The mystique dates back to the Manhattan Project when physicists, engineers and military leaders worked to develop an atomic bomb in what was then known as the secret city on the hill.

Last week, the agency in charge of the country’s nuclear weapons pulled back the veil a bit and took reporters through part of the lab’s plutonium facility to offer an inside peek at where the bowling-ball-sized warhead triggers, known as pits, will be produced to help modernize the arsenal.

With questions arising recently on whether the lab can meet the National Nuclear Security Administration’s goal of making 30 plutonium pits per year by the end of 2026, one objective of the tour was to show the work areas where the essential tasks are done, partly to convey how they are being upgraded to meet future demands.

Officials giving the tour said the lab is making progress in its pursuit of pit production: Equipment is being replaced, workers are being hired and trained, and the facility is gradually being overhauled.

Anti-nuclear activists and other critics would like the lab’s entire weapons program, including the pit mission, to go away, saying it makes Los Alamos and the world less safe.

They oppose Northern New Mexico playing such a prominent role in U.S. nuclear posturing on the global stage and question whether a 45-year-old facility is being force-fit as a pit plant out of default; it is now the only place in the country where pits can be made.

But officials at the Energy Department and the lab have made clear whether people view pit production as an economic boon for the region or decry it as a costly venture that will feed a new arms race, it will be pursued until it materializes.

A key to the endeavor is cultivating a sufficient workforce. Officials giving the tour last week emphasized the need to not only bring in more workers but to keep them healthy and safe in a potentially hazardous environment.

And they championed the facility, saying it is well up to the task.

Although the facility came on line in the late 1970s, it was built sturdily and will process plutonium for many years after it’s modernized, said Ted Wyka, who manages the National Nuclear Security Administration’s local field office.

“It’s a good facility, a solid facility,” Wyka said.

Glove boxes a key component

As you prepare to enter the facility, you step into an antechamber. The two air-locked metal doors cannot be opened at the same time or an alarm goes off.

Air monitors are set up throughout the building as well as the surrounding area outside. Even a minute level of contaminants will trigger an alarm.

Bob Webster, deputy laboratory director for weapons, described the facility as “one giant lung” in which air continually flows through HEPA filters and then circulates back through the rooms.

On this day, the facility’s normally busy work stations and corridors are mostly empty because teams are doing inventory of various materials.

A big challenge is modernizing this facility — everything from upgrading fire and electrical systems to revamping entire sections — all while running daily operations, said Matt Johnson, division leader for pit technologies.

A feasibility study was conducted a decade ago to determine whether the facility could be retrofitted and, if so, what must be done, Johnson said. The study concluded it could, but it would require much work, including upgrades to meet seismic codes, he said.

A basic challenge is making all the fundamental changes, such as creating production lines, without adding any floor space, he said.

Glove boxes are a vital component in doing plutonium work, he said, referring to the sealed, treated-glass compartments with attached gloves that enable employees to work with radioactive materials.

It’s important to replace the old glove boxes with new ones as the lab pursues pit manufacturing, Johnson said, stepping into a work room with several of the compartments.

He stopped in front of an older model, bent over and placed his hand on a metal, bracket-like leg, saying this doesn’t comply with seismic codes. He pointed to a new glove box with metal braces underneath that meet the codes.

The new glove boxes also have modern instruments and gauges, though the basic function is the same.

Johnson said he and other managers would like to replace the glove boxes faster, but the manufacturer is backed up with two years’ worth of orders.

Webster said breached glove boxes tend to draw a lot of attention from media and safety inspectors because they release radioactive contaminants.

Torn gloves are generally the source of the breach, Webster said, noting there has yet to be a fail-safe glove invented that doesn’t tear. So all the lab can do is strengthen safety measures and protocols, he said.

Standard workwear consists of anti-contamination coveralls, booties, protective gloves taped to the arms and two radiation detectors — one for the wrist, one worn on the body.

Whenever workers pull their hands from a glove box, they compare the readings on the two devices to ensure one of them isn’t higher, which would indicate a possible breach.

