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Nuclear waste: too hot to handle? (February 2013)

Cumbria’s decision to veto an underground repository for the UK shows how hard it is to find a long-term solution

New Scientist  – Magazine issue 2904.

18 February 2013 byWilliam M. Alleyand Rosemarie Alley

THERE are 437 nuclear power reactors in 31 countries around the world. The number of repositories for high-level radioactive waste? Zero. The typical lifespan of a nuclear power plant is 60 years. The waste from nuclear power is dangerous for up to one million years. Clearly, the waste problem is not going to go away any time soon.

In fact, it is going to get a lot worse. The World Nuclear Association says that 45 countries without nuclear power are giving it serious consideration. Several others, including China, South Korea and India, are planning to massively expand their existing programmes. Meanwhile, dealing with the waste from nuclear energy can be put off for another day, decade or century.

It’s not that we haven’t tried. By the 1970s, countries that produced nuclear power were promising that repositories would be built hundreds of metres underground to permanently isolate the waste. Small groups of technical experts and government officials laboured behind closed doors to identify potential sites. The results – produced with almost no public consultation – were disastrous.

In 1976, West German politicians unilaterally selected a site near the village of Gorleben on the East German border for a repository, fuelling a boisterous anti-nuclear movement that seems to have no end in sight.

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Nuclear waste: too hot to handle? (New Scientist)

18 February 2013 byWilliam M. Alleyand Rosemarie Alley, New Scientist

Cumbria’s decision to veto an underground repository for the UK shows how hard it is to find a long-term solution

THERE are 437 nuclear power reactors in 31 countries around the world. The number of repositories for high-level radioactive waste? Zero. The typical lifespan of a nuclear power plant is 60 years. The waste from nuclear power is dangerous for up to one million years. Clearly, the waste problem is not going to go away any time soon.

In fact, it is going to get a lot worse. The World Nuclear Association says that 45 countries without nuclear power are giving it serious consideration. Several others, including China, South Korea and India, are planning to massively expand their existing programmes. Meanwhile, dealing with the waste from nuclear energy can be put off for another day, decade or century.

It’s not that we haven’t tried. By the 1970s, countries that produced nuclear power were promising that repositories would be built hundreds of metres underground to permanently isolate the waste. Small groups of technical experts and government officials laboured behind closed doors to identify potential sites. The results – produced with almost no public consultation – were disastrous.

In 1976, West German politicians unilaterally selected a site near the village of Gorleben on the East German border for a repository, fuelling a boisterous anti-nuclear movement that seems to have no end in sight.

In the UK, the practice of choosing candidate sites with little public input was lampooned as “decide, announce, defend”. In the US, backroom political manoeuvring led to the 1987 selection of Yucca Mountain in Nevada, at the time an under-populated gambling Mecca with no political muscle. Nevadans have been fighting what they call the “Screw Nevada Bill” ever since. The Obama administration pulled funding from Yucca Mountain to appease Senate majority leader Harry Reid, who is from Nevada, but the decision is still being battled in the courts and Congress, and the site is not completely off the table.

It took a while, but governments began to catch on that the top-down approach wasn’t working. Time for a new strategy: look for a community willing to host a repository, using lots of touchy-feely language such as consent-based, transparent, adaptive, phased and terminable. On paper, it is win-win. Sweden and Finland, those paragons of Nordic cooperation and efficiency, are now in the home stretch for opening the world’s first nuclear waste repositories, and are held up as proof-positive that the new policy can work.

Yet finding a volunteer community is the relatively easy part, because nuclear waste repositories bring jobs and money. But this doesn’t mean their neighbours, or the regional powers that be, are going to go along with it.

This unfortunate aspect of policymaking became readily apparent in the UK last month. Everything seemed a sure shot for taking the next exploratory steps toward a nuclear waste repository in west Cumbria. Located next door to Sellafield, the granddaddy of the UK’s nuclear facilities, two local communities comfortable with nuclear matters were in favour. The bugles and bunting were practically being unfurled when Cumbria County Council, concerned about tourism in the Lake District and possible future leaks, vetoed the plan. No other volunteers are in line as a backup.

The US recently announced its own volunteer-based policy, including promises to have an interim storage site up and running within eight years and a repository by 2048. It should know better. Is it forgetting its own track record, even with interim storage facilities?

In the 1980s, the community of Oak Ridge, Tennessee, agreed to host an interim facility. Statewide opposition shut it down. In the 1990s, the Skull Valley Band Of The Goshute Nation, a recognised Native American sovereign nation, volunteered to host an interim facility on its reservation in Utah. Last December, after more than 15 years of legal sparring with the state, the utilities working with the Goshute finally gave up.

