Nevada Test Site

The Nevada National Security Site (NNSS; N2S2) initially named the Nevada Proving Ground (1951–1955), and later the Nevada Test Site (NTS; 1955–2010)) is a reservation of the United States Department of Energy located in the southeastern portion of Nye County, Nevada, approximately northwest of Las Vegas.

The site was established in December 1950 when President Harry S. Truman authorized the designation of a portion of the Nellis Air Force Gunnery and Bombing Range for testing American nuclear devices by the US Atomic Energy Commission (AEC).

The first atmospheric test was conducted at the site's Frenchman Flat area by the AEC on January 27, 1951. About 928 nuclear tests were conducted here through 1992, when the United States stopped its underground nuclear testing.

The site consists of about of desert and mountainous terrain. Some 1,100 buildings in 28 areas are connected by of paved roads, of unpaved roads, ten heliports, and two airstrips. The site is privately managed and operated by Mission Support and Test Services LLC, a joint venture of Honeywell, Jacobs, and Huntington Ingalls, on behalf of the National Nuclear Security Administration (NNSA).

The mushroom clouds from the 100 atmospheric tests were visible from almost away; they could be seen from the Las Vegas Strip in the early 1950s. Many iconic images at nuclear science museums throughout the United States come from the site. Las Vegas experienced noticeable seismic effects. Westerly winds routinely carried the fallout from atmospheric nuclear tests, increasing rates of cancer in Utah and elsewhere, according to a 1984 medical report.

The site has hosted 536 publicized and organized anti-nuclear protests, with 37,488 participants and 15,740 involved in arrests, according to government records.

History

thumb|250px|A map that details the [[Federal lands|federal land in southern Nevada, showing the site]]

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

thumb|upright|This handbill was distributed 16 days before the first nuclear device was detonated at the site.

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 (62 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 . One hundred twenty-six tests were conducted elsewhere, including most larger tests. Many of these occurred at the Pacific Proving Grounds in the Marshall Islands.

thumb|Mushroom cloud seen from [[downtown Las Vegas.]]

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.

thumb|[[Sedan crater]]

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.

Destruction and survivability testing

right|thumb|This model two-story house was constructed away from the ground-zero of the [[Apple-2 nuclear test.]] Testing of the various effects of detonation of nuclear weapons was carried out during above-ground tests. Many kinds of vehicles (ranging from cars to aircraft), nuclear-fallout and standard bomb-shelters, public-utility stations and other building structures and equipment were placed at measured distances away from "ground zero", the spot on the surface immediately under or over the center of the blast. Operation Cue tested civil defense measures. Such civilian and commercial effects testing was done with many of the atomic tests of Operation Greenhouse on Eniwetok Atoll, Operation Upshot-Knothole and Operation Teapot at the site.

Homes and commercial buildings of many different types and styles were built to standards typical of American and (less-often) European cities. Other such structures included military fortifications (of types used by both NATO and the Soviet-led Warsaw Pact) and civil-defense as well as "backyard"-type shelters. In such a typical test, several of the same buildings and structures might be built using the same layouts and plans with different types of materials, paints, general landscaping, cleanliness of the surrounding yards, wall-angles or varying distances from ground zero. Mannequins were placed in and around the test vehicles and buildings, aside from some left out in the open, for testing clothing and shock effects.

High-speed cameras were placed in protected locations to capture effects of radiation and shock waves. Typical imagery from these cameras shows paint boiling off the buildings, which are then pushed violently away from ground zero by the shock wave before being drawn toward the detonation by the suction caused by the climbing mushroom cloud. Footage from these cameras has become iconic, used in various media and available in the public domain.

This testing allowed the development of Civil Defense guidelines, distributed to the public, to increase the likelihood of survival in case of air- or spaceborne nuclear attack.

Environmental impact

Each of the below-ground explosions—some as deep as 5,000 feet (1.5 km)—vaporized a large chamber, leaving a cavity filled with radioactive rubble. About a third of the tests were conducted directly in aquifers, and others were hundreds or thousands of feet below the water table.

