Some of the radionuclides in spent nuclear fuel will stay radioactive for 100,000 years. But on current rates of progress you might be forgiven for thinking that is how long policy makers reckon they have got before they have to make a decision on what to do with the waste.
More than half a century after the onset of the Atomic Age, there is still not a single country on earth that has a geological repository for high-level nuclear waste disposal. Only two nations, Finland and Sweden, are likely to have one any time soon.
Finland’s Onkalo repository, being built by Posiva on the island of Olkiluoto near two of the country’s four nuclear power plants, is expected to open for business in 2020, according to a schedule set by the Finnish Government in 1983.
Posiva has just finished boring a test hole in a demo tunnel. “It’s looking good,” says Timo Seppälä, the company’s senior communications manager.
In Sweden, meanwhile, the waste disposal facility planned alongside the Forsmark nuclear power plant by Svensk Kärnbränslehantering (SKB) is currently on track to start operating by around 2025, pending government approval, says press secretary Jessica Alsenlid Otterstål.
Both will use a technique called KBS-3 (for Kärn Bränsle Säkerhet, or ‘nuclear fuel safety’ in Swedish), developed by SKB, where waste is buried 400m to 500m down behind four separate barriers: bedrock, tunnel backfill, bentonite buffer and copper-cast iron canister casings.
Understandably, the repository operators are keen to emphasise the safety of their designs. Posiva information officer Helena Urpulahti says: “Onkalo was selected because we have two power plants here already and the bedrock is very good. It’s very stable.”
In fact, Posiva asserts that the Olkiluoto granite bedrock is more than 1.8 billion years old and has remained in the same condition for millions of years, which is an important consideration given that Onkalo may have to withstand a future ice age before its quarantining work is over.
Nicole Bockstaller, press officer for energy at the European Commission, defends the choice of disposal technique chosen by Finland and Sweden. “From a scientific and technical point of view there is a large consensus that deep geological disposal is the preferred option,” she says.
Besides the technical aspects of the projects, other countries might want to bear in mind Sweden and Finland’s experience of the costs of final repositories. With both projects still far from being finished, Onkalo is currently estimated to cost around €3.3bn.
Meanwhile in Sweden, the Radiation Safety Authority last year recommended tripling the fees that the nuclear industry paid towards waste management after estimates for the cost of the Forsmark repository grew by a reported €2.1bn above the level forecast in 2008.
Alsenlid accepts that the cost of the repository has risen as the project has progressed. “It has changed during the years,” she says. “We do a calculation that we send to the authorities every third year and you can see that the costs are higher now than a few years back.
“We also have the decommissioning of the power plants; the owners of the plants hadn’t had clear plans back then so it was difficult to estimate how much the decommissioning would cost. Costs are higher than we thought a few years back, but it’s not a very significant up-rise.”
Sweden and Finland have both approached the cost issue by getting nuclear operators to cover the expense of building final repositories. Adding to the outlay is the extremely long time it takes to plan, approve and develop the facilities.
Seppälä says Posiva “started in the 1980s.” SKB, meanwhile, does not expect to get the government green light on its application to build a repository at Forsmark until 2014 and anticipates construction may not start until 2017.
And both companies are lucky to have the local communities on their side.
In fact, Posiva has come under fire from environmental groups claiming that the site for Onkalo was chosen more because the community was amenable to it than because of its geological suitability, although Seppälä says all the sites considered had already met geological criteria.
SKB has also made community relations a major pillar of its nuclear waste disposal strategy, to the point of giving a municipality that lost out in the bidding for the site a reward simply for taking part.
The company is now actively seeking to share its knowledge of repository development with international partners, and countries that are still dragging their feet over the issue of nuclear waste disposal might be wise to sign up.
After all, says Michael Napper, managing director of UK-based Nuclear Decommissioning Services: “Everybody needs a waste repository. Who is going to put up a building that is going to last tens of thousands of years?”
Source: NuclearEnergy Insider