SF Gate Article, or read below. Heather’s last name has been updated.

Heather Hoff and Kristin Zaitz want to use motherhood and global warming to change the way Californians feel about nuclear power — before it’s too late.

Hoff and Zaitz both work at the state’s last nuclear power plant: Diablo Canyon, near San Luis Obispo. Both are convinced California can’t fight climate change without it. And both worry that the seaside plant, which is nearly surrounded by earthquake faults, could soon close, if environmentalists and some state officials get their way.

So Hoff and Zaitz have formed a new group, Mothers for Nuclear, to convince Californians that Diablo is both safe and necessary.

And some of their activism will be directed at their own employer: Pacific Gas and Electric Co.

The San Francisco utility, which owns Diablo, has not yet decided whether to try to renew the plant’s federal operating licenses, which expire in 2024 and 2025. Instead, PG&E has been telling Diablo’s 1,500 workers that any effort to renew the licenses would face major hurdles. Hoff and Zaitz want PG&E to commit to keeping the plant open, assuming state and federal officials allow it.

“We feel we can’t just do nothing,” said Zaitz, 35, whose job involves studying how well the plant and its equipment can withstand earthquakes. “In general right now, people at the plant are optimistic. But they’re starting to wonder which direction the company is going to go and which direction the state is going to guide them.”

Both women have worked at Diablo for more than 10 years, and each lives near the plant: Zaitz in Los Osos and Hoff in San Luis Obispo. Both are raising children there, a point they emphasize when talking with people about nuclear power.

Pressure governor

“If it’s coming from the utility, it’s not quite as credible as if it’s coming from two moms,” said Hoff, 36, a former operator in Diablo’s control room who now writes procedures for other operators.

In addition to PG&E, they also hope to pressure Gov. Jerry Brown and Lt. Gov. Gavin Newsom.

Newsom chairs the California State Lands Commission, which has jurisdiction over the state’s coastal tidelands. The intake and outflow chutes for Diablo’s cooling system lie on tidelands owned by the state and leased by PG&E, with the leases set to expire in 2018 and 2019. In June, the commission is expected to decide whether to require a full environmental impact report from PG&E before extending the leases. Without those leases, the cooling system and hence the plant would shut down.

At a December meeting of the commission, Newsom predicted Diablo wouldn’t remain open past 2025.

Hoff, Zaitz and their allies are planning a march from the Bay Area to Sacramento in advance of the commission’s June 28 meeting, ending at the home of Gov. Jerry Brown. The governor, who in the 1970s tried to prevent Diablo from opening, has remained quiet about its future. His press office declined to comment for this story.

“If we were to take Diablo Canyon offline, we would lose a quarter of the state’s clean power right now, and we’d replace it with (natural) gas,” Zaitz said. “For a state that’s so proud of its efforts against climate change, that’s unacceptable.”

Diablo supplies roughly 8 percent of all the electricity generated within the state, and it does so without pumping greenhouse gases into the atmosphere. The plant’s supporters — including another group that formed this year, Save Diablo Canyon — cast it as indispensable to California’s climate fight.

Opponents of the plant remain unconvinced. They consider the danger of meltdown too great, particularly considering the number of nearby fault lines. And the large, unchanging amount of power Diablo places on the grid day and night, critics say, crowds out electricity from the state’s fast-growing collection of solar- and wind-power facilities.

Opposing mothers

“We’re in favor of free speech, so this group has a right to exist and get their message out,” said Jane Swanson, a spokeswoman for the nonprofit Mothers for Peace, which has opposed Diablo Canyon since the early 1970s. “I wouldn’t put them down for it. Of course, we disagree with their positions, totally.”

Hoff and Zaitz both say they spent years considering the pros and cons of nuclear power before becoming convinced of its safety. And they understand that their advocacy places them in a strange position with their employer.

In conversation, they take care to mention, repeatedly, that they’re speaking on their own and not as representatives of PG&E. The company, they say, has not contributed funding to Mothers for Nuclear, a point echoed by PG&E spokesman Blair Jones. Then again, the company isn’t going to discourage them either.

“We’re not going to tell them what to do with their free time,” Jones said.

Should they fail, Hoff and Zaitz would need to find other work. But they might keep the group going, regardless.

“If (Diablo) closes and we both lose our jobs, than maybe we’ll go become full-time nuclear advocates and make sure this doesn’t happen elsewhere,” Hoff said.