could have modified the distribution of radionuclides, Phase III deals with islands which have been sites for, or very near to, surface ground zeros and/or extensive test activities. Contamination exists in the form of activated metal debris, radioactive waste disposal areas, distributed fallout, and localized plutonium contamination, The survey will also include an estimate of the extent of radioactive scrap metal situated on these islands. Finally, Phase 1V addresses Runit (Yvonne), the most heavily contaminated island. The selection process for survey priorities is based upon insult determination of each island from examination of historical records and current radiological data provided by preliminary surveys of Eniwetok Atoll in July 1971, Mey 1972, and of Runit in duly 1972. Field Meter Survey The survey includes a very detailed examination of the peographicai variability of the gamma exposure rate in air on each island due to the gamma rays of greater than LOO Kev emitted by radionuclides deposited in the soil, These nuclides are primarily fission and neutron activation products, The Baird~Atomic scintillation instrument, which utilizes a i" x 1" Nal crystal, will be used to make these measurements. Similarly, the flux of gamma rays of energies less than 100 Kev due to e324 and 2M la will be measured by the FIDLER, This instrument consists of a 1/8" thick x 5" diameter Nal crystal connected to a rate meter. The geographical variation of these measurements will cnable the survey teams to locate the areas contaninated with radtoactivity where soil samples may be collected for laboratory analysis to determine the concentrations of specific radionuclides present. Aerial Radiological Measurements This method has been used by EG&G, Inc. for several years for rapidly and economically surveying large land arees for radioactive deposition and for the location of lost radioactive sources. The data provided by such a survey will be extremely valuable in guiding the field survey teams in the conduct of their surveys. Jt will greatly reduce the possibility of the survey teams missing contaminated areas and at the sare time increase their efficiency by eliminating their need to extensively survey unconiesinated areas. The EG&G airbcrne radiation detection system that we propose to utilize dg -12-