additionally,
excavation in the DNAPL Zone would be expected to remove only as much as 40 percent of the
DNAPL contaminated soils. The selected remedy ranks higher in terms of short-term
effectiveness and will require less time to implement.
The in situ biotreatment of soils outside the DNAPL Zone, including Area B, will maximize the
use of alternative treatment options while remaining protective of groundwater.
10.5 Preference for Treatment as a Principal Element
The selected remedy uses treatment as a principal element for soils and groundwater outside of
the slurry wall (1990 ROD remedy). The remedy for the DNAPL Zone uses containment, rather
than treatment, to address the threats posed by contaminated subsurface soil and groundwater.
Excavation and treatment of DNAPL-contaminated subsurface soil inside the slurry wall cannot
remove more than an estimated 40 percent of the contaminated material, nor is it cost effective.
Therefore, containment within the slurry wall, combined with in situ bioremediation for
contaminated soils outside of the TI Zone, will be effective in eliminating the threat of direct
exposure and reliably reducing mobility.
The modified remedy for the Area B soils uses in situ bioremediation to treat the contamination.
However, if the Area B soils can not be adequately treated through 'in situ treatment, reduction of
mobility, toxicity, and volume will occur by excavation and disposal in the RCRA-equivalent
cell.
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11.0 DOCUMENTATION OF SIGNIFICANT CHANGES
The treatment standard for non-carcinogenic PAHs, which was incorrectly listed as 0.15 ppm in
the Proposed Plan and in parts of the 1990 ROD, has been corrected. The correct number (based
on page 11-1 of the 1990 ROD) is 1 ppm.
In addition, the aquifer cleanup and groundwater treatment standards for tetrachlorophenol,
which was inadvertently omitted from the 1990 ROD, has been added to Table 4-2. The 1.1 ppm
standard is a risk based number. This standard is based on accepable exposure levels for
systemic toxicants. The ROD Amendment modifies the remedy in two additional respects which
were not discussed in the Proposed Plan. First, as explained in Sections 8.3.5 and 8.3.6, the
ROD Amendment sets treatment standards for Area B soil, established new subsurface soil
excavation standards for organic-contaminated soil outside the DNAPL Zone, and requires
modeling and/or other studies to assess the impact of these organic-contaminated soils on
groundwater. Second, as explained in Section 8.3.8, the ROD Amendment allows ditch
sediments to degrade naturally to the 1990 ROD standards rather than requiring excavation. This
modification reflects the fact that natural flushing and attenuation has successfully reduced
contaminant concentrations in ditch sediments.
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12.0 REFERENCES
Bechtel 1997. Final Focused Feasibility Study and Evaluation of Technical Impracticability, J.H.
Baxter Superfund Site, Weed, California. Prepared for U.S. Environmental Protection Agency.
May 1997.
CDM (Camp, Dresser, McKee, Inc.) 1989. Remedial Investigation Report. Prepared for U.S.
Environmental Protection Agency, Office of Waste Program Enforcement. January, 1989.
Cohen & Mercer. 1993. DNAPL Site Evaluation. Robert M. Cohen and James L. Mercer.
EPA/600/R93/022, February 1993.
ENVIRON (Environ Corporation), 1995. Technical Memorandum Evaluation of ROD Remedy
Baxter Superfund Site. March 1995.
Environmental Solutions 1995a. Draft Preliminary (30%) Remedial Design Report Ground
Water/Slurry Wall Remediation System. Prepared for Weed Remediation Group. August 1995.
Environmental Solutions 1995b. Draft Prefmal (90%) Remedial Design Report Surface Soils
Area B and Ditch Sediments. Prepared for Weed Remediation Group. September 1995.
Environmental Solutions 1996a. Results of teachability Testing on Surface Soils, Technical
Memorandum, J.H. Baxter Superfund Site. Prepared for Weed Remediation Group. February
1996.
Environmental Solutions 1996b. Technical Memorandum, Proposed Interim Remedial
Measures, Roseburg Excavation Area, J.H. Baxter Superfund Site. Prepared for Weed
Remediation Group. 1996.
EPA 1990. J. H. Baxter Superfund Site, Weed, California Record of Decision. September 25,
1990.
EPA 1991. Administrative Order and Scope of Work for the Remedial Design and Action at the
J.H. Baxter Site, Weed, Siskiyou County, California. August 1991.
EPA 1993. Guidance for Evaluating the Technical Impracticability of Ground Water
Restoration. EPA/540-R-93-080. September 1993.
EPA 1995. Superfund Administrative Reforms Overview. October 1995.
Grant ( James L. Grant & Associates) 1993. Draft Characterization & Treatability Study, Report
of Results, J.H. Baxter Superfund Site, Weed, California. Prepared for Weed Remediation
Group. May 27, 1993.
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Grant (Grant Environmental) 1994, Draft Preliminary Soil Remediation Design Plan. Prepared
for Weed Remediation Group. August 17, 1994.
Grant (Grant Environmental) 1995. Final Groundwater Remedial Design Investigation Report.
Prepared for Weed Remediation Group. February 21, 1995.
ICF/Clement 1990. Endangerment Assessment Baxter /International Paper/Roseburg Site, Weed
California, (Draft), Prepared for CH2M Hill. April 30, 1990.
NRC 1994. Alternatives for Groundwater Cleanup. National Resource Council 1994.
Rumer, R. R. and Ryan M. E. 1995. Barrier Containment Technologies for Environmental
Remediation Applications.
SAIC (Science Applications International Corporation) 1990. Draft Feasibility Study,
Baxter/IP/Roseburg Site, Weed, California. Prepared for U.S. Environmental Protection Agency,
Region IX. April 27, 1990.
TRC (TRC Environmental Solutions) 1996a. Addendum to Prefinal (90%) Remedial Design
Report, Surface Soils, Area B and Ditch Sediments. Prepared for Weed Remediation Group.
TRC Environmental Solutions, Inc. April 1996.
TRC (TRC Environmental Solutions) 1996b. Draft Final (100%) Remedial Design Report
Ground Water/Slurry Wall Remediation System. Prepared for Weed Remediation Group. TRC
Environmental Solutions, Inc. May 1996.
TRC (TRC Environmental Solutions) 1998. E-mail Communication from T. Patterson to
R. Andrachek of Fluor/GTI. February 1998.
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III. RESPONSE SUMMARY
1.0 INTRODUCTION
The United States Environmental Protection Agency (EPA) held a public comment period from
September 29 through November 29, 1997 on EPA's Proposed Plan for revisions to the soils and
groundwater cleanup remedy at the J.H. Baxter Superfund Site (Baxter) in Weed, California.
The purpose of the comment period was to provide interested parties with an opportunity to
comment on the Proposed Plan and related documents prepared since the 1990 Record of
Decision (ROD) for the Baxter site. The Proposed Plan was issued on September 9, 1997, and,
along with other documents comprising the Administrative Record was made available at the
College of the Siskiyous Library in Weed, California, and the U.S. EPA Superfund Records
Center in San Francisco, California.
EPA held a public meeting on October 9, 1997, at the College of the Siskiyous in Weed,
California. At this meeting, EPA representatives described the alternatives evaluated for
groundwater and soils in the target area containing dense, non-aqueous phase liquids (DNAPLs),
presented EPA's preferred alternative and answered questions about the evaluation of the Baxter
site and the remedial alternatives under consideration.
Section 113(k)(2)(B)(iv) of the Comprehensive Response, Compensation and Liability Act
(CERCLA) requires that EPA respond to significant comments on the Proposed Plan.
2.0 SUMMARY OF COMMENTS AND AGENCY RESPONSES
During the public comment period, EPA received verbal comments from individuals at the public
meeting and written comments from individuals, from the North Coast Regional Water Quality
Control Board (NCRWQCB), and from the responsible parties - the Weed Remediation Group
(WRG). The comments and EPA's responses to the comments are presented below.
A. COMMENTS FROM COMMUNITY MEMBERS
Commentor: Georgia Baxter
Date: October 9, 1997, Public Meeting Transcript
1. Comment:
I'm Georgia Baxter, BAXTER. I'd like to say J. H. Baxter and Company, of course, is in full
support of this remedy, that we feel it is protective of human health and the environment, it's cost
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effective, and it's implementable most of all. We're looking forward to working closely with the
agencies in the upcoming construction next year and we want to work closely to ensure that this
is completed in a cost effective manner and that J. H. Baxter will be able to maintain its
operations throughout the implementation so that we can continue to support the community as
we have in the past. Thank you.
1. Response:
The EPA agrees with Mrs. Baxter that the remedy chosen is an implementable, and functional
remedy. Our purpose is not to impede operations at JH Baxter during the remedial action, and
with your cooperation we hope to carry out the construction in the most expeditious and cost-
effective manner. If we are able to work together in a cooperative fashion, there is no doubt we
will achieve that goal.
Commentor: Marilyn Blankenship
Date: October 9, 1997, Public Meeting Transcript
2. Comment:
I'm Marilyn Blankenship, Blankenship. I would like to know if there is any way to find out now
whether our soil is safe for gardens. I understood that a few years ago they sent out a thing
saying you shouldn't eat vegetables from your garden, which I never got one like that. I grow a
garden and feed it to my family and would just like to know that if there's a way to have your soil
tested that the EPA would do that.
2. Response:
Inquiries were made with all the official health agencies that may have prepared a flyer such as
the one mentioned above, but none could be identified. The data we have gathered on Site
contamination and the surrounding areas give us no reason to believe that the soil in the
communities' yards is contaminated.
EPA did soil testing in the surrounding neighborhoods. No elevated levels of no contaminants
of concern were detected. However, if there was evidence to suggest that additional testing was
required, the EPA or California Department of Toxic Substances could perform additional
screenings. Another option would be to send in some of the vegetables you have grown for
testing.
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Commentor: Marilyn Blankenship, Weed, California
Date: written comment, no date
3. Comment:
I appreciated the informational community meeting at COS on October 9, 1997. I have also
written a letter to the editor of our local paper thanking the EPA, Gale Jensen (WRG), Baxter's
and Roseburg for their part in the cleanup.
I do have a concern about the overpowering creosote smell that occurs during the process of
cleaning the section of din that they have been adding bacteria to (although it smells like creosote
to me, some describe it as a "mothball odor.") This last summer it made our eyes burn and
irritated our sinuses. We even had two friends cut their visit short because it was bothering them.
Is there some way this problem could be addressed? Is the building of the slurry wall also going
to make this problem worse while they are excavating?
I spoke to Ed Cargile, California EPA, who explained the reduced risk of cancer after the
cleanup. I would like to know the health risk to people at the present time.
I have also requested that the spill in my yard be tested and would like to be notified of the
results.
Thank you once again for all your efforts.
3. Response:
The EPA is committed to involving the community in the entire Superfund Process. We thank
you for your participation and will continue to answer your questions, keep you informed, and
service your heeds.
The naphthalene odor emanating from the JH Baxter Superfund Site (Site), generated during the
landfarming operations in October of 1997, was a result of the tilling of soil contaminated with
organic compounds. Many neighbors to the Site were concerned that the naphthalene may be
harmful and complained of the offensive and strong smell. A study was done to test whether the
fumes were harmful to the workers. It was determined that individuals working next to the
substance were not at risk. Therefore, there is no present risk to individuals that live near the
Site.
It is still clear that although the naphthalene is not harmful, it is very unpleasant. The
landfarming is currently covered, but in the spring it will be uncovered. If more tilling is
necessary, measures will be taken to prevent the recurrence of the strong odors. If need be, the
landfarming may be covered after tilling, or some other alternative remedy.
The building of the slurry wall should not make this problem worse because the excavation will
occur around the DNAPL's (the substance responsible for the odor). DNAPL's should not be
encountered during the slurry wall construction.
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Testing of soil near the Site has been conducted. No elevated concentrations of contaminants of
concern have been found in the soil adjacent to the Site. The soil testing Mrs. Blankenship refers
to in her letter was done by the State EPA Department of Toxic Substances Control, and they
will notify her of the result.
Commentor: H. Hansard, Weed, California
Date: written comment, no date
4. Comment:
In addition to my concern about the air quality at the Roseburg Baxter site (a problem that has
been going on for at least 5 years since I've been there) (I've lived next door to the Baxter site for
5+ years) I'm most concerned about the noise level. Even though the new plant built by
Roseburg is "state of the art" the increased noise level is so bad that I cannot sleep in my house at
night. Only one room can be used for sleeping at night because the noise level from the
Roseburg Baxter site is very loud. (Noise from train/logging, etc.)
4. Response:
The air quality issue has been addressed above, but to reiterate, their is no risk to health from the
odor of the fumes the community has experienced.
Noise generated by the operations at JH Baxter and Roseburg Forest Products is not part of the
scope of the remedy at this Site. Noise abatement is a county issue. You may wish to contact the
Siskiyou County Health Department at (530) 841-4040.
B. COMMENTS FROM STATE AGENCIES
Commentor: Susan A. Warner, North Coast RWQCB
Date: October 28, 1997
5. Comment:
The public comment period on the proposal to modify the groundwater and soils remedy is
coming to a close. The Regional Water Board has made informal comments, to the US
Environmental Protection Agency (US EPA) on the proposals to modify the remedy, and those
informal comments are still valid.
