(U.S. National Archives)
Wearing
protective goggles, observers from Canada and Britain watch MET
(Operation Teapot), a 22-kiloton nuclear detonation above Frenchman Flat
at the Nevada Test Site, on April 15, 1955.
The time: 1955. The place: a dry lakebed in southern Nevada called Frenchman Flat. An explosion equivalent to 22,000 tons of TNT creates a roiling mass of superheated, low-density gas. This fireball rises and collides with the surrounding air, creating turbulent vortices that suck smoke and debris up fro
m the ground into a column. The “stem” rises into cooler, thinner air, where the ascent slows, debris disperses, and moisture condenses to form a “cap.” Over days and even months, nuclear fallout spreads and drifts to Earth.
Between 1951 and 1962, well after the detonations at Hiroshima and Nagasaki, 14 mushroom clouds rose above this corner of the Nevada desert. They were part of a long, complex, and varied program of nuclear testing, and each had a broad audience. One part was global, as the Cold War superpowers, the United States and the Soviet Union, squared off; the other was sitting on benches on an overlook seven miles away. A stream of political and military VIPs sat there, squinting at blasts and being buffeted by powerful shockwaves. Today, 11 rows of the benches sit under the desert sun, with nails jutting from their warped, desiccated planks. “I like these benches,” says Colleen Beck, an archaeologist with the Desert Research Institute (DRI), part of the Nevada System of Higher Education. “While hardly anyone comes here now, you can really imagine people sitting on them, watching a test.”
(Courtesy
Colleen Beck, Desert Research Institute, and National Nuclear Security
Administration/Nevada Site Office, U.S. Department of Energy)
Benches used to watch explosions still stand several miles from the detonation site.
(Wikimedia Commons, Photo: Doc Searls)
In August 1945, the United States dropped nuclear devices over Hiroshima and Nagasaki, hastening the Japanese surrender that ended World War II. The blasts, very small by the standard of what would come, killed more than 100,000, injured and sickened countless more, and left two cities in ruin. Two months later, President Harry Truman told Congress that the atomic bomb signaled “a new era in the history of civilization.” He went on: “Atomic force in ignorant or evil hands could inflict untold disaster upon the nation and the world. Society cannot hope even to protect itself—much less to realize the benefits of the discovery—unless prompt action is taken to guard against the hazards of misuse.”
Congress reacted in 1946 by creating the Atomic Energy Commission (AEC) to oversee nuclear development. Responding to the threat of a Soviet nuclear program, the AEC authorized nuclear weapons tests in the South Pacific, and then later decided the Nevada desert would be less vulnerable to attack. In December 1950, the commission recommended establishing a permanent proving ground on a piece of the old Las Vegas Bombing and Gunnery Range. Truman concurred, and the first atmospheric detonation at the Nevada Test Site, a one-kiloton bomb dropped on Frenchman Flat, took place a month later. The U.S. nuclear testing program continued for 41 years and included 928 nuclear tests (with 1,021 total detonations). Most were underground, but 100 tests were atmospheric, or out in the open. Today, as the Nevada National Security Site, it is still used for radioactive waste storage, first-responder training, “subcritical” nuclear tests, and other projects.
The nuclear explosions at the Nevada Test Site were largely clustered in four areas: Yucca Flat, Pahute and Rainier Mesas, and Frenchman Flat, which stands out for its concentration of aboveground remains. “As time passes, memories are fading about what nuclear weapons can do,” says Beck. “But when you go out there on Frenchman Flat, you can really see how powerful a nuclear detonation can be.”
(National Nuclear Security Administration/Nevada Site Office, U.S. Department of Energy)
Fizeau (Operation Plumbbob), 1957
Beck was born a month after the Test Site opened 63 years ago. She conducted fieldwork in Peru and the American West before moving to Las Vegas in 1989. She joined the DRI the next year. “When I began, we were really only looking at prehistoric archaeology and at mining- and ranching-related facilities,” she says. Underground testing was still taking place when she started her work there, and part of her job was to identify Native American artifacts in areas scheduled for detonations.
It can be hard to imagine anyone actually living there, Beck says, in part because of lingering radioactivity and ongoing nuclear waste research, but evidence is all around. The variety of stone points found on-site shows occupation that goes back through the Paleoindian period to some 11,000 years ago. At a site called Midway Valley, DRI researchers found a quarry for chalcedony and obsidian that was used for thousands of years. And in Fortymile Canyon there are petroglyphs that some interpret as evidence of vision quests.
