Nuclear power epitomises the problems of technology choice
we face. While some see it as a valuable and reliable energy source, its
critics say that it it locks us into an inflexible, unforgiving, costly and
risky pattern of reliance into the far future, with uncertain payoffs.
They say these characteristics, and the troubled legacy we have already
inherited, imply a need to consider long term ethical and moral issues, as well
as shorter term economic, and strategic concerns, and should give us reason to pause before making any further commitments.
There is no question that nuclear fission leads to the
production of very long-lived and very dangerous nuclear wastes. OU Emeritus Prof. Andy Blowers has produced a
new Earthscan book focusing on the
waste management issue, and underground geological waste disposal, which is
where long-term intergenerational ethical issue come to the fore. What right do
we have to bequeath future generations problems we can’t solve? In the shorter term, on what basis can
communities be asked to accept the risks and uncertainties of hosting a nuclear
waste disposal facility into the far future?
By looking in detail at examples around the world, he identifies
some key characteristics for sites that have been selected or proposed. They
have almost all been in peripheral, often economically weak areas, where local
resistance and political opposition was usually unlikely or muted. In most
cases, the waste sites have followed on from earlier nuclear projects: once a
beachhead had been established it was easier to expand it, with economic
lock-in maintaining the momentum. So attractive is this existing-site option
that it almost seems to override technical geological suitability.
The specifics of the proposed disposal approaches also seem to
reflect concerns about local and wider public reactions. Ideally, to reduce
public concern, long-lived wasted should be buried deep and permanently, so
that they can be forgotten about: out of sight, out of mind. However, this may not be the most rational approach. It is
possible that, in the centuries ahead, new technologies
will emerge that can make use of some of these waste- extracting value and reducing their hazards. In which case continued accessibility
would be important. That may also be important if anything goes wrong with the
disposal approach, or if new better disposal approaches emerge. So the spectrum of options runs from full
final irretrievable disposal to accessible long term, but still underground, storage.
How long it would be possible to maintain accessibility is
unclear: there will be limits. Moreover, in practice it will be many decades
before much of the waste currently in interim surface stores, or being
produced, can be disposed of in underground repositories of whatever sort. So
for good or ill, we have time to see what else can be done with it. But the inescapable bottom line is that it
will have to go somewhere. This book explores the social and local community
dimensions involved in that choice, but also inevitably highlights the fact
that producing yet more of it will make finding a home for waste even harder.
The current state of play in the UK is that a site for final geological
disposal of the UKs high level nuclear waste is still being sought, with
communities being invited to host it, possibly in return for substantial
funding for local social projects. So far the only offer has been for a site in
Cumbria, near Sellafield, backed by the local Copeland and
Allerdale district councils. However, that was strongly opposed by Cumbria County
council. Provocatively, the government
then indicated it might give local councils the final say, but so far no
decision has emerged: www.theguardian.com/environment/2013/sep/12/county-councils-nuclear-waste-dump-sites
The aim is still to have a site chosen somewhere ready for it to
be started up by around 2040, but with opposition likely to be strong, it may
have to be imposed. Moreover, it would take time to build and would be
earmarked preferentially for the existing/current legacy waste, possibly to be
loaded up from around 2060 onwards. There would not be room for the wastes from
the new plants that are currently proposed to start up in the late 2020’s until
around after around 2130! That would be long after these new plants would have
closed, even assuming 60 year operational lives. www.gov.uk/government/uploads/system/uploads/
attachment_data/file/168047/bis-13-630-long-term-nuclear-energy-strategy.pdf
At present it is not proposed to reprocess the highly-active spent
fuel from these new plants, so as to extract plutonium. That means that, thankfully,
the production of large amounts of secondary wastes would be reduced:
reprocessing creates a lot of intermediate and low level wastes. However, the
aim is to go for high burn up of fuel, so as to improve the fuel economics:
more highly enriched fuel is used, able to stay in use longer, generating more
energy before fuel changes are need. But
that also means the waste fuel, with more plutonium and other byproducts
included, would be much more active than conventional reprocessed fuel would
have been. That would make its ‘temporary’ storage, on site at the new plants
around the UK, harder, with ‘temporary’ meaning maybe 100 years before it could
be finally disposed of when and if the national geological repository became
available.
Meanwhile, there is the large amount of the low and intermediate
level wastes, most of which at present is stored at Sellafield, though,
provocatively, some lower level material seems likely to be destined for
regional distribution in selected land fill sites. In addition, the fate of the
140 tonnes plutonium that has already been extracted from earlier fuel remains
unclear: http://researchbriefings.files.parliament.uk/documents/POST-PN-0531/POST-PN-0531.pdf.
Like most the rest of the high level nuclear waste, it’s in
temporary storage at Sellafield. Most of it is from UK plants. The governments
preference is for the plutonium to be used along with reprocessed or depleted uranium
238, in Mixed Oxide Fuel (MOX), possibly for use in some of the proposed new
reactors. That would involve building a new multi billion pound MOX fabrication
plant.
However, all that awaits the construction of the new power plants
and a decision on MOX seems unlikely before they are built and running, if they
go ahead- in the late 2020s/early 2030s. http://corecumbria.co.uk/briefings/new-build-reactor-delays-put-sellafields-plutonium-decision-on-the-back-burner/ And of course, if built, whatever
fuel they use, the new plants will create yet more plutonium and wastes, so the
problem continues into the far future, unless new technology emerges. It is
conceivable that new types of plants could be developed that burnt up
plutonium and some of the wastes, but that seems long off with unknown risks
and costs, and there would still be some wastes to deal with, even with
advanced fast neutron/molten salt/thorium reactors.
As can be seen, the waste issue is complex and
very long-term, and arguably best reduced by not producing more. Though we have to deal
with what already exists- including around 1,400 cu meters of high level waste
awaiting disposal somewhere: https://ukinventory.nda.gov.uk/. However, it won’t be easy getting agreement on where any of it is to
go, as Blowers’ book makes clear, and as this recent review also concludes: https://rwm.nda.gov.uk/publication/societal-aspects-of-geological-disposal/
The hunt for a site is supposed to
start in earnest in 2017…
No comments:
Post a Comment