, HEADQUARTERS TASK UNIT 13 oi Task Group 7.1 APO 187 (HOW P.O. Box 8 Ky AS : c/o Postmstor Sec Pranciseo w“liforrta TU=13—54—375 SUBJECT: t 32 Qe © J) =, | w yy — oy an Ur, Qo] © > re yy aS 1. “BUSEY segam Pe" MATERIAL REMOVED 12 March 1954 Radiological Survoy of Downwiid stalls Contaminatod by BRAVO Acknowlodgcment Tho members of tho survey toam wish to express thoir approciation to + Captain, officers and members of tho crow of the USS NICHOLAS (DHE LL9) for th assistance and cooperation in conducting tho survoy horein roportod, Captain . turned over all possiblo facilitics of his ship in arder to assist in tt survey. LT the Executive Offlecr, organised all tho opcrations of tho boat partios, and it was only through his personal dircection and participation that it was possiblo to carry out the small boat survoys undor oxtromly diffir conditions, Sinco most of tho lagoon mtcrs woro not navigablo by a DDE, it w wy nocossary to makc long boat trips in high scas and land on tricky coral roofs, That it was possiblo to mako, without oishap, a detailed surwy of five widely “aug scparatod atolls in the courso of thro days with only two boats was largoly ch (a ; ga | id eee 33 g Fare MX to his efforts, 2. Introduction Tho BRAVO Shot contaminated a aumbor of atolls in gomrally castward diroction from Bikini to such an axtcnt that it bocame necossary ta ovacuato ti nativo populations from Rongelap, -\linginao and Utirik Atolls and tho military perssnnel on Rongorik Atoll. Following this cvacuation CJTF SEVEN organisod t! subjoct dotatlcd radfological survey of tho atolls to tho oastward of Bikini (Ref. CJTF SEVEN Enimotok 060400Z), the following purposes: ‘h> data from this survoy wero requirod f. a, “he «evaluation of tho radiation offcets on cvacuoos, b, “he csetimation nf the clapsed timbefore rooccupancyes c. Tha costimation of tho rasitual radiation effects of large yiclds surface dotcations, In connoction with this survey, tcams from various Task Groups and Mr. Wilds, Trust Torritory Ropresentativc, rcoturned to tho atolls to sccure tho evacuated habitations, servico oilitary cquipment, and obtain documcntary phot- graphy. 3. Operational Schedule ae 8 March - 0600 AM/ug Survoy toam rondozvous aboard USS NICHOLAS (DDB 449) in Rengelap Lagoon.