When underground explosions ended in 1992, the Department of Energy estimated that more than of radioactivity remained in the environment at that time, making the site one of the most contaminated locations in the United States. In the most seriously affected zones, the concentration of radioactivity in groundwater reaches millions of picocuries per liter. (The federal standard for drinking water is 20 picocuries per liter (0.74 Bq/L).) Although radioactivity levels in the water continue to decline over time, the longer-lived isotopes like plutonium or uranium could pose risks for thousands of years.

The DOE issues an annual environmental monitoring report containing data from the monitoring wells both on and off site.

Protests and demonstrations

thumb|upright|Members of [[Nevada Desert Experience|Desert Lenten Experience hold a prayer vigil during the Easter period of 1982 at the entrance to the site.]]

In 1983, four Greenpeace activists made the first incursion into the site of an active test. Two American men, one from West Germany and one from the United Kingdom hiked 30 miles on foot to hide in the desert near ground zero at Yucca Flats. The four evaded capture for a week with the stated objective of delaying the test, and were charged with trespassing.

From 1986 through 1994, two years after the United States ended nuclear weapons testing, 536 demonstrations were held at the site involving 37,488 participants and 15,740 arrests, according to government records.

On February 5, 1987, more than 400 people were arrested trying to enter the site after nearly 2,000 demonstrators held a rally to protest nuclear weapons testing. Those arrested included the astronomer Carl Sagan and the actors Kris Kristofferson, Martin Sheen, and Robert Blake. Five Democratic members of Congress attended the rally: Thomas J. Downey, Mike Lowry, Jim Bates, Leon E. Panetta, and Barbara Boxer.

American Peace Test (APT) and Nevada Desert Experience (NDE) held most of these. In March 1988, APT held an event where more than 8,000 people attended a ten-day action to "Reclaim the Test Site", where nearly 3,000 people were arrested, including more than 1,200 in one day. This set a record for most civil disobedience arrests in a single protest.

On October 12, 1992, an 11-day protest took place at the Test Site. At the invitation of the Western Shoshone Tribe and Corbin Harney, an anti-nuclear activist and spiritual leader for the Newe people, over 2,000 protesters from 12 different countries gathered for "Healing Global Wounds". In their media work, protesters and organizers demanded an end to nuclear weapons testing and return of the test site to the Western Shoshone people. Camped in the desert, participants took part in anti-racism and peaceful civil disobedience trainings. They planned actions and demonstrations, eventually using culverts and other means to enter the Test Site where 530 were arrested by Wackenhut Security forces on charges of trespassing. Full-scale nuclear weapons testing did not resume.

After 1994, Shundahai Network in cooperation with Nevada Desert Experience and Corbin Harney continued the protests of the work at the site and staged efforts to stop a repository for highly radioactive waste adjacent to the test site at nearby Yucca Mountain.

Modern usage

thumb|[[Weapon of mass destruction|WMD/counter-terrorism training exercise at the site.]]

The site continues to be used for nuclear weapons research and development. This includes subcritical testing. These tests are conducted jointly by Los Alamos National Laboratory, Lawrence Livermore National Laboratory, and the British Atomic Weapons Establishment. A recent one was Ediza (2019), and Nightshade A (2020).

The site offers monthly public tours, often booked months in advance. Visitors are not allowed to bring cameras, binoculars, or cell phones, nor are they permitted to pick up rocks for souvenirs.

While there are no longer any explosive tests of nuclear weapons at the site, there is still testing done to determine the viability of the United States' aging nuclear arsenal. Additionally, the site is the location of the Area 5 Radioactive Waste Management Complex, which sorts and stores low-level radioactive waste that is not transuranic and has a half-life of less than 20 years.

The Radiological/Nuclear WMD Incident Exercise Site (T-1) replicates multiple terrorist radiological incidents with train, plane, automobile, truck, and helicopter props. It is located in Area 1, at the former site of tests EASY, SIMON, APPLE-2, and GALILEO.

Landmarks and geography

A table of interesting places in and around the NNSS is presented here, which corresponds with many of the descriptions in the Nevada Test Site Guide.

