5 key questions the Army is still working out for its nuclear microreactor plan

WASHINGTON — The US Army last week made it official: nuclear microreactors are coming to US bases, thanks to roughly $2.2 billion spread across five companies. 

The goal of the Janus program is to produce 20 prototypes that will be contractor owned and operated at five bases, with the first one up and running by fall of 2028. And the reason for this move, officials said, should be self-evident. 

“Unlike in prior conflicts, we now know that our domestic electric grid is potentially at risk in a conflict,” Jeff Waksman — the principal deputy assistant secretary of the Army for installations, energy and environment – told reporters during a call on Wednesday. “We also know that we will not necessarily be able to move fossil fuels easily wherever we need them to go.”

But while the reasoning may be clear, there are still a number of questions about how, exactly, this effort is going to play out. After all, nuclear physics aren’t famous for being simple, as Waksman himself noted.

“We know that this is going to be very difficult, and that there’s a very real chance that one or more of these [Janus program] companies will fail,” he said.

Here, then, are five key questions the Army knows it has to sort out going forward. 

Question 1: What is the Army’s plan for dealing with the microreactors’ nuclear waste and preventing contamination? 

While the Janus microreactors are in various stages of development, the operational core life expectancy could be as short as a handful of years, up towards a couple of decades. Additionally, some of the designs have the small, microreactors sitting above ground, while others require some digging into the earth’s surface.

The question becomes what will the Army and companies do with the nuclear waste, and how they will prevent possible ground contamination.

“We’re very sensitive to making sure that local soil is shielded properly,” Waksman said. “A part of the contract is that all radiological material has to be removed from the site within two years of [the end of] operation. So these reactors cannot leave radioactive soil behind.”

“This is actually one of the big differences with what we are doing versus the way that this was done in the 1950s and 1960s,” he added.

Waksman said the plan is to have “no long-term nuclear waste” at any of the installations hosting these microreactors, and emphasized that it is one of the program’s requirements. But he acknowledged that the service is still working through how it will handle the waste, including discussions with the Department of Energy.

“We don’t have that fully signed and agreed to yet, but the intent is to have a deal with the Department of Energy, where the waste will go to a DOE site of some sort, and there would be money transacted, and then DOE would take title to that waste,” Waksman said. “We are not going to stand up an Army-licensed nuclear waste facility. That would not be beneficial or practical.”

Question 2: Is there actually going to be enough fuel for these reactors? 

The companies selected for Janus are all using High-Assay Low-Enriched Uranium (HALEU) feedstock – uranium enriched to a concentration level between 5 percent but below 20 percent – to produce Tristructural Isotropic (TRISO) fuel particles for each reactor’s core. 

However, the US supply of HALEU is limited, and as of right now, there simply is not enough fuel supply available to feed the 20 microreactors planned for this program. 

“We expect sufficient prioritization to ensure that we have the uranium that we need for our fastest moving reactors…. [But] to provide the uranium, the HALEU, for more than 20 reactors, is probably going to push beyond what our supplies are as a nation,” Waksman explained.

“There are other people who need HALEU,” he added. “NASA has announced their SR-1 mission, and there are other things going on that need uranium, and so that is why you know the nation on a bipartisan basis has tried to stand up new enrichment capability.”

This is where the larger Trump administration push to increase nuclear power comes into play. DOE is currently working on ways to shore up its HALEU supply for both commercial and government uses, by downblending Highly Enriched Uranium (HEU). That push included DOE’s January announcement that it plans to spend $2.7 billion over 10 years to boost domestic enrichment services of both low-enriched uranium (LEU) and HALEU.

“This is really an all-of-government effort,” Waksman said. “We are tied in very closely with the folks at DOE and NNSA [National Nuclear Security Administration] trying to stand up new enrichment capability, and we will do what we can to deliver what we need through stockpile, and then to hopefully have fresh enrichment capable of delivering some of the HALEU for the later reactors in this program.”

Question 3: Can the Army, or the Pentagon writ large, actually afford to expand this program? 

The $2.2 billion invested in Janus is effectively to help get a set of prototypes up and running. The actual installation of microreactors on US bases will be even more costly, and expanding that across multiple bases — or eventually, abroad — will keep costs driving forward. 

Which is why, Waksman said, that while some companies are touting possible price points for their future microreactors, it simply isn’t clear if the contractor owned and operated model will bear out.

“We have some idea of where we think that these reactors can get to, but that is really what we’re trying to do here with Janus, which is to flesh out how we can get those prices down, and what can we get those prices to,” Waksman said.

“We don’t ever expect that microreactors are going to be quite as cheap as big reactors,” he added. “There are just engineering and physics reasons why, but the sort of applications for microreactors also lend themselves to being able to handle higher prices.”

In austere locations, Waksman estimated that the department is “regularly paying” 40 cents a kilowatt hour for natural gas, So the microreactors end up costing $1 kilowatt hour, “that’s not going to work.”

“I don’t want to give you a dollar number just because it would be a huge guesstimate, but certainly part of the selection process was us having confidence that these companies can get their prices down in the range that would be useful for the Army,” he added. 

Question 4: How will the Army keep these reactors safe?

It doesn’t take much imagination to realize that a nuclear reactor on a military base would make a fat, juicy target for any state or non-state actor. While a kinetic strike on the homeland seems unlikely, hacking a reactor through digital or physical means and causing a meltdown would be naturally tempting for adversaries.

Since HEU (a concentration above 20 percent) will not be used to fuel Janus microreactors, Waksman said the department does not need to put in place the same precautions as if they were a nuclear weapon or a naval reactor.

“However… one of the benefits of being on an Army installation is that we will be leveraging the Army security that already exists,” he explained. “So obviously, physical security is part of our requirements. We have… additional security requirements for important infrastructure on Army installations that go beyond what you will often see in the private sector.”

While Waksman did not detail what those additional security measures may be, the military is already concerned with a host of cyber and infrastructure threats, and uses air defense and counter drone systems to protect critical US infrastructure. The Trump administration is also laying the groundwork to stand up Golden Dome, a sprawling, multilayered homeland air defense system. 

Question 5: How will regulation of these reactors work? 

The microreactors destined for Army installations under Janus will be licensed by the service, not the Nuclear Regulatory Commission (NRC), according to Waksman. 

But given the goal is, in part, that the companies can use the Army development funding to help develop reactors for commercial use, the service is currently working with the NRC to devise a process to make the additional licensing process “as smooth as possible,” Waksman said. 

“There is no formal NRC process. However, the whole idea here is that at the back end of this, we want a commercial product,” he added. “We want [the companies] to be able to turn around and get these licensed by the NRC and sell to other commercial entities.”

“It does not mean that a DOE licensed reactor is automatically Army licensed, or that an Army licensed reactor is automatically NRC licensed. That’s not how the process works,”Waksman furthered. “But we want to make sure that there are no curveballs [and] a company designs something for the Army and then gets told something totally contradictory by the NRC about what makes software qualified or what makes a material qualified.”

When it comes to environmental laws like the Clean Air Act and the National Environmental Policy Act (NEPA), the service still needs to adhere to rules.

“Obviously there’s been a significant amount of NEPA reform, so NEPA will move faster than it traditionally did,” Waksman told reporters. “But all the environmental rules that would apply to nuclear reactors in the commercial sphere would also apply here.”