Summary Sheet, Subject: Radiological Criteria for Enewetak Atoll (Policy Session Item)

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RADIOLOGICAL CRITERIA FOR ENEWETAK To obtain Commission approval of proposed radiological criteria for cleanup and rehabilitation of Enewetak. This paper covers a major policy issue re - c~uiring Commis sion approval. The paramount issue is whether and under what conditions the Enewetakese can be returned safely to their Atoll which is contaminated with debris and fallout from some 43 weapons test The staff recommends radiation criteria and plutonium soil contamination limits that pro tide a conservative margin of safety fcr people living there. Meetiaq these crit. +ria wiil require t’hat \illage sites be confined to the southern food (except COCOI: ILCS}be limited to tune southern tinued until the piltoriium contam.i~laticj~l is r~- Those Enewetakese whose homes were on t:e northern islands will be disappointed with tile restrictions on village sites in the north. J~WET was a major village site. :.

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The Defense Nuclear Agency (DNA), has taken exception to the proposed criteria, although by letter dated June 7, 1974, to the Chairman, ~he Directo; of DNA states that he “will not contest the standards recommended by the Commission. “ DNA believes that radiation standards applicable to the general public are not appropriate for the small Enewetak population and that such use could establish an undesirable precedent for other situations of environmental contamination from nuclear explosives. In-their view, application of standards for the general public does not allow adequate consideration of the desires of the people, especially as to establishment of a village on JANET. The DNA also recommended a risk-benefit analysis that they believe would justify the selection of higher radiation dose levels for th= cleanup criteria. Standards for radiation workers, or comparisons with situations where people live areas of India are cited as precedence for use of The Environmental Protection Agency (EPA) has commented favorably stating that they accept the proposed criteria on an interim use basis. The Department of the Interior (DOI) has deferred to AEC judgement. included in Appendix 1. Decision Criteria: Neither national nor international boclies h:,’. : cleanup that would apply specifi L-zl.l>~tc~ ~“~,c are developed on an ad hoc basis with cc)!-i~i(”~”--.i~r given to such pertinent factors as: exposure I.:l-:l.s. food chains, pathways to man, land use, cost, feasibility of cleanup, impact of cleanup, He. The staff has applied the principle that cleanup 01 contaminated property for use by t’ne general public must (1 ) keep predicted radiation C?OSC levels within a conservative interpretation and

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application of Federal guidance on radiation protection, and (2) meet the “as low as practicable” criterion considering factors of practicality and effectiveness. These principles were followed in the Bikini Atoll cleanup, the most appropriate precedent for Enewetak. The Enewetak cleanup and , rehabilitation recommendations, including the restrictions, are similar to those for Bikini. About the same order of conserva~ism was used in applying the standards. While there are no national or international criteria for plutonium cleanup, the staff recommendations are consistent with a recent independent study performed by IXSL entitled in Soils, “ LA-5483-MS, dated January 1974. EPA plans to develop cleanup guides for pluto contaminated land but these will not be availab for some time. Plutonium contamination on islands of Enewetak is conEined principally t well defined and relatively small areas. The exception is the contamination on YV’OIWQE; about half of the 94 acres of this island is highly contaminated. There is a wide range of particle sizes, and the distribution in the soil is not uniform. The recommended crite for cleanup of plutonium in the soil are Jnte:. for use throughout the islands of the .\toli. are also given. Decontamination of ‘{ VOR7NE seen as an iterative process to be Co:ld:uct.:d a team of experts. There remains ccc oiificu problem of disposal of the contamiriaceci soii which is a responsibility of DATA. iiowe~er, the time cleanup is started, a method for -~i may be available. H not, then the plutonium throughout the Atoll should be retained o~VON and the quarantine of that island continued u contamination is removed. Further study is on possible removal of the plutonium contami

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from soil to reduce the bulk of material requiring disposal. AEC should be prepared to take the lead in any such studies that are (1) Apply radiation criteria with the objective of maintaining exposure and radioactivity levels in the natural background range hibiting occupancy of the Atoll. ) (2) Apply maximum levels allowable for individuals within the general population as contained in current Federal standards such as 500 mRem/yr, and 5 Rem in 30 years whole body doses and inhalation and dietary intake of radio nuclides equivalent to those (3) A middle course based on maintaining exposures “as low as practicable, “ and limited to a conservative fraction of the Federal standards for individuals within the general population in order to account for uncertainties in dose estimates. Weapons tests were conducted at Enewetak Atoll from 1948 to 1958. The remaining contamination from 43 explosions includes fallout, fission debris, neutron activation products, plutoriit~~m debris from safety tests and buried waste. Test locations are shown in the attached map with namss of tests enclosed in boxes. Atoll would be placed under ‘Trust Territory control at the end of 1973. Resettlement of the Enewetakese people would depend upon the resulis of a survey of the Atoll using the same pattern cleanup, rehabilitation and resettlement. The responsibilities were divided among Federal

