Pacific Proving Grounds
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The Pacific Proving Grounds was the name given by the
United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
government to a number of sites in the
Marshall Islands The Marshall Islands, officially the Republic of the Marshall Islands, is an island country west of the International Date Line and north of the equator in the Micronesia region of the Northwestern Pacific Ocean. The territory consists of 29 c ...
and a few other sites in the
Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five Borders of the oceans, oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is ...
at which it conducted
nuclear testing Nuclear weapons tests are experiments carried out to determine the performance of nuclear weapons and the effects of Nuclear explosion, their explosion. Nuclear testing is a sensitive political issue. Governments have often performed tests to si ...
between 1946 and 1962. The U.S. tested a nuclear weapon (codenamed Able) on
Bikini Atoll Bikini Atoll ( or ; Marshallese language, Marshallese: , , ), known as Eschscholtz Atoll between the 19th century and 1946, is a coral reef in the Marshall Islands consisting of 23 islands surrounding a central lagoon. The atoll is at the no ...
on June 30, 1946. This was followed by
Baker A baker is a tradesperson who baking, bakes and sometimes Sales, sells breads and other products made of flour by using an oven or other concentrated heat source. The place where a baker works is called a bakery. History Ancient histo ...
on July 24, 1946 (dates are
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, local dates were July 1 and 25, respectively). On July 18, 1947, the United States secured an agreement with the
United Nations The United Nations (UN) is the Earth, global intergovernmental organization established by the signing of the Charter of the United Nations, UN Charter on 26 June 1945 with the stated purpose of maintaining international peace and internationa ...
to govern the islands of Micronesia as the
Trust Territory of the Pacific Islands The Trust Territory of the Pacific Islands (TTPI) was a United Nations trust territory in Micronesia administered by the United States from 1947 to 1994. The Imperial Japanese South Seas Mandate had been seized by the U.S. during the Pacifi ...
, a strategic trusteeship territory. This is the only such trusteeship ever granted by the United Nations to the United States. The Trust Territory comprised about 2,000 islands spread over of the
North Pacific Ocean North is one of the four compass points or cardinal directions. It is the opposite of south and is perpendicular to east and west. ''North'' is a noun, adjective, or adverb indicating direction or geography. Etymology The word ''north'' ...
. Five days later, the
United States Atomic Energy Commission The United States Atomic Energy Commission (AEC) was an agency of the United States government established after World War II by the U.S. Congress to foster and control the peacetime development of atomic science and technology. President Harry ...
established the Pacific Proving Grounds. The United States conducted 105
atmospheric An atmosphere () is a layer of gases that envelop an astronomical object, held in place by the gravity of the object. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A stellar atmosphere ...
and underwater (i.e., not underground)
nuclear test Nuclear weapons tests are experiments carried out to determine the performance of nuclear weapons and the effects of their explosion. Nuclear testing is a sensitive political issue. Governments have often performed tests to signal strength. Bec ...
s in the Pacific, many with extremely high yields. While the Marshall Islands testing composed 14% of all U.S. tests, it composed nearly 80% of the total yields of those detonated by the U.S., with an estimated total yield of around 210 megatons, with the largest being the 15 Mt
Castle Bravo Castle Bravo was the first in a series of high-yield thermonuclear weapon design tests conducted by the United States at Bikini Atoll, Marshall Islands, as part of ''Operation Castle''. Detonated on 1 March 1954, the device remains the most powe ...
shot of 1954 which spread considerable
nuclear fallout Nuclear fallout is residual radioactive material that is created by the reactions producing a nuclear explosion. It is initially present in the mushroom cloud, radioactive cloud created by the explosion, and "falls out" of the cloud as it is ...
on many of the islands, including several that were inhabited and some that had not been evacuated. Many of the islands which were part of the Pacific Proving Grounds are still contaminated from the
nuclear fallout Nuclear fallout is residual radioactive material that is created by the reactions producing a nuclear explosion. It is initially present in the mushroom cloud, radioactive cloud created by the explosion, and "falls out" of the cloud as it is ...
, and many of those who were living on the islands at the time of testing have suffered from an increased incidence of various health problems. Through the Radiation Exposure Compensation Act of 1990, at least $759 million has been paid to Marshall Islanders as compensation for their exposure to U.S. nuclear testing. Following the Castle Bravo accident, the U.S. paid $15.3 million to
Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...
. Scientists have calculated that the residents of the
Marshall Islands The Marshall Islands, officially the Republic of the Marshall Islands, is an island country west of the International Date Line and north of the equator in the Micronesia region of the Northwestern Pacific Ocean. The territory consists of 29 c ...
during their lifetimes will be diagnosed with an added 1.6% (with 90% uncertainty range 0.4% to 3.4%) cancers attributable to fallout-related radiation exposures. The cancers are the consequence of exposure to
ionizing radiation Ionizing (ionising) radiation, including Radioactive decay, nuclear radiation, consists of subatomic particles or electromagnetic waves that have enough energy per individual photon or particle to ionization, ionize atoms or molecules by detaching ...
from weapons test fallout deposited during the testing period (1948–1958) and from residual radioactive sources during the subsequent 12 years (1959–1970).


