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ASSESSING RADIOLOGICAL CONDITIONS AT AND THE PROSPECTS FOR RESETTLEMENT REVIEW AT BY PETER STEGNAR

ome testing during the 1954, Bikini Atoll was The history of the development of the reactivated as a test site until radiological assessments and Satomic bomb was done the US terminated nuclear- the movement of the local in countries that do not have weapon testing in the Marshall population is very important in the infrastructure and expertise in 1958. understanding the overall for evaluating any associated Prior to the first nuclear test concerns. In August 1968 — radiation risks. In such cases, in 1946, the 167 Bikinians following a number of outside expertise is needed to living on Bikini were radiological surveys that had obtain independent advice evacuated to , been carried out since 1958 to about the radiological situation about 200 kilometers to the assess the impact of the US caused by residual radioactive east, seemingly to reside there programme of nuclear-weapon material from nuclear testing. until an unspecified future date testing — it was announced The IAEA has been when the testing would be that Bikini Atoll was safe for requested by the governments completed. The Bikinians habitation and approved for of a number of its Member remained on Rongerik Atoll resettlement. The atoll was States to provide assistance in for a period of two years. In cleared of debris and fruit trees this context. Among the 1948, they were moved briefly were replanted. A further 15 former nuclear test sites which to and later in radiological survey of Bikini the IAEA has reviewed is the the same year to Kili, a small Atoll was carried out in 1970. Bikini Atoll of the Marshall . Eventually, 139 Bikinians Islands. Problems arose, however. resettled on the Atoll. They included the fact that However, the Bikinian people BACKGROUND Kili has no , no remained unconvinced of the AND HISTORY protective reef and no fishing safety of the Atoll, and in 1975 Bikini Atoll is located 850 kilo- grounds. The small is they initiated a lawsuit against meters northwest of on frequently subject to high the US Government to the northern fringe of the waves. The Bikinians saw the terminate the resettlement and is com- move to Kili as a temporary effort until a satisfactory and posed of more than 23 islands relocation and were reluctant comprehensive radiological and . Four islands (Bikini, to change from being survey had been carried out. Eneu, Nam and Enidrik) fishermen to being farmers. Additional radiological data account for over 70% of the By the time nuclear-weapon were collected for evaluation in land area. Bikini and Eneu are testing in the Marshall Islands 1975, 1976, and 1978. In the only islands of the atoll was terminated in July 1958, September 1978 it was decided that have had a permanent sixteen nuclear-weapon tests to relocate the 139 Bikinians population. had been conducted on Bikini who had returned to Bikini In 1946, Bikini Atoll was the Atoll over a 12-year period. All Atoll back to and to first site in the Marshall Islands of these tests were surface or Ejit Island at Majuro Atoll. used for nuclear-weapon atmospheric tests. They were testing by the . In conducted in or over the Atoll 1948, , a lagoon, thereby dispersing the Mr. Stegnar is a staff member of neighboring atoll, replaced explosion’s effects over all of the IAEA Division of Radiation Bikini Atoll as the test site. In the islands of the Atoll. and Waste Safety. IAEA BULLETIN, 40/4/1998 Doc-04.qxd 1/21/99 9:37 AM Page 16

