PB99-964604
                              EPA541-R99-059
                              1999
EPA Superfund
      Record of Decision:
\
      Hanford Site-100 Area (USDOE)
      100-KR-2 OU
      Benton County, WA
      9/17/1999

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                   DECLARATION OF THE RECORD OF DECISION
  SITE NAME AND LOCATION

  USDOE Hanford 100 Area EPA ID# WAS 890090076
  100-KR-2 Operable Unit
  Hanford Site
  Benton County, Washington

  STATEMENT OF BASIS AND PURPOSE

 The State of Washington concurs with the selected remedy.

 ASSESSMENT OF SITE
                                     °f Decisi°n CROD) is necessary to protect the public
                                    actual or ""— " releases
DESCRIPTION OF SELECTED REMEDY

The selected remedy is an interim remedial action to mitigate the potential to release hazardous
SlSadeFdTr ^ 1K BaSinS' * ^ ^inS' ^ SNF WiU be loaded into baskets' the
tn^h! r  M v     multi-canister overpacks, removed from the K Basins and transported
to the Cold Vacuum Drymg (CVD) facility located in the 100 K Area This interim
        aWie C°ed upon receipt at ^ CVD- althou^ itSS^t
              nd       H       upon receipt at ^ CVD- aou   t
      the fuel will be dried at the CVD, then transported to the 200 Area of Hanford for

      steS^tio  f St° ?Se ^ ^ CanlSter St°rage Buildmg' ^ ultima£ely ^osed off-
      site at the national geologic repository.
     arnrT^ 'T *" K BaSiDS  ^ Sludse Wlli be seParated in'° transuranic (TRU)
     and non-TRU fractions as it is removed to the extent practicable.

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               The description in this ROD is based on the assumption that the majority of the
               sludge will be TRU and will be transferred to a permitted storage and treatment
               facility in the 200 Area. The interim remedial action will be completed upon
               receipt at the sludge storage and treatment facility, although it is expected that the
               TRU sludge will then be managed with other Hanford TRU waste and ultimately
               disposed off-site at the Waste Isolation Pilot Plant.
               Non-TRU sludge will be transported to the Environmental Restoration Disposal
               Facility (ERDF) located in the 200 Area, treated to meet the waste acceptance
               criteria, and disposed. .
  *     Treat and remove water from the K Basins. Water treatment at the K Basins will be
        done using the Integrated Water Treatment System (IWTS) during operations as well as
        pre-treatment prior to water removal from the basins.  After pre-treatment in the basins
        the water will be pumped into tanker trucks and transported to the Effluent Treatment
        Facility (ETF) hi the 200 Area. The interim remedial action will be completed upon
        receipt at the ETF, although it is expected that water will then be further treated at the
        ETF and disposed at the State Approved Land Disposal Site also located in the 200 Area.
  *     Remove debris from the K Basins.  The debris will be treated as needed to meet the
        waste acceptance criteria of the storage or disposal facility and transported to storage or
        disposal facilities. Treatment may occur at the K Basins, at a separate debris treatment
        facility, or at the storage or disposal facility. It is anticipated that most of the waste will
        be disposed of at the ERDF. Debris that does not meet waste acceptance criteria for
        ERDF will be stored in an existing permitted facility in the 200 Area.  Debris storage in
        the 200 Area is beyond the scope of the interim remedial action.
  *     Deactivate the basin.  Material removed will be disposed as debris.
  *     Institutional Controls. The DOE will  maintain or implement access  restrictions to
       prevent public access until final remedial action is completed.

Retrieval of SNF, sludge, debris, and water from the basins; basin deactivation; and treatment
within the scope of this interim remedial action will be designed by the DOE. The DOE will
incorporate the design into the Remedial Design Report / Remedial Action Work Plan
(RDR/RAWP). Treatment, storage, and disposal facilities will be identified in the RDR/RAWP.
The RDR/RAWP is subject to approval by the U.S.  Environmental Protection Agency (EPA).
Subsequent actions under CERCLA will remediate the basins and releases of hazardous
substances to the underlying soil and groundwater and constitute the final remedy for the site.

STATUTORY DETERMINATIONS

This interim remedial action is protective of human health and the environment, complies with
Federal and State applicable or relevant and appropriate requirements directly associated with
this action, and is cost-effective. This interim remedial action utilizes permanent solutions and
alternative treatment technologies to the maximum extent practicable, given the limited scope of
the interim remedial action.  This interim remedial action complies with the statutory preference
for remedies that employ treatment that reduces toxicity, mobility, or volume of contaminants as
a principal element. Subsequent actions are planned to fully address the threats posed by this
operable unit.

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 Because this remedy will result in hazardous substances, pollutants, or contaminants remaining
 on-site above levels that allow for unrestricted use and unrestricted exposure, a statutory review
 will be conducted within five years after initiation of remedial action to ensure that the remedy
 is, or will be, protective of human health and the environment. Because this is an interim
 remedial action, review of this operable unit and the remedy will be ongoing as the DOE, EPA,
 and Washington State Department of Ecology continue to develop and implement final remedial
 alternatives for the operable unit and the 100 Area National Priority List (NPL) site.

 The preamble to the NCP indicates that when non-contiguous facilities are reasonably close to
 one another and wastes at these sites are compatible for a selected treatment or disposal
 approach, CERCLA Section  104(d)(4) allows the lead agency to treat these related facilities as
 one site for response purposes and, therefore, allows waste transfer between such non-contiguous
 facilities without having to obtain a permit. The 100-K Area and the 200 Area are treated as one
 site for response purposes for this interim remedial action. This is consistent with all previous
 Hanford 100 Area RODs which required transfer of waste to the 200 Area.

 DATA CERTIFICATION CHECKLIST

The following information is included in the Decision Summary section of this ROD. Additional
information can be found in the Administrative Record file for this site.

 *      Chemicals of concern (COCs) and their respective concentrations (see Section VQ)
 *      Baseline risk represented by the COCs (see Section VET)
 *      Cleanup levels established for COCs and the basis for the levels is beyond the scope of
       this interim remedial action (see Section IV and VI)
 *      Current and future land and ground-water use assumptions used in the baseline risk
       assessment and ROD are not included in this ROD because they are beyond the scope of
       this interim remedial action (see Section VI)
 *      Land and groundwater use that will be available at the site as a result of the Selected
       Remedy are not included in this ROD because they are beyond the scope of this interim
       remedial action (see Sections IV and VI)
 *      Estimated capital, operation and maintenance (O&M), and total present worth costs;
       discount rate; and the number of years over which the remedy cost estimates are projected
       (see Section 10.7 and tables 9-1, and 10-1  for cost information. See Section 10.5 for
       schedule)
 *      Decisive factor(s) that led to selecting the remedy (i.e., describe how the Selected
       Remedy provides the best balance of tradeoffs with respect to the balancing and
       modifying criteria) (see Section X and the EIS discussion in Section II)
                                          111

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 Signature sheet for the Record of Decision for the USDOE Hanford 100-KR-2 Operable Unit K
 Basins Interim Remedial Action between the United States Department of Energy and the United
 States Environmental Protection Agency, with concurrence by the Washington State Department
 of Ecology.
Keith Klein
Manager, Richland Operations Office
United States Department of Energy
Date
                                        IV

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Signature sheet for the Record of Decision for the USDOE Hanford 100-KR-2 Operable Unit K
Basins Interim Remedial Action between the United States Department of Energy and the United
States Environmental Protection Agency, with concurrence by the Washington State Department
of Ecology.
Chuck Clarke                           ~~  	   Date
Regional Administrator, Region 10
United States Environmental Protection Agency

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Signature sheet for the Record of Decision for the USDOE Hanford 100-KR-2 Operable Unit K
Basins Interim Remedial Action between the United States Department of Energy and the United
States Environmental Protection Agency, with concurrence by the Washington State Department
of Ecology.
Michael Wilson              ,                              Date
Program Manager, Nuclear and Mixed Waste Program
Washington State Department of Ecology
                                        VI

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 1     Paths for Management of Waste Stored in the K Basins
 2     Hanford Site .......... ..............
 3     100-K Area with K Basins ...  ........ "
9-1   Alternatives Cost from Feasibility Study
10-1  K Basins Project Cost ....... .
                             GLOSSARY
                          TABLE OF CONTENTS

                DECLARATION OF THE RECORD OF DECISION

  SITE NAME AND LOCATION . .
  STATEMENT OF BASIS AND PURPOSE  ........................................ ?
  ASSESSMENT OF SITE  ...........      ..................................... !
  DESCRIPTION OF SELECTED REMEDY ..................... .................... *
  STATUTORY DETERMINATIONS .            ................................ -1
  DATA CERTIFICATION CHECKLIST ........... '.'.'.'.'.'.'.'.I'.'.'.'. .................. --•

                              ACRONYMS

                          DECISION SUMMARY

 I.    SITE NAME, LOCATION, AND BRIEF DESCRIPTION                      i
 H.   SITE HISTORY AND ENFORCEMENT ACTIVITIES    ...................... 9
 HI.   COMMUNITY PARTICIPATION .............      ....................... y
 IV.   SCOPE AND ROLE OF RESPONSE ACTION WITHIN SITE STRATEGY ......... Q
 V.   SITE CHARACTERISTICS ....                       «^m«ai ....... y

                                                       '    •
                                             R£SOURCE u^s         14
                                                ......................
      REMEDIATION OBJECTIVES                                      17
 IX.   DESCRIPTION OF ALTERNATIVES  .   .................................  o
 X.    COMPARATIVE ANALYSIS OF ALTERNATIVES    ...................... 99
 XI.   SELECTED REMEDY .......               ..........................  *
 Xn.   STATUTORY DETERMINATIONS ..        ....................... ...... -Z
 XHI.  DOCUMENTATION OF SIGNIFICANT CHANGES FROiM PREFERRED ........ "
      ALTERNATIVE OF PROPOSED PLAN ...................... . _ .  . .      38


                               FIGURES
                                                                   o

                               TABLES
                            . ............. ............                27


                     RESPONSIVENESS SUMMARY

STAKEHOLDER ISSUES AND EPA RESPONSES                             -,0
TECHNICAL AND LEGAL ISSUES .............. '..'.'.'.'.'.'.'.'.'.'.'.'.'. ................ 42
                                                                  43
                                 Vll

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                                    ACRONYMS
 ARAR
 CSB
 CERCLA

 CFR
 COCs
 CVD
 DOE
 Ecology
 EIS
 EPA
 ERDF
 ETF
 IWTS
 MCO
 NCP
 NEPA
 NPL
 NRG
 O&M
 PCB
 RCRA
 RCW
 RDR/RAWP
 ROD
 SARA
 SNF
 Tri-Parties

 TRU
 TBC
TSCA
use
WAC
WIPP
 applicable or relevant and appropriate requirements
 canister storage building
 Comprehensive Environmental Response, Compensation, and Liability Act
 of 1980
 Code of Federal Regulations
 contaminants of concern
 cold vacuum drying
 U.S. Department of Energy
 Washington State Department of Ecology
 environmental impact statement
 U.S. Environmental Protection Agency
 Environmental Restoration Disposal Facility
 Effluent Treatment Facility
 Integrated Water Treatment System
 Multi-Canister Overpack
 National Oil and Hazardous Substances Pollution Contingency Plan
 National Environmental Policy Act
 national priority list
 Nuclear Regulatory Commission
 operations and maintenance
 polychlorinated biphenyl
 Resource Conservation and Recovery Act of 1976
 Revised Code of Washington
 Remedial Design Report/Remedial Action Work Plan
 record of decision
 Superfund Amendments and Reauthorization Act of 1986
 Spent Nuclear Fuel
 U.S. Department of Energy, Richland Operations Office; U.S. Environmental
 Protection Agency; and Washington State Department of Ecology
 transuranic
 to be considered
 Toxics Substances Control Act of 1976
United States Code
Washington Administrative Code
Waste Isolation Pilot Plant
                                       vm

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                                 DECISION SUMMARY
                    I. SITE NAME, LOCATION, AND DESCRIPTION

 This Record of Decision (ROD) addresses the contents of the K Basins, which are located at the
 Hanford Site. The Hanford Site is a 586 square mile Federal facility operated by the U.S.
 Department of Energy (DOE) near Richland, Washington (figure 2, Hanford Site map).  The
 region includes the incorporated cities of Richland, Pasco, and Kennewick (Tri-Cities) and
 surrounding communities in Benton, Franklin, and Grant counties. Four areas within the
 Hanford Site were listed on the National Priorities List (NPL) in November 1989 under the
 Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA)
 as amended by the Superfund Amendments and Reauthorization Act of 1986 (SARA). The four
 NPL Sites are the 100 Area, 200 Area, 300 Area, and 1100 Area.