As you know, the Regional Water Board concurs with EPA's preferred alternative, which
includes the concept of a containment system for the dense, non-aqueous phase liquids and
associated contaminated groundwater. However, such a containment system is not currently
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consistent with Regional Water Board requirements, including the basin plan, which requires that
water quality objectives be met throughout the contaminant plume area. However, non-
attainment of water quality objectives can be recognized, and this remedy found to be consistent
with the Basin Plan if the Regional Water Board adopts a Containment Zone pursuant to State
Water Resources Control Board Resolution 92-47, as modified in 1996. Section ffl.H.7 of
Resolution 92-49 allows for containment zones to be established where the US EPA has
approved a Technical Impracticability Waiver, provided that:
a. the substantive provisions of Sections III.H.2.b., e., f., and g. are met;
b. interested parties described in DOLH.S.a. are included in the public participation
process; and
c. site information is forwarded from the approving agency to the Regional Water
Board so that sites for which Technical Impracticability Waivers have been
approved can be included in the master listings described in Section IH.H.10.
The Resolution 92-49 process involves consideration of this containment zone in a noticed public
meeting before the Regional Water Board. In our letter of April 17, 1997, we indicated to the US
EPA and to parties who received a copy of the letter that most of the substantive portions of
Resolution 92-49 will be met through US EPA's Technical Impracticability Waiver (TI Waiver)
process.
The provisions required by Resolution 92-49 that are not covered in the TI Waiver process
include off-site mitigation requirements, and specific contingency plan language in the event of a
containment zone failure. Measures to fulfill Resolution 92-49 off-site mitigation requirements
can include enhancement of water quality through reclamation activities at the site that would
reduce water diversions from Beaughton Creek. Additional specific measures to address
Resolution 92-49 requirements can be proposed by the responsible parties as pan of the Regional
Water Board public process for consideration of a contamination zone.
The Regional Water Board staff also concurs that additional proposed modifications to the soils
remedy may be needed. The Regional Water Board staff believes that disposal options for
treated soils outside of the containment (TI) zone need to be consistent with the existing record
of decision and Scope of Work document where feasible. Remediated soils should not be
disposed as surface soils without addressing the probable residual contamination present in these
soils and without further restrictions to ensure there is no threat to water quality. If soils outside
of the TI Waiver zone, such as Area B soils, are proposed for disposal or to remain in place in
areas which are not within the containment zone area, then the disposal area and controls would
need to be found to be in conformance with the provisions of Chapter 15, as required previously.
While there may be some flexibility under the engineered alternative section of Chapter 15
(§2510(b)), adequate design requirements for the protection of water quality would need to be
assured. This does not prelude use of alternative remediation, but would require that the PRPs
demonstrate with adequate technical information that such remediation of soil material at a
particular location would not be a short-term or long-term threat to water quality. If an adequate
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technical showing is made of the protectiveness of a proposal, the Regional Water Board could
concur with a site-specific and situation-specific determination that some alternative remediation
actions were appropriate.
Thank you for the opportunity of providing comments on the modifications to the groundwater
and soil remedy at the Weed site. Bill Erdei and I look forward to a continued close working
relationship with US EPA on cleanup of this site.
5. Response:
As explained in the Focused Feasibility Study (FFS) for the J.H. Baxter Site, EPA has concluded
that Section ffl.H of Resolution 92-49, pertaining to the designation of containment zones, is not
an ARAR for the construction of the slurry wall containment system. (See FFS, pages 6-12 and
6-13.) Section ffl.H is a waiver provision which is equivalent to the federal Technical
Impracticability (TI) waiver, as implemented under the CERCLA "Guidance for Evaluating the
Technical Impracticability of Ground Water Restoration," OSWER Directive 9234.2-25.
EPA has addressed your concerns about the 92-49 off-site mitigation requirements and
contingency plan requirements in the ROD Amendment. Specifically, the ROD Amendment
emphasizes reuse on the Roseburg log decks as the preferred disposal option for the treated
water. This will promote water reclamation at the Site and reduce water diversions from
Beaughton Creek. The ROD Amendment also incorporates contingency plan provisions in the
event of a containment zone failure.
EPA shares your concern about the disposal of treated soil as surface soils, and has decided to
exclude this soil disposal option in the ROD. The ROD requires that excavated and/or treated
soils be disposed of on-site in RCRA equivalent disposal cells. The only exception is Area B
soils, which may be left in place if EPA finds that bioventing will achieve standards that are
protective of ground water.
Commentor: Bill Erdei, North Coast RWQCB
Date: March 17, 1998
6. Comment:
". . . The state accepts the use of the "RCRA Groundwater Monitoring: Draft Technical
Guidance" in lieu of Chapter 15 monitoring requirements to monitor for potential releases from
the slurry wall containment system. The State disagrees with the characterization of some of the
Chapter 15 requirements in this ROD Amendment as only relevant and appropriate, but it is
satisfied that the remedial action will comply with all of the requirements".
7. Comment:
"The state disagrees with US EPA's conclusion that SRWCB Resolution No. 92-48, Paragraph
HI. H, is not a ARAR for the slurry wall containment system because the State believes that it
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imposes substantive conditions that must be meet prior to waving groundwater ARARs.
However, the State has determined that remedial action will substantively comply with
Resolution No. 92-49, and is therefore satisfied with this ROD amendment."
* * *
C. COMMENTS BY THE RESPONSIBLE PARTIES
Commentor: Richard Andrachek, Fluor Daniel GTI
Date: November 20, 1997
This letter provides the Weed Remediation Group's (WRG) comments on the Proposed Plan for
the JH Baxter Superfund Site in Weed, CA, which was issued by EPA in late September, 1997.
The WRG has three comments, which are provided below an the Proposed Plan. 7.
Comment:
Comment 1 - The WRG is in support of the modifications to the groundwater and soils remedy
identified in the Proposed Plan. The WRG believes that the modifications discussed in the
Proposed Plan are protective of human health and the environment, can be effectively
implemented over a two year period with manageable disruption to the business operations of JH
Baxter and Roseburg Forest Products and are cost-effective.
Comment 2 - Sufficient flexibility needs to be incorporated into the Proposed Plan for
management of contaminated soils that may be excavated after the remedy is implemented. The
Proposed Plan will allow existing impacted subsurface soils to remain in place in areas of the site
that are within the slurry wall (TI Zone). The WRG believes that the Proposed Plan should
include the option of reusing any contaminated subsurface soils that may be excavated due to
future construction as subsurface backfill at other locations within the slurry wall. The WRG
believes that these management approaches are consistent with approaches provided by EPA's
rules on RCRA Corrective Management Units (CAMU) (40 CFR 264.552) and "Areas of
Contamination (AOC)" (OSWER Directive 93473-05FS, July 1989). Designation of a CAMU
or AOC would facilitate a reliable, protective, long-term solution for the management of
contaminated soils that may be excavated post-remedy. Additionally, contingency language
should be provided to allow for reopening or extending the RCRA-equivalent disposal cell for
disposal of these soils if excavated post-remedy.
Comment 3 - Previous design submittals for the surface soil have included placement and
maintenance of a gravel wearing surface over the southern portions of the J.H. Baxter Property.
The Proposed Plan fails to mention the inclusion of the gravel wearing surface and states that any
wearing surfaces placed at the site would be constructed of asphalt-concrete. The WRG requests
that the proposed gravel wearing surface be included in the remedy modifications. The gravel
wearing surface has already been incorporated as redundant protection of the surface soils in this
J. H. Baxter III - 7 March 26. 1998
ROD Amendment Printed on Recycled Paper
ARrS.Propccu/Baxict/Baj.ruda/DECSUM KI.DOC
-------
area, since the area will be remediated to below the surface soils excavation standard established
in the Record of Decision (ROD). After excavation, the average arsenic concentration will be
equal to or less than the ROD-established cleanup standard of 8 mg/kg. Other chemicals for
which cleanup standards have been established in the ROD are already below their respective
criteria in this area of the site. Therefore, placement of an asphalt concrete wearing surface in
this area is overly protective and very costly, while the gravel wearing surface provides adequate
protection at a reasonable cost.
Thank you for considering these comments. Please call me (510/370-3990) if you would like to
discuss these comments.
8. Response:
As stated above in response to Georgia Baxter's statement, we are pleased that we have been able
to develop modifications to the groundwater and soils remedy that are protective of human health
and the environment, and are acceptable to EPA and the WRG.
The EPA would like to give flexibility to operations at JH Baxter and Roseburg Forest Products,
but has a primary responsibility to human health and the environment. Leaving contamination in
place for perpetuity is not a preferred remedy, and must be monitored very carefully.
Consequently, the remedy will include institutional controls to ensure that the remedy remains
protective. EPA will work with the WRG to develop a Soils Management Plan that would set
out a course of action to be taken in the event that contaminated soils are excavated during future
construction. This plan may include use of the RCRA-equivalent cell for possible disposal of
contaminated soils excavated subsequent to the implementation of the remedy.
Your proposal of a gravel wearing surface rather than an asphalt wearing surface is acceptable.
As you stated in your comment letter of November 20, 1997, the soils underlying the gravel
wearing surface will be remediated to below the surface soils excavation standard established in
the 1990 Record of Decision.
J. H. Baxter HI - 8 March 26, 1998
ROD Amendment Printed on Recycled Paper
ARCS.Proiccu/Bwiri/Bu.ruIa/DECSUM II) DOC
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TABLES
-------
Table 1-1
Pre-1990 ROD Contaminant
Concentration Ranges
Subsurface Soils
Ground Water
Arsenic
Chromium
Copper
Zinc
Penlachlorophenol (PCP)
Carcinogenic PAHs1 (cPAH)
Non-Carcinogenic PAHs2 (ncPAH)
Benzene
Dioxins
Average Site
Levels
(ppm)
21
12
II
40
160
18
30
0.0035
Maximum Site
Levels
(ppm)
12,100
1,350
604
1,120
1,300
420
6,100
5.7
Average Site
Levels
(ppb)
37
13
170
2
360
635
8
12
Maximum Site
Levels
(ppb)
1,740
122
37,100
23,000
210
6,000
251,800
170
13
Source: ROD Table 4-1
Carcinogenic PAHs: Benzo(a) anthracene, Chrysene, Benzo(b)fluoranthene, Benzo(a)pyrene,
Benzo(k)fluoranthene, Indeno (1,2,3-cd)pyrene.
Non carcinogenic PAHs: Naphthalene, 2-melhylnapihalenc, Acenaphthylene, Accnaphthene, Dibcnzofuran,
Fluorene, Phenamhrene, Anthracene, Fluoranihene, Pyrene. Benzo(ghi)perylene.
J. H. Baxter
ROD Amendment
ARCS_Projects\Baxler\Tl_01MAR.DOC
March 26, 1998
Printed on Recycled Paper
-------
Table 4-1
Excavation and Treatment Standards in the 1990 ROD
CONSTITUENTS OF
CONCERN
Arsenic
Chromium
Copper
Zinc
Penlachlorophenol (PCP)
Tetrachlorophenol
Carcinogenic PAHs (cPAH)3
Non-carcinogenic PAHs
(ncPAH)4 •
Dioxins
Furans
ROD Standards
SURFACE
SOIL
EXCAVATION
STANDARDS'
(mg/kg)
8
500
2,500
5,000
17
2,800
0.51
43,000
0.001
0.001
SUBSURFACE SOIL
EXCAVATION
STANDARDS2
(mg/1)
5 (TCLP)
5 (STLC)
25 (STLC)
250 (STLC)
1.7 (STLC)
Not present in
subsurface soil
0.005 (TCLP)
1.0 (TCLP)
0.001 (TCLP)
Not Specified in
1990 ROD
SEDIMENT
EXCAVATION
STANDARDS2
(mg/kg)
8
18
Not present in
sediment
26
1.0
1.0
0.5
0.5
Not present in
sediment
Not present in
sediment
SOILS
TREATMENT
STANDARDS2
(mg/1)
5 (TCLP)
5 (STLC)
25 (STLC)
250 (STLC)
1.7 (STLC)
1.0 (TCLP)
0.005 (TCLP)
1.0 (TCLP)
0.001 (TCLP)
Not Specified in
1990 ROD
J.H. Baxter
ROD Amendment
ARCS_Projects\BAXTER\02_RODA\T4_01MAR.DOC
1 Of 3
March 26, 1998
Printed on Recycled Paper
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Table 4-1 (Continued)
Excavation and Treatment Standards in the 1990 ROD
CONSTITUENTS OF
CONCERN
Arsenic
Chromium
Copper
Zinc
Benzene
Pentachlorophenol
Carcinogenic PAHs (cPAH)
Non-Carcinogenic PAHs
(ncPAH)
Dioxins
ROD Standards
AQUIFER CLEANUP AND GROUNDWATER
TREATMENT STANDARDS2 (mg/1)
0.005
0.008
0.011
0.090
0.001
0.0022
0.005
0.005
2.5 x 10"8
Abbreviations:
PAH - polynuclear aromatic hydrocarbon
ppm - parts per million
ROD - Record of Decision
STLC - Soluble Threshold Limit Concentration
TCLP - Toxicity Characteristic Leaching Procedure
TTLC - Total Threshold Limit Concentration
J.H. Baxter
ROD Amendment
ARCS_ProjecU\BAXTER\02_RODA\T4_OIMAR.DOC
2of3
March 26. 1998
f Tinted on Recycled Paper
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Table 4-1 (Continued)
Excavation and Treatment Standards in the 1990 ROD
Notes:
I) From 1990 ROD, Table 4-3.
