Britain's worst nuclear accident in recent years occurred in 2005 at its Thermal Oxide Reprocessing Plant (THORP) at the country's Sellafield nuclear complex. A subsequent investigation found that 83,000 liters of spent nuclear fuel had dissolved in nitric acid (some 22 tons worth) and leaked undetected from a fractured pipe for nine months. While the spill was isolated within the plant, cleanup and repair kept THORP closed for almost three years. It restarted in late 2007, but is scheduled to close again this summer for an estimated seven months while the plant's evaporator, which condenses high-level liquid waste, has its internal cooling and heating coils investigated. This most recent closure is further evidence that Britain must finally put an end to reprocessing nuclear waste.
Now in its sixteenth year of operation, THORP has been afflicted by multiple accidents and unplanned closures--some due to worker error and some due to technical problems. Even when operating normally, THORP's performance has been lackluster; converting only 14 percent of recovered uranium into new fuel for export. An even smaller percentage of plutonium has been reused, leaving Britain with an embarrassing stockpile of more than 100 tons of separated plutonium that it doesn't know what to do with. While the domestic nuclear industry maintains that the plutonium would best be used as mixed-oxide fuel (MOX) for light water reactors, the higher cost of MOX fuel compared to conventional low-enriched uranium fuel and the additional security required to safeguard it from theft or attack has dampened consumer interest.
Britain originally started reprocessing spent nuclear fuel in the 1950s to separate plutonium for its nuclear weapons program. Initially, the fuel came from the country's two Windscale graphite-moderated, air-cooled reactors, both of which were closed following an infamous 1957 fire that burned for four days and released a radioactive plume across Britain and Western Europe. Reprocessing later was touted as a way to recycle plutonium and uranium for reuse as fuel in the large number of nuclear reactors that were expected to be built around the world in the 1970s and to preserve natural uranium stocks, which at the time were thought to be insufficient to meet the expected worldwide demand. But the predicted expansion of nuclear power never came to pass, removing the original reason that reprocessing was undertaken.
Since 2005, when the Sellafield site was transferred to the government-sponsored, taxpayer-funded Nuclear Decommissioning Authority (NDA), THORP has remained under constant government and NDA review. Its operations have been tolerated by the NDA not on its merits as a recycling facility but because it still earns cash from reprocessing orders signed decades ago, mainly from Japan but also from Britain and six other European countries. Such revenue, which is included in Sellafield's overall income, was approximately $1.2 billion in fiscal year 2008.The money helps pay for the cleanup costs of Sellafield and other British nuclear facilities, currently estimated at $108 billion and growing. Without this revenue, THORP might already be closed and Britain's failed reprocessing policy abandoned for good.
But any profits derived from reprocessing are outweighed by the contamination caused by discharges to the environment, the unnecessary creation of large amounts of dangerous high-level and other radioactive wastes, and other problems associated with the facility. In tacit recognition of these detriments the British government has already announced that spent fuel from future reactors will not be reprocessed. Instead spent fuel will be stored up to 100 years at reactor sites prior to permanent underground disposal. Although this is exactly what should be done, this policy should be accelerated. With THORP currently closed, it should never be reopened. Existing reprocessing contracts should be cancelled now and the spent fuel placed in dry-cask storage for eventual permanent disposal. Any so-called advantages of reprocessing have not yet materialized in 15 years of operation. Britain should admit its failure and move on.