 The 100 Area, which encompasses approximately 68 km2 (26 mi2) bordering the south shore of
 the Columbia River, is the site of nine retired plutonium production reactors. Two of the reactors
 (K-East and K-West) reside in the 100-KR-2 Operable Unit in the 100-K Area. Adjacent to each
 of these reactors is a spent nuclear fuel (SNF) storage basin (figure 2, 100-KR-2  Operable Unit
 with K Basins). The contents of those basins are addressed in this ROD.

 The K Basins are currently being used to store irradiated (spent) nuclear fuel from past
 operations. The basins are located inside the reactor building and hold 1.3 million gallons of
 water each. The water provides a radiation shield, as well as a thermal sink for heat generated by
 the stored SNF. The SNF consists of metallic uranium clad in either a Zircaloy or aluminum
jacket. The cladding on some of the SNF has been damaged, allowing contact between the
 irradiated uranium and the basin water.  Corrosion of the damaged fuel results in transfer of
 radionuclides to the basin water and produces contaminated sludge. The SNF, sludge, water, and
 debris in the basins are described further in Section V, Site Characteristics.

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                 n. SITE HISTORY AND ENFORCEMENT ACTIVITIES

  The Hanford Site was established during World War E as part of the "Manhattan Project" to
  produce plutonium for nuclear weapons. Hanford Site operations began in 1943 and continued
  until 1990 producing nuclear materials for the nation's defense. Past Hanford Site operations
  resulted in the planned and unplanned release to the environment of large quantities of
  radioactive and hazardous substances. More than 2,000 waste sites have resulted.

  In 1988, the Hanford Site was scored using the EPA's Hazard Ranking System.  As a result of the
  scoring, four areas within the Hanford Site were added to the NPL in November 1989 (the 100
  Area, the 200 Area, the 300 Area, and the 1100 Area).  Each of these areas was further divided
  into operable units (a grouping of individual waste units based primarily on geographic area and
  common waste sources). The 100 Area NPL site consists of 17 source operable units
  (comprising contaminated sources such as soils, structures, debris, and burial grounds) and five
  groundwater operable units. The K Basins are contained in the 100-KR-2 Operable Unit.

 In anticipation of the NPL listing, DOE, the U.S. Environmental Protection Agency (EPA), and
 the Washington State Department of Ecology (collectively, the Tri-Parties) entered* into a Federal
 Facility Agreement and Consent Order in May 1989 known as the Tri-Party Agreement. This
 agreement established a procedural framework and schedule for developing, implementing, and
 monitoring remedial response actions at the Hanford Site. The agreement also addresses
 Resource Conservation and Recovery Act (RCRA) compliance and permitting.

 The K-East and K-West Reactors operated from 1955 until 1970 and 1971, respectively. Most of
 the SNF in the K Basins was removed at the tune of the shutdown. The K Basins were reused to
 store SNF from the N Reactor beginning in 1975 for K East and 1981 for K West and continues
 today. The K Basins presently contain SNF, contaminated sludge, water, and debris. Past leaks
 from the basins have contaminated the underlying soil and groundwater. The basins' integrity
 continues to degrade with age as does the condition of the SNF which increases risk to the
 environment and poses potential safety issues.

 In the early 1990s, the DOE determined that action was necessary to mitigate further releases
 from the basins and SNF degradation. The DOE used the National Environmental Policy Act of
 1969 (NEPA) process to evaluate alternatives for action and issued an environmental impact
 statement (EIS) in 1995. The alternatives focused on managing the SNF, with secondary
 discussions of the sludge, water, and debris.  The alternative selected in the resulting 1996 NEPA
 ROD was to remove the SNF from the basins, stabilize it at a facility located in the 100-K. Area,
 and place it hi interim storage in the 200 Area in central Hanford.  The selected alternative also
 included removal and pretreatment of the water and transfer to an existing treatment facility in
 the.2.°.° '
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 authority. CERCLA provided EPA the vehicle for a legally enforceable schedule under the Tri-
 Party Agreement and also allows for cost-effective disposal of waste to the Environmental
 Restoration Disposal Facility (ERDF) that can only accept Hanford Site CERCLA waste.

 The purpose of the K Basins CERCLA interim remedial action is to mitigate the potential to
 release hazardous substances from the K Basins, Within this scope is removal of the SNF,
 sludge, water, and debris from the basins, pretreatment of the water, and basin deactivation (see
 figure 1). Other activities covered in the K Basins EIS and ROD, namely the stabilization and
 interim storage of the SNF, are not addressed by this interim remedial action. Stabilization and
 interim storage of the SNF continue to be conducted under the authority of the Atomic Energy
Act of 1954 as analyzed via the NEPA process.  The SNF Cold Vaccum Drying (CVD) and
 Canister Storage Building (CSB) facilities are being constructed to be equivalent to current
Nuclear Regulatory Commission (NRC) standards and operating procedures being developed
 such that SNF management beyond the scope of this CERCLA action does not present an
endangerment to public health, welfare, or the environment. The NEPA analysis of
environmental impacts  associated with removing SNF, sludge, water, and debris from the K
Basins and pretreating the water were used hi the CERCLA process. Sludge treatment processes
were not analyzed in the NEPA process, but were analyzed in the CERCLA feasibility study.

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     Figure 1. Paths for Management of Waste Stored in the K Basins.
  Permanent storage
     in National
Geological Repository
   Fuel storage In
      200 Area
  Dispose treated
   water at State
 Approved Liquid
Disposal Site in 200
       Area
 Fuel drying facility
     in 100 Area
                                                        Dispose at ERDF
                                                       Transfer to ERDF
 Treatment at ETF
                           Transfer to effluent
                           treatment facility in
                                200 Area
                               Treat and
                              package for
                           disposal at ERDF
Transfer to fuel
 drying facility
                              K Basins
                                                              Separate
                                                           non-transuranic
                                                              sludges
                            Transfer sludge
                          to storage facility in
                               200 Area
                         Storage & treatment at
                       RCRA permitted facility in
                       200 Area, along with other
                       Hanford transuranic waste
                           Dispose at Waste
                            Isolation Pilot
                                Plant
                                  4

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                        Figure 2. Hanford Site.
Washington
   State
                              State Highway 24
                      100Dand
                      DR Areas
            100 K-Wat and
            K-East Arams
Plutonium
Finishing
  Plant
                                                         Washington
                                                         Public Power
                                                        Supply Svstem
                                                      n
                                                   400 Area
                                                    (FFTF)
                                   Arid Lands
                                    Ecology
                                    Preserve
Hanford
Site
Boundary
                                                                          3000
                                                                          Area

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Figure 3.100-K Area with K Basins.

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                         m. COMMUNITY PARTICIPATION

 The K Basins project has had very high visibility for half a decade with frequent dialogue with
 involved community stakeholders and Native American Tribes. Included in that community
 participation were four notable formal public comment opportunities: as part of DOE's NEPA
 efforts in 1995, around July 1997 and again hi October 1998 on cleanup milestones for the Tri-
 Party Agreement, and then for the Proposed Plan leading to this ROD.

 The Tri-Parties developed a Community Relations Plan in April 1990 as part of the overall
 Hanford Site restoration. The Plan was designed to promote public awareness of the
 investigations and public involvement hi the decision-making process. The community relations
 plan was updated hi 1993 and again hi 1996 to enhance public involvement.

 A fact sheet supporting the Feasibility Study and Proposed Plan public comment was mailed to
 over 1200 people who have identified themselves as "highly interested" in the Hanford cleanup.
 This mailing list included the members of the Hanford Advisory Board (a citizen / stakeholder
 site-specific advisory board), Native American Tribes who have reserved treaty rights to
 Hanford-related resources, and Natural Resource Trustees.  A calendar of Hanford events that
 listed this public comment period, public meeting, and point of contact was mailed to over 3700
 people who have identified themselves as "interested" in the Hanford cleanup. The Proposed
 Plan and Focused Feasibility Study Document were available to the public hi both the
 Administrative Record and the Information Repositories maintained at the locations listed below.
 The documents were posted on the Internet with the Internet address advertised in the fact sheet
 and newspaper ad. The newspaper ad was run twice in the Tri-City Herald newspaper, on the
 Sunday before public comment started and again on the Sunday before the public meeting.
These documents underwent a 45-day public comment period from May 15,  1999 to June 28,
 1999 and a public meeting was held hi Richland, Washington on June 10, 1999.  Focus sheets
and Proposed Plans were distributed upon request.
      ADMINISTRATIVE RECORD

             U.S. Department of Energy
             Richland Field Office
             Administrative Record Center
             740 Stevens Center
             Richland, Washington  99352

      INFORMATION REPOSITORIES

             Universities of Washington
             Suzzallo Library
             Government Publications Room
             Mail Stop FM-25
             Seattle, Washington 98195

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              Gonzaga University
              Foley Center
              E. 502 Boone
              Spokane, Washington  99258

              Portland State University
              Branford Price Millar Library
              Science and Engineering Floor
              SW Harrison and Park
              P.O. Box 1151
              Portland, Oregon 97207

              DOE Richland Public Reading Room
              Washington State University, Tri-Cities
              100 Sprout Road, Room 130
              Richland, Washington  99352

Six individuals provided public comments.  These comments and EPA responses are included in
the Responsiveness Summary, which is attached to this ROD. This decision document presents
the selected interim remedial action for the fuel, sludge, water, debris, and deactivation of the
basins in order to mitigate the potential to release hazardous substances from the basins.  The
selected interim remedy is chosen in accordance with CERCLA, as amended by SARA, and to
the extent practicable, the National Contingency Plan (NCP). The decision for these operable
units is based on the Administrative Record.

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       IV. SCOPE AND ROLE OF RESPONSE ACTION WITHIN SITE STRATEGY

  The goal of the CERCLA interim remedial-action is to mitigate the potential to release hazardous
  substances from the K Basins. This will be achieved by removing SNF, sludge, water, and
  debris, and conducting contaminant removal during deactivation of the basins. The scope of the
  K Basins CERCLA interim remedial action consists of the following:
   *
        Remove SNF, sludge, debris, and water from the basins.
   *    Transfer SNF to the 100-K Area Cold Vacuum Drying facility.
   *    Transfer sludge to the 200 Area sludge treatment and storage facility or the ERDF.
   *    Treat non-TRU sludge to meet ERDF waste acceptance criteria and dispose at ERDF.
   *    Treat water with the Integrated Water Treatment System (IWTS) and transfer it to the
        Effluent Treatment Facility(ETF).
   *    Treat debris, and transfer to disposal or storage facilities in the 200 Area.
   *    Deactivate the basins. Removed material will be managed as debris.

 The scope of this CERCLA interim remedial action does not include the following:

   *     Stabilization, interim storage, or final disposition of the SNF
   *     Treatment of sludge for interim storage at the 200 Area sludge treatment and storage
        facility                                                                 °
        Interim storage or final disposition of the sludge, water, or debris (except for any disposal
        at the ERDF which is part of this CERCLA interim remedial action)
        Final decontamination and decommissioning of the basin structures or remediation of
        underlying soil and groundwater.

 Stabilization and interim storage of the SNF continue to be conducted under the authority of the
 Atomic Energy Act of 1954 as analyzed by DOE via the NEPA process. Treatment, storage or
 disposal facilities  in the 200 Area for sludge, water, or debris are all regulated by existing permits
 or RODs from EPA and/or the State of Washington. Operation of those facilities are beyond the
 scope, but will receive waste from this interim remedial action.