Strategic Trust Territory

On July 18, 1947, the United States convinced the United Nations to designate the islands of Micronesia as the Strategic Trust Territory. This was the only trust ever granted by the U.N. The directive stated that the United States should "promote the economic advancement and self-sufficiency of the inhabitants, and to this end shall... protect the inhabitants against the loss of their lands and resources..." The
United States Navy The United States Navy (USN) is the naval warfare, maritime military branch, service branch of the United States Department of Defense. It is the world's most powerful navy with the largest Displacement (ship), displacement, at 4.5 millio ...
controlled the Trust from a headquarters in
Guam Guam ( ; ) is an island that is an Territories of the United States, organized, unincorporated territory of the United States in the Micronesia subregion of the western Pacific Ocean. Guam's capital is Hagåtña, Guam, Hagåtña, and the most ...
until 1951, when the
United States Department of the Interior The United States Department of the Interior (DOI) is an United States federal executive departments, executive department of the Federal government of the United States, U.S. federal government responsible for the management and conservation ...
took over control, administering the territory from a base in
Saipan Saipan () is the largest island and capital of the Northern Mariana Islands, an unincorporated Territories of the United States, territory of the United States in the western Pacific Ocean. According to 2020 estimates by the United States Cens ...
. Despite the promise to "protect the inhabitants", from July 1946 through July 1947, the residents of Bikini Atoll who had been relocated to Rongerik Atoll were starving for lack of food. A team of U.S. investigators concluded in late 1947 that the islanders must be moved immediately. Press from around the world harshly criticized the U.S. Navy for ignoring the people. Harold Ickes, a syndicated columnist, wrote "The natives are actually and literally starving to death." The islanders were later moved again to
Kili Island Kili Island or Kili Atoll (Marshallese language, Marshallese: , ) is a small, () island located in the Marshall Islands in the Pacific Ocean. As of 2021, 415 people lived on the island, many of whom were descended from islanders who originally li ...
, which is not surrounded by a reef. The island does not support the inhabitants' traditional way of life.


Radiation exposure

Because of the large amount of atmospheric testing, and especially the
Castle Bravo Castle Bravo was the first in a series of high-yield thermonuclear weapon design tests conducted by the United States at Bikini Atoll, Marshall Islands, as part of ''Operation Castle''. Detonated on 1 March 1954, the device remains the most powe ...
accident of 1954, many of the islands which were part of the Pacific Proving Grounds are still contaminated by
nuclear fallout Nuclear fallout is residual radioactive material that is created by the reactions producing a nuclear explosion. It is initially present in the mushroom cloud, radioactive cloud created by the explosion, and "falls out" of the cloud as it is ...
. Scientists calculated in 2010 that during the lifetimes of members of the
Marshall Islands The Marshall Islands, officially the Republic of the Marshall Islands, is an island country west of the International Date Line and north of the equator in the Micronesia region of the Northwestern Pacific Ocean. The territory consists of 29 c ...
population, potentially exposed to ionizing radiation from weapons test fallout deposited during the testing period (1948–1958) and from residual radioactive sources during the subsequent 12 years (1959–1970), perhaps 1.6% (with 90% uncertainty range 0.4% to 3.4%) of all cancers might be attributable to fallout-related radiation exposures. By sub-population, the projected proportion of cancers attributable to radiation from fallout from all nuclear tests conducted in the Marshall Islands is 55% (with a 28% to 69% uncertainty range) among 82 persons exposed in 1954 on Rongelap Atoll and Ailinginae Atoll, 10% (2.4% to 22%) for 157 persons exposed on Utirik Atoll, and 2.2% (0.5% to 4.8%) and 0.8% (0.2% to 1.8%), respectively, for the much larger populations exposed in mid-latitude locations including Kwajalein and in southern locations including
Majuro Majuro (; Marshallese language, Marshallese: ' ) is the Capital city, capital and largest city of the Marshall Islands. It is also a large coral atoll of 64 islands in the Pacific Ocean. It forms a legislative district of the Ratak Chain, Ratak ( ...
.