2) From 1990 ROD, Table 4-1, and 1990 ROD Section 11.
3) cPAHs: Benzo(a)anthracene, Chrysene, Benzo(b)nuoranthene, Benzo(a)pyrene, Benzo(k)fluoranthene,
Indeno( 1,2,3-cd)pyrene
4) ncPAHs: Naphthalene, 2-methylnaphthalene, Acenaphthylene, Acenapththene, Dibenzofuran, Fluorene,
Phenanthrene, Anthracene, Fluoranthene, Pyrene, Benzo(ghi)perylene
J.H. Baxter
ROD Amendment 3 of 3 March 26, 1998
ARCS_ProjecU\BAXTER\02_RODA\T4_OIMAR.DOC Printed on Recycled Paper
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Table 4-2
Excavation and Treatment Standards in the ROD as Modified by the ROD Amendment
CONSTITUENTS OF
CONCERN (COC)
Arsenic
Chromium
Copper
Zinc
Pentachlorophenol (PCP)
TetrachJorophenol
Carcinogenic PAHs
(cPAH)f
Non-carcinogenic PAHs
(ncPAH)4
Dioxins
Furans
Amended ROD Standards
SURFACE SOIL
EXCAVATION
STANDARDS
(mg/kg)
8
500
2,500
5,000
17
2,800
0.51
43,000
0.001
0.001
SUBSURFACE
SOIL
EXCAVATION
STANDARDS1
5 (TCLP) (mg/1)
5 (STLC) (mg/1)
25 (STLC) (mg/1)
250 (STLC)
(mg/1)
7.4 (mg/kg)
Not present in
subsurface soil
3.4 (mg/kg)
3.4 (mg/kg)
0.001 (mg/kg)
0.001 (mg/kg)
SEDIMENT CLEANUP
STANDARDS
(NATURAL
ATTENUATION)
(mg/kg)
8
18
Not present in sediment
26
1.0
1.0
0.5
0.5
Not present in sediment
Not present in sediment
TREATMENT
STANDARDS FOR SOILS
PLACED IN RCRA-
EQUIVALENTCELL2
(mg/1)
5 (TCLP)
5 (STLC)
25 (STLC)
250 (STLC)
1.7 (STLC)
1.0 (TCLP)
0.005 (TCLP)
1.0 (TCLP)
0.001 (TCLP)
0.001 (TCLP)
J.H. Baxter
ROD Amendment
AR<:S_Projecii\BAXTER\02_RODA\T4_02MAR.DOC
1 Of 3
March 26, 1998
Printed on Recycled Paper
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Table 4-2 (Continued)
Excavation and Treatment Standards in the ROD as Modified by the ROD Amendment
CONSTITUENTS OF
CONCERN (COC)
Arsenic
Chromium
Copper
Zinc
Benzene
Pentachlorophenol
Tetrachlorophenol
Carcinogenic PAHs
(cPAH)
Non-Carcinogenic PAHs
(ncPAH)
Dioxins
Furans
Amended ROD Standards
TREATMENT
STANDARDS FOR
AREA B5 (mg/kg)
Not a COC for
Area B soil
Not a COC for
Area B soil
Not a COC for
Area B soil
Not a COC for
Area B soil
Not present in
Area B soil
7.4
Not present in
Area B soil
3.4
3.4
0.001
0.001
AQUIFER CLEANUP
AND GROUNDWATER
TREATMENT
STANDARDS (mg/1)
0.005
0.008
0.011
0.090
0.001
0.001
1.1
0.005
0.005
2.5 x 10'8
Not present in groundwater
GROUNDWATER
TREATMENT STANDARDS
FOR DISCHARGES TO
BEAUGHTON CREEK (mg/1)
0.005
0.005
0.005
0.010
0.001
0.0003
0.0004
0.001
0.001
2.5 x 10'8
Not present in groundwater
J.H. Baxter
ROD Amendment
ARCS_ProjecU\BAXTER\02_RODA\T4_02MAR.DOC
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March 26, 1998
Printed on Recycled Paper
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Table 4-2 (Continued)
Excavation and Treatment Standards in the ROD as Modified by the ROD Amendment
Abbreviations:
cPAH - carcinogenic PAH
COC - Constituents of Concern
ncPAH - noncarcinogenic PAH
PAH - polynuclear aromatic
hydrocarbon
ppm - parts per million
ROD - Record of Decision
STLC - Soluble Threshold Limit
Concentration
TCLP - Toxicity Characteristic
Leaching Procedure
Notes:
1) There will be no excavation of subsurface soils in the TI zone.
2) Standard tests will be modified by the use of deionized water as the leaching solution rather than a citric acid
buffer.
3) cPAHs: Benzo(a)anthracene, Chrysene, Benzo(b)fluoranthene, Benzo(a)pyrene, Benzo(k)fluoranthene,
Indeno(l ,2,3-cd)pyrene
4) ncPAHs: Naphthalene, 2-methylnaphthalene, Acenaphthylene, Acenapththene, Dibenzofuran, Fluorene,
Phenanthrene, Anthracene, Fluoranthene, Pyrene, Benzo(ghi)perylene
5) If in situ bioventing of Area B soils is not successful, soils will be excavated and treated to the soil treatment
standards, and disposed of in a RCRA-equivalent cell. If in situ bioventing is capable of achieving the treatment
standards, the Area B soils will be left in place after treatment has been completed. Area B soils which do not
meet the surface soil excavation standard will be covered with 2 feet of clean soil and left in place after treatment
has been completed.
J.H. Baxter
ROD Amendment
ARCS_Projecls\BAXTER\02_RODA\T4_02MAR.DOC
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March 26. 1998
Printed on Recycled Paper
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TABLE*-!
SELECTED REMEDIES FOR ALL MEDIA COMPONENTS AT THE J. H. BAXTER SUPERFUND SITE
COMPONENT
Component 1 • Soils Conumiiuied with lnor|anica Only
Conponca 1 - SoiU Cootaminaud with Organic* Only
Component ) • Soib Ccnlaminiud »Uk Orfinict and IflOf ganki
Ihc
il
the
Ihc
REMEDY
lhc
il
Ine
mil
(minf I
ten), hgt
J k-jrtue
d WMCI
1990 ROD
Remedy
Eicavaie.
Hi inorianict aa neceaaary.
Place in lined disposal cell if ctceeda kuardoui waau criteria.
BacUin and cover with 2 feet of toil If k don oa
eiceed huardoiu waste criteria.
EaCtvaK,
Biotnal * MCOaary •> cleanup tundana,
r^feiMtfhpoulct*.
tUcavaM.
Biouul at noceuary.
Ha loor|ank> » necruary.
Place in a kned tttpotal eel.
1997 ROD
Amcndmcnl
Remedy
Eacavate.
Treat by
fUauon.
Dupote of in
RCRA
equivalent
ditpoul cell.
Eiuvaie,
Diipmeof i*
RCRA
equivalent
dupoul cell
Leave in plat*.
Repack
Cover with
aiptuliic
concrete
wearin| surface.
Implement
tnunuuonal
cant roll.
MawcivaiioB
or treatment
caceptfor
radincof
Roietwt
eicavation;
cover «atn 2
feel of clean
soil
Implement
uiukuiional
control!.
Eicavm
BkXreJtnaM
wilkoponiu
perfon
treat mem
to fin
(hndfamtini )•
Difpoaeofi*
RCRA
equivalent
Eicaven.
DtapoMWU
RCRA cow valcnt
dUpoulccU.
Notuivattaaot
trutmcnl eacepl
Rxtteburj
euavation;
cover onb 2 f*tt
of clean toil.
Implement
uiuiiuuonal
conuola.
Btoueatment
In-situ utlnf
blovemin(.
tfte-iinj
biovcntinf i*
unwcccaaful.
remedy urneu
EicavMe.
Bnueaunent
Rtaljon of
RCRA dibiva
diipuMlccU.
Eicavate.
DupOMOfi*
RCRA equivilew
dupoulua
No eacavaiion or
Ireaunenl cuerx
for fndinf of
Roxburi
eacavation: cover
»«hj feel of clean
toil.
Implement
institutional
contrail.
-------
TABLE*-!
(Conllnued)
SELECTED REMEDIES FOR ALL MEDIA COMPONENTS AT THE J. IL BAXTER SUPERFUND SITE
REMEDY
1990 ROD Remedy
1997 ROD Amendment
Remedy
Component 4 • Croundwatef
J
\'
if
*
3
ll
ii
tS
£itr*a coftt.vniju.ud ipDuntfvaitf, m* ID ROD sundirds.
duchtftt tiutcd frouAdwMcr. aod ctuoup of Aquibr 10 KOD
Enhance the 1990 ROD
pouiidwaa nrnedjr by
cotul/uciuif • Ui«Ty wafl
aretnd the DNAFL Zone.
Rcfrade and cover (he
Roubwi eicavMMMX
No treatment of jrevnJwMc*'
«ul.tA (tuny w*II coflUUHnenl
»>u«m Cottecuaa and
beaiinenl ol li«|u»di f(om
DNAPL tcept m the Rowbuff
ClUVtfKML
cunifolt to rcumi ACCCSI and
u« of co«jinifuJ(d
CrnunJwaict. to prevera
ctpuuire to tuic LiO in the
DNAPL cone, and to pmiccl
the tnfcjniy of the icnvdjr.
Enhance rhi IMO ROD
frtMndwucT remedy by
comvuaini • tturry waN
around the DNAPL Zone.
Euna conuminaitd
gnundwaicr. treat to ROD
oandar da. and diicharee intaied
imtndwaier.
Cleanup Aqufetla ROD
T*"Mlarilt
COMPONENT
Componem J . Surface W«ier
J
J
Jt
Control and out oontaminalBj runoff
•» »"•'••• ^UHIIWIl ^ !••
chtmkiti IBID luufbio* Crack.
Diichtrp of Betuttnei Creek
added ID pniible oupoul option*
for treated fmndweler. prdnred
option Bill rctae o> Raeeturj'i lo|
decb.
Component 6- Sediment
iaDtichet
B
j
J
*
Bicentt.
Treat and dlqne H (or aoll
eoByoninu 1. 1 end 1.
DMi lediinrnti vIB be lOrwed K)
continue lo dctnaV tuunlly.
Strum icdiniena "in cenanue la
be monitored end cautionary ii|o>
•in be potted la
-------
Table 8-1
Comparison of Remedial Alternatives
Criteria and Description
Ovci-iill I'
Protection of the human health and
(he environment, in the short and
long term, from unacceptable risks at
the site, by eliminating reducing or
controlling exposures to target
cleanup levels.
CompliaiKC' \»ilh AKAKs
Compliance with chemical-specific,
locution-specific, and action-specific
ARARs.
Alternative 1
No Further Action
(Slurry Wall Containment,
Hydraulic Control,
Monitoring)
Alternative 2
Excavation to Ground Water Table,
On-site Biotreatment, Stabilization,
On-site Disposal
Alternative 3
Additional Containment and
Institutional Controls
Source Control is achieved by
containment of the DNAPL zone
within the Target Area.
Risk of further migration of
contaminants within the Target Area is
minimized. There is no reduction in
potential risk to human health from
ingeslion of the ground water or
through direct contact with subsurface
soils.
Target levels for ground water and
subsurface soil concentrations are not
achieved.
Requires a waiver of the groundwaier
cleanup standards set forth in the ROD
based on the technical impracticability
from an engineering perspective, us
part of a ROD amendment.
DNAPL zone is contained within the Target Area.
A significant portion of the contaminated
subsurface soils removed and treated.
Risk of further migration of contaminants within
the Target Area is minimized. Exposure potential
to contaminants in subsurface soils is also
minimized. No reduction in potential risk through
ingestion of ground water is achieved.
Target levels for ground water in the upper
aquifer are not achieved, however, treated soil is
expected to achieve target soil leachate standards.
Source control is achieved by containment
of the DNAPL zone within the Target Area.
Roseburg Excavation is regradcd and
covered with a protective soil layer,
reducing potential for surface water
contamination and (caching into the
subsurface.
Risk of further migration of contaminants in
the Target Area is minimized. Exposure
potential to contaminants in subsurface
soils is reduced. Potential risk through
ingestion of ground water is reduced.
Target levels for ground water and
subsurface soil concentrations are not
achieved.
Requires a waiver of the groundwaier cleanup
standards set forth in the ROD based on the
technical impracticability from an engineering
perspective, as part of a ROD amendment.
Requires a waiver of the groundwaier
cleanup standards set forth in the ROD
based on the technical impracticability from
an engineering perspective, as pan of a
ROD amendment..
J.H. Baxter
ROD^rendment
ARO^Rects/Baxter/l02_roda/"nL01MAR.DOC
f6
March 26,v
Printed
-------
Table 8-lT^ntinued)
Comparison of Remedial Alternatives
Criteria and Description
Alternative 1
No Further Action
(Slurry Wall Containment,
Hydraulic Control,
Monitoring)
Alternative 2
Excavation to Ground Water Table,
On-site Biotreatment, Stabilization,
On-site Disposal
Alternative 3
Additional Containment and
Institutional Controls
Magnitude of residual risk from
untreated waste.
Magnitude of residual risk to receptors
outside the Target Area from untreated
waste within the Target Area is
reduced, since slurry wall containment
prevents further migration of
contaminants from the Target Area.
Inside the Target Area, no risk
reduction is achieved. No institutional
controls are provided to eliminate or
minimize the potential pathway for
exposure to contaminants left in the
subsurface soils.
