RADIOACTIVE PORRIDGE IN WASTE SHAFT
It has been revealed that some of the material used to case plutonium and uranium dumped in the waste shaft at Dounreay will have disintegrated. Some of the nuclear waste was encased using polyfilla or plaster of paris. This may have disintegrated over the years. In a report into the shaft experts felt that where the nuclear waste was cased in cement the packaging was probably stable, but if they were in plaster, this may not be the case.
The authors of the report discovered that most of the records detailing what had been dumped had been lost. In many cases nuclear materials were thrown into the pit without any record being taken in the first place. The report estimates that there may be around 4 kg of plutonium and 98.5 kgs of Uranium 235 in the shaft, along with a dangerous cocktail including sodium and potassium.
The potential for a major accident is very real. On 10th May 1977 there was an explosion at the top of the shaft which was strong enough to blow off the 12 ton concrete lid at the top. This scattered nuclear material around Dounreay. The operators of the site concealed the true extent of this accident from the public for years. They even held back information from the Committee on the Medical Aspects of Radiation (COMARE), when they investigated a cluster of cases of leukaemia around the plant.