Dounreay's nuclear porridge

The shaft at Dounreay in which nuclear waste was dumped may be full of a radioactive mixture with the consistency of porridge. It has been revealed that drums put into the shaft were full of a radioactive liquid, including plutonium, mixed with plaster of paris or polyfilla. Initially cement had been used for this purpose. The polyfilla replacement may well have disintigrated in the water logged shaft.

A recent attempt to work out what is down the shaft has run into serious problems. Most of the records detailing what was dumped have been lost. In some cases material was dumped without any record being made in the first place.

Scientists at the plant tipped boron mixed with pyrex glass down the shaft in December 1968 in an attempt to soak up some of the radiation. They were concerned that there was enough plutonium and uranium debris in the pit to cause an uncontrollable chain reaction.