AOLBL4 January 5, 1979 A Mr. Joe Deal Division of Operational and Environmental Safety Department of Energy Washington, D.C, 20545 Dear Joe: In your teletype of November 29 to Mahlon Gates (R291515Z Nov. 78) and confirmed by your direct request at our meeting in Germantown on December 13, 1978, we have been asked to supply the final radiological dose assessment at Enewetak Atoll after the conciusion of the clean-up activities. The Nevada Operations Office was at tne same time asked to suppty a sample collection and analytical program to supply the data base for the assessment. I understand this assessment is to be part of the verification and certification of clean-up at the atoll. The final dose assessment, as indicated by HQ, must now include an assessment of the potential doses due to 137Cs and 9°Sr as well as the transuranics. We are willing to assume this responsibility but several points need clarification: A. Subsistence crops are essentially unavailable jn tne northern part of Enewetak Atoll. As a result the final dose assessment will be primarily predicated on concentration ratios (defined as pCi/g in the plant fruit/ pCi/g in the soil for !3% Cs, 398Sr, Pu and Am) developed from our research program on Engebi (Enewetak Atol]) and Eneu Islands (Bikini Atoll). Current and future radionuclide concentrations in the soil throughout the denth of the root zone are required to produce this evaluation. Radionuclide data in surface soils are required to evaluate the resuspension patnway. Other than the transuranics, data for other radionuclides are not available. It is therefore necessary to develop a post clean-up data base which delineates the radionuclide soil concentration as a function of depth in order to complete a post clean-up assessment. B. We have as yet not received official taskina to provide the C. This assessment will have to be done in conjunction with the final dose assessment. This | feel is essential the critical nature of this final assessment. in view of pending assessment of Eneu Island at Bikini Atoll and the a 2 various assessments associated with the recently completed multi-atoll survey to which we are already committed. BEST COPY AVAILABLE