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Rongelap Atoll

People & Events | Resettlement


The Rongelap Atoll is one of the 29 atolls and 5 islands that make up the Republic of the Marshall Islands. The land area of Rongelap Atoll consists of 61 islets with a combined area of approximately 3 square miles. The lagoon covers 388 square miles.

People and Events on Rongelap Atoll

On On March 1, 1954, the United States conducted a nuclear test on Bikini Atoll in the northern Marshall Islands code named Bravo that led to widespread fallout contamination over inhabited islands of Rongelap, Ailinginae, and Utrōk Atolls. Prior to Bravo, little consideration was given to the potential health and ecological impacts of fallout contamination beyond the immediate vicinity of the test sites. A total of 64 people living on Rongelap Atoll (including people residing on Ailinginae Atoll at the time of the blast) received significant exposure to "fresh" radioactive fallout and had to be evacuated to Kwajalein Atoll for medical treatment. The Rongelap community spent the next 3 years living on Ejit Island (Majuro Atoll) before returning home to Rongelap in June 1957. However, growing concerns about possible long-term health effects associated with exposure to residual fallout contamination on the island prompted residents to relocate again to a new temporary home on Mejatto Island on Kwajalein Atoll in 1985. The people of Rongelap are still resident on Mejatto today although parts of the community have split off to live on Ebeye Island (Kwajalein Atoll) and Majuro Atoll.

The Rongelap community has always expressed a strong desire to return to their ancestral homeland. Through the Rongelap Resettlement Act, the United States Congress approved and continued a 1996 resettlement agreement between the United States and the Rongelap Atoll Local Government, and extended distribution authority for 10 years to advance resettlement. As a part of the 1996 resettlement agreement, a Phase I resettlement program was initiated in 1998. The United States Department of Energy, the Rongelap Atoll Local Government, and the Republic of the Marshall Islands have since signed a Memorandum of Understanding (MOU, 1999) outlining shared provisions in support of resettlement. Under this agreement, scientists from the Lawrence Livermore National Laboratory were tasked with developing individual radiation protection monitoring programs for resettlement workers and to verify the effects of the remedial actions.

Resettlement of Rongelap Atoll

Phase I resettlement of Rongelap Island is nearing completion. Rongelap Island now boasts a host of modern-day facilities including electrical power, a freshwater supply, a modern field station, paved runway, a number of bungalows for accomodating tourists and other visitors to the island, a whole-body counting facility and adjoining health physics laboratory, and a large concrete pier.

The remedial actions adopted under the Rongelap Resettlement Program are based on recommendations provided by scientists from the Lawrence Livermore National Laboratory. The remediation technique being employed is referred to as the combined option and involves replacing contaminated surface soil in the community-village area, where people spend most of their time, with a layer of clean crushed coral fill and adding potassium chloride fertilizer to the surrounding agricultural fields. Limited soil removal and addition of coral fill reduces external exposure to gamma/beta radiation as well as inhalation exposure to radioactive contamination in the air that people breathe. The addition of potassium fertilizer to the agricultural areas competitively blocks cesium-137 uptake into plants, especially into the fruits of the main subsistence crops such as coconuts. It is expected that addition of potassium fertilizer on Rongelap Island will reduce the ingestion dose from cesium-137 to about 30 % of the pretreatment level and, at the same time, help support plant growth and increase the productivity of plants (see related information under Bikini Atoll).

After living in exile for nearly 2 decades, the prospect that the people of Rongelap will soon return to their ancestral homeland is an important milestone in the history of the Marshall Islands Program. Moreover, the Rongelap resettlement program is among the first in which a local government has engaged the United States Department of Energy to develop shared provisions to monitor the return of the population.

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Satellite image of Rongelap Island showing (insert) the location of the community center where surface soil was removed and replaced with clean crushed coral fill (approximately 11.4 ha or 36.1 acres)

Reducing External Exposure

Contaminated soil around the proposed community center on Rongelap Island has been replaced with a layer of clean crushed coral to reduce external exposure to cesium-137 and other sources of penetrating radiation present in the underlying soil. The initial phase of this work was completed in March 2001. A detailed in-situ gamma monitoring survey of the entire community area was conducted in May 2001. Additional in-situ gamma surveys were carried out in 2006 to assess external gamma exposure rates around homesites. The results of these studies clearly show that the combination of limited soil removal and addition of crushed coral fill is very effective in reducing external gamma exposure rates. The clean surface layer of coral also has the added benefit of reducing potential exposures from inhalation and ingestion of plutonium and other long-lived radionuclides present in the soils. View full report: UCRL-ID-143680-Pt-1 (Hamilton et al., 2001).

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View of the village area on Rongelap Island after the addition of crushed coral fill and showing the restored church in the background.

Last Modified: 28-JULY-2021 | LLNL-WEB-400363 | Contact Us
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