y 409834 ee a< Battelle Internal Distribution Pacific Northwest Laboratories April 18, 1978 To Bill Bair From Dick Gilbert oeohFES Subject Comments on "Assessment of Potential Doses to Populations From the Transuranic Radionuclides at Enewetak Atoll" by 4. L. Robison, W. A. Phillips and V. E. Noshkin. i Ls lands \ lola nw i ™ In my view the subject manuscript suffers primarily from an inadequate “| data base upon which to base dose estimates. = to resuspension and fruit (particularly coconut). az| from fish collected in 1976 are substantially lower than those from fish £ Samples obtained during the 1972-73 Enewetak survey, casting doubt on the \ 5 6°5 COLLECTION Marshal 2 ‘ 60X No. PN N L REPOSITORY R Date BD y r e Project Numb Little data exist with regard utility of the 1976 data used in the present paper. Transuranic concentrations No direct estimates of drinking water concentrations are available for Enewetak. A ratio estimate - obtained using Pu cistern water concentrations from Bikini is used instead. 3 Proposed EPA guidelines are written with reference to the top 1 cm of soil, whereas the present paper considers hypothetical surface soil in the 0-3 cm zone. It’s possible, perhaps likely, that dose estimates based Finally, if this paper is to be used to guide the cleanup effort, it would seem important to base dose predictions on actual soil concentrations presently existing on islands or on anticipated levels after the cleanup has been completed. we This paper relies on purely hypothetical soil concentrations, which, while wa wT Reviewed by,ZA Date LLGG2. DOCUMENT DUES NOI CONTAIN ECI on the 0-3 cm zone could be less than if based on O-1 cm deep samples. showing how dose estimates vary with soil concentration, may not adequately reflect actual soil concentrations. Average soil concentrations for trans- uranics over 1/4 or 1/2 hectare areas on most Enewetak islands based on IMP readings and soil samples are currently available. For each island these averages could be used to obtain dose estimates more closely tied to actual conditions than tne hypothetical averages used in this paper. In what follows I offer some suggestions for improving the manuscript. -1) References should be given relative to the Pu to 24) am ratio of 2 to 1, and the root zone soil concentration (last paragraph, page 3). Also, the Stuart reference (page 5) is not given.