Amchitka Amchitka ( ; ) is a volcanic , tectonically unstable island in the Rat Islands group of the Aleutian Islands in southwest Alaska . It is part of the Alaska Maritime National Wildlife Refuge . The island is about long , and from wide . The area has a maritime climate , with many storms , and mostly overcast skies . Amchitka was populated for more than 2 , 500 years by the Aleut people , but has had no permanent population since 1832 . The island has been part of the United States since the Alaska Purchase of 1867 . During World War II , it was used as an airfield by US forces in the Aleutian Islands Campaign . Amchitka was selected by the United States Atomic Energy Commission to be the site for underground detonations of nuclear weapons . Three such tests were carried out : " Long Shot " , an blast in 1965 ; " Milrow " , a blast in 1969 ; and " Cannikin " in 1971 – at , the largest underground test ever conducted by the United States . The tests were highly controversial , with environmental groups fearing that the " Cannikin " explosion , in particular , would cause severe earthquakes and tsunamis . Amchitka is no longer used for nuclear testing . It is still monitored for the leakage of radioactive materials . Geography . Amchitka is the southernmost of the Rat Islands group in the Aleutian Chain , located between and . It is bounded by the Bering Sea to the north and east , and the Pacific Ocean to the south and west . The eastern part of the island is a lowland plateau , with isolated ponds and gently rolling hills . There is low but abundant vegetation , consisting of mosses , lichens , liverworts , ferns , grasses , sedges , and crowberry . The center of the island is mountainous , and the western end is barren and vegetation is sparse . Amchitka has a maritime climate , often foggy and windswept , with cloud cover 98 percent of the time . While temperatures are moderated by the ocean , storms are frequent . Geologically , the island is volcanic , being a part of a small crustal block on the Aleutian Arc that is being torn apart by oblique subduction . It is " one of the least stable tectonic environments in the United States . " Early history . The human history of Amchitka dates back at least 2 , 500 years , with the Aleut people . Human remains , thought to be of an Aleut dating from about 1000 AD , were discovered in 1980 . Amchitka is said to have been seen and named St . Makarius by Bering in 1741 , was sighted by Billings in 1790 , and visited by Shishmaref in 1820 . In 1783 , Daikokuya Kōdayū and 15 Japanese castaways landed on Amchitka after drifting for seven months . The castaways were taken care of by Russian employees of Zhigarev and hunted with indigenous people . Six of the castaways died in three years . According to Kōdayū , islanders received necessities and supplies such as tobacco , ironware , horse - and ox - skins , and cotton in return for hunting otters or seals . The furs brought by indigenous people were divided into thirds between the Russian Empire , Moscow furrier Vassily Yakovlevich Zhigarev ( mayor of Moscow in 1795 - 1798 ) , and Zhigarev ' s Russian employees . Russian trappers and traders established settlements on the islands , exploiting the indigenous people , whose population on the island quickly fell . In 1784 , a major Aleut revolt occurred as Russians killed Oniishin , indigenous chieftain ' s daughter and the Russian chief ' s mistress ( See : " Aleut people # Recorded revolt " ) , and hundreds of Aleuts escaped from Amchitka after being defeated by five Russians . From 1832 , the island was never permanently inhabited . The islands were surveyed by the North Pacific Exploring Expedition in 1855 , and were included in the Alaska Purchase of 1867 . In 1913 , President William Howard Taft set aside the Aleutian chain , including Amchitka , as a wildlife preserve . The Native residents of Atka leased the island for fox hunting in 1920 , and continued to use the island until the Japanese invasion of the western Aleutians in 1942 . By the time of World War II , an abandoned Russian fishing village was all that remained . World War II . In June 1942 , the Japanese occupied some of the western Aleutian islands , and hoped to occupy Amchitka . Eager to remove the Japanese , the Joint Chiefs of Staff agreed to move quickly to regain the territory . American planners decided to build a series of airfields to the west of Umnak , from which bombers could attack the invading forces . The U . S . Army established bases at Adak and 13 other locations . At the War Department ' s suggestion , an initial reconnaissance of Amchitka was carried out in September 1942 , which found that it would be difficult to build an airstrip on the island . Nevertheless , planners decided on December 13 that the airfield " had to be built " to prevent the Japanese from doing the same . A further reconnaissance mission visited Amchitka from 17 to 19 December , and reported that