 The contents of the K Basins must be removed before it will be practical to remediate the basin
 structures or underlying soil.  The basin structure'and underlying soil are included as waste sites
 100-K-42 (K-East Basin) and 100-K-43 (K-West Basin) in the 100 Area Remaining Sites Interim
 Action ROD signed July 1999.  The selected remedy for these waste sites is excavation,
 treatment as necessary, and disposal at the ERDF according to cleanup levels set forth in the
 Remaining Sites ROD.  The cleanup levels in the Remaining Sites ROD were established to
 support unrestricted human surface use and protection of the groundwater and Columbia River.
 Remediation of contamination in groundwater is addressed through 100-KR-4 Operable Unit
 decision documents: For example, the April 1996 1OO-KR-4 interim remedial action ROD    «
 addresses a chromium plume originating from liquid discharge to the nearby 116-K-2 liquid
 waste trench.

 Generally, the Hanford 100 Area is being cleaned up to Washington State's Model Toxics
Control Act standards for non-radionuclides for human residential exposure. Radionuclide
contaminants  are being cleaned up to  15 mrem/year above background radiation dose also based

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on a residential exposure.  Waste is being removed from the 100 Area, which is adjacent to the
Columbia River, to the 200 Area in central Hanford. The 200 Area is intended for long-term
storage and disposal.  Some of the waste sent to the 200 Area, such as the SNF and transuranic
(TRU) sludge is ultimately expected to be sent off-site. This CERCLA interim remedial action is
consistent with the waste management approach used in other CERCLA decision documents.

This is an interim remedial action ROD. Therefore review of this operable unit and the remedy
will be ongoing as the Tri-Parties continue to develop and implement final remedial alternatives
for the operable units and the 100 Area NPL site. Because this remedy will result in hazardous
substances remaining on-site above health-based levels, EPA will conduct a review within five
years after commencement of remedial action to ensure that the remedy continues to provide
adequate protection of human health and the environment.
                                        10

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                              V. SITE CHARACTERISTICS

  The Hanford Site occupies 586 square miles within the semiarid Pasco Basin of the Columbia
  Plateau in southeastern Washington. The Columbia River flows through the northern part of
  Hanford and, turning south, forms the eastern boundary of the site.  The river is bounded by wide
  expanses of uplands. These uplands contained abundant natural resources, including native
  plants, wildlife, and geologic resources.  In addition, the Pasco Basin is where the Snake River
  and the Yakima River join the Columbia River, providing a wealth of riparian areas as well as an
  excellent means of transportation throughout the semiarid inland northwest.  These rivers
  contained enormous fisheries.

  The entry of the U.S. into World War H and the decision to develop an atomic bomb led to a
  search for a suitable place to locate plutonium production and purification facilities. The U.S.
  Army Corps of Engineers selected the site near the towns of White Bluffs and Hanford because
  of the remote location, good climate, and, most important, the abundant supply of hydroelectric
 power and clean water from the Columbia River. The selection was made in early 1943.
 Plutonium for nuclear weapons were produced in nuclear  reactors built along the Columbia River
 at the Hanford Site.  Two of the nine total reactors are  the K-East and K-West reactors which
 operated from 1955 to 1970 and 1971, respectively. Adjacent to each of these reactors are SNF
 storage basins (i.e. the K-East and K-West Basins).

 The K-East and K-West Basins are currently being used to store irradiated nuclear fuel elements
 from past operations. The basins are located inside the reactor building and hold 1.3 million
 gallons of water in each basin. The water provides a radiation shield, as well as a thermal sink
 for heat generated by the stored SNF. The SNF consists of uranium clad in a metallic jacket.
 The cladding on some of the SNF has been damaged, allowing contact between the irradiated
 uranium and the basin water.  Corrosion of the damaged fuel results in transfer of radionuclides
 to the basin water and produces contaminated sludge.  The materials and wastes that will be
 addressed by the interim remedial action consist of the SNF, sludge, water, and debris that are
 further described in Sections 5.1 through 5.4

 5.1 Spent Nuclear Fuel

 Approximately 2,100 metric tons (2,300 tons) of SNF are stored in the K-East and K-West
 Basins. Most of the fuel is from the past operation of the N Reactor.  The SNF consists primarily
 of metallic uranium, but also includes plutonium and radioactive fission and activation products.
 The fuel is encased in either a Zircaloy or aluminum cladding.

 The K-East Basin contains about 1,150 metric tons (1,260  tons) of SNF, stored underwater in
 3,673 open-top canisters. Most of this SNF has been stored for varying lengths  of time ranging
 from 9 to 25 years. Much of the SNF stored in the K-East  Basin is damaged, and it has been
 estimated that about one percent of the original-mass of the fuel has corroded because of cracks
 and breaks in the cladding which has contributed to  the volume of radioactive sludge in that
 basin.

 The remainder of SNF, approximately 953 metric tons (1,050 tons), is stored underwater in the
K-West Basin in 3,817 closed canisters. Because the SNF  was placed in closed  containers before


                                          11

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  storage, corrosion products were retained within the canisters and the volume of sludge
  accumulated on the floor of the K-West Basin is much smaller than in the K-East Basin. As
  discussed in Section VI, removal of the SNF from the K Basins is included within the scope of
  this interim remedial action, although stabilization, interim storage and final disposition are not.

  5.2 Contaminated Sludge

  The K Basins contain a total of about 1800 cubic feet of highly-radioactive sludge that resides on
  the basin floors, in the basin pits, and in the SNF storage canisters. Sludge will also be generated
  as the SNF is washed prior to removing it from the basins. The composition of the sludge is
  complex and varies depending on the location and the basin.  Sludge consists of SNF corrosion
 products (including metallic uranium, uranium hydrides and oxides, plutonium, fission and
 activation products, and aluminum and  zirconium compounds from the cladding), metal oxides
 from corrosion of basin equipment including aluminum SNF canisters, ion exchange media from
 the water treatment system, concrete grit from the basin walls, sand, and dirt.

 Sludge components are not uniformly distributed throughout the basin sludge. Large quantities
 of SNF corrosion products in the floor and pit sludge are a result of the open tops, and in some
 cases open-screened bottoms, of the SNF storage canisters in the K-East Basin. Sludge in the K-
 East Basin canisters themselves consists primarily of fuel corrosion products.

 There is very little sludge on the floor of the K-West Basin, and what there is appears to consist
 primarily of dust and sediment. The floor sludge is not expected to contain significant amounts
 of fuel corrosion products because the canisters in the K-West Basin have closed tops and
 bottoms, but there are still low levels of radioactivity in the floor sludge. Only one of the areas
 in the K-West Basin (the North Loadout Pit) contains a significant amount of sludge and this is
 likely to consist  of a mix of sand and fuel corrosion products. Because the canisters in the K-
 West Basin are completely closed, any sludge in them is expected to derive almost exclusively
 from SNF and consist of fuel corrosion products.

 Based on sludge characterization data, the sludge designates as a TRU waste (a radioactive waste
 that contains greater than 100 nanocuries per gram of transuranic radionuclides with a half life
 greater than 20 years) under the Atomic Energy Act. It might also be a dangerous waste under the
 Resource Conservation and Recovery Act (RCRA) and the state Hazardous Waste Management
Act based on total concentrations of cadmium, chromium, and lead. Finally, the sludge is
 regulated as a PCS (polychlorinated biphenyl) remediation waste under the Toxics Substances
 Control Act due to small amounts of incidental contamination with PCBs.

5.2.1 Sludge Management Concerns

Concerns that were important in evaluating remedial alternatives for the sludge included the
following:

 *    The surface dose for an unshielded container of sludge is many times higher than the
      2pO-mrem/hr limit for contact-handled waste.  The contact dose associated with floor and
      pit sludge could be as high as 128,000 mrem/hr and the contact dose rate associated with
      canister and wash sludge could be as high as 1.75 million mrem/hr. Because of this, it is


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        anticipated that containers of sludge will need to be managed as a remote-handled waste
        unless special overpacking is provided.
        The high concentrations of fissile materials (uranium and plutonium) require careful
        evaluation of criticality control for all activities involving the sludge.
  *     Metal fines and metal hydrides in fee sludge (e.g., uranium, uranium hydride, and
        zirconium) are potentially pyrophoric, reactive, and capable of generating flammable gas.

 5.3 Contaminated Water

 Each basin contains approximately 1.3 million gallons of water that is used to shield and cool the
 SNF.  The water is currently maintained in a closed-loop system and is continually recycled from
 the basins, circulated through existing treatment systems, then returned to the basins.  This
 treatment is necessary to maintain adequate water quality (e.g., reduce cloudiness) and reduce
 concentrations of soluble radionuclides.  Based on current chemical characterization data, the
 water is not regulated as a dangerous waste or as a PCB remediation waste. As outlined in
 Section IV, the interim remedial action is limited to pretreatment of the water using the in-basin
 treatment system and transport to the ETF.

 5.4 Contaminated Debris

 Basin debris comprises a wide spectrum of materials.  These include approximately 7,500 fuel
 canisters, old basin equipment and piping, hand tools, fuel canister storage racks, construction
 materials from the basins, equipment used for basin clean out, components of the basin water
 pretreatment system, and waste generated during deactivation of the basins such as contaminated
 equipment and structural materials.

 Most of the debris is expected to designate as low-level radioactive waste under the Atomic
 Energy Act. Some  of the debris may designate as mixed (radioactive and dangerous) waste, TRU
 waste, or mixed TRU waste, depending on the chemical composition of the debris itself and
residual sludge attached to the debris. The debris is also regulated as a PCB remediation waste
where it has contacted sludge.
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       VI. CURRENT AND POTENTIAL FUTURE SITE AND RESOURCE USES

 Current land use in the 100 Area of Hanford includes facilities support, environmental cleanup,
 and waste management. Facilities support activities include operations such as water treatment
 and maintenance of the reactor buildings. Environmental cleanup activities include excavation
 of contaminated soil, groundwater extraction and treatment, and building decontamination and
 decommissionmg. Waste management activities include surveillance and maintenance of former
 disposal waste sites now know as "past-practice sites" located throughout the 100 Area as well as
 management of wastes generated during other 100 Area activities. There are also substantial
 tracts of undeveloped land located throughout the 100 Area that comprise approximately 90
 percent of the land area within the 100 Area. These areas have been disturbed very little and
 contain minimal infrastructure.

 Future land use of the 100 Area has not been determined. 100 Area waste sites are being
 remediated so as not to preclude any future surface use.  Groundwater is currently used for
 monitoring contaminant plumes and is subject of a number of CERCLA cleanup actions. The
 groundwater meets state technical standards for a potential drinking water source (pumpability
 and total dissolved solids), but because of contamination from Hanford Site operations, it would
not be useable for any purpose in its present condition.  Future use of the groundwater has not
been determined and depends in large part on cleanup capabilities and future land use.
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                             VII.  SUMMARY OF SITE RISKS

  The hazardous substances addressed by this interim remedial action are derived from the SNF
  and include the SNF, sludge, debris, and water present in the K-East and K-West Basins and
  contamination removed as part of deactivation. These items were described in Section V  Basin
  leaks have contaminated underlying soil and groundwater which contributes to the risk from the
  basins and hence the need for this interim remedial action. This interim remedial action
  addresses the contents of the basins to mitigate the potential for future releases.  The two basin
  structures and underlying contaminated soil have been addressed in the July 1999 Remaining
  Sites Interim Remedial Action ROD, and groundwater is being addressed in 100-KR-4 Operable
  Unit decision documents as described in Section IV.

  The contaminants of concern in the K Basins that drive the risk evaluation are primarilv
  radionuchdes. The basins contain about 55,000,000 curies of radioactivity. Concentrations of
  radionuchdes in the K Basins sludge and SNF are such that unshielded exposure would result in
  a significant radiation dose.  Potential risks to human health and the environment associated with
  current conditions at  the K Basins include the following:

  Potential for releases.  The basins have leaked millions of gallons of contaminated water to the
  groundwater that discharges to the nearby Columbia River. Monitoring wells between the basins
  and the Columbia River have documented the radioactive plume. Tritium has been measured
  over a hundred times  the drinking water standard of 20,000 pCi/L.  Strontium-90 has been
 measured over a thousand times the drinking water standard of 8 pCi/L. Any substantial release
 ol water or sludge from the basins causes further degradation of the groundwater. Deficiencies at
 both basins continue to present a potential for future leaks.