Alternative 2 permanently reduces the magnitude
of, but does not completely eliminate the residual
risk from untreated waste because some residual
waste will still remain within the Target Area.
However, no institutional controls are provided,
and therefore, the possibility of exposure to the
contaminated subsurface soils remaining in place
is not eliminated. The potential risk associated
with ingestion of contaminated groundwater is
also not eliminated.
Alternative 3 reduces the magnitude of the
residual risk due to contaminated
groundwater and untreated waste through
institutional controls and rcgrading and
placing a protective soil cover over the
Roseburg Excavation, but does not
eliminate the potential for future increased
risk if institutional controls are not
implemented and maintained.
Adequacy and reliability of long-
term management controls.
Reliability of slurry wall containment
depends on continued ground water
monitoring, effectiveness evaluation.
implementing contingency actions
when needed, and maintenance.
Reduction <>f I <>\ii ilv. Mobility. ;m
-------
Table 8-1 (Continued)
Comparison of Remedial Alternatives
Criteria and Description
Kc'diK lion of
Alternative 1
No Further Action
(Slurry Wall Containment,
Hydraulic Control,
Monitoring)
Alternative 2
Excavation to Ground Water Table,
On-site Biotreatment, Stabilization,
On-site Disposal
Alternative 3
Additional Containment and
Institutional Controls
Mobility. ;
'onliMiii'(l)
Degree of reduction in toxicily,
mobility, or volume.
Mobility of contaminants within the
Target Area is reduced by the slurry
wall containment system.
No reduction in toxicity or volume of
the subsurface soil contaminants is
achieved (no treatment).
The volume and toxicity of (he COCs
in groundwater within the Target Area
will be somewhat reduced over a long
period of time.
Mobility of contaminants within the Target Area
is reduced by the slurry wall containment.
Reduction in volume and toxicity of the organic
contaminants in the subsurface soils is achieved
through removal and biotreatment. Stabilization
immobilizes the inorganic contaminants, but does
not reduce volume or loxicity.
The volume and toxicity of the COCs in
groundwater within the Target Area will be
somewhat reduced over a long period of time.
Mobility of contaminants within the Target
Area is reduced by the slurry wall
containment.
Some additional reduction in mobility is
achieved through regrading and placement
of a protective soil cover over the Roseburg
Excavation. No reduction in volume or
toxicity of the subsurface soil contaminants
is achieved (no treatment).
The volume and toxicity of (he COCs in
ground water within the Target Area will be
somewhat reduced over a long period of
time.
Degree to which treatment is
irreversible.
Not applicable, no treatment
Irreversible for biotreatment. Stabilization of
inorganic contaminants may be partially
reversible, should stabilized soil breakdown
overtime.
Not applicable, no treatment
Type and quantity of residuals
remaining after treatment.
All impacted subsurface soils remain in
place.
Based on the minimum impacted soil volume
estimate, approximately 64,000 cy is left in place.
Based on the maximum impacted soil volume
estimate. 564,000 cy of impacted soils is left in
lace.
All impacted subsurface soils remain in
place.
Short-term risks to (he community
during implementation of an
alternative.
Slurry wall construction is not
anticipated to pose any risks to the
community.
Excavation, treatment, and disposal of large
quantities of soil could pose a health risk, and
odor nuisance for the community. Monitoring
and control of dust emissions and odor would be
implemented during execution of this alternative.
Transportation of large quantities of soil could be
a potential nuisance to the community, and a
potential traffic hazard.
If the Roseburg Excavation is covered,
transportation of imported soils would not
pose a health risk, but could be a nuisance
for the community, as well as a traffic risk
for vehicular accidents.
J.H. Baxter
ROD Amendment
ARQMkPJects/Baxter/02_roda/T8_01MAR.DOC
Page 3 of 6
March 26, 1998
Printed on Recycled i
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Table 8-lTTontinued)
Comparison of Remedial Alternatives
Criteria and Description
Alternative 1
No Further Action
(Slurry Wall Containment,
Hydraulic Control,
Monitoring)
Alternative 2
Excavation to Ground Water Table,
On-site Biotreatment, Stabilization,
On-site Disposal
Alternative 3
Additional Containment and
Institutional Controls
Potential impacts on workers during
remedial actions, and effectiveness,
and reliability of protective
measures.
There is a potential for exposure to
fugitive dust and to soils contaminated
with carcinogenic compounds during
slurry wall trench excavation activities.
Protection from potential risks is
achievable with standard practices.
There is increased potential for exposure to
fugitive dust and to soils contaminated with
carcinogenic compounds during excavation
activities due to the high quantities of soils to be
excavated. Dust and. odor is an issue during
landlarming. Dust is also an issue during
stabilization. Control of potential risks is
achievable with standard safety practices.
There is a potential for exposure to fugitive
dust and to soils contaminated with
carcinogenic compounds during slurry wall
trench excavation activities and early stages
of the Roscburg Excavation area rcgruding
and covering operations. Control of
potential risks is achievable with standard
safely practices.
Potential environmental
impacts/mitigation measure
effectiveness.
There is a potential for adverse
environmental impacts if free-phase
DNAPL is encountered during trench
excavation and/or if the OCA is
penetrated, and uncontrolled migration
of the DNAPL occurs.
There is a potential for adverse environmental
impacts if free-phase DNAPL is encountered
during trench excavation and/or if the OCA is
penetrated, and uncontrolled migration of
DNAPL occurs.
There is a potential for adverse
environmental impacts if free-phase
DNAPL is encountered during trench
excavation and/or if the OCA is penetrated.
and uncontrolled migration of DNAPL
occurs.
Time until protection is achieved.
Imnk'NK'iihibilitv
Technical feasibility.
Within I year
Soil-bentonite slurry wall is a
conventional technology readily
installed and maintained.
Within 3-5 years for the minimum impacted soils
volume estimate, and 5-1 years for the maximum
impacted soils volume estimate, after
implementation of the slurry wall containment
baseline remedy.
Soil-bentonite slurry wall is a conventional
technology readily installed and maintained.
Technology, equipment, and services for
excavation and treatment processes included
under this alternative are readily available and
relatively easily implemented. However, high
quantities of imported soil needed for backfilling
may not be readily available from a nearby source.
Also, extensive areas required for landfarming
may pose a problem, as well as the areas needed
for the RCRA disposal cells. Odor and dust can
be problem during implementation. Also,
remedial activities could significantly impact site
rations.
Within I to 2 years
Soil-bentonite slurry wall is a conventional
technology readily installed and
maintained. Services and equipment for
rcgrading and placing of a protective soil
cover over the Rbseburg Excavation would
be readily available. Approximately 33,400
cy of imported soil needed for backfilling
should be available from a nearby source.
J.H. Baxter
ROD Amendment
ARCS_Projecis/Baxter/02_roda/T8_01MAR.DOC
Page 4 of 6
March 26. 1998
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Table 8-1 (Continued)
Comparison of Remedial Alternatives
Criteria and Description
Alternative 1
No Further Action
(Slurry Wall Containment,
Hydraulic Control,
Monitoring)
Alternative 2
Excavation to Ground Water Table,
On-site Biotreatment, Stabilization,
On-site Disposal
Alternative 3
Additional Containment and
Institutional Controls
Availability of services and
materials.
Slurry walls are considered to be
reliable containment systems when
built properly.
Additional remedial actions can be
implemented within the Target Area.
Effectiveness of containment will be
monitored through groundwater and
DNAPL monitoring
Services and equipment for
construction of slurry walls are readily
available.
Slurry walls are considered to be reliable
containment systems when built properly.
Reliability of excavation in removing the COCs
would depend on the delineation of the extent of
contamination in the subsurface. Landfarming
has been shown to be reliable in reducing the
concentrations of ncPAHs. and stabilization in
reducing the leachability of the inorganic COCs.
Excavation of approximately 900,000 cy of soils,
and treatment by landfarming would interfere with
additional remedial actions during their
implementation. Additional remedial actions can
be implemented subsequently.
Effectiveness of the slurry wall containment will
be monitored through ground water monitoring.
Effectiveness of bioremedialion and stabilization
will be evaluated through sampling during
remediation.
Services and equipment are readily available for
construction work. Obtaining approximately
700,000 cy of clean imported soil from a nearby
source may not be possible. Vendors offering
landfarming and stabilization technologies are
available.
Slurry walls are considered to be reliable
containment systems when built properly.
Institutional controls have to be managed
for the long-term for reliability
Additional actions can be readily
implemented. Slurry wall, regrading and
covering the Roseburg excavation or the
institutional controls would not interfere
with other remedial alternatives.
Effectiveness of the slurry wall containment
will be monitored through ground water
monitoring.
Community relations, legal services, and
contractors are available. Obtaining
approximately 33.400 cy of clean imported
soil from a nearby source should be
possible. Effective institutional controls
have been implemented at other Supcrt'und
sites.
J.H. Baxter
ROMfcpend merit
AR^Htjects/Baxler/,02_roda/TS_01MAR.DOC
f6
March 26
Printed on Recycled
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Table 8-1 (Continued)
Comparison of Remedial Alternatives
Criteria and Description
Alternative 1
No Further Action
(Slurry Wall Containment,
Hydraulic Control,
Monitoring)
Alternative 2
Excavation to Ground Water Table,
On-site Biotreatment, Stabilization,
On-site Disposal
Capital Costs.
$25,000">- I58.000'2'
Alternative 3
Additional Containment and
Institutional Controls
$1.000
Annual O&M Costs.
$46«"«"-
m (J) i m n> O)
$8'
Total Project Cost (Capital plus JO-
SI.300
ear O&M. Present Worth)
Acceptable in concept and preferred
(I} Cost bused on Ihe minimum impacted soil volume estimate.
(2) Cost based on the maximum impacted soil volume estimate.
(3) Annual O&M costs above do not include the 5-year review cost of $30,000 (assumed) recurring every 5 years. However, it is included in Ihe present worth estimates.
Source: FFS Table 6-3
J.H. Baxter
ROD Amendment
A RCS.Projects / Baxter/02.roda/T8_01M A R. DOC
Page 6 of 6
March 26, 1998
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Table 8-2
Federal Applicable or Relevant and Appropriate Requirements
J. H. Baxter Superfund Site 1990 ROD
Standard, Requirement, Criteria or
Limitation
Safe Drinking Water Act
Underground Injection Control Regulations
Solid Waste Disposal Act
(Resource Conservation and Recovery Act)
Identification and listing of Hazardous
Waste
Citation
Release from Solid Waste Management
Units
Standards Applicable to Generators of
Ha/ardous Waste
40 U.S.C. §300
40 C.F.R.
Parts 144-147
42 U.S.C.
§§3251-3259,
6901-6987
40 C.F.R.
Part 264.1
Description
Comments
40 C.F.R.
Part 264
Subparl F
40 C.F.R.
Part 262
Provides for protection of
underground sources of drinking
water.
Defines those solid wastes which are
subject to regulation as hazardous
wastes under 40 C.F.R. Parts 261 -
265 and Parts 124, 270, 271, and
Subtitle C regulates treatment and
disposal of hazardous waste.
Establishes maximum contaminant
concentrations (h_at can be released
from hazardous waste units in Part
264, Subpart F.
Establishes standards for generators
of ha/ardous waste.
A permit is not required for on-site CERCLA
response actions, but substantive requirements
would apply for reinjection into groundwater of
treated water.
This law has been amended by the Resource
Conservation and Recovery Act (RCRA) and the
Hazardous and Soil Waste Amendments (HSWA).
Under CERCLA, SWDA requirements may be
relevant and appropriate under the circumstances of
the release at the site. RCRA Subtitle C regulates
any solid wastes containing arsenic or
pentachlorophenol which pose a threat to public
health or welfare or the environment. These are
termed "hazardous substances", and disposal
regulations require treatment to specific standards
for proper disposal.
The maximum contaminant concentrations that can
be released from hazardous waste units are identical
to the MCLs.
Transportation and disposal of filter cake and spent
carbon and any other hazardous wastes they may
need off-she disposal will comply with these
requirements.
J.H. Baxter
ROD Amendment
ARCS_Projcels\Baxler\T8_02MAR.DOC
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March 26, 1998
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Table 8-2 (Continued)
Federal Applicable or Relevant and Appropriate Requirements
J. H. Baxter Superfund Site 1990 ROD
Standard, Requirement, Criteria or
Limitation
Standards lor Owners and Operators of
Hazardous Waste Treatment, Storage, and
Disposal Facilities
Land Disposal
Citation
Description
Comments
Clean Air Act
Hazardous Materials Transportation Act
Hazardous Materials Transportation
Regulations
Fish and Wildlife Coordination Act
40C.F.R.
Pan 264
RCRA
Sections 3004 (d)
(3, (e)(3)
40 C.F.R. Part
268
42 U.S.C.
§§7401-642
49 U.S.C.
§§1801-1813
49 C.F.R.
Parts 107, 171-177
16 U.S.C.
§§661-666
Establishes minimum national
standards which define the
acceptable management of hazardous
waste for owners and operators of
facilities which treat, store, or
dispose of hazardous waste.
Effective 11/8/88 disposal of
contaminated soil or debris from
CERCLA Response action or
disposal prohibitions and/or
treatment standards.
Regulates air quality and paniculate
emissions during excavation.
Regulates transportation of
hazardous materials.
