CONTAMINATION RELEASE TO THE ENVIRONS (1 REPORT)

Daily check of 325 stack filters on 5/9/66 revealed contamination released to the atmosphere within the operating area. Investigation indicated that about 0.4 Ci (mostly Ce-144) had been released as a result of steam jet transfer of some Ce-141-144 from a cask to a storage vault in 325-A. on 5/9/66. A further release of about 0.2 Ci vas indicated by survey of stack filters 5/12/66 following completion ot the transfer. Actions taken include vehicle smears, ground surveys around the 300 area fence line, and smears of the 329 loading dock. Daily check or 325 stack filters on 5-9-66 shoved an increase from about 8000 c/m (GM) Friday afternoon to about 450 mrads/hr (CP) Monday afternoon. Vehicle smears on 4-12 shift 5/9/66, ground surveys around the 300 Area fence line, and smears of the 329 loading dock have not revealed any contamination spread. Inventory in 325A (5/10/66) includes about 3 x 10{sup 6} Ci Ce-141-144 and about 3 x 10{sup 6} Ci Pm-147