Field Task Proposal/Agreement: Dose Reassessment for Rongelap and Utirik

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U.& DEPARTMENT OF ENERGY 1. WORK PACKAGE NUMBER 12. TASKNO.,~.R$. ,- 4, PROJEm NO. 5. DATE PREPARED 7. TASK TITLE 8. WORK PACKAGE TITLE Dose Reassessment for Rongelap and Utirik 9, BUDGET AND REPORTING CO DE’1O. ;$~nK TERM 11. CONTRACTOR NAME (See insrwcrims]: Nome of Lwilfty. City, State, Zip Code 16. lsthls task 17. Ooes this task include 18. TASK DESCRIPTION (Approach, rel~tion to wrk peckage. in 200 words or less) An in–depth study of all information pertaining to BRAVO test fallout on Rongelap and Utirik will be made. In addition, using advanced analytical and com– puter Techniques, a comprehensive fallout model will be developed. Using this model in conjunction with dietary and life st-yle pa’cterns prevalent at time of ex– posure, a reassessed dose estimate–-internal and external--will be made for the populations of Rongelap and Ut<rik. These dose estimates will. be evaluated in terms of the thyroid nodule incidence in these populations, and the results ob– tained will provide information towards correlating doses and radiation effects.

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TASK REQUIREMENTS FOR OPERATING/EQUIPMENT COSTS AND OBLIGATIONS Associated Universities, Inc. WORK PACKAGE NUMBER TASK NO. REV. NO. DATE PREPARED c TOT AL DIR ECT ......... 0.9 G.1 0.1 b. EQUIP MENT OBLIGATIONS. 0 0 0 0 Consunt BY dollars d. TOTAL EOUIPMENT OBLIGATIONS PROPOSED SCHEDULE AUTHORIZED SCHEDUL=

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TITLE BUDGET AND REPORTING CODE DATE PREPARED Dose Reassessment for Rongelap H.i-02-ol-ol 03/31/80 CONTRACTOR NAME CODE WP NUMBER TASK NO REV. NO - Assocloted Untversltles, Inc BNL o It is anticipated that work for this proposal will use existing Laboratory facilities and site utility services. in this study has been used in other reports. To look for correlations between the incidence of thyroid nodules in the inhabitants of Rongelap and Utirik Islands (Marshall Islands) and the reassessed This study will fuse together all available information on fallout from t}le BRAVO test and using advanced analytical techniques (now available) derive real– istic dose estimates to the inhabitants of Rongelap and Utirik. The results should provide information towards assessment of the risk coefficients for radiation– induced thyroid disease. Incidence of thyroid nodules, benign and malignant, in the exposed populations of Utirik and Rongelap has indicated critical differences in correspondence between nodule incidence and thyroid dose for the populations. The estimat– ed external dose received from the time fallout began to the time of evacuation shows that the ?,ongelap population received an external dose (175 rads) which was about 13 times that for the Uti.rik population (14 rads), ancl the thyroid dose was about 10 tines lal-ger, whereas the incidence of thyroid nodules in the two popula- .tions were not significantly different. A preliminary study has indicated that the critical area of investigation is the period starting from [he beginning of fallout to the completion of evacua– tion for both the islands. In addition, the fact that the Utirik population re– turned within 120 days following evacuation, whereas the Rongelap population re– turned only after three years, requires that we look closely at the Utirik popula- ~iOIl in terms of a longer exposure period, both internal and external, Further studies would, therefore, have to concentrate on the re-examination of all available data in reports issued by various agencies during that period, consultations with scientific personnel invoLved at that time, identifying the areas of uncertainty, and using appropriate computer programs to analyze the data. The encl result will enable US to look for correlations between the incidence of thyroid nodules and the reassessed dose estimates.

