Plutonium experiments at NIF draw fire

Two environmental organizations have asked the US Department of Energy to cancel experiments with plutonium at Lawrence Livermore National Laboratory’s (LLNL’s) National Ignition Facility (NIF). Representatives from the groups claim the experiments could contaminate the massive laser facility and possibly expose workers and the public to the toxic element.

The Natural Resources Defense Council and Tri-Valley CAREs, in Livermore, California, charge that existing environmental impact statements do not include an adequate assessment of the environmental, safety, and proliferation aspects of zapping plutonium with beams from NIF’s 1.8-megajoule laser. The experiments are to be conducted in NIF’s massive 10-meter-diameter target chamber without an inner vessel to contain debris.

“Before these controversial experiments begin, at a minimum we believe the government must undertake a stringent environmental review and solicit public comment pursuant to the National Environmental Policy Act,” said Marylia Kelley, Tri-Valley CAREs’s executive director. “The planned use of plutonium in NIF raises serious nonproliferation concerns,” added Matthew McKinzie, director of NRDC’s nuclear program. “NIF construction and operation was predicated on agency assurances that plutonium would not be used in experiments,” he stated, citing a 1995 review of NIF’s proliferation potential.

But LLNL spokeswoman Lynda Seaver says the environmental impacts of the plutonium “shots” were assessed in a 2005 LLNL sitewide environmental impact statement and in a 2011 supplement to that statement. She says, “The scope of planned operations at NIF is fully consistent with what was disclosed, considered, and approved by DOE” in those documents.

NIF’s target chamber was designed specifically for using radioactive materials in shots and containing all the debris that may result, Seaver notes. Radioactive materials, including tritium, have routinely been used in NIF experiments with no contamination issues., she notes. Materials will be contained primarily in the target assembly or the associated diagnostics. “In the unlikely event that any material escapes the target assembly, it would be contained in the target chamber,” says Seaver.

All the experiments will use plutonium-242, a non-fissile isotope far less radioactive than fissile plutonium-239, which is used in the primary stage of nuclear weapons. The amounts used will range from less than a milligram to 10 milligrams, around the size of a poppy seed.

Seaver says NIF was built in support of the nuclear weapons program, and that support includes experiments to identify the properties of materials at extreme high pressures and temperatures. Such experiments can’t be done anywhere else in the world, she says. The plutonium shots will have no impact on unclassified work at NIF, including experiments performed by outside users.

Activists from the two organizations maintain that the sitewide environmental impact statement had first stated that plutonium experiments would need to be performed within a removable inner containment vessel to prevent contamination of the target chamber. DOE determined later that the experiments could not be carried out inside a vessel but didn’t formally assess the environmental or nonproliferation consequences of that change, the activists contend.