HEADQUARTERS TASK UNIT 13 Task Group 7.2 ™ APO 187 (HOW) P.O. Box & c/o Postzastor San Francisco, California TU-13-54-375 SUBJECT: 1, (¢ 12 March 1954 a f p! © Radiological Survoy of Dorwnvdind Atolls Contaminated by BRAVO Acknowledgement The members of the survey tcam wish to express their appreciatio to * Captain, officers and members of the crow of the USS NICHOLAS (DDE 449) for the assistance and cooperation in conducting tho survoy horcin roportcd, Captain Elliot turned over all possible facilitics of his ship in order to assist in th survey. LT Frink, tho Exccutivo Officcr, organized all the oporations of the boat parties, and it was only through his personal dircction and participation that it was possiblo to carry out the small boat survoys under extremly diffic caditions, Sinee most of the lagoon waters wero not navigable by a DDE, it wa: necessary to make long boat trips in high soas and land on tricky copal reefs, That it was possible to mako, without mishap, a detailed survey of fivo widely, scparatcd atolls in the courso of three days with only ‘two boats was largely du to his efforts, 2. Introduction + _ Tho BRAVO Shot contaminated a number of atolls in gervrally castward ... _Gireetion from Bikini to such an axtent tmt it became necessary to cvacuate th native populations from Rongelap, Alinginac_ and Utirik Atolls and the military persgnnel on Rongerik Atoll, Following this cvacuation CJTF SEVEN organized tt subject detailcd radiological survey of tho atolls to tho castward of Bikini (Ref. CJTF SEVEN Eniwctok 060400Z), the following purposcs: a The data from. this survoy wore required fe The evaluation of the radiation effects on evacuccs. b. The estimation of tho clapsed time before reoccupancy. c. The cstimation of tho residual radiation effects of large yiclds surface dctonations. In connection with this survey, tcams from various Task Groups and Mr, Wilds, Trust Territory Representative, returned to the atolls to secure the evacuated habitations, servico military equipment , and obtain documentary phote graphy. 3. Operational Schedulo 8 March — 0800 TilS DOCUMENT COsSISTS ox__£Z_PAGELS) nelopSScanes, Seues_ SAD- 213 -SY-3E Survoy team rendozvous aboard USS NICHOLAS (DDE 449) in Rongelap Lagoon. . a .