SLIDE 8 Estimates of airborne activity concentrations. Air activity concentration at Rongelap and Sifo,fsiand wgne tabulated from the meteorology results provided by Peterson for 15,204 i 3fPe8l)- Also, results for air activity concentrations of I and I were estimated from the Bikini Ash composition and tabulated for comparison. Details on this method are given by Lessard (Le84b). The cumilated activity agree somewhat, however the instantaneous airborne activity concentrations do not agree well. In summary, the Peterson approach towards estimating dose to the exposed Marshallese requires further refinement in order to achieve correspondence with all available information regarding external exposure and exposure rate. AIR ACTIVITY CONCENTRATIONS AT RONGELAP Time Post Detonation, Hours 5 7 10 14 17 ot Bq M®? 1981, Peterson ee TTT 1337 7.4 250 15,000 74 ll 1984, Lessard _— i3iy 1337 250 7,400 110,000 3,700 1,100 19 110,000 25,000 330 250 0 0 1,500 , 0 0 igst