A Spanish research centre specialising in renewable energy and environmental protection is engaged in a clean-up operation after nuclear waste was found in its own backyard.
The Centre for Energy, Environmental and Technological Research (CIEMAT) has detected radium and traces of americium and plutonium buried in a patch of land beside its staff football pitch on its Madrid campus, close to Complutense University.
The waste was discovered when the land was examined as preparation for declassifying the area as a nuclear zone.
The amounts found are too small to constitute a public health risk, according to Jose Luis D!az, the CIEMAT's head of safety. "But we are going down deeper to make sure the contamination doesn't extend further," he said.
Spain's Nuclear Safety Council, which is supervising the operation, believes more waste could be unearthed.
The results could shed further light on Spain's nuclear past under Franco.
But the CSN has said it would be premature to link this find to allegations that the regime was trying to build an atomic bomb.
The CIEMAT is the successor organisation to the Nuclear Energy Board that led Spain's nuclear research programme from the early 1950s until the mid- 1970s on this site. The records do not show how the waste came to be there, but the CIEMAT scientists believe building materials from a contaminated laboratory may have been buried on this spot.
"In those days, instruments for measuring radioactivity were just not precise enough to detect very small amounts," Mr D!az said.
What is now the CIEMAT site housed a series of pilot plants for treating nuclear material and developing technology, according to Juan Carlos Lentijo, technical director of radiological protection at the CSN.