during cleanup. Final numbers using the revised conversion factor are the basis for all final tables and isopleths, The second aspect deals with the computation of the standard deviation on some of the ratio of TRU to 24lam. Subsequent to the project, a programming error was discovered that caused the standard deviation to be calculated incorrectly. The standard deviations reported in the following chapter are correct. Appendix B. Additional information concerning this problem is in the preface to The ground zero islands, which are also the islands where cleanup was done, are discussed in Section 7.5. The same maps and information as for other northern islands are included, and in addition there are maps of the pre-cleanup condition, subsurface sampling, and post-cleanup isopleths for 0-40 em average 137Cs and 99Sr activities. All the isopleths were drawn by hand using the final, activity data along with other related knowledge. For example, the activities of TRU, Cs and 99Sr are known to be very low on the beaches, and this information was sometimes used to close an isopleth line. The microfiche of raw data at the back of this report includes pre-cleanup and final post-eleanup surface data, all subsurface data, and ail the data from the Fission Product Data Base Program (FPDB) (see Section 6.11) for all islands. Copies of all Island Certifications also appear in the microfiche; only summary statements from the Certifications are Specimens of two Certification formats are presented in Section 7.6. presented in this Chapter. 7.2 SOUTHERN ISLANDS 7.2.1 David Background Island David (Marshallese: Japtan), an island 32.0 hectares in area, lies immediately north of the Deep Passage in the southeast section of the Atoll. It was the site of a German coconut plantation in the nineteenth century, and some of those trees were still present when the cleanup began. The island was used as a housing area for research animals, as a radio receiver site, and as a recreational area at various times during the nuclear test operations. There were no ground zero sites, no known or suspected burial sites, nor any contaminated materials on David. David received fallout from only three nuclear events and the accumulated H + 1 hour exposure rate was just 1 R/h. After the end of nuclear test operations, a 3,000 square foot building was constructed to house equipment during the time Enewetak Atoll was a missile target area. This building and several other structures remained until the cleanup. Some of them were rehabilitated for use by the driEnewetak. 1972 Survey Results Soil samples were taken at 50 locations on David during the 1972 survey, and a numberof vegetation and animal samples were also taken. Profile samples to 115 em depth were taken at seven locations, and 0-15 em core samples were taken at the other 43. The activities of 137s, 90sr and 239,240py were very low, rarely exceeding 1.0 pCi/g, and tended to be constant or decrease slowly with depth. Tables 7-1, 7-2 and 7-3 give summary results for 0-15 em data on 13%Cs, 90sp and 239,240py, respectively. Characterization Results Soil samples were taken at eight locations during the cleanup using the standard procedure (see Section 4.2.1). The TRU activity was less than 0.5 pCi/g in all the samples, so David met Condition C with no soil removal. No IMP measurements were made on David because the TRU activity was too low for the results to be meaningful No samples were taken for the Fission Product Data Base Program because the 1972 data were sufficient for the dose assessment (see Section 6.11). The island average transuranics value reported in the Certification is 0.2 pCi/gm for surface soil, and the transuranics classification is Residence. 207