7.6 CERTIFICATION 7.6.1 Introduction This section was originally intended to be a Chapter containing the island-by-island certificates of radiological condition prepared by DOE at the end of cleanup. However, the requirement that DOE provide DNA with island certificates at the completion of cleanup prompted early distribution of these documents (Enewetak Radiological Support Project, Island Certifications, March, 1980 reproduced in the microfiche). Rather than reproduce all 43 certificates (totalling 92 pages) only two have been included here to illustrate the two general formats utilized. certificates was made to concerned offices of participating agencies. Distribution of the All of the information contained in the individual certification documents is incorporated in this report. The characterizations by island maximum and average concentrations of transuranies appear in Tables 7-3 and 7-5. Statements about special considerations summarize materials presented in Chapters 6 and 7 and appearonly for islands Irene, Janet, Sally, Ursula and Yvonne. The certificates for islands Belle, with no special considerations, and Sally, with special considerations, are reproduced in Figures 7-112 and 7-113. 7.6.2 Post Certification Actions The rehabilitation phase of the Enewetak Cleanup Project was begun in June 1978, and conducted concurrently over the last 2] months of cleanup. With completion of debris cleanup and island characterization in the summer of 1979, rehabilitation effort was stepped up and directed toward planting of coconut seedlings on selected islands in the northeast segment of the atoll. By 15 March 1980, planting of 10,690 seedlings was completed on the northeast islands of Olive, Pearl, Sally, Tilda, Ursula, and Vera. (Coconut seedlings and cuttings of breadfruit and pandanus were planted on southern islands Bruce, David, Elmer and Fred; however, these islands were of lessér radiological concern than the northeast islands, so are not included in the discussion that follows.) Preparation for planting of the northeast islands included clearing, grading, and leveling. These tasks were accomplished by bulldozing all brush to the seaward side of the island, then grading and leveling only as required to achieve a relatively uniform surface. Hummocks and hollows were not entirely leveled, but enough soil was moved to create a different surface than existed at the time radiological characterization measurements were made. Analytical results of soil samples collected from various depths for both the TRU and FPDB programs; in situ gamma measurements made in connection with brush removal experiments on Janet, Pearl and Sally; and comparison of data related to soil disturbance due to lane clearing on several islands, all support the belief that the soil surface at planting time contained lower concentrations of radionuclides than were measured during characterization. The reduction would be attributed to vertical mixing and horizontal transport with no net change in total inventory. A fraction, perhaps up to 10 percent, of the total soil radioisotope inventory has been relocated to the oceanside beach in the native vegetation cleared prior to planting. This fraction may represent a significant portion of the soluble radionuclides. Future measurements should provide additional information on how effective vegetation removal has been in relocating some of the radionuclides available to food crops. In conclusion, researchers should not expect future in situ gamma measurements or soil analyses to yield the same results as reported herein for the northeast islands where coconuts have been planted. The average radionuclide concentration should be lower (near the surface) because of the mixing inherent in grading and leveling. Future research and measurement programs should provide more information on the effect of clearing and planting on the distribution and availability of radionuclides to food plants. 344