“the main contamination is picked up, on the leading edges andthe oil cooler intake, Q: Will you be able to correlate aircraft and surface water readings? A: We know what we ran into on CASTIE. The lowest level we could read on the surface was one mr/hr. We want to be able to get data with sensitivity below this and, on this basis, we added shielding for the WIGWAM Operation where it turned out it wasn't necessary. We hoped it would increase this factor by a factor of five or six. We also hope to be very careful in flying. Thank you. Project 2.6.5 = Land Fallout Studies - M. Morgenthau — CRL Project 2.6.5 title is "Land Fallout Studies". The title indicates this process will emphasize collection on land spaces and it's being supplemented by information collected by all other fallout projects. The objective of this process is to prepare isodose contours based on the dose rate data obtained by this process in the atoll area-also from the rad-safe data, and also other projects. This project will collect samples and obtain characteristics of particles in order to help the picture, and to see what type of model is really the correct one. Time of arrival data and rate of arrival of fallout will be measured. Radiochemical Measurements will be made in order to develop fireball models. We also have been trying to determine the arrival of the base surge and the rising of the base surge and if it contains activity. Project 2.6.5 will participate in Cherokee, Zuni and one water shot - probably Flathead. Of course on Navajo it is expected that most of the islands will be flooded. Operationally this project will implement 13 island bases in the Bikini Atoll. At these stations we will have intermittent fallout collectors which will collect samples at five minute intermittent intervals and 30 minute intervals, for a total of 11 hours. We also will have total fallout collectors which will open at the time of the shot and will remain open for 11 hours and then close. Furthermore, the time of arrival detectors and the station monitors will run for two days to be sure that all the fallout will have come down. We expect Signal Corps to furnish on these stations dose-rate meters to record the dose-rate accumulated. This project will also have two total fallout collectors at far distant stations, at Kusaie and Rongerik. In order to correlate with NRDL, we plan to have fallout collecters on the YAGs and the LST, In order to get dose-rate we plan to instrument two helicopters; probably Rad-Safe helicopters. Similiarly to what was done in TEAPOT, the helicopters will fly over the island at 1,000' and a probe will be lowered dow to the island, a microswitch will indicate when the probe is 3' above the surface and readings will be taken in the helicopter. These readings will be as early as possible,and will be repeated at subsequent times to get actual field decay dosages. Construction requirements have been submitted. 28 people in the FA. Any questions? We will have approximately Q: Will these helicopter readings be accurate? A: A few times they have been able to do it and obtain the altitude pretty well COPIED/DOE LANL RC : eames