 Fuel degradation.  The SNF was not designed for long-term storage in water.  However, some
 of the SNF has been stored underwater in the basins for more than 20 years. In the K-East Basin
 damaged fuel cladding surrounding the metallic uranium fuel elements has  allowed water to
 corrode the fuel. The  corrosion further damages the fuel, releasing radioactive material to the
 water and contributing to the buildup of a thick layer of sludge on the basin floor.

 Basin Design  and seismic adequacy. As the basins continue to age there is a potential for
 further loss of structural integrity and further releases from the basins to the environment. The
 K Basins were designed to consensus codes and standards of the early 1950s. The K Basins have
 currently exceeded their 20-year design life by more than 20 years. Upgrades to equipment and
 systems are required to ensure occupational safety and environmental protection  The basins do
 not provide confinement of radioactive materials released to the air, nor liquid released in the
 event of a leak. In addition, the basins were not designed to modern seismic criteria Basin
 failure during a seismic event could allow large volumes of water to leak to  the soil  Failure to
 maintain a sufficient amount of water to cool the SNF and sludge and provide shieldin* for
 workers would allow the SNF and sludge to dry and heat, resulting in an airborne release of
 radionuclides.

Location. The K Basins are located approximately 430 m (1,400 ft) from the Columbia River
The proximity of the basins to the river increases the likelihood that the river would become
contaminated as a result of a leak from the basins and migration to the soil and groundwater
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 Occupational exposure. The lack of confinement for the corroding fuel in the K-East Basin has
 resulted in higher than desired radiation exposure to workers during routine and non-routine
 activities. Dose reduction activities are underway at the basin. These activities are designed to
 improve overall occupational safety at the K Basins but are not expected to achieve current
 standards for occupational exposure for prolonged storage at the K Basins.

 Risk Summary A major natural event (e.g., seismic event) could release most or all of the basin
 water and potentially some of the basin sludge to the subsurface environment, where it could
 leach to groundwater and be transported to the Columbia River. The potential risk to the
 environment and human health combined with the continued occupational risk to workers
justifies this interim remedial action. The response action selected in this ROD is necessary to
protect the public health or welfare or the environment from actual or threatened releases of
hazardous substances from the K Basins into the environment.
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                         VIBL REMEDIATION OBJECTIVES

 The overall purpose of this interim remedial action is to mitigate the potential to release
 hazardous substances from the K Basins by removing the SNF, debris, sludge, and water from
 the K Basins, deactivate the basins, and transfer the SNF and waste to facilities that will manage
 them in a manner that protects human health and the environment. The scope of this interim
 remedial action does not include final disposition of the basin structures themselves or
 remediation of the underlying soil or groundwater. Disposition of the basins, contaminated soil
 and groundwater has been or will be addressed under other CERCLA actions as-described in  '
 Section IV. This interim remedial action only addresses the immediate risks associated with the
 contaminants in the basins. Enforceable Tri-Party Agreement milestones have been established
 to accomplish this interim remedial action in a safe and expeditious manner. Final cleanup levels
 appropriate to future use scenarios are beyond the scope of this interim remedial action  and have
been or will be set in other CERCLA decision documents.

The Remedial Action Objectives are as follows:

       Reduce the potential for future releases of hazardous substances from the K Basins to the
       environment.
             Remove hazardous substances from the K Basins near the Columbia River in a
             safe and timely manner.
             Provide for safe treatment, storage, and final disposal of the SNF, sludge water
             and debris removed from the K Basins.
             Prevent further deterioration of the SNF.
      Reduce occupational radiation exposure to workers at the basins.
*     Address the sludge management concerns identified in Section 5.2.1.
      Develop the most cost effective site-wide approach, consistent with the CERCLA nine
      criteria, for treatment, storage, and disposal of sludge.
      Treat, store, and/or dispose of sludge soon after removal.
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                       IX.  DESCRIPTION OF ALTERNATIVES

 The K Basin project had undergone aNEPA analysis of alternatives (see Section II) leading to a
 definitive decision for the SNF, water, debris, and deactivation. Therefore, the focus of the
 feasibility study was sludge treatment. Five remedial action alternatives were included in the
 focused feasibility study and proposed plan. Their names derive from the type of treatment of
 the sludge. Except for no action, all the alternatives are identical with respect to SNF, water,
 debris, and deactivation.

 The remedial alternatives for the sludge consist of the following:

       Alternative 1: No Action
       Alternative 2: Chemical Treatment
       Alternative 3: Physical Treatment
       Alternative 4: Thermal Treatment
       Alternative 5: Solidification

 9.1 Overview of Alternatives Development for Sludge

 The sludge treatment alternatives were developed with the intent of treating the K Basins sludge
 as a unique waste stream before combining it with other Hanford waste for final treatment and
 disposal. The feasibility study showed there were implementability issues and high costs (see
 table 9-1) for all of the treatment alternatives.  Treatment of K Basins sludge as a unique waste
 form would not take full advantage of the economies of scale possible by combining with other
 large capacity waste treatment processes under development at Hanford. Therefore, this ROD is
 not selecting any of the sludge treatment alternatives for large-scale implementation for K Basins
 sludge.

 Just prior to public comment, an additional alternative analysis supported doing the minimal
 treatment of sludge necessary  to support storage in existing permitted regulated facilities in the
 200 Area. The K Basins sludge would then be treated and disposed as part of the much larger
 TRU waste stream at Hanford that is addressed under milestone M-91 in the Tri-Party
 Agreement. Most of the sludge is not expected to need'treatment prior to storage in the 200
 Area. Any treatment that would be needed prior to storage would be done as a permitted action
 at the storage facility.

 A small portion of the sludge that is non-TRU may be isolated from the rest of the sludge and
 undergo treatment by one of more of these alternatives to meet ERDF waste acceptance criteria.
The original sludge treatment alternatives are described briefly in the following section as they
may be applied in a small scale to a small portion of the sludge if needed to meet the waste
 acceptance criteria of ERDF.

9.1.1 Alternative 1: No Action

The No Action Alternative represents a situation where there would be continued storage of the
SNF, sludge, debris, and water in the K Basins for up to 40 years with no .modifications except
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 for routine maintenance, monitoring, and ongoing safety upgrades.  There would be no major
 upgrades to significantly enhance storage capabilities.

 9.1.2 Alternative 2: Chemical Treatment

 Acid would be used to dissolve the sludge to reduce the size of sludge particles (a part of
 criticality control) and make metals less reactive. Iron or depleted uranium that absorbs
 radioactive energy would be added to the acid solution to prevent criticality. Chemicals would
 be added to neutralize and adjust the solution. Treated sludge would be stored in an existing 200
 Area storage facility.

 9.1.3 Alternative 3: Physical Treatment

 Two types of physical treatment were combined for this alternative; grinding/milling and
 physical separation based on particle size.  A high-energy mill would be used to grind the sludge
 to reduce the size of sludge particles (a part of criticality control) and make metals less reactive.
 Large particles would be separated and recycled to the grinder. Iron or depleted uranium would
 be added to the solution after grinding to prevent criticality. Chemicals would be added to adjust
 the solution.  Treated sludge would be stored hi the 200 Area sludge storage facility.

 9.1.4 Alternative 4: Thermal Treatment

 Two thermal treatment options evaluated were vitrification and calcination.  The sludge would be
 separated into three streams  as it was removed from the basins: small particles, large particles,
 and organic resin beads. The small particles would be vitrified or calcined.  The large particle's
 would be dissolved hi acid, then vitrified or calcined.  The glass would be stored in the 200 Area
 of the Hanford Site and eventually shipped offsite to the national geologic repository. Calcined
 waste would be packaged and stored hi the 200 Area of the Hanford Site and eventually shipped
 offsite to the Waste Isolation Pilot Plant (WIPP). The thermal process would be designed so that
 the treated waste would meet the requirements for offsite disposal at a permitted facility.
 (Interim storage and disposal of the treated sludge are not part of this interim remedial action.)
 During sludge treatment, insoluble solids (such as zirconium) would be separated  from the
 sludge. The organic resin beads and insoluble solids would contain radionuclides and some of
 the PCBs. They would be treated as appropriate and disposed at the ERDF or at the Waste
 Isolation Pilot Plant in New Mexico.

 9.1.5 Alternative 5: Solidification

 The sludge would be separated into three streams as it is removed from the basins: organic resin
beads, small particles, and large particles. The sludge containing small particles would be
oxidized in hot water and the sludge containing large particles would be oxidized in small
 furnaces. The organic resin beads and oxidized sludge would be combined arid solidified using
materials such as Portland cement. The solidification process would be  designed to meet final*5
disposal requirements.

9.2 COMMON ELEMENTS
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  This section describes management of the SNF, water, and debris, and deactivation that is the
  same hi each of the action alternatives. Note that sludge management, which was different
  among the alternatives, was addressed in section 9.1.

  9.2.1 Spent Nuclear Fuel Management

  SNF will be removed from the basins, dried, and placed into dry storage.  Drying will be done at
  the CVD facility in the 100-K Area, and dry storage will be at the CSB in the 200 Area. Drying
  at the CVD facility and interim storage at the CSB are not part of this CERCLA interim remedial
  action.  The cold vacuum drying process and interim storage continue to be authorized under the
 Atomic Energy Act as evaluated under NEPA.  The specific activities conducted under the
  authority of this CERCLA interim remedial action are as follows:

   *     The SNF will be agitated to loosen and remove sludge and corrosion product; the sludge
        and corrosion product will remain in the basin to be consolidated with other sludge.'
   *     The SNF will be placed into fuel baskets, and the fuel baskets will be placed inside
        multi-canister overpacks (MCOs).
   *     The MCOs will be closed and transferred to the CVD for drying.  The CVD has  been
        constructed in the 100-K Area near the K Basins.
   *     Liquid drained from the MCOs at the CVD and during further processing will be returned
        to the K Basins for recycling, or transferred to the ETF.

 The SNF retrieval, washing, and packaging activities at the basins could potentially generate
 emissions such as  airborne paniculate. These activities will be conducted under water to control
 the generation of airborne particulate.

 The CVD is an appropriate facility for drying the SNF. The CVD is being designed and
 constructed to achieve nuclear safety equivalence comparable to Nuclear Regulatory
 Commission-licensed facilities. The use of standards consistent with Nuclear Regulatory
 Commission requirements provides a high level of safety and environmental protection.

 9.2.2 Water Management

 The K Basins together contain about 9.8 million L (2.6 million gal) of contaminated water.
 Under all the action alternatives the water will be treated in the basins with the IWTS, removed
 and transferred to the ETF in the 200 Area for further treatment, then disposed at the '
 State-Approved Land Disposal Site in the 200-Area. The activities that are part of this CERCLA
 interim remedial action are in-basin treatment, removal, and transfer to the 200 Area. Treatment
 at ETF and disposal at the State-Approved Land Disposal  Site are not part of this CERCLA
 interim remedial action.

 9.2.3 Debris Management

Debris is defined as any solid waste resulting from this CERCLA interim remedial action,
 excluding SNF, sludge, and wastewater. Debris includes items located both above and below the
water m the basins, wastes generated from operation of the water and sludge treatment systems,
and wastes generated during basin deactivation. Debris may also be generated during


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  deactivation of sludge treatment facility(ies) or equipment done as part of this CERCLA interim
  remedial action.
  Under all the action alternatives the debris will be removed from the K Basins. Debris will be
  treated as necessary to meet the waste acceptance criteria for disposal at ERDF. If debris cannot
  be treated to ERDF waste acceptance criteria, then the debris will be transferred to an existin^
  permitted waste management facility appropriate for the designation. When the debris is   °
  received at the storage or disposal facility, further waste management is beyond the scope of this
  interim remedial action.

