SELLAFIELD radioactive waste could leak in as little as 40 years from the proposed Nirex disposal site in west Cumbria, a team of geologists from the University of Glasgow has warned.
The risk of death from this leakage could be eight times the British government's safety limit, Dr Stuart Haszeldine, senior lecturer in geology at the university, has claimed. Emissions of radioactive chlorine and iodine could rise from tunnels and shafts which the promoter, UK Nirex Ltd, proposes to excavate in the first phase of its planned radioactive waste repository, he said.
Dr Haszeldine, who was in Dublin recently, is one of a team, of 14 Scottish scientists who have published a report identifying fundamental flaws in the dump site. The controversial plans for the waste site prompted a 66 day planning inquiry, held from September 1995 to February 1996, at which the Government was represented as an objector.
The report of the inquiry was submitted to the British Environment Secretary, Mr John Gummer, last month. At the inquiry, which was attended by the Minister of State for Energy, Mr Emmet Stagg, the Government signalled that it might take legal action if initial rock testing by Nirex was approved by the British Environment Secretary. It also lodged a formal complaint with the European Commission, claiming Nirex failed to comply with the EU directive on environmental impact assessment by not disclosing what alternative sites were examined.
The Scottish geologists claim that Nirex has been aware of the potential hazards for the last two years. A report written for the company in early 1994 simulated a leakage of radioactive waters, which would be caused by the construction methods for tunnelling it intends to employ.
In July 1996, a British government watchdog, the radioactive waste management advisory committee, also warned that these access shafts could form a main route for radionudid emissions, the scientist's haven said.
Dr David Smythe, professor of geophysics at the University of Glasgow, said the problem wash more fundamental than Nirex had appreciated. "Everyone knows that the twice daily ocean tides are caused by the gravitational pull of the moon. What is not so widely known is that the solid's earth also moves up and down due to the same forces," he said.
During its submissions to the inquiry, Nirex gave assurances that construction would be safe. However, Dr Smythe said the size of earth motion was about two feet. Over time, this would work open old cracks around access shafts which Nirex would "claim to have sealed". Radioactive waste heating rock to about 80 C would produce additional cracks.
Generation of gas in the repository could be another unsolved problem. "The combination of these four effects - blasting, tidal "stresses, localised heating and gas, generation - means that it is probably impossible to seal the shafts with any known technology," Dr Smythe said.
British Nuclear Fuels Ltd, which has charged Nirex with developing the disposal site, was unavailable for comment yesterday.
