SPECIAL NUCLEAR MATERIALS - URANIUM 235 The quantity of uranium 235 produced during the April-June quarter was approximately the same as in the preceding quarter, and slightly greater than forecast. Fire protection for gaseous diffusion plants. Initial construction contract awards totaling about $7 millon were made for portions of the project to reduce fire hazards in the gaseous diffusion plants. Construction began in June. The project, estimated to cost $26.5 million, covers gaseous diffusion cascades and principal auxiliary facilities at Oak Ridge, Paducah, and Portsmouth. The work includes installation of automatic sprinkling equipment, modification of water supply facilities, and improvement of contro] and fire alarm systems. LITHIUM 6 Production of lithium 6 continued at about the same rate during the April-June quarter and was slightly greater than forecast. FEED MATERIALS Construction of the Weldon Spring feed materials facilities was 99.5 percent complete on June 30. All of the plants were in production. Production operations at the Destrahan Street plant in St. Louis were shut down and the facilities were being placed in standby. The Portsmouth hexafluoride feedplant began production in May and was operated at de- sign capacity during June. (End ofQP section.) on KUCLEAR ACCIDENT AT OAK RIDGE Y-12 PLANT (UNCLASSIFIED) A nuclear accident occurred on June 16 in the weapons fabrication facility of the Y-12 plant at Oak Ridge. A critical mass was formed when a Solution of highly enriched uranium was inadvertently transferred from a container of “always safe” configuration to one not so de- signed. The racioactivity thus released set off the alarm system and the plant was evacuated. Except for the immediate area of the accident, the building was reoccupied within 4 hours. Decontaminatiox was completed and all areas were returned to operation by June 23. Eight empicyees were exposed to radiation. Five were estimated to have received exposures betweex 200 and 320 rad.* The other three received less exposure and showed no incications of radiazion effect. All eight were under continuing observation at the Medical Division Hospital of the Oak Ridge Institute of Nuclear Studies. (End of UNCLASSIFIED section.) DOB ARCHIVES * These five men were released from the hespital on July 30. By this time, more than 6 weeks aher the accident, they had passed through their critical period and were recovering satisfactorily from the zcute phase of ex>osure to this radiation. While there were definite changes in the blood elements of ell five men, there were evidences of recovery of the bone marrow such as to warrant a favorable pregzosis. pene ~~ : Flor be _ n-w ¢ 21¢