  9.2.4 Basin Deactivation

 Deactivation will remove additional hazardous materials and place the basins into a condition
 such that they can be maintained safely with minimal surveillance and maintenance until
 remediation of the basin structure and releases to the underlying soil are performed  End point
 £f 6IS™ mf tlVatl°n WiU be mcluded * ** Remedial Design Report / Remedial Action Work
 Plan (RDR/RAWP).
1 	 Tab Ie 9-1. Alternatives Cost From Feasibility Studv

No Action
Chemical Treatment
Physical Treatment
Thermal Treatment
Solidification
CERCLA(l)
Not Evaluated
$689 M
$689M
$689 M
$689 M
Sludge(2)
Not Evaluated
$1 16-126 M
$98 M
$81-122 M
$94 M
Total(3)
Not Evaluated
$805-8 15 M
$787 M
$770-811 M
$783 M
(3)
                     	— •• --** M*.M.**.^W u. wtivl_U.WULfc CU1U. LtlOL/Woai.
       Includes costs to design, construct, and operate a sludge treatment system; and to dispose
       of the treated sludge. Does not include contingency, escalation, transport to final disposal
       facility, project management, regulatory support, or decontamination/decommissioning
       The feasibility study included sludge treatment as a CERCLA activity.  In this ROD the
       selected remedy does not include sludge treatment for interim storage, but does include
       sludge treatment for ERDF disposal.
Not Evaluated.       Costs for the No Action alternative were not evaluated in the Focused
                    Feasibility Study because the No Action alternative did not satisfy
                    threshold criteria.
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                  X. COMPARATIVE ANALYSIS OF ALTERNATIVES

 10.1   Overall Protection of Human Health and the Environment

 The No Action Alternative would fail to protect human health and the environment. The
 remaining alternatives would all provide overall protection of human health and the environment
 by removing hazardous substances from the K Basins and transferring them to facilities that are
 more protective, thereby reducing the potential for further degradation of the SNF and future
 releases from the basins.

 10.2   Compliance With Applicable or Relevant and Appropriate Requirements

 The No Action Alternative would not invoke new applicable or relevant appropriate
 requirements (ARARs) because no action would be taken; however, surveillance and
 maintenance activities at the K Basins would still be subject to currently applicable requirements
 under the No Action Alternative. The remaining alternatives would all meet ARARs.

 10.3   Long-Term Effectiveness and Permanence

 The No Action Alternative would not be effective or permanent because it would not address the
 risks at the K Basins. The remaining treatment alternatives would be equally capable of
 providing a high level of long-term effectiveness and permanence. The contaminants associated
 with the SNF, sludge, water, and debris would be removed from the K Basins  and placed at more
 environmentally protective facilities. The basin water would be removed, thus eliminating the
 primary driving force for contaminant migration.  After deactivation, the basins would be left in
 a condition where they would present minimal threat to the environment.  Final remediation of
 the basins will be undertaken as part of a later CERCLA action.

 None of the alternatives provide for immediate disposal of the bulk of the sludge, but in all cases
 the sludge would be transferred to facilities that are designed to provide safe interim storage and
 minimize the potential of an environmental release. The Thermal Treatment (Vitrification)  and
 Solidification Alternatives might be somewhat more effective than the Chemical Treatment,
 Physical Treatment, and Thermal Treatment (Calcination) Alternatives because an immobilized
 waste form would result "from treatment. Interim storage of an immobilized waste form, versus a
 slurry or calcined particles, would reduce the risk of releases to the environment.

 10.4   Reduction of Toxicity, Mobility, or Volume Through Treatment

The No Action Alternative would involve no treatment. The remaining alternatives would all
provide treatment of the K Basins water and sludge, and therefore, would be substantially better
than the No Action Alternative. The water treatment system would be the same under all of the
alternatives except No Action, so the alternatives would be equally effective in reducing the
toxicity associated with contaminated water. The alternatives vary significantly in how they
would perform against this criterion with respect to sludge treatment.
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  The Thermal Treatment (Vitrification) Alternative for sludge would perform best. Vitrification
  would reduce both toxicity (flammable gas generation and reactivity/pyrophoricity) and mobility
  significantly and reduce volume by 50 percent.

  The Physical Treatment, Thermal Treatment (Calcination), and Solidification Alternatives for
  sludge would all perform moderately well, but not as well as vitrification.  They would all reduce
  toxicity (flammable gas generation and reactivity/pyrophoricity) significantly, and physical
  treatment would reduce the potential for criticality. Solidification would perform much better
  than physical treatment or calcination in reducing mobility, but would perform worse in reducing
  volume (the volume would  increase by a factor of six).  Calcination would perform much better
  than physical treatment or solidification in reducing volume (volume would be reduced by about
  75 percent) but would not reduce mobility and would generate a dispersible waste form
  Physical treatment would not reduce mobility as part of this  CERCLA interim remedial action
  and the volume of sludge requiring interim storage would increase be a factor of five.

  Neither option under the Chemical Treatment Alternative for sludge would perform well against
  this criterion.  Chemical treatment would reduce toxicity (flammable gas generation and-
  reactivity/pyrophoricity) and the potential for a criticality. However, it would not reduce
  mobility as part of this CERCLA interim remedial action and both the interim and final volumes
  of waste produced would be several times greater than the original volume of sludge.

  10.5   Short-term Effectiveness

 With the exception of the No Action Alternative, the alternatives would perform equally well
 against the criterion of short-term effectiveness.

 Risk to public and the environment. All of the treatment alternatives have the potential to
 impact the public and environment through airborne releases  during removal and treatment
 activities, but none of the alternatives are expected to pose unacceptable risks. Control measures
 for the removal and transfer of SNF activities are well established. The potential for upset
 conditions may vary between alternatives depending on the type of sludge treatment, but the
 consequences of an upset condition would be similar because the contaminant inventory would
 be the same.

 Risk to workers. None of the alternatives would be expected to pose unacceptable short-term
 risks to site workers. The primary risk to workers is the risk associated with exposure to
 radiation; this risk would be similar for all alternatives.  Other risks would include chemical
 physical, and thermal hazards. These risks would be mitigated through engineering and
 administrative controls.

 Environmental impact. None of the alternatives would be expected to result in short-term
 impacts to the environment.

 Schedule. All of the alternatives except the No Action Alternative were developed to  meet the
 same schedule, specified in Milestone M-34 of the Tri-Party Agreement. Several key dates in
the milestone schedule are:
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   *    Start SNF removal from the K West Basin by November 2000.
   *    Start SNF removal from the K East Basin by November 2001.
   *    Complete SNF removal from the K East Basin by December 2003.
   *"    Complete K East Basin sludge removal by August 2005.
   *    Complete K East Basin water removal by October 2006.
   *    Complete M-34 activities (complete removal of SNF, sludge, debris, and water) from
        both basins by July 2007.

 10.6   Implementability

 The No Action Alternative performs poorly against this criterion because it would fail to comply
 with the K Basins EIS and NEPA ROD, Tri-Party Agreement schedules, and commitments made
 to the regulators, oversight agencies, stakeholders, and public.

 None of the treatment alternatives would perform well against this criterion in treating
 100 percent of the sludge volume because of technical and/or administrative uncertainties. The
 options under the Chemical Treatment Alternative would perform better than most. Chemical
 treatment is a mature technology that is well established in the nuclear industry and has been
 tested on K Basin sludge.

 All of the other treatment alternatives have significant disadvantages. Physical treatment would
 rely on the application of technologies that have not been used for similar waste types. There is
 also uncertainty about the process control, especially in grinding to very small particle sizes, and
 uncertainty about the time required to grind the largest particles and whether this would
 accommodate the Tri-Party Agreement schedule.  Significant development work would be
 required to determine if these issues could be resolved.

 Vitrification, calcination, and solidification are better than physical treatment in the near term
 because they are all mature technologies that are well established in the nuclear industry.
 However, they have not been tested using actual or simulated K Basins sludge and development
 work would be required.  There is an additional uncertainty as to whether calcined sludge, which
 would be a dispersible particulate waste, could be transported to the WIPP without further
 processing.

 There is an uncertainty associated with all of the treatment alternatives regarding whether a
 treatment system sized to treat the entire volume of sludge within the schedule for sludge
 removal identified in the Tri-Party Agreement could be located inside an existing facility. The
 need for a new facility would significantly affect cost and  schedule, as could resolution of other
 uncertainties.

 10.7   Cost

The alternatives do not vary significantly in overall cost of this CERCLA interim remedial
action, but they do vary significantly in the costs associated with sludge (see table 9-1). Costs
for the overall project are summarized in Table 10-1.  Costs in these tables are as of March 31,
 1999, rounded to the nearest S100,000 in future worth dollars. For expense dollars, the
escalation rate is 2.1% per year. For capital costs, 2.5% per year is used. Note that capital is a


                                          24

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  very small portion of the remaining cost for the project. Because of the difficulty in assessing and
  comparing costs for disposal at the WIPP versus at the national geologic repository, there is
  substantial uncertainty in the long-term costs.  The uncertainty in the cost estimates is plus 50%
  to minus 30%.

  10.8   State of Washington Acceptance

  The State of Washington concurs with the selected remedy which removes the contents of the K
  Basins and places it in protective facilities.

  10.9   Community Acceptance

  The community overwhelmingly supports the overall action of cleaning out the K Basins. The
  public comments related to sludge treatment presented in the Proposed Plan were mixed.  Very
  few public comments were received. Some comments supported  treating the sludge soon after
  removal from the basins.  Other comments supported the preferred alternative of storing the
  sludge pending future treatment with other Hanford waste.  A third opinion expressed in public
  comments was that there was insufficient information about what sludge treatment could look
  like to support public comment.

  10.10  Summary

 In summary, the No Action Alternative would fail to meet the requirements for this CERCLA
 interim remedial action. The other alternatives would all provide overall protection of human
 health and the environment, comply with ARARs, and be effective in the long term. All of the
 alternatives except No Action would achieve a substantial risk reduction by removing SNF
 sludge, water, and debris from the K Basins, transferring these materials to environmentally
 protective facilities, and deactivating the basins.  In all of the treatment alternatives the sludge
 would be treated to meet the acceptance criteria and all other applicable requirements at the
 interim storage and final disposal facilities. However, none of the treatment alternatives would
 perform well against all of the CERCLA criteria for the entire volume of sludge and range in
 sludge composition.

 All of the individual treatment alternatives are very expensive because they presume extensive
 treatment m a standalone facility dedicated to treatment of the K Basins sludge.  All of the
 individual treatment alternatives have significant issues related to the technical feasibility of
 using a particular technology or process for all of the sludge. Also EPA and DOE do not believe
 that any of the individual alternatives could be in place in time to treat the sludge as it is removed
 from the basins.  This problem could be addressed by placing the sludge  into interim storage with
 minimal treatment.

 None of the individual alternatives was an appropriate choice for the sludge, and every
 combination of retrieval/treatment options required interim storage. Therefore the preferred
 alternative in the proposed plan was to rely on interim storage with  minimal treatment as
necessary to support interim storage. The preferred alternative relies on future treatment of the
sludge to meet final disposal requirements. Since the design for sludge treatment after interim
                                          25

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storage was not available for public comment, the proposed plan committed to a future public
comment opportunity for final treatment for disposal.
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Table 10-1.  K Basins Project Cost"
Category
Project Management and Integration0
Basin Maintenance and Operation"1
Basin Facility Projects
SNF Retrieval
(Design/Modification/Construction)
SNF Cast Transportation System and MCO
Acquisition
SNF Retrieval (Operations)
Cold Vacuum Drying (CVD) Facility
(Design/Modification/Construction)
CVD Facility (Operations)
Canister Storage Facility (CSB)
(Design/Modification/Construction)
CSB (Operations)
Sludge Retrieval/Removal
(Design/Modification/Construction)
Sludge Retrieval/Removal (Operations)
Sludge Transport/Offloading
(Design/Modification/Construction)
Water Treatment
(Design/Modification/Construction)
Debris Removal
(Design/Modiflcation/Construction)
Debris Removal (Operations)
Site- Wide Spent Fuel Activities
Contingencyf
Reactivation
Sub Total, Common Elements8
Sludge Treatment*'
Design/Modification/Construction)
Sludge Treatment/Transport (Operations)*
Total'
CERCLA Cost
(SM)b
127.7
153.4
8.9
10.8
65.1
165.2
e.
e.
e.
e.
12.6
6.0
4.6
13.5
11.8
12.1
e.
97.1
133.5
822.3
36.6
3.7
862.6
Non-CERCLA
Cost (SM)
129.9
168.9
40.3
43.2
43.8
31.2
72.0
44.7
151.7
51.4
7.2
0.0
0.3
26.2
5.1
1.6
25.0
9.1
0.0
851.6
5.7
0.0
857.3
Total (SM)
257.6
322.3
49.2
54.0
109.0
196.3
72.0
44.7
151.7
51.4
19.8
6.0
4.9
39.7
16.9
13.7
25.0
106.2
133.5
1,673.7
42.3
3.7
1,719.7
              27

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                   Table 10-1.  K Basins Project Cost (continued, footnotes)

 a.     Costs as of March 31, 1999, rounded to the nearest $100,000 in future worth dollars. For
       expense dollars, the escalation rate is 2.1% per-year.  For capital costs, 2.5% per year is
       used. Note that capital is a very small portion of the remaining cost for the project.
 b.     Excludes costs incurred prior to this CERCLA ROD date assumed to be October 1, 1999,
       and costs outside the scope of the CERCLA interim remedial action.
 c.     Includes Project Fee (profit).
 d.     Includes maintenance and operation both before and after fuel removal.
 e.     Not in scope of CERCLA action.
 f.     Contingency only applies to fiscal year 1999 and beyond. Although  shown as a CERCLA
       cost, it will actually be distributed across both CERCLA and non-CERCLA costs.
g.     Subtotal reflects costs common to all of the treatment alternatives.
h.     Sludge treatment costs reflected in this cost table were planning estimates prior to the
       results of the focused feasibility study. The selected alternative in this ROD minimizes
       sludge costs as part of this CERCLA action.  This cost estimate is expected to be revised
       during remedial design.
i.      Does not include cost to dispose of the treated sludge, which is outside the scope of this
       project.
                                         28

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                                XI. SELECTED REMEDY

  The selected remedy shall satisfy ARARs established in Section 12.2 and meet the remedial
  action objectives in Section VUL Facilities used for treatment, storage, or disposal of waste
  generated as part of this interim remedial action must be approved by EPA via the RDR/RAWP
  or as otherwise authorized by EPA. An overview of the selected remedy is shown in figure 1.

