Trillion dollar modernizing of America's nuclear arsenal underway

With undisguised pride, Los Alamos, N.M., the birthplace of the atomic bomb, announced on Oct. 2 the arrival of a new member to its nuclear family: a 7-pound sphere of plutonium designed to trigger a warhead with the power to level Manhattan.

Marked with a diamond-shaped stamp signifying its status as a "war reserve" weapon, the hollow ball — pewter in color, warm to the touch, the size of a grapefruit — is called a "pit," as in peach pit. It was made to fit into a new warhead, the W87-1, which will sit atop a new intercontinental missile, the Sentinel, that is being built to replace Minuteman missiles in 400 silos in Colorado, Wyoming, Nebraska, Montana and North Dakota. Each Sentinel can carry two warheads.

The new weapon joins an international arms competition that has never been more dangerous with what U.S. officials call two "peer" nuclear powers — Russia and China — nuclear saber-rattling from North Korea and Russia, and fear that Iran wants to join the nine-nation nuclear club that possesses 12,100 warheads.

The new pit is the first physical piece of a 30-year, $1.7 trillion nuclear "modernization" project by the United States to create new weapons and the missiles, planes and submarines to deliver them. As important as this first piece, though, is the process of producing hundreds like it, a process that stopped when the Rocky Flats Nuclear Weapons Plant outside Denver was closed in 1989. With the end of the Cold War, the Nuclear Security Enterprise (NSE), the complex of laboratories and factories that produce nuclear weapons, "atrophied," according to the pit announcement.

The W87-1 warhead "is reinvigorating and transforming the production complex such that NSE can once again produce all of the components typically required for modern nuclear warheads," according to Lawrence Livermore National Laboratory, which designed it. "This work will give the nation expanded options for maintaining an effective nuclear deterrence posture for decades to come."

Los Alamos created the first plutonium sphere — weighing 13 pounds — and exploded it in New Mexico in a test called Trinity on July 16, 1945. The sphere was surrounded by explosives that squeezed the ball into a critical mass, creating a fission atomic bomb with the heat and radiation present in the sun. A copy was dropped on and destroyed Nagasaki, Japan, 24 days later with the force of 20 kilotons. The size of the new W87-1 warhead is classified, but is thought to be between 300 and 400 kilotons.

After World War II, the lab made 150 pits for test explosions and a new weapon — the "Super," a thermonuclear or "H' bomb — which used a plutonium pit to trigger fusion of hydrogen gas and was first exploded in 1952. It was the beginning of a stockpile of nuclear weapons. During the Cold War, Los Alamos designed 94 different nuclear weapons, many of them using plutonium triggers.

Making a plutonium pit is a dangerous, difficult task done by skilled machinists whose hands are thrust inside sealed glove boxes to prevent the escape of highly radioactive plutonium. After Rocky Flats opened in 1952, several pits were made each day, 1,000 a year, in an eight-week process starting with a "button" of plutonium metal created in nuclear reactors in Hanford, Wash. Resembling a round, squat biscuit, the buttons were heated, rolled, lathed, and trimmed into two half-hemispheres. As much as a third of the original button was discarded as waste.

Pits had to meet exacting physical and chemical parameters to ensure that they would fission and explode as designed. Between 1952 and 1989, Rocky Flats produced tens of thousands of pits. Those that met the parameters were stamped with a diamond-shaped mark in indelible ink and inserted into warheads or stored in Pantex, Texas, where warheads were assembled for delivery to the military.

Soon after Rocky Flats was invaded in 1989 and closed by the FBI for environmental and safety crimes, physicists at the Lawrence Livermore National Laboratory in California developed the idea of recycling old pits, which are subject to radioactive decay. By then, Hanford had produced more than 60 tons of plutonium and had also closed.

Large-scale pit production ceased in 1989 with the shutdown of the Rocky Flats plant. According to Los Alamos spokesman Steven Horak, Los Alamos "performed limited pit production at war reserve quality for research purposes only from 2007 to 2011 in support of the W88 warhead." The W88 was made for the Trident II submarine-launched ballistic missile.

In 2013, the Los Alamos pit facility, called PF-4, was closed for three years because of mishandling of plutonium rods that could have created a criticality accident, according to Dylan Spaulding, a senior physicist with the Union of Concerned Scientists.

In 2014, the Nuclear Weapons Council, which oversees nuclear weapons, told Congress that the military needed "at least" 80 new pits a year. A year later, Congress mandated that production, set a deadline for 10 pits this year and 30 by by 2030 at Los Alamos. Another 50 are to be produced at a new facility at the Savannah River National Laboratory in South Carolina.

Those deadlines created a crash construction program at PF-4, with workers tearing out old contaminated glove boxes at night and wrapping the area in plastic before a new shift of workers arrived to install new glove boxes for work on the new pits.

"The best analogy I can come up with is that we are overhauling and upgrading a plane during flight with a load of passengers on board," said Mark Davis, LANL's associate lab director for weapons production.

By this time, Los Alamos had lost many of its experienced employees with the expertise to make pits. Luckily, hundreds of boxes of documents — notebooks, welding procedures, technical illustrations — rescued from Rocky Flats, were found stored in a vault at the Denver Federal Center. "It's like the last scene of 'Raiders of the Lost Ark,'" said Joe Watts, a LANL project manager.

The documents proved invaluable: "Standing up pit production at Los Alamos from the Rocky Flats archive is like being asked to recreate the Sistine Chapel from Da Vinci's drawings," says Bob Putnam, former program director for pit manufacturing at Los Alamos.

As lab managers unsealed and combed through the boxes, Los Alamos "became like monasteries in the Dark Ages that preserved the knowledge" to produce plutonium pits, said Robert Webster, deputy director of weapons at Los Alamos.

Today at PF-4, old plutonium pits from Pantex are subjected to pyro-chemistry and purified. The metal is then heated into a hot syrup and poured into molds, creating two halves of a sphere. These are welded together. This process is done in rows of connected glove boxes, the plutonium moving from one to another in an overhead trolley system and dumbwaiters that raise and lower it. Training takes years. Failures have been frequent.

Experts across the Nuclear Security Enterprise worked for eight years to "develop and mature qualification, certification, and product acceptance processes required to manufacture" the first new pit, the government reported. "Achieving First Production Unit of the W87-1 pit is an important milestone for the United States' nuclear weapon stockpile modernization."

"The reestablishment of pit production capabilities is the largest and most complex infrastructure undertaking at NNSA since shortly after the Manhattan Project," Jill Hruby, administrator of the National Nuclear Security Administration, told the Strategic Weapons In The 21st Century Symposium on April 18. "Our current total estimated acquisition cost range for pit production is $28 billion-$37 billion. ... I know that's a lot of money. ... We anticipate Los Alamos achieving the capability to produce the 30 pits per year envisioned by the two-site plan in or near 2028, with increased manufacturing rate confidence as we install equipment through 2030."

The momentum begun at Los Alamos will continue despite a federal court decision on Sept. 30 that the government's plan for two pit-manufacturing sites violates the National Environmental Policy Act. U.S District Court Judge Mary Geiger Lewis in South Carolina found that the plan's purpose had changed from the original justifying analysis, which did not consider pit production at two sites.

The court allowed work to continue at Los Alamos while the government and five watchdog groups who brought the lawsuit negotiate. The groups contend that the court's decision will require the government to make a "thorough analysis of the impacts of pit production at DOE sites throughout the United States, including radioactive waste generation and disposal."