The measure was introduced in response to the state's rising gas prices. It will require oil refineries to keep a minimum inventory level of fuel to avoid supply scarcity and price hikes at the pump. Additionally, it will authorize the California Energy Commission to approve scheduled maintenance times to avoid supply issues.
In fiery remarks after signing the bill, Newsom slammed the oil and gas industry for what he called "manipulative" marketing practices.
"You're seeing gas prices drop across the rest of the country. But spike in California. And they buy all these ads saying somehow it's California's fault," the Democratic governor said. "They've been manipulating you, they've been lying to you."
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Earlier on Monday, the California Legislature gave Assembly Bill X2-1 its final approval in a 41-16 vote, with several Democrats not voting and four of them voting against the bill.
Proponents say it will stabilize gas prices and save California drivers more money overall. Opponents argue the storage requirements might be unfeasible for refineries and could lead to refinery closures and job losses.
During his press conference, Newsom specifically called out the Western States Petroleum Association, which represents companies that produce, refine and transport the bulk of gas in Arizona, California, Nevada, Oregon and Washington.
"Particularly WSPA and their talking points and Big Oil that knowingly continues to lie to the people of this state and our nation," the governor said. "They are the polluted heart of this climate crisis. They continue to lie and they continue to manipulate."
WSPA president and CEO Catherine Reheis-Boyd has been vocal about her strong opposition to the bill.
"In our opinion, we should be looking at critical issues like production of crude oil in the San Joaquin Valley," she said. "That crude oil goes to refineries to make gasoline, diesel and jet fuel. We have a lot of it, but we can't get it because the state of California won't give us permits."
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Reheis-Boyd told ABC7 she doesn't feel as though California has been a willing partner with the petroleum industry in discussing how to strike a balance between renewable and non-renewable energy sources.
"We want to make sure that we can continue to provide reliable fuels in the traditional sense, ever cleaner every day, as we're moving towards a diversified energy portfolio," she said. "But what we're talking about here is how do you get from one to the other and not have unintended consequences? And right now, that track of liquid fuels and electrons is not matching up. Demand is not going down at the level they think it is."
Reheis-Boyd said she'd like to see the state focus on fees and taxes drivers pay on gas in California, rather than these mandates for the state's nine refineries.
This bill was the result of two special sessions Newsom called in order to get it passed after the measure failed to make it through by the end of this year's regular legislative session.
Newsom said now that the bill is signed into law, the CEC will meet to assess the supply and demand of the oil and gas market, as well as health and safety concerns for refinery workers before drafting standards for refineries to follow.
"Now we have the tools and we're providing a process where the CEC will deeply analyze all the considerations and concerns," he said.
Following Newsom's new conference, WSPA released a statement that read in part:
"Instead of offering real solutions, the Governor chose to demonize an industry that powers California's economy and fuels the daily lives of millions. This kind of inflammatory language won't lower gas prices, fix the energy crisis, or help the state achieve its climate goals. In fact, the administration's refusal to address the complexities of the industry during legislative hearings-where even its own experts admitted they didn't have answers-shows a clear disconnect between rhetoric and reality."