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TITLE BUDGET AND REPORTING CODE DATE PREPARED Dose Reassessment for Rongelap Associated Universities, Inc. CODE WP NUMBER TASK NO. REV. NO. The study will comprise: a. Literature search for all available data concerning the BRAVO test, such as, meteorological conditions and radiation measurements. Discussions with scientific and technical ‘personnel involved in the BRAVO test. Use of historic samples and teeth samples to determine 1291, 90Sr, and ~3~; 240Pu concentrations to derive concentrations of other radionucldies. In addition, excised thyroid glands from exposed Marshallese will be analyzed for 1291 and ‘9Tc and data so generated will be used to estimate the concentrations of short lived iodine isotopes. c. Diet and life style studies to provide information for dose assessment. d. Computer simulation of the BRAVO test fallout to determine the transport and deposition of radionuclides. Fiscal control will be exercised in the form of monthly comparisons, over the task term, of actual costs incurred against corresponding line items of the budget. Technical results shall be monitored through a periodic review, by the Contractor Task )Ianager, of accomplishments by measuring actual performance as compared to expected progress. All. work shall be conducted in conformance with generally accepted standards for R&D and other investigative or analytic procedures, as observ– ed by universities and large independent research facilities including Brookhaven A preliminary literature search and consultations with Dr. C.A. Sondhaus, University of California, have been completed. This has resulted in defining areas of uncertainty in information available and establishing the procedural steps that should be carried out to reassess the dose estimates. ,\ll available data on ex– ternal radiation measurements, radionuclide concentrations in soil, water, veSeta– tion, animal and food items have been collated. Historic samples collected from Rongelap and Utirik have been submitted for 1291 analysis. Pertinent meteoro– logical data pertaining to the BRAVO test has been researched and the information supplied to Lawrence Livermore Laboratory so ~ha~ they can go ahead with the com– puter simulation of fallout transportation and deposition. The 1291 determinations of the soil samples have been completed for those historic samples that were available. Some of these samples will also be analyzed for 99Tc. In addition, we are exploring the possibility of analyzing “Bikini-

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TITLE BUDGET AND REPORTING CODE DATE PREPARED Dose Reassessment for Rongelap HA-02-01-01 03/31/80 CONTRACTOR NAME CODE WP NUMBER TASK NO. REV. NO, Ass. ocloted Universilles, Inc. BNL o -20f. Technical Progress cont. ash” the fallout material that settled on the Japanese fishing vessel. These samples should provide the most accurate characterization of the fallout. Preliminary computer simulations of fallout transportation and deposition have been completed. Data analysis of the recent diet and life style study has been completed. Discussion with scientists and technical people who were involved with the BRAVO test is being continued. Analysis of the Marshallese teeth samples for Pu isotopes is in progress. .~ final report on the diet and life style for the Marshallese will be com– pleted. The computer simulation of fallout will also be com leted. from the exposed Marshallese will be analyzed for ‘9Tc and 1 ‘1. Analysis of the “Bikini-ash” will be done as soon as we get an aliquot of the sample. It is also expected that data on the exposed Japanese fishermen will be made available at that time. Preliminary analysis of the data generated so far will be made using existing models. The results will be extrapolated to present times so as to test the validity of the models used. Expected Progress in BY-1 (1981). ( Final dose estimates to the exposed inhabitants of Utirik and Rongelap should be completed. The methodology developed will be extended to Likiap and other islands which were on the “fringe” of the fallout pattern. The techniques and expertise developed in the course of this study could be used to reassess doses to population in other areas subjected to exposure from fal].out or even those resulting from occupational situations in the past. ~oh. Relationship to Other Projects. a. This study will help establish dose estimates from the time of the inci– dent to the present, and will complement the aerial survey for external radi,+tion neasurenents , over these islands, which has been completed. Together tl]ey should present a reliable picture of doses received by the populations and also enable dose estimates to be projected Into the future. b. This study w1ll be in close conjunction with the BNL Radiological Safety Program in the Marshall Islands (I{A--02-O1-O2) and with reiaked programs of the sity of Washington, Labora~ory of Radiation Ecology, and the Battelle Pacific Northwest Laboratory will be maintained in the area of sample analysis and data

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TITLE BUDGET AND REPORTING CODE DATE PREPARED Dose Reassessment for Rongelap HA-02-01-01 03131180 CONTRACTOR NAME CODE WP NUMBER TASK NO. REV. NO Nork done under this task proposal has either no environmental impact or has impacts similar to those described in and covered by BNL’s Environmental Impact