POLICY ISSUE NEGATIVE CONSENT

POLICY ISSUE
NEGATIVE CONSENT
June 21, 2002
SECY-02-0112
FOR:
The Commissioners
FROM:
William D. Travers
Executive Director for Operations
SUBJECT:
NRC REVIEW OF IDAHO NATIONAL ENGINEERING AND
ENVIRONMENTAL LABORATORY DRAFT INCIDENTAL WASTE
(WASTE INCIDENTAL TO REPROCESSING) DETERMINATION FOR
SODIUM-BEARING WASTE
PURPOSE:
To inform the Commission that the staff plans to transmit the attached letter (see Attachment),
unless instructed otherwise by the Commission, from the Director of the Division of Waste
Management, U.S. Nuclear Regulatory Commission (NRC), to the Director of Idaho Nuclear
Technology and Engineering Center (INTEC) Waste Programs, U.S. Department of Energy
(DOE), at the Idaho Operations Office (ID). The proposed letter provides the results of the
NRC staff’s review of the Idaho National Engineering and Environmental Laboratory (INEEL)
draft incidental waste [or waste incidental to reprocessing (WIR)] determination regarding the
management of sodium-bearing waste as transuranic (TRU) waste.
SUMMARY:
This paper discusses DOE-ID’s WIR determination regarding management of sodium-bearing
waste as TRU waste. This paper also summarizes the results of the staff’s review of the
determination. The details of the staff’s review, including conclusions and recommendations,
are located in the technical evaluation report, attached to the proposed response to DOE-ID
(see Attachment).
CONTACTS:
Kristina L. Banovac, NMSS/DWM
301-415-5114
David W. Esh, NMSS/DWM
301-415-6705
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BACKGROUND:
Since 1969, NRC has recognized the concept of incidental waste or WIR, concluding that
certain material that otherwise would be classified as high-level radioactive waste (HLW) need
not be disposed of as HLW and sent to a geologic repository, because the residual radioactive
contamination after decommissioning is sufficiently low as not to represent a hazard to the
public health and safety. Consequently, incidental waste is not considered HLW.
Incidental waste criteria were previously developed for management of certain wastes
removed from tanks at DOE’s Hanford site. The Commission approved these criteria in a Staff
Requirements Memorandum (SRM) dated February 16, 1993, in response to SECY-92-391,
“Denial of PRM 60-4 - Petition for Rulemaking from the States of Washington and Oregon
Regarding Classification of Radioactive Waste at Hanford.” These criteria are described in a
letter from R. Bernero/NRC, to J. Lytle/DOE, dated March 2, 1993. More recently, the criteria,
as modified, were included in the “Final Policy Statement: Decommissioning Criteria for the
West Valley Demonstration Project,” dated February 1, 2002 (67 FR 5003). In the Policy
Statement, the Commission noted the criteria that should be applied to the incidental waste
determinations at West Valley: (1) the waste should be processed (or should be further
processed) to remove key radionuclides to the maximum extent that is technically and
economically practical; and (2) the waste should be managed so that safety requirements
comparable to the performance objectives in 10 CFR Part 61, Subpart C, are satisfied.
In July 1999, DOE issued DOE Order 435.1, “Radioactive Waste Management,” and the
associated manual and guidance, which requires that all DOE radioactive waste be managed
as HLW, TRU waste, or low-level radioactive waste (LLW). The Order states that waste,
determined to be incidental to reprocessing, is not HLW and shall be managed in accordance
with the requirements for TRU waste or LLW, if it meets appropriate criteria. The Order
discusses the WIR evaluation process, stating that incidental waste may be managed as TRU
waste if the wastes: “...(1) have been processed, or will be processed, to remove key
radionuclides to the maximum extent that is technically and economically practical; and (2) will
be incorporated in a solid physical form and meet alternative requirements for waste
classification and characteristics, as DOE may authorize; and (3) are managed pursuant to
DOE’s authority under the Atomic Energy Act of 1954, as amended, in accordance with the
provisions of Chapter III of this Manual [“Transuranic Waste Requirements”], as appropriate.”
The guidance document for DOE Order 435.1 recommends consultation with NRC for
WIR determinations.
DISCUSSION:
On February 7, 2001, DOE-ID requested NRC consultation on, and review of, two draft
incidental waste determinations for INEEL. The first WIR determination involves waste
currently stored in the Tank Farm Facility located within the INTEC at INEEL and addresses
whether this waste may be managed as TRU waste. The second WIR determination
addresses the decontamination and closure of tanks used to store liquid HLW and sodiumbearing waste; the determination evaluates whether the tanks and tank residuals may be
managed as LLW. This paper focuses on the first determination only; the staff plans to
provide the Commission with the results of its review of the second determination at a later
date. DOE-ID is planning to remove, treat, and dispose of the waste, which mostly consists of
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decontamination solutions from spent fuel reprocessing maintenance and closure activities.
The decontamination solutions contain large quantities of sodium salts; therefore, this waste is
designated “sodium-bearing waste” (SBW). SBW also consists of second- and third-cycle
reprocessing extraction wastes, contamination from first-cycle reprocessing extraction wastes,
settled solids in the tanks, and liquid wastes from ongoing and future maintenance and closure
activities at the INTEC. DOE-ID developed a WIR determination to evaluate whether the SBW
may be managed as TRU waste and disposed of at the Waste Isolation Pilot Plant (WIPP),
rather than HLW.
In the Memorandum from William D. Travers, Executive Director for Operations, to the
Commissioners, dated June 18, 2001, the staff notified the Commission of its plans to review
the determinations and provide its recommendations to the Commission. After receiving no
objection from the Commission, NRC and DOE-ID staffs developed a Memorandum of
Understanding (MOU) that established the framework for NRC to provide technical assistance
to DOE-ID in regard to the incidental waste determinations (see SECY-01-0150,
“Memorandum of Understanding and Interagency Agreement between the U.S. Department of
Energy and the U.S. Nuclear Regulatory Commission on the Review of Incidental Waste
Determinations for the Idaho National Engineering and Environmental Laboratory,” dated
August 6, 2001, and related SRM, dated August 29, 2001). An Interagency Agreement (IA)
implements the MOU and establishes that all costs incurred by NRC, including contractor
support, will be reimbursed by DOE-ID. In addition, the MOU establishes that NRC’s activities
under the MOU are carried out in an advisory capacity, and that any advice given to DOE-ID
under the MOU does not constitute regulatory approval, authorization, or license for DOE
activities. The MOU and IA became effective on September 7, 2001.
On September 25, 2001, DOE-ID submitted the draft “Idaho Nuclear Technology and
Engineering Center Sodium-Bearing Waste -- Waste-Incidental-to-Reprocessing
Determination Report,” for NRC review. As noted in the June 18, 2001, Memorandum, NRC’s
review focused on Criterion 1, assessing whether the waste has been processed, or will be
processed, to remove key radionuclides to the maximum extent that is technically and
economically practical. Since NRC’s incidental waste guidance does not include a TRU
disposal option, NRC staff considers it inappropriate to assess whether the TRU disposal
option provides safety equivalent to the performance objectives of Part 61, since WIPP is
regulated by the U.S. Environmental Protection Agency and is outside of NRC’s jurisdiction.
Therefore, although the WIR determination addresses all three criteria in DOE Order 435.1,
NRC staff will not provide conclusions and recommendations for the TRU disposal portion of
the determination (Criteria 2 and 3). Rather, NRC will only provide comments and
observations on the methodology for meeting Criteria 2 and 3, that were identified during the
review.
