(CN) – The Trump administration took the first step Wednesday to open more than a million acres of public land in central California to oil drilling and fracking, raising concern among conservationists seeking to protect water sources.

In 2013, California established a moratorium on leasing federal public land in the state to oil companies that use fracking technology to find oil.

The Bureau of Land Management published a notice Wednesday in the Federal Register seeking public comments on its proposal to review the use of hydraulic fracking on public lands in Fresno, Kern, Kings, Madera, San Luis Obispo, Santa Barbara, Tulare and Ventura counties.

Fracking is an oil-extraction process that blasts a mix of chemicals and water underground to crack rocks. Scientists have associated increased seismic activity with fracking, while environmentalists say the wastewater is a threat to wildlife and public health.

California is one of the nation’s largest oil and gas producing states with nearly 8,000 oil and gas wells.

The potential drilling sites are located in areas encompassing 400,000 acres of public land and an additional 1.2 million acres of federal mineral estate, according to the notice published by the agency’s California Director Jerome E. Perez.

The agency said in the notice that it will consult with wildlife biologists, geologists and other experts in the planning process. American Indian tribal governments will be consulted to determine whether oil drilling will impact cultural artifacts and tribal lands, the notice said.

“It’s great that BLM is finally going to look at this problem,” said Greg Loarie, an attorney at conservation group Earthjustice. “But analyzing the impacts of fracking is like analyzing the impacts of smoking cigarettes: there’s really no question that more fracking would be terrible for California.”

Wednesday’s notice alarmed other conservationists who see the move as an escalation in the ongoing feud between the Trump administration and the Golden State.

The BLM rescinded an Obama-era law regulating fracking, claiming the rules unnecessarily burdened energy companies and stunted economic growth.

California responded by suing the Trump administration in January over its attempts to loosen restrictions.

“This step toward opening our beautiful public lands to fracking and drilling is part of the Trump administration’s war on California,” said Clare Lakewood, an attorney with the Center for Biological Diversity. “We desperately need to keep these dirty fossil fuels in the ground. But Trump is hell-bent on sacrificing our health, wildlife and climate to profit big polluters.”

An agency spokesperson did not immediately respond to a request for comment.

A 2015 lawsuit against the BLM filed by the Center for Biological Diversity and EarthJustice found that the agency unlawfully approved a resource management plan – allowing oil and gas drilling and fracking on vast stretches of California’s public lands – without adequately analyzing and disclosing the impacts on air quality, water and wildlife.

As part of a legal settlement, the agency agreed to complete a new analysis on the environmental impact before deciding whether to allow drilling and fracking on public land across California.

The BLM has not held a lease sale in California since 2013 when a federal judge first ruled that the agency had violated the National Environmental Policy Act by issuing oil leases in Monterey County without considering the environmental dangers of fracking.

A 2015 report from the California Council on Science and Technology concluded that fracking in California happens at unusually shallow depths, dangerously close to underground drinking water supplies, with unusually high concentrations of chemicals, including substances dangerous to human health and the environment.

In July, residents of San Luis Obispo, a city in California’s central coast, placed a voter initiative on the November election ballot that, if passed, would ban fracking and new oil and gas wells in San Luis Obispo County.

The period for submitting comments ends Sept. 7.