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agencies at an interagency meeting on September 1972, as follows: AEC-radiological survey and cleanup and rehabilitation criteria; Defense and resettlement. EPA optecl not to become involved formally, but agreed to advise and During September 1972 to March 1974, AEC ‘ conducted an extensive radiological survey. A Task Group was established to evaluate - the survey results and to prepare recommendations for cleanup and rehabilitation. The Task Group report was coordinated with DNA, DOI, SECY 74-542, Outline of a Staff Paper on Enewetak Atoll, was discussed with. the Commis sion at Session 74-74 on April 23, 1974. ‘The Commission generally accepted the propose staff rationale which would allow the people to occupy part of the Atoll with certain practical restrictions on living sites, food sources, etc. This is consistent with the staff position that exposures should be “as low as practicable” and based on conservative interpretation of Federal Radiation Council (FRC) guidelines. The Task Group report is a~a.ilable in the Secretariat and is summarized in Appendix ?. Key conclusions and recomrnendacions are as (1) FRC guides Ior whole body, bone, a~cl doses. Owing to uncertainties in dose estimates, the vaiues used to evaluate cleanup alternatives were the FRC guides reduced by 50 percent for annual dose%– to individuals and by .20 percent for the 30-year gonadal doses. Thus:

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Whole body and bone marrow - 0.25 Rem/yr Plutonium soil cleanup should be handled on a case-by-case basis considering all radiological condition s.’ Cleanup of contaminated soil should be implemented by a team of experts in the field using the following general guidance applicable to this specific operation. Decontamination of YVONNE is seen as an iterative process that amounts to a search for the higher plutonium levers in soil with removal and storage according to the guidance provided. Lf a method of plutonium disposal is not available during the cleanup phase, the quarantine of the island should Villages should be located on southern islands, ALVIN throllgh KEITH. Visits may be made to all islands except settlemcn~ rlow. Resettlement may occur w’nen test plantings of subsistence and commercial crops show radio activity~evels There should be base -line surveys of bocly ‘b’m”dcns of selected raciionuclides for the F2neweta”k people prior to return and periodic

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(10) The above restrictions result in the following calculated radiation doses: Maximum whole body dose - 0.13 R Maximum bone marrow dose - 0.15 R (11) In contrast, unrestricted living on JAN would result in the following radiation Maximum whole body dose - 0.76 Maximum bone marrow dose - 1.1 R Staff recommendations were derived followin consideration of various options for reduction of radiation close below the criteria including modification of the diet, plowing and removal and replacement of layers of contaminated soil. Associated ecological damage and soi disposal problems are una~-oidable consequen of large scale decontamination actions. Th Task Group did not view partial soil removal an effective :. nd dependable method of reduci radiation do S(-S. Consideration of restriction is abs~ii~t:~iy necessary if radiation doses a dose criteria. The Task Group did cocsi< , estimates of risks associated with radiation criteria derived from FRC guidance. Becau of many -~nc ertainties as sociated with ~redic of effects 01 long-term iow level doses from

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external and internal emitters for a base population of a few hundred people, the Task Group had severe reservations about the validity of the estimates. The recommendations of the Task Group are considered to be practicable and feasible. The largest cost item for the recommended cleanup would be the support base; the second largest item would be removal and disposal of contaminated and uncontaminated sc rap and the cleanup, remo’val and disposal of plutonium contaminated soil. Since the recommendations do not contemp~ate extensive decontamination of residual radioactivity in soil of northern islands such as JANET, the cost should be less than any approach involving extensive soil removal, disposal, and replacement Following consideration and approval of the Task Group findings, the staff will inform DNA and DOI. A briefing will then be developed and rehearsed for presentation to the people of Enewetak and their advisors during a joint AEC-IINA-DOI trip to the Pacific. This presentation will be designed to be a vehicle for U. S. Qvernment consultation with the people on the AEC recommendations and the proposed DNA-DOI Draft Envirorimental Impact Statement (DEIS). Opening remarks at the briefing would be delivered by senior AEC, DN-A, and DOI officials. In more detailed discussions to follow, AEC recommcnciations and the DEIS inforiq; the Commission of results of these d;.~~li:;:” , , Recommendations: 1. That alternative ‘3 and the associated crit::ri~. 2. N-ote that the responsibility for disposal of contaminated material, including piutonium,—

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3. N“ote that action on reducing the quantity of plutonium contaminated material r equiring disposal has been deferred for further study. The AEC should be prepared to take the lead in conducting a study to see if such reduction is feasible 4. Note that the follow-on radiological surveys and monitoring of the Atoll and people will be conducted by AEC t~ insure exposure criteria are not exceeded and to determine when JANET and other northern islands become habitable. 5. That consultation with the Enewetak people as discussed be approved. This paper has been concurred-in by DMA, BER, and O-GC, and has been noted by PA. at the August 6, 1974

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Deputy General Manager Exec Asst to Gen Mgr Asst Gen Mgr for Admin Asst Gen Mgr for Biomed G Env Research G Safety Programs Biomed G Env Research NO. OF COPIES