There currently are no facilities for permanent disposal of high-level radioactive waste, according to the World Nuclear Association (WNA), and nuclear countries are wrestling with the conundrum.
Since decay is the only way radioactive wastes finally become harmless – and that can take hundreds of thousands of years – the wastes must be stored in a way that provides adequate protection for very long times.
Presently in the United States, spent fuel is being stored in large water-cooled pools and dry storage casks at nuclear power plants. Also, U.S. defense-related transuranic radioactive waste is stored about 3,000 feet deep in a bedded salt-deposit located in the Chihuahuan Desert, outside Carlsbad, N.M.
Existing high-level wastes from reprocessing are presently stored at West Valley, N.Y.; Hanford, Wash.; Idaho Falls, Idaho; and Savannah River, S.C. Liquid high-level wastes are stored in large underground tanks of either stainless steel or carbon steel, depending on whether they are acid or alkaline.
Some of the liquid waste has been solidified into glass, ceramic slag, salt cake and sludge.
Here is a roundup of other countries’ plans:
♦ Russia ’s policy is to close the fuel cycle as far as possible and utilize recycled uranium, and eventually also to use plutonium in mixed oxide, or MOX fuel, an alternative to low enriched uranium fuel used in the light water reactors.
The WNA reports that its achievements in doing this are limited.
At present the used fuel is stored (mostly at reactor sites) and not reprocessed. No waste repository is yet available, though site selection is proceeding in granite on the Kola Peninsula.
In Europe some spent fuel is generally stored at reactor sites, similarly awaiting disposal, according to the WNA.
♦ France has more than 30 years of experience transporting and reprocessing radioactive waste and reprocessing at La Hague and at the Marcoule facility on the Rhone River n ear the southern city of Orange.
Spent nuclear fuel and high-level radioactive waste are shipped by rail within France; trucks carry the materials over short distances. Five ships transport the material inter-coastally. Spent nuclear fuel arrives at La Hague by train in specially designed rail cars, as railway traffic.
A 15-year study that culminated in a 2006 report called for more study in the Bure area for a permanent high-level waste geologic disposal site, with a decision by 2015 and commissioning by 2025.
In 2002, France stored 978,000 cubic meters of waste. In 2020, the annual amount is expected to be 1.9 million cubic meters, according to the Commissariat a l ’Energie Atomique.
♦ Belgium, Germany, the Netherlands, Switzerland and Japan also send, or have sent in the past, spent nuclear fuel to France or to Sellafield in the United Kingdom for reprocessing. The recovered materials are returned to the owner and the separated wastes are vitrified, sealed into stainless steel canisters and either stored or returned. Eventually they too will go to geological disposal.
♦ Sweden has centralized spent fuel storage near Oskarshamn and will encapsulat e spent fuel there for geological disposal by about 2015.
Sweden currently is carrying out additional research to reach a decision between the Östhammar and Oskarshamm sites for a permanent disposal solution.
♦ Finland , which formerly sent its waste to Russia for handling, has two long-term disposal sites for lower-level waste and is constructing a third. At the end of 2004, the sites held 5,400 cubic meters of waste.
♦ In Canada , the Nuclear Waste Management Organization said earlier this year that a final repository probably would be in Ontario, Quebec, New Brunswick or Saskatchewan, and host localities would need to volunteer for the role.
The search for a site was expected to begin in 2009.