From the Amchitka Fact Sheet: (Amchitka Fact Sheet)
“The U.S. government conducted three underground nuclear
tests on Amchitka; the U.S. Department of Defense and the
U.S. Atomic Energy Commission (AEC), a predecessor of
the U.S. Department of Energy (DOE) jointly conducted the
first two, and AEC conducted the third. The first test, named
Long Shot, was a nuclear detection research experiment
detonated in October 1965 at a depth of 2,297 feet below
ground surface, with a yield of 80 kilotons (TNT equivalent).
The second test, Milrow, was a high-yield (about 1 megaton)
weapons calibration test detonated in October 1969 at a
depth of 4,003 feet. The third test, known as Cannikin,
was detonated in November 1971 at a depth of 5,873 feet (1.1 mile) below ground surface, with a yield of less than 5 megatons.
Cannikin remains the largest underground nuclear test in
U.S. history.” https://www.energy.gov/sites/default/files/2022-09/AmchitkaFactSheet.pdf
“Amchitka was easily one of the most remote and inhospitable U.S. military outposts of World War II. It was so remote that during the Cold War, the U.S. detonated three nuclear warheads on the island in various underground tests. Located about 80 miles from Kiska Island in the Aleutian chain, American forces landed there unopposed in January 1943 and quickly built an airfield there to support the final stages of the campaign in the far north. Once the Japanese had been driven from Attu and Kiska, Amchitka-based Navy patrol bombers and 11th AF aircraft began periodic attacks on the Japanese Kurile Islands.” https://theamericanwarrior.com/2014/11/27/thanksgiving-on-amchitka/
“In 1965, the US conducted the first nuclear explosion on Amchitka. An 80-kiloton nuclear blast was set off underground. Scientists used this blast for research purposes. It was analyzed by seismologists to help determine whether other countries were conducting underground nuclear testing.
A second blast was set off in 1969, 4,000 feet below the surface of Amchitka. This exercise was used to understand how larger underground explosions “might damage the island, trigger seismic activity, or generate tsunamis. Workers drilled a 4,000-foot hole.”
The most notorious explosion was conducted in 1971, “Project Cannikin.” At 5-megatons, this blast was 250 times more powerful than the bomb dropped on Hiroshima. It was detonated almost a mile below Amchitka’s surface. The detonation caused the ground surface on Amchitka to rise, then fall 20 feet. A crater a mile wide and 40 feet deep on Amchitka’s surface serves as an ominous reminder of the massive explosion. The shock from the explosion measured 7.0 on the Richter scale, the same as the 2010 earthquake that devastated Haiti. A social movement against Project Cannikin by a group of environmentalists from British Columbia inspired the formation of the group Greenpeace.”
“Bob Hunter sailed aboard the first Greenpeace voyage in 1971 to Amchitka in the Aleutian Islands to try and stop a U.S. nuclear weapons test. When they were halfway to their destination, Richard Nixon announced a month’s delay of the test. Most of the crew were running out of money or vacation time, and an acrimonious debate broke out about whether to continue or turn back. This is Bob’s story about what happened.”
“When I got back from the expedition to Amchitka and sat down to write a book about it, I was convinced we had lost, and I was angry. The best chance ever to actually interfere with nuclear testing, and we had blown it through sheer stupidity – and a failure of nerve, to put it kindly. Cop-out on the Way to Amchitka was the title that loomed in my mind. And my personal failure of will was a big factor in that cop-out. Worse, I was afraid that I’d subconsciously thrown the fight to carry on with the voyage. I’d have to live with that until I died or the world blew up, whichever happened first.” https://www.greenpeace.org/international/story/46686/amchitka-the-founding-voyage/
“No Sea Otters were injured in the nuclear test,” LOL!
“Contractor scientists for the U.S. Department of Energy Office of Legacy Management (LM) traveled to the Amchitka, Alaska, Site in late August to assess the damage caused by a recent earthquake. The 7.9 magnitude event occurred approximately 20 miles north of the island on June 23, 2014. Amchitka Island, near the western end of the Aleutian Islands, is approximately 1,300 miles southwest of Anchorage, Alaska.”
“Although there was shaking-induced ground failure at the surface, primarily in areas with soft, wet sediments and fill, [we] don’t suspect any damage occurred in the test cavities,” said Mark Kautsky, LM site manager. “The test cavities are in dense rock, several thousand meters below the surface and the earthquake occurred at a depth of 70 miles below the surface, so it is unlikely there was any damage to the underground test cavities; however, we will continue monitoring the region very closely.”
As of 07/19/2015, the total compensation paid under Parts B and E of the EEOICPA, including medical compensation, for workers suffering from the effects of having worked at Amchitka Island Nuclear Explosion Site is $95,431,629.