nuclear-news

Radiation scans unearth first Dounreay particles of 2013

Published: 18/01/2013 11:00 – Updated: 18/01/2013 12:15

A TEAM of Dounreay monitors have recovered the first radioactive particles of 2013 to turn up on Caithness shores.

Site licence company DSRL reported a particle was found on the enclosed foreshore at the site on Wednesday of last week and a further one on Sandside Beach the following day. A spokeswoman yesterday confirmed these were the first particles to be found this year.

The latest particle to wash ashore at Sandside was found during the monthly radiation sweep of the beauty spot. It was found 10 centimetres below the surface and had an activity of 36,000 becquerels (Bq). This places it in the minor (lowest) category in terms of its radioactivity and potential health risks.

It takes to 221 the number of tiny shards of reprocessed reactor fuel recovered since monitoring began at Sandside in 1983.

The Dounreay foreshore particle was detected 11 centimetres below the surface and had an estimated reading of 2,600,000 Bq, putting it in the highest category in terms of activity and potential health risk.

It was the 285th particle found on the foreshore, which is close to the site’s one-time sea discharge outlet — the suspected source of the historic contamination. Much of the foreshore is beyond the perimeter of the licensed nuclear site but is generally inaccessible to the public due to the surrounding terrain.

DSRL has applied to the Scottish Environment Protection Agency (SEPA) to reduce the frequency of monitoring at Sandside from monthly to quarterly. In 2011, 45 particles were detected on the beach with just 12 found last year.

SEPA is currently consulting on whether to sanction the move, given the activity of fuel fragments found to date and the probability of encountering a particle. The proposal comes despite a fuel fragment with an unusual radionuclide composition being detected and recovered from Sandside Bay 11 months ago.

The ratio of beta and gamma radiation is usually one to one but this particle had a ratio of one to 4062. The DSRL spokeswoman said further lab tests are being carried out.

Only three radioactive particles have been found at other beaches in Caithness — two at Murkle and one at Dunnet.

Murkle is only one of two beaches in the report recommended to have more monitoring — it is proposed to have annual sweeps, compared to the six surveys it has had in the last 12 years.

Despite no radioactive particles having been found at Crosskirk beach, SEPA also recommends an annual scan would be desirable as fuel fragments have been found in offshore sediments near the area.

The SEPA report stated monitoring is no longer required at Brims Ness, Scrabster, Thurso and Peedie beaches. Melvich is in line for monitoring once every five years, where models of particle movement to the west of Dounreay have indicated some particles may move past Red Point.

Fragments of irradiated nuclear fuel were first detected on the Dounreay site coastal strip in 1983 and on the beach at Sandside in 1984.

http://www.johnogroat-journal.co.uk/News/Radiation-scans-unearth-first-Dounreay-particles-of-2013-17012013.htm

February 12, 2013 - Posted by arclight2011 | Uncategorized