After initial review of the determination, NRC staff provided DOE-ID with a list of questions and
comments in a request for additional information (RAI), dated December 12, 2001, to obtain the
necessary information needed to complete its review. In response to NRC’s observations and a
change in direction for a preferred alternative for SBW treatment in the development of the
Idaho High-Level Waste and Facilities Disposition Environmental Impact Statement, DOE-ID
decided to revise its approach taken in the SBW WIR determination. DOE-ID responded to
NRC’s RAI on January 29, 2002, providing the additional information requested and
summarizing the revised approach for the determination. The response explained that the
revised determination would present a range of SBW direct stabilization options as a base
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case, with an evaluation of the technical and economic practicality of additional key radionuclide
removal prior to disposal. In addition, the determination would identify the key radionuclides as
those that are important in meeting disposal performance objectives at WIPP.
On March 8, 2002, DOE-ID submitted the revised determination for NRC review. The revised
determination states that DOE Order 435.1 provides flexibility for each site to identify key
radionuclides as those that significantly impact disposal site performance objectives. This riskinformed approach allows DOE-ID to identify the key radionuclides for SBW treatment and
disposal and focus its technical and economic analysis on those radionuclides that are
important for meeting disposal performance objectives at WIPP, which require reasonable
assurance that exposure to humans is within established limits (40 CFR Part 191). DOE-ID
determined that americium (Am)-241, plutonium (Pu)-238, Pu-239, and Pu-240 are the key
radionuclides, since they account for most of the calculated future risk in WIPP’s performance
assessment. In addition, DOE-ID noted that 96 percent of the key radionuclides and 99
percent of all radionuclides generated from spent fuel reprocessing have been removed from
INTEC tank farm waste.
The revised determination presents a range of SBW direct stabilization options as a base
case, including contact-handled TRU grout, calcination, steam reforming, and direct
vitrification. The cost estimates (using only discriminatory costs -- costs that were considered
to be essentially the same for each option were not incorporated in the cost analysis) of the
direct stabilization options range from $566 million to $1359 million.
The revised determination treats SBW liquid and solids independently, by assuming that SBW
solids are filtered from the process feed stream and treated separately. The filtered solids,
including those from the tank heel removal, would be dried and packaged to meet WIPP waste
acceptance criteria as remote-handled TRU waste. Further dissolution of solids would be
necessary to make chemical separation of key radionuclides possible. However, because the
solids have been exposed to the very acidic SBW liquid for a long period of time, further
dissolution would be difficult, if not impossible. It is possible that strong acid mixtures at high
temperatures could dissolve some constituents in the SBW solids; however, no productionscale technologies exist, and because of the relatively small solids quantity and the severe
conditions anticipated for dissolution, it was not technically practical to develop a dissolution
process. Therefore, since no technologies have been demonstrated for dissolving SBW
solids, additional key radionuclide removal is considered to be not technically practical.
DOE-ID determined that it was technically possible to separate and remove additional key
radionuclides from SBW liquids using various solvent extraction options. The solvent
extraction options considered were TRU solvent extraction (TRUEX) and universal solvent
extraction (UNEX). TRUEX removes actinides including transuranic radionuclides, which
would be concentrated by evaporation and vitrified for eventual disposal at the HLW geologic
repository. DOE-ID estimates that TRUEX could remove 100 terabecquerels (TBq) [3000
curies (Ci)] of key radionuclides from the SBW liquid, given its high separation efficiency. The
bulk waste from the process would be concentrated by evaporation and grouted to produce a
remote-handled low-activity waste, expected to be suitable for disposal as Class C LLW. The
UNEX process is very similar to the TRUEX process; in addition, it removes cesium and
strontium isotopes. Since the UNEX process removes cesium and strontium, the bulk waste
from the process, after concentration and grouting, is expected to be suitable for Class A LLW
disposal.
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Since the solvent extraction methods of further key radionuclide removal were considered
technically practical, they were retained for further economic evaluation. The economic
practicality of removing additional key radionuclides from SBW liquid was evaluated by
determining removal costs (using TRUEX and UNEX processes) and considering the effect of
removing additional key radionuclides on reducing radionuclide releases to the public at WIPP.
The total project costs for TRUEX and UNEX processes are based on the design and
construction of a complex of new facilities at INTEC to further process the SBW to remove and
treat additional key radionuclides. The total discriminatory cost estimate for UNEX is $1732
million; the total discriminatory cost estimate for TRUEX is $2779 million. This is $373 million
to $2213 million above the cost of the direct stabilization options, or $124,000 to $738,000 per
curie for additional key radionuclide removal (assuming TRUEX and UNEX remove 3000
additional curies of key radionuclides).
The WIPP Compliance Certification Application and supporting performance assessment
modeled TRU components from all waste planned for disposal. The performance assessment
for WIPP estimates that the source term of key radionuclides is 1.51x105 TBq (4,070,000 Ci)
from all sources at closure. The key radionuclide (Am-241, Pu-238, Pu-239, and Pu-240)
source term from the SBW is estimated at 170 TBq (4500 Ci). It is estimated that the UNEX
and TRUEX processes could remove an additional 100 TBq (3000 Ci) of key radionuclides
from the SBW liquid, which is less than 0.1 percent of the total WIPP curies at closure. Since
the large additional cost to remove 100 TBq (3000 Ci) of key radionuclides would not result in
a significant reduction of the radionuclide inventory at WIPP, DOE-ID determined that it was
not economically practical to remove additional key radionuclides from the SBW.
The details of the staff’s review, including conclusions and recommendations, are located in
the technical evaluation report, attached to the proposed response to DOE-ID (see
Attachment). The conclusions and recommendations are summarized below.
CONCLUSIONS AND RECOMMENDATIONS:
Based on the staff’s review of the information provided by DOE-ID, the proposed staff
response to DOE-ID indicates that NRC staff agrees that it is not technically practical to
remove additional key radionuclides from the SBW solids prior to disposal. NRC staff agrees
that even though the technology exists to remove additional key radionuclides from SBW
liquid, it is not economically practical, since removing additional key radionuclides for disposal
at a HLW geologic repository would not significantly reduce the radionuclide inventory at
WIPP. Therefore, NRC staff agrees that the SBW has been processed to remove key
radionuclides to the maximum extent practical. The proposed response to DOE-ID indicates
that NRC staff, in its role of providing technical assistance and acting in an advisory capacity
and not providing regulatory approval in this action, reviewed DOE-ID’s SBW WIR
determination and concludes that Criterion 1 has been met. This conclusion is dependent on
DOE-ID satisfactorily addressing the staff recommendations presented in the technical
evaluation report.
Unless otherwise directed by the Commission within 10 days, the staff plans to send the
attached proposed letter response and technical evaluation report to DOE-ID. The staff
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considers this action to be within the delegated authority of the Director of the Office of
Nuclear Material Safety and Safeguards, since the staff’s review of the SBW WIR
determination only assesses Criterion 1, and the staff is not making a determination regarding
protection of public health and safety and the environment. However, action will not be taken
until the SRM
is received.
It is noted that NRC will provide comments regarding protection of public health and safety and
the environment for the INEEL tank closure determination, which addresses the closure of
tanks used to store HLW and SBW and evaluates whether the tanks and tank residuals may
be managed as LLW. Therefore, the staff plans to provide its conclusions and
recommendations on the tank closure determination to the Commission for approval.
COORDINATION:
The Office of the General Counsel has reviewed this paper and has no legal objections.
