Note by the Secretary, Subject: Bikini Proposed Survey of Plutonium in Soils and Air (Encl; LTR to J a Erlewine re Same, DTD 4/13/70; Report on Bikini Atoll)

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BIKINI: PROPOSED SURVEY OF PLUTONIUM IN SOILS AND AIR Note by the Secretary The General Manager has requested that the attached memorandum of April 13, 1970 from the Director of Operational Safety, with the following attachment, be circulated for consideration by the Commission at the Information Meeting scheduled for Monday, Staff Report on Bikini Atoll. ........,..3 DISTRIBUTION NO. OF Secretary 7 Asst. GM for Admin. 1 Chairman Seaborg 4 Asst. GM for MA 2 Commissioner Ramey 1 Asst. GM for Operations 1 Commissioner Johnson 1 Asst. GM for R&D 1 Commissioner Larson Biology and Medicine General Manager 2 Congressional Relations : Deputy Gen. Mgr. 1 Controller 1 Asst. Gen. Mgr. 1 Inspection 1 Exec. Asst, to GM Special Asst. to GM 1' Operational Safety 1

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ATOMIC ENERGY COMMISSION THRU: John A. Erlewine, AGMO PROPOSED SURVEY OF PLUTONIUM IN SOILS AND IN AIR AT BIKINIATOLL Enclosed for your information is a staff paper on the need for additional radiological monitoring at Bikini Atoll. The higher levels of plutonium-239 and plutonium-240 reported for Bikini soil at two locations have been substantiated by additional analyses. However, analyses of samples from four other locations on Bikini show lower levels (from 1.3 to 39 pCi/g). Comparable field data for Rocky Flats and Palomares and comparison of measured concentrations in air with Concentration Guides indicates no cause for considering plutonium to be of health concern through ... the inhalation pathway at Bikini Atoll. Staff propose to augment present data by conducting another field trip to Bikini Atoll to The time for planning the survey and for coordinating plans with Trust Territory officials is minimal if the trip is to be conducted before the rainy season which begins about mid June. Draft reports containing results of the 1969 survey have been submitted to AEC for review and disposition. The staff proposes that the same NV contractors (SWRHL and University of Washington) participate in the 1970 survey and that results obtained from these further studies be incorporated in the draft reports prior to publication. The 1970 survey would provide a more comprehensive picture of radiological health aspects related to plutonium and confirm present determinations that these are negligible. ' The proposed 1970 survey could also indicate possible need for examination of plutonium situations at other atolls such as Rongelap and Staff Report on Bikini Atoll

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1. Background of Bikini Program Evacuation and Test Operations. early in 1946 it was determined that Bikini Atoll was a suitable site for nuclear weapons tests. The Bikini population, numbering 166, agreed to leave the atoll. After living some time on Rongerik Atoll the Bikini people were relocated to Kili live today. The Bikinians were promised and Kwajalein Island, Island where they still the return of their atoll when it was no longer needed as a testing site. : The Bikini field operations and test activities occurred periodically from 1946 through.1958. Luring this time, areas of the islands were cleared for camp sites and there was construction of housing, docks, towers and instrument bunkers. An aircraftI runway and parking ramp was built on nearby Eneu and another runway was constructed on a string of islands connected by man-made causeways along the southern rim of the reef. . *A total of 23 devices of both fission and thermonuclear types was detonated during 1946, 1954, 1956, and 1958. The islands of Bikini Atoll received fallout from these tests to varying degrees. The largest islands, Bikini and Eneu, located at the Eastern end of the atoll, were generally upwind of the detonation sites and

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thus receivedlessersmountsof falloutdebristhan some of the other islands. The relativelocationsof the islandsof BikiniAtoll and the test sites are shown in Figure1 with the numberof tests indicated in the circle. RadiologicalSurveys. An assessmentof the impactof test activities on the environmentat BikiniAtoll was begun shortlyafter the first two detonationswere conductedin 1.946. Surveyteams have revisited the atollbetweentestingperiodsand since testingwas concludedto obtainsamplesof marine life, land plantsand animals,soil,water and to spot-checkthe externalradiationlevelswithin the atoll. The most recent surveyswere conductedin 1964, 1967, and duringclean1964 Survey. The Divisionof Biologyand Medicine,throughits conAugust of 1964. Ten scientistsfrom the Universityof Washington, LaurenR. Donaldsonof the Universityof Washingtonspent two and one half weeks in EniwetokAtoll,ten days in BikiniAtoll, and two and one-halfdays at RongelapAtoll. The purposeof this surveywas to effectsof nucleartestsand relatedfalloutat these islands. This visit to BikiniAtoll produceda sizeablequantityof data on the

