California’s air regulator said Friday that the benefits of a proposed overhaul to a core state climate program significantly outweigh the associated costs, including potential gas price increases, despite growing concerns over their impact.

“It’s a win-win,” said Air Resources Board executive Officer Steven Cliff on the proposal in a media briefing Friday. “We get public health benefits, we reduce health costs, we see lower costs of driving and we help turbocharge those investments in clean energy infrastructure that helps drive our zero emissions future.”

The air board, which faces a November 8 vote to tighten the Low Carbon Fuel Standard, has faced recent criticism over a perceived lack of transparency on potential gas price increases. The outcry was initially driven by Republican lawmakers, who pushed to delay the vote.

While intended to quell criticisms, Cliff’s statements may only fuel a growing political firestorm on the program’s future. The escalating debate highlights how rising fossil fuel costs for millions of Californians could threaten the state’s ambitious climate agenda.

Established in 2011, the Low Carbon Fuel Standard is a $2 billion credit trading program that requires fuels sold in the state to become progressively cleaner and offers financial incentives for companies that produce lower-emission options, such as soybean-based biofuels or cow manure.

The air board has been working to strengthen the program to meet the state’s fast approaching climate targets. Proposed reforms could cut carbon dioxide-equivalent gases by 558 million metric tons through 2046, according to CARB’s estimates.

But with costs of living and energy prices top of mind for Californians this election year, gas prices have dominated criticism of the LCFS ahead of the upcoming vote.

The agency said earlier this month that fuel producers in California typically pass 8 to 10 cents per gallon of costs to consumers as a result of the program. But estimates for how the board’s proposed changes would affect gas prices vary.

In an initial assessment released last year, the air board projected that the changes could raise the price of gasoline by 47 cents per gallon next year and of diesel by 59 cents. Agency officials have since disavowed that estimate.

Another report released earlier this month by the University of Pennsylvania’s Kleinman Center for Energy Policy predicted that the cost of gasoline would increase by 85 cents a gallon through 2030.

Cliff, CARB’s executive officer, said the agency could not predict gas price impacts of the program with any certainty.

Putting a number on gas prices is difficult because companies have different strategies for complying, he said. Some might produce cleaner fuels themselves, potentially profiting from the incentives, while others may buy credits on the market, which could lead to unpredictable costs.

Critics say the agency is failing to take into account the financial impact of its climate policies on consumers.

“It feels like they don’t care,” said state assemblyman Joe Patterson, R-Napa, on the agency’s refusal to estimate gas price impacts. “They have the tools to be able to do this but they’re choosing not to.”

Republican lawmakers have also criticized Gov. Gavin Newsom in recent weeks, after he declared victory over Big Oil during a special legislative session. On Thursday, California Republicans in the U.S. House of Representatives also urged a delay on the air board’s plan.

Apart from gas prices, the LCFS has faced significant criticism from environmental groups who say the program was developed in an era before widespread availability of zero-emission options, and that it supports polluting industries such as biofuels and dairy methane.

CARB’s own environmental justice committee recently urged the Air Board to reject the update, saying the program would “exacerbate and entrench pollution in environmental justice communities.”