AERIAL PHOTO AND RADIOLOGICAL SURVEY PROGRAM B. RADIOLOGICAL SURVEY The Aerial Radiation Surveys will be carried out by meane of two helicopters SH-3G'’s which will fly multiple miseions from the USS WHEELING atation”sear the atoll or in the lagoons when possible. EG&G will supply the sactentific Flight crews and technical support personnel to operate and maintain the radiation measuring and position measuring equipment. The aerial radiation survey employs large arrays of Nal(Tl) sintillarion detectors mounted on a helicopter platform. Gamma radiation data is accumulated continuously in a 300-channel multichannel analyzer and recorded on magnetic tape ence each second. Position information obtained from a microwave ranging system and « radar altimeter are also recorded on magnetic tape each second. The aircraft is flown at an altitude ef 100' on line spacing of 200'. During the data reduction phase, radiation and position dara are correlated on 4 second-by-second basis and processed in the form of radiation contours overlayed on aerial photographs. The radiation data are processed to provide total gama ray exposute rate and selected isotope (e.g., 241, 1376,, and 60 Co) concentration contours. A total of nine (9) personnel will be required to support the above program for each series.