{| class="wikitable sortable"

|+Interesting locations in the NNSS

! Name

! Location

! Notes

! Mercury

| Area 23

| The base housing and office area for the site.

! Principal Underground Laboratory for Subcritical Experimentation (PULSE), formerly known as U1a

| Area 1

| PULSE, formerly known as U1a, is an underground laboratory used for physics experiments that obtain technical information about the U.S. nuclear weapons stockpile. U1h and U1g, shafts which add data access, ventilation and other utilities to the facility, are just north of this entrance.

! Industrial area

| Area 1

| Houses $20 million worth of mining tools; contains an area for creating site grout and stemming mixes.

! Doomtown

| Area 5

| The original effects test area and close cousin to Survival City in Area 1.

! EPA's NTS Dairy

| Area 15

| A dairy and pig farm maintained from 1964 to 1984 by the EPA, mainly to provide experimental data for uptake of milk contamination, following Operation Schooner.

! Yucca Mountain nuclear waste repository

| Area 25

| Yucca Mountain radioactive disposal site. This is the north entrance; the south entrance is about SSW.

! A Tunnel

| Area 16

| Shoshone Mountain, Tunnel A Entrance.

! B Tunnel

| Area 12

| Rainier Mesa, Tunnel B Entrance.

! C, D, and F Tunnels

| Area 12

| Rainier Mesa, tunnels C, D, and F Entrances – separate, but very close together.

! E Tunnel

| Area 12

| Rainier Mesa, Tunnel E Entrance.

! G Tunnel

| Area 12

| Rainier Mesa, Tunnel G Entrance.

! I Tunnel

| Area 12

| Rainier Mesa, Tunnel I Entrance.

! J Tunnel

| Area 12

| Rainier Mesa, Tunnel J Entrance.

! K Tunnel

| Area 12

| Rainier Mesa, Tunnel K Entrance.

! N Tunnel

| Area 12

| Rainier Mesa, Tunnel N Entrance.

! P Tunnel

| Area 12

| Rainier Mesa, Tunnel P Entrance.

! T Tunnel

| Area 12

| Rainier Mesa, Tunnel T Entrance.

! X Tunnel

| Area 25

| Two tunnel entrances, used by the U.S. Army Ballistic Research Laboratory for depleted uranium testing.

! Operation Icecap

| Area 7

| Operation Icecap was being built up when the 1992 Comprehensive Test Ban was signed. The equipment was left in place, including the instrumentation payload, the crane, the wiring, and many of the recording trailers.

! Operation Gabbs

| Area 2

| Operation Gabbs was another shaft detonation scheduled for 1993 that was laid to rest by the '92 test ban treaty.

! Operation Greenwater

| Area 20

| The third suspended test was Operation Greenwater, the test of the space X-Ray laser system, a part of the Star Wars concept. The tower remains on the site.

! Survival City

| Area 1

| The alternative to Doomtown. Used in the Teapot Desert/Rock exercises, and the Civil Defence/PR effort Operation Cue. Name taken from "News of the Day" newsreel about the Apple 2 test.

! Fortune Training Area

| Area 1

| Fortune was a training facility for building bomb test sites. Site reused for Unicorn test in 2005–06.

! Divine Strake

| Area 16

| U16b tunnel entrance complex, including Divine Strake proposed 700t chemical blast tunnel on the north, the latter heavily protested, delayed, and eventually abandoned.

! Plutonium Valley

| Area 11

| Area contains scattered raw plutonium from plutonium dispersal safety tests.

! Original BREN Tower

| Area 4

| Original site of the Bare Reactor Experiment in Nevada (BREN), a reactor on a tower which emulated bomb explosions for medical studies. A Japanese village was constructed around it because it focused on war bomb injuries. BREN was later moved to Area 25.

! BREN Tower

| Area 25

| The BREN (Bare Reactor Experiment, Nevada) is a tall tower originally in Yucca Flat, used to experimentally irradiate ground targets with gamma and neutrons. Moved to Jackass Flat, for HENRE (High Energy Neutrons Action Experiment) and demolished in 2012.