  11.1   Selected Remedy for Spent Nuclear Fuel

  SNF will be removed from the K Basins hi accordance with the schedule in the Tri-Party
  Agreement. SNF will be transferred to the CVD facility. The specific activities required under
  this CERCLA interim remedial action are as follows:

        The SNF will be agitated to loosen and remove sludge and corrosion product; the sludge
        and corrosion product will be remediated as sludge (Section 11.2).
  *    The SNF will be placed into fuel baskets, and the fuel baskets will be placed inside
        MCOs.
  *    The MCOs will be closed and transferred to the CVD facility in the 100-K Area.
  *    K Basins water drained from the MCOs will be managed either by returning it to the
        K Basins or treatment, as necessary, and disposal as described for K Basins water.

 The SNF retrieval, washing, and packaging activities at the basins could potentially generate
 emissions such as airborne particulates. These activities will be conducted under water  to control
 the generation of airborne particulates. The SNF retrieval, washing, packaging, retrieval and
 transport shall be designed by DOE and included in the RDR/RAWP subject to EPA approval
 Treatment, storage, and disposal of the SNF after it reaches the CVD is outside the scope of this
 interim remedial action.  These activities are subject to requirements of applicable law, including
 the Atomic Energy Act.

 11.2   Selected Remedy for Sludge

 Sludge will be removed from the basins hi accordance with the schedule requirements of the Tri-
 Party Agreement. Most of the sludge will be transferred to a permitted storage and treatment
 facility in the 200 Area.  Any storage or treatment at the storage and treatment facility will be
 outside the scope of this interim remedial action. If it is determined during remedial design that
 a portion of the sludge could be treated to meet the ERDF waste acceptance criteria, and it is
 practicable and cost effective, then that treatment will be done as part of this interim remedial
 action. The treatment for ERDF disposal may take place at either the K Basins or the ERDF.
 The sludge treatment system as designed by DOE shall be included in an amendment to the
 RDR/RAWP subject to EPA approval.  Treatment shall optimize use of chemical, physical,
 thermal, and solidification treatment based on the ERDF waste acceptance criteria.

 11.3  Selected Remedy for Water

An  Integrated Water Treatment System (IWTS) shall be added to each of the basins hi
accordance with the schedule requirements of the Tri-Party Agreement. The IWTS will clear the
water so that reduced visibility does not impede fuel or debris removal activities.  The IWTS will


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 provide the necessary collection of contaminated basin water, treatment of the water, and return
 of treated water to all basin processes that require water, such as canister decapping, fuel
 retrieval, debris cleaning, and sludge retrieval.

 Water will be removed from the basins in accordance with the schedule requirements of the Tri-
 Party Agreement.  The IWTS will meet or be modified, as appropriate, so that treated water
 meets the ETF waste acceptance criteria.  The IWTS-treated water will be pumped into tanker
 trucks and transported to the ETF. The IWTS as designed by DOE shall be included in the
 RDR/RAWP subject to EPA approval.

 During SNF retrieval, some water will be removed with the SNF and trapped inside the MCOs.
 When the water is drained from the MCOs during later processing, it may be recycled to the
 basins and managed with the bulk of the contaminated water. This recycle will help maintain
 necessary water levels in the basins and reduce the volumes of wastewater generated.
 Alternately, the water may be treated as necessary and transferred directly to the ETF. Clean
 water will be added to the basins to maintain the water at the  level necessary to cool the SNF and
 provide radiation shielding hi the basins during remedial activities.

 The IWTS includes a pre-filter to remove particulate matter and an ion exchange module to
 remove remaining radioactive contaminants except tritium. Tritium cannot be effectively
 separated from water.  Prior to removal from the basins, water will be sampled to determine if it
 meets ETF waste acceptance criteria including the criterion for PCBs. If PCBs or other
 contaminants are detected at concentrations greater than the waste acceptance criteria at ETF,
 then additional treatment will be added to the IWTS to ensure that water leaving the system
 meets the waste acceptance criteria for ETF. Water removed  from the basin that is above a PCB
 concentration of 0.5 ppb will be a Toxics Substances Control Act (TSCA) regulated waste under
 40CFR761.79.

 ETF operating permits will be modified as necessary before K Basins water is received. The
 DOE shall submit all necessary information and applications for any modifications of permits in
 a timely manner to support the Tri-Party Agreement schedule. Note that operation of the ETF is
 not part of this CERCLA interim remedial action. Contaminants and by-products removed
 during the treatment process at the ETF  are concentrated and dried into a powder.  The powder
 generated at ETF from treating water generated under this interim remedial action is authorized
 for disposed at the ERDF if it (1) meets  the ERDF waste acceptance criteria, (2) the K Basins
 water is not combined with other liquid  effluent whose treatment residue is not authorized for
 ERDF disposal, and (3) the residue from treatment of K Basins water is not combined with waste
 that is not authorized for ERDF disposal.  Otherwise, the powder will be disposed at another
 authorized facility as per ETF operating permit(s).

 Operation of the IWTS and any other water treatment systems associated with this CERCLA
 interim remedial action will generate secondary wastes such as ion exchange modules and
 cartridge filters. Any carbon filters added  to provide PCB treatment would be managed as a
TSCA-regulated waste upon removal. All other components of the IWTS, such as ion exchange
modules, will be managed as debris.
                                         30

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  11.4   Selected Remedy for Debris

  Debris will be removed from the basins in accordance with the schedule requirements of the Tri-
  Party Agreement. Debris is solid waste resulting from this CERCLA interim remedial action,
  excluding SNF, sludge, and wastewater. Debris includes items located both above and below the
  water in the basins, wastes generated from operation and deactivation of the in-basin water and
  sludge treatment systems, and wastes generated during basin deactivation. Debris may also be
  generated during deactivation of sludge treatment facility(ies) or equipment done as part of this
  CERCLA interim remedial action.

  Debris will be removed from the K Basins, treated as appropriate, and disposed at the ERDF as
  approved by EPA.  If the debris cannot be treated to meet ERDF waste acceptance criteria, it
  will be transferred to a 200 Area waste management facility approved by EPA. If ERDF cannot
  be used, the EPA would approve use of the Central Waste Complex, Mixed Waste Trench (W-
  025), Low Level Burial Grounds, Waste Receiving and Processing facility, and T Plant as
 environmentally protective management facilities for the debris provided this waste and these
 facilities are managed in accordance with applicable requirements. The scope of this CERCLA
 interim remedial action for debris is removal from the basins, treatment, transport to ERDF for
 disposal or alternatively transferring the debris to an approved waste management facility
 appropriate for the designation. When the debris is received at the storage or disposal facility,
 further waste management is beyond  the scope of this interim remedial action.

 Debris will be removed from the basins throughout the course of the K Basins clean out and
 during deactivation of the basins and  sludge treatment systems for this CERCLA interim
 remedial action.  Some debris has been generated and packaged at the K Basins prior to issuance
 of this ROD. This waste may be disposed of at the ERDF if the packaged waste meets the ERDF
 waste acceptance criteria. Otherwise, it will be disposed  at another 200 Area facility approved
 by EPA. Debris treatment and disposal as designed by DOE shall be included in the
 RDR/RAWP subject to EPA approval.

 After removal, debris will be designated to determine if it should be handled as solid waste,
 dangerous waste, low level waste, low level mixed waste, TRU waste, or TRU mixed waste.
 Debris for which no reuse, recycle, or decontamination option is identified will be assigned an
 appropriate waste designation (e.g., solid, radioactive, dangerous, mixed).

 The debris is regulated as a PCB remediation waste where it has contacted sludge. As the
 underwater debris is removed from the basins it will be drained of free-flowing liquid and rinsed
 with water to remove the majority of sludge adhering to the debris.  Thereafter, the debris would
 be managed in accordance with applicable radioactive waste and dangerous waste requirements,
 but would no longer be designated or managed as a TSCA-regulated waste. The risk-based
 disposal approval under 40 CFR 761.61(c) is based on the expectation that minimal quantities
 and concentrations of PCBs will be left on the debris and  that management of this waste in
 accordance with applicable radioactive waste and dangerous waste requirements will be
protective of residual PCBs present in the waste. This decision will not pose an unreasonable
risk of injury to human health or the environment.  Further details on the analysis for this risk-
based disposal approval under 40 CFR 761.61(c) is contained in appendix C of the focused
feasibility study.


                                         31

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 11.5   Selected Remedy for Deactivation

 Once the SNF, sludge, water, and debris such as canisters are removed from the K Basins, the
 basins will be deactivated.  Deactivation will be completed in accordance with the schedule
 requirements of the Tri-Party Agreement.  Deactivation will remove additional hazardous
 materials and place the basins into a condition such that they can be maintained safely with
 minimal surveillance and maintenance until such time as interim safe storage and/or basin
 remedial activities are implemented. Deactivation includes the following activities:

 *      Equipment that is not an integral part of the basin structures will be drained, removed,
        decontaminated as appropriate, packaged, and disposed of as debris. Such equipment
        could include components of the SNF retrieval system, the IWTS, and the sludge retrieval
        system.
 *      Sludge treatment system equipment and the structure in which it is installed will be
        removed, decontaminated as appropriate,-packaged, and disposed as debris.
 *      The basin structure will be decontaminated to the extent required to meet criteria for
        minimal surveillance and maintenance set forth in the remedial design report and
        remedial action work plan, likely as an amendment.
 *      Support systems such as electrical, heating, ventilation, and air conditioning, water
        supply, and monitoring that  are not required for future environmental compliance or
       personnel safety will be de-energized.
 *     Structural repairs will be made as necessary for future surveillance and maintenance
       needs.
 *     Building penetrations will be sealed to prevent entry of animals, and personnel access
       controls will be maintained or installed by DOE.

Deactivation is several years in the future and activities needed to complete deactivation have not
been fully defined. The DOE will amend the RDR/RAWP subject to EPA approval to more fully
describe the activities when deactivation planning is complete. The DOE will provide the
amendment in a timely manner to support the Tri-Party Agreement schedule.

It is expected that the basins will still be radio logically contaminated at the end of deactivation,
but activity levels cannot be estimated at this tune. The contamination will be stabilized as part
of deactivation to prevent releases to the environment.

11.6 Institutional Controls

After deactivation, air and groundwater monitoring and controls to prevent public access will be
established or maintained by DOE as appropriate until such time as final remedial action is
completed. Current access controls  include signs along the river,  an 8-foot fence, locked access
to buildings containing the primary hazards, and routine patrols. Institutional controls will be
included in the RDR/RAWP subject to EPA approval.
                                          32

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                        XII. STATUTORY DETERMINATIONS

  Under CERCLA Section 121, selected remedies must be protective of human health and the
  environment, comply with ARARs, be cost effective, and utilize permanent solutions and
  alternative treatment technologies or resource recovery technologies to the maximum extent
  practical.  In addition, CERCLA includes a preference for remedies that employ treatment that
  significantly and permanently reduces the volume, toxicity, or mobility of hazardous substances
  as their principal element. This section discusses how the selected remedy meets these statutory
  requirements.