/RA/
William D. Travers
Executive Director
for Operations
Attachment: Proposed ltr response fr J.T. Greeves/NRC to J.T. Case/DOE-ID,
“NRC Review of Idaho National Engineering and Environmental Laboratory Draft Waste
Incidental to Reprocessing Determination for Sodium-Bearing Waste - Conclusions and
Recommendations”
Mr. Joel T. Case, Director
INTEC Waste Programs
U.S. Department of Energy
Idaho Operations Office
850 Energy Drive
Idaho Falls, ID 83401-1563
SUBJECT:
NRC REVIEW OF IDAHO NATIONAL ENGINEERING AND ENVIRONMENTAL
LABORATORY DRAFT WASTE INCIDENTAL TO REPROCESSING
DETERMINATION FOR SODIUM-BEARING WASTE - CONCLUSIONS AND
RECOMMENDATIONS
Dear Mr. Case:
The U.S. Nuclear Regulatory Commission (NRC) has completed its review of the waste
incidental to reprocessing (WIR) determination for sodium-bearing waste (SBW) removed from
waste storage tanks at the Idaho Nuclear Technology and Engineering Center at the Idaho
National Engineering and Environmental Laboratory. As established in the Memorandum of
Understanding between the U.S. Department of Energy (DOE) and NRC, dated September 7,
2001, NRC’s activities related to the review are being carried out in an advisory capacity, and
any advice given to DOE’s Idaho Operations Office (ID) does not constitute a regulatory
approval, authorization, or license for DOE activities.
Your letter, dated February 7, 2001, requested NRC review of two WIR determinations, the first
addressing management of SBW as transuranic (TRU) waste. The second determination,
regarding tank closure, will be addressed by NRC separately. DOE-ID requested that NRC
review the SBW determination to the criteria set forth in DOE Order 435.1, “Radioactive Waste
Management.” The Order and its associated manual and guidance discuss the WIR evaluation
process, stating that incidental waste may be managed as TRU waste if the wastes: “...(1) have
been processed, or will be processed, to remove key radionuclides to the maximum extent that
is technically and economically practical; and (2) will be incorporated in a solid physical form
and meet alternative requirements for waste classification and characteristics, as DOE may
authorize; and (3) are managed pursuant to DOE’s authority under the Atomic Energy Act of
1954, as amended, in accordance with the provisions of Chapter III of this Manual [“Transuranic
Waste Requirements”], as appropriate.” NRC’s review focused on Criterion 1, assessing
whether the waste has been processed, or will be processed, to remove key radionuclides to
the maximum extent that is technically and economically practical. NRC’s incidental waste
guidance does not include a TRU disposal option. Therefore, NRC staff considers it
inappropriate to assess whether the TRU disposal option provides safety equivalent to the
performance objectives of 10 CFR Part 61, since the Waste Isolation Pilot Plant (WIPP) is
regulated by the U.S. Environmental Protection Agency and is outside of NRC’s jurisdiction.
Although the WIR determination addresses all three criteria in DOE Order 435.1, NRC staff is
not providing conclusions and recommendations for the TRU disposal portion of the
Attachment
J.T. Case
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determination (Criteria 2 and 3). Rather, NRC is only providing comments and observations on
the methodology for meeting Criteria 2 and 3, that were identified during the review.
NRC staff’s review initially focused on the information submitted by DOE-ID on September 25,
2001(letter from J.T. Case/DOE-ID to J.T. Greeves/NRC), including the “Idaho Nuclear
Technology and Engineering Center Sodium-Bearing Waste -- Waste-Incidental-toReprocessing Determination Report, Draft A,” and additional documents. NRC also reviewed
the responses to the request for additional information (RAI) (letter from J. Case/DOE-ID to
C.E. Abrams/NRC, dated January 29, 2002). After DOE-ID decided to revise its approach
taken in the SBW WIR determination, NRC staff concentrated its review on the revised SBW
WIR determination, submitted on March 8, 2002, which included the following: (1) “Idaho
Nuclear Technology and Engineering Center Sodium-Bearing Waste -- Waste-Incidental-toReprocessing Determination Report, Draft B”; (2) “Engineering Design File -- Supporting Cost
Data for the SBW Waste Incidental to Reprocessing Evaluation”; (3) “Sandia National
Laboratories Waste Isolation Pilot Plant -- RH-TRU Impact Assessment with PAVT Baseline
(RHVT)”; (4) “Engineering Design File -- Validation of Radionuclide Mass Balance Used in the
INTEC SBW WIR Determination Report”; and (5) “Engineering Design File -- Comparison of
Candidate Waste Streams to WIPP Waste Acceptance Criteria.” NRC staff also reviewed
additional information received through informal communications between DOE-ID and NRC.
The results of the NRC staff review are included in the technical evaluation report (see
Attachment) and are summarized below.
Based on NRC staff’s review of the information provided by DOE-ID, NRC staff agrees that it is
not technically practical to remove additional key radionuclides from the SBW solids prior to
disposal. NRC staff agrees that even though the technology exists to remove additional key
radionuclides from SBW liquid, it is not economically practical, since removing additional key
radionuclides for disposal at a high-level waste geologic repository would not significantly
reduce the radionuclide inventory at WIPP. Therefore, NRC staff agrees that the SBW has
been processed to remove key radionuclides to the maximum extent practical. NRC staff, in its
role of providing technical assistance to DOE-ID and acting in an advisory capacity and not
providing regulatory approval in this action, concludes that Criterion 1 has been met. This
conclusion is dependent on DOE-ID addressing the staff recommendations included in the
technical evaluation report and summarized below.
Although there have been significant efforts to develop the SBW liquid and solid radionuclide
concentrations, limited information is available in some key areas. The residual uncertainty can
likely be reduced through the collection of additional information during future activities
(e.g., solid and liquid sampling). For the SBW WIR determination, the residual uncertainty is
not expected to be significant enough to invalidate DOE-ID’s conclusion that SBW is WIR that
can be managed as TRU waste. However, as additional information is collected, an impact
assessment on the SBW WIR determination should be completed and any significant impacts
communicated to NRC. The residual uncertainty regarding the radionuclide inventory is
expected to be an area of interest to the NRC staff with respect to its impact on DOE-ID’s WIR
determination for tank closure. NRC plans to address this issue in a future RAI on the tank
closure WIR determination.
NRC’s RAI requested DOE-ID to provide a brief analysis describing impacts to workers from the
SBW treatment options evaluated. DOE-ID provided adequate information in its response to
J.T. Case
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the RAI and noted that this discussion would be included in the revised SBW WIR
determination. It appears that this information was not included; NRC recommends that DOEID provide a brief analysis discussing worker doses in the final SBW WIR determination.
Although the NRC staff review of the SBW WIR determination focused on Criterion 1, the staff
also noted the following during its review. NRC staff suggests that, if there are changes to
plans to permit WIPP to accept remote-handled (RH) TRU waste, or if the draft waste
acceptance criteria (WAC) for RH-TRU waste change, DOE-ID should revisit the WIR
determination before final decisions regarding the SBW treatment process and final waste
forms are made. NRC staff supports DOE-ID using the most economically efficient technology
that will result in waste that meets the WIPP WAC and supports DOE using a risk-informed
approach for the WIR determinations.
If you have any questions regarding this letter or the attached technical evaluation report,
please contact Kristina Banovac of my staff at (301) 415-5114, or David Esh at (301) 415-6705.