! Nerva Test Stand

| Area 25

| Test stand for the "Nerva" nuclear rocket.

! KIWI-TNT

| Area 25

| Test of the Nerva engine to destruction, to determine worst-case scenario for runaway reactor. 1.6 Mci released.

! DAF

| Area 6

| Device Assembly Facility: bombs and components are made ready for testing here.

! RWMS-5

| Area 5

| Radioactive Waste Management Facility, Area 5

! E-MAD Building

| Area 25

| Engine Maintenance and Disassembly Building, used for handling radioactive NERVA engines; site being dismantled.

! R-MAD Building

| Area 25

| Reactor Maintenance and Disassembly Building, maintained radioactive NERVA reactors. Also used in the MX program; site being dismantled.

! ETS-1 Test Stand

| Area 25

| Engineering Test Stand 1, a stand for testing nuclear rockets in a standard upright position.

! MX Testing Area

| Area 25

| MX missile test track and silo

! JASPER

| Area 27

| Houses the Joint Actinide Shock Physics Experimental Research, a two-stage light-gas gun for shock experiments.

! Camp 12

| Area 12

| Camp for miners and others working on the Rainier Mesa in the '70s.

! BEEF

| Area 4

| Big Explosives Experimental Facility. Explosive testing facility utilized by Los Alamos National Laboratory personnel deployed to the NNSS.

! Area 3 RWMS

| Area 3

| Low level Radioactive Waste Management Facility. Waste (mostly dirt) is buried in a selection of old subsidence craters.

! Atlas Pulse Power

| Area 6

| The Atlas Pulse Power Facility

! Apple-2 houses

| Area 1

| Three "typical American" houses built for the Apple-2 civil defense event. The one on the left is from the 29kt blast, the right one . The left one is on the monthly tour bus route. The two towers are from later seismic studies.

! News Nob

| Area 6

| The location from which VIPs and news people would watch nuclear tests.

! Annie Emplacement

| Area 5

| Location of "Atomic Annie" (M65 280mm nuclear field artillery) emplacement for Upshot-Knothole Grable test.

! BACHUS Site

| Area 12

| Biotechnology Activity Characterization by Unconventional Signatures, a biowarfare simulation facility.

! Rad/NucCTEC

| Area 6

| Radiological/Nuclear Countermeasures Test and Evaluation Complex Homeland Security operational nuclear test and training center

! Project Pluto

| Area 26

| Ram-jet nuclear-powered cruise missile engine development project; site being dismantled.

! Lockheed-Martin AOF

| Area 6

| Aerial Operations Facility; a testing area for UAVs.

! Camp Desert Rock

| Area 22

| The Army Camp that housed the participants in Operations Desert Rock I-VIII. Across the road is the Pig Hilton, where test subjects were housed.

! Test Control Point

| Area 6

| NTS Test control center (CP-1). These two buildings controlled the tests performed at the site.

! NNSS-CTOS

| Area 1

| Counter Terrorism Operations Support, a location for training in emergency preparedness in radiological emergencies.

! Super Kukla

| Area 27

| A naked reactor test area designed to test equipment under a hostile radioactive environment, 1965–78.

! Bleachers

| Area 5

| Bleacher area for viewing of Frenchman Flat events.(14 Atmospheric Tests)

! BODF

| Area 4

| Buried Objects Detection Facility, area to test and calibrate mine sweeping equipment against buried objects.

! Gun Turret USS Louisville

| Area 2

| Used in calibration of Whitney, Shasta, Diablo and Smoky tests. Made of "old" steel from 1940s U.S. heavy cruiser (USS Louisville CA 28) damaged from kamikaze on January 5, 1945; it was "aimed" at the shot cab to get radiation data.

! Hazmat Spill Facility

| Area 5

| Hazmat Spill Test Facility – used to test Hazmat strategies and tactics. Became the Nonproliferation Test and Evaluation Complex in 2005.

