SANTA FE, N.M. — About 300 feet directly below the McDonald’s parking lot in Los Alamos lies what was once one of the most secret and secure places in the world.
Known as the “Tunnel Vault” to the few who knew its purpose, a 230-foot long underground passage was first used to stockpile the United States’ supply of nuclear components after World War II.
“They needed a really secure facility for nuclear material that needed to be safely stored. There were alarms and armed guards stationed outside,” said Ellen McGehee, the historic facilities manager at Los Alamos National Laboratory. “It’s one of the coolest vintage Cold War facilities. It has the look and feel of a high security area.”
A guard tower – complete with gun ports and bulletproof glass – stands sentry behind a tall chain-link fence with barbed wire strung across the top. One must pass through a series of bank vault doors to get to the area where the weaponry was stored.
The tunnel remained a secret until last year, when it was declassified.
Kevin Roark, who has worked at LANL for more than 20 years and now serves as senior communications specialist, said it wasn’t until recently that he knew its true purpose.
He recalled inquiring about it one day soon after he started work there. A lab official checked his security clearance and finally told him, “You don’t need to know.”
Now, the lab is allowing the secret to get out, though access is still restricted. Lab officials conducted a media tour of the tunnel and other “behind the fence” facilities on Tuesday. A limited number of LANL employees and their family members will get to see it on Saturday during a celebration of the lab’s 70th anniversary. And, the lab recently posted a three-minute tour of the tunnel on its YouTube website.
National historic park proposal
McGehee, for one, would like to see the tunnel, built into an Omega Canyon wall in Technical Area 41, opened up to the public one day. Most recently, from 2004 to 2012, the tunnel was used as a classified museum that displayed legacy and modern systems of nuclear development.
“It would be nice to do something similar with this, with interpretive displays that talk about Cold War history,” she said. “People react well to being in a facility from that era. There’s an emotional component to it that’s better than just seeing pictures.”
Its vaulted doors may be open to that possibility. Legislation introduced in both the U.S. House and Senate this year proposes that a Manhattan Project National Historic Park be established at Los Alamos, as well as at other nuclear research and development facilities in Oak Ridge, Tenn., and Hanford, Wash.
Potential park properties include buildings in the Los Alamos Scientific Laboratory National Historic Landmark District in the city’s downtown and six other industrial sites located behind the lab’s fence. Those include the Pond Cabin and Slotin Building, where plutonium research was done; the Gun Site and the Quonset Hut, where the Little Boy and Fat Man bombs were assembled; and the V-site, where the bombs’ prototypes were put together.
Though the tunnel was built post-Manhattan Project in 1948-49 as part of rebuilding LANL for its new mission, McGehee said she could see how the tunnel could be utilized as part of the historic park in Los Alamos.
“It’s not part of the park proposal, but it’s part of the experience,” she said.
Its place in history
The tunnel vault was used to store nuclear weaponry for only about nine months.
“It was used to stockpile pits, cores and components until other Cold War infrastructure was developed,” McGehee explained. “Then it was used to store other weapons-grade material for development of the next phase of weapons.”
It was used in that way for decades until the facility was cleared out in 2001 after the Cerro Grande Fire.
On Tuesday, media members were led through two locked doors that opened up to a long hallway.
“They used to back paneled trucks from Albuquerque down here and loaded and unloaded the components that they needed,” McGehee said.
But the Tunnel Vault wasn’t used exclusively for weapon component storage. There’s a room off to the left of the hallway that was used as a separate laboratory for research projects and has a history of its own.
“It was called ‘the hull,’ ” McGehee said of the room. “In the 1950s it was used for physics experiments, and it’s where research was done on the neutrino, which won a Nobel Prize.”
At the time, the facility was operated by the Atomic Energy Commission.
“So when physicists wanted to do research, they actually had to write the AEC to get permission,” she said.
Beyond that is a larger room with a vault door in one corner. Through that door is an area where five other vault doors are located, each protecting separate storage areas where the nuclear stockpile and components were once stored.
“Record keeping was really important,” McGehee said. “Especially when the stockpile was really small, they wanted to make sure they knew where everything was.”
Time will tell if the once secret tunnel will ever be open to the public. McGehee said there is some opposition to the historic park proposal, as some people see it as glorifying the nuclear age.
“It’s controversial, but it’s a part of American history that shouldn’t be ignored,” she said.