Sincerely,
John T. Greeves, Director
Division of Waste Management
Office of Nuclear Material Safety
and Safeguards
Attachment:
“U.S. Nuclear Regulatory Commission Review of the Idaho National Engineering and
Environmental Laboratory Draft Waste Incidental to Reprocessing Determination for
Sodium-Bearing Waste”
cc:
K. Lockie/DOE-ID
K. Picha/DOE-EM
R. Bernero
J. Contardi/DNFSB
B. Gannon/SAIC
U.S. NUCLEAR REGULATORY COMMISSION REVIEW
OF THE IDAHO NATIONAL ENGINEERING AND ENVIRONMENTAL LABORATORY
DRAFT WASTE INCIDENTAL TO REPROCESSING DETERMINATION
FOR SODIUM-BEARING WASTE
TABLE OF CONTENTS
LIST OF TABLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii
LIST OF FIGURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii
INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Background - History of Reprocessing Activities at the Idaho National Engineering and
Environmental Laboratory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Incidental Waste/Waste Incidental to Reprocessing Criteria . . . . . . . . . . . . . . . . . . . . . . . . 4
Review Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
CRITERION ONE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Original SBW WIR Determination (Draft A) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Revised SBW WIR Determination (Draft B) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Base Case . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
CH-TRU Grout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Calcination with Maximum Achievable Control Technology
Upgrade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Steam Reforming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Direct Vitrification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Waste Inventory and Characterization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Technical Practicality of Further Key Radionuclide Removal . . . . . . . . . . . . . . . . 11
Solids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Liquids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Economic Practicality of Further Key Radionuclide Removal . . . . . . . . . . . . . . . . 12
NRC REVIEW AND CONCLUSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
LIST OF ABBREVIATIONS AND ACRONYMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
LIST OF TABLES
Table 1: SBW treatment alternative costs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Table 2: Waste generation quantities for SBW disposal options . . . . . . . . . . . . . . . . . . . . . . . . . . 9
LIST OF FIGURES
Figure 1: INTEC area plot plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Figure 2: Plan view of Tank Farm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
ii
INTRODUCTION
Background - History of Reprocessing Activities at the Idaho National Engineering and
Environmental Laboratory
The Idaho National Engineering and Environmental Laboratory (INEEL), an 2300-square
kilometer (890-square mile) site, located in Eastern Idaho, was initially established to develop
civilian and defense nuclear reactor technologies. The Idaho Nuclear Technology and
Engineering Center (INTEC) at the INEEL was established in 1953 to recover fissile uranium by
reprocessing spent nuclear fuel (see Figure 1). The spent fuel was dissolved, producing an
acidic aqueous solution, which was processed through a first-cycle extraction system to
separate uranium from the bulk of the fission products (or first-cycle extraction waste). The
separated uranium was processed through a second- and third- cycle extraction system to
remove carry-over radioactive material, which included plutonium and transuranic radionuclides.
In 1992, the U.S. Department of Energy (DOE) Idaho Operations Office (ID) ceased
reprocessing activities at INTEC.
The waste from spent fuel reprocessing was stored in the Tank Farm Facility [consisting of
eleven 1000 cubic meter (m3) (300,000 gallon) and four 100 m3 (30,000 gallon) underground
storage tanks], where first-cycle solvent extraction waste was initially stored separately from
other reprocessing wastes (see Figure 2). Other reprocessing wastes include decontamination
solutions from maintenance and closure activities and second- and third-cycle reprocessing
extraction wastes. The decontamination solutions contain large quantities of sodium salts, and
since “other reprocessing waste” mainly consists of decontamination solutions, it is designated
“sodium-bearing waste” (SBW).
Beginning in 1963, INEEL began to stabilize the first-cycle and most of the second- and thirdcycle extraction wastes in a solid form through calcination. In addition to stabilization,
calcination resulted in reduction of waste volume. In 1978, the sodium-bearing wastes were
blended with calciner feed to help further reduce the inventory in the tank farm. In January
1990, the U.S. Environmental Protection Agency (EPA) issued a Notice of Noncompliance [1],
since the 1000 m3 (300,000 gallon) tanks did not meet the secondary containment requirements
of the Resource Conservation and Recovery Act. The Notice of Noncompliance resulted in a
Consent Order from the Idaho Department of Health and Welfare [2] that required INEEL to
upgrade the tank system or permanently cease use of all 1000 m3 (300,000 gallon) tanks
before the end of calendar year 2012. As of March 1998, INEEL completed calcination of the
first-cycle extraction waste and most of the second and third-cycle extraction waste. Small
heels (liquid and settled solids remaining in the bottom of the tank after emptying to the
maximum extent possible by using existing transfer equipment) remain in eight of the 1000 m3
(300,000 gallon) tanks. The tanks were also used to store additional SBW. Therefore, the
SBW consists of decontamination solutions from reprocessing activities, second- and thirdcycle reprocessing extraction wastes, contamination from first-cycle reprocessing extraction
wastes, settled solids in the tanks, and liquid wastes from ongoing and future maintenance and
closure activities at the INTEC (called newly generated liquid waste). DOE-ID continued to
calcine the SBW until May 2000, when the waste calcining facility at INEEL was placed on
standby as a result of the Consent Order.
1
FIGURE 1
2
Figure 1. INTEC area plot plan (not to scale).
FIGURE 2
3
Figure 2: Plan view of Tank Farm.
Incidental Waste/Waste Incidental to Reprocessing Criteria
Since 1969, the U.S. Nuclear Regulatory Commission (NRC) has recognized the concept of
incidental waste or waste incidental to reprocessing (WIR). Certain material that otherwise
would be classified as high-level radioactive waste (HLW) need not be disposed of as HLW and
sent to a geologic repository because the residual radioactive contamination after
decommissioning is sufficiently low as not to represent a hazard to the public health and safety.
Consequently, incidental waste is not considered HLW.
Incidental waste criteria were previously developed for management of certain wastes removed
from tanks at DOE’s Hanford site. These criteria were approved by the Commission in a Staff
Requirements Memorandum dated February 16, 1993, in response to SECY-92-391, “Denial of
PRM 60-4 - Petition for Rulemaking from the States of Washington and Oregon Regarding
Classification of Radioactive Waste at Hanford,” and are described in a letter from R.
Bernero/NRC, to J. Lytle/DOE, dated March 2, 1993 [3]. More recently, the criteria, as
modified, were included in the Final Policy Statement for the Decommissioning Criteria for the
West Valley Demonstration Project at the West Valley Site, dated February 1, 2002 [4]. In the
Policy Statement, the Commission noted the criteria that should be applied to the incidental
waste determinations at West Valley: (1) the waste should be processed (or should be further
processed) to remove key radionuclides to the maximum extent that is technically and
economically practical; and (2) the waste should be managed so that safety requirements
comparable to the performance objectives in 10 CFR Part 61, Subpart C, are satisfied.
On July 9, 1999, DOE issued DOE Order 435.1, “Radioactive Waste Management” [5]. The
DOE Order 435.1 and its associated manual and guidance [6,7] require that all DOE radioactive
waste be managed as HLW, transuranic (TRU) waste, or low-level radioactive waste (LLW).
The Order states that waste, determined to be incidental to reprocessing, is not HLW and shall
be managed in accordance with the requirements for TRU waste or LLW, if it meets appropriate
criteria. The Order discusses the WIR evaluation process, stating that incidental waste may be
managed as TRU waste if the wastes: “...(1) have been processed, or will be processed, to
remove key radionuclides to the maximum extent that is technically and economically practical;
and (2) will be incorporated in a solid physical form and meet alternative requirements for waste
classification and characteristics, as DOE may authorize; and (3) are managed pursuant to
DOE’s authority under the Atomic Energy Act of 1954, as amended, in accordance with the
provisions of Chapter III of this Manual [“Transuranic Waste Requirements”], as appropriate.”
