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Quarry waste material piled over natural ridge “Permanente Ridge” that borders the Permanente Quarry and Rancho San Antonio County Park, viewed from Quarry Trail and Black Mountain Trail intersection. Photo by Schmibel obtained via Wikimedia Commons under Creative Commons Attribution-Share Alike 3.0 Unported license.

A massive cement plant near Cupertino that has run afoul of regulators thousands of times will be shuttered permanently.

Lehigh Southwest Cement Company said it will not restart its cement kiln at its 3,510-acre Permanente Quarry and Cement Plant. The company’s property is located largely in the hills of unincorporated Santa Clara County, with portions of the site in Cupertino and Palo Alto.

Though the kiln has been shut down since April 2020, other operations will continue at the facility, the company said in a statement Monday. The cement plant opened in 1958, although limestone mining has been part of the site dating back to around 1939, according to the county and the company.

Santa Clara County Supervisor Joe Simitian, a leading critic of the plant’s regulatory violations and detrimental effects on the environment, said the closure announcement is encouraging and a step in the right direction.

Simitian said he is confident Silicon Valley can “continue to thrive” even as local cement production could be phased out. He pushed earlier this year for the county to acquire the plant and then shut it down, eyeing the possibility of converting the land back to a natural state.

“I think it’s good news, no question about it. I think there is still a lot more work to do to get us to the place we need to be,” Simitian told San Jose Spotlight. He said in a statement it no longer works to have a major industrial operation like a quarry and cement plant near suburban communities.

Santa Clara County has land use regulatory authority over the site, and the board of supervisors’ Housing, Land Use, Environment, and Transportation committee will discuss the future of the plant at a meeting Thursday.

In 2019, the company submitted an application to the county to expand its mining operations at the site, but now appears to be ditching that effort. Representatives announced the company wants to develop a “new reclamation plan amendment application” which it plans to submit, but details are unclear.

“There was a clear plan to expand mining at the quarry and the fact that that application appears to be abandoned is good news as well,” Simitian said.

Jeff Sieg, a spokesperson for the cement company, did not respond to requests for comment.

“The Permanente cement plant has made many valuable contributions to northern California over the years and we are now working on a long-term strategy for this site so that it can continue to provide value in the future,” Greg Ronczka, vice president of environment and sustainability for the company, said in a statement.

Simitian said the announcement still raises other questions that haven’t been answered yet.

“Is it possible to make sure the plant stays closed in perpetuity?” he said. “As always, the devil is in the details.”

Cement from the Lehigh site has been used to build major projects around the Bay Area and the state, including Mineta San Jose International Airport and the Golden Gate Bridge, the company said.

Environmental concerns

Cupertino Mayor Darcy Paul similarly hailed the announcement from Lehigh as much welcomed news, and he’s looking forward to possible future reclamation of the site.

“I think we need to keep in mind that the ecology has withstood quite a bit over the years,” Paul told San Jose Spotlight. “First and foremost, I would like to see the environmental and health related considerations put on the front burner.”

In May, the county, at Simitian’s urging, published a report that compiled all the known violations of local, state and federal laws the cement plant violated from 2012 through 2021.

The report revealed more than 2,100 violations, with more than 100 considered serious violations, while others ranged from minor reporting errors to failed inspections of portions of the company’s diesel truck fleets.

The company was fined more than $12.7 million over that decade for various alleged violations, including the discharging of wastewater into Permanente Creek and excess emissions that worsened air pollution.

Brian Schmidt, policy and advocacy director at preservation group Green Foothills, said he hopes to see the county pin some legal requirements to the company following this announcement, to ensure the kiln stays shut off for good.

He said while the work in the quarry has caused damage to hundreds of acres left in a condition that resembles a “moonscape,” he’s hopeful for future possibilities of reclaiming the land.

“While that’s horrible, the opportunity for restoration for that amount of land is tremendous,” Schmidt told San Jose Spotlight. “I don’t think there will be another opportunity for upland environmental restoration of that scale in Santa Clara County again.”

This story, from Bay City News Service, was originally published by San Jose Spotlight.

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6 Comments

  1. Since we will still be using cement here, it will now presumably be trucked in long-distance. Do Simitian and Schmidt plan to organize bicycle convoys with cargo trailers to bring in the cement in a “sustainable” way?

    Perhaps the homeless have the right idea of living in tents rather than concrete buildings. 🙂

  2. The blight in the Foothills has been an eyesore since I moved here in 1970.
    I cannot believe that the Cement company’s projects’ positives over comes the environmental negatives it creates. It’s about time to close it for good as we try to fight climate crises all over the world.

  3. We’ll still need cement. Of course. It’s too bad a way couldn’t be found to make this the best possible operation on the planet. The environmental impacts of mining and cement making will just be shifted to other communities with the added costs and impacts of shipping very heavy material over longer distances. Does anyone know where these materials will come from now?

  4. Ah, the memories! I worked for Kaiser Electronics for 27 years and it started when I accepted the engineering position in January, 1964. Our plant was up the hill (Page Mill Road) above HP on the corner of Porter Drive. We were a wholly owned subsidiary of Kaiser Industries. I remember those big pink Kaiser Permanente cement trucks rolling down highways in this area and the motto painted on them, “Find a need and fill it”. We adopted that motto as well, and became the world’s leader In avionics display systems. I was privileged to lead the design team that developed the
    F-18 head-up display (HUD). I know there’s always the controversy about the “Blue Angels” but I still take pride when I see them fly and when I see videos taken from inside the cockpit looking through the HUD combing glass assembly in front of the pilot.

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