The first-ever World Nuclear Waste Report (worldnuclearwastereport.org) is a mighty achievement and hopefully future reports will build on the foundations. As a first-of-a-kind report, inevitably there are limitations and omissions (and possibly delays and cost overruns!). Pete Roche expands on the WNWR's section on the UK.
The World Nuclear Waste Report1, published earlier this year doesn't quite give readers a view of the full horror of the radioactive waste mess the UK has got itself into.
Waste from new reactors
The report says the independent Committee on Radioactive Waste Management (CoRWM) reported in 2006 in favour of Deep Geological Disposal (DGD) for all higher activity waste, but doesn't mention that CoRWM's 2006 report emphasised that its recommendations were directed to "existing and committed waste arisings … New Build wastes would extend the timescales for implementation, possibly for very long, but essentially unknowable, future periods. Further, the political and ethical issues raised by the creation of more wastes are quite different from those relating to committed – and therefore unavoidable – wastes."2
In September 2007 CoRWM re-iterated the point saying: "To justify creating new spent fuel from an ethical point of view, there must be a management solution that is ethically sound, not just least bad. … In short, a solution that is ethically acceptable for dealing with existing spent fuel is not necessarily a solution that would be ethically acceptable for dealing with new or changed materials."3
Sellafield's high-level liquid waste
The report says closure of the Magnox stations and the poor and deteriorating state of Sellafield made it clear by the early 2000s that a more coherent policy and higher expenditures were needed to manage waste in the short- and medium-term. The establishment of setting up the Nuclear Decommissioning Authority (NDA) in 2005 was a recognition that Sellafield was the most problematic UK site, containing a huge range of ex-military and ex civilian buildings and wastes including four so-called Legacy Ponds and Silos, all representing major hazards, as well as being home to virtually all UK spent fuel. But there is no specific mention of the extreme concerns expressed about the liquid High Level Waste tanks, especially after the 2001 terrorist attacks in New York and Washington.
The intensely radioactive liquids known as Highly Active Liquors (HAL) which result from reprocessing spent fuel generate their own heat, so must be stored at Sellafield in special cooling tanks to prevent the waste from boiling. The consequences of a prolonged cooling failure could be 'very severe' leading to boiling after 12 hours, and to the tanks drying out after three days with radioactivity escaping and contaminating the surrounding environment. Consequently, the HLW facility at Sellafield is probably one of the most dangerous nuclear facilities in the world with the potential to at least force the evacuation of much of northern England and southern Scotland, and cause long lasting contamination well beyond the UK.4
The Highly Active Liquor Evaporation and Storage (HALES) area at Sellafield consists of four evaporators A, B, C, the recently commissioned D5, and a number of High Activity Storage Tanks (HASTs). There are 21 tanks, some dating back to the 1950's6, but the number in use has been reducing since 2009 with only around half in use by 2013.7
In the year 2000, the Nuclear Installations Inspectorate (NII) (now part of the Office for Nuclear Regulation ‒ ONR) warned that the High-Level Liquid Waste storage tanks at Sellafield needed to be emptied and the waste solidified "as soon as reasonably practicable", reaching a buffer level by 2015. Any shortfall, it said, would be "publicly unacceptable".8 In January 2001, the NII issued the Sellafield operator (at the time British Nuclear Fuels Ltd BNFL) with a legal requirement to reduce the level of High-Level Liquid Waste down from approximately 1600m3 to a residual or buffer stock of 200m3by 2015.9
Following the 9/11 terrorist attacks a review was undertaken by the Parliamentary Office of Science and Technology (POST) of the impact of similar attacks on vulnerable UK facilities. It found that a terrorist attack on the tanks could require the evacuation of an area between Glasgow and Liverpool, and cause around 2 million fatalities.10 The Massachusetts-based Institute for Resource and Security Studies (IRSS) reported that highly radioactive liquid stored in tanks contained around 2,400 kilograms (kg) of Caesium-137 compared with the 30 kg released during the Chernobyl accident.11
In 2011 the ONR decided to increase the permitted level of HAL stocks to almost three times the limits defined under the earlier legal requirement.12 This increase to the 'buffer level' was to provide Sellafield with "the flexibility to accelerate the hazard reduction". Part of the explanation given for this was that the original legal requirement was set at a time when reprocessing was expected to have been completed by about 2015, at which time a minimal working "buffer stock" level would have been reached. But reprocessing operations had been plagued with problems. THORP is now closed and the Magnox Reprocessing Plant is expected to close in 2020. The 2011 ONR recommendation was that the Steady-State Specification should be set at 5,500 tonnes uranium (teU).