Compensation

Since 1956, the U.S. has paid at least $759 million to Marshall Islanders as compensation for their exposure to U.S. nuclear testing. Following the Castle Bravo accident on March 1, 1954, the U.S. paid $15.3 million to
Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...
. In June 1983, the U.S. and the Marshall islanders signed the
Compact of Free Association The Compacts of Free Association (COFA) are international agreements establishing and governing the relationships of free association between the United States and the three Pacific Island sovereign states of the Federated States of Micronesia ( ...
, 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 $150 million to be paid over a 15-year period ending in 2001. During that time, payments averaging about $18 million per year were made to the peoples of Bikini, Enewetak, Rongelap, and Utrik for medical and radiological monitoring, and in response to claims. The payments began in 1987 with $2.4 million paid annually to the 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 also passed the Radiation Exposure Compensation Act in 1990 to allow individuals to file claims for compensation in relation to testing as well as those employed at nuclear weapons facilities. On March 5, 2001, the Nuclear Claims Tribunal ruled against the United States for damages done to the islands and its people. The Nuclear Claims Tribunal awarded the islanders a total of $563,315,500 after deducting past awards. However, the U.S. Congress has failed to fund the settlement. The only recourse is for the Bikini people to petition the U.S. Congress to fund the payment and fulfill this award. The United States Supreme Court turned down the islanders' appeal of the United States courts of appeals decision that refused to compel the government to fund their claim. , trusts remaining from the settlement produced about US$6 to $8 million annually in investment income, and the trusts paid out about US$15,000 per family each year in benefits.


Testing chronology


Operation Crossroads (1946)

The first use of the Pacific Proving Grounds was during
Operation Crossroads Operation Crossroads was a pair of nuclear weapon tests conducted by the United States at Bikini Atoll in mid-1946. They were the first nuclear weapon tests since Trinity on July 16, 1945, and the first detonations of nuclear devices sinc ...
, the first nuclear testing done after the atomic bombing of Hiroshima and Nagasaki. Two fission bombs, both with a yield of 21 kilotons, were tested at
Bikini Atoll Bikini Atoll ( or ; Marshallese language, Marshallese: , , ), known as Eschscholtz Atoll between the 19th century and 1946, is a coral reef in the Marshall Islands consisting of 23 islands surrounding a central lagoon. The atoll is at the no ...
. "Able" was detonated at an altitude of 520 ft (158 m) on July 1, 1946, and "Baker" was detonated at a depth of 90 ft (27 m) underwater on July 25. Both tests used a flotilla of obsolete vessels from
World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...
with the intent of learning the effects of nuclear weapons on naval fleets. The "Baker" shot created a large condensation cloud and spread much more
radioactive Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is conside ...
water onto the ships than was expected; many of the surviving ships became too "hot" to be used or decontaminated and eventually had to be sunk.


Operation Sandstone (1948)

Three weapons were detonated on the
Enewetak Atoll Enewetak Atoll (; also spelled Eniwetok Atoll or sometimes Eniewetok; , , or , ; known to the Japanese as Brown Atoll or Brown Island; ) is a large coral atoll of 40 islands in the Pacific Ocean and with its 296 people (as of 2021) forms a leg ...
as part of Operation Sandstone in 1948.


