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safety performance cleanup closure M E Environmental Management Sodium-Bonded Spent Nuclear Fuel Discussion for the National Spent Nuclear Fuel Program Office of Nuclear Materials Disposition Meeting Debbie Kula Office of Nuclear Materials Disposition April 15, 2009
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safety performance cleanup closure M E Environmental Management 2 Challenge The Department is currently responsible for the safe and efficient management of ~57 MTHM of Na- bonded SNF: –EM: ~0.25 MTHM FFTF fuel (driver) 34 MTHM Fermi-1 fuel (blanket) –NE:~22 MTHM fuel from the EBR-II (~20 MTHM blanket, ~2 MTHM driver) –NNSA: ~0.05 MTHM Na-bonded-debris-bed fuel capsules from SNL –All has been consolidated at INL
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safety performance cleanup closure M E Environmental Management 3 Challenge, continued WASRD: national repository will only accept HLW and/or SNF that is not subject to regulation as hazardous waste under RCRA. Na-bonded SNF contains metallic sodium and could be considered a characteristic reactive waste under RCRA. Either remove the Na or demonstrate the amount present is not reactive and will not negatively impact the repository. If no national repository, may need to assess impact of Na on long-term storage.
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safety performance cleanup closure M E Environmental Management 4 Historic documents: September 2000 ROD for the Treatment & Management of Sodium-Bonded Spent Nuclear Fuel (DOE/EIS-0306) –Decision to use EMT (Electrometallurgical Treatment) to treat the EBR-II SNF and “miscellaneous small lots” of Na- bonded SNF (FFTF fuel and the SNL Na-bonded-debris- bed fuel capsules). –The Fermi-1 Na-bonded SNF will continue to be stored while alternative treatments are evaluated. If no alternative proves more cost effective, EMT remains an option.
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safety performance cleanup closure M E Environmental Management 5 Historic documents, continued March 2006 Report to Congress –Preferred Alternative is to: Process EBR-II blanket and driver by EMT Direct dispose Fermi-1 blanket and FFTF if not RCRA regulated Otherwise use MEDEC (Melt-Drain-Evaporate- Carbonate process ) or alcohol wash for Fermi-1 blanket and EMT for FFTF
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safety performance cleanup closure M E Environmental Management 6 Historic documents, continued 2007 INL Preferred Disposition Plan for Sodium- Bonded SNF –Recommends: Treating the EBR-II driver and blanket and Na-bonded FFTF using EMT Notes MEDEC for the EBR-II blanket does not offer any significant advantages Fermi-1 fuel should be treated by MEDEC if it cannot be direct disposed
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safety performance cleanup closure M E Environmental Management 7 Current Activities NE currently treating small amounts of EBR-II fuel by EMT under AFCI. ARRA (American Recovery and Reinvestment Act) funds to move some of the EBR-II fuel from the 666 basin to MFC. No additional funding to treat this fuel. The Na-bonded FFTF fuels at Hanford were shipped to MFC. Funding for treatment of this fuel is still uncertain. The two fuels are similar in composition and form and could be processed together.
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safety performance cleanup closure M E Environmental Management 8 EM’s Objective Determine optimum solution for management (storage/treatment/disposal) of Na-bonded SNF –Although there is a 2000 ROD and subsequent studies, there is no concrete, integrated plan for all the Department’s Na- bonded SNF –Need to assess what should be done with this fuel Is 2000 ROD still the answer? Continue EMT? Who pays for what? Determine RCRA applicability to Fermi-1 blanket? Other technologies? Plan for potential long term storage?
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safety performance cleanup closure M E Environmental Management 9 Next steps Convene working group to develop a concrete, integrated path forward –Short term (through this CY): Analyze options and recommend near-term activities Elevate issues to management for decision –Longer-term: Develop appropriate strategies to support revised Departmental policy based on proposed Blue Ribbon Panel
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safety performance cleanup closure M E Environmental Management Background info
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safety performance cleanup closure M E Environmental Management 11 Driver vs. Blanket Driver fuel swells when irradiated. The metallic sodium enters the metallic fuel and becomes inseparable. Separation requires dissolution or melting. Blanket fuel does not swell to the same degree so there is no inter-diffusion between fuel and cladding. Mechanical stripping is possible.
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safety performance cleanup closure M E Environmental Management 12 Treatment Technologies EMT (aka Electrochemical Treatment) Direct Disposal –Two steps: (1) demonstrate the amount present is not reactive and (2) demonstrate it will not negatively impact the repository. MEDEC (Melt-Drain-Evaporate-Carbonate): –First developed in 1980’s to remove sodium from non-irradiated EBR- II fuel. –Uses a combination of heat and reduced pressure to melt and vaporize bonded sodium, removing it from the metal fuel. –MEDEC tests showed the process is viable. –Additional evaluations are needed to demonstrate the waste form would be acceptable in the repository.
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safety performance cleanup closure M E Environmental Management 13 Treatment Technologies, continued Alcohol wash –Used by Rocketdyne in mid-80’s to remove sodium from 17 MTHM of spent EBR-II blanket fuel. –Fuel element cladding is cut to expose fuel slugs, which are then soaked twice in an alcohol bath containing 20% water. Alcohol wash is solidified as sodium carbonate and disposed as LLW. –Historic documents have suggested this technology is due further evaluation.
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safety performance cleanup closure M E Environmental Management 14 Other Treatment Technologies GMODS (Glass Material Oxidation and Dissolution System): –Combine unprocessed Na-bonded SNF and lead-borate glass in a glass melter at very high temperature. The U and Pu in the SNF would be converted into oxides and dissolved in the glass. –Waste form is borosilicate glass and would contain uranium, the transuranic elements, the fission products and the Na. Direct Plasma Arc Vitreous Ceramic Process –The Na-bonded SNF would be cut into small pieces, melted and oxidized in a rotating furnace containing molten ceramic materials at extremely high temperatures. A direct current plasma torch would supply the energy required
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safety performance cleanup closure M E Environmental Management 15 Other Treatment Technologies, continued Both GMODS and Plasma Arc technologies dismissed because they were not as mature as EMT and would require new construction and large equipment, new hot cells.
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