Review Approach
DOE-ID and NRC developed a Memorandum of Understanding (MOU) [8] that establishes the
framework for NRC to provide technical assistance to DOE-ID in regard to the incidental waste
determinations. An Interagency Agreement [9] implements the MOU, which establishes that all
costs incurred by NRC, including contractor support, will be reimbursed by DOE-ID. In addition,
the MOU establishes that NRC’s activities under the MOU are carried out in an advisory
capacity, and that any advice given to DOE-ID under the MOU does not constitute regulatory
approval, authorization, or license for DOE activities.
The guidance document for DOE Order 435.1 recommends consultation with NRC for WIR
determinations. NRC’s review focused on Criterion 1, assessing whether the waste has been
4
processed, or will be processed, to remove key radionuclides to the maximum extent that is
technically and economically practical. NRC’s incidental waste guidance does not include a
TRU disposal option, and NRC staff considers it inappropriate to assess whether the TRU
disposal option provides safety equivalent to the performance objectives of 10 CFR Part 61,
since the Waste Isolation Pilot Plant (WIPP) is regulated by EPA and is outside of NRC’s
jurisdiction. Therefore, although the WIR determination addresses all three criteria in DOE
Order 435.1, NRC did not provide conclusions and recommendations for the TRU disposal
portion of the determination (Criteria 2 and 3). Rather, NRC only provided comments and
observations on the methodology for meeting Criteria 2 and 3, that were identified during
the review.
DOE-ID submitted the SBW WIR determination on September 25, 2001 [10,11]. After initial
review of the determination, NRC provided DOE-ID with a list of questions and comments in a
request for additional information (RAI) [12]. As a result of NRC observations and a change in
direction on the Idaho High-Level Waste and Facilities Disposition Environmental Impact
Statement (IHLW&FD EIS) [13], DOE-ID decided to revise its approach taken in the WIR
determination. DOE-ID responded to NRC’s RAI on January 29, 2002, providing the additional
information requested and summarizing the revised approach for the determination [14]. On
March 8, 2002, DOE-ID submitted the revised determination for NRC review [15, 16, 17, 18, 19,
and 20]. Unresolved or additional NRC concerns have been resolved through informal
communications with DOE-ID and/or are documented in the text of this report.
CRITERION ONE
The waste must have been processed, or will be processed, to remove key
radionuclides to the maximum extent that is technically and economically practical.
Original SBW WIR Determination (Draft A)
DOE-ID’s original SBW WIR determination focused on cesium (Cs)-137, strontium (Sr)-90,
technetium-99, and the transuranic radionuclides as key radionuclides, since they accounted for
99.96 percent of the initial INTEC spent fuel reprocessing radionuclide curie inventory [11].
Cs-137 and Sr-90 are the greatest contributors, alone accounting for 99.6 percent of the initial
curie inventory.
DOE-ID considered a number of options for treating SBW, including alternatives assessed in
the IHLW&FD EIS, recommendations from the National Research Council [21], and INTEC
evaluations. The original determination analyzed precipitation, ion exchange, and solvent
extraction methods to determine whether it was technically and economically practical to
remove additional key radionuclides from the SBW. Direct vitrification of SBW with disposal as
TRU waste at WIPP was used as the base case for economic evaluations of additional key
radionuclide removal options, since it was determined to be the most preferred of the
technically viable non-separations options by the DOE Decision Management Team (DMT) for
the IHLW&FD EIS.
One of the key arguments supporting the fulfillment of Criterion 1 was that the INTEC
segregated, removed, and converted the first-cycle extraction waste and most of the secondand third-cycle extraction waste (representing 98.3 percent of the key radionuclide inventory
5
from reprocessing) to a stable solid waste form (calcine), which will eventually be disposed of
as HLW. Additional removal of key radionuclides from the SBW would incur an additional $77
to $225 million and remove only 1.3 to 1.7 percent of the original reprocessing curies, resulting
in a cost of $129 to $290/curie above the cost of the baseline option (direct vitrification). DOEID determined that it was not economically practical to remove additional key radionuclides from
the SBW since their removal does not provide any additional protection to the public and the
environment.
After initial review of the SBW determination, NRC requested additional information on the
rationale for the DMT’s decision to use direct vitrification as the preferred alternative, rather
than one of the other waste form options (such as grouting, calcining, or steam reforming). It
was not clear to NRC that all the technically practical options had been evaluated in the context
of Criterion 1.
NRC also observed that the WIR determination process, laid out in DOE Order 435.1, should
allow flexibility in identifying the key radionuclides, so that a risk-informed approach could be
used to determine what radionuclides are “key” (i.e., the key radionuclides are those that
contribute most to risk and are the most significant for protection of public health and safety).
NRC also noted that Cs-137 and Sr-90 (and other relatively short-lived radionuclides) may
dominate occupational exposure, but it was not apparent that these radionuclides would be
significant contributors to expected future risks associated with WIPP.
In response to NRC’s observations, and based on a shift in direction for a preferred alternative
for SBW treatment in the development of the IHLW&FD EIS, DOE-ID decided to revise its
approach initially taken in the SBW WIR, and submitted a revised determination for NRC
review.
Revised SBW WIR Determination (Draft B)
The revised determination states that DOE Order 435.1 provides flexibility for each site to
identify key radionuclides as those that significantly impact disposal site performance
objectives. This allows DOE-ID to identify the key radionuclides considered for SBW treatment
and disposal and focus the technical and economic analysis on those radionuclides that are
important for meeting disposal performance objectives at WIPP. The performance objectives
require reasonable assurance that exposure to humans is within established limits. DOE-ID
determined that americium (Am)-241, plutonium (Pu)-238, Pu-239, and Pu-240 are the key
radionuclides, since they account for most of the calculated future risk in WIPP’s performance
assessment [22,23]. In addition, DOE-ID noted that 96 percent of the key radionuclides and 99
percent of all radionuclides generated from spent fuel reprocessing have been removed from
INTEC tank farm waste.
Because of the shift in DOE-ID’s assumptions while developing the IHLW&FD EIS, DOE-ID
decided to evaluate SBW treatment independent of calcine treatment, and in turn, no longer
assumed that a vitrification facility would be necessary at INEEL, as considered in the original
determination. Therefore, the revised determination presents a range of SBW direct
6
stabilization options as a base case (rather than choosing direct vitrification as the base case),
with an evaluation of the technical and economic practicality of additional key radionuclide
removal prior to disposal.
The revised determination treats SBW liquid and solids independently, by assuming (for all
options) that SBW solids are filtered from the process feed stream and treated separately.
Solids separation is a required process step for the contact-handled (CH) TRU grout and the
universal solvent extraction (UNEX) and TRU solvent extraction (TRUEX) separation options. It
may also be required for the other options, to improve process control and reduce final product
variability. The large quantity of heel solids recovered during tank closure operations may
require separate handling and additional treatment equipment. Therefore, there would still be
costs for solid handling, but it should be less than front-end filtration costs for the treatment
processes, so the cost estimates for calcination, steam reforming, and vitrification should be
conservative in the SBW WIR economic evaluation. The filtered solids (including those from
the tank heel removal) would be dried and packaged to meet WIPP waste acceptance criteria
(WAC) as remote-handled (RH) TRU waste.
DOE-ID’s economic evaluation (of direct stabilization options and options for removing
additional key radionuclides) only considers discriminatory costs, so the costs presented in the
WIR determination do not represent total costs and therefore, would not be used for life-cycle
budget planning. Discriminatory costs include costs to build and operate the facilities needed
for the specific treatment option, facility decontamination and demolition costs, interim storage
costs (for HLW storage needed for the additional key radionuclide removal options), and waste
disposal costs. Costs that were considered to be essentially the same for each alternative were
not incorporated in the cost analysis; such costs include utility costs, costs for facilities common
to all options, analytical support costs, management costs, maintenance costs, and the cost
of inflation.
