Nuclear testing at Bikini Atoll



The nuclear weapons testing at Bikini Atoll program was a series of 23 nuclear devices detonated by the United States between 1946 and 1958 at seven test sites. The test weapons were detonated on the reef itself, on the sea, in the air and underwater with a combined fission yield of 42.2 Mt. The testing began with the Operation Crossroads series in July 1946. The Baker test's radioactive contamination of all the target ships was the first case of immediate, concentrated radioactive fallout from a nuclear explosion. Chemist Glenn T. Seaborg, the longest-serving chairman of the Atomic Energy Commission, called Baker "the world's first nuclear disaster."

The United States was in a Cold War Nuclear arms race with the Soviet Union to build bigger and better bombs. The next series of tests over Bikini Atoll was code named Operation Castle. The first test of that series was Castle Bravo, a new design utilizing a dry fuel thermonuclear hydrogen bomb. It was detonated at dawn on March 1, 1954. The 15 megaton nuclear explosion far exceeded the expected yield of 4 to 8 megatons (6Mt predicted), and was about 1,000 times more powerful than each of the atomic bombs dropped on Hiroshima and Nagasaki during World War II. The scientists and military authorities were shocked by the size of the explosion and many of the instruments they had put in place to evaluate the effectiveness of the device were destroyed.

Bikini's native residents were promised they would be able to return home after the nuclear tests and agreed to leave the island. Most were moved to the Rongerik Atoll. Later nuclear tests in the 1950s rendered Bikini unfit for habitation, contaminating the soil and water, making subsistence farming and fishing too dangerous. The United States provided $150 million in compensation for damage caused by the nuclear testing program and their displacement from their home island.

Operation Crossroads


Operation Crossroads was a series of nuclear weapon tests conducted by the United States at Bikini Atoll in mid-1946. It was the first test of a nuclear weapon since the Trinity nuclear test in July 1945, and the first detonation of a nuclear device since the atomic bombing of Nagasaki on August 9, 1945. Its purpose was to investigate the effect of nuclear weapons on naval ships.

Crossroads consisted of two detonations, each with a yield of 23 ktonTNT: Able was detonated at an altitude of 520 ft on July 1, 1946; Baker was detonated 90 ft underwater on July 25, 1946. A third burst, Charlie, planned for 1947, was canceled primarily because of the United States Navy's inability to decontaminate the target ships after the Baker test. Charlie was rescheduled as Operation Wigwam, a deep water shot conducted in 1955 off the California coast. The Crossroads tests were the fourth and fifth nuclear explosions conducted by the United States (following the Trinity test and the bombings of Hiroshima and Nagasaki). They were the first of many nuclear tests held in the Marshall Islands and the first to be publicly announced beforehand and observed by an invited audience, including a large press corps.

Despite the government's promises that the inhabitants would be able to return home soon, the series of large thermonuclear tests rendered Bikini unfit for subsistence farming and fishing. Except for a skeleton crew of caretakers and occasional scientists, Bikini remains uninhabited as of 2014, though it is occasionally visited by sport divers. Although the government claimed that participants in the Operation Crossroads tests were well protected against radiation sickness, one study showed that the life expectancy of participants was reduced by an average of three months. The Baker test contaminated all of the target ships. It was the first case of immediate, concentrated local radioactive fallout from a nuclear explosion. Chemist Glenn Seaborg, the longest-serving chairman of the Atomic Energy Commission, called Baker "the world's first nuclear disaster."

To conduct the tests, the United States assembled a support fleet of more than 242 ships that provided quarters, experimental stations, and workshops for more than 42,000 personnel. The islands were primarily used as recreation and instrumentation sites. To support the nuclear bomb testing program, the personnel built bunkers, floating dry docks, 75 ft steel towers for cameras and recording instruments, and other facilities on the island.

Cross Spikes Club


The Cross Spikes Club was an improvised bar and hangout created by servicemen on Bikini Island between June and September 1946 during the preparation for Operation Crossroads. The "club" was little more than a small open-air building that served alcohol to servicemen and provided outdoor entertainment, including a ping pong table. The Cross Spikes Club has been described as "the only bright spot" in the Operation Crossroads experience. The club, like all military facilities on the island, was abandoned or dismantled following the completion of Operation Crossroads.

Ship graveyard
The Bikini Atoll lagoon was designated a ship graveyard by the United States Navy. The United States brought in 95 ships including carriers, battleships, cruisers, destroyers, submarines, attack transports, landing ships, and auxiliary vessels from across the world. The Navy positioned them in the lagoon to help assess the damage to vessels, equipment, and material from a nuclear explosion. Military equipment including tanks and other armor was positioned on some of the ships to see how well they survived the nuclear blast. Amphibious craft were berthed on Bikini Island for similar purposes. The proxy fleet would have made the sixth largest naval fleet in the world. The target ships included the U.S. carrier USS Saratoga (CV-3) and Admiral Yamamoto's 708 ft flagship, JAPANESE BATTLESHIP Nagato. All carried varying amounts of fuel and some carried live ordnance. Airplanes were positioned on the USS Saratoga (CV-3), their wings loaded with ordnance. Live animals including goats were positioned on the ships and shore to test for the impact on living creatures.