After a second relocation, a Islands considered the survey team to Bikini Atoll to perform new radiological survey, findings but it did not accept a limited programme of envi- sponsored by the United them. ronmental measurements and States, was performed. This sampling. Measurements were survey consisted of using REQUEST FOR AN made of the absorbed dose rate detectors mounted in INTERNATIONAL in the air and of the concentra- helicopters to plot contours of REVIEW tion of the most radiologically external gamma dose rates. In 1994, the Government of significant radionuclides in Also, samples of vegetation, the Marshall Islands requested representative samples of soil marine foods, animals and soil the IAEA to conduct an inde- and foodstuffs. were collected and analyzed. pendent international review of The purpose of this survey Revised radiation dose the radiological conditions at was to validate the data that evaluations were published in Bikini Atoll, and to consider had been previously collected. 1980 and 1982. They and recommended strategies Measurements taken during indicated that — should the for the resettlement of the the survey were generally in Bikinians decide to resettle atoll. The IAEA responded to good agreement with their island — the terrestrial this request by convening an previously reported values. food chain would be the most Advisory Group , which met in significant exposure pathway. December 1995. The Group CONCLUSIONS This dose assessment was most was convened under the frame- Based on its review, the IAEA recently updated in 1995 on work of an IAEA technical co- Advisory Group determined the basis of a continuing operation project. that no further corroboration measurement programme at There were three main of the measurements and the Atoll. objectives of the international assessments of the radiological Following the US survey, the review: conditions at Bikini Atoll is Government of the Republic of ■ To assess the radiological necessary. The data that have 16 the Marshall Islands conditions on Bikini taking been collected are of sufficient commissioned a separate into account the information quality to allow an appropriate radiological assessment. By this submitted by the Republic’s evaluation to be performed. means, Bikini Atoll, as well as Government; The limited IAEA monitoring all other in the Republic, ■ To ascertain whether any of the area provided a good were to be monitored for corroboration of the available quality assurance verification of radioactive residues. A information on the the previously collected data. Scientific Advisory Panel of radiological conditions at the It was recommended that well-known and respected Atoll is needed; and Bikini Island should not be scientists provided oversight. ■ To determine whether any permanently resettled under Laboratory quality control remedial actions for the pur- the present radiological programmes were pose of radiation protection conditions. This implemented to ensure that the were required and, if so, the recommendation was based on surveys could provide accurate form, scale and duration of the assumption that persons measurements and such an intervention. resettling on the island would reproducible data. In general, The international review consume a diet of entirely the study confirmed the took into account all of the locally produced food. The findings of earlier available data from the radiological data support that measurement programmes. Marshall Islands’ survey, as well if a diet of this type were The findings of the survey as of a large number of other permitted, it could lead to an were published and a report on assessments made by scientists annual effective dose of about Bikini Atoll was released in from around the world. 15 mSv. This level was judged February 1995. to require intervention of some In August 1995, six months IAEA SURVEY OF type for radiation protection after the survey report was BIKINI ATOLL purposes. issued, the Nitejela In May 1997, the IAEA sent There are a number of IAEA BULLETIN, 40/4/1998 (Parliament) of the Marshall an environmental monitoring remedial actions that could be Doc-04.qxd 1/21/99 9:37 AM Page 17

If it is determined to remediate Bikini Island through the use of fertilizers, it was recommended that a simple monitoring programme of the foodstuffs and the population be continued. The purpose of this programme is to provide assurance to the local population that there is no significant uptake of radioactive material into their bodies. This project was an example of a study where the IAEA was asked to provide an assessment of an existing radiological situation arising from the presence of radioactive residues. It provided this service to a Member State that had legitimate concerns about these situations. By providing this service, the IAEA has helped provide guidance to national authorities on possible actions that can be taken for 17 the purpose of resettlement in areas where there are concerns about existing environmental conditions. In 1998, the IAEA issued a report — Radiological Conditions at Bikini Atoll: Prospects for Resettlement — that covers the international review in greater detail. (See this edition’s IAEA Books section for ordering information.) performed that could lead to potassium would replace this Additionally, in July 1997, the permanent rehabitation of the element, thereby reducing the official journal of the Health island. These include the overall exposure to the Physics Society, Health Physics, periodic application of population. The scraping and devoted a special edition to the potassium-based fertilizer removal of the topsoil would subject, including papers of where edible crops are grown cause serious environmental direct relevance to questions of or the removal of the topsoil harm to the island and have resettlement for the people of from the island. It is generally social consequences. Bikini Atoll. ❐ felt that the most reasonable approach would be to use Photos: As part of the IAEA’s international review of Bikini Atoll, expert potassium fertilizer. Since most teams collected and analyzed environmental samples at a number of sites. of the radioactivity in the Shown here is the preparation of for the measurement of plants is due to the uptake of radioactivity and soil profile sampling on Bikini Island. the radioactive cesium, the (Credit: G. Winkler/IAEA) IAEA BULLETIN, 40/4/1998