Disposition of Fast Critical Assembly Plutonium, 13359-13360 [2021-04707]

Agencies

• DEPARTMENT OF ENERGY
• National Nuclear Security Administration

[Federal Register Volume 86, Number 43 (Monday, March 8, 2021)]
[Notices]
[Pages 13359-13360]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-04707]



[[Page 13359]]

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DEPARTMENT OF ENERGY

National Nuclear Security Administration


Disposition of Fast Critical Assembly Plutonium

AGENCY: National Nuclear Security Administration, Department of Energy.

ACTION: Amended record of decision.

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SUMMARY: The National Nuclear Security Administration (NNSA), a semi-
autonomous agency within the Department of Energy (DOE), is amending 
its prior decision to disposition up to 350 kilograms (kg) of foreign 
Gap Material Plutonium from preparation for emplacement in the Waste 
Isolation Pilot Plant (WIPP) to disposition using an electrolytic 
dissolver in H-Canyon, vitrification with high level radioactive waste 
(HLW) at the Defense Waste Processing Facility (DWPF), and storage at 
Savannah River Site (SRS) until a geologic repository is available. 
NNSA has determined through feasibility and process technology studies 
that this disposition path could be performed at a substantially lower 
cost than preparation for disposal at WIPP. NNSA has prepared a 
Supplement Analysis (SA) to inform this amended decision and has 
determined that no additional National Environmental Policy Act (NEPA) 
review is necessary.

FOR FURTHER INFORMATION CONTACT: For further information on this 
Amended Record of Decision (ROD) or the Fast Critical Assembly (FCA) 
SA, or to receive related NEPA documents, please contact: Ms. Amy 
Miller, NEPA Compliance Officer, National Nuclear Security 
Administration, Office of General Counsel, (505) 845-5090; or by email 
to [email protected]. This Amended ROD and the FCA SA (DOE/EIS-
0283-S2-SA-02, Supplement Analysis for the Disposition of Fast Critical 
Assembly Plutonium, January 2021) will be available on the internet at 
https://energy.gov/nepa. For further information on FCA disposition, 
contact Ms. Lisa McGuire, Office of Material Management and 
Minimization, National Nuclear Security Administration, (803) 952-6921 
or email at [email protected].

SUPPLEMENTARY INFORMATION:

Background

    In the Surplus Plutonium Disposition Supplemental Environmental 
Impact Statement (SPD Supplemental EIS) (DOE/EIS-0283-S2, April 2015), 
NNSA evaluated disposition options for 13.1 metric tons (MT) of surplus 
plutonium consisting of 6 MT of non-pit material and 7.1 MT of pit 
material. The 6 MT of surplus non-pit plutonium included 0.9 MT (900 
kg) of excess capacity to allow for the possibility that the NNSA might 
identify additional quantities of surplus plutonium that could be 
processed for disposition using the facilities and capabilities 
analyzed in the SPD Supplemental EIS.
    NNSA assessed the impacts of shipment, receipt, treatment, storage, 
and disposition of up to 900 kilograms (kg) of foreign Gap Material 
Plutonium, of which the FCA fuel is a subset, in an Environmental 
Assessment (EA) for Gap Material Plutonium--Transport, Receipt, and 
Processing (DOE/EA-2024, December 2015), with a subsequent Finding of 
No Significant Impact (FONSI). In the 2015 EA, NNSA noted that up to 
375 kg of the Gap Material Plutonium may require stabilization prior to 
disposition. NNSA further stated that interim storage and disposition 
of the Gap Material Plutonium would be in accordance with decisions 
made for disposition of U.S. surplus plutonium in the SPD Supplemental 
EIS.
    In a 2016 ROD (81 FR 19588, April 5, 2016), NNSA announced its 
decision to implement the preferred alternative, the Waste Isolation 
Pilot Plant (WIPP) (Dilute and Dispose) Alternative, for disposition of 
6 MT of surplus, weapons-usable, non-pit plutonium. In the 2016 ROD, 
NNSA refers specifically to the 2015 Gap Material Plutonium EA. In the 
SPD Supplemental EIS, NNSA evaluated five alternatives for disposition 
of 6 MT of plutonium, which includes the 900 kg of Gap Material 
Plutonium, including the H-Canyon/HB-Line to DWPF Alternative and WIPP 
(Dilute and Dispose) Alternative.
    Based on an international agreement, the Japan Atomic Energy Agency 
(JAEA) is providing funding to NNSA to disposition the FCA plutonium 
(FCA fuel), a subset of the Gap Material Plutonium. The United States 
received the FCA fuel from Japan for nonproliferation purposes to 
disposition it safely and securely, and it is currently stored at SRS 
awaiting further processing for final disposition.
    The FCA fuel is different from the rest of the 6 MT because it is 
clad in stainless steel, whereas the majority of the 6 MT is not clad 
in stainless steel. The stainless-steel cladding must be removed prior 
to processing the plutonium. As described in the 2015 Gap Material 
Plutonium EA, NNSA intended to separate the FCA fuel from its 
stainless-steel cladding and convert it to an oxide form \1\ for 
dilution at SRS to meet the waste acceptance criteria for disposal at 
WIPP near Carlsbad, New Mexico. Because of the high cost to install and 
operate a decladding and oxide conversion process, NNSA initiated an 
evaluation of alternative processing technologies. Based on these 
feasibility and process technology studies, NNSA determined that 
electrolytic dissolution could be performed at SRS at a substantially 
lower cost than the mechanical decladding and oxidation process.
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    \1\ The majority of FCA fuel is stainless-steel clad alloy and 
requires conversion to an oxide prior to dilution. A small portion 
of the FCA fuel is stainless-steel clad oxide and, therefore, would 
not require conversion prior to dilution. This AROD applies to both 
the stainless-steel clad alloy and the stainless-steel clad oxide.
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    Based on results of studies and experiments conducted by Savannah 
River Nuclear Solutions in 2017 and 2018, NNSA is changing the 
disposition path for up to 350 kg of FCA fuel. Instead of using the 
WIPP Alternative, NNSA will employ the H-Canyon/HB-Line Alternative, 
using a dissolver in H-Canyon, vitrification with HLW at the Defense 
Waste Processing Facility (DWPF), and storage at SRS until a geologic 
repository is available, as described in the SPD Supplemental EIS. 
However, NNSA will use an electrolytic dissolver rather than a chemical 
dissolver in H-Canyon to dissolve the FCA fuel to prepare it for 
transfer to DWPF.