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radionuclide content of foods (marine and terrestrial) that would be . available to a returning population. Measurements of external radiation levels were less extensive. Islands were divided into several measurement areas and readings of gamma and beta-gamma were taken at.several locations in each erea. . Results of analyses of environmental samples collected in 1964 including analyses for plutonium-239 were published in ~~~-670503, Symposium on Radioecology, Proceedings of the Second National Symposium, Ann Arbor, Michigan, May 15-17, 1967, in a report by A. D. Welander entitled "Distribution of Radionuclides in the Environment of Eniwetok and Bikini Atolls, August 1964." The value reported for plutonium-239 in a single soil sample at the l/2" to 1" depth was 11 pCi/g. 1967 Survey. In December, 1966,the AEC, in responding to a request from the Secretary of the Department of Interior, agreed to make a determination on whether Bikini and its lagoon were safe for continued habitation and whether the Bikinians could have hazard-free use of the resources of the atoll and its adjacent water areas. Subsequently it was determined that the available survey data were not yet complete and that another team visit was needed to conduct a more,extensive survey of external radiation levels in Bikini Atoll. Also needed was a determination of the radionuclides that contributed to this radiation

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Planning for a major survey effort by the Division of Biology and Medicine began early in 1967. !l!he emphasis was on delineation of the external radiation fields,,particularly at locations of past and future habitation, and on obtaining more measurements.on all islands, including the smaller islands near test locations. Dr. Edward Held, University of Washington Marine Radiobiologist was appointed survey team leader. Team membership included personnel from AEC (BM, OS, HASL), AEC contractors, U. S. Trust Territory, and the U. S. Naval Radiological Defense Laboratory. Four native workers were added to the team in Kwajalein. The survey team spent 1.6 days at the atoll in April-May 1967 conducting an extensive survey of external radiation levels. Except for Adrikon, a very small island in the southwest corner of the atoll, all fourteen islands and,the two complexes of islands joined by man-made causeways were surveyed. Seven days were spent with studies on Bikini Island. In addition to monitoring external radiation, samples of food items, vegetation, and soil were collected and analyzed for radionuclide content. External radiation levels and the radionuclides contributing to those levels were-found to vary from island to island. On island6 more remote from testing activities such as Eneu and Bikini, the major contributor to the external gamma field is cesium-137.. The

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levels on Bikini were observed to be highest in the more heavily vegetated interior and lowest along the shore where there has been more weathering. On near test islands, the major contributor to the external gamma field was observed to be cobalt-60. Quantities of scrap metal containing cobalt-60 were found on these islands. Following the 1967 survey, the next significant step was taken by Dr. Philip F. Gustafson of the Division of Biology and Medicine,* who collected and summarized the data from all past surveys. Included in this material were reports from the Trust Territory DistrictAgriculturist and from the Trust Territory District Anthropologist. Dr. Gustafson prepared estimates of potential exposures, both internal . and external, for a returning population having living habits and diet that are expected to apply to the Bikinians. Also prepared were tentative recommendations with regard to the basic question of whether from a radiation exposure viewpoint the Bikinians should be allowed AEC Review. In April 1968, the Division of Biology and Medicine appointed the following Ad Hoc Committee to consider the question of-- John C. Bugher, Former Director EM, retired Robert A. Conard, Brookhaven National Laboratory Charles L. Dunham, Chairman, Division of Medical Sciences, NkC, NAY John H. Harley, Director HASL S. Allan Lough, Assistant Director for Radiological Physics, PM Shields Warren, Scientifid Director, Cancer Research Institute, New England Deaconess Hospital *Now at Argonne National Laboratory, Argonne, Illinois, USA

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The Committee members reviewed the survey data, Dri Gustafson's reports, and consulted with the team members of the 1967 survey. Based on this review, the Committee prepared a report stating that, on the basis of information provided, the exposures to radiation that would result from the repatriation of Bikini people do not offer.a significant threat to their health and safety. Key recommendations for actions to further reduce exposures included restriction of rehabilitation for the. present to the Bikini-Eneu complex, removal of radioactive scrap, reduction of land crab population, resurveys of the atoll. and village construction a dietary supplement of calcium, and periodic There were other recommendations for agricultural activities expected to reduce the radionuclide content of pandanus and reduce external radiation levels in village and dwelling sites. These reports and analyses formed the basis for discussions between various governmental groups, including AEC, the Department of Interior and DOD on rehabilitation and resettlement of 12, 1968, the President announced the decision that the to be returned to their atoll. At the same time AEC release providing background information relative to the decision and including the Ad Hoc Committee's report. The ABC and Department of Defense (DOD) were requested to work with the Department of Interior in planning and carrying out a comprehensive program for returning the Bikinians to their home islands; -To begin

