Inside the cavernous hall of a nuclear storage plant in southern Sweden, an 18- ton steel canister, bristling with tiny fins to draw out excess heat, is being hauled slowly through a hatch by a crane.
Packed with highly radioactive spent nuclear fuel from a reactor north of Stockholm, the canister is being made ready for 30 years of storage in pools sunk into the bedrock. Once it cools sufficiently, it will be placed permanently in a final repository deep underground.
Surrounded by picturesque pine forests, lakes and rocky islets, Oskarshamn might seem an unlikely location for the 4705 tons of high-level waste that is the legacy of Sweden’s 40-year nuclear programme.
But to many in the industry, this unassuming plant on the shores of the Baltic represents the most advanced method yet developed for handling nuclear waste — and offers valuable lessons for SA as it embarks on the construction of a new generation of nuclear reactors. Britta Freudenthal, of the Swedish nuclear waste management company SKB, offers a rather sobering insight into why most countries have found decisions over the handling of this hazardous material so difficult. Should the fuel rods be withdrawn from their protective canister and exposed to the open air, “you would need to be at least 20km away to be safe from the radiation they emit”, Freudenthal says. Furthermore, they will remain highly radioactive for up to 100000 years.
“It doesn’t matter whether or not we are committed to building any more reactors or not,” says SKB’s Jenny Rees. “We need a safe place to store the waste we have already created. It is our responsibility to future generations.” That is why the Swedish government will pick a site this year for its final repository from two possible locations, including one just a few kilometres from Oskarshamn. The planners say construction will start in 2012. Studies of the bedrock to identify a geologically stable site have been accompanied by intensive research on how to package and store the waste safely. Once the final repository is built by about 2018 at a cost of £1.8-billion, Sweden’s spent nuclear fuel will be taken from the interim store, encased in solid steel and then welded inside five-metre-high canisters made from pure copper, 5cm thick. The canisters will then be transported into a deep underground store, between 400m and 700m beneath the surface. — ©The Times, London
