For 80 years, the Tennessee site has managed the nationʼs enriched uranium.
Names often herald origins or indicate purpose. That is not the case for Y-12, a national security site in the formerly remote Bear Creek Valley of east Tennessee. Because neither the letter nor number signifies anything, Manhattan Project officials—who stood up the facility in 1943 to convert naturally occurring uranium into enriched uranium for use in atomic weapons—thought no one would deduce what was happening at the site from the name alone. The enriched uranium produced at Y-12 was used in the Little Boy bomb dropped on Hiroshima on August 6, 1945. World War II ended shortly thereafter.
Eighty years later, Y-12 is still responsible for the production, storage, and handling of enriched uranium in the United States. Since 1953, Y-12’s mission has included the manufacturing and maintenance of secondary stages for nuclear weapons. A secondary stage contains enriched uranium and significantly increases the yield of a nuclear weapon.
“Anything to do with enriched uranium occurs here at Y-12,” says Gene Sievers, site manager for what’s known today as the Y-12 National Security Complex. “Our legacy is a source of pride for the workforce. We continue that work to this day, and the nation continues to look to Y-12 for answers to very complex problems.”
In 2007, the site was recognized by the National Nuclear Security Administration as the nation’s Uranium Center of Excellence.
ʻCollaboration is the wordʼ
Y-12 works closely with the rest of the nuclear security enterprise to ensure the safety, security, and effectiveness of America’s nuclear weapons. The design agencies—Los Alamos, Lawrence Livermore, and Sandia national laboratories—work with production agencies—Y-12, the Pantex Plant, and the Kansas City National Security Campus—to maintain and update weapons. “The enterprise has a large work scope; it’s too big for any one place to do,” Sievers explains. “Each lab, plant, and site has its own expertise, so we leverage one another to get the mission done. Collaboration is the word.”
The production agencies turn concepts from the design agencies into reality. At Y-12, production and technology realization teams are assigned to different weapon systems to facilitate the transition from design to manufacturing. “As anyone who has gone through an engineering class probably knows, you can design anything,” Sievers says, “but the real trick is designing something that can be built, and in this case, that can be built at rate production.”
At any given time, Y-12 is performing work on multiple weapons systems. This work could involve the production of nuclear components (such as secondary stages), surveillance testing to determine how certain weapons components are aging, and the dismantlement of retired weapons, which involves the removal of nuclear material.
Sievers, who served in the U.S. Navy on both nuclear-powered and nuclear-armed submarines before coming to work at Y-12, says his military background informs his commitment to Y-12’s—and the nuclear security enterprise’s—mission, which is to ensure that the missiles and bombs in America’s nuclear stockpile are reliable and can be used effectively by the United States military if and when necessary.
“Our airmen and sailors spend zero time worrying about what is on the tip of a missile because we have proven there is essentially zero defect,” he says. “I never want the sailor or the airman to doubt for a second what is on the end of that delivery platform.”
An evolving mission
As the nation’s Uranium Center of Excellence, Y-12’s mission extends beyond weapons in the active nuclear stockpile.
As part of its global security work, Y-12 offers training to nuclear industry workers, emergency responders, and security forces on how to safeguard and handle nuclear material.
Y-12 also provides the enriched uranium for the U.S. Navy’s nuclear-powered submarines and aircraft carriers. The uranium used in naval reactors comes from dismantled nuclear weapons and powers the vessels. To date, according to the Department of Energy (DOE), naval vessels have safely traveled approximately 200 million miles on nuclear power.
Y-12 also occasionally collaborates with Oak Ridge National Laboratory, which is located one ridge and several miles to the southwest. Sievers explains that “Oak Ridge is a DOE laboratory with a national science mission, and Y-12 is more focused on production.”
In addition to Y-12 supplying fuel for Oak Ridge’s high-flux isotope reactor, which creates medical-grade isotopes for cancer treatments, the two facilities also collaborate on computer modeling efforts.
“Oak Ridge has the high-speed computing capability over the hill there,” says Y-12 Chief Scientist Jenn Charlton. “We work with their modeling groups to help inform how we do our production sciences.” High-fidelity computer models allow Y-12 employees to better understand the materials they’re working with before starting any manufacturing.
Although much of Y-12’s machinery and processes have been updated over the years to match technological breakthroughs, the buildings that shelter them haven’t always received the same attention. In recent years, that has started to shift.
In 2010, operations began at the 100,000-square-foot Highly Enriched Uranium Materials Facility, which contains state-of-the-art equipment and infrastructure for the secure storage of highly enriched uranium. “We receive materials in this facility from all over the world as part of the global threat reduction initiative, as well as material from sister sites all over the country,” explains an operations manager in a 2010 video. “Weapons are brought in from other sites for storage here, many of these weapons are either disassembled or go through a quality evaluation process for future shipment back out into the stockpile.” The facility, which is made of concrete and steel, was built to withstand flooding, lightning strikes, seismic events, and tornadoes.
Another construction project—the Uranium Processing Facility, or UPF—is currently in the works. UPF will house many capabilities currently taking place in building 9212, where uranium is enriched using 1940s-era machinery from the Manhattan Project. UPF will allow for safer and more cost-efficient operations.
In late 2023, ground will be broken for Y-12’s new Lithium Processing Facility, which is expected to be completed in 2031 with operations fully commencing in 2034. Y-12 has been processing lithium, a soft, low-density metal that is a key component in secondary stages, for seven decades.
“There are two strategic materials we deal with, enriched uranium and enriched lithium,” Sievers says. “So, it makes all the sense in the world for the nation to invest in modern infrastructure for those two strategic materials and those are the first two major construction projects at Y-12.”
The workforce of the future
As infrastructure is being revamped, so is Y-12’s workforce of approximately 8,000 people.
“Work continues to increase, but we’re also finding that the workforce is turning over faster,” says Senior Director of Analytical Chemistry Amy Wilson. “In previous generations, a person might stay in one job for his or her entire career. That is not the current generation.”
The changing workforce, however challenging, also offers opportunities. In addition to growing an organization to capture the knowledge of people who are leaving, “we’re expanding our research and development group from 113 to nearly 200 researchers,” Charlton says. “It just creates a more energized research and development environment. A lot of energy has come from the new facilities we have coming online and our evolving mission space; it’s really exciting.” ★