Weapons tests
Two fission bombs, both with a yield of 21 kilotons comparable to the bombs used on Japan, were tested first. A third test was planned, a deep underwater detonation, but was canceled. Able was dropped over Bikini on July 1, 1946, and exploded at an altitude of 520 ft but had drifted about 1500 to 2000 ft off target. It sank only five of the ships in the lagoon. The second, Baker, was detonated underwater at a depth of 90 ft on July 25, sinking eight ships. The second, underwater blast created a large condensation cloud and contaminated the ships with more radioactive water than was expected. Many of the surviving ships were too contaminated to be used again for testing and were sunk. The air-borne nuclear detonation raised the surface seawater temperature by 55000 °C, created blast waves with speeds of up to 8 m/s, and shock and surface waves up to 30 m high. Blast columns reached the floor of the lagoon which is approximately 70 m deep. The Bikini Island King visited Bikini Atoll in July after the second atomic bomb test code-named Baker and found it apparently in good condition.

Castle Bravo test
The United States was in a Cold War Nuclear arms race with the Soviet Union to build bigger and better bombs. The next series of tests over Bikini Atoll was code named Operation Castle. The first test of that series was Castle Bravo, a new design utilizing a dry fuel thermonuclear hydrogen bomb. It was detonated at dawn on March 1, 1954.

The 15 megaton nuclear explosion far exceeded the expected yield of 4 to 8 megatons (6Mt predicted), and was about 1,000 times more powerful than each of the atomic bombs dropped on Hiroshima and Nagasaki during World War II. The nuclear weapon was the most powerful device ever detonated by the United States (and just under one-third the energy of the Tsar Bomba, the largest ever tested). The scientists and military authorities were shocked by the size of the explosion and many of the instruments they had put in place to evaluate the effectiveness of the device were destroyed.

Castle Bravo contamination
The unexpectedly large yield, combined with other factors, led to the most significant accidental radiological contamination caused by the United States. A few minutes after the detonation, Fallout began to fall on Eneu/Enyu Island on Bikini atoll where the U.S firing crew that triggered the device were stationed, this was detected by their geiger counter, and as they were aware of the hazard, they were forced to shelter in place indoors for a number of hours before it was safe enough for an airlift rescue operation to be carried out. After arriving at Eneu, the fallout, being carried by the wind, then began to settle on the inhabited islands of the Rongelap and Utrik Atolls, arriving a few hours after the detonation, the fallout continued to spread around the world being diluted as it went. The inhabited Rongelap and Rongerik atolls were evacuated by US servicemen 48 hours after the detonation, and those on the more distant Utrik atoll, 72 hours post detonation. Many of the inhabitants soon began to show signs of radiation sickness. They were returned to the islands three years later but were removed again when their island was found to be unsafe.

The fallout spread traces of radioactive material as far as Australia, India and Japan, and even the United States and parts of Europe. Though organized as a secret test, Castle Bravo quickly became an international incident, prompting calls for a ban on the atmospheric testing of thermonuclear devices.

Local populations affected
The Rongelap Atoll was coated with up to 2 cm of snow-like irradiated calcium debris and ash over the entire island. Virtually all the inhabitants experienced severe radiation sickness, including itchiness, sore skin, vomiting, diarrhea, and fatigue. Their symptoms also included burning eyes and swelling of the neck, arms, and legs. The inhabitants were forced to abandon the islands, leaving all their belongings, three days after the test. They were relocated to Kwajalein for medical treatment.

Six days after the Castle Bravo test, the U.S government set up a secret project to study the medical effects of the weapon on the residents of the Marshall Islands.

The United States was subsequently accused of using the inhabitants as medical research subjects, without obtaining their consent, to study the effects of nuclear exposure. Until that time, the United States Atomic Energy Commission had given little thought to the potential impact of widespread fallout contamination and health and ecological impacts beyond the formally designated boundary of the test site.

Japanese fishermen contaminated
Ninety minutes after the detonation, 23 crew members of the Japanese fishing boat the Daigo Fukuryū Maru ("Lucky Dragon No. 5") also were contaminated by the snow-like irradiated debris and ash. They had no idea what the explosion they'd seen meant nor any inkling of the deadly debris raining down on them. But they all soon became ill with the affects of acute radiation poisoning. One fisherman died shortly after the ship reached shore. Edward Teller, father of the hydrogen bomb and architect of the Marshall Island tests, upon learning of the death of the fisherman, commented, “It’s unreasonable to make such a big deal over the death of a fisherman.” Eleven of the crewmen eventually died of radiation-related illnesses. The unexpected size of the explosion and the accidental fallout that contaminated a wide area sparked international criticism of atmospheric thermonuclear testing.

