A a SUBJECT: , — —— Radicsogical Survey of Dovnwind itolls Contaminated by BRAVO 8 March — 1000 ~ 1800 Two partics in smll boats surveyed living arca on Rongclap Island and castorn half of Rongclap Atoll 9 March — 0700 + 1130 Two partics in smll boats procecded from the D which wes stationcd outside Utirik Atoll and survcycd Utirik and Aon Islands, the main islands of the Atoll 9 March — 1500 ~ 1700 Onc party in a small boat landed on the outer reef of Bikar Island and survoycd the island, the onl large island of Bikar ‘Atoll, 10 March ~ O700 - 1100 Two partics in small boats proceeded from the D which was stationod outsidc Rongcrik Atoll and survey Eniwctak Island (where the Task Force's Units had bee stationed) and the other important islands of the Ato 10 March — 1430 = 1980 Two partios in smll boats proeccdcd fromthe D which was stationed ovtsido Alinginac Atoll and surve: tho inhabited islands of the Atoll,' e 12 March - 0700 = 1400 Onc party in a small boat surveyed the northw. orn islands of Rongclap Atoll and onc party rechcckoca tho Living arcas on Rongelap Isiand and established a -rofcrence lecation for future decay-mcasurcments, 12 March ~- O800 4. Survey tcam arrived Fniwotok Atoll via DDE. The following personnel from tcst projects in TG 7.1, TU 13, scrved as members of the survey tcam: Horbert Scoville, Jr, Richard Rast TU-13 Staff Project 2,1 Richard Soule Projoct 2.5a Walmer Strope Project 6.4 The USS NICHOLS (MDE 449) supplicd boat crows under the direction of LT Cliffo: Frink, Executive Officcr, for surveys. 5. _ conduct Curic Co Instrumntation Radiac sct AN/PDR-39 was sclectcd as the instremcnt to be used in the of the survey. Fivo (5) cach of AN/PDR-39 wero cniibiated with an 80 source twenty-four hours before departure, zcro variation between instrummts ~ any scale. Th: cilibration yiclded : Upon cross checking three of these instrumats, (a point of actual survoy) in a radiaticn ficld of 0.320 rf it was found that all threo instruments gave the same reading. Theso survey meters were subject to prolonged use under adverse condi- tions of dampness (to the point of sca watcr splashing ovor thom), salt deposit and continual rough handling. With onc cxccption, all instrumnts oporatcd cfficicntly for the duration of the opcration. On the final day it was found SOPIEDIDOF 2 LANL RG Pen! _ oe 2