Finland buries its nuclear past | By Richard Black Environment Correspondent, BBC website  An unprepossessing tunnel entrance set in low forest on the western coast of Finland marks the probable final resting place of the country's most dangerous nuclear waste. While British authorities agonise over what to do with the legacy of half a century of nuclear power, Finland is one of a handful of countries which has embarked on the journey towards a "final" waste solution |
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Enter the 6.5m-high, 5m-wide (20ft-high, 16ft-wide) Onkalo tunnel, and you would drive down a spiralling track which will eventually stretch 5km (3miles) through solid rock, reaching a depth of 500m (1,600ft).
The first travellers to go down the tunnel will be investigators aiming to demonstrate that the rock is structurally sound enough to proceed with the disposal of spent fuel rods containing plutonium and other unpleasant materials.
If they were to turn up a positive result, and if government agencies grant the necessary licences, the first canisters of spent fuel would begin rolling down the tunnel about 15 years from now.
As things stand, Finland is on course to become the first country in the world to entomb its most troublesome nuclear waste in a designated final resting place.
'Multiple barriers'
The Onkalo facility is run by the company Posiva, and the system it uses is a Swedish concept called KBS3, which Sweden's proposed repository would also implement.
 The Onkalo tunnel will spiral to a depth of 500m |
The other country close to solving its problem, the US, is exploring a different technology at its Yucca Mountain site.
"The safety concept is based on so-called 'multiple barriers'," says Timo Aikas, Posiva's vice-president in charge of engineering.
"One barrier is of course the solid stable crystalline rock. The remaining barriers are engineered barriers, the most important of which is long corrosion-resistant copper canisters, inside which we put the actual fuel rods."
In this vision, the bottom of the Onkalo tunnel would sprout a grid of horizontal shafts.
Canisters containing the spent fuel rods would be deposited into holes in the bottom of each shaft.
The canisters would nest in a bed of bentonite clay, which swells when it absorbs water. This comes with twin benefits; cushioning the cargo from geological movement, and ensuring there are no voids where substantial quantities of water can penetrate, corroding the canisters and carrying away their radioactive contents.
As each canister goes in, the tunnels would be filled up again with yet more clay and rock.
By 2100, the repository would be complete, access routes would be filled and sealed. What to do next would be a decision for Finns of that era; but the concept is designed to allow them, if they want, to cover the tunnel mouth, landscape it and walk away, leaving no entrance into the rock and no sign of the material buried underneath.
A granite curtain would have descended on the first civilian nuclear epoch.
Through the ice age
Some of the radionuclides - atoms with unstable nuclei that undergo radioactive decay - in spent fuel rods remain radioactive for more than 100,000 years. In that time, could not even the tiny quantities of water which the bentonite allows through penetrate the copper canister shells, allowing dangerously active isotopes to escape?
Timo Aikas believes not. "We have seen that the copper canister will not be corroded away," he says.
"We have native copper in the Finnish and Swedish bedrock, which means we have good conditions for such things. We know from corrosion testing that 1.5cm [thickness] of copper would be enough from the corrosion standpoint for times longer than 100,000 years, but we have 5cm (two inches) copper."
The time period is so mind-bendingly long that it will almost certainly take the world through another ice age; which, if history is a guide, would bury Finland and Sweden under 2-3km of ice.
 Fuel rods are placed inside a steel cylinder cased in copper |
The huge pressures created by this ice will certainly deform even bedrock, compressing the copper canisters and fuel rods which lie inside (the rods are contained within channels bored into a steel cylinder).
So concerned have European authorities been about this that the European Commission's Institute for Energy in the Netherlands commissioned pressure tests on the steel cylinders.
"The maximum [ice] thickness is 3km, which equates to a pressure of 30 megapascals (MPa)," says the engineer in charge, Kalle Nielsson.
Combined with pressure from groundwater and the tight embrace of bentonite clay, the cylinders would experience a total pressure of 45 MPa, which corresponds to the pressure you would have 4,500m (15,000ft) down in the ocean.
In tests, the cylinders stood up to a pressure three times that value before failing.
"I would say that it's safe," is Kalle Nielsson's conclusion. "And we have made a probabilistic calculation - 'what is the probability that it would fail at this 45 MPa?' - and it is less than one out of a million canisters that would fail. So I would say as a concept that it's safe."