The Chief Nuclear Inspector reported in October 2019 that stocks of Highly Active Liquor at Sellafield currently amount to around 5,750teU. According to the Inspector stock levels have remained steady for the last few years "due to a number of operational issues, but it is anticipated that HAL stock reduction will now continue".13 5,750teU would be equivalent to around 484 m3 – more than double the buffer stock originally expected to be achieved in 2015 by the NII. (If 19,000 teU is equal to 1,600m3, 5,750 teU = 484m3.)
The World Nuclear Waste Report mentions briefly that "Scotland's policy is different from that of the rest of the UK, and envisages near-surface disposal of all nuclear waste within its borders". The Scottish Government's policy, in fact, only refers to Higher Activity Waste. It says that the long-term management of higher activity radioactive waste should be in near-surface facilities. Facilities should be located as near to the site where the waste is produced as possible. The Scottish Government does not support deep geological disposal of radioactive waste.14
However, since spent fuel is not classified as waste, spent fuel from Scotland's remaining operating reactors is still transported to Sellafield. Nor does the policy apply to LLW or VLLW. Scotland does not have a landfill site for VLLW, or an LLW repository outside of Dounreay, so still sends lower level waste to the Low Level Waste Repository at Drigg in Cumbria and English landfill sites at Clifton Marsh in Lancashire and Augean in Northamptonshire. It also continues to send contaminated metal for decontamination and so-called recycling to the Cycliffe plant at Lillyhall in Cumbria.
Dounreay is hardly covered in the report, although the fact that it is a site for LLW disposal is mentioned, despite it being the site of some of our worst horror stories. Dounreay was the UK's centre of fast reactor research and development between 1955 and 1994 and is now described as Scotland's largest nuclear clean-up and demolition project.
The Dounreay Fast Reactor (DFR) first achieved criticality in 1958, and operated until 1977. Most of the breeder elements were removed soon after, but almost 1,000 were found to be swollen and jammed in place. They were left in place until remotely-operated tools could be developed.15 Recovering the jammed elements began forty years after the reactor closed, and by 2019 half of them were still in place.16 This spent fuel is being transported to Sellafield for reprocessing in the Magnox fuel reprocessing plant but not all of it will arrive before the plant closes in 2020, so arrangements are being made to dry store the remainder at Sellafield.
The Prototype Fast Reactor (PFR) opened in 1974 and closed in 1994. The site also housed a fast reactor reprocessing plant, as well as a research reactor reprocessing plant. Overseas research reactor spent fuel was imported for reprocessing up until 1974 when it stopped because foreign customers were unwilling to take their waste back. Then in 1992 Dounreay re-entered the research reactor spent fuel reprocessing business with spent research reactor fuel imported, mainly from Germany until it was announced in 1998 that Dounreay would not take on any new contracts. Dounreay was also site of a materials test reactor which operated between 1958 and 1969. The Vulcan submarine reactor test facility is also at Dounreay with one reactor in care and maintenance and another in the process of being defueled and spent fuel being dispatched to Sellafield.
In 1958 the Scottish Office authorised use of an underground shaft – built to remove spoil during construction of a sub-sea effluent discharge tunnel – as a disposal facility for intermediate level radioactive waste. More than 11,000 disposals took place between 1959 until 1977, when a chemical explosion occurred and the practice ceased. Decommissioning the 65-metre deep shaft is a major challenge. A second facility, the intermediate-level waste silo, also needs to be emptied. A concrete-lined box built just beneath the surface, it was used to dispose of waste between 1971 and 1998. Work to retrieve waste from the shaft and silo isn't expected to get under way until around 2023. Preparatory and construction work have to be carried out before the waste can be removed.17
Another major problem at Dounreay is the appearance of radioactive particles in the environment. These small fragments of irradiated nuclear fuel have been found on the seabed off Dounreay, on the Dounreay foreshore and on Sandside Beach west of Dounreay, which is open to the public. A fishing ban prohibits the removal of fish, crustaceans and molluscs in an area of 2km (1.2 mile) radius centred on the disused Dounreay discharge point near where the highest density of particles has been detected.18 It will be around 200 years, before the activities of the larger particles, have decayed sufficiently that they can no longer be considered a potential hazard. Particles will keep polluting public beaches for decades to come, and the environment will never be completely cleaned up. Despite assurances that the risk is low of a member of the public coming into contact with a particle which is a serious hazard to health, it is uncertain that this will continue to be the case. Since 1983 almost 500 radioactive particles have been found including more than 200 on the publicly accessible Sandside beach.19
In 2015 new low-level waste vaults at Dounreay started to accept waste.20 This is the only UK low-level waste 'disposal' facility other than the low-level waste repository at Drigg near Sellafield. Previously low-level waste generated at Dounreay had been dumped in a rather haphazard fashion in the low-level waste pits. The current plan is eventually to retrieve the waste from these pits, repackage it and then place it in the new vaults. However, the Scottish Environment Protection Agency (SEPA) has told Dounreay that it has been "non-compliant with regard to its obligation not to allow radioactive substance to contaminate the groundwater near the pits". This may force Dounreay to remove the waste from the pits sooner than originally planned.