Operation Greenhouse (1951)

Four weapons were detonated on the Enewetak Atoll as part of Operation Greenhouse in 1951. Two are of particular note: Greenhouse "Item" was the first use of a boosted fission weapon, and "George" was a
thermonuclear Nuclear fusion is a reaction in which two or more atomic nuclei combine to form a larger nuclei, nuclei/neutron by-products. The difference in mass between the reactants and products is manifested as either the release or absorption of ener ...
experiment designed to prove the feasibility of the
Teller-Ulam design A thermonuclear weapon, fusion weapon or hydrogen bomb (H-bomb) is a second-generation nuclear weapon design. Its greater sophistication affords it vastly greater destructive power than first-generation nuclear bombs, a more compact size, a lowe ...
for the possibility of developing
hydrogen bomb A thermonuclear weapon, fusion weapon or hydrogen bomb (H-bomb) is a second-generation nuclear weapon design. Its greater sophistication affords it vastly greater destructive power than first-generation nuclear bombs, a more compact size, a lo ...
s.


Operation Ivy (1952)

Two weapons were detonated at the Enewetak Atoll as part of Operation Ivy in 1952. One of them, Ivy King, was the largest pure-fission bomb ever detonated, with a yield of 500
kiloton TNT equivalent is a convention for expressing energy, typically used to describe the energy released in an explosion. A ton of TNT equivalent is a unit of energy defined by convention to be (). It is the approximate energy released in the det ...
s, and the other,
Ivy Mike Ivy Mike was the code name, codename given to the first full-scale test of a Thermonuclear weapon, thermonuclear device, in which a significant fraction of the explosive nuclear weapon yield, yield comes from nuclear fusion. Ivy Mike was detona ...
, was the first hydrogen bomb device (it was too large to be an actual weapon), with a yield of 10.4 Mt.


Operation Castle (1954)

Six very large nuclear tests were conducted at the
Bikini Atoll Bikini Atoll ( or ; Marshallese language, Marshallese: , , ), known as Eschscholtz Atoll between the 19th century and 1946, is a coral reef in the Marshall Islands consisting of 23 islands surrounding a central lagoon. The atoll is at the no ...
and the Enewetak Atoll as part of
Operation Castle Operation Castle was a United States series of high-yield (high-energy) nuclear tests by Joint Task Force 7 (JTF-7) at Bikini Atoll beginning in March 1954. It followed ''Operation Upshot–Knothole'' and preceded '' Operation Teapot''. Con ...
in 1954. The most notable was
Castle Bravo Castle Bravo was the first in a series of high-yield thermonuclear weapon design tests conducted by the United States at Bikini Atoll, Marshall Islands, as part of ''Operation Castle''. Detonated on 1 March 1954, the device remains the most powe ...
, which was the first deployable (dry fuel) hydrogen bomb developed by the United States. Its yield, at 15 Mt, was over twice as powerful as was predicted, and remains the largest weapon ever detonated by the United States. It spread
nuclear fallout Nuclear fallout is residual radioactive material that is created by the reactions producing a nuclear explosion. It is initially present in the mushroom cloud, radioactive cloud created by the explosion, and "falls out" of the cloud as it is ...
over a wide area, including the Enewetak Atoll, Rongerik Atoll, Ailinginae Atoll, and Rongelap Atoll. The U.S. Navy evacuated the islanders within the next few days, but many of the natives were exposed to radiation prior to evacuation. The fishermen aboard the Japanese fishing vessel '' Daigo Fukuryu Maru'' were also exposed, and one man died soon after from complications of
radiation sickness Acute radiation syndrome (ARS), also known as radiation sickness or radiation poisoning, is a collection of health effects that are caused by being exposed to high amounts of ionizing radiation in a short period of time. Symptoms can start wit ...
, resulting in considerable international controversy.


Operation Redwing (1956)

Seventeen nuclear weapons were detonated on the Bikini and Enewetak Atolls as part of Operation Redwing in 1956. Many of them were designed to prove the feasibility of numerous
thermonuclear weapon A thermonuclear weapon, fusion weapon or hydrogen bomb (H-bomb) is a second-generation nuclear weapon design. Its greater sophistication affords it vastly greater destructive power than first-generation nuclear bombs, a more compact size, a lowe ...
designs, with yields ranging from around 2 to 5 Mt.


