pee nspaneeeentarent ae mn ee ee oe ctiins tome allie Ae HEADQUARTERS JOINT TASS FORCE SVEN Sen, - APO 187 (HOW), c/o Postraster San Francisco, Cetitorate BEST COP’Y AVAILABLE? April 1954 . an MEMORANDUM FOR RECORD SUBTEXT< BRAVO Shot, Operation CASTLE 2. - PURPCSZ: To make a matt _ 7 record operational as- pects that were considered prior to BRAVO event of Operation CASTLE ard to analyze the resultant situation in light of available pre-shot and post-shot inforzetion. 26 GENERAL INFORMATION: Operation CASTLE is plenned to consist of a series of seven detonations at the Pacific rroving Grounds, which encompasses Eniwetok and Bikini Atolls. S3Ravo is the code neme that was given the firing of the first device, SHEEP, at 0645 MW on 1 Merch 1954, off Namu Island, Bikini Atoll. Subsequent to BRAVO detonation radioactive debris fell on certain inhabited etolis of the northern harshall Islands. Radiation intensities rose to levels sufficient to warrant eva- cuation of four atolls and ell personned were removed from these -atolls to Ewajalein in accordance with the operational emergency plan of JIF S=VEN. are indicated below: . ATOLL Areas evacuated and ganza dosages received POPULATION DISTANCE FRO DOSES RECEIVED GROURD_ZsRO Allinginae Rongelap .- Rongerik Utirie 17 79 eo 8 (computed) 82 100 WS 100-130 R (computed) 270 Ni 17 B (computed) 22 <1 j§$(185MM | 40-98 R (film dadge) (#) 28 Amexhean Service’personnel; 25 USAF Weather Detachment plus 3 USA Signal Corps personnel. All evacuees are under competent nedical care. SS. PREVICCS ECPERISNCE AND CHARACTERISTICS OF KUCLE DETONATIONS: scadioactive debris is an inrerent charecteristie | : of ell noucleer detonations. It originates from fission frequents adley hy SinisSize LCS ion (cgncelies) ( Gtremtee ‘at pry OCP SD Ceca . Gena | yer ASCHETEA HG C ae af kane WOR nm on epee te SK-270- sacs=. Bee oe