Disposition Process

    The material will be dissolved using an electrolytic dissolver in 
H-Canyon. The DOE Office of Environmental Management (DOE/EM) 
categorically excluded replacement of a failed electrolytic dissolution 
unit in H-Canyon with a spare electrolytic dissolution unit. (OBU-H-
2019-0006, January 14, 2019, available at https://www.energy.gov/nepa/downloads/cx-019585-electrolytic-dissolution-fast-critical-assembly-material).
    The FCA fuel will be transported to H-Canyon where containers of 
the FCA fuel will be removed from the shipping packages and placed in 
or attached to a charging device for transport to the dissolver. After 
preparing the electrolytic dissolver with a cold chemical solution of 
nitric acid, the cans will be charged to (placed in) the dissolver. 
Electrical power will be applied to the dissolver resulting in the 
dissolution of the FCA cladding and fuel. The only difference between 
the H-Canyon process used to dissolve the FCA fuel with an electrolytic 
dissolver rather than a chemical dissolver is the

[[Page 13360]]

application of the electrical current. NNSA estimates that dissolution 
will be complete in less than 24 hours per charge. After each 
dissolution cycle is complete, solution samples will be obtained to 
ensure complete dissolution of the FCA fuel. If necessary, a subsequent 
heating step will be performed to complete the dissolution process. 
NNSA estimates that 18 batches would be required to complete processing 
of the FCA fuel. After completion of each batch, the material will be 
transferred to an accountability tank in H-Canyon and then to a canyon 
vessel for storage and eventual transfer to the H-Tank Farm. 
Immobilization and storage of the material will occur at DWPF pending 
disposal in a geologic repository. NNSA estimates that vitrification of 
the FCA fuel along with HLW at DWPF will result in three waste 
canisters.
    The electrolytic dissolution process is very similar to the 
chemical dissolution process as described in Appendix B, section B.1.3, 
of the SPD Supplemental EIS. Dissolved FCA fuel solutions will be very 
similar to those resulting from chemical dissolution, and compatible 
with transfer to the H-Area Tank Farm pending immobilization in DWPF. 
FCA dissolution operations would be scheduled in conjunction with other 
H-Canyon operations and coordinated with tank farm and DWPF operations.
    In the SPD Supplemental EIS, NNSA evaluated disposition of 6 MT of 
plutonium using both the H-Canyon/HB-Line to DWPF Alternative and the 
WIPP Alternative. The impact assessment of both alternatives includes 
up to 350 kg of FCA fuel. In the Supplement Analysis for Disposition of 
FCA Plutonium, NNSA compared the impacts of processing 350 kg of FCA 
fuel using both alternatives.
    Differences in doses and potential latent cancer fatalities to 
workers and the public between the WIPP Alternative and the H-Canyon/
HB-Line Alternative are minor. In the case of electrolytic dissolution, 
worker dose would be lower than the H-Canyon/HB-Line chemical 
dissolution and WIPP alternatives. Both would require handling and de-
cladding of the fuel prior to processing. In the SPD Supplemental EIS 
(Tables 4-3 and 4-4), NNSA estimated radiation doses and impacts, in 
terms of latent cancer fatalities (LCFs), from operations for the H-
Canyon/HB-Line Alternative (including the material evaluated in the SA) 
to workers and the public. Worker doses were estimated to be less than 
the SRS administrative limit of 500 millirem (mrem) per year, resulting 
