The Obama administration's fiscal year 2010 budget request includes funds to increase production capacity for tritium, a radioactive gas used to boost the explosive power of U.S. nuclear weapons, even as the U.S. government is taking steps to scale back the amount of tritium it produces.
Part of the reason is that the plans for tritium production have to be put in place more than a year ahead of time, officials from the Department of Energy's National Nuclear Security Administration (NNSA), which is responsible for tritium production, said in interviews last month. Because tritium decays relatively rapidly, supplies of it have to be replenished periodically to maintain a nuclear arsenal of a given size.
The tritium for the U.S. arsenal is being produced by irradiating special fuel rods, known as Tritium-Producing Burnable Absorber Rods (TPBARs), in a nuclear power reactor owned and operated by the Tennessee Valley Authority (TVA), a federal corporation. Tritium is then extracted from the TPBARs in a facility at the Energy Department's Savannah River Site in South Carolina.
The fiscal year 2010 request of $68.2 million for "Tritium Readiness" actually represents a slight decline from the $71.8 million that Congress appropriated for fiscal year 2009. But according to the NNSA budget justification-the detailed budget document that federal agencies submit to Congress-"Plans are being initiated to bring additional production capacity on line using TVA's Sequoyah Unit #1 and #2 reactors to meet tritium production requirements, specified in the Nuclear Weapons Stockpile Plan signed annually by the President." TPBARs were first irradiated in TVA's Watts Bar reactor in 2003.
In a May 21 interview, Douglas Dearolph, manager of the NNSA's Savannah River Site office, said the program had always planned to use three reactors. Adding the two Sequoyah units will not affect the "operational strategy" for the extraction facility, he said. Also, he said, although the two additional reactors will increase production capacity, they also simply provide more "flexibility."
The TVA has successfully applied to the Nuclear Regulatory Commission to increase the maximum allowable number of TPBARs. That also is a step that the NNSA is taking to meet program requirements that had been previously "established and planned for," Dearolph said.
According to the budget request, Watts Bar is experiencing "greater than expected tritium permeation into the reactor coolant." But that is not having any significant effect on the amount of tritium generated, Dearolph said. The issue, he said, is the permeation's potential effect on reactor operation. The TVA is "evaluating" the situation and "being responsive," he said.
Meanwhile, the NNSA has reduced staff at the Savannah River Site facilities involved in extracting the tritium and packaging it for use by the Department of Defense. In the past, both facilities had been fully staffed, but now staff is being shared between them, James Giusti, an NNSA spokesman at the Savannah River Site, said May 15. That arrangement, which has been in place since November 2008, saves more than $5 million a year, he said.
The extraction facility does not need to operate around the clock, he said. Because the NNSA does not have to extract as much tritium as it had originally planned, the facility can operate on an "as-needed basis," he said.
Everet Beckner, a former senior NNSA official, suggested going further. In testimony earlier this year to the House Appropriations Energy and Water Development Subcommittee on options for reducing costs at the NNSA, he suggested putting the extraction facility into cold standby, "with the expectation to restart it when it becomes necessary to generate new tritium, in perhaps 10 years."
The move would be feasible, Beckner said, because reductions in the U.S. nuclear weapons stockpile, including those anticipated to be recommended in the forthcoming Nuclear Posture Review (NPR), mean that the NNSA "has adequate quantities of tritium for many years to come."
But Dearolph and Giusti said the NNSA is not currently considering that option.
Beckner's suggestion was predicated on a scenario that has not yet materialized, Dearolph said. Implementation of such an idea typically would follow the completion of the NPR and the establishment of new tritium requirements corresponding to any changes to the nuclear stockpile, he said.