When Shot NECTAR was detonated at 0620 hours on 14 May, seven of the ships were in their assigned operational areas southeast of Enewetak. These were: CURTISS LST-551 SIOUX ESTES NICHOLAS RENSHAW AINSWORTH The EPPERSON and BELLE GROVE were enroute to Ujelang and Rongerik Atolls, respectively. Within several hours after the detonation, all ships that were southeast of Enewetak, except the NICHOLAS, reentered the lagoon; the NICHOLAS did not get back into the lagoon until late afternoon. The EPPERSON returned to Enewetak from Ujelang late in the afternoon on 14 May, while the BELLE GROVE did not return until the morning of 16 May. The BAIROKO had arrived at Enewetak from Bikini during the morning of 15 May. Between 1830-2100 hours on 14 May, light fallout from the NECTAR cloud was experienced on the residence islands of Enewetak. The CURTISS, ESTES, and AINSWORTHhad departed Enewetak for San Francisco, San Diego, and Pear! Harbor, respectively, before the fallout began. The EPPERSON, NICHOLAS, and RENSHAW did not depart the lagoon until approximately 2200 hours enroute to Pearl Harbor and could have experienced the fallout. Similarly, LST-551 and SIOUX remained at, or in the vicinity of, Enewetak until 1@ and 17 May, respectively, and they too, probably received the fallout on 14 May. The LST-551 departed Enewetak for Ponape Atoll while the SIOUX departed for Bikini. As stated earlier, the BAIROKO and BELLE GROVE did not return to Enewetak until 15 and 16 May, respectively, well after the fallout had ceased. The BELLE GROVE departed Enewetak for Bikini on 16 May and the BAIROKO got underway to San Diego on 17 May. 2.2 RADIATION ENVIRONMENTS Extensive radiation intensity readings obtained on How Island (Bikini Atoll) following Shot BRAVO indicated decay rates that varied considerably from traditional t7!-? rule (Reference 11). the Average values for the decay exponent (k) 26