Requires consultation when Federal
Department or agency proposes or
authorizes any modification of any
stream or other water body and
adequate provisions for protection of
fish and wildlife resources.
The substantive portions of these regulations will
be incorporated into the remedies identified in (his
ROD.
Established a timetable for restriction of burial of
wastes and other hazardous materials. Applicable
for alternative involving off- or on-site disposal of
contaminated soils.
The substantive requirements will be met for Air
Pollution Control District rules for excavation
alternatives.
Regulations required for transportation of
hazardous materials to the site and wastes from the
site.
If an alternative developed would involve any
modifications of nearby stream.
J.H. Baxter
ROD Amendment
ARCS_Projecls\Baxtei\T8_02MAR.DOC
2 of 3
March 26. 1998
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Table 8-2 (Continued)
Federal Applicable or Relevant and Appropriate Requirements
J. H. Baxter Superfund Site 1990 ROD
Standard, Requirement, Criteria or
Limitation Citation Description Comments
Executive Order on Protection of Wetlands Exec. Order Requires Federal agencies to avoid If an alternative developed would involve any
... .. _„„ to the extent possible, the adverse modification or loss of wetlands.
No. 11,990 . , . . .
impacts associated with the
destruction or loss of wetlands and to
avoid support of new construction in
wetlands if u practical alternative
§6.302(a) and exists.
Appendix A
Source: FFSTable2-l
J.H. Baxter
ROD Amendment 3 of 3 March 26, 1998
ARCS_Prujecis\BaxiertT8_02MAR.DOC Printed on Recycled_P«per
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Table 8-.1
California Applicable or Relevant and Appropriate Requirements
J. II. Baxter Stiperfund Site 1990 ROD
Standard, Requirement,
Criteria or Limitation
California Air Resources Act
Citation
Health & Safety Code, Div. 26
Sec. 39000
Description
Regulates both nonvehicular and vehicular
sources of air contaminants in California.
Comments
The local Air Pollution Control District
sets allowable discharge standards.
Emission from heavy equipment and
excavation dusts will need to comply
with APCD standards.
California Safe Drinking Water
Act
Porter Cologne Water Quality
Control Act
California Hazardous Waste
Control Laws
17 CCR, Part HI, Chapter 1,
Sec. 60000 et. seq.
Health & Safety Code,
Div. 5, Part 1, Chapter 7,
Sec. 4010 et. seq.
22 CCR, Div. 4, Chapter 15,
Sec. 64401 et seq.
Water Code, Div. 7, Sec.
13000 et. seq.
Health & Safety Code, Div.
20, Chapter 6.5, Sec. 25100 et
seq.
Regulations governing public water
systems. Drinking Water Quality Standards
- Maximum Contaminant Levels (MCLs),
Secondary Maximum Contaminant Levels
(SMCLs).
Establishes authorities of the State and
Regional Water boards to protect water
quality by regulating waste disposal and by
requiring cleanup of hazardous condition.
Regulations governing hazardous waste
control; management and control of
hazardous waste facilities; transportation;
laboratories; classification of extremely
hazardous, hazardous, and non-hazardous
waste.
CA regulatory agency is the Air
Resources Board. Local regulatory
agencies are the Air Pollution Control
Districts.
The Slate MCL of 1 ppb for benzene was
selected as a groundwater standard for
this site.
CA Regulatory Agency: Department of
Health Services, Sanitary Engineering.
The Basin Plan was used to establish
surface water discharge limitations and
sediment clean-up standards.
These regulations were used to establish
hazardous waste clean-up levels, facility
closure requirements, and requirements
for siting and construction of a wastt-
disposal facility.
CA Regulatory Agency: Department of
Health Services.
J.H Baxter
ROD Amendment
ARCS_Projrcls\Baxlei\T8J).1MARIX>C
I Of 2
March 26. 1998
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Table 8-3 (Continued)
California Applicable or Relevant and Appropriate Requirements
J. H. Baxter Superfund Site 1990 ROD
Standard, Requirement,
Criteria or Limitation
California Toxic Pits Cleanup
Act (TPCA)
State Action Levels
Citation
Health & Safety Code,
Sec. 25250 et. seq.
DHS Criteria
Criteria for Identification of
Hazardous and Extremely
Hazardous Wastes-Threshold
Limit Concentrations
22 CCR, Div. 4, Chapter 30,
Art. 11. Sec. 66693 et. seq.
Description
Regulates the closure of surface
impoundment's containing hazardous
waste.
Criteria setting chemical specific
concentration levels. Numerical limits
designed to protect human health from
chemical constituents in drinking water.
Recommended acceptable limits.
Action levels are drinking water exposure
criteria implemented throughout the state.
They are developed by DHS Sanitary
Engineering Branch to supplement Safe
Drinking Water Act standards.
Promulgated criteria to determine if a
material is hazardous. Includes Soluble
Threshold Limit Concentrations (STLCs)
and Total Threshold Limit Concentration
(TTLCs).
Comments
Several units identified by the
MCRWQCB are present at the site.
Several TPCA units present at site.
Applied Action Level of 2.2 ppb was
used to identify the clean-up standards
for pentachlorophenol.
California Regulatory Agency:
Department of Health Services; Sanitary
Engineering Branch.
TTLC and STLC criteria were used to
identify soil clean-up standards.
CA Regulatory Agency: Department of
Health Services.
Source: FFS Table 2-2
J II liuxk-i
KOI) AiiicMclmenl
AKCS l'n>|ivl>\H:ulcrVIH 01MAK IX»C
2 I.I 2
Miirch 2(>.
I'l lllll'll I'll Kl'l II It'll l
-------
Table 8-4
FEDERAL AND STATE APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS FOR
J.H. BAXTER ROD AMENDMENT
Source
Standard, Requirement,
Criteria or Limitation
Applicable or
Relevant and
Appropriate
Description of Standard, Requirement, Criteria or
Limitation
Manner in Which ARAR Applies;
Action, Location or Chemical Specific
ARAR
Porter-Cologne
Water Quality
Control Act
§§1058,
13140-47,
13260, 13263
and 13269; 23
CCR§§
25IO(a),
25ll(d)
The specific Title 23,
Chapter 15
requirements listed
below.
Relevant and
Appropriate
to the slurry
wall
containment
system;
applicable to
the RCRA-
equivalent
disposal cell
and the soil
staging and
fixation area.
Section 25IO(a) provides that the Chapter 15
regulations arc applicable to the water quality
aspects of discharges to land and establish waste
management requirements for specifically
enumerated waste management units. Section
2511 (d) provides that actions taken by or at the
direction of public agencies to clean up or abate
conditions of pollution resulting from
unintentional or unauthorized releases of waste or
pollutants to the environment are exempt from the
requirements of Chapter 15, provided that
remedial actions intended to contain such wastes
at the place of release are required to implement
applicable provisions of Chapter 15 to the extent
feasible, and provided that wastes removed from
the original place of release shall be discharged in
accordance with the requirements of Chapter 15,
Article 2.
Sections 2510(a) and 2511 (d) are the
sources of the Chapter 15 action specific
ARARs since they do not contain
prescriptive standards themselves. These
ARARs are relevant and appropriate,
rather than applicable, to the slurry wall
containment system because the slurry
wall containment system is not a "waste
management unit" as that term is defined
in Chapter 15. These ARARs are.
applicable to the RCRA-equivalcnt
disposal cell and the soil staging and
fixation area
J.H. Baxter
ROD Amendment
ARCS_Projccls\Baxter\T8_04M A R. DOC
I of II
March 26, 1998
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Table 8-4 (Continued)
FEDERAL AND STATE APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS FOR
J.H. BAXTER ROD AMENDMENT
Source
Standard, Requirement.
Criteria or Limitation
Applicable or
Relevant and
Appropriate
Description of Standard, Requirement, Criteria or
Limitation
Manner in Which ARAR Applies;
Action, Location or Chemical Specific
ARAR
Porter-Cologne
Walcr Quality
Control Act
§§1058,
13140-47,
13260, 13263
and 13269
23CCR§25IO(b)
Relevant and
Appropriate
to the slurry
wall
containment
system;
applicable to
the soil
staging and
fixation area.
Section 2510(b) authorizes discretionary use of
engineering alternatives in lieu of construction or
prescriptive standards where the construction or
prescriptive standard is not feasible, there is a
specific engineering alternative that is consistent
with the performance goal addressed by the other
standards and the engineering standard affords
equivalent protection against water quality
impairment to comply with Chapter 15
requirements.
The soil staging and fixation area and
the slurry wall construction zone comply
with this action specific requirement and
thereby comply with Chapter 15.
Porter-Cologne
Water Quality
Acl§§!058
and I3I72;23
CCR §2520(a)
23CCR
§2520(b)(2)(C);
§2520(c)
Relevant and
Appropriate
Wastes which if mixed or commingled with other
wastes produce violent reaction, heat or pressure,
fire or explosion, toxic byproducts or reaction
products which impair the integrity of containment
structures shall only be discharged at dedicated
waste management units that are designed and
constructed to contain such wastes. Dischargers
are responsible for accurate characterization of
wastes (e.g., determining whether they are
hazardous wastes), including compatibility with
containment features/other wastes.
Action specific ARAR that addresses
requirements relating to materials
compatibility in connection with me
construction of the slurry wall.
Porter-Cologne
Water Quality
Act §§1058.
13172 and
13360
23 CCR §2530(d)
Relevant and
Appropriate
Containment structures at waste management units
must have foundation/base capable of providing
support for structure and withstanding hydraulic
pressure gradients to prevent failure.
Action specific ARAR which addresses
construction requirements for slurry
wall.
J.H. Baxter
ROD Amendment
DOC
2 Of II
March 26, 1998
Printed on
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Table 8-4 (Continued)
FEDERAL AND STATE APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS FOR
J.H. BAXTER ROD AMENDMENT
Source
Standard, Requirement,
Criteria or Limitation
Applicable or
Relevant and
Appropriate
Description of Standard, Requirement, Criteria or
Limitation
Manner in Which ARAR Applies;
Action, Location or Chemical Specific
ARAR
Porter-Cologne
Water Quality
Act §§1058,
13172 and
13360
23CCR§253l(b)(2),
(c) and (d)
Relevant and
Appropriate
Sets prescriptive standards for Class I (hazardous
waste) waste management units. Addresses the use
of harriers to prevent lateral movement of fluid
(waste and leachatc), and design, construction,
operation and maintenance of waste management
units wilh respect to 100 ycur lloodplains and
geologic faults.
Action specific ARAR relating to the
design and construction of (he slurry
wall at the site.
Porter-Cologne
Water Quality
Act§§1058,
13172 and
13360
23 CCR §2540(a), (e)
and (I)
Relevant and
Appropriate
Prescribes general design and construction criteria
for Class I waste management units to prevent
migration of wastes to adjacent geologic materials,
ground water or surface water and requires
maintenance of integrity of containment structures.
Action specific ARAR relating to design
and construction of the slurry wall
containment system.
Porter-Cologne
Water Quality
Act §§1058,
13172 and
13360
23 CCR §2541 (a)
Relevant and
Appropriate
Requires that materials used in containment
structures have appropriate chemical and physical
properties to ensure that the structures do not fail to
contain waste due to pressure gradients, physical
contact with waste, chemical reactions with soil or
rock, climatic conditions, etc.
Action specific ARAR relating to the
materials to be used in constructing (he
slurry wall.
Porter-Cologne
Water Quality
Acl §§ 1058,
13172 and
13360
23 CCR §2541 (e) and
Table 4.1
Relevant and
Appropriate
Prescribes technical requirements for earthen
materials to be used in containment structures and
construction standards for waste management units
other than land treatment.
Action specific ARAR relating to design
and construction of the slurry wall
containment system.
J.H. Baxter
ROD Amendment
ARCS_Prujccls\BaalciVT8_04MAR.DOC
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March 26, 1998
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Table 8-4 (Continued)
FEDERAL AND STATE APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS FOR
J.H. BAXTER ROD AMENDMENT
Source
Standard, Requirement,
Criteria or Limitation
Applicable or
Relevant and
Appropriate
Description of Standard, Requirement, Criteria or
Limitation
Manner in Which ARAR Applies;
Action, Location or Chemical Specific
ARAR
Porter-Cologne
Water Quality
Act §§ 1058,
13172 and
13360
23CCR
§2545(a).(b)(l)-(3)
and (b)(S)
Relevant and
Appropriate
Prescribes requirements for subsurface barriers
(cutoff walls) used in conjunction with natural
geologic materials so that they meet lateral
permeability standards.
Action specific ARAR relating to design
and construction of the slurry wall.
provided that the keyed depth of the
cutoff walls may be reduced to three feel
with EPA approval in order to protect
the integrity of the Older Clastic
Assemblage.
Porter-Cologne
Water Quality
Act §§ 1058,
13172 and
13360
23 CCR §2546
Relevant and
Appropriate
Prescribes requirements for precipitation and
drainage controls for waste management units and
containment structures.
Action specific ARAR relating to the
design and construction of the slurry
wall containment system, including the
drainage controls to be built around the
exterior of the slurry wall.
Porter-Cologne
Water Quality
Act §§ 1058,
13172 and
13360
23 CCR §2547
Relevant and
Appropriate
Requires that Class I waste management units be
designed to withstand the maximum credible
earthquake without damage to the foundation or the
structures controlling leachate, surface drainage,
erosion, etc.
