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Bikini Atoll

Bikini atoll

The primary objective of the Manhattan Project during World War II was the creation of a nuclear fission or atomic bomb. Even before that goal was accomplished in 1945, however, some nuclear scientists were thinking about the next step in the development of nuclear weapons , a fusion or hydrogen bomb.

Progress on a fusion bomb was slow. Questions were raised about the technical possibility of making such a bomb, as well as the moral issues raised by the use of such a destructive weapon. But the detonation of an atomic bomb by the Soviet Union in 1949 placed the fusion bomb in a new perspective. Concerned that the United States was falling behind in its arms race with the Soviet Union, President Harry S. Truman authorized a full-scale program for the development of a fusion weapon.

The first test of a fusion device occurred on October 31, 1952, at Eniwetok Atoll in the Marshall Islands in the Pacific Ocean. This was followed by a series of six more tests, code-named "Operation Castle," at Bikini Atoll in 1954. Two years later, on May 20, 1956, the first nuclear fusion bomb was dropped from an airplane over Bikini Atoll.

Bikini Atoll had been selected in late 1945 as the site for a number of tests of fission weapons, to experiment with different designs for the bomb and to test its effects on ships and the natural environment .

At that time, 161 people belonging to 11 families lived on Bikini. Since the Bikinians have no written history, little is known about their background. According to their oral tradition, the original home of their ancestors is nearby Wotje Atoll. Until the early 1900s, they had relatively little contact with strangers and were regarded with some disdain even by other Marshall Islanders. After the arrival of missionaries early in the twentieth century, the Bikinians became devout Christians. People lived on coconuts, breadfruits, arrowroot, fish, turtle eggs, and birds, all available in abundance on the atoll. The Bikinians were expert sailors and fishermen. Land ownership was important in the culture, and anyone who had no land was regarded as lacking in dignity.

On January 10, 1946, President Truman signed an order authorizing the transfer of everyone living on Bikini Atoll to the nearly uninhabited Bongerik Atoll. The United States Government asked the Bikinians to give up their native land to allow experiments that would bring benefit to all humankind. Such an action, the Americans argued, would earn for the Bikinians special glory in heaven. The islanders agreed to the request and, along with their homes, church, and community hall, were transported by the United States Navy to Rongerik.

In June and July of 1946, two tests of atomic bombs were conducted at Bikini as part of "Operation Crossroads." More than 90 vessels, including captured German and Japanese ships along with surplus cruisers, destroyers, submarines, and amphibious craft from the United States Navy, were assembled. Following these tests, however, the Navy concluded that Bikini was too small and moved future experiments to Eniwetok Atoll.

The testing of a nuclear fusion device in Operation Castle marked the return of bomb testing to Bikini. The most memorable test of that series took place in 1954 and was code-named "Bravo." Experts expected a yield of six megatons from the hydrogen bomb used in the test, but measured instead a yield of 15 megatons, 250% greater. Bravo turned out to be the largest single explosion in all of human history, producing an explosive force greater than all of the bombs used in all the previous wars in history.

Fallout from Bravo was consequently much larger than had been anticipated. In addition, because of a shift in wind patterns, the fallout spread across an area of about 50,000 mi2 (11.5 km2), including three inhabited islandsRongelap, Itrik, and Rongerik. A number of people living on these islands developed radiation burns and many were evacuated from their homes temporarily. Farther to the east, a Japanese fishing boat which had accidentally sailed into the restricted zone was showered with fallout. By the time the boat returned to Japan, 23 crew members had developed radiation sickness . One eventually died of infectious hepatitis, probably because of the numerous blood transfusions he received.

The value of Bikini as a test site ended in 1963 when the United States and the Soviet Union signed the Limited Test Ban Treaty which outlawed nuclear weapons testing in the atmosphere , the oceans, and outer space. Five years later, the United States government decided that it was safe for the Bikinians to return home. By 1971, some had once again take up residence on their home island. Their return was short-lived. In 1978, tests showed that returnees had ingested quantities of radioactive materials much higher than the levels considered to be safe. The Bikinians were relocated once again, this time to the isolated and desolate island of Kili, 500 mi (804 km) from Bikini.

The primary culprit on Bikini was the radioactive isotope cesium-137. It had become so widely distributed in the soil , the water, and the crops on the island that no one living there could escape from it. With a half life of 30 years, the isotope is likely to make the island uninhabitable for another century.

Two solutions for this problem have been suggested. The brute-force approach is to scrape off the upper 12 in (30 cm) of soil, transport it to some uninhabited island, and bury it under concrete. A similar burial site, the "Cactus Crater," already exists on Runit Island. It holds radioactive wastes removed from Eniwetok Atoll. The cost of clearing off Bikini's 560 acres (227 ha) and destroying all its vegetation (including 25,000 trees) has been estimated at more then $80 million. A second approach is more subtle and makes use of chemical principles. Since potassium replaces cesium in soil, scientists hope that adding potassium-rich fertilizers to Bikini's soil will leach out the dangerous cesium-137.

At the thirtieth anniversary of Bravo, the Bikinians had still not returned to their home island. Many of the original 116 evacuees had already died. A majority of the 1,300 Bikinians who then lived on Kili no longer wanted to return to their native land. If given the choice, most wanted to make Maui, Hawaii, their new home. But they did not have that choice. The United States continues to insist that they remain somewhere in the Marshall Islands. The only place there they can't go, at least within most of their lifetimes, is Bikini Atoll.

[David E. Newton ]



Davis, J. "Paradise Regained?" Mother Jones 18 (March/April 1993): 17.

Delgado, J. P. "Operation Crossroads." American History Illustrated 28 (May/June 1993): 5059.

Eliot, J. L., and B. Curtsinger. "In Bikini Lagoon Life Thrives in a Nuclear Graveyard." National Geographic 181 (June 1992): 7083.

Lenihan, D. J. "Bikini Beneath the Waves." American History Illustrated 28 (May/June 1993): 6067.

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