Later tests
The seventeen-shot Redwing series followed—eleven tests at Enewetak Atoll and six at Bikini. The island residents who had been promised they would be able to return home to Bikini was thwarted indefinitely by the U.S. decision to resume nuclear testing at Bikini in 1954. During 1954, 1956, and 1958, twenty-one more nuclear bombs were detonated at Bikini, yielding a total of 75 MtonTNT, equivalent to more than three thousand Baker bombs. Only one was an air burst, the 3.8 megaton Redwing Cherokee test. Air bursts distribute fallout in a large area, but surface bursts produce intense local fallout. The first after Crossroads was the dirtiest: the 15 megaton Bravo shot of Operation Castle on March 1, 1954, which was the largest-ever U.S. test. Fallout from Bravo caused radiation injury to Bikini islanders who were living on Rongelap Atoll.

These tests were followed by the 33-shot Hardtack tests which began in late April 1958. The last of tentests were detonated on Bikini Atoll on 22 July 1958.

Nuclear test list
The following nuclear device tests were conducted on or near Bikini Atoll.

Testing, radiation contamination and health problems
Following their evacuation from the island, an 11-year-old boy, born on Bikini in 1971, died from cancer that was linked to radiation exposure he received while living on Bikini. The records obtained by the Nuclear Claims Tribunal later revealed that Dr. Robert Conard, head of Brookhaven National Laboratory's medical team in the Marshall Islands, understated the risk of returning to the atoll. Dr. Konrad Kotrady was contracted by Brookhaven National Laboratory (BNL) to treat the Marshall Island residents. In 1977, he wrote a 14-page report to BNL that raised serious questions about the residents' return to Bikini and questioned the accuracy of Brookhaven's prior work on the islands. After they were promised their home was safe, and then being removed after this was found to be wrong, the Bikini Atoll islanders grew to distrust the official reports of the U.S. scientists.

The special International Atomic Energy Agency (IAEA) Bikini Advisory Group determined in 1997 that "It is safe to walk on all of the islands ... although the residual radioactivity on islands in Bikini Atoll is still higher than on other atolls in the Marshall Islands, it is not hazardous to health at the levels measured ... The main radiation risk would be from the food: eating locally grown produce, such as fruit, could add significant radioactivity to the body...Eating coconuts or breadfruit from Bikini Island occasionally would be no cause for concern. Eating many over a long period of time without having taken remedial measures, however, might result in radiation doses higher than internationally agreed safety levels." IAEA estimated that living in the atoll and consuming local food would result in an effective dose of about 15 mSv/year.

After the aborted resettlement in 1978, the leaders of the Bikini community have insisted since the early 1980s that the top 15 in of soil be excavated from the entire island. Scientists reply that while removing the soil would rid the island of cesium-137, it would also severely damage the environment, turning the atoll into a virtual wasteland of windswept sand. The Bikini Council has repeatedly contended that removing the topsoil is the only way to guarantee future generations safe living conditions.

In 1997, researchers found that the dose received from background radiation on the island was between 2.4 mSv/year&mdash;the same as natural background radiation&mdash;and 4.5 mSv/year, assuming that residents consumed a diet of imported foods. Because the local food supply is still irradiated, the group did not recommend resettling the island. A 1998 International Atomic Energy Agency report found that Bikini is still not safe for habitation because of dangerous levels of radiation.

A 2002 survey found that the coral inside the Bravo Crater has partially recovered. Zoe Richards of the ARC Centre of Excellence for Coral Reef Studies and James Cook University observed matrices of branching Porites coral up to 8 meters high.

Compensation and reparations
In 1975, when the islanders that had returned to Bikini Atoll learned that it wasn't safe, they sued the United States for the first time, demanding a radiological study of the northern islands. In 1975, the United States set up The Hawaiian Trust Fund for the People of Bikini, totaling $3 million. When the islanders were removed from the island in 1978, the U.S. added $3 million to the fund. The U.S. created a second trust fund, The Resettlement Trust Fund for the People of Bikini, containing $20 million in 1982. The U.S. added another $90 million to that fund to pay to clean up, reconstruct homes and facilities, and resettle the islanders on Bikini and Eneu islands.

In 1983, the U.S. and the Marshall islanders signed the Compact of Free Association, which gave the Marshall Islands independence. The Compact became effective in 1986 and was subsequently modified by the Amended Compact that became effective in 2004. It also established the Nuclear Claims Tribunal, which was given the task of adjudicating compensation for victims and families affected by the nuclear testing program. Section 177 of the compact provided for reparations to the Bikini islanders and other northern atolls for damages. It included $75 million to be paid over 15 years. On March 5, 2001, the Nuclear Claims Tribunal ruled against the United States for damages done to the islands and its people.

The payments began in 1987 with $2.4 million paid annually to entire Bikini population, while the remaining $2.6 million is paid into The Bikini Claims Trust Fund. This trust is intended to exist in perpetuity and to provide the islanders a 5% payment from the trust annually.

The United States provided $150 million in compensation for damage caused by the nuclear testing program and their displacement from their home island.

By 2001, of the original 167 residents who were relocated, 70 were still alive, and the entire population has grown to 2800. Most of the islanders and their descendents lived on Kili, in Majuro, and in the United States.