For the past five years, crews have been taking apart the San Onofre nuclear plant piece by piece.
The plant, which goes by the official name of San Onofre Nuclear Generation Station (SONGS), was shut down in 2013.
The massive decommissioning started in 2020 with the demolition of auxiliary buildings. Most of the material has been transported via rail to Clive, Utah.
"We removed about 400,000 (pounds of rubble),” said Ron Pontes, general manager for site closure and environmental oversight at SONGS.
All that remains are the iconic domes, which have been a San Diego landmark since the early 1980s.
“You know where you are when you see these domes,” Pontes said. "The San Diego County line is just a little bit farther up the road here."
But the domes' days are numbered, too. Right now, crews are prepping for the demolition by removing the nuclear reactors inside the domes.
Once that's done, the domes will be demolished, but Pontes said there won’t be a dramatic implosion. Instead, crews will use excavators to slowly tear them down.
“Those large excavators will work around the outside of the building," he said. "They'll pound away at the building ... The weight of the building will actually fall down.”
Pontes said that’s safer than implosion because it reduces the risk of releasing nuclear radiation.
“Early in this business of demolishing these plants, there was some use of a of explosives to bring down buildings. And that generates a lot of dust,” he said.
The crews at SONGS took precautions to ensure dust from the demolition doesn’t pollute the air, Pontes said. There are several air quality monitors around the site, including two large tents where crews break down concrete chunks into rubble for transport.
“The tent ... is connected to the building, and it's also under negative pressure," Pontes said. "So as that rubble is removed from the inside of the building to the tent and handled to be placed inside gondola cars, it too is being controlled so that there's not an uncontrolled release of radioactivity at all.”
Once the domes are demolished, the only things that will remain are the protective sea wall, the switchyard and the dry storage where spent nuclear fuel is housed. The federal government has yet to approve a site for disposing of that.
“It's a national problem," Pontes said. "The U.S. government was supposed to start picking up the fuel from our commercial reactors in 1998. Now it's almost 2026.”
Pontes expects the domes to be fully demolished by the end of 2027 and the entire decommissioning to be complete by 2028.