Base Case
The revised approach uses direct stabilization as a base case, resulting in a TRU waste stream
that would be disposed of at WIPP and secondary waste streams that would be stabilized for
appropriate disposal. Characterization of the projected SBW forms is based on feasibility-level
studies for solidification processes and the SBW radionuclide inventory and mass balance. The
direct stabilization options considered in the determination were CH-TRU grout, calcination,
steam reforming, and direct vitrification. A brief description of each alternative, as well as its
cost estimate, follows.
CH-TRU Grout
For this option, SBW would be transferred to a surge storage tank using in-tank steam jets,
existing transfer piping, and new transfer piping that would be installed as part of this
alternative. The undissolved solids would be filtered from the waste, dried, and packaged for
disposal as RH-TRU waste at WIPP. The clarified liquid would then be passed through a fixed
bed ion-exchange system to remove cesium. The cesium-loaded ion-exchange resin,
estimated to be contaminated with TRU radionuclides in concentrations greater than 3700
becquerels (Bq) per gram (100 nanocuries per gram), would be treated and packaged for
disposal as RH-TRU waste at WIPP. The bulk liquid would be neutralized with calcium oxide,
7
and then combined with cement, fly-ash, blast furnace slag, and additional calcium oxide to
form a stable grout material that meets the WIPP waste acceptance criteria for CH-TRU waste.
The total project cost estimates for this option are based on the design and construction of a
new facility for treatment of the SBW; the estimate is $242 million (refer to Tables 1 and 2).
Other costs associated with this option are operating costs of $89 million, decontamination and
demolition costs of $67 million, CH-TRU disposal costs of $105 million [assuming 4600 m3
(1.6x105 cubic feet (ft3) of CH-TRU waste], and RH-TRU disposal costs of $63 million
[assuming 249 m3 (8790 ft3) of RH-TRU waste], for a total discriminatory cost estimate of
$566 million.
Table 1: SBW Treatment Alternative Costs
Direct Stabilization Alternatives
(Cost x millions)
Alternative
Total Project Cost
Operations
DD&D
Transportation & Disposal
Class-A Disposal at Hanford
Class-C Disposal at Hanford
CH-TRU Disposal at WIPP
RH TRU disposal at WIPP
HLW Disposal at National Rep.
Key-Radionuclide
Separation Alternatives
CH-TRU
Steam
Direct
Grout *
Calcination Reforming Vitrification UNEX* * TRUEX **
$242
$301
$485
$746
$989
$1,663
$89
$212
$163
$189
$416
$399
67
84
136
209
277
466
$15
$105
$63
Total
$0.1
$0.1
$0.3
$325
$270
$215
$87
$21
$14
$21
$143
$566
$922
$1,054
$1,359
$1,732
$2,779
*Includes up-front removal of Cs to allow disposal **Includes the cost of
as CH grout. (Total cost for grouting without Cs
vitrification & HLW
removal would be greater than $1 billion, including
disposal.
disposal costs for over 5,000 m3 of RH grouted
product.)
DD&D - decommissioning, decontamination, and demolition costs
8
Table 2: Waste Generation Quantities for SBW Disposal Options (dose rates in July 1999)
Solids
RH TRU
(m3)
RH TRU
(m3)
CH TRU
(m3)
CH-TRU grout
81
(130 R/hr)
168a
(251 R/hr)
4600
(190 mR/hr)
Calcination
81
(130 R/hr)
1,201
(46 R/hr)
50b
(<5 mR/hr)
Steam reforming
81
(130 R/hr)
981
(57 R/hr)
50b
(<5 mR/hr)
Direct vitrification
81
(130 R/hr)
764a
(35 R/hr)
110b
(<5 mR/hr)
Option
CH-Mixed
LLW
(m3)
RHMixed
LLW
(m3)
HLW (m3)
Direct stabilization
Separation of key
radionuclides
TRUEX
81
(130 R/hr)
UNEX
81
(130 R/hr)
6,763
(8 R/hr)
6,664
(93 mR/hr)
210
(36 R/hr)
20
(1,130 R/hr)
a. Volumes increased to meet shipping requirements.
b. Secondary waste streams.
Calcination with Maximum Achievable Control Technology Upgrade
This option involves upgrading the existing New Waste Calcining Facility (NWCF) with off-gas
treatment equipment, to comply with the Maximum Achievable Control Technology (MACT)
requirements for incinerators in 40 CFR Part 63.
After filtration of the solids, which will be packaged for disposal as RH-TRU waste at WIPP, the
filtered SBW liquid is blended with chemicals to prevent agglomeration during the calcination
process and fed to the calciner bed. In the calciner vessel, kerosene is combusted to
evaporate liquid in the SBW and produce a dry granular product (calcine). The calcine will be
packaged for disposal as RH-TRU waste at WIPP. The secondary wastes from the off-gas
treatment are expected to be disposed of as CH-LLW.
The cost estimate for this option is based on costs of constructing new facilities to house the
MACT control equipment and for managing calcined solids. The discriminatory cost for this
alternative is estimated at $922 million (refer to Tables 1 and 2).
9
Steam Reforming
This process is similar to the NWCF calciner in that both are fluidized bed devices. In this
process, the SBW is treated with additives and sent to a steam reforming system reactor,
where steam is used as the fluidizing gas and a refractory oxide material is used as the bed
media. Water in the waste is vaporized into superheated steam, while the nitrates are reduced
to nitrogen and oxygen. A fine solid inorganic salt is produced and packaged as RH-TRU
waste for disposal at WIPP. A secondary waste stream from off-gas treatment is expected to
be disposed of as Class C mixed LLW. In addition, an interim storage facility is needed to store
the waste, since the production rate of the stabilized waste exceeds the rate that it can be
removed and disposed of off-site.
The cost estimates are based on the design and construction of a new facility for treatment of
SBW. The estimate was based on the costs to construct the NWCF, which was considered to
be a similar facility. Additional costs were added for those features not considered in the
NWCF estimate (e.g., the remote operated waste packaging system, interim storage facility,
solids processing), based on cost estimates from other similar feasibility studies. The
estimated total discriminatory cost of this alternative is $1054 million (refer to Tables 1 and 2).
Direct Vitrification
This process begins with the solids filtration step, with solids disposal at WIPP as RH-TRU
waste. The clarified liquid is mixed with glass formers and various additives that will control the
reducing properties of the glass, aid in denitrification of the waste, and control glass viscosity.
This feed is injected into the melter as a slurry. First, the liquid is evaporated, then the solid
material is melted into a vitreous form. The glass is poured into storage canisters, transferred
to the interim storage facility, and ultimately disposed of at WIPP as RH-TRU waste. Gas and
vapors generated during the process are passed through the off-gas treatment system,
producing a secondary waste stream that is expected to be disposed of as Class C LLW. In
addition, an interim storage facility is needed to store the waste, since the production rate of the
waste exceeds the rate that it can be removed and disposed of off-site. The discriminatory cost
for this option is estimated at $1359 million (refer to Tables 1 and 2).
Waste Inventory and Characterization
The current inventory of SBW is a mixture that includes both liquid and solid components. The
solid portion is assumed to result from incomplete fuel dissolution, chemical precipitation
(formed during the unstable conditions caused when different waste types were added together
in the tanks), and decontamination activities. It is primarily present as settled tank heel solids
(in a fine particulate form), but can also be filtered from the liquid portion. The radiological
composition of the solids is similar to that of the liquid SBW, with all four key radionuclides
(Am-241, Pu-238, Pu-239, and Pu-240) occurring in both the solid and liquid portions.
However, the solids tend to have higher concentrations of radionuclides compared to
the liquids.
