The Nevada National Security Site (N2S2 or NNSS), known as the Nevada Test Site (NTS) until 2010, is a United States Department of Energy (DOE) reservation located in southeastern Nye County, Nevada, about 65 miles (105 km) northwest of the city of Las Vegas. Formerly known as the Nevada Proving Grounds, the site was established in 1951 for the testing of nuclear devices. It covers approximately 1,360 square miles (3,500 km2) of desert and mountainous terrain. Nuclear weapons testing at the site began with a 1-kiloton (4.2 TJ) bomb dropped on Frenchman Flat on January 27, 1951. Over the subsequent four decades, over 1,000 nuclear explosions were detonated at the site. Many of the iconic images of the nuclear era come from the site.
During the 1950s, the mushroom clouds from the 100 atmospheric tests could be seen from almost away. The city of Las Vegas experienced noticeable seismic effects, and the mushroom clouds, which could be seen from the downtown hotels, became tourist attractions. Westerly winds routinely carried the fallout from above-ground nuclear testing directly through St. George, Utah and southern Utah. Increases in cancers, such as leukemia, lymphoma, thyroid cancer, breast cancer, melanoma, bone cancer, brain tumors, and gastrointestinal tract cancers, were reported from the mid-1950s onward. A further 828 nuclear tests were carried out underground.
From 1986 through 1994, two years after the United States put a hold on full-scale nuclear weapons testing, 536 anti-nuclear protests were held at the site, involving 37,488 participants and 15,740 arrests, according to government records.
The site contains 28 areas, 1,100 buildings, 400 miles (640 km) of paved roads, 300 miles of unpaved roads, 10 heliports, and two airstrips.
Currently, Mission Support and Test Services (MSTS) is the civilian contractor for the site's management and oversees overall operations. MSTS manages and operates the site for the National Nuclear Security Administration (NNSA). Security is provided by SOC LLC. MSTS is a joint venture of Honeywell International Inc., Jacobs Engineering Group Inc., and HII Nuclear, Inc.
History
The site was established as a area by President Harry S. Truman on December 18, 1950, within the Nellis Air Force Gunnery and Bombing Range.
1951–1992
The site was the primary testing location of American nuclear devices from 1951 to 1992; 928 announced nuclear tests occurred there. Of those, 828 were underground. (Sixty-two of the underground tests included multiple, simultaneous nuclear detonations, adding 93 detonations and bringing the total number of NTS nuclear detonations to 1,021, of which 921 were underground.) The site contains many subsidence craters from the testing.
The site was the United States' primary location for tests smaller than . 126 tests were conducted elsewhere, including most larger tests. Many of these occurred at the Pacific Proving Grounds in the Marshall Islands.
During the 1950s, the mushroom clouds from atmospheric tests could be seen for almost . The city of Las Vegas experienced noticeable seismic effects, and the distant mushroom clouds, which could be seen from the downtown hotels, became tourist attractions. The last atmospheric test detonation at the site was "Little Feller I" of Operation Sunbeam, on July 17, 1962.
Although the United States did not ratify the Comprehensive Nuclear-Test-Ban Treaty, it honors the articles of the treaty, and underground testing of weapons ended as of September 23, 1992. Subcritical tests not involving a critical mass continued.
One notable test shot was the "Sedan" shot of Operation Storax on July 6, 1962, a shot for Operation Plowshare, which sought to prove that nuclear weapons could be used for peaceful means in creating bays or canals. It created a crater 1,280 feet (390 m) wide and 320 feet (100 m) deep.
1992–present
More than 27 subcritical tests have been conducted at the site
In 2018, the State of Nevada sued the federal government to block a plan to ship "more than a metric ton" of plutonium to the site for temporary storage.
In 2022, the government acknowledged that 13,625 cubic meters of radioactive material conforming to its disposal criteria had been shipped to the site for disposal.