! RBIFF

| Area 26

| Re-entry Body Impact Fuze Flights

! Ship of the Desert

| Area 5

| A massive tracked structure designed to capture neutrons from the Diagonal Line experiment.

! Rock Valley Study

| Area 25

| The circles are the Rock Valley Study Area, environmental research area for studying radiation in the desert ecosystem.

! Climax Mine

| Area 15

| Location of an old silver mine, recycled for three nuclear tests and the Spent Fuel Test in which spent nuclear fuel was stored in a mine drift to study the effects on the granite walls.

! The Forest

| Area 5

| The famous forest on the desert, swept by the blasts of Encore and Grable.

!The House in the Middle

|Area 5

|1954 short documentary from the Encore test. A clean, freshly painted house might save your home in a nuclear attack.

Cancer and test site

thumb|right|300px|[[Iodine-131 fallout exposure in rads]]

Many communities east of the Nevada Test Site, including Cedar City, Enterprise, and St. George, Utah, received fallout from above-ground nuclear testing in the Yucca Flats at the site. Winds routinely carried the fallout of these tests directly through St. George and southern Utah. Marked 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 through 1980.

A 1962 United States Atomic Energy Commission report found that "children living in St. George, Utah may have received doses to the thyroid of radioiodine as high as 120 to 440 rads" (1.2 to 4.4 Gy). A 1979 study reported in the New England Journal of Medicine concluded that:

<blockquote>A significant excess of leukemia deaths occurred in children up to 14 years of age living in Utah between 1959 and 1967. This excess was concentrated in the cohort of children born between 1951 and 1958, and was most pronounced in those residing in counties receiving high fallout.</blockquote>

In 1982, a lawsuit brought by nearly 1,200 people accused the government of negligence in atomic and/or nuclear weapons testing at the site, which they said had caused leukemia and other cancers. Dr. Karl Z. Morgan, Director of Health Physics at Oak Ridge National Laboratory, testified that radiation protection measures in the tests were substandard to best practices at the time.

In a report by the National Cancer Institute, released in 1997, it was determined that 90 atmospheric tests at the site deposited high levels of radioactive iodine-131 (5.5 exabecquerels) across much of the contiguous United States, especially in the years 1952, 1953, 1955, and 1957doses large enough, it claimed, to produce 10,000 to 75,000 cases of thyroid cancer. The Radiation Exposure Compensation Act of 1990 allowed for people living downwind of the site for at least two years in particular Nevada, Arizona, or Utah counties, between January 21, 1951, and October 31, 1958, or June 30 and July 31, 1962, and suffering from certain cancers or other serious illnesses deemed to have been caused by fallout exposure to receive compensation of $50,000. By 2014, over 28,000 downwinder claims for a total compensation of $1.9 billion had been processed. Additionally, the Energy Employees Occupational Illness Compensation Program Act of 2000 provides compensation and medical benefits for nuclear weapons workers who may have developed certain work-related illnesses.

Uranium miners, mill workers, and ore transporters are also eligible for $100,000 compassionate payment under the Radiation Exposure Compensation Program, while $75,000 is the fixed payment amount for workers who were participants in the above-ground nuclear weapons tests.

Nuclear test series carried out at the site

Operation Ranger – 1951
Operation Buster–Jangle – 1951
Operation Tumbler–Snapper – 1952
Operation Upshot–Knothole – 1953
Operation Teapot – 1955
Project 56 – 1955
Operation Plumbbob – 1957
Project 57, Project 58/58A – 1957–1958
Operation Hardtack II – 1958
Operation Nougat – 1961–1962
Operation Plowshare – 1961–1973 (sporadic, at least one test a year)
Operation Sunbeam (aka Dominic II) – 1962
Operation Storax – 1963
Operation Niblick – 1963–1964
Operation Whetstone – 1964–1965
Operation Flintlock – 1965–1966
Operation Latchkey – 1966–1967
Operation Crosstie – 1967–1968
Operation Bowline – 1968–1969
Operation Mandrel – 1969–1970
Operation Emery – 1970
Operation Grommet – 1971–1972
Operation Toggle – 1972–1973
Operation Arbor – 1973–1974
Operation Bedrock – 1974–1975
Operation Anvil – 1975–1976
Operation Fulcrum – 1976–1977
Operation Cresset – 1977–1978
Operation Quicksilver – 1978–1979
Operation Tinderbox – 1979–1980
Operation Guardian – 1980–1981
Operation Praetorian – 1981–1982
Operation Phalanx – 1982–1983
Operation Fusileer – 1983–1984
Operation Grenadier – 1984–1985
Operation Charioteer – 1985–1986
Operation Musketeer – 1986–1987
Operation Touchstone – 1987–1988
Operation Cornerstone – 1988–1989
Operation Aqueduct – 1989–1990
Operation Sculpin – 1990–1991
Operation Julin – 1991–1992