Action specific ARAR relating to the
design and construction of the slurry
wall containment system, including the
drainage controls to be built around the
exterior of the slurry wall.
J.H. Baxter
ROD Amendment
ijeclsVB axler\T8_04MAR.DOC
4 of II
March 26, 1998
Printed on Recy
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Table 8-4 (Continued)
FEDERAL AND STATE APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS FOR
J.H. BAXTER ROD AMENDMENT
Source
Standard, Requirement,
Criteria or Limitation
Applicable or
Relevant and
Appropriate
Description of Standard, Requirement, Criteria or
Limitation
Manner in Which ARAR Applies;
Action, Location or Chemical Specific
ARAR
Porter-Cologne
Water Quality
Acl§§ 1058,
13172
23 CCR §2580(a)
Relevant and
Appropriate
Requires classified waste management units to be
closed according to a closure plan providing for
continued compliance with applicable standards for
waste containment, precipitation and drainage
controls, as well as continued monitoring. Post
closure maintenance period shall extend as long as
wastes pose a threat to water quality.
Action specific ARAR for entire area
within slurry wall containment system
should closure occur ut some future
date; provided however, that any
requirement that is not consistent with
the surface soils remedy or the
institutional controls to be selected as
part of the ROD amendment will not be
considered ARARs.
Porter-Cologne
Water Quality
Acl§§ 1058,
13172, 13260
and 13267
23 CCR §2595
Relevant and
Appropriate
Requires analysis of how the ground and surface
water may affect the waste management unit and
how the unit may affect ground and surface water
in order to determine the suitability of the unit with
respect to ground water protection and avoidance
of geologic hazards.
Action specific ARAR for the design of
the slurry wall containment system.
J.H. Baxter
ROD Amendment
ARCS_Projecls\Baxler\T8_04MAR.DOC
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March 26, 1998
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Table 8-4 (Continued)
FEDERAL AND STATE APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS FOR
J.H. BAXTER ROD AMENDMENT
Source
Standard, Requirement,
Criteria or Limitation
Applicable or
Relevant and
Appropriate
Description of Standard, Requirement, Criteria or
Limitation
Manner in Which ARAR Applies;
Action, Location or Chemical Specific
ARAR
Porter-Cologne
Waler Quality
Act §§ 1058,
13172, 13260
and 13267
23CCR
§2597(a)(3),(5),(9),
(10), (b)(l),(2)
Relevant and
Appropriate
Sets forth requirements for closure and post closure
maintenance, including topographic map of Facility
to be closed, precipitation and drainage controls,
final cover and post closure land use. Requires
map with all proposed structures to be installed
over final landfill cover if the waste management
unit is to be used for purposes other than non-
irrigated open space during the post closure
maintenance period along with analysis of water
entering, leaving and remaining on-sile to ensure
integrity of final cover and monitoring system to
detect penetration of final cover.
Action specific ARAR for entire area
within slurry wall containment system
should closure occur ul some future
date, provided however, (hut uny
requirement that is not consistent with
the surface soils remedy or the
institutional controls to be selected as
part of the ROD amendment will not be
considered ARARs. The reporting
requirements are procedural and
therefore not ARAR.
Federal
Resource,
Conservation
and Recovery
Act Subtitle C,
42 U.S.C.
§6921 ctscq.
40 CFR §264.552 as
implemented through
22 CCR §66264.552
Applicable
Sets forth requirements for designating and
managing corrective action management units
(CAMUs) for the management of media containing
hazardous wastes otherwise subject to the RCRA
Land Disposal Restrictions (LDRs).
Action specific ARAR for the slurry
wall construction zone; the soil staging
and fixation area, and the RCRA-
equivalent disposal cell.
J.H. Baxter
ROD Amendment
AROtffcHeclii\Baxlet\T8_04MAR.DOC
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March 26, 1998
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Table 8-4 (Continued)
FEDERAL AND STATE APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS FOR
J.H. BAXTER ROD AMENDMENT
Source
Standard, Requirement,
Criteria or Limitation
Applicable or
Relevant and
Appropriate
Description of Standard, Requirement, Criteria or
Limitation
Manner in Which ARAR Applies;
Action, Location or Chemical Specific
ARAR
Federal
Resource
Conservation
and Recovery
Act Subtitle C,
42 U.S.C.
section 6921 el
seq.
40CFR261.20-
261.24 and 261.30-
261.33, as
implemented through
22 CCR 66261.20 -
66261.24, and
66261.30-662261.33
Applicable
Specifies the solid wastes which are subject to
regulation as listed hazardous waste and the solid
wastes subject to regulation as hazardous waste
based on hazardous characteristics.
Establishes the RCRA hazardous waslc
listing for wood processing wastes
(FO32, FO34 and FO35) and for wastes
which exhibit toxicity characteristics for
arsenic, chromium and
pcntachlorophenol (DOO4, DOO7
andDO37). Contaminated soils and
groundwater which exhibit a hazardous
characteristic or contain listed hu/.urdous
wastes must be managed as hazardous
waste.
Federal
Resource
Conservation
and Recovery
Act Subtitle C,
42 U.S.C.
section 6921 et
seq.
40 CFR 268.40 and 22
CCR 66268.40
Applicable
Specifies the treatment standards for wastes
restricted from land disposal.
Action specific ARAR for the
management of soils and groundwater
which exhibit a hazardous characteristic
(D004, D007 and D037) or contain
F032, F034 or F035 listed hazardous
waste. The RCRA land disposal
restrictions will apply to such
contaminated media, except for
contaminated media placed in a
designated area of contamination (AOC)
orCAMU.
J.H. Baxter
ROD Amendment
ARCS_Projecls\Baxler\T8_04MAR.DOC
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March 26, 1998
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Table 8-4 (Continued)
FEDERAL AND STATE APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS FOR
J.H. BAXTER ROD AMENDMENT
Source
Standard, Requirement,
Criteria or Limitation
Applicable or
Relevant and
Appropriate
Description of Standard, Requirement, Criteria or
Limitation
Manner in Which ARAR Applies;
Action, Location or Chemical Specific
ARAR
Federal Water
Pollution
Control Act,
§402; Porter-
Cologne Water
Quality Control
Act, Cal. Water
Code §§
13000, 13140
and 13240;
Water Quality
Control Plan
lor the North
Coast Region
(Basin Plan)
State Water Pollution
Control Board
(SWPCB) Resolution
68-16, Statement of
Policy With Respect
to Maintaining High
Quality Waters in
California
Applicable
Section 402 of the federal Water Pollution Control
Act, which sets up the National Pollutant Discharge
Elimination System program (NPDES), regulates
point source discharges into "waters of the United
States." The RWQCBs are the delegated
authorities in California to implement the NPDES
program. As applied to surface waters. Resolution
68-16, adopted by the NCRWQCB, implements the
"anti-degradation" requirement of the federal
Water Pollution Control Act. Resolution 68-16
requires that existing high ground and surface
water quality be maintained; it requires that
activities which produce waste and discharge to
existing high quality waters meet waste discharge
requirements that (I) result in the best practicable
treatment or control of the discharge necessary to
ensure that a pollution or nuisance will not occur
and (b) the highest water quality consistent with the
maximum benefit to the people of the Stale will be
maintained.
This is an action and chemical specific
ARAR with respect to the discharge of
treated ground and surface/storm water
to Beaughton Creek, a tributary to the
Shasta River, a water of the United
Stales. The substantive portions of
WDR 93-88 and Cease and Desist Order
93-87, adopted by the NCRWQCB,
implement Section 402 of the federal
Water Pollution Control Act (the
NPDES Program) and Resolution 68-16
by setting the best practicable (rcatmenl
of surface and ground water as set forth
below and allowing discharges to
Beaughton Creek on a limited basis:
Arsenic: less than 5 ug/l
Chromium: less than 5 ug/l
Copper: less than 5 ug/l
Zinc: less than 10 ug/l
PCP: less than .3 ug/l
TCP: less than .4 ug/l
Total PAHs: less than I ug/l
Dioxins: less than .000025 ug/l
EPA implements the substantive
requirements of the WDRs as AR ARs at
CERCLA sites.
J.H. Baxter
ROD Amendment
ARCJgfcjeets\BaxierYT8_04MAR.DOC
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March 26, 1998
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Table 8-4 (Continued)
FEDERAL AND STATE APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS FOR
J.H. BAXTER ROD AMENDMENT
Source
Standard, Requirement,
Criteria or Limitation
Applicable or
Relevant and
Appropriate
Description of Standard, Requirement, Criteria or
Limitation
Manner in Which ARAR Applies;
Action, Location or Chemical Specific
ARAR
Federal Water
Pollution
Control Act
§303; Porter-
Cologne Water
Quality Control
Act, Cal. Water
Code 13050(0;
Porter-Cologne
Water Quality
Control Act,
Cal. Water
Code §§
13000, 13140
and 13240
Water Quality Control
Plan for the North
Coast Region (Basin
Plan). Table 2-1
(Beneficial Uses in the
North Coast Region);
SWRCB Resolution
88-63, Sources of
Drinking Water Policy
Applicable
Table 2-1 sets forth the beneficial uses of the
waters of the state that may be protected against
water quality degradation. Resolution 88-63
specifies that, with certain exceptions, all surface
and ground waters of the State are considered to be
suitable, or potentially suitable, for municipal or
domestic water supply. Applies in determining
beneficial uses for waters that may be affected by
discharges of waste.
Location specific ARAR that identifies
beneficial uses of Shasta River and its
tributaries as Including municipal,
domestic, agricultural und industrial
supply, groundwater recharge,
freshwater replenishment, water contact
and non-contact recreation, warm and
cold freshwater habitat, wildlife habitat,
fish migration and spawning. In
addition, Resolution 88-63 applies
because the designated beneficial use of
Beaughton Creek includes municipal
and domestic water supply. These uses
form the basis for the treatment
standards for the effluent being
discharged into Shasta River and its
tributary, Bcaughton Creek.
Federal Water
Pollution
Control Act
§303; Porter-
Cologne Water
Quality Control
Act, Cal. Water
Code §13241
Water Quality Control
Plan for the North
Coast Region (Basin
Plan), Chapter 3
(Water Quality
Objectives)
Applicable
Water Quality Objectives form the basis for (he
establishment of waste discharge requirements and
discharge prohibitions necessary to protect the
present, probable and future beneficial uses
enumerated in Table 2-1 (above) and to protect
existing high quality waters of the State.
Location specific ARAR that identifies
water quality objectives for the Shasta
River and its tributary, Beaughlon
Creek. Objectives used as a basis for
adoption of substantive requirements of
Orders 93-87 and 93-88 pertaining to
discharges to Beaughlon Creek.
J.H. Baxter
ROD Amendment
ARCS_Projecis\BaxiertT8_04MAR.DOC
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March 26, 1998
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Table 8-4 (Continued)
FEDERAL AND STATE APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS FOR
J.H. BAXTER ROD AMENDMENT
Source
Standard, Requirement,
Criteria or Limitation
Applicable or
Relevant and
Appropriate
Description of Standard, Requirement, Criteria or
Limitation
Manner in Which ARAR Applies;
Action, Location or Chemical Specific
ARAR
Federal Water
Pollution
Control Act
§402; 40
C.F.R. Parts
122. 123 and
124
SWPCB Order No.
92-08-DWQ, NPDES
General Permit No.
CAS000002 (Waste
Discharge
Requirements Tor
Discharges of
Stormwater
Associated With
Construction Activity)
Applicable;
relevant and
appropriate to
construction
activities
affecting less
than five acres
Section 402(p) of the Federal Water Pollution
Control Act establishes a framework for regulating
industrial stormwatcr discharges under the NPDES
program. In November 1990, EPA published the
final regulations establishing storm water permit
requirements. Discharges of stormwatcr associated
with construction activity from soil disturbance of
more than five acres must be regulated as industrial
activity and covered by an NPDES permit. The
RWQCBs are the delegated authorities in
California to implement the NPDES program.
The substantive portions of the general
permit arc action specific ARARs for all
construction activities at the site,
including construction of the disposal
cell and construction activities
associated with the installation of the
slurry wall and the gravel drainage
trench.
Federal Water
Pollution
Control Act
§402; 40
C.F.R. Parts
122, 123 and
124
SWPCB Order No.
97-03-DWQ, NPDES
General Permit No.
CASOOOOOI (Waste
Discharge
Requirements for
Discharges of
Stormwaler
Associated With
Industrial Activities
Excluding
Construction
Activities)
Applicable
Section 402(p) of the Federal Water Pollution
Control Act establishes a framework for regulating
industrial stormwater discharges under the NPDES
program. In November 1990, EPA published the
final regulations establishing NPDES storm water
permit requirements for discharges of stormwatcr
associated with industrial activity. The RWQCBs
are the delegated authorities in California to
implement the NPDES program.
The substantive portions of the general
permit are action specific ARARs for
industrial activities relate to the remedy
such as equipment operation, and for
stormwater runoff (lowing over
contaminated surface soil at the site.
J.H. Baxter
ROD Amendment
_04MAR.DOC
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March 26, 1998
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Table 8-4 (Continued)
FEDERAL AND STATE APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS FOR
J.H. BAXTER ROD AMENDMENT
Source
Standard, Requirement,
Criteria or Limitation
U.S. EPA Office of
Solid Waste, "RCRA
Ground Waler
Monitoring: Draft
Technical Guidance,"
Nov. I992(EPA/530-
R-93-001)
Applicable or
Relevant and
Appropriate
Not an
ARAR, but
adopted by
EPA as
enforceable
performance
standard.
