British Nuclear Group’s (BNG) lame-duck reprocessing plant THORP is likely to remain closed until March next year. The re-start date, contained in documents received by CORE from BNG under the Freedom of Information Act 2000 (FoIA) is several months later than that suggested by the site’s Managing Director Barry Snelson in June this year when he touted that the plant could re-open around December 2005.
The information, contained in a BNG document titled ‘THORP Clarification Cell Integrated Recovery Plan Detail’ dated June 2005, shows that the Company intends to present its re-start plans to the Nuclear Installations Inspectorate (NII) in December this year and expects to receive NII consent by late January next year. If consent is given, THORP would be brought to a state of ‘operational readiness’ by the end of January, with the first fuel sheared and dissolved in THORP’s Head-End by mid-February and an active re-start of chemical separation in early March.
CORE’s spokesperson Martin Forwood said today “ Even these plans should be viewed with some scepticism as there are still many hurdles – identified as ‘critical milestones’ in the BNG document – to clear before THORP can re-open. The plant has effectively lost a whole year’s business and, with it, the revenues expected by the NDA.”
One major hurdle will be BNG’s receipt of approval from the NDA and NII for the technical fix it plans to apply to the Feed Clarification Cell where the leak of 22 tonnes of dissolved fuel was discovered in April. The fix, for which the costs are currently unknown but likely to be significant, would entail by-passing the leaking pipework and its associated accountancy tank, and operating THORP on the one remaining accountancy tank. Accountancy of the nuclear materials would be carried out in the downstream buffer tanks, providing Euratom inspectors were satisfied. The downside of operating on just one tank is that THORP would be condemned to running at just 50-60% of its design throughput with the Head-End dealing with around 3 tonnes of spent fuel per day rather than the 7 tonnes per day it was designed to handle.
Further information from BNG shows that the leaked liquor, recovered from the Cell floor in June, is still being held in the Cell’s Buffer Storage Tanks and will remain there until THORP re-opens next year. This is a surprising decision given the NII’s concern (revealed in NII documents released to CORE under the FoIA) that ‘the material will have contamination, and past experience on THORP has shown that trace contamination can have devastating effects on long term operation of the chemical separation plant.’ (CORE emphasis). NII further stated that ‘we would consider any proposal to process this liquor as a challenge to the safety case of the plant as it is likely to be outside the specification originally set for the chemical separation design.’