Runit Island () is one of forty islands of 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 ...

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 ...

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 ...

. The island is the site of a

radioactive waste Radioactive waste is a type of hazardous waste that contains radioactive material. It is a result of many activities, including nuclear medicine, nuclear research, nuclear power generation, nuclear decommissioning, rare-earth mining, and nuclear ...

repository left by the United States after it conducted a series of nuclear tests on Enewetak Atoll between 1946 and 1958. There are ongoing concerns around deterioration of the waste site and a potential radioactive spill.

Runit Dome

Construction

The Runit Dome, also called Cactus Dome or locally "the Tomb", is a diameter, thick dome of concrete at

sea level Mean sea level (MSL, often shortened to sea level) is an mean, average surface level of one or more among Earth's coastal Body of water, bodies of water from which heights such as elevation may be measured. The global MSL is a type of vertical ...

, encapsulating an estimated of radioactive debris, including some

plutonium-239 Plutonium-239 ( or Pu-239) is an isotope of plutonium. Plutonium-239 is the primary fissile isotope used for the production of nuclear weapons, although uranium-235 is also used for that purpose. Plutonium-239 is also one of the three main iso ...

. The debris stems from nuclear tests conducted in the Enewetak Atoll by the United States between 1946 and 1958. From 1977 to 1980, loose waste and topsoil from six different islands in the Enewetak Atoll was transported to the site and mixed with concrete to seal the nuclear blast crater created by the

Cactus A cactus (: cacti, cactuses, or less commonly, cactus) is a member of the plant family Cactaceae (), a family of the order Caryophyllales comprising about 127 genera with some 1,750 known species. The word ''cactus'' derives, through Latin, ...

test. Four thousand US servicemen were involved in the cleanup from this test, and it took three years to complete. The waste-filled crater was finally entombed in concrete.

Erosion

In 1982, a US government task force raised concern about a probable breach if a severe

typhoon A typhoon is a tropical cyclone that develops between 180° and 100°E in the Northern Hemisphere and which produces sustained hurricane-force winds of at least . This region is referred to as the Northwestern Pacific Basin, accounting for a ...

were to hit the island. In 2013, a report by the

US Department of Energy US or Us most often refers to: * Us (pronoun), ''Us'' (pronoun), the objective case of the English first-person plural pronoun ''we'' * US, an abbreviation for the United States US, U.S., Us, us, or u.s. may also refer to: Arts and entertainme ...

found that the concrete dome had weathered with minor cracking of the structure. However, the soil around the dome was found to be more contaminated than its contents, so a breach could not increase the radiation levels by any means. Because the cleaning operation in the 1970s only removed an estimated 0.8 percent of the total

transuranic waste Transuranic waste (TRU) is stated by U.S. regulations, and independent of state or origin, to be waste which has been contaminated with alpha emitting transuranic radionuclides possessing half-lives greater than 20 years and in concentrations g ...

in the Enewetak atoll, the soil and the lagoon water surrounding the structure now contain a higher level of

radioactivity 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 ...

than the debris of the dome itself, so even in the event of a total collapse, the radiation dose delivered to the local resident population or marine environment should not change significantly. Concern primarily lies in the rapid tidal response to the height of the water beneath the debris pile, with the potential for contamination of the groundwater supply with radionuclides. One particular concern is that, in order to save costs, the original plan to line the porous bottom crater with concrete was abandoned. Since the bottom of the crater consists of permeable soil, there is seawater inside the dome. However, as the Department of Energy report stated, the released radionuclides will be very rapidly diluted and should not cause any elevated radioactive risk for the marine environment, compared to what is already experienced. Leaking and breaching of the dome could however disperse

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 ...

, a radioactive element that is also a toxic heavy metal. An investigative report by the ''

Los Angeles Times The ''Los Angeles Times'' is an American Newspaper#Daily, daily newspaper that began publishing in Los Angeles, California, in 1881. Based in the Greater Los Angeles city of El Segundo, California, El Segundo since 2018, it is the List of new ...

'' in November 2019 reignited fears of the dome cracking and releasing radioactive material into the soil and surrounding water. The DOE was directed by Congress to assess the condition of the structure and develop a repair plan during the first half of 2020. The report was published in June 2020. In June 2020, the US Department of Energy released a report stating that the dome is in no immediate danger of collapse or breach and that the radioactive material within is not expected to have any measurable adverse effect on the surrounding environment for the next twenty years.

Illness of army personnel

Some of the US Army personnel who participated in the dome construction and transport of radioactive materials claim that illnesses that developed years later are a result of having been exposed without protection. Some of them have died of cancer and others have become sick. The US government denies that there is any connection between the work on the island and the health problems and has so far refused to offer any compensation for the illnesses associated with the construction of Runit Dome.

Gallery

File:Ivy King - mushroom cloud.jpg, In 1952, the United States dropped the nuclear bomb Ivy King 610 m (2,000 feet) north of Runit Island. File:Operation Hardtack I Cactus shot crater, Runit Island, Enewetak Atoll.jpg, Crater created by detonation on 5 May 1958 ( Operation Hardtack I, Cactus test)

References