Table 17 represents the exposure rate at each pattern of activity as listed in Table 16 calculated assuming 100% occupancy for Rongelap Atoll, Table 18 presents an estimate of the exposure rate for each age group, weighted by the percent of time spent in each area for inhabitants of Rongelap Atoll based on the Lawrence Livermore lifestyle Model (3,4). Summation of the exposure rates in each area provides the average exposure rates to the Rongelapese. Using the average hourly exposure rates, the long term external dose was calculated. These data, presented in Table 9 for Rongelap Atoll, have been cor- rected for background (terrestrial and cosmic) radiation by using the average exposure rate of Wotje and Ailuk Atolls as a representative sample of the normal (unexposed) Marshall Island environment. We feel that this is a very conservative estimate for Rongelap Atoll since the people rately visit the more heavily contaminated islands in the north, and tend to restrict their “other islands" visits to the southern sector where exposure rates are similar to that on Rongelap Island itself. This observation was supported by an independent living pattern assessment from which data became available in the fall of 1977 (5). Specific living pattern information for Rongelap was obtained on a field trip in October 1977 (5). This information is presented in Table 20, It should be noted that as previously mentioned, the Rongelap "lifestyle" involves very little time away from Rongelap Island where a constant exposure rate-of 7.3 uR/hr is assumed. Revised external dose predictions based on the observed Rongelap living pattern are given in Tables 21, 22 and 23. These doses include corrections for physical decay for 137 Gg and ®9¢o which are responsible for >99% of the total external exposure rate above background. The cesium and cobalt ratios were obtained using the averages of soil sample activities from analyses by BNL (6) and the University of Washington (LRE) (7). It was assumed for this assessment that no radionuclide loss mechanisms are operative other than physical decay. -g-