Waste management

UK cleanup: you decide

21 August 2005



The UK’s Nuclear Decommissioning Authority’s draft strategy for consultation outlines plans to cleanup £56 billion ($101 billion) worth of nuclear liabilities at 20 civil nuclear sites.


The 11 August release of the UK’s Nuclear Decommissioning Authority’s (NDA’s) draft strategy for consultation was, according to NDA chairman Sir Anthony Cleaver: “A major step forward in that we have got a coherent plan for decommissioning all our civil nuclear plants.”

The draft strategy details:

  • Plans to launch competitions for the operation and management of 13 sites by 2008.
  • Plans to accelerate decommissioning timescales of Magnox stations.
  • Evaluation of options for interim storage of intermediate-level radioactive waste.
  • New solutions for the disposal of low-level waste.
  • A consultation process to agree site end-states and timescales.
The top priority is to reduce potential high hazards. On this, Cleaver said: “We’re talking here particularly of the legacy ponds and silos at Sellafield. And we have asked British Nuclear Group to come back to us with a plan to accelerate the way in which they are tackling that.”

Once British Nuclear Group (BNG) provides the NDA with comprehensive and costed plans for the decommissioning of the Sellafield facilities, the NDA will “present a reasoned case to the government for increased funding,” according to the draft strategy report. The NDA’s plan calls for the decommissioning of the plants and facilities at Sellafield within 75 years.


Sellafield
Credit: bnfl
The Sellafield site in Cumbria, which transferred from BNFL to the NDA on 1 April 2005


ACCELERATED SCHEDULE

In addition to bringing forward the decommissioning of the Sellafield site, the NDA proposes having all 11 Magnox reactor sites cleared within 25 years. Up until now, the plans assumed around 10-15 years of work to contain the higher radiation areas followed by a 60-70 year cooling down period, before completion of decommissioning. Cleaver commented: “Based on experience elsewhere in the world, it should be possible to accelerate that process significantly.”

By accelerating the cleanup of the sites, the security and safety issues that would be required during the 60-70 year cooling down period are reduced. In addition, there is a positive impact on employment. “The current plan would assume that after 15 years or so, the level of employment on those sites goes down almost to zero. Then somehow, 60 years later, we have to re-emerge with the appropriate skills to finish the job,” said Cleaver. Bringing forward the decommissioning schedule would allow the NDA to “offer significant employment opportunities over a continuous period from now, which is obviously beneficial in socio-economic terms, while also enabling us to maintain the skills.”

As well as the cleanup of the Magnox sites, the NDA also expects to clear a number of the other sites – namely Harwell, Winfrith, Culham and Capenhurst – over the next 25 years.

MANAGING THE WASTE

As with most decommissioning programmes around the world, the Achilles’ heel of the NDA’s envisaged plan is the question of where to put the waste. Currently, the government’s Committee on Radioactive Waste Management (CoRWM) is carrying out a review of the options for the long-term management of intermediate-level radioactive waste (ILW) and high-level waste (HLW). CoRWM is due to present its recommendations to the government in July 2006.

The extent to which the NDA is dependent on a solution to final disposal is highlighted in the draft strategy. “Any delay in the delivery of CoRWM’s recommendations, the government’s subsequent decisions or in work to implement the long-term management arrangements would have significant implications for the NDA,” it states. Such a delay would affect the accelerated cleanup of the Magnox sites and limit the NDA’s ability to reduce its cleanup costs.

Furthermore, the NDA wants to consider whether to rationalise the interim storage of ILW, which is currently stored on each site as it arises. Failure to implement a long-term waste solution soon after CoRWM makes its recommendations will also prevent the rationalisation of ILW storage arrangements.

Based on the experience of many countries including the UK, it is highly risky – even fantastical – to draw up a strategy that relies so heavily on a relatively quick solution to the final disposal of ILW and HLW.

Low-level waste

But not only is there uncertainty over the disposal of ILW and HLW, the country’s low-level waste (LLW) repository at Drigg, near the Sellafield site, has insufficient capacity. It is estimated that around 2 million cubic metres of LLW will have been generated by the end of the NDA’s decommissioning and cleanup programme, in addition to an estimated 20 million m3 of contaminated land at Sellafield. Alternative disposal options will, therefore, be required to deal with future arisings of LLW.

The UK’s Environment Agency (EA) is carrying out a public consultation and review of the LLW repository at Drigg. The review, which is expected to conclude by summer 2006, follows the EA’s assessment of BNFL’s 2002 post-closure safety case and 2002 operational environmental safety case for Drigg. In its assessment, the EA stated that the 2002 safety cases “fail to make an adequate or robust argument for continued disposals of LLW because:

  • Estimates of doses and risks from existing disposals to members of the public in the future significantly exceed current regulatory targets.
  • BNFL indicates that the LLW repository is likely to be destroyed by coastal erosion in 500 to 5000 years.”
The LLW disposal at Drigg could therefore create undue burdens on future generations, according to the EA.