Far-sighted funds
Technology is only one part of the Finnish solution; the other vital component is finance.
"Our current cost estimate for this 'funeral' is about 3bn euros," says Timo Aikas.
The signs point in a different direction. The advent of commercial nuclear power to Finland in the late 1970s saw the establishment of a fund to pay for the eventual clean-up.
"Every year, we have re-calculated the fund based on the amount of spent fuel accumulated," says Timo Aikas, "and at the moment the fund is approximately 1.4bn euros."
The money has come from generating companies through a small levy on the price of nuclear electricity.
It is, perhaps, the sort of measure which current British leaders looking at a waste disposal facility bill in the region of £10bn (14bn euros) would wish their predecessors had chosen to implement.
Rocky site
Even if the KBS3 concept is sound, even if Finland has the money to implement it, there is a question over whether Eurajoki is the best place to put it into action.
Greenpeace, which has been spearheading a campaign against the new Olkiluoto-3 nuclear reactor taking shape just a kilometre from the Onkalo site, is concerned that the local geology may not be the soundest available.
 Construction work on Finland's new reactor proceeds nearby |
"When the site selection started in Finland, the nuclear industry said they would find the best geological site," says energy campaigner Kaisa Kosonen.
"And, eventually, they chose the site on sociological reasons, because eventually Eurajoki was the first municipality to say 'ok, we can take it', and there wasn't an active nuclear opposition in this area."
That lack of local opposition may be down to the fact that nuclear reactors have stood in the area for three decades, gaining acceptance for an industry which has maintained a good local safety record and brought employment.
"It boils down basically to trust," comments Timo Aikas.
"When you make a decision concerning this kind of thing, which takes us to 2100 when the final sealing takes place, there will always be uncertainty. So you have to have trust."
Kaisa Kosonen urges caution; the case for Onkalo, she says, is not proven.
"I would like to see much more research done and not having this hasty process," she says. "And I would not want this marketed as 'waste issue solved', because it's not."
But Timo Aikas believes his system and his team deserve the trust they have found in Eurajoki, and that Onkalo will prove as safe a resting place for highly active radionuclides as can be found, barring any surprises with the local geology.
And he urges other countries, Britain included, to take a decision and find a solution.
"Nuclear waste doesn't go away," he reflects.
"And if we just keep it in stores above ground we just push the problem Time for action on nuclear waste | ANALYSIS
By Richard Black
Environment correspondent, BBC News website |
  |  For over three decades, efforts to find solutions to the problem of long-term radioactive waste management in the UK have failed  |
"Now is the time to get on with the job."
Gordon MacKerron, chair of the Committee on Radioactive Waste Management (CoRWM), could not have been clearer in his message to government as CoRWM released its final recommendations on dealing with Britain's nuclear waste stockpile.
It is an issue which administration after administration has either ducked or failed to push through.
As the report puts it: "For over three decades, efforts to find solutions to the problem of long-term radioactive waste management in the UK have failed."
The resulting situation, which sees waste stored in various forms on a multiplicity of sites, is one which almost every informed observer from academia, industry and the environmental movement finds unacceptable; and one which CoRWM was set up three years ago to help resolve.
It has been exhaustive in its trawl of global scientific expertise, and has taken discussions into the public domain with openness unprecedented in Britain's notoriously secretive nuclear history.
| NUCLEAR WASTE MAP Where waste is produced and stored around the UK 
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Now, it is above all else urging action. Assuming the government accepts CoRWM's recommendations, it should establish a body to oversee implementation "without delay".
"It would have an independent character; it would build on public trust," said Professor MacKerron.
"It will also need to decide, as soon as it can, on which body would do the implementation of radioactive waste facilities, and would begin the process of thinking about how to screen the country for geological unsuitability at least in the first instance.
"Those things at the very least, as well as, in addition, thinking about establishing a better research programme - those are all things I would expect to see before the next general election."
Into the void
So are we any nearer to knowing when the first batch of "high-level, relatively dangerous radioactive waste" will be consigned to its final resting place?
Not really; though we do have, assuming the government follows CoRWM's advice, a clearer idea of what the final resting place might look like.