a fighter strip could be built in two to three weeks , and a main airfield in three to four months . The plan was approved and began in 1942 . American forces made an unopposed landing on Amchitka on January 12 , 1943 , although the destroyer grounded and sank with the loss of 14 lives . Despite facing difficult weather conditions and bombing from the Japanese , the airfield was usable by February 16 . The Alaska Command was now away from their target , Kiska . The military eventually built numerous buildings , roads , and a total of three airstrips on the island , one of which would later be rebuilt and used by the Atomic Energy Commission in the late 1960s . At its peak , the occupancy of Amchitka reached 15 , 000 troops . The Aleutian Islands campaign was successfully completed on August 24 , 1943 . In that month , a strategic intercept station was established on the island , which remained until February 1945 . On 31 December 1949 the Air Force Base was closed due to insufficient personnel and staff . The Army closed its communications facility at Amchitka in August 1950 . On 31 December 1950 the Air Force 2107th Air Weather Group pulled the last of its personnel out of Amchitka and the facility was abandoned . The site later hosted an Air Force White Alice telecommunication system in 1959 to 1961 , and a temporary relay station in the 1960s and 1970s . Plans for nuclear testing . With the pullout of military forces from Amchitka in 1950 , the Department of Defense initially considered the island for nuclear testing planned for 1951 . Requiring information about the cratering potential of nuclear weapon s , plans were made to detonate two devices . After approximately 34 test holes had been drilled , the site was deemed unsuitable , and the project was moved to the Nevada test site . In the late 1950s , scientists realized that improved seismological knowledge was necessary for the detection of Soviet underground nuclear explosions . The " " Rainier " " test ( part of Operation Plumbbob , performed in Nevada ) produced strong seismic signals , but looked much like an ordinary earthquake . In 1959 , Dr . James R . Killian , the Special Assistant to the President for Science and Technology , formed the Panel on Seismic Improvement ( which subsequently recommended the program that came to be known as Vela Uniform ) , with the twin goals of improving seismic instruments and deploying them globally , and researching in more depth the seismic effects of nuclear explosions . The project was subsequently initiated by the Eisenhower administration . Together with the Atomic Energy Commission , the DoD began assessing Amchitka for use as part of the " Vela Uniform " tests . Long Shot test . To conduct the Vela Uniform test " Long Shot " , the Department of Defense occupied Amchitka from 1964 to 1966 , with the AEC providing the device , measuring instruments , and scientific support . The goal was " to determine the behavior and characteristics of seismic signals generated by nuclear detonations and to differentiate them from seismic signals generated by naturally occurring earthquakes . " Although it would not be publicly announced until March 18 , 1965 , senior Alaskan officials were notified the previous February . After the devastating Great Alaska Earthquake of March 27 , 1964 , the governor expressed concern about the psychological effects of the test on the populace . He was quickly reassured . " Long Shot " was detonated on October 29 , 1965 , and the yield was . It was the first underground test in a remote area , and the first test managed by the DoD . While there was no surface collapse , tritium and krypton were found at the surface following the test ; this was not made public until 1969 . Milrow and Cannikin tests . Though performed as part of the Nuclear Weapons Testing Program , " [ the ] purpose of the " Milrow " test was to test an island , not a weapon . " It was a " calibration shot " , intended to produce data from which the impact of larger explosions could be predicted , and specifically , to determine whether the planned " Cannikin " detonation could be performed safely . " Milrow " was detonated on October 2 , 1969 , with an approximate yield of . The shockwave reached the surface with an acceleration of over 35 g ( 340 m / s ) , causing a dome of the Earth ' s surface , approximately in radius , to rise about . The blast " turned the surrounding sea to froth " and " forced geysers of mud and water from local streams and lakes into the air " . A " surface collapse feature " , also known as a subsidence crater , was formed by material collapsing into the cavity formed by the explosion . " Cannikin " was intended to test the design of the Spartan anti - ballistic missile ( ABM ) interceptor – a high - yield warhead that " produced copious amounts of x - rays and minimized fission output and debris to prevent blackout of ABM radar systems . " The test would " measure the yield of the