  The selected remedy provides the best balance of tradeoffs among the alternatives with respect to
  evaluation criteria that are used to evaluate remedies under CERCLA. The selected remedy will
  protect human health and the environment by removal of contaminants from the K Basins and
  transfer to environmentally protective facilities. It will comply with ARARs, is cost effective,
  and will utilize permanent solutions to the maximum extent practicable. The selected alternative
  satisfies the CERCLA preference for treatment as a principal element.

  12-1 Protection of Human Health and the Environment

 The selected remedy provides protection of human health and the environment by removing the
 contents of the K Basins and placing the hazardous substances in permitted protective facilities.
 The selected remedy will be conducted in compliance with identified ARARs, to-be-considered
 (TBC) materials, and As Low As Reasonably Achievable (ALARA) principals to minimize
 exposure to site workers and releases to the environment.

 12.2  Compliance with ARARs and TBC Materials.

 The selected remedy will comply with the federal and state ARARs and TBCs identified below.
 No waiver of any ARAR is being sought. This interim remedial action is part of a final remedial
 action that will satisfy other ARAR requirements when completed.  The chemical, action, and
 location-specific ARARs identified for the selected remedy are the following:

 The requirements for "Designation, Reportable Quantities, and Notification" (40 CFR 302)
 pursuant to CERCLA are applicable to new releases of CERCLA hazardous substances that
 occur during the K Basins interim remedial action. If new releases of hazardous substances
 exceeding the reportable quantities occur, agencies must be notified as appropriate.

 The substantive requirements of the "Dangerous Waste Regulations" (WAC 173-303) pursuant
 to the state Hazardous Waste Management Act (70.105 RCW) are applicable for the
 identification, treatment, storage, and disposal of dangerous and mixed wastes generated during
 the K Basins interim remedial action.  Dangerous waste management activities beyond the scope
 of the CERCLA action are subject to the full substantive and administrative requirements.

 The "Land Disposal Restrictions" (40 CFR 268) pursuant to the Resource Conservation and
Recovery Act (42 USC 6901, et seq.) are applicable for establishing treatment standards and
storage requirements prior to disposal of any dangerous or mixed wastes generated as part of the
                                         33

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 K Basins interim remedial action. The selected remedy for sludge storage is in accordance with
 40CFR268.50(e).

 The "Regulation of PCBs" (40 CFR 761) pursuant to the Toxic Substances Control Act (15 USC
 2601, et seq.~) is applicable to the management of sludge and debris removed from the K Basins.
 The sludge has been determined to be a PCB remediation waste and must be marked, stored,
 treated, and disposed in accordance with the PCB remediation waste requirements. Debris has
 been determined to be a PCB remediation waste where it has contacted sludge. This regulation is
 not applicable to debris that is treated as described in the selected remedy which includes a risk-
 based disposal approval as per 40 CFR 761.61(c). This regulation is not applicable to water
 leaving the basin systems after the water is treated as described in the selected remedy to below
 0.5  ppb.

 The "Nuclear Regulatory Standards for Protection Against Radiation" (10 CFR 20) pursuant to
 the Atomic Energy Act (42 USC 201 l,et seq.) and the "Radiation Protection Standards" (WAC
 246-221) pursuant to the State of Washington Radiation Protection Requirements (70.98 RCW)
 are relevant and appropriate to establishing public dose limits for activities implemented under
 the K Basins interim remedial action. Relevant and appropriate requirements are that the dose to
 an individual member of the public cannot exceed 0.1 rem/year (100 mrem/year) total effective
 dose equivalent and 2 mrem/hr from external exposure in unrestricted areas.

 The substantiate requirements in "Licensing Requirements for Land Disposal of Radioactive
 Waste" (10 CFR 61) pursuant to the Atomic Energy Act are relevant and appropriate to
 radioactive waste generated by the K Basins interim remedial action and taken for disposal at the
 Hanford Site. Relevant and appropriate requirements are the general prohibition on near-surface
 disposal of greater-than-Class-C radioactive waste and the general performance objectives stated
 in 10 CFR 61.40.

 The "Environmental Radiation Protection Standards for Nuclear Power  Operations" (40 CFR
 190) pursuant to the Atomic Energy Act are relevant and appropriate to the public dose associated
 with activities conducted as part of the K Basins interim remedial action. Relevant and
 appropriate requirements are those that limit dose to 25 mrem/year to whole body, 75 mrem/year
 to thyroid, and 25 mrem/year to any other organ,

 The  "Environmental Radiation Protection Standards for the Management and Disposal of Spent
 Nuclear Fuel, High-Level and Transuranic Radioactive Waste" (40  CFR 191) pursuant to the
Atomic Energy Act are applicable to the SNF and TRU waste generated by the K Basins interim
 remedial action.  On-site disposal of these materials is prohibited by this regulation.

The "Department of Energy Occupational Radiation Protection" (10 CFR 835) is applicable to
all activities undertaken as part of the K Basins interim remedial action and establishes a worker
dose limit of 5 rem/year total effective dose equivalent.

The "Hazardous Materials Regulation" (49 CFR 171) and "Hazardous Materials Tables" (49
CFR 172) pursuant to the Hazardous Materials Transportation Act (49 USC 1801-1813) are
applicable to any offsite transportation of potentially hazardous materials, including samples and
wastes generated by the K Basins interim  remedial action.


                                          34

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  The "Radiation Protection Air Emissions" (WAC 246^247) and the "National Emissions
  Standards for Hazardous Air Pollutants" (40 CFR 61) are applicable to airborne emissions of
  radipnuchdes.  The standard applies to the Hanford Site as a whole. Airborne emissions from K
  Basins activities must not cause the cumulative site emissions to exceed the site public dose limit
  of 10-mrem/year effective dose equivalent. In addition, WAC 246-247 requires a demonstration
  of best available radionuclide control technologies and monitoring as appropriate. The "Ambient
  Air Quality Standards and Emission Limits for Radionuclides" (WAC 173-480) are also
  applicable to airborne emissions of radionuclides. However, the limits of WAC 246-247 are
  more restrictive.  The DOE has been demonstrating compliance with WAC 246-247 via the
  notice of construction (NOC) process with EPA and the Washington State Department of Health
  The administrative requirements of WAC 246-247 are not an ARAR, so if in the future, the DOE
  determines that meeting the administrative requirements of the NOC process may jeopardize
  timely performance of this interim remedial action, the DOE may seek EPA approval to meet the
  substantiative but not the administrative requirements of WAC 246-247.

  The "National Emissions Standards for Asbestos, Standard for Demolition and Renovation" (40
  CFR 61.145-150) are applicable to management of asbestos-containing materials that might be
 generated during deactivation of the K Basins.

 The "Controls for New Sources of Toxic Air Pollutants" (WAC  173-460) are applicable to
 airborne emissions of toxic air pollutants from new and modified activities conducted at the K
 Basins. Quantities of toxic emissions must be quantified to establish acceptable levels, and best
 available control technologies must be applied.

 The National Historic Preservation Act (16 USC 470, et. seq.) and implementing regulations are
 applicable to those activities associated with the K Basins interim remedial action that might
 affect properties in the 100-K Area that may be eligible for listing on the National Register of
 Historic Places.  Appropriate protection of those properties is required.

 The National Archeological and Historical Preservation Act (16 USC 469a) and implementing
 regulations are applicable to those activities associated with the K Basins interim remedial action
 that might affect archeological or historic data in the 100-K Area. Appropriate responses are
 required in the event that artifacts are discovered.

 The Endangered Species Act (16 USC 1531, et. seq.) and implementing regulations are
 applicable to those activities associated with the K Basins interim remedial action that might
jeopardize any threatened or endangered species or habitats in the 100-K Area. Appropriate
 actions must be taken to protect species and habitats.

ThQ Hanford Reach Study Act (Public Law 100-605, as amended) is applicable because the K
Basins interim remedial action takes place near the Columbia River and requires minimizing and
providing  mitigation for direct and  adverse impacts on the river.

Other criteria, advisories, or guidance to be considered for the K Basins interim remedial action
are the following:
                                          35

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  Public dose limits of 100 mrem/year total effective dose equivalent proposed under the
  "Radiation Protection of the Public and the Environment" (10 CFR 834, proposed at 58 FR
  16268) are to be considered as limits for activities undertaken as part of the K Basins interim
  remedial action. Note that these TCB standards are the same standards as enforceable NRC  and
  State ARARs identified in this section.

  The Environmental Restoration Disposal Facility Waste Acceptance Criteria is to be considered
  in determining whether waste generated by the K Basins interim remedial action can be disposed
  at the facility.

  12.3 Cost Effectiveness

  The selected remedy provides overall effectiveness proportion to its cost. Treatment for final
  disposal of the K Basin sludge as a unique waste stream could not be cost effectively performed
  within the scope of this interim remedial action.  Therefore sludge will undergo minimal
  treatment necessary to support its interim  storage in the 200 Area for future final treatment as
  part of a much larger waste stream.  The selected remedy takes advantage of economies of scale
  by treating the K Basin sludge as part of the much larger quantity of remote-handled TRU waste
  at Hanford.

  12.4 Utilization of Permanent Solutions and Alternative Treatment Technologies to tne
     Maximum Extent Possible

 The selected remedy utilizes a permanent solution to mitigate the potential to release hazardous
 substances from the K Basins by removing their contents. The process of SNF retrieval,
 washing, loading in baskets, and loading into multi-canister overpacks utilizes numerous
 innovative remotely operated equipment.  Sludge that is treated and disposed at the ERDF will
 be a permanent solution for that sludge. The remaining sludge will be treated outside the scope
 of this interim remedial action. Water will be treated in the basins as part of this interim
 remedial action, and then transported to the ETF for final treatment and disposal beyond the
 scope of this interim remedial action. Debris, including deactivation waste, that is removed from
 the basins, treated as appropriate, and disposed at the ERDF will  be a permanent solution for
 debris.

 12.5 Preference for Treatment as a Principal Element

 The SNF, and its degradation products in the sludge, water, debris and deactivation waste are
 principal threats, as the term is defined in EPA guidance. While the selected remedy does not
 provide significant treatment of the SNF and sludge (except sludge treated for disposal at the
 ERDF), the  selected remedy does include transferring SNF and sludge to facilities where the
 waste will be treated. In addition, the selected remedy does provide treatment of the water at the
 basins, and transport to the ETF for final treatment. Debris, including deactivation waste, and
 any other waste for disposal at the ERDF will be treated, as appropriate, to meet ERDF waste
 acceptance criteria.  The final remedy for the principal threat wastes that is beyond the scope of
this interim remedial action will involve treatment.

12.6 CERCLA Section 104(d)(4) Determination


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 The preamble to the NCP indicates that when non-contiguous facilities are reasonably close to
 one another and wastes at these sites are compatible for a selected treatment or disposal
 approach, CERCLA Section 104(d)(4) allows the lead agency to treat these related facilities as
 one site for response purposes and, therefore, allows waste transfer between such non-contiguous
 facilities without having to obtain a permit.  The 100 K Area and the 200 Area are treated as one
 site for response purposes. This is consistent with all previous Hanford 100 Area RODs which
 required transfer of waste to the 200 Area.