Accessibility allows monitoring of canisters for signs of failure. It also means that spent fuel could be retrieved for reprocessing if technological or economic factors made that option desirable.
CoRWM's view is that these advantages are outweighed by the disadvantages: the continuing need for a human presence, which brings health risks and expense; and potential terrorist attack. Facilities should be closed after emplacement of waste, it recommends.
On the technology itself, which would see spent fuel and other waste encased in materials such as steel, copper or carbon and immersed in clay, it has few doubts, though it does note that "further clarity" is needed on the length of time for which containers will remain intact.
Half life
There will also need to be "robust interim facilities" which would store material before it was sent for disposal, CoRWM says. These facilities would need a lifetime of more than a century.
The clearest recommendation comes on the social side, where the committee is in no doubt that the old approach - find a disposal site and tell people living nearby they are going to have to lump it - must be consigned to the disposal bin of history.
| OLD NIREX PROPOSED SITES Bradwell, Essex Potton Island, Essex Two sites at Sellafield, Cumbria Dounreay, Caithness Altnabreac, Caithness Fuday, Hebrides Sandray, Hebrides Killingholme, South Humberside Stanford, Norfolk Offshore site near Redcar Offshore site near Hunterston |
Public resistance was the key factor in the abandonment of proposals for deep disposal conceived in the 1980s by the Conservative government and the company Nirex.
"We believe there must be a willingness on the part of communities to participate," said Andrew Blowers, a CoRWM member and Open University social scientist, when the committee released interim recommendations in April.
"Indeed, the basis of participation can only be that those communities get an enhancement of their well-being."
CoRWM takes no position on the scale or nature of such an "enhancement", though it notes: "In South Korea, communities were offered up to $290m [£156m] to allow the implementing body to select a low-level waste repository."
The committee has found signs in its consultations around the UK that some communities might welcome the jobs which continued involvement in the nuclear industry can bring.
Long stretch
The government has welcomed CoRWM's report. But even if it acts with the urgency which Professor MacKerron demands, this is clearly the beginning of a very long process.
To start with, only about one-fifth of the estimated 470,000 cubic metres of the waste which will result from Britain's existing nuclear power, research and military programmes already exists as waste; the rest is tied up in the fabric of nuclear installations as spent fuel, reactor vessels, contaminated structures, and such like.
By definition, this material cannot be disposed of until it has come out of use; even then, some must be left to cool off for decades before processing begins.
Even with the speediest political decisions, the first canisters of waste are unlikely to be buried for 35 years, CoRWM says.
Other countries are moving faster; Finland has already mapped out a pathway and started excavating a likely site. It is heading for a mere 20-year gap between deciding on deep disposal and seeing the first canisters interred.
But Britain, the committee maintains, is different; the geology is more complex, the waste more varied, and the social questions more difficult.
The waste issue has also, inexorably, become linked to the vexed question of whether to build new nuclear reactors in the UK.
The government has said it would not embark on a new round of building until and unless a solution had been found for waste from previous nuclear programmes.
Would acceptance of CoRWM's recommendations constitute a solution?
The government's endorsement of the principle of new build in its recent energy review suggests it believes the argument has been settled.
But anti-nuclear groups, which base their arguments largely on the danger of waste and the costs of clean-up, can point to CoRWM's ambivalence on the longevity of containers and its acceptance that disposal facilities will cost at least £10bn.
The nuclear industry seeks to de-link new build from waste with its assertions that technology has changed and that waste from a new generation of reactors would add only 10% to Britain's existing stockpile.
But likely timelines for the two issues coincide; and communities which might accept a disposal facility are also likely to be in areas where enthusiasm for new reactors runs highest.
But pushing ahead with either new build or waste disposal facilities may be hampered by issues other than public acceptance.
Contracts will have to make financial sense to commercial partners; and unions are warning of a skills shortage.
CoRWM has laid down a set of boundaries within which government can act, and a "least-worst" pathway for this most hazardous of issues.
Continued willpower over the lifetimes of many parliaments will be needed to follow the pathway to its logical conclusion, half a kilometre below Britain's surface.