The gloves vary in thickness depending on how radioactive the material is. The shielded gloves are especially difficult to use, whether it’s grasping a manual tool or handling a part, so workers must take regular breaks to avoid ergonomic stresses, Johnson said.

Although new computerized equipment is being installed, Johnson said he prefers to stick with the basics when it comes to the small trolleys that carry radioactive materials to various glove boxes and work areas.

These trolleys, which can be seen inside the glass, are linked to a thin rope and move along two tracks. People ask why he doesn’t use robots to transport the materials, and his answer is they would be much more expensive to maintain and repair.

Sometimes low-tech is better, he added.

If a radioactive release is detected, either by the workers’ devices or air monitors, an alarm sounds and the crew evacuates. The room is red-lit to signal it could be hazardous, and a radiological team is sent in to survey it.

Workers who were potentially exposed are tested.

The Defense Nuclear Facilities Safety Board, a government watchdog with residential inspectors, almost always writes up a breach in its weekly report.

The most serious risk is when a worker breathes in airborne contaminants, though this seldom happens, Webster said.

During a normal shift, whenever workers leave a secure room, they must be scanned for radioactivity, including the bottoms of their feet. All the safeguards have kept such contaminants from being tracked out of the complex, Webster said.

“It doesn’t happen,” he said.

Challenges ahead

The most pits the lab ever produced were 11 per year for Navy missiles more than a decade ago. The current plan calls for making almost triple that but with one significant difference: These pits will be forged from recycled plutonium rather than new material.

Pits are removed from weapons at the Pantex Plant in Amarillo, Texas, and shipped to the lab’s plutonium facility, where they are disassembled and the impurities are purged through pyrochemistry.

The plutonium is melted and cast into molds to create parts. Samples are tested. If they have the right chemical and isotopic properties, the parts are machined and welded together to make a pit.

A handful of prototypical pits are fashioned every year to refine the operation as the lab gears up to make war reserve pits. The first one is scheduled to roll out in 2024 [2025, I think now -- it's a matter of definition], with the aim of ramping up to full production two years after that.

Plans call for Savannah River Site in South Carolina to manufacture an additional 50 pits yearly by the mid-2030s. Even if the lab and Savannah River succeed in making a combined 80 pits, that’s just a fraction of the 1,000 pits a year produced at the Rocky Flats Plant in Colorado before it was shut down in 1989.

Lab and nuclear security officials have emphasized the pits’ purpose is to sustain, not expand, the arsenal. However, the pits will be fitted into two new warheads being developed.

The new W87-1 warhead will be key in replacing the outdated Minuteman class of missile with a next-generation intercontinental ballistic missile called the Sentinel. The pits also will equip the new W93 warhead, designed by the lab to be launched from submarines.

The president, the Pentagon and some political leaders contend modernizing the stockpile is necessary to deter Russia, China, Iran and rogue nations from acting rashly with nuclear weapons.

A formidable task is to expand capacity, officials told reporters during the tour.

Part of that is improving the equipment, Johnson said. He pointed to a new glove box that appeared to have multiple functions, but he didn’t discuss all of what it could do, only that it would help get pit production to 30 a year.

Boosting the workforce is the other part of the equation and, in some ways, the more challenging piece.

Initial training can last up to nine months, and it can take a person two to three years to develop the necessary skill set to work in the plutonium section, Johnson said.

There are also many daily hassles the workers must deal with, such as radioactivity checks when leaving work areas or the facility, even for lunch. For this reason, the lab offers hiring bonuses as incentives.

Critics of the lab’s nuclear program say the number of mishaps have increased as the facility becomes more crowded with personnel and the pace of work accelerates in the effort to meet the 2026 pit production goal.

Webster acknowledged missteps occur but said they always lead to a hard analysis of what wrong and how to avoid them in the future.

The facility has never had an accident that caused a nuclear chain reaction known as criticality, he said. If there’s the slightest hint of a neutron burst, workers are trained to move back far enough to be out of range of it, he said.

So far, the workers’ responses have been purely precautionary, he said.