There are also later habitation sites for Native Americans, as well as for the prospectors, miners, and ranchers who arrived in the mid-nineteenth century. Often clustered around springs, such sites include seasonal camps, rock shelters, cabins, horse corrals, and water troughs, as well as mining equipment and the writer’s cabin of B.M. Bower, who wrote dozens of novels set in the American West.
“But one of the biggest thrills,” she recalls, “was to go into Frenchman Flat and look at the atmospheric-testing grounds. Within a year, it had become apparent to me that the remains at the site were significant historically but were being totally ignored.”
(Courtesy
Colleen Beck, Desert Research Institute, and National Nuclear Security
Administration/Nevada Site Office, U.S. Department of Energy)
Standing
remains at Frenchman Flat include a vault (top), train trestle
(middle), and an aluminum cylinder for a pig experiment (bottom).
At Frenchman Flat, Beck leads a visiting reporter through some of the remains, which are concentrated in about 4.5 square miles of dusty terrain. There, nuclear weapons were dropped by bombers, carried aloft by balloons, perched on towers, and fired from a cannon. Each nuclear detonation was part of a test series or “operation,” often consisting of dozens of “shots,” or explosions. Countless experiments and measurements were conducted and recorded, sometimes across multiple shots or operations.
For example, for one shot called Priscilla, a 37-kiloton weapon was detonated from a balloon 690 feet off the ground on June 24, 1954, as part of Operation Plumbbob. A structure that looks suspiciously like a bank vault remains on Frenchman Flat from that test. “Look how thick those walls were,” Beck says, approaching the twisted steel rods—once encased in concrete—radiating from its sides. The interior of the vault, however, survived intact. “Everyone jokes that they were trying to make sure the money would be safe after a nuclear blast,” Beck says. In fact, according to a 1957 government document, the vault was donated by the Mosler Safe Company “out of the concern on the part of banks and insurance companies over protection of records and valuables.”
Surrounding the vault in every direction are other battered and rusting ruins. A twisted train trestle sits atop two concrete blocks—what’s left of a railway bridge that endured two explosions. An airplane hangar has collapsed beyond recognition. An underground parking garage, included in tests to see how such buildings would perform as bomb shelters, is mostly intact. There is also a group of domed shelters made from concrete and rebar. Some are blown apart, others are not. “They were trying to see whether a dome shape would have a better survival rate than, say, a rectangular building” Beck says. Another feature on Frenchman Flat is an aluminum cylinder with two square holes cut into its side, lying horizontally and held upright by three steel plates. In Priscilla and other tests, pigs were used as human proxies. During the years of atmospheric testing, 1,200 pigs lived on the site in pens nicknamed the “Pork Sheraton.” Prior to detonations, some were placed in containers such as this and outfitted in a variety of fabrics to test how materials held up under intense heat.
(National Nuclear Security Administration/Nevada Site Office, U.S. Department of Energy)
Priscilla (Operation Plumbbob), 1957
After testing was conducted, many such atmospheric detonation sites were cleaned up, but Smoky was not. “This is the best intact atmospheric nuclear test site,” Beck says. “It makes it extremely special.” She and her team, wearing protective suits, recently conducted an archaeological assessment there. Primary among the remains are twisted fragments and stanchions from the 700-foot tower that held the Smoky device. Evidence of experiments remains, too: A few hundred scattered lead bricks had shielded some kind of instrumentation, and there are French- and German-designed personnel bunkers that were being tested. There is also a hill next to ground zero that is called the “Coke Hill” but is covered in charcoal, and another smaller hill behind it. As with a number of the structures the DRI has documented, no one knew what the hills were used for until engineering drawings finally turned up—they were earthen berms used to protect instrumentation. Despite extensive written documentation, there is much that is still unknown about some sites. “We believe in most cases the data exists somewhere,” Beck says.
(Courtesy
Colleen Beck, Desert Research Institute, and National Nuclear Security
Administration/Nevada Site Office, U.S. Department of Energy)
Tower stanchions, Yucca Flat
Of more than 300 million U.S. residents, some 80 million were born after the 1992 testing moratorium. And less than a third of the population is old enough to remember the mushroom clouds of atmospheric tests that rose over the Nevada desert. “I’m not sure how any people, even my kids, can grasp what it was really like,” Beck says, thinking back to the time when nuclear anxiety permeated daily life. She sees her work as preserving at least a glimpse of that era.
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