Description of Standard, Requirement, Criteria or
Limitation
Sets forth requirements for (he development and
implementation of a ground water monitoring
program.
Manner in Which ARAR Applies;
Action, Location or Chemical Specific
ARAR
Applies to (he development of a
comprehensive monitoring program for
the site.
J.H. Baxter
ROD Amendment
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Table 8-5
Comparative Costs of Alternatives ($1,000)
Slurry Wall/Ground Water
Remediation System Cost1
Total Incremental Cost
Above No Further Action
Baseline2
TOTAL(4)
ALTERNATIVE
1
$11,000
0
$11,000
ALTERNATIVE
2A3
$11,000
$26,000
$37,000
ALTERNATIVE
2B3
$11,000
160,000
$171,000
ALTERNATIVE
3
$11,000
1,300
$12,300
I. Total Project Cost from ROR. This cost also includes some supporting components of the remedial action that are implemented outside the Target Area.
2. From FFS Appendix E:
3. Alternative 2A costs are for (he minimum volume of soil removal; Alternative 2B costs are for the maximum volume of soil removal.
4. These costs represent the total costs for each alternative. The surface soils remedy is not included in these costs.
Source: FFS Table 6-4
J. H. Baxter
ROD Amendment
ARCS Projecls\BaxtertT8_05MAR.DOC
March 26, 1998
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Table 8-6
Nine Criteria Analysis for the Soil Cover Modification for Surface Soils Containing Inorganic
Concentrations Above Background and Below the 1990 ROD Subsurface Soil Excavation Standard
Criterion
Overall Protection of Human
Health and the Environment
Compliance with ARARs
Short-term Effectiveness
Protection of community
Protection of workers
Environmental impacts
Long-term Effectiveness and
Permanence
Magnitude of residual risk
Adequacy of controls
Reliability
Reduction of Mobility, Toxicity, or
Volume
Implementability
Technical feasibility
Administrative feasibility
Availability of services
Cost
State Acceptance
Community Acceptance
Discussion
An asphaltic concrete cover will prevent contact of surface water with
contaminated soils. Asphaltic concrete will also enhance surface runoff of
contaminated soil areas, minimizing or eliminating infiltration and potential
leaching of inorganic contaminants from surface soils into underlying soils
and shallow groundwater. The asphaltic concrete cover will prevent direct
dermal contact with surface soils containing contaminants of concern, and
eliminate the potential for accidental ingestion/inhalation. Combined with
institutional controls to protect the integrity of the cover and to prevent
human exposure to waste left in place, this proposed modification will be
sufficiently protective of human health and the environment to meet the
remedial action objectives for the site.
This modification complies with ARARs.
Little or no handling of the contaminated soils will be required. Some
grading may be necessary to provide an appropriate surface for the asphaltic
concrete surfacing. Use of asphaltic paving will entail use of standard
construction practices for the placement of paving over impacted soils.
Short-term effectiveness will therefore be improved with this modification
of the remedial action for surface soils contaminated with inorganics.
No reduction in permanence will occur with this change in remedial action.
With routine maintenance and appropriate institutional controls, the level of
effectiveness and permanence will be sufficiently protective of human
health and the environment to meet the remedial action objectives of the
site.
Reduction of mobility of all inorganic contaminants will be achieved for all
those soils which will be covered with asphaltic concrete paving. The
reduction will be achieved by preventing wind erosion, and minimizing or
eliminating surface water runoff from contacting the contaminated soils,
reducing infiltration.
This alternative is readily implementabie. There are no technical or
administrative factors which would preclude implementation of the
proposed remedial actions.
Elimination of the excavation step and the placement of two feet of
covering soil may offset the cost of the asphaltic pavement. However, the
difference in the cost of these two options is expected to be relatively low.
This modification is acceptable to the State.
This modification is acceptable to the community.
J. H. Baxter
ROD Amendment
ARCS_Projects\Baxler\T8_06MAR.DOC
March 26, 1998
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Table 8-7
Nine Criteria Analysis for Modification of Procedure to Verify
Attainment of Soils Treatment Standard for Soils Placed in RCRA-Equivalent Disposal Cell
Criterion
Overall Protection of Human
Health and the Environment
Compliance with ARARs
Short-term Effectiveness
Protection of community
Protection of workers
Environmental impacts
Long-term Effectiveness and
Permanence
Magnitude of residual risk
Adequacy of controls
Reliability
Reduction of Mobility, Toxicity, or
Volume
Implementability
Technical feasibility
Administrative feasibility
Availability of services
Cost
State Acceptance
Community Acceptance
Discussion
Although this test procedure is less conservative that the test using a citric
acid buffer, because it realistically represents the conditions at the site, the
change in test procedure will still provide appropriate overall protection of
human health and the environment.
This modification complies with ARARs. It is not required to comply with
RCRA Land Disposal Restrictions (LDRs) because the treated soils will be
placed in a Corrective Action Management Unit (CAMU).
Although the excavation standard and the leachate procedure used to
measure compliance have not been changed, the extent of the soil treatment
may be reduced somewhat, reducing the amount of soil handling required
during implementation of the remedy. Short-term effectiveness may
therefore be improved with this modification of the remedial action for
surface soils contaminated with inorganics.
Although this test procedure is less conservative that the lest using a citric
acid buffer, because it realistically represents the conditions at the site, there
will be no change in the long-term protectiveness and permanence as a
result of this change in test procedure.
Because this test procedure realistically represents the conditions at the site,
this change in the testing procedure will not result in any change in the
reduction of mobility, loxicity or volume of hazardous materials at the site.
This alternative is readily implementable. There are no technical or
administrative factors which would preclude implementation of the
proposed remedial actions.
Changing the treatment standard evaluation to use deionized water instead
of a citric acid buffer should reduce the extent of treatment required prior to
placement in lined cells. The reduction in the overall cost will be
proportional to the reduction in the treatment required to meet the standard.
The estimated cost savings is approximately $ 210.000. (TRC, 1998)
This modification is acceptable to the State.
This modification is acceptable to the community.
J. H. Baxter
ROD Amendment
ARCS_Projects\Baxier\T8_07MAR.DOC
March 26, 1998
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Table 8-8
Nine Criteria Analysis for Modification of Biotreatment Implementation
Criterion
Overall Protection of Human
Health and the Environment
Compliance with ARARs
Short-term Effectiveness
Protection of community
Protection of workers
Environmental impacts
Long-term Effectiveness and
Permanence
Magnitude of residual risk
Adequacy of controls
Reliability
Reduction of Mobility, Toxicity, or
Volume
Implementability
Technical feasibility
Administrative feasibility
Availability of services
Cost
State Acceptance
Community Acceptance
Discussion
If properly controlled and monitored, bioremediation in situ using natural
microbial populations may achieve the same results as bioremediation in
landfarming cells, and potential leaching of organic contaminants from
surface soils into underlying soils and shallow groundwater can be
adequately controlled. Overall protection of human health and the
environment would be essentially the same as that obtained using lined
remediation cells; e.g., for soils placed outside lined cells, the organic
materials would not be expected to leach into the groundwater at the levels
present after treatment. Because no liner is present, there may be some
short-term risk to the environment. The extent of this potential risk is
limited because the final disposition of the soils being bioremediated is the
RCRA -equivalent cell.
This modification complies with ARARs.
In situ bioremediation would reduce the amount of handling of
contaminated soils required, reducing the short-term exposure risks. Short-
term effectiveness would therefore be improved with this modification of
the remedial action for surface soils contaminated with organics. However,
the extent to which the remediated soil is moved, and the condition of that
soil may increase the short-term risk for materials handling.
In situ bioremediation is expected to achieve the same level of treatment as
that obtained by remediation in lined landfarm cells. There may be some
potential reduction in permanence due to the absence of a liner beneath
treated soils. The extent of this reduction in permanence would be
dependent in pan on the extent of remediation obtained. The final
disposition of the soils being bioremediated is the RCRA-equivalent cell.
The same reduction of toxicity and volume of organic contaminants is
expected to be achieved for in situ bioremediation as would be achieved for
bioremediation in lined landfarm cells. The reduction of mobility is
expected to be the same, base on results to date, but could be somewhat
lower, depending on the ability to control the bioremediation process.
This alternative is implementable, and would require methods nearly
identical to bioremediation in lined cells. The success of the treatment
technology will depend on the ability to adequately introduce the microbial
populations into the in situ soils with sufficient nutrients and fertilizers to
provide effective remediation while generating minimal or no leachate.
There are no administrative factors which would preclude implementation
of this proposed remedial action.
Elimination of the initial excavation step and the construction of lined
landfarm cells that would otherwise have been used during bioremediation
will reduce the cost of implementing this remedial action.
This modification is acceptable to the State.
This modification is acceptable to the community.
J. H. Baxter
ROD Amendment
ARCS_Projects\Baxter\T8_08MAR.DOC
March 26. 1998
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Table 8-9
Nine Criteria Analysis for Alternative Treatment
and Disposal Options for Area B Soils
Criterion
Overall Protection of Human
Health and the Environment
Compliance with ARARs
Short-term Effectiveness
Protection of community
Protection of workers
Environmental impacts
Long-term Effectiveness and
Permanence
Magnitude of residual risk
Adequacy of controls
Reliability
Reduction of Mobility, Toxicity, or
Volume
Implementability
Technical feasibility
Administrative feasibility
Availability of services
Cost
State Acceptance
Community Acceptance
Discussion
If the technology is successful, it will meet remedial action goals for soils
and will be protective of ground water. Surface soil protection is the same as
described in the September 25, 1990 ROD (IxlO'6 level for carcinogenic
PAHs).
This alternative will comply with ARARs.
Risk for workers lower than previous options in the September 25, 1990
ROD because little or no excavation of soils is required if in situ treatment
alternative is effective. Level of toxicity of the soils from organics would
be significantly reduced if the treatment standards can be achieved for most
of the soils remediated.
Some potential reduction in permanence with the elimination of the lined
cells for most of the treated soils. However, the level of effectiveness and
permanence will be the same as for all soils left in place, since the Area B
cleanup standards are as protective as those used to evaluate the need for
excavation and treatment of other soils contaminated with organics at the
site.
Reduction of mobility, toxicity, and volume of organic contaminants will
occur through in situ treatment. If the Area B soils can not be treated in situ
to levels that are protective of ground water, reduction of mobility, toxicity,
and volume will occur by excavation and disposal in the RCRA-equivalent
cell.
Treatability studies are required to determine the effectiveness of the
bioventing alternative. There are no administrative factors which would
preclude implementation of the proposed remedial actions.
Elimination of excavation and the lined treatment cells will significantly
reduce treatment and materials handling costs. The ability to leave soils in
place will eliminate the cost of excavation and disposal in a RCRA-
equivalent cell.
This modification is acceptable to the State.
This modification is acceptable to the community.
J. H. Baxter
ROD Amendment
ARCS_Projecis\Baxter\T8_09MAR.DOC
March 26, 1998
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TaBlTS-lO
Seven Criteria Analysis for Designation of the RCRA-equivalent Disposal Cell, the
Slurry Wall Construction Zone, and the Soil Staging and Fixation Area as
RCRA Corrective Action Management Units (CAMUs)
Criterion
Evaluation
(I)
The CAMU must facilitate the
implementation of reliable,
effective, protective, and cost
effective corrective action
measures.
Designation of the of the RCRA-equivalent disposal cell as a CAMU will facilitate the on-site
treatment and disposal of contaminated soils while ensuring that the remedy remains protective. The
CAMU designation will enable the use of Site-specific tests to measure compliance with treatment
standards and will thereby enhance the cost-effectiveness of the remedy by reducing the volume of
soils requiring treatment while maintaining an equivalent level of protection. The RCRA-equivalenl
disposal cell will comply with the RCRA and Chapter 15 design, construction, operation, closure and
postclosure requirements for landfills identified in Table 8-11, and will thereby effectively and reliably
contain contaminated soils.
Designation of the soil staging and fixation area as a CAMU will facilitate the implementation of the
slurry wall construction and will facilitate the excavation and treatment of contaminated soil by
providing a temporary place to safely stockpile soils. This CAMU will remain protective of human
health and the environment because is has required features (see Table 8-12) that will contain wastes
reliably, effectively and temporarily (one year). The stockpiled soils will be treated prior to disposal in
a RCRA- equivalent disposal cell. Being that is a temporary structure, the soils staging and fixation
area will be more cost effective than building a permanent facility that would require more complex
structure. It will ultimately be protective because upon completion of said treatment activities (one
year) all contaminated equipment, structures and soils in the soil staging and fixation urea will be
excavated and disposed of, or decontaminated, followed by construction of an asphalt cap.
Designation of the slurry wall construction zone as a CAMU will facilitate the construction of the
slurry wall. Thorough mixing of the slurry compound and soil before placement is required to insure
the protectiveness, reliability, and efficacy of the wall. The integrity of the wall is dependent on this
process, and the handling of these large volumes of soil must take place above ground to be cost-
effective or even feasible. Placement of the slurry mixture in the trench is necessary to form the
structure of the slurry wall, which will create an underground barrier to contain DNAPLs and
contaminated groundwater in the shallow aquifer.
