Wednesday, August 22, 2012

MOX Mysteries: Better to Bury than to Burn?

Tuesday, August 21, 2012 / Conference Room, Holiday Inn Express, 60 Entrada Dr, Los Alamos, NM:

The public was invited to meet with DOE officials in order to learn about the latest developments in the ongoing planning for the disposition of US surplus plutonium. This public hearing, or informational, was a part of the National Environmental Policy Act (NEPA) process, mandated by Congress as a way to involve the public in the planning for large projects sponsored and funded by the federal government.

5:30PM - 6:30PM / A set of ~6 posters, each attended by 1 or 2 DOE experts, were made available to inform the public about aspects of this program. Written handouts included DOE's "Summary of the Draft Plutonium Disposition Supplemental Environmental Impact Statement," a 59 page document, and a collection of viewgraphs summarizing the talk to be given by the NEPA Document Manager.

6:30PM - 7:00PM / NEPA Document Manager Sachiko McAlhany gave a talk updating the government's program. No questions from the public were entertained by Ms. McAlhany, nor by any of the other DOE officials present in the room.

7:00 - 7:30PM / Members of the public were allotted 5 minutes each to present oral remarks about the program. The DOE officer-in-charge stated that no immediate DOE response to these remarks would be forthcoming.

The US government's approach to disposing of surplus plutonium (Pu) is interesting for at least two reasons. First, the amount of plutonium involved in the program is large, 61.5 metric tons (MT) over all, at present; which may increase in the future. This surplus is mostly Pu obtained from the decommissioning and disassembly of US nuclear weapons (41.1 MT); i.e., several thousand nuclear warheads which, in order to fulfill an agreement* with the Russians, must be removed from the nuclear weapons stockpile and destroyed. Second, the process of destruction must take place in such a way that it would be impossible at some future time to retrieve the Pu, and to reconstitute the warheads.

Initially, the US had wanted to blend the Pu with other highly radioactive materials, to encase the mixture in glass filled canisters, and to bury the canisters at some remote site. However, the Russians objected to this plan because, they claimed, it would be possible eventually to retrieve and purify the Pu from these canisters. Instead, the Russians argued that the Pu should be formed into reactor fuel rods, and burned in power generating nuclear reactors. It appears that the US has come to agree with the Russian point-of-view, and that the present DOE program reflects this latest belief.

*(In the "US-Russia Plutonium Management and Disposition Agreement of 2000", each government promised to destroy 34 MT of Pu from nuclear warheads. In 2010, another 7.1 MT of Pu from nuclear warheads was assigned for destruction by each side. In the future, still more Pu may be made available from retired nuclear weapons.)

In order to take Pu from nuclear weapons and turn it into so-called Mixed Oxide (MOX) fuel, to be burned in commercial nuclear reactors, two essential steps are required: 1) Pu metal must be extracted from nuclear warheads and the metal transformed physically and chemically into plutonium oxide powder. 2) The powder must be processed, formed, and combined with other metals, principally uranium, into MOX fuel rods. Both of these steps require specially designed facilities, containing specialized tools, and must be performed while observing the strictest security safeguards.

Whereas it is now planned that step #2 will be performed at the DOE's Savannah River Site (SRS), there are two alternative locations still being considered for step #1; viz., Los Alamos National Laboratory (LANL) and SRS.

Naturally, local citizenry in Santa Fe, NM are exercised by the idea of bringing more Pu to LANL, and tby the possibility of expanding the LANL's nuclear weapons mission. Most of the oral remarks presented by the public tonight reflected some part of this concern. However, one member of the public, identifying himself as a chemist currently working at LANL, opined that LANL's present plutonium facility (PF-4) was fully able to cope with the workload described in the DOE's plan to disposition surplus plutonium from decommissioned nuclear warheads. He said that he believed that the destruction of surplus PU by burning in nuclear reactors was much preferable to its disposition by blending, vitrification, and burial since the vitrified material could eventually be retrieved and reconstituted.

For more info, see my blogpost of February 4, 2012.

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