SOIL outside Harwell laboratories has shown higher-than-expected levels of radioactivity.

Critics of the site's nuclear programme have now called for a detailed ground survey around Harwell International Business Centre.

But the Atomic Energy Authority insisted the samples indicated "very low levels of radiation due to natural uranium".

Harwell's public relations manager Nick Hance said: "There is no risk to public health although where background levels of radioactivity are higher than normal, the decision is sometimes taken to remove the contaminated soil."

The soil samples which were taken from five areas on the south side of the Harwell site - close to the proposed large Chilton Field housing development - are now being examined.investigated to determine what is naturally occurring uranium and whether the contamination could be caused by other forms of radiation.

Mr Hance said higher than normal background levels of radiation often occurred naturally in granite chippings used on roads.

The soil samples were taken as a result of an independent study of radiation levels around the Harwell perimeter fence commissioned by the Vale of White Horse District Council last year.

The study - undertaken by the Scottish Universities Research and Reactor Centre from Glasgow - answered questions arising from a previous aerial gamma survey of the countryside around the former Greenham Common air base in 1996.

Anti-nuclear campaigner Wendy MacLeod-Guilford, of Blewbury Environmental Research Group, repeated calls for a detailed ground survey around Harwell to detect signs of highly radioactive plutonium.

But Mr Hance said: "The recent samples only show very low levels of radio- activity."

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