ite2 Nencennenerne Project 2.65 - Analysis of Fallout and of Ease Surge - M. Morgenthau OBJECTIVES To obtain fallout samples on land and to perform radiophysical and radiochemical measurements on the samples. To prepare dose rate contours of the atoll srea from information gethered by this project, other projects, and RadSafe. To evaluate the role of the base surge in transport of radioactive meterial ESCRIPTICN AND EXPERIMENTAL PROCEDURES Intermittentfellout collectors, (IFC), and gross fallout collectors, (GFC), were installed on islands in the Bikini Atoll and on the YAG's and LST in the expected fallout zone. The IFC timing intervals were one minute, five minutes, or 30 minutes depending on location of the collector. The equipment was in- stalled prior to the shot and was activated by EGG Blue Boxes, Samples to be used for early decay measurements were recovered on D-day and the balance of the samples were recovered on D+l and D+2, helicopter. All of the recovery was made by Wire signals were used to activate the base surge detectors as a warm-up period was required before shot time. Some of the stations also incorporated a tape fallout monitor, (TFM). On D-day, D+l, and D+2, an aerial survey of residual radiation was made over the respective islands by helicopter. The measurements were taken by means Of a probe on a long cable suspended below the hovering helicopter. The positions of the probe were determined by comparison with maps and aerial photographs. Two project personnel were stationed in the Program 2 Control Center to consolidate data from the various projects and to assist the Program Director in maintaining a situation plot. Pacers - Co: Dae LENE RS - 24+ J

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