The most recent volunteer community to be snubbed is Nye County, where Yucca Mountain is situated. After a commission chartered by the Obama administration recommended a new “consent-based” approach to break the deadlock over the site, Nye County officials wrote to US energy secretary Steven Chu giving their consent to host the repository at Yucca Mountain. Nevada Governor Brian Sandoval subsequently informed Chu that the state of Nevada will never consent to a repository.

It’s now over half a century since the dawn of nuclear energy and dangerous and long-lived waste continues to pile up all over the globe. Something needs to be done. Although touted as the solution, finding a consenting community is merely the first step. The harder part is getting everyone else to sign on.

And then comes the real challenge – to determine if the ground beneath a volunteer community is geologically suitable for a repository. This daunting endeavour requires a decades-long process that is both politically sensitive and technically complex. Inevitably, surprises occur as studies go underground. Here, the public needs an independent, technically savvy group whom they trust to address their concerns and interpret the scientific results.

The difficulties of finding a happily-ever-after triad of volunteer community, consenting neighbours and geologically suitable site cannot be lightly dismissed. Replacing a top-down approach with a consent-based one is a step in the right direction, but it doesn’t fundamentally solve the problem.

This article appeared in print under the headline “Down in the dumps”

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Corrosion of copper in distilled water, detection of produced hydrogen (January 2013)

Publikationer

2013:07

Corrosion of copper in distilled water without molecular oxygen and the detection of produced hydrogen

In this report, results are presented for copper which has been exposed to pure anoxic water in the temperature interval of 21° C to 55 °C up to a total of 19 000 hours. Characterisations of copper surfaces after exposure have been performed ex-situ, meaning after termination of the experiment and exposing the specimen to normal atmospheric environment.

Ideally characterisation of surfaces should have been performed with the specimens in the reaction chamber without oxygen supply but this was not possible in the experimental set-up used. Thus it cannot be excluded that formed species on surfaces could have been altered during handling of specimens between exposure and surface analysis.

The results from the surface analysis of exposed copper specimens indicate that the reaction products are predominately comprised of oxide and hydroxide. Furthermore, based on the visual appearance, the reaction products formed are solid and of a three dimensional character. Moreover, depth analysis by ion sputtering shows that hydrogen is present at greater depth from the surface and inwards compared to oxygen. This indicates that corrosion of copper in anoxic water involves a mechanism in which hydrogen atoms present in water molecules form hydrogen gas which partly dissociate and diffuse into the copper metal as hydrogen atoms


Author: G. Hultquist, M.J. Graham, O. Kodra, S. Moisa, R. Liu, U. Bexell and J.L. Smialek
Publisher: SSM
Language: English
Publication date: 13-01-18
No of pages: 28
Possible to order: Yes
Price per publication: 100 SEK (incl. VAT)
Download: 2013:07 Corrosion of copper in distilled water without molecular oxygen and the detection of produced hydrogen [2836 kb]

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Nuclear fuel rod fragmentation under accidental conditions (December 2012)

December 3

This paper deals with fuel rod fragmentation during a core meltdown accident in a Nuclear Power Plant. If water is injected on the degraded core to stop the degradation, embrittled fuel rods may crumble to form a reactor debris bed. The size and the morphology of the debris are two key parameters which determine in particular heat transfer and flow friction in the debris bed and as a consequence its coolability. To address this question, a bibliographic survey is performed with the aim of evaluating the size and the surface area of the fragments resulting from fuel rod fragmentation. On this basis, a model to estimate the mean particle diameter obtained in a reflooded degraded core is proposed. Modelling results show that the particle size distribution is very narrow if we only take into account fuel cracking resulting from normal operating conditions. It leads to minimum mean diameters of 2.5 mm (for fuel particles), 1.35 mm (for cladding particles) and 2 mm (for the mixing of cladding and fuel fragments). These results are obtained with fuel rods of 9.5 mm outer diameter and cladding thickness of 570 μm. The particle size distribution is larger if fine fragmentation of the highly irradiated fuel rods during temperature rise is accounted for. This is illustrated with the computation by the severe accident code ASTEC, codeveloped by IRSN abd GRS, of the size of the debris expected to form in case of reflooding of a French 900 MW reactor core during a core meltdown accident.

Nuclear Engineering and Design,  Volume 255, February 2013, Pages 68–76

  • Institut de Radioprotection et de Sûreté Nucléaire, IRSN/PSN-RES/SAG/LESAM, Cadarache Nuclear Center, BP 3, 13 115 St Paul Lez Durance cedex, France

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NIMBY: Nuclear in my backyard (September 2012)

Multi-billion dollar Cdn competition moving forward, but launch is decades away. David Nesseth

As if it were a bizarre episode of reality TV, by the end of September 2012, several Canadian communities will be one step closer to winning a competition to host a massive storage facility for the country’s spent nuclear fuel.

9/7/2012 | Full Story  AVAILABLE ONLY WITH A SUBSCRIPTION TO ECOLOG; visit www.ecolog.com/issues/verify.asp

 

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