10
Technical Practicality of Further Key Radionuclide Removal
As noted above, the revised determination treats SBW liquid and solids independently, by
assuming (for all options) that SBW solids are filtered from the process feed stream and
treated separately.
Solids
Further dissolution of solids would be necessary to make chemical separation of key
radionuclides possible. However, since the solids have had long-term exposure to the SBW
liquid, which is $ 2 molar nitric acid solution, further dissolution would be difficult, if not
impossible. It is possible that strong acid mixtures at elevated temperatures could dissolve
some constituents in the SBW solids; however, no production-scale technologies exist, and
because of the relatively small solids quantity and the severe conditions anticipated for
dissolution, it was not technically practical to develop a dissolution process. Therefore, since no
technologies have been demonstrated for dissolving SBW solids, additional key radionuclide
removal is considered not technically practical.
Liquids
DOE-ID determined that it was technically possible to separate and remove additional key
radionuclides from SBW liquids using various precipitation and solvent extraction options.
The precipitation options considered by DOE-ID included hydroxide precipitation, modified
hydroxide precipitation, low-temperature precipitation, and high-temperature evaporation and
precipitation. All these options use either chemical or temperature manipulation to precipitate
metals and other constituents. These options were eliminated from further consideration (for
performing further key radionuclide separation and removal) because of technical difficulties
with maintaining an operational system under both normal and off-normal conditions.
Solvent extraction options were also considered as a method to remove additional key
radionuclides from the SBW, using various organic solvents. The two solvent extraction
methods considered were TRUEX and UNEX.
TRUEX removes actinides, including transuranics. The separation efficiency is 99.8 percent for
Pu and 99.9 percent for Am. The separated actinides are combined, concentrated by
evaporation, and vitrified for eventual disposal at the HLW geologic repository. Given the high
separation efficiencies, DOE-ID estimates that TRUEX could remove 100 TBq [3000 curies
(Ci)] of key radionuclides from the SBW liquid. The bulk waste from the process would be
concentrated by evaporation and grouted to produce an RH low-activity waste, expected to be
suitable for disposal as Class C LLW.
The UNEX process is very similar to the TRUEX process, and in addition, it removes Cs and Sr
isotopes. The separation efficiency for key radionuclides is greater than 99.9 percent for both
Pu and Am isotopes. The removal efficiency is 99.5 percent for Cs and 99.9 percent for Sr and
europium. Since the UNEX process also removes Cs and Sr, the bulk waste from the process
(after concentration and grouting) is expected to be suitable for Class A LLW disposal.
11
Economic Practicality of Further Key Radionuclide Removal
Only the methods of further key radionuclide removal that were considered technically practical
were retained for further economic evaluation. Therefore, DOE-ID’s economic evaluation
focused on costs for removing additional key radionuclides using the TRUEX and UNEX
processes. The economic practicality of removing additional key radionuclides from SBW liquid
was evaluated by determining removal costs and considering the effect of removing additional
key radionuclides on reducing radionuclide releases to the public at WIPP.
Costs of removing additional key radionuclides using TRUEX and UNEX
DOE-ID’s economic analysis of further key radionuclide removal presents the cost per curie for
additional key radionuclide removal. The high additional costs for these options (above that of
the direct stabilization options) are attributable to the construction and operation of facilities
needed to separate and treat the HLW fraction (key radionuclides removed) of the SBW. The
total project costs for TRUEX and UNEX processes are based on the design and construction
of a complex of new facilities at INTEC, which will include: a separations facility (for separating
key radionuclides using TRUEX and UNEX processes); a vitrification facility (to vitrify separated
key radionuclides for disposal at the HLW geologic repository); a low-activity waste treatment
building (to treat bulk waste from TRUEX and UNEX processes); an interim storage facility (to
store the HLW until a geologic repository is ready to accept it); and various small
support facilities.
The total discriminatory cost estimate for UNEX is $1732 million (refer to Tables 1 and 2). This
is $373 million to $1166 million above the cost of the direct stabilization options, or $124,000 to
$389,000 per curie for additional key radionuclide removal (given that UNEX is expected to
remove 3000 additional curies of key radionuclides).
The total discriminatory cost estimate for TRUEX is $2779 million (refer to Tables 1 and 2).
This is $1420 million to $2213 million above the cost of direct stabilization options, or $473,000
to $738,000 per curie of additional key radionuclide removal (given that TRUEX is expected to
remove 3000 additional curies of key radionuclides).
Effect of Further Key Radionuclide Removal on WIPP Repository Performance
The WIPP Land Withdrawal Act (LWA) provides capacity limits based on radiation doses for
CH and RH TRU. The quantity of waste for some of the SBW treatment options may exceed
the limit for $100 roentgens per hour (R/hr) RH waste. DOE-ID notes that the waste will be
treated to meet the WAC of <100 R/hr, so as not to exceed the bounds of the LWA.
The WIPP Compliance Certification Application and supporting performance assessment
modeled TRU components from all waste planned for disposal. The performance assessment
for WIPP estimates that the source term of key radionuclides is 1.51x105 TBq (4,070,000 Ci)
from all sources at closure [22,23]. The key radionuclide (Am-241, Pu-238, Pu-239, and
Pu-240) source term from the SBW is estimated at 170 TBq (4500 Ci). It is estimated that the
UNEX and TRUEX processes could remove an additional 100 TBq (3000 Ci) of key
radionuclides from the SBW liquid, which is less than 0.1 percent of the total WIPP curies at
closure. Since the large additional cost to remove 100 TBq (3000 Ci) of key radionuclides
12
would not result in a significant reduction of the radionuclide inventory at WIPP, DOE-ID
determined that it was not economically practical to remove additional key radionuclides from
the SBW.
NRC REVIEW AND CONCLUSIONS
The following assumptions were made in assessing conformance with Criterion 1:
•
NRC staff is providing technical assistance, only. NRC is not a regulatory authority for
SBW stabilization and disposal.
•
NRC staff focused its review on Criterion 1. Any comments made with regard to Criteria 2
and 3 were observed during the Criterion 1 review, and do not indicate a thorough review
of Criteria 2 and 3.
•
Cost estimates associated with the different options are reasonable.
•
Identifying key radionuclides based on predicted performance is reasonable.
•
The characterization of the radionuclide composition of the SBW liquids and solids is a
reasonable representation of the actual composition.
The following conclusions are made with respect to Criterion 1:
•
NRC staff agrees that it is not technically practical to remove additional key radionuclides
from the SBW solids prior to disposal.
•
NRC staff agrees that even though the technology exists to remove additional key
radionuclides from SBW liquid, it is not economically practical, since removing additional
key radionuclides for disposal at a HLW geologic repository would not significantly reduce
the radionuclide inventory at WIPP.
The following recommendations are noted with respect to meeting Criterion 1:
•
Although a significant amount of work has been completed in an attempt to develop the
SBW liquid and solid radionuclide concentrations, limited information is available in some
key areas or to support some key assumptions. The residual uncertainty can likely be
reduced through the collection of additional information during future activities (e.g., solid
and liquid sampling). For the SBW WIR determination, the residual uncertainty is not
expected to be significant enough to invalidate DOE-ID’s conclusion that SBW is WIR, and
therefore, can be managed as TRU waste. As additional information is collected, an
impact assessment on the SBW WIR determination should be completed and any
significant impacts communicated to NRC.