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to the next generation. It's much more responsible now to develop solutions on how to take care of it." 'Speed needed' on nuclear waste | By Mark Kinver
Science and nature reporter, BBC News |
 Much of Britain's waste is stored at the Sellafield site |
It is now "time to get on with the job" of burying the UK's radioactive waste deep underground, a nuclear advisory group has said in its final report.
The Committee on Radioactive Waste Management (CoRWM) urged ministers to create quickly a body to oversee the process of identifying suitable sites.
Because building disposal facilities would take decades, CoRWM said current storage methods also needed reviewing.
The report is the culmination of a 30-month study into the issue.
CoRWM's chairman, Gordon MacKerron, said the report provided a realistic roadmap for the problem of tackling the UK's growing radioactive waste.
| It is important that the government should review current storage arrangements to check that they are going to work within the context of our recommendations |
"We have about 30 years' worth of not managing the long-term problem of radioactive waste at all satisfactorily," he told reporters at a briefing in central London.
"Although it will take several decades... we think we have now set a direction that government can follow and where there will be at least sufficient public confidence to move ahead.
"Early action is important. We think the government should build on the momentum that we believe we have helped to create."
The committee's recommendations were broadly welcomed by the scientific community.
"Geological disposal, including boreholes, of immobilised waste is the correct solution for radioactive waste," said John Roberts, from University of Sheffield's Department of Engineering Materials.
"It is important that the government now heed the recommendations [and] progress without delay."
| UK NUCLEAR WASTE - VOLUMES AS PACKAGED FOR DISPOSAL High-level waste - 2,000 cubic metres Intermediate-level waste - 350,000 cubic metres Low-level waste - 30,000 cubic metres Spent fuel - 10,000 cubic metres Plutonium - 4,300 cubic metres Uranium - 75,000 cubic metres |
However, David Ball, of Middlesex University, who resigned from the committee, said its findings were based on opinions rather than sound science.
"The CoRWM experience has been the antithesis of good decision making, having been infused throughout with political, commercial and self interests," he claimed.
He added that the findings would be fair game for cries of "foul play" from its detractors.
Greenpeace said the report was likely to be used by the pro-nuclear lobby to push for new nuclear power plants.
"It seems inevitable that CoRWM's 'solution' will be part of the justification for building a new generation of nuclear reactors that create yet more radioactive waste," a statement by the environmental group said.
The committee rejected this view, saying the idea of building new reactors was not on the political agenda in 2003 when they began their study.
'Integrated package'
The committee's key recommendations include:
- In the long term, "geological disposal" is the most suitable option
- The need for "robust interim storage" because the process of identifying and building such a disposal facility may take "several decades"
- The immediate creation of an "oversight body" to begin implementing the committee's recommendations
- An "equal partnership between government and potential host communities"
Professor MacKerron said the committee viewed its findings as an integrated package and did not want individual points to be "cherry picked". "It is vital that government no longer tries to impose radioactive waste management facilities on communities because we have about 30 years of experience of that and we know it never works; it always runs into the sand," he said.
"Instead, we are proposing there should be an approach in which communities are invited to be 'willing to participate'".
Professor MacKerron described it as: "A partnership approach in which the implementing body and the local community can negotiate on equal terms.
"Communities would have the right to withdraw from that process up to a pre-determined point."
Any communities interested in hosting a site for deep geological storage would have to be willing to accept a long-term commitment, the committee warned.
At best, the site would not be ready to accept its first consignment of radioactive waste for at least 35 years, and would continue to receive waste for a further 65 years.
The committee estimated that it would cost £10bn to build a deep burial facility, but warned that this figure was likely to rise.
Another additional cost could come from interim storage of the waste while the repository was constructed, Professor MacKerron added.
"Historically, we have always managed [temporary] storage as if it only has to last for the next 20 or 30 years. We are saying that storage may have to last for 100 years or more.
"Existing storage arrangements may or may not be satisfactory but... we think it is important that the government should review current storage arrangements to check that they are going to work within the context of our recommendations," he said.
CoRWM's final report marks the completion of a two-and-a-half year study, on behalf of the government, into the issue of dealing with the nation's radioactive waste.
In April, it published an interim recommendation that the best long-term solution for the disposal of the material was to bury it deep in the ground, but the committee was not asked to identify places in the UK where disposal would occur.
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