J.H. Baxter
ROD Amendment
ARCS_Projects\BaxteiYT8_IOMAR.DOC
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March 26, 1998
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Table 8-10 (continued)
Seven Criteria Analysis for Designation of the RCRA-equivalent Disposal Cell, the
Slurry Wall Construction Zone, and the Soil Staging and Fixation Area as
RCRA Corrective Action Management Unit s (CAMUs)
Criterion
Evaluation
(2) Waste Management activities
associated with the CAMU shall
not create unacceptable risks to
humans or the environment.
The RCRA equivalent disposal cell will be operated and maintained in accordance with the RCRA
and Chapter 15 requirements set forth in Table 8-11 and will therefore be protective of human health
and the environment. The soil staging and fixation area will be operated and maintained in accordance
with RCRA and Chapter 15 requirements set forth in Table 8-12 to prevent leachate generation, wind
dispersal and general surface contact. Therefore it will not create an unacceptable risk to humans or
the environment.
The slurry wall construction zone will be handling soils that are mostly uncontaminated. The small
volume of soil that might contain some low levels of contaminants will be exposed in the TI zone for a
very short period of time due to the short slurry wall construction process. Waste management
activities associated with the slurry wall construction process will therefore be protective of human
health and the environment.
(3) The CAMU shall incorporate
uncontaminated areas only if the
inclusion of such areas allows
better protection.
The RCRA-equivalent disposal cell will be located in an uncontaminated area of the Site. Creation of
a single disposal cell in an isolated area of the Site will reduce the possibility of damage to the cell
from ongoing plant operations and will simplify long-term maintenance of the cell cover. In addition,
this location will reduce worker exposure to contaminated soils during the construction of the cell
"bottom" (i.e. the soil berms, vadose zone monitoring system and bottom liners).
The soil staging and fixation area is underlain by both contaminated and uncontaminated soils.
Incorporating uncontaminated areas of the Site will facilitate the location of the soil staging and
fixation area where it will not be disturbed by ongoing plant operations. In addition this location will
facilitate placement of soils into the RCRA cell because it is in proximity to both the areas where soils
will be excavated and the RCRA-equivalent disposal cell. Closure of the soil staging and fixation area
includes excavation of all contaminated soils, followed by construction of a protective asphalt
covering. Most of the slurry wall construction zone will be within the TI zone and therefore not in an
uncontaminated area. Locating part of the construction zone in an uncontaminated area is necessary to
insure proper mixing of the slurry compound and soil to guarantee proper construction of the wall,
which will in turn allow better protection.
TTOS
. Baxter
Amendment
_Projecis\BaxicrVT8_IOMAR.DOC
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March 26, 19'
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Table 8-10 (continued)
Seven Criteria Analysis for Designation of the RCRA-equivalent Disposal Cell, the
Slurry Wall Construction Zone, and the Soil Staging and Fixation Area as
RCRA Corrective Action Management Unit s (CAMUs)
Criterion
Evaluation
(4)
Areas within the CAMU, where
wastes remain in place after
closure of the CAMU, shall be
managed and contained so as to
minimize the potential for future
releases.
The RCRA-equivalent disposal cell will be closed and maintained in accordance with the RCRA
landfill closure and post-closure requirements set forth in Table 8-11. The RCRA-equivalent cell will
be capped to prevent future releases. Long-term maintenance of the cap and the RCRA-equivalent cell
containment features as well as groundwater monitoring will ensure that the RCRA-equivalent cell
does not release contaminants to soils and groundwater. No wastes will remain in place at the soil
staging and fixation area or in the above-ground slurry wall platform.
Any contaminated soil incorporated into the structure of the slurry wall will be contained and
immobilized by the matrix of the slurry wall, minimizing the potential for future release.
(5)
The CAMU shall expedite the
implementation of corrective
action measures.
The RCRA-equivalent disposal cell will expedite the implementation of the remedy because on-site
disposal of contaminated soils will be both faster and more protective than off-site treatment and
disposal. On-site disposal will require soils to be transported only once and will thereby reduce worker
exposure during handling as well as off-site residents' exposure to contaminated wind-blown dust.
The CAMU designation will also expedite the implementation of the remedy by reducing the amount
of soil requiring treatment while maintaining an effective level of protection.
The construction at this site is to take place during two major phases. The phases have been
established based on the limited window of time available for construction, because the site is still an
operating facility. The soil staging and fixation area will hold contaminated soils excavated during the
first phase of construction that await disposal once the RCRA-equivalent disposal cell is constructed
in the second phase. Fixation of soils that do not meet the modified leachate test will take place here,
expediting the disposal of soils once the RCRA-equivalent disposal cell in constructed.
Without the slurry wall construction zone, construction of the slurry wall would not be possible. The
CAMU will expedite the implementation of the corrective action measures by permitting the
implementation of the only feasible method to construct the slurry wall.
J.H. Baxter
ROD Amendment
ARCS_Projects\BaxtertT8_IOMAR.DOC
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March 26. 1998
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Table 8-10 (continued)
Seven Criteria Analysis Tor Designation of the RCRA-equivalent Disposal Cell, the
Slurry Wall Construction Zone, and the Soil Staging and Fixation Area as
RCRA Corrective Action Management Unit s (CAMUs)
Criterion
Evaluation
(6)
The CAMU shall enable the use
of treatment technologies to
enhance long term effectiveness
of corrective actions by reducing
the toxicity, mobility or volume
of wastes.
The use of the selected remedial actions of bioremediation and stabilization will reduce the volume,
toxicity and mobility of the wastes to be stored in the RCRA-equivalent disposal cell CAMU at the
Baxter site.
The soil staging and fixation area CAMU, a temporary feature, will facilitate the stabilization activity
that will reduce the and mobility of the wastes in the RCRA-equivalent disposal cell.
The slurry wall will reduce the mobility of wastes in the groundwater within the slurry wall, and will
enhance the remediation of groundwater outside the DNAPL zone. Extraction and treatment will
reduce the toxicity and volume of the wastes in the groundwater outside the DNAPL zone.
(7)
To the extent practicable, the
CAMU shall minimize the land
areas where wastes will remain
in place after closure of the
CAMU.
The RCRA-equivalent disposal cell will enable excavated soils from various parts of the Site to be
contained in one location, thereby reducing the land areas where wastes will remain in place after
closure. In addition, in situ bioventing of organics-contaminated soils in Area B, if successful, will
significantly reduce the amount of contaminated soils left in place at the Site upon closure of the
RCRA-equivalent cell.
No wastes will remain in place at the soil staging and fixation area.
No wastes will remain in the above ground slurry wall working platform. A small portion of the slurry
wall will contain contaminated soil fixed in the matrix of the wall.
J.H. Baxter
> Amendment
R_Projecu\BaxtertT8_IOM^.DOC
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March 26. 199,
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Table 8-11
Design, Operation, Closure, and Post-closure
Requirements for RCRAa-equivalent Disposal Cell
Citation
Requirement
40 CFRb §264.18 as implemented through
22 CCRC §66264.18; 23 CCR 2531(c)-(f).
Requires that new facilities not be located within 61
meters (200 feet) of a fault which has been
displaced in Holocene time. In addition, a landfill
may not be located in a floodplain subject to a 100-
year return period or in areas subject to rapid
geologic change or tidal waves.
40 CFR §264.30 l(a)(l)(i) & (iii) and
§264.301(c) as implemented through
22 CCR §66264.30 l(a)(l)(A) & (C) and
§66264.301 (c); 23 CCR §2542.
Design standards for the liner system, the leachate
collection and removal systems, and leak detection
systems.
40 CFR §264.30l(a)(l)(ii) as implemented
through 22 CCR §66264.30l(a)(l)(B).
Requires foundation or base capable of providing
adequate support to prevent liner failure.
40 CFR §264.301 (g)-(i) as implemented
through 22 CCR §66264.30l(f)-(h).
Construction of a run-on control and run-off
management system, management of collection and
holding facilities associated with such systems.
40 CFR §264.301(j) as implemented
through
22 CCR §66264.301 (i); 23 CCR §2544(a)
and (b).
Interim and final cover to control wind dispersal of
paniculate matter. Interim cover to minimize
percolation of precipitation through wastes.
40 CFR §264.303(a) as implemented
through
22 CCR §66264.303(a).
During and immediately after construction or
installation, liners must be inspected to ensure that
they meet the standards.
40 CFR §264.14 as implemented through
22 CCR §66264.14
Security requirements during construction and
operation.
40 CFR §264.314 as implemented
through 22 CCR §66264.314; 22 CCR
§66264.318.
Requirements for management of liquid and
nonliquid waste.
40 CFR §264.15 and §264.303(b) as
implemented through 22 CCR §66264.15
and §66264.303(b).
Requirements for inspection during operation of
landfill.
40 CFR §264.310(a) as implemented
through 22 CCR §66264.310(a)
Requirements for the design and construction of the
landfill cover.
J.H. Baxter
ROD Amendment
ARCS_Projccis/Baxier/02_rodafr8_IIMAR.DOC
1 Of 2
March 26, 1998
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Table 8-11 (Con't)
Design, Operation, Closure, and Post-closure
Requirements for RCRA-equivalent Disposal Cell
Citation
Requirement
40 CFR §264.25 as implemented through
22 CCR §66264.25.
Landfill and cover must be designed to withstand
maximum credible earthquake and 24-hour
probable maximum precipitation.
40 CFR §264.117 and §264.310(b)-(d) as
implemented through 22 CCR §66264.117
and 22 CCR §66264.310(b)-(d).
Requirements for closure and post-closure care and
maintenance of the landfill.
40 CFR §264.112 and §264.118 as
implemented through 22 CCR §66264.112
and 22 CCR §66264.118.
Requires written closure and post-closure plan.
40 CFR §264.91 (a), §264.94, §264.97, and
§264.98 as implemented through 22 CCR
§66264.91 (a), §66264.94, §66264.97 and
§66264.98; 22 CCR §66264.700.
Requirements for detection and evaluation
monitoring, including monitoring of soil pore
liquids, to ensure that the landfill does not release
any contaminants to groundwater. Requirements for
monitoring to ensure that the landfill does not
release any contaminants to air or soil.
Notes:
a RCRA - Resource Conservation and Recovery Act
b CFR - Code of Federal Regulations
c CCR - California Code of Regulations
J.H. Baxter
ROD Amendment
ARCS_Projects/Baxier/02_roda/T8_l IMAR.DOC
2 Of 2
March 26, 1998
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Table 8-12
DESIGN, OPERATION, CLOSURE AND POST-CLOSURE
REQUIREMENTS FOR THE SOIL STAGING AND FIXATION AREA CAMU
Citation
Requirement
a /~u b
Title 23 CCR8, Ch.° 15, §2544(c)
Requires an interim cover to minimize
percolation through wastes.
Title 23 CCR, Ch. 15, §2546(0
Requires cover material to be graded to divert
precipitation from waste piles.
Title 23 CCR, Ch. 15, §2542(c)
Requires a synthetic liner with a minimum
thickness of 40ml.
Title 23 CCR, Ch. 15, §2530(c)
Requires siting, design, construction, and
operation of waste piles to be a minimum of 5
feet above highest anticipated elevation of
underlying ground water.
Title 23 CCR, Ch. 15, §2540(a)
Requires prevention of waste migrating from
the waste piles to adjacent areas, ground water
or surface water.
Title 23 CCR Ch. §2531(c)-(f)
Requires that waste management unit not be
located within 200 feet (61 meters) of a fault
which has been displaced in Holocene times. In
addition, the unit must not be located in a
floodplain or must be designed, constructed,
operated and maintained to prevent washout by a
100-year flood. The unit must not be located in
areas subject to rapid geologic change or tidal
waves.
Title 23 CCR Ch. §2547
Requires the waste management unit to
withstand an earthquake without damage to
leachate control, surface drainage, erosion or
gas.
Title 23 CCR, Ch. 15 §2542(d)
Requires liner to cover entire area likely to be in
contact with wastes.
40 CFRC §264.258(a) as implemented
through CCR §66264.258(a)
Requires wastepile to be excavated for closure.
J.H. Baxter
ROD Amendment
ARCS_Projects/Baxter/02_roda/T8_l 2MAR.DOC
Iof2
March 26, 1998
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Table 8-12 (Continued)
DESIGN, OPERATION, CLOSURE AND POST-CLOSURE
REQUIREMENTS FOR THE SOIL STAGING AND FIXATION AREA CAMU
Citation
Requirement
40 CFR §2646.15(a), as implemented
through CCR 66264.15(a)
Requires inspection of waste piles for discharge
or release of hazardous waste, and that action
will be taken to remedy any deterioration or
leakage of the waste piles.
40 CFR §264.14(a) and (c) as implemented
through CCR 66264.14(a) and (c)
Requires prevention of unauthorized access to
the waste piles, and posting of signs alerting
unauthorized personnel to keep out.
Notes:
a CCR - California Code of Regulations
b Ch.- Chapter
c CFR - Code of Federal Regulations
J.H. Baxter
ROD Amendment
ARCS_Projects/Baxler/02_roda/T8_ 12MAR.DOC
2 of 2
March 26. 1998
Printed on Recycled Paper
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FIGURES
-------
ANGEL VALLEY
SUBDIVISION
J. H. BAXTER
SUPERFUND SITE
J.H. BAXTER
PROPERTY
Approximate Scale in Feet
SAN FRANCISCO
J. H. BAXTER
SUPERFUND SITE
SITE LOCATION MAP
FIGURE 1-1
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FIGURE 8-1
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