Areas

thumb|Nuclear explosions in various areas of the site

The site is broken down into areas. Some of the areas and their uses include the following:

Area 1

thumb|Tunnel in the U1a Complex within Area 1

Area 1 held eight nuclear tests for a total of nine detonations.

Area 2

Area 2 was the site of 144 tests comprising 169 detonations. Divider was a safety experiment test shot that was detonated at the bottom of a shaft sunk into Area 3.

In 1995 and 1997, plutonium-contaminated soil from "Double Tracks" and "Clean Slate 1" of Operation Roller Coaster (1963) was picked up from the Tonopah Test Range and brought to the Area 3 Radioactive Waste Management Site as a first step in eventually returning Tonopah Test Range to an environmentally neutral state. Corrective action regarding the contaminated material from the "Clean Slate 2" and "Clean Slate 3" tests has yet to be agreed upon.

Area 4

thumb|right|Big Explosives Experimental Facility (BEEF) in Area 4

Area 4 held 40 nuclear tests for a total of 44 detonations.

Area 5

Area 5 held 19 nuclear tests.

Milk Shakes radioactive release was not detected outside of the site's boundaries.

Area 6

thumb|Device Assembly Facility in Area 6

thumb|Control Point in Area 6

Area 6 held four nuclear tests for a total of six detonations.

The Device Assembly Facility (DAF)

Area 7

Area 7 held 92 nuclear tests.

Area 8

thumb|upright|Radioactive materials were accidentally released from the 1970 Baneberry shot in Area 8.

Area 8 held 13 nuclear tests for a total of 15 detonations. A plume of fire and dust was released, raining fallout on workers in different locations within the site. The radioactive plume released of radioactive material, including of Iodine<sup>131</sup>.

Area 9

Area 9 held 115 nuclear tests for a total of 133 detonations. The test also demonstrated the ability of a fighter aircraft to deliver a nuclear-tipped rocket and avoid being destroyed in the process. A Northrop F-89J fired the rocket.

The "Sedan" test of Operation Storax on July 6, 1962, a shot for the Operation Plowshare which sought to discover whether nuclear weapons could be used for peaceful means in creating lakes, bays or canals. The explosion displaced 12 million tons of earth, creating the Sedan crater which is 1,280 feet (390 m) wide and 320 feet (100 m) deep.

Area 11

Area 11 held 9 nuclear tests. Project 57's weapons safety test was conducted here on April 24, 1957, spreading particles emitting alpha radiation over a large area.

Area 14

Area 14 occupies approximately in the central portion of the NNSS. Various outdoor experiments are conducted in this area. No atmospheric or underground nuclear tests were conducted in Area 14.

Area 22

No nuclear tests took place in Area 22.

In 1983 the Department of Defense, the Department of Energy, and the Federal Emergency Management Agency performed the NUWAX-83 tests near Port Gaston in Area 26, simulating the explosion of a nuclear-armed helicopter and the resulting spread of nuclear debris over 65 acres. The radioactive material used to simulate the accident became inert in less than six months.

An eight-square-mile complex was constructed in Area 26 in support of Project Pluto. Those buildings have been used recently as mock reactor facilities in the training of first responders.

Area 27

Area 28

Area 28 no longer exists; it was absorbed into Areas 25 and 27.