Operation Hardtack I (1958)

Thirty-five weapons were detonated at the Bikini Atoll, Enewetak Atoll, and Johnston Island as part of Operation Hardtack I in 1958.


Operation Dominic (1962)

Thirty-six weapons were detonated at sites in the Pacific Ocean in the vicinity of
Christmas Island Christmas Island, officially the Territory of Christmas Island, is an States and territories of Australia#External territories, Australian external territory in the Indian Ocean comprising the island of the same name. It is about south o ...
and
Johnston Atoll Johnston Atoll is an Unincorporated territories of the United States, unincorporated territory of the United States, under the jurisdiction of the United States Air Force (USAF). The island is closed to public entry, and limited access for mana ...
as part of Operation Dominic I. Though these tests were not conducted in the Marshall Islands, they are officially considered part of the Pacific Proving Grounds. The portion of the Dominic series of tests that were high altitude nuclear explosions were known as Operation Fishbowl, though not all were successful (one detonated on launchpad and resulted in a substantial
plutonium Plutonium is a chemical element; it has symbol Pu and atomic number 94. It is a silvery-gray actinide metal that tarnishes when exposed to air, and forms a dull coating when oxidized. The element normally exhibits six allotropes and four ...
contamination). Two of the tests were of operational weapons systems—the ASROC anti-submarine rocket and the
Polaris Polaris is a star in the northern circumpolar constellation of Ursa Minor. It is designated α Ursae Minoris (Latinisation of names, Latinized to ''Alpha Ursae Minoris'') and is commonly called the North Star or Pole Star. With an ...
SLBM A submarine-launched ballistic missile (SLBM) is a ballistic missile capable of being launched from submarines. Modern variants usually deliver multiple independently targetable reentry vehicles (MIRVs), each of which carries a nuclear warhead ...
(the latter test, Frigate Bird, was the only operational submarine-launched ballistic missile test with a live warhead ever undertaken by the USA).


Partial Test Ban Treaty

The signing of the
Partial Test Ban Treaty The Partial Test Ban Treaty (PTBT), formally known as the 1963 Treaty Banning Nuclear Weapon Tests in the Atmosphere, in Outer Space and Under Water, prohibited all nuclear weapons testing, test detonations of nuclear weapons except for those co ...
in 1963 forbade atmospheric and underwater nuclear weapons, and so no further U.S. tests were conducted at the Pacific Proving Grounds, with all but ten occurring at the
Nevada Test Site The Nevada National Security Sites (N2S2 or NNSS), popularized as the Nevada Test Site (NTS) until 2010, is a reservation of the United States Department of Energy located in the southeastern portion of Nye County, Nevada, about northwest of ...
until the end of testing in 1992.


Geographical names

The Bikini and Enewetak Atolls are both collections of islands. Various names have been assigned to the islands over time, and confusion over the names (and their alternate transliterations) has been the source of much confusion. In addition, some islands over time have appeared, disappeared, separated, joined, and been excavated by bombs. Here are the islands listed in clockwise fashion starting with left side of the major inlet into the lagoon in each atoll. The names include the official Marshall Island names, the American military names used after occupation through the atomic testing period, and the Japanese names used while they occupied the islands during World War II, plus names gleaned from other sources.


See also

*
Nuclear weapons of the United States The United States was the first country to manufacture nuclear weapons and is the only country to have used them in combat, with the Atomic bombings of Hiroshima and Nagasaki, bombings of Hiroshima and Nagasaki in World War II against Empire o ...
* Nuclear labor issues


Explanatory notes


References


External links


"Gallery of U.S. Nuclear Tests"
at Carey Sublette's NuclearWeaponArchive.org

* ttp://www.bikiniatoll.com/ Bikini Atoll official websitebr>Republic of the Marshall Islands Nuclear Claims Tribunal
{{US Nuclear Tests American nuclear test sites Nuclear weapons infrastructure of the United States Proving grounds Bikini Atoll Enewetak Atoll Nuclear test sites Trust Territory of the Pacific Islands 1947 establishments in the United States 1947 establishments in Oceania