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the planning, High Commissioner W. R. Norwood of the Trust Territory of the Pacific Islands led a party of Trust Territory officials, nine Bikini natives, AEC and DOD representatives, and members of the press, back to Bikini in late August, 1968. 1969 Operations and Survey. Cleanup operations commenced at Bikini in February 1969. DOD directed the cleanup phase of the rehabilitation project and this phase was completed in October 1969. DOD and AEC shared the cost of cleanup operations with each agency providing $300,000. AEC provided monitoring support during 1969 cleanup operations including guidance for disposal of scrap material. The vegetation removal operations carried out to provide space for replanting coconut groves also provided access to all parts of Bikini and Eneu Islands so that external radiation levels could be mapped and 1967, heavy vegetation placed a limitation on how much area During cleanup operations a significant number of additional'samples of foods, vegetation, soil and sediment, and well water were collected. Separate draft reports containing the external radiation measurements and results of analyses of radionuclide content of environmental samples (SWRBL) and fran the University of Washington. The SWRHL report contains results of analysis for plutonium-238 and plutonium-239 in soil at two locations on Eneman and the University of Washington report contains

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such results for one location on Eneman and two locations on Bikini. Except for plutonium levels in soil, the measurements of environmental radioactivity in these reports confirmed the results of the 1967 survey. The Department of Interior is presently conducting the agricultural recovery phase of the project and it was recently reported that housing construction is to begin about May of 1970. At present there are approximately 20 native workers and a Trust Territory representative at Bikini Atoll engaged in the agricultural program. 2. Levels of Alpha fritters in Soil and Air Bikini Atoll. As reported in Information Paper ABC 60&/124 dated March 23, 1970, the levels of plutonium-239 (and plutonium-240) in two soil ssmples for Bikini Island appear to be about a factor of 10 higher than the level reported for a sample collected in 1964. More recent analyses performed by the Southwestern Radiological Health Laboratory (SWRRL) and the University of Washington have confirmed levels for these two samples analyzed in 1969; samples from other locations on Bikini have proven to be somewhat lower. The values for Bikini Island range from 1.3 to 190 pCi/g, and for Eneu Island, from 0.5 to < 3 pCi/g of soil, as shown in Tables 1 and 2. Previous analyses for Eneman Island, a nearby test island not currently planned showed plutonium-239 levels ranging from 83 to 410

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Rocky Flats. In order to show possible relationships between soil levels and airborne levels of plutonium-239, data for Rocky Flats and Palomares have been examined. Levels of plutonium-239 in surface soil at 1 to more than 5 miles from the Rocky Flats plant range from 0.05 to 3 pCi/g, with an average of 0.5 pCi/g, as shown in Tables 1 and 3. However, the air monitoring network around Rocky Flats showed aversge gross alpha activity in airborne particulates at various stations ranging from 0.009 to 0.02 pCi/m3 for the last half of CY 1969, as given in Tables 1 and 6. Assuming the gross alpha activitiy to be of the Concentration Guide value for individuals in the general public, or 6$, for a suitable sample of the public. Air samples specifically analyzed for plutonium include a single sample taken by Dow in December, 1969, at the east security fence with a level of 0.002 pCi/m3, and six samples taken by the State of Colorado following the RF fire and processed by SWRHL. These latter samples averaged 0.005 pCi/m', with a range of 0.0001 to 0.02 pCi/m3. Palomsres. Levels of alpha emitters in soil at Palomares following the cleanup operations of / been reported both by levels of gross alpha surface stripping (area 2-l), plowing, etc., have Spanish authorities and by LASL. Background soil activity in regions of Spain not affected by the

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pendent on the type of soil, as shown in Table 4. Residual gross alpha activity in surface soil samples taken at Palomsres by Spanish authorities in September 1966, approximately 7 months after the incident, ranged from 5.1 to 214 pCi/g. Additional surface samples taken in the same areas and analyzed by LASL for plutonium activitiy had levels ranging from 0.05 to 2,130 pCi/g; areas 2-2 and 3-l had average plutonium levels of 134 and 156 pCi/g, respectively. These data are presented in Tables 1 and 5. It should be noted that the range of plutonium in surface soil in control areas at Palomares was 0.09-3.6 pCi/g. These areas were selected to be free of plutonium from the incident. This range is compsrable to that found at Rocky Air samplers to measure gross alpha activity in airborne particulates were set up in the three sreas of initial highest deposition, viz. 2-1, 2-2, and 3-2. For these sreas, the maximum gross alpha activity for the period 6/66-5/67 ranged from 0.05 to 0.14 pCi/m3, with an average of about 0.003 pCi/m3. These Palomares levels may be compared with background measurements made at Madrid during the same period: a maximum and average gross alpha activity level of 0.16 and 0.004 pCi/m3 in air, respectively. Again, assuming the I1 and for Madrid of the sample to be plutonium, the averages for Palomares would be on the …