British Nuclear Group (BNG) at Sellafield who operate the Thermal Oxide Reprocessing Plant (THORP) under contract to the Nuclear Decommissioning Authority (NDA) has admitted that there will be yet a further delay to the return to full operation of the plant.
Following recent confirmation from BNG that, although receiving consent to restart operations from the Nuclear Installations Inspectorate (NII) on the 10th January this year, THORP was unlikely to re-open until April when checks on downstream equipment associated with the liquid high level wastes were expected to have been satisfactorily completed. BNG’s latest Sellafield Newsletter (28th February) has conceded that, as these equipment checks are not now expected to be completed until ‘the middle of 2007’ there will be no prospect of THORP commencing full operation until then.
The downstream equipment responsible for the further delay is Evaporator C in which the highly active liquors from reprocessing are processed prior to storage in the High Level Waste tanks. BNG’s reasons for the belated investigation of the Evaporator remain obscure and conflicting. Its claim in the 28th February Sellafield Newsletter that ‘we have had no problems with Evaporator C’ will clearly raise questions as to why, with NII consent already gained, checks that would inevitably lead to further costly delays and frustration are either necessary at all or are only being carried out at this very late stage of the plant’s extended closure.
The re-opening of THORP, closed since the INES Level 3 spillage accident in April 2005, was originally projected by BNG to restart in December 2005 – a date subsequently advanced numerous times as a result of the complexity of the mopping-up work after the accident, the modifications to the damaged Cell where 83,000 litres of dissolved reactor fuel leaked undetected over an eight month period, and the securing of regulatory consent at every stage.
This latest delay will be of increasing concern to the NDA who, as owners of THORP, are already counting the costs of the loss of two years reprocessing revenue currently put conservatively at around £50M. It will also trigger fresh alarm bells with Overseas customers already angered by delays to their contracts (at least 5 years late) and at BNG’s inept handling of THORP. The extra delay will also increase the pressure on the availability at Sellafield of sufficient pond storage space to accommodate the weekly import of spent AGR fuel from British Energy’s (BE) power stations. With no reprocessing of BE or other fuel for what is now likely to be 30 months, the normal ’12 months spare pond capacity’ reserved for AGR fuel, will already be at a premium and the unrestricted operation of those power stations increasingly compromised.
In the NDA’s Lifetime Plan for Sellafield, THORP operations are due to finish in March 2011. With some 4000 tonnes of contracted fuel (Overseas and BE) still to be reprocessed by that date, THORP faces the impossible challenge of reprocessing at a rate of well over 1000 tonnes per year if the contracts are to be fulfilled. The plant has averaged around 550 tonnes per year since it commenced operations in 1994. The futility of the situation has lead many to call for THORP’s immediate and permanent closure, including demands from the Norwegian and Irish Governments.