13
•
NRC’s RAI requested DOE-ID to provide a brief analysis describing impacts to workers
resulting from the options evaluated. In the response to the RAI, DOE-ID noted that dose
to the workers was generally found to be insignificant, and that allowable worker radiation
exposures are set by DOE regulations. Additional shielding was added to facilities (that
would be required for the various SBW treatment options) that handle more highly
radioactive waste, so that the worker exposure is projected to be about the same for all
options. Likewise, shipping, handling, and disposal facilities all have equipment and
procedures to handle waste product safely. Therefore, increased radiation levels for
various waste types were reflected in increased costs for additional shielding, shipping,
and handling requirements. DOE-ID noted that this discussion would be included in the
revised SBW WIR determination; however it appears that it was not included. DOE-ID
should provide this discussion in the final WIR determination.
Although NRC staff review of the SBW WIR determination focused on Criterion 1, the staff also
noted the following during its review:
•
DOE-ID noted that WIPP is currently not permitted to accept RH-TRU waste, but it is
expected to be permitted in 2003. DOE-ID also noted that the draft WAC for RH-TRU are
not expected to change. NRC staff suggests that if there are changes to the plans to
permit WIPP to accept RH-TRU waste or if the draft WAC for RH-TRU change, DOE-ID
should revisit the WIR determination before final decisions regarding the SBW treatment
process and final waste forms are made.
•
The residual uncertainty regarding the radionuclide inventory is expected to have a greater
impact on DOE-ID’s WIR determination for tank closure. NRC plans to document its
concerns regarding the current tank inventories in a future RAI on the tank closure
WIR determination.
•
NRC supports DOE-ID using the most economically efficient technology that will result in
waste that meets the WIPP WAC.
14
REFERENCES
1.
United States Environmental Protection Agency Notice of Noncompliance in the Matter of
the United States Department of Energy Idaho Operations Office, January 29, 1990.
2.
Idaho Department of Health and Welfare Consent Order in the Matter of United States
Department of Energy, Idaho National Engineering Laboratory, Idaho Code § 39-4413,
dated April 3, 1992, modifications dated March 17, 1994, August 18, 1998, and April 20,
1999.
3.
Letter from R. Bernero/NRC, to J. Lytle/DOE, March 2, 1993.
4.
U.S. Nuclear Regulatory Commission, “Decommissioning Criteria for the West Valley
Demonstration Project (M-32) at the West Valley Site; Final Policy Statement,”
67 FR 5003, February 1, 2002.
5.
U.S. Department of Energy, “DOE Order 435.1: Radioactive Waste Management,”
July 9, 1999.
6.
U.S. Department of Energy, “DOE Manual 435.1-1: Radioactive Waste Management
Manual,” July 9, 1999.
7.
U.S. Department of Energy, “DOE Guide 435.1-1: Implementation Guide for Use with DOE
M 435.1-1,” July 9, 1999.
8.
“Memorandum of Understanding Between the U.S. Department of Energy and the U.S.
Nuclear Regulatory Commission Regarding the Management of (1) Existing SodiumBearing Waste and (2) Residual Waste from the Closure of the High-Level Waste Storage
Tanks at the Idaho National Engineering and Environmental Laboratory,” No. DE-GM0701ID11435, September 7, 2001.
9.
“Department of Energy Funds-Out Interagency Agreement,” No. DE-AI07-01ID14188,
September 6, 2001.
10. Letter from J.T. Case/DOE-ID to J.T. Greeves/NRC, “Request for NRC Review of Idaho
National Engineering and Environmental Laboratory Waste Incidental to Reprocessing
Determination for Sodium-Bearing Waste (INTEC-WP-01-052),” September 25, 2001.
11. U.S. Department of Energy, Idaho Operations Office, “Idaho Nuclear Technology and
Engineering Center Sodium-Bearing Waste -- Waste-Incidental-to-Reprocessing
Determination Report, Draft A,” DOE/ID-10780, August 2001 (and associated documents).
12. Letter from C.E. Abrams/NRC to J.T. Case/DOE-ID, “Request for Additional Information on
the Idaho National Engineering and Environmental Laboratory Draft Waste Incidental to
Reprocessing Determination for Sodium-Bearing Waste (INTEC-WP-01-052),”
December 12, 2001.
13. U.S. Department of Energy, “Idaho High-Level Waste and Facilities Disposition Final
Environmental Impact Statement,” DOE/EIS-0287, Date to be determined.
15
14. Letter from J. Case/DOE-ID to C.E. Abrams/NRC, “Responses to the Request for
Additional Information on the Idaho National Engineering and Environmental Laboratory
Draft Waste Incidental to Reprocessing Determination for Sodium-Bearing Waste
(INTEC-WP-02-004),” January 29, 2002.
15. Letter from J. Case/DOE-ID to J.T. Greeves/NRC, “Revised Draft Waste Incidental to
Reprocessing Determination Report for Idaho National Engineering and Environmental
Laboratory (INEEL) Sodium-Bearing Waste (INTEC-WP-02-012),” March 8, 2002.
16. U.S. Department of Energy, Idaho Operations Office, “Idaho Nuclear Technology and
Engineering Center Sodium-Bearing Waste -- Waste-Incidental-to-Reprocessing
Determination Report, Draft B,” DOE/ID-10780, March 2002.
17. U.S. Department of Energy, Idaho Operations Office, “Engineering Design File -Supporting Cost Data for the SBW Waste Incidental to Reprocessing Evaluation,”
EDF-SBW-WIR-001, March 5, 2002.
18. Sandia National Laboratories Waste Isolation Pilot Plant -- RH-TRU Impact Assessment
with PAVT Baseline (RHVT), dated November 24, 2000.
19. U.S. Department of Energy, Idaho Operations Office, “Engineering Design File -Validation of Radionuclide Mass Balance Used in the INTEC SBW WIR Determination
Report,” EDF-1920/INEEL/EXT-2001-534, Revision 3, March 18, 2002.
20. U.S. Department of Energy, Idaho Operations Office, “Engineering Design File -Comparison of Candidate Waste Streams to WIPP Waste Acceptance Criteria,”
EDF-1984, Revision 0, March 19, 2002.
21. National Research Council, “Alternative High-Level Waste Treatments at the Idaho
National Engineering and Environmental Laboratory,” National Academy of
Sciences, 1999.
22. U.S. Department of Energy, “Waste Isolation Pilot Plant Compliance Certification
Application,” October 29, 1996.
23. Hadgu, T. and Ross Kirkes, “Sandia National Laboratories Carlsbad Programs Group
Waste Isolation Pilot Plant RH-TRU Inventory Impact Assessment Report,” June 2001.
16
LIST OF ABBREVIATIONS AND ACRONYMS
Am
americium
CFR
Code of Federal Regulations
CH
contact-handled
Cs
cesium
DD&D
decommissioning, decontamination, and demolition costs
DOE
U.S. Department of Energy
DMT
Decision Management Team
EPA
U.S. Environmental Protection Agency
HLW
high-level radioactive waste
ID
Idaho Operations Office
IHLW&FD EIS
Idaho High-Level Waste and Facilities Disposition Environmental Impact
INEEL
Statement
Idaho National Engineering and Environmental Laboratory
INTEC
Idaho Nuclear Technology and Engineering Center
LLW
low-level radioactive waste
LWA
WIPP Land Withdrawal Act
MACT
maximum achievable control technology
MOU
Memorandum of Understanding
NRC
U.S. Nuclear Regulatory Commission
NWCF
New Waste Calcining Facility
Pu
plutonium
R/hr
roentgen per hour
RAI
request for additional information
RH
remote-handled
SBW
sodium-bearing waste
Sr
strontium
TRU
transuranic
TRUEX
transuranic solvent extraction
UNEX
universal solvent extraction
WAC
waste acceptance criteria
WIPP
Waste Isolation Pilot Plant
WIR
waste incidental to reprocessing
17