SAN JOSE, Calif. (KGO) -- Across the country, many are awaiting an announcement from the Environmental Protection Agency, that could loosen regulations aimed at requiring automakers to nearly double the average fuel economy of new cars and light trucks to more than 50 miles per gallon by 2025.
The potential changes, which could be announced next week, are alarming to some.
"Cars are 70-percent of our unhealthy air," says Terry Trumbull, SJSU Environmental Studies Professor. "We've got to have cleaner burning cars, and the cost of it is trivial. In a new car, it is virtually nothing."
Under the 1970 Clean Air Act, California has special authority to enforce stronger air pollution standards than those set by the federal government, because the state set its own regulations before federal rules came into play. But environmental experts say the Trump administration could eventually take California to court to take away that right.
This week, Attorney General Xavier Becerra wrote on Facebook: "We're prepared to take whatever action, legal or otherwise, that we must to protect our economy, our environment, and the public health of people of California."
"50-percent of everyone in the U.S. lives in areas where the levels of air pollution are unhealthful, and 95-percent of Californians live there, so we know that regulation works," says Margo Sidener, Breathe California of the Bay Area acting executive director.
But by lifting what some refer to as a regulatory burden, the EPA is expected to argue that automakers and consumers both stand to benefit as larger cars and trucks become more popular.
In a blog post on Medium, Ford Executive Chairman Bill Ford said: "We want one set of standards nationally, along with the additional flexibility to help us provide more affordable options for our customers."
However, there is growing concern that if the U.S. were to loosen its restrictions, automakers could then push for more lenient standards elsewhere around the world, causing more pollution by vehicles.
Click here for more automotive stories, photos, and video.