Sellafield leak 'would cause no observable health effects in Ireland'

International experts have told the Irish Government that a radioactive leak at the Sellafield nuclear site would cause no observable health effects in the country.

The independent team of nuclear physicists, chemists and engineers used previously secret data from the facility in Cumbria to declare the low risk.

But they found that some severe incidents at Sellafield or the low-level waste repository have the potential to do significant damage to Ireland's tourism, seafood and farming industries because of concerns over radioactivity.

Environment Minister Phil Hogan said vigilance was key.

"My department and others will now study the information in the report in detail and use it to feed it into Government policies relating to Sellafield and nuclear policy in the UK," he said.

"Ireland must continue to be vigilant in relation to Sellafield as work to decommission the site over the lifetime of the Sellafield Plan continues.

"It is critical from an Irish perspective that the UK decommissioning of the site is undertaken safely and in accordance with best international practice."

Possible scenarios examined by the independent risk assessment panel included earthquakes, meteorite strikes, plane crashes, terrorist attacks, explosions, fires, and human error.

They also looked at the very long term and what the impact would be hundreds of years from now from rising seas and severe coastal storms on the waste repository.

It found that currents and sea water would dilute the remains of radioactive materials.

Based on calculations that overestimate the consequences of such a release, the report found the increase in radioactivity levels in seawater would be barely detectable anywhere near the coast of Ireland.

Sellafield is expected to cost at least £67.5bn (€83.4bn) to decommission and clean up.

The site is regarded as the UK's largest and most hazardous nuclear site, storing enough high and intermediate level radioactive waste to fill 27 Olympic-sized swimming pools.

The operators are being prosecuted over allegations that it sent four bags of low-level radioactive waste to a nearby landfill site in Cumbria.

About 240 of Sellafield's 1,400 buildings are nuclear facilities and so far 55 buildings on the site have been decommissioned.

A report by a UK public spending watchdog earlier this month warned that ageing nuclear waste facilities pose significant risks to the population and plans to replace them face considerable uncertainty.

The UK's National Audit Office (NAO) said that for more than 50 years operators failed to plan how to dispose of the radioactive waste.

It found some of the older facilities "deteriorated so much that their contents pose significant risks to people and the environment".

On the dangers to Ireland's tourism, seafood and farming sectors, experts said the likelihood was from less than a 30% chance anytime over the next 100 years for a modest radioactive release to less than a 0.05% chance for a more extreme case with the potential to release materials outside of Sellafield.

"These very rare severe incidents are largely associated with extreme environmental events such as severe earthquakes and very strong winds (greater than 165 mph) or incidents originating outside the Sellafield site that can impact it, such as strikes by meteorites or by aircraft or missile crashes," the report said.

It found lesser incidents are more likely due to equipment failures and human errors.

In one assessment, the experts looked at the release of a portion of the contents of a storage tank containing highly concentrated radioactive material.

It found that some radioactive materials could reach Ireland but at levels far below the dose levels that cause observable damage to health and well below the level of background radiation people normally receive each year.

All other scenarios were deemed to be lower risk.

A plane crash into the LLWR was the only real risk of radioactive material from that site.

Operating since 1959 it is used to dispose of Sellafield's low-level radioactive waste such as clothing, soil, and building rubble.

Experts examining the danger from the overall site built a probabilistic risk assessment (PRA).

An information exchange agreement between the Irish and British governments gave the experts three two-week visits to Sellafield and additional technical information.

The UK did not disclose certain highly sensitive information related to security measures at Sellafield.