Marshall Islands Dose Assessment and Radioecology Program
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Test History

Brief History of Nuclear Testing in the Marshall Islands

Joint Task Force

Immediately after World War II, the United States created a Joint Task Force to develop a nuclear weapons testing program. Planners examined a number of possible locations in the Atlantic Ocean, the Caribbean, and the Central Pacific but decided that coral atolls in the northern Marshall Islands offered the best advantages of stable weather conditions, fewest inhabitants to relocate, and isolation with hundreds of miles of open-ocean to the west where trade winds were likely to disperse radioactive fallout. During the period between 1945 and 1958, a total of 67 nuclear tests were conducted on Bikini and Enewetak Atolls and adjacent regions within the Republic of the Marshall Islands. The most significant contaminating event was the Castle Bravo test conducted on March 1, 1954 (Figure 2). Bravo was an experimental thermonuclear device with an estimated explosive yield of 15 MT (USDOE, 2000) and led to widespread fallout contamination over inhabited islands of Rongelap and Utrōk Atolls, as well as other atolls to the east of Bikini. Today, the U.S. Department of Energy (U.S. DOE) through the Office of Health Studies continues to provide environmental monitoring, healthcare, and medical services on the affected atolls.

Key directives of the Marshall Islands Dose Assessment and Radioecology Program conducted at the Lawrence Livermore National Laboratory are (1) to provide technical support services and oversight in establishing radiological surveillance monitoring programs for resettled and resettling populations in the northern Marshall Islands; (2) to develop comprehensive assessments of current (and potential changing) radiological conditions on the islands; and (3) provide recommendations for remediation of contaminated sites and verify the effects of any actions taken.

Figure 2:

Map of the Republic of Marshall Islands showing the fallout pattern from the Bravo nuclear test conducted on March 1, 1954.

Last Modified: 28-JULY-2021 | LLNL-WEB-506535 | Contact Us
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