 12.7 Off-Site Rule

 Some waste generated by the K Basins CERCLA action might be transported offsite for
 treatment or disposal, if offsite facilities provide a capability that is not available onsite. (For
 example, debris such as SNF canisters with a high dose rate may be sent to a permitted offsite
 commercial facility with a shielded crusher.  After crushing, the debris would be returned to the
 Hanford Site for disposal at the ERDF.) Under 40 CFR 300.440(a)(4), EPA must determine the
 acceptability of any offsite facility selected for the treatment, storage, or disposal of CERCLA
 waste.  In determining acceptability, EPA will consider the facility's compliance status and any
releases from the facility.  The need to utilize offsite facilities for waste generated by this
CERCLA action has not been established at this time.  If such need is identified in the future,
DOE will be required to obtain a determination of acceptability from EPA.
                                          37

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               XIII. DOCUMENTATION OF SIGNIFICANT CHANGES
              FROM PREFERRED ALTERNATIVE OF PROPOSED PLAN

 The sludge treatment alternatives were developed with the intent of treating the K Basins sludge
 as necessary for interim storage prior to final treatment and disposal.  The feasibility study
 showed there were implementability issues and high costs (see table 91) for all of the treatment
 alternatives. The proposed plan stated that the implementability issues might best be addressed
 by placing the sludge into interim storage, with treatment sufficient to meet interim storage
 requirements.  The interim storage would be at 200 Area permitted facilities. The sludge could
 then be treated to meet final storage and disposal requirements at a later time. Treatment of
 PCBs is specified in the proposed plan as a necessary step to meet interim storage requirements
 prior to final treatment and disposal. The selected remedy does not include such treatment
 because PCB treatment is will not be necessary to meet interim storage requirements due to
 changing acceptance criteria at the facilities.  The selected remedy could have been reasonably
 anticipated from the preferred alternative in the proposed plan regarding sludge treatment.

The selected remedy is different from the preferred alternative in the following ways:

 *     Sludge treatment prior to interim storage in the 200 Area has been moved outside the
       scope of the interim remedial action.
*      ?CBs m slud§e will not be treated prior to interim storage. Thus, at the conclusion of this
       interim remedial action, the sludge will still be a PCB remediation waste, as defined and
       regulated by TSCA.  Sludge will be stored as PCB/radioactive waste as per TSCA 40
       CFR 761.65(a), which specifies that the usual 1-year storage limit for PCB waste does
       not apply to PCB/radioactive waste if certain provisions are met.
 *      Further analysis of the waste acceptance criteria for double-shell tanks indicated the tanks
       would be a less viable option than portrayed in the proposed plan, due to
       implementability and cost. Therefore, the sludge storage facility will likely be a facility
       other than double-shell tanks.
*      Ongoing evaluation of the safety issues related to interim storage of the sludge have made
       storage without treatment a more viable option within the selected remedy than portrayed
       in the proposed plan.
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                             RESPONSIVENESS SUMMARY

                   I.  STAKEHOLDER ISSUES AND EPA RESPONSES

  Six individuals provided public comment in the form of five written comment letters and one
  oral comment.  There were 11 main ideas contained in the comments. They are identified by
  number below, including the EPA response.

  (1)    The experience and lessons learned from the clean out and deactivation of the N Reactor
        Basin should be Jully utilized for the K Basin effort.

        The N reactor at Hanford contains a fuel storage basin that contained SNF, sludge, water,
        and debns.  That basin has recently undergone a clean out and deactivation. A document
        titled, "Innovative Work Practices and Lessons Learned at the N Area Deactivation
        Project", was published in January 1999 by the contractor who conducted the N Basin
        work, and is included in the Administrative Record.  This document was reviewed in
        detail during a formal Lessons Learned session with managers for the deactivation and
        sludge projects  in the K Basins SNF Project.  Resolution of a number of issues
        encountered at N Basin will benefit the work to be done at K Basins. In addition, the
        SNF Project is using some of the same personnel who worked on the N Basin
        remediation. The SNF Project managers will maintain communication with the N Basin
        clean out and deactivation managers over the course of the fuel removal and remediation
        of K Basins.

 (2)     All opportunities for early removal of debris or sludge should be used.

        The legally-enforceable schedule for the K Basins project has SNF removal preceding
        sludge and debris removal. However routine operations and initial cleanup activities"
        have been removing debris, for example 2,000 empty canisters were removed in 1998. It
        is anticipated that debris removal will be an ongoing activity as it simplifies basin
        operations.  The sludge that is anticipated to be the most chemically reactive and most
       radioactive is the sludge produced during the fuel washing. This sludge will be captured
       by the IWTS and stored in settling tanks in the basin which provide additional isolation
       from the environment. For the K-West basin this will be nearly all of the sludge. For the
       K-East basin, we continue to examine the feasibility of removing a portion of the sludge
       prior to SNF removal if the necessary steps to get it to and received at a 200 Area facility
       are in place in time. Regardless of whether early sludge removal is achieved, there will
       be sludge within and under fuel canisters and debris that won't be accessible until the
       final stages of the K Basins project.

(3)     As much sludge as possible should be treated to final disposal requirements to minimize
       interim storage.  (See answer to comment #4).

(4)     The sludge option for minimal treatment and disposal at the ERDF or transfer to double-
       shell tanks should be utilized to the maximum extent and as soon as possible.
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        Although actual costs for interim storage of K Basins sludge in the 200 Area have not
        been estimated, it will be expensive based on experience with storing other wastes at
        Hanford. Therefore, financially viable opportunities to isolate non-TRU fractions for
        treatment and final disposal in the ERDF will be pursued. Sludge will be stored hi
        existing permitted facilities hi the 200 Area to avoid the cost of building a new facility.
        TRU sludge that can easily be accepted into double-shell tanks will be (although at this
        time this does not appear to be probable).  Financially viable opportunities to treat sludge
        for final disposal to WIPP and avoid interim storage will be pursued (although at this
        time this does not appear to be probable).

 (5)     What level of quality assurance will DOE use for the K Basins project to protect the
       public?

        The DOE has classified the K Basins as a nuclear facility. DOE requires the contractor
        responsible for a nuclear facility to conduct its work in accordance with a quality
        assurance program that meets the criteria of 10 CFR §830.120. The criteria of 10 CFR
        §830.120 are applied to facility systems and components using a graded approach. The
       graded approach ensures the appropriate level of quality assurance is applied based on
       factors such as relative importance to safety and the magnitude of any hazard involved.
       The contractor is also required by 10 CFR §830.120 to use appropriate standards to
       develop and implement its quality assurance program.  The standards which the SNF
       Project uses to develop and implement its quality assurance program include the
       American Society of Mechanical Engineers NQA-1 standard and the DOE Office of
       Civilian Radioactive Waste Management Quality Assurance Requirements and
       Description DOE/RW/0333P standard. Using the graded approach, the SNF Project
       Quality Assurance Program applies requirements from these quality assurance standards
       to protect workers, the public, and the environment.

(6)    Support was expressed to conduct the remedial action to protect the environment
       including the Columbia River from releases from the basins.

       There has been strong community support to conduct the interim remedial action to
       remove the material and waste from  the K Basins.

(7)    Minimize infrastructure development for sludge treatment.

       In July 1999, the Department  of Energy approved a sludge treatment path forward
       recommendation. The recommendation included integrating sludge treatment with other
       similar waste at the Hanford Site.  This recommendation is consistent with the goal of
       minimizing infrastructure development. This approach allows for separation of different
       fractions of sludge, and treating each fraction as appropriate. The approach also provides
       the flexibility to separate and store sludge in a safe and environmentally sound manner.
       This interim storage allows for a sitewide economy of scale by developing a treatment
       process to deal with the K Basin sludge in the same manner as other transuranic waste on
       the Hanford Site rather than building a facility solely for the purpose of treating K Basin
       sludge.  The consolidation of K Basin sludge with other similar waste on the Hanford Site
       provides opportunities for infrastructure minimization on a Sitewide basis.


                                          40

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(8)    Minimize waste going to the ERDF to minimize ERDF's expansion into sage/steppe
      habitat.

      Regarding minimizing waste going to the ERDF to minimize the footprint of the ERDF
      on the habitat, the volume of waste from the K Basins action is very small relative to
      other cleanup projects. The environmental benefit resulting from removal of waste from
      the K Basins outweighs the contribution of this action to the habitat impact hi the 200
      Area.
                                                                     resources.
 (9)     Conduct the project in a manner that protects ecological and cultural

        An ecological and cultural resource review was done as part of the K Basins EIS and
        Supplement Analysis. The EIS concluded that no threatened or endangered species or
        cultural resources would be directly affected by construction activities. The analyses and
        decisions made in the EIS were adopted into the Focused Feasibility Study.

       Additionally, as the K Basin Interim Remedial Action proceeds, DOE must comply with
       all applicable or relevant and appropriate requirements. These requirements include the
       National Historic Preservation Act, the National Archeological and Historical
       Preservation Act, and the Endangered Species Act. Compliance with these requirements
       will ensure that the cultural and ecological resources are appropriately protected.

(10)   Explain how releases from the basins will be addressed.

       This topic is covered hi Section IV "Scope and Role of Response Action Within Site
       Strategy" of this ROD.

(11)    Lack of technical specifics or cost for sludge storage made public comment difficult. The
       DOE should have known by now what to do with the sludge.

       The DOE did have a baseline chemical treatment process for the sludge treatment.
       However, it was not until sludge characterization was completed and the baseline process
       was further developed, that the full cost of the chemical treatment process could be
       calculated. It was the high cost of treating all of the sludge via the basehne process  that
       led to additional analysis to find a better, more cost effective way to manage sludge.

       Specific technical details were not available for many of the alternatives in the Focused
       Feasibility Study since treating the sludge is a unique application of these technologies
       that involves extensive development prior to implementation. The DOE did not have a
       completed Conceptual Design Process for the various alternatives prior to the submittal
       of the Feasibility Study and Proposed Plan and therefore the design details were not
       available. Based on the information analyzed, however, the DOE concluded that utilizing
       one single process for all of the K Basin sludge streams would be very expensive and nof
      cost effective.  The preferred alternative, as specified in the Proposed Plan,  was
      developed to allow the use of combinations of treatment alternatives to maximize
      flexibility and minimize costs.  This alternative also includes an interim storage period
                                        41

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       that will allow for a sitewide economy of scale by developing a treatment process to deal
       with the K Basin sludge hi the same manner as other transuranic material on site.
                       H.  TECHNICAL AND LEGAL ISSUES

The technical issues were covered hi the above comments and responses. There were no legal
issues.
                                       42

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                                      GLOSSARY

 Canister Storage Building - A new facility located in the 200 East Area of the Hanford Site that
       will be used for underground vault storage of SNF.
 Central Waste Complex - A RCRA interim status mixed waste treatment and storage facility
       located in the 200 West Area of the Hanford Site..
 Cold Vacuum Drying Facility - A facility located in the 100-K Area that will be used for drying
       SNF to make it safe for interim storage at the canister storage building.
 Deactivation - Actions taken to place a facility into a radiologically and environmentally safe
       condition such that it can be decontaminated and decommissioned at a later date.
 Double-Shell Tanks - RCRA interim status underground tanks located in the 200 East and 200
       West Areas of the Hanford Site. Tanks are double-contained and have leak detection
       capabilities.
 Environmental Restoration Disposal Facility - A near-surface landfill located in the 200 West
       Area, designed for permanent disposal of wastes generated under Hanford Site CERCLA
       documents. The ERDF is double-lined and was authorized via a 1995 CERCLA ROD.  ,
 Effluent Treatment Facility - A RCRA-permitted wastewater treatment facility in the 200 East
       Area of the Hanford Site. Liquid radioactive and mixed waste is treated to  meet
       discharge standards for disposal to the soil.
Low Level Burial Grounds - Unlined, near-surface landfills located in the 200 East and 200 West
       Areas of the Hanford Site, designated for disposal of low-level radioactive wastes.  The
       low-level burial grounds are RCRA interim status units but are no longer allowed to
       receive dangerous or mixed wastes.
Mixed Waste Trench (W-025) - A RCRA interim status near-surface landfill located in the 200
       West Area of the Hanford Site, designated for storage and disposal of mixed wastes. The
       mixed waste trench is double-lined.
 TRU waste - A radioactive waste that contains greater than 100 nanocuries per gram of
       transuranic radionuclides with a half life of greater than 20 years.  TRU waste will
       ultimately be disposed off-site at the WIPP.
T Plant - A RCRA interim status mixed waste treatment and storage facility located in the 200
       West Area.  It is currently used as a decontamination facility, but is a potential sludge
       storage and treatment facility.
 Waste Receiving and Processing Facility - A RCRA interim status storage and treatment facility
       located in the 200 West Area.  It is used specifically to package and treat TRU and mixed
       TRU wastes.
Waste Isolation Pilot Plant - A RCRA-permitted deep geologic disposal facility for TRU waste
       located in New Mexico.
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