VENTURA, Calif.— The Ventura County Board of Supervisors on Tuesday will consider the expansion of the Pacific Rock Mine, an operation that would extract nearly 30 million tons of rock over the next 60 years. The action follows an appeal from the Center for Biological Diversity challenging the county planning commission’s approval of the mine expansion, which is located near the Conejo Grade.

“The region’s wildlife and wildflowers would take a massive and permanent hit if the board allows this poorly planned expansion,” said Evan Levy, an attorney at the Center. “I hope the board does the right thing and sends this project back to the planning commission to fix the faulty environmental review.”

What: Ventura County Board of Supervisors meeting

When: Tuesday, Oct. 20, 10:30 a.m.

Where: Ventura County Government Center, 800 S. Victoria Ave., Ventura. Meeting can be streamed at: venturacounty.gov/bosmeetings

Who: Representatives from the Center for Biological Diversity will be available for interviews.

Background

The area around the Conejo Grade, between Camarillo and Thousand Oaks, is a unique volcanic rock formation that hosts many plants found nowhere else on earth. The mine’s expanded footprint would slice deep into the county’s only pathway for mountain lions and other wildlife to move in and out of the Santa Monica Mountains.

The planning commission approved the project in June. In seeking approval, Pacific Rock repeatedly requested to delay the planning commission hearing because it had failed to fix a long-standing grading violation. In the early 2010s the mine operated without a valid county land use permit and racked up multiple violations.

The county’s environmental review studied a mine expansion that would last 30 years. But the applicant changed the permit term to 60 years after admitting to a math error to determine how much rock it would extract. The county failed to update the environmental review to account for the consequences of doubling the project’s lifespan.

The expansion would destroy multiple populations of the Conejo buckwheat, a flowering shrub species that grows only in southeast Ventura County. The project would also cut an essential corridor for wildlife movement from 1,500 feet wide to just 800 feet wide, deterring animal movement to and from the Santa Monica Mountains.

The expansion would result in 120 daily truck trips to haul rock, aggregate and other materials, which would result in significant climate and air pollution. The environmental study also found the expansion would have unavoidable, permanent impacts on the viewshed in southeastern Ventura County.

Under California environmental law, the board of supervisors cannot approve the mine expansion unless it finds that the project’s benefits outweigh the costs.