Windscale Atom Plant Overheats From Our Special Correspondent Emergency action had to be taken yesterday to cool down one of the great nuclear reactors, which had become grossly overheated, at the United Kingdom Atomic Energy Authority's Windscale plant in Cumberland, where plutonium is produced for military purposes. There are two reactors. At no time was there any risk of an explosion; but workers in the vicinity were told to keep under cover. It was officially stated that there was no injury of any sort to anyone. During the emergency the second reactor was shut down so that its staff could lend aid, but it was not structually affected in any way. The authority stated last night that with the exception of the reactors themselves, " the whole of the Windscale plant area has now returned to normal operation." Safety workers who should have been off duty were called in to the plant. All roads to it were closed to traffic and fire engines stood by. Sir Leonard Owen, Managing Director of the Atomic Energy Authority's industrial group, flew from his headquarters at Risley to Windscale during the day and was satisfied that the situation was " well under control." URANIUM FUEL An official statement issued yesterday, delayed because " their immediate con- cern was naturally to cope with the incident itself," described the accident, which happened on Thursday afternoon. It was discovered then that some of the uranium fuel cartridges in the centre of No. I pile, which was shut down for the routine discharge of spent uranium and for maintenance work, " had become overheated to the point of red heat." The statement continued: " The com- bustion is being held. The staff are now injecting water on it from above and the temperature has started to fall. "Some oxidization of uranium has occurred. The greater part of this has been retained by the filters in the Wind- scale chimneys. A small amount has been distributed over the works site, and in some areas works personnel have, as a precaution, been irstructed to remain under cover. " Health Physics personnel are carry- ing out a continuous check both on the site and in the surrounding district in order to ensure that any increase in the amount of radioactivity would be imme- diately known. There is no evidence of there being any hazard to the public. OUT OF OPERATION "The type of accident which has occurred could only occur in an air- cooled open circuit pile and could not occur at Calder Hall or any of the power stations now under construction for the electricity authorities. At this stage it is not possible to give the cause of the accident. It is likely that the pile will be out of operation for a period of some months." Local reports that the incident began with an explosion which was followed by fire. and that a large amount of radio- activity was released into the air, were categorically denied by the authority last night. On this point the statement said: "It is quite untrue that there was an explosion. In the beginning there was a fire in the sense that the material glowed, but there was no flame. It is untrue to say that a large amount of radioactivity was released; the amount released was not hazardous to the public and what there was. was in fact carried by the wind out to sea." MEN SENT HOME Work in the adjacent Calder HaU power station, which supplies Windscale with electricity, was not affected, 250 people in the chemical plant and the pro- cess plant, and some of the men working in the open on the construction of the Calder Hall B station, were sent home as a precaution. They will start work again on Monday. It was officially explained that the people referred to as instructed to re- main under cover as a precaution went to work, completed their shifts, and moved from building to building during the precautionary period. The only restriction on their movements was the advice not to leave buildings unless it was absolutely necessary. There are 3,000 workers at Windscale. Mr. H. C. Davey, general manager of the plant, paid tribute last night " to the considerable number of people who did valuable work in the emergency." HOODED CHIMNEYS The site at Windscale is dominated by two 400ft. chimneys from the atomic piles. Near the top of each is a hood holding filters to prevent radioactive particles from entering the air. The work of creating plutonium goes on be- hind walls of concrete and stainless steel. While men manipulate the automatic controls, radioactive particles hurl themselves against the barrier. The plant has been in operation for seven years and the accident rate has been well below that for industry in general. Plutonium can be used as a basic mate- rial in nuclear reactors or as the explo- sive in atomic bombs. It leaves Windscale in the form of metaUic billets. By almost completely automatic pro- cesses an extraction plant separates plutonium from uranium irradiated in the two atomic piles at the centre of the 300-acre site. Below the two chimneys is one of the best equipped laboratories in Britain. WINDSCALE ATOM PLANT OVERHEATS EMERGENCY STEPS BRING PILE "WELL UNDER CONTROL" WORKERS ORDERED TO TAKE COVER