Tras, it can be readily understood that readings of two different Gnetrumenta in the sane gamma field aay be different and even two overlapping scales of the same instrunent my not agree. The size of the islands surveyed within the range of this study . apparently does not effect the validity of the sitituds 4o ground etensityconversion curve. Calibration fur the SCINTAMETERS waa perforned over areas of various sizes including both small and large islands in tre Eniwetok and Bitcini atolla. Data from these sewerel locations agreed very closely. Obviously, judgement is needed in evaluating radiation intensity or in terma of potential exposure whether ground measurements Mettawa atl RutatA) res eae intamenannaagece cot easel of the SCINTAMETER at 9,7 Hav," the aver age of gamma fission product activity, ia about 60% greater than both the TIB and the 27¢ internal probe and about 100% greater than the 27C eaternsl prove. sha eased an “ Figure 30, the response Ve EFFECTIVENESS OF MONITCRING PROGRAM The aerial surveys and the automstic monitoring network muat be re- viewed together to analyze the effectiveness of the program properly for they were designed to complement each other. The program was a Practical compromise between two extreme monitoving methods, one be~ ing a monitoring network comprised of stations on each of the islands included in aerial survey patterns (66 in the Marshallese, Carolines, and Marianas} or tho other being daily or more frequent flights over each of the survey Datterne from D ¢ 12 repetitively for a number of days following each event. It is believed that the monitoring program did successfully fulfill the basic requirements of providing timely faliout information con- cerning the Central and Southwest Pacific and of documenting cusmlat ive radiation in those areas. ‘The {sforwation developed by this systen following the BRAVO ourst is an excellent illuatration of ite effectivenesa in performing the former function.* aerial measurevents are the source cf datas *At 15,0 M cn 3 days the autoxsatic monitor on Rongerik, 130 NM Bast of Bikini, went off scale. (Maximus acale reading te 100 ar/ir). This information, received at the Task Force Headquarters aboard the Bates at about 1600 M, was the first indication of excessive fallout outaide of the ships of the Task Force and Bikini atoll itself. A radsafe monitor was sent with a scheduled island resupply flight on the following saorning to clarify the fallout situation which had been indicated by the automatic monitor. At 2000 M on B day, a message to Squadron VP-29 was originated on the Estes requesting the iamediate execution of flight ABLE. The request wa delayed until that hour to diminish the ibility of the survey aircraft paseing thru the radioactive cloud.( Due to communications: difficulties,the nessage did not ° Clear the Estes for about twelve hours after it we originated and the flight. did not leave Kwajalein. until about noon on 8& daysat 1535 & on B41 the first inflight report way received from the aircraft. The report included measurenanta over Ailinginae, Rongelap, and Rongerik. T confirmed neasarements of dangercos radistion aade on Rengerik by the radsafa monitor a few hours earlier. On hig recouendation, evacuation of Rongerik had begun immediately and was complete when the firat inlight message was received. By 2000 M the radiation intensities at all atolls in the ASLE pattern ware known and plans were ‘“rmiated for the evacuation of additional north Marshall atolls. By 2 #5 days, all sur vey patterns had been executed including an faprovised pattern to survey the Gilbert Islands and the extent and severity of contaminstion In the Pacific were clearly defined, . -51-S0-