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The Achilles’ heel of the NDA’s envisaged plan is the question of where to put the waste

Moreover, the EA’s explanatory document for the public consultation states: “We note that the volume of LLW that will be produced in the UK during nuclear power plant decommissioning is likely to far exceed the capacity of the LLW repository, and that the results of BNG studies may reduce the capacity further. There is an urgent need, therefore, to identify the most appropriate national strategy for the future management of the UK’s LLW, including the consideration of the possible need for one or more alternative disposal sites.”

For the time being, the final destination of much of the LLW arising from future cleanup activities is unknown. The only exception is the Dounreay site in Scotland, where there are now plans to develop a LLW disposal facility at the site, following the Scottish Environment Protection Agency ruling last year to not allow further consignments of LLW from Dounreay to be sent to Drigg.

COMPETITION TIME

When the NDA assumed responsibility for the UKAEA’s and BNFL’s former sites on 1 April this year, operations and cleanup contracts were given to the incumbent site operators, namely UKAEA, BNG, and Westinghouse. These initial contracts are for an initial period of two years. A secondary period, varying from one year to three years, may be awarded beyond the initial period. In line with government targets, the NDA plans to open up the management of all of its sites to competition, which it believes will stimulate improved performance and bring in new ideas and experience.

The NDA intends to launch competition for Drigg and the proposed LLW facility at Dounreay (as one package of work) in April 2006. According to the proposed schedule, the contract would be awarded at the end of 2006 with the contractor assuming responsibility during the 2007-8 financial year.

Competitions for nine Magnox sites, split into two packages, would take place in 2007. One package consists of: Berkeley, Bradwell, Hinkley Point A, Dungeness A and Sizewell A; the other: Chapelcross, Trawsfynydd, Hunterston A and, possibly, Calder Hall, depending on whether the NDA decides to ‘split’ it from the Sellafield site.

The following year, in 2008, the NDA would compete Dounreay (excluding the LLW facility), and – as one package – Harwell and Winfrith.

The Sellafield site is extremely complex and accounts for 60% of the total financial value of the UK cleanup market. The NDA proposes to break up the site into smaller ‘parcels’, but notes it is not possible to do this at present due to the interrelationships between the various facilities. On the other hand, there could be advantages in integrating the Windscale site with Sellafield and competing both as a single package. The NDA aims to begin the competition process for the site in 2009.

The contract for one package consisting of the Oldbury and Wylfa Magnox stations (which are due to continue generating to 2008 and 2010, respectively), would be awarded in 2012.

The future of the remaining sites – Culham, Springfields and Capenhurst – will be considered at a later date.

RISING COSTS

The total estimated lifecycle undiscounted cost of operations, decommissioning and cleanup is now estimated at £56 billion ($101 billion), up from the 2002 estimate of £48 billion. Cleaver said that he expects this figure to increase in the short term. “That’s been the experience elsewhere where this approach has been taken,” he said.

The reasons for the expected increase are, according to NDA chief executive Ian Roxburgh, that, firstly, it takes several years to produce these estimates, and secondly, as one looks deeper into the extent of the liabilities, the more one is likely to find. After about five years from the initial estimate, costs begin to come down as innovative cleanup methods are applied. “So our optimistic hope is, that we’ll plateau – as with the experience of the USA – in about five years, we’ll apply innovation, and then hopefully we’ll see our costs start to come down again,” he said.

Another consideration that would lead to a large increase in the cleanup costs is whether to reclassify the UK’s plutonium stock as waste – an idea put forward in the draft strategy. NDA engineering director Richard Waite said these additional costs would be in the region of £5-10 billion.

Roxburgh added that it was not possible to give a more accurate estimate because there is no single best practice technology to immobilise plutonium. “We’re going to actually have to get our minds around what is practical, and once we know what is practical we need to decide if that’s politically acceptable and then of course we need to put a price to it. So we’re not there yet,” he said.

On the other hand, a decision to classify plutonium as nuclear fuel would be equally problematic. “If we’re to contemplate using the existing stockpile of plutonium and uranium products of reprocessing, then the plant that was designed to turn those products of reprocessing into new MOX fuel – the SMP plant – needs to function properly,” Roxburgh said, adding: “It is not operating as originally envisaged.” He said current plans for the Sellafield MOX Plant (SMP) were to produce up to 25t over the next 18 months. Following this period, “the hope is that the plant can get to nearer 40t a year, at which point it becomes commercially viable in terms of its own running costs. But that outcome is as yet by no means certain.” Even if the government does decide to use the UK’s plutonium in the manufacture of MOX fuel, this would mean that the country would have to commit itself to building a generation of MOX-burning reactors – clearly, this in itself would be a highly controversial decision.

In the final analysis, however, the NDA can only put forward its recommendations to the government on such key issues. Ultimately, the NDA does not have the power to decide, for example, on the fate of the Thorp or SMP facilities. This, along with decisions concerning what to do with the waste arising from cleanup operations, lies in the hands of an organisation that is not well known for taking bold decisions regarding the nuclear industry: the current UK government.


Author Info:

The full draft strategy for consultation is available on the NDA’s website (see link below). The consultation period finishes on 11 November 2005.

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A fine old mess to sort out

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The Achilles’ heel of the NDA’s envisaged plan is the question of where to put the waste





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