device , measure the x - ray flux and spectrum , and assure deployment of a reliable design . " Controversy . A few days after the " Milrow " test , the Don ' t Make A Wave Committee was organized at a meeting in Vancouver . On the agenda was whether to fight another blast at the island , or whether to expand their efforts to fight all perceived threats against the environment . As he was leaving , one man gave the traditional farewell of the peace - activist movement , " Peace . " " Make it a green peace . " replied another member . The Committee would later become Greenpeace . The Committee ' s name referred to predictions made by a Vancouver journalist named Bob Hunter , later to become Greenpeace member 000 . He wrote that the test would cause earthquakes and a tsunami . The AEC considered the likelihood of the test triggering a severe earthquake " very unlikely " , unless one was already imminent on a nearby fault , and considered a tsunami " even more unlikely " . Others disagreed . Russell Train , then Chairman of the Council on Environmental Quality , argued that " experience with " Milrow " . . . does not provide a sure basis for extrapolation . In the highly nonlinear phenomena involved in earthquake generation , there may be a threshold value of the strain that must be exceeded prior to initiation of a large earthquake . . . . The underground explosion could serve as the first domino of the row of dominoes leading to a major earthquake . . . . as in the case of earthquakes it is not possible at this time to assess quantitatively the probability of a tsunami following the explosion . " In July 1971 , a group called the " Committee for Nuclear Responsibility " filed suit against the AEC , asking the court to stop the test . The suit was unsuccessful , with the Supreme Court denying the injunction by 4 votes to 3 , and Richard Nixon personally authorized the $ 200 million test , in spite of objections from Japan , Peru , and Sweden . " What the Court didn ’ t know , however , was that six federal agencies , including the departments of State and Interior , and the fledgling EPA , had lodged serious objections to the Cannikin test , ranging from environmental and health concerns to legal and diplomatic problems . Nixon issued an executive order to keep the comments from being released . " The " Don ' t Make A Wave Committee " chartered a boat , in which they had intended to sail to the island in protest , but due to weather conditions they were unable to reach their destination . Cannikin tested . " Cannikin " was detonated on November 6 , 1971 , as the thirteenth test of the Operation Grommet ( 1971 – 1972 ) underground nuclear test series . The announced yield was 5 megatons ( 21 PJ ) – the largest underground nuclear test in US history . ( Estimates for the precise yield range from 4 . 4 to 5 . 2 megatons or 18 to 22 PJ ) . The ground lifted , caused by an explosive force almost 400 times the power of the Hiroshima bomb . Subsidence and faulting at the site created a new lake , over a mile wide . The explosion caused a seismic shock of 7 . 0 on the Richter scale , causing rockfalls and turf slides of a total of . Though earthquakes and tsunamis predicted by environmentalists did not occur , a number of small tectonic events did occur in the following weeks , ( some registering as high as 4 . 0 on the richter scale ) thought to be due to the interaction of the explosion with local tectonic stresses . According to wildlife surveys following the " Cannikin " event by the University of Alaska Fairbanks , 700 – 2 , 000 sea otters were killed by overpressure s in the Bering Sea as a direct result of the explosion . This survey showed that number of sea otters endangered by the blast was far greater than the Atomic Energy Commission had predicted . 1973 and beyond . The AEC withdrew from the island in 1973 , though scientists continue to visit the island for monitoring purposes . In 2001 , the DoE returned to the site to remove environmental contamination . Drilling mud pits were stabilized by mixing with clean soil , covering with a polyester membrane , topped with soil and re - seeded . Concerns have been expressed that new fissures may be opening underground , allowing radioactive materials to leak into the ocean . A 1996 Greenpeace study found that " Cannikin " was leaking both plutonium and americium into the environment . In 2004 , scientific divers from the University of Alaska Fairbanks collected shallow subtidal organisms and reported that " There were no indications of any radioactive leakage , and all that was really wonderful news . " Similar findings are reported by a 2006 study , which found that levels of plutonium " were very small and not significant biologically " . The Department of Energy continues to monitor the site as part of their remediation program . This is expected to continue until 2025 , after which the site is intended to become a restricted access wildlife preserve .