DEPARTMENT OF THE NAVY OFFICE OF THE CHIEF OF NAVAL OPERATIONS WASHINGTON. D.C. 20350 1% REPLY REFER TS B December 1980 wet . MEMORANDUM FOR THE RECORD Subj: 1. Test 410417 Radioactive Fallout on Navy Bases in the mMaersnall Islands Radioactive YOKE, rain Operation fell on SANDSTONE. Kwajalein The rain Atoll as a commenced at result 1800 May 1946. The rain-out continued until 0400 on 3 May 1948. Maximum activity observed was 6 to 10 mr/hr. Among the cilities and units at Kwajalein at the time were: Navel Station Kwajalein DET, VPAM=-2 (DMS-37). Harbor at 2. of Ship Kwajalein, Security DET, VPHL-8, NS Detail, VRU-3 In addition, USS 0900 on 3 May 1948. Racioactive Test ROMEO, March 1954 Kwajalein In DET, VR-8& (DMS-37) of 2 The fa- NAS Kwajalein, Service Crafr, DET USS Construction DAVISON on Battalion and entered NS 1509 QUICK Kwajalein fallout occurred on Eniwetok Atoll as a result Operation CASTLE. At approximately 1230 on 29 (54 hours after ROMEO) intensity levels began to riSe. By that evening, readings averaged 5 mr/hr, with a 15 mr/hr maximum on windward surfaces. At that time, no permanent naval bases were located at Eniwetok (the Naval Station at Eniwetok was Closed Boat Unit is on 23 June 1947). However, Pool Detachment, a Detachment were at Eniwetok on 29 March. currently Eniwetok considered Lagoon USS NICHOLAS USS TAWAKONI unit] 1315 a a Naval Shore non=-participant, on Detachment, a of VC-3 and possibly a MATS In addition, LST-1146, which 29 March. Also, was Task anchored Force in ships (DDE-449), USS CURTISS (AV-4), USS SIOUX (ATF-75), (ATF-114), USS GEORGE EASTMAN (YAG~-39), USS LST-762, and USS PC-1546 all entered or were already anchored Lagoon on 29 March. in Eniwetok 3. Radioactive intensities also roSe on Kwajalein as a result of ROMEO. On 31 March 1954, radioactivity levels were recorded at 9 mr/hr maximums on the windward side of tree trunks, 1 to 3 mr/hr average on beaches, and 1 to 4 mr/hr average on the windward side of buildings. The average Kwajalein background prior to 31 March was 0.05 mr/hr. In addition, aircraft on training flights in the local area recorded concentrations of 2U mr/hr on engines. As a precautionary measure, water catch basins were examined and samples of the first taken for analysis. no activity except number run-off of the next Of the five Samples collected, for the one graken from open rain were all indicated storage tank 10 which read 4.85 X 1074 microcuries per milliliter. Kwajalein naval units at the time included Kwajalein Station, Kwajalein MATS Unit, CHB~-4 Kwajalein, and VP-29. BEST COPY AVAILABLE 2 ee a me ee Naval