Radioactive water is leaking from a nuclear waste storage building as big as 132 double-decker buses at Sellafield. Sellafield Ltd said there is no risk to staff nor the wider community as the water, which covers the solid radioactive waste in the silo, will remain in the ground "for some time". The leak is believed to be originating from the six older compartments of the Magnox Swarf Storage Silo, which has 22 compartments in total. However, it is not known how much water has been lost so far. The majority of the radioactive material stored there is fuel cladding, which Sellafield says has an intermediate level of radioactivity.21
Reprinted from nuClear news, no.120, Dec 2019, http://www.no2nuclearpower.org.uk/wp/wp-content/uploads/2019/12/NuClearN...
1. The World Nuclear Waste Report 2019, Focus Europe, https://worldnuclearwastereport.org/wp-content/themes/wnwr_theme/content...
2. Managing our Radioactive Waste Safely: CoRWM's recommendation to Government, July 2006, para 26, https://assets.publishing.service.gov.uk/government/uploads/system/uploa...
3. Re-iteration of CoRWM's Position on Nuclear New Build, Gordon Mackerron September 2007. Page 3
4. Consequences in Norway after a hypothetical accident at Sellafield, Norwegian Radiation Protection Authority, 25 January 2011, https://www.dsa.no/dav/9d9004bb5b.pdf
5. Sellafield Ltd, 22 Dec 2017, https://www.gov.uk/government/news/d-day-as-evaporator-starts-its-mission
6. HALES – Evaporator D Transition to Normal Operations, ONR, Nov 2018, http://www.onr.org.uk/pars/2019/sellafield-18-026.pdf
7. Bellona, 17 June 2013, https://bellona.org/news/nuclear-issues/nuclear-uk/2013-06-sellafield-de...
8. The Storage of Liquid High Level Waste at BNFL Sellafield, HSE, February 2000, https://webarchive.nationalarchives.gov.uk/20100409182519/http://www.hse...
9. The Storage of Liquid High Level Waste at BNFL, Sellafield, Addendum to 2000 Report, HSE, August 2001, https://webarchive.nationalarchives.gov.uk/20100409182519/http://www.hse...
10. Assessing the risk of terrorist attacks on nuclear facilities, POST Report 222, July 2004. p81, https://researchbriefings.parliament.uk/ResearchBriefing/Summary/POST-Re...
11. Civilian Nuclear Facilities as Weapons for an Enemy, A submission to the House of Commons Defence Committee, Institute for Resource and Security Studies, 3 January 2002, https://irssusa.files.wordpress.com/2013/10/ukdefcttee01_02_000.pdf
12. ONR Project Assessment Report, ONR 2011, http://www.hse.gov.uk/nuclear/halstock-sellafield-par.pdf. Also Guardian, 14 May 2015, https://www.theguardian.com/environment/2015/may/14/sellafield-nuclear-w...
13. Chief Nuclear Inspector's Annual Report on Great Britain's Nuclear Industry, ONR, October 2019, http://www.onr.org.uk/documents/2019/cni-annual-report-1819.pdf
14. Scotland's Higher Activity Radioactive Waste Policy 2011, Scottish Government 2011, https://www.gov.scot/binaries/content/documents/govscot/publications/cor...
15. BBC, 15 Oct 2019, https://www.bbc.co.uk/news/uk-scotland-highlands-islands-50055003
16. Energy Voice 14 Oct 2019, https://www.energyvoice.com/otherenergy/nuclear/209706/half-remainingfue... See here for a short video
17. Press & Journal, 13 Sept 2019, https://www.pressandjournal.co.uk/fp/business/north-ofscotland/1840933/w...
18. Guardian, 21 Sept 2011, https://www.theguardian.com/environment/2011/sep/21/scottish-nuclear-lea...
20. Dounreay, 19 May 2015, https://www.gov.uk/government/news/dounreay-low-level-waste-vaults-begin...
21. Carlisle News and Star, 22 Nov 2019, https://www.newsandstar.co.uk/news/18052479.radioactive-fluid-leaking-silo/