The US Department of Energy (DoE) has ordered the permanent shutdown of the Hanford Fast Flux Test Facility (FFTF). US energy secretary Spencer Abraham said a restart of the reactor, which has been on standby since 1992, was impractical.

The decision followed a 90-day review of possible future uses of the FFTF research reactor. During the review, only one commercial proposal, submitted by the Advance Nuclear and Medical Systems (ANMS), was deemed worthy of further analysis. However it was concluded that the ANMS proposal presented “potentially new legal and financial liabilities” to the DoE.

Abraham said: “The department’s final determination is based on sound science, an extensive analysis of the costs and benefits of disposition options and an in-depth consideration of commercial use options.” The 400MWt, sodium-cooled reactor first achieved criticality in 1980 and is the DoE’s newest reactor. It was designed to research plutonium-uranium dioxide fuels for breeder reactors, but the US breeder programme was scrapped in the 1980s. The reactor costs between $30 and $40 million a year to maintain. Shutting down the FFTF could take about five years and cost as much as $300 million.