in no LCFs on an annual basis. Over the life of the H-Canyon/HB-Line to 
DWPF Alternative (13 years), NNSA estimated that operations could 
result in an estimated 2 LCFs to involved workers and none to members 
of the public or the maximally exposed individual. The proposed action 
was included in the estimates for the H-Canyon/HB-Line Alternative. No 
LCFs in addition to those NNSA previously estimated would result from 
implementation of the proposed action.
    Vitrification of the FCA fuel in DWPF would result in an estimated 
three HLW glass canisters. Less CH-TRU waste would be generated using 
the H-Canyon/HB-Line Alternative because WIPP alternative processing 
results in TRU waste for disposal at WIPP. Other differences in waste 
generation are minor.
    To ensure safe and secure operations, NNSA, in conjunction with 
DOE/EM, which owns the facilities, would review and revise, as needed, 
safety basis documents for all involved facilities at SRS.

Basis for Decision

    To disposition the FCA fuel the H-Canyon/HB-Line Alternative can be 
implemented at a substantially lower cost than the WIPP Alternative. 
The SRS H-Canyon has used electrolytic dissolution in the past. The 
process is well known and can be implemented with little technology 
maturation. The impacts from activities related to the disposition of 
FCA fuel have been evaluated in the SPD Supplemental EIS. There are no 
substantial differences in environmental impacts between using the 
electrolytic dissolver and the standard H-Canyon dissolver for this 
amount of material (up to 350 kg). All processes downstream of the 
dissolver are the same as those analyzed in the H-Canyon/HB-Line to 
DWPF Alternative. The FCA fuel would be prepared for disposition and 
safely stored at SRS in existing facilities pending the availability of 
a geologic repository.

Amended Decision

    NNSA has decided to change the disposition pathway for up to 350 kg 
FCA fuel from the WIPP Disposal Alternative to the H-Canyon/HB-Line to 
DWPF Alternative, as described and evaluated in the SPD Supplemental 
EIS. NNSA will use electrolytic dissolution instead of chemical 
dissolution because the FCA fuel is clad in stainless steel.
    FCA fuel comprises less than half of the 0.9 MT of gap material 
plutonium evaluated in DOE/EA-2024, and less than 6 percent of the 6 MT 
NNSA decided to disposition using the WIPP Disposal Alternative. NNSA 
remains committed to dispositioning 6 MT of surplus plutonium using the 
WIPP Disposal Alternative, as NNSA previously decided (81 FR 19588, 
April 5, 2016).

Signing Authority

    This document of the Department of Energy was signed on March 1, 
2021, by Charles P. Verdon, Acting Under Secretary for Nuclear Security 
and Administrator, NNSA, pursuant to delegated authority from the 
Secretary of Energy. That document with the original signature and date 
is maintained by DOE. For administrative purposes only, and in 
compliance with requirements of the Office of the Federal Register, the 
undersigned DOE Federal Register Liaison Officer has been authorized to 
sign and submit the document in electronic format for publication, as 
an official document of the Department of Energy. This administrative 
process in no way alters the legal effect of this document upon 
publication in the Federal Register.

    Signed in Washington, DC, on March 3, 2021.
Treena V. Garrett,
Federal Register Liaison Officer, U.S. Department of Energy.
[FR Doc. 2021-04707 Filed 3-5-21; 8:45 am]
BILLING CODE 6450-01-P