CUPERTINO, Calif. (KGO) -- The historic Lehigh Cement Plant in the hills near Cupertino will shut down permanently and never reopen.
On Tuesday, the Santa Clara County Board of Supervisors approved a legally binding agreement with the plant's two parent companies.
The plant is located in Santa Clara County Supervisor Joe Simitian's district.
"If someone else buys it, if there's a change in business plans, if there's a new leadership at the company, the plant still stays shut," Simitian said.
Simitian describes this as a 'once and for all' arrangement.
The cement plant operated for more than 80 years -- the limestone quarry has been there more than a century.
"We have the commitment to shut down the cement plant, we have the commitment to stop the quarrying activity and now we can talk about restoring and reclaiming the site, which is 3,500 acres," Simitian said.
Lehigh has supplied the Bay Area with more than half of the cement it uses in constructing bridges and buildings, but not without problems.
"But this has been a real challenge environmentally, more than 2,000 violations over a 10-year period," Simitian said.
Simitian said those 2,100 violations range from small to big.
The environmental advocacy non-profit Green Foothills says the cement plant was the worst source of air pollution in the county.
Alice Kaufman is the Policy & Advocacy director for Green Foothills.
"The quarry was also a source of pollution for Permanante Creek. The quarry was discharging selenium into the creek which is a toxin that causes birth defects in wildlife. So the environmental harms were just enormous," Kaufman said.
Both the plant and the quarry are shut down, which may seem like an environmental victory but plans to restore and clean the site will take years.
"They've got a proposal in, it's called a Reclamation Plan Amendment that, not only talks about what they're going to do, but equally important talks about how they're going to restore the site when they wrap up their activities on the site, and that's probably going to take a couple of years," Simitian said.
Kaufman said the work to monitor the site is not done yet, but the legally binding agreement to cease cement production is a significant step forward to restore the 3,500-acre site.
"Then we're really hoping that it can be really restored to what it used to be. I mean, this quarry is surrounded by some of those beloved nature preserves in the county," Kaufmain said.
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