TESTS are being carried out to determine the potential hazard of what is believed to be the most radioactive particle ever found on a public beach near the Dounreay nuclear power plant in Caithness.
Initial laboratory analysis, carried out at Dounreay, has already shown that the “significant” particle has an estimated radioactivity of up to two mega-Becquerels – a level that could cause potentially serious health effects.
The radioactive hotspot was discovered at Sandside beach, two miles west of the redundant nuclear power facility.
A spokesman for Dounreay Site Restoration Ltd (DSRL), the company responsible for the closure programme at the former fast-reactor research and development centre, said: “The particle was detected in the water’s edge at Sandside.
“Checks carried out on the beach indicated that the particle had higher than normal beta dose rate.
“Initial analysis carried out at Dounreay showed low caesium-137 content, niobium-94 and a high beta dose rate suspected to be from strontium-90.
“Further non-destructive testing indicated that the estimated radioactivity of the strontium-90 is one to two mega-becquerels, which is equivalent to a ‘significant’ particle.
“If confirmed by further analysis, this would be the first ‘significant’ find at Sandside.”
Until now, the most radioactive particle found at Sandside was one discovered in 2007, which had a reading of 500,000 becquerels (Bq). In March 2010, a particle measuring 270,000 Bq was detected.
The spokesman said that the company had informed the Scottish Environment Protection Agency (Sepa) of its initial findings and the need for additional tests to “understand the chemistry of the particle and verify its potential hazard”.
He added: “The particle – detected on 14 February – was the 208th to be recovered from the beach at Sandside.”
“Significant” particles are classed as those with a radioactivity greater than a million Bq of caesium 137.
According to DSRL, such particles could cause visible effects within a few hours if kept in stationary contact with skin and “serious ulceration” after one to two weeks.
Stan Blackley, chief executive of Friends of the Earth Scotland, said the discovery of the latest radioactive hotspot would be of “major concern” to the local community.
“The depressing thing about this is that the more we look at this site, the more and worse we seem to find. We are now several hundred particles down the line and still they keep coming and getting hotter and hotter.”
A spokesman for Sepa said the agency was informed of the detection and recovery of the particle on 14 February.
The particle was found to have a different composition to others previously detected.
He said: “This latest find does not alter Sepa’s view that public access to the beach should continue, given the current level of monitoring carried out and the number of finds to date.”
Work is due to resume in May to clear particles – fragments of irradiated nuclear fuel – from the seabed near the site.
DSRL started work on the seabed in August 2008 and to date, more than 2,000 particles have been recovered from the area.