A leading engineer said today the chronic leakages and routine discharges of radioactive material from Sellafield are not a health hazard to Irish people.
But Mr Frank Turvey, a chartered engineer and a board member of the Radiological Protection Institute of Ireland (RPII), in an article published today, insists Sellafield should still be shut down because of the risk of a serious accident or terrorist attack at the plant.
Mr Turvey said the threat of an accidental or terrorist-initiated attack releasing a large amount of radioactive material was now of more concern than the chronic leakages or discharges from Sellafield.
He said, based on reports from the regulatory organisations, the RPII in Ireland and the Ministry of Agriculture, Fisheries and Food (MAFF) and the Scottish Environmental Protection Agency, there is little if any threat to peoples' health from the discharges from Sellafield.
Contamination of the air mainly by krypton-85 is so small it is difficult to measure. The annual report of the RPII for 2000 concludes that: "The radiation doses due to krypton-85 in the air are very small and do not represent a health hazard".
Contamination of the Irish Sea has greatest effect on people who eat fish caught there. Recent RPII measurements suggest a daily consumption of 200 grammes of fish and a small portion of shell fish will lead to an increase in annual dose of about one micro Sievert (µSv).
To put this in context, Irish people receive an annual dose of 3000 µSv from all sources of radiation. Flying from Dublin to London exposes a passenger to four µSv.
It is the possibility of an accident or attack on the site that concerns Mr Turvey far more than the leakages or discharges.
Particularly vulnerable are the four reactors - the oldest in the world which, unlike modern reactors, have vital components exposed. They contain, as in Chernobyl, thousands of tonnes of highly inflammable graphite.
British Nuclear Fuels has brought forward the shutdown of these reactors to March 2003 because they are no longer economical to operate. When they were first commissioned in 1956 these reactors had a projected lifespan of 25 to 30 years.
Mr Turvey cautioned that the clean-up operation at the site will take years if not decades and must be speeded up.
The high-level radioactive liquid waste storage facility, which contains several thousand tonnes of waste, is of major concern to Mr Turvey. This waste is so radioactive that it will boil - releasing huge amounts of radioactive waste into the atmosphere - unless it is constantly cooled.
These cooling systems have not totally failed to date but the increased probability of a terrorist attack and the prolonged loss of all cooling to the storage tanks creates real concern for inhabitants of the east coast of Ireland, Mr Turvey says.
Sellafield has had a series of safety problems including the Windscale fire in 1957 and an accident in a plutonium-handling compartment in the 1970s.
According to the RPII, a severe accident at the high-level waste tanks would lead to 30 fatal cancers per 50,000 people. While there would be no immediate deaths there would be considerable damage to Ireland's tourism, fishing and agriculture industries.
The UK Nuclear Installations Inspectorate (NII) has insisted that the tonnes of liquid waste be converted into glass blocks that can be cooled by normal air circulation. However, this is a process that will require 15 to 20 years.
With the announcement of the closure of the nuclear reactors, the Government has turned its attention to shutting the mixed oxide (MOX) plant at Sellafield, which was commissioned in December 2001.
The Government went to a UN maritime court last December and lost in a bid to halt the commissioning of the £663 million (€842 million) plant which recycles spent nuclear fuel.
Sellafield's 70 tonnes of plutonium is the biggest stockpile in the world. This weapons-grade material is stored at Sellafield in buildings scarcely more robust that garden sheds, according to the British government's security review board.
In the years since BNFL decided on MOX reprocessing, most nuclear power stations have moved on to using safer and cheaper low-enriched uranium.
Mr Turvey said although the Irish Government's decision to seek the closure of the Sellafield site is mainly a political one; halting all activity on the site is not in Ireland's best interest until waste on the site is made safe.
Cost estimates for clearing up BNFL's nuclear legacy are estimated at £40 billion sterling over 15 to 20 years.
In the midst of this BNFL is haemorrhaging money. Its most recent accounts show record losses of £2.3 billion (€3.6 billion) last year.
Another reason the Irish Government has opposed the MOX plant is because BNFL's main customer is Japan, which means regular shipments of nuclear material through the Irish Sea.
Two BNFL ships, the Pacific Tealand the Pacific Pintail, are due to arrive in the Irish Sea around September 11th. They are returning from Japan because the quality control data was allegedly falsified by BNFL and the Japanese refused to accept the shipment. It is claimed these ships are carrying enough plutonium for 50 atomic bombs.
Yesterday the Government admitted it can do nothing to prevent this shipment passing near Ireland so long as the convoy does not enter Irish territorial waters.
When the Irish Government presses for the closure of the MOX units at Sellafield it is asking BNFL and Britain to write off over £7.6 billion (€12 billion), says Mr Turvey. This is because BNFL is losing an asset. Each gramme of plutonium can generate as mush electricity as a tonne of oil.
The flip-side of this economic argument is that in the event of a high consequence low probability accident or terrorist attack at Sellafield there is no compensation agreement between Ireland and Britain, said Mr Turvey.
The Government does not have third party liability insurance for nuclear energy, mainly because the of the levels of premium required. Therefore if the worst happens, Ireland will have to rely on international law - which most agree would be unable to provide compensation in a reasonable time.
- The full text of Mr Frank Turvey's article can be found in the September issue of the Engineers Journal: www.iei.ie
