(TNND) — New analysis of satellite imagery shows a clear increase in construction activity at Iran’s Pickaxe Mountain, a potential nuclear facility.
Iran appears to be hardening the already-fortified site, underscoring potential limits of American airpower alone to stop the country’s nuclear threat.
A new report from the Center for Strategic and International Studies shows a surge in construction activity this year at Pickaxe, an underground tunnel complex near Iran’s Natanz uranium enrichment facility and about 140 miles south of its capital city of Tehran.
Joseph Rodgers, deputy director and fellow with the Project on Nuclear Issues at CSIS, said the increased Pickaxe activity actually started around last September and corresponded with Iran building a security perimeter around the facility.
The uptick also matched when Mossad, Israel’s intelligence service, said Iran might’ve moved uranium centrifuges into the facility. But Rodgers said CSIS’ analysis couldn’t verify that claim.
Rodgers said Iran could be building a centrifuge assembly facility at Pickaxe.
It could be expanding activities there with plans to potentially enrich uranium there at some point down the road, he said.
But Rodgers doesn’t believe Iran is currently enriching uranium there, given all the construction activity underway that would make it difficult for scientists to work.
Rodgers said CSIS’ analysis is based on two different types of satellite imagery: both standard optical and synthetic aperture radar.
They pulled from more than six years of synthetic aperture radar imagery, which is a good way to track how surface hardness changes over time.
The roads going into and out of Pickaxe have seen “a significant increase” in hardness this year, Rodgers said. That indicates a surge of vehicle traffic packing down the roads.
What, exactly, Iran is doing in the Pickaxe tunnel system is less clear. As useful as synthetic aperture radar is at detecting surface hardness, it can’t penetrate deep into the ground.
“However, we are able to see with the optical images that the portal entrances to the facilities – so, the big tunnel sort of portals – are being hardened,” Rodgers said.
He said optical satellite images show Iran fortifying the tunnel entrances with concrete and dirt, potentially making it harder for the U.S. to disable the site with cruise missiles.
The U.S. didn’t touch Pickaxe last year when it bombed Iran’s nuclear facilities at Fordo, Natanz and Isfahan during “Operation Midnight Hammer,” part of Israel’s 12-day war against Iran.
Most construction started at Pickaxe around 2020, though some dates back to 2007. Still, Rodgers said Iran was still in the excavation phase of Pickaxe as of “Operation Midnight Hammer,” potentially making it a lower-priority target than Iranian facilities that were actively working on enriching uranium.
But knocking out Pickaxe would be no easy task for the U.S., Rodgers said.
Even the bunker-buster bombs dropped by B-2 stealth bombers would likely only disable the facility, not destroy it, he said.
Rodgers said Fordo was the hardest target hit by the U.S. in last year’s operation. He said Pickaxe is estimated to be 80 to 100 meters deep into a granite mountain, or about 20 meters deeper in the mountain than Fordo.
He also said the U.S. was able to blow up Fordo because we hit a structural weak point with ventilation shafts – a mistake he doubts Iran repeated at Pickaxe.
Also last year, the U.S. struck the above-ground nuclear complex at Isfahan. But Rodgers said there is also believed to be a uranium enrichment site in some nearby tunnels there.
The underground facilities at both Isfahan and Pickaxe are heavily fortified, but Rodgers said those are unlikely to be Iran’s only underground nuclear facilities.
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He also said Iran has “massive” stockpiles of uranium at various levels of enrichment, including what is believed to be around 440 kilograms of 60% enriched uranium.
Rodgers said Iran could make a “really rudimentary” nuclear weapon relatively fast, meaning in a matter of months, with the enriched uranium it already possesses. But he said Iran is seemingly years away from building a sophisticated nuclear weapon that could serve as an effective deterrent. Such weapons require 90% enriched uranium.
He said the American and Israeli militaries have set back Iran’s progress “considerably” over the last year.
But he said it’s time for diplomacy.
“We’ve pretty much reached the limit of what we can do with an air campaign,” Rodgers said.
The U.S. would likely need to send in ground troops to destroy Pickaxe, something Rodgers said would be ill-advised given the high cost in “treasure and probably blood” such an operation would take.
Diplomacy that includes verifiable limits on Iran’s nuclear program is the long-term solution, he said.
Negotiations have stalled. Iran is playing hardball. And the Trump administration hasn’t been very patient with negotiations, Rodgers said.
But he remains hopeful there’s still a path for talks.
“That’s, I think, the only way this can end without the U.S. just completely walking away,” he said. “And if we don’t get a diplomatic solution, then Iran’s probably almost certainly going to go down the nuclear weapons path again.”
Rodgers said the Obama-era Iran nuclear deal, the Joint Comprehensive Plan of Action, took 18 months of intensive negotiations.
“And that was 18 months of intensive negotiations when we knew exactly what we were negotiating,” Rodgers said. “The reason that I’m pretty critical of the recent MOU, which gave 60 days for negotiations for the nuclear program, is that we don’t really even know what we’re negotiating.”
The U.S. lacks a clear understanding of what capabilities remain at Iran’s previously targeted nuclear sites, Rodgers said.
He said the U.S. lacks a baseline understanding of Iran’s current nuclear capacity required for very technical negotiations.
And Rodgers said a new deal could take at least as long as the 18 months it took to reach the JCPOA.
“And I think any future deal with Iran needs to have the ability to go to these undeclared facilities on short notice and go inspect them, because there are many underground facilities in Iran,” Rodgers said. “We know about Isfahan and Pickaxe, and we’re highly suspicious of them in the open source. But there could be other places that we don’t know about.”