CUPERTINO (KPIX 5) — Santa Clara County is preparing for a legal battle with the Lehigh Hanson cement company near Cupertino over the rights to develop a hilltop directly adjacent to the Rancho San Antonio County Park, one of the most popular outdoor destinations in the South Bay.

Lehigh Hanson has submitted a proposal to the county to remove a section measuring 100 feet tall by 4,000 feet wide along a highly visible stretch of the ridgeline facing the main entrance to the park.

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“There is a clear and present danger that we’re gonna lose those hillsides,” said County Supervisor Joe Simitian.

According to county staff calculations, the proposed area encompasses 20 acres, amounting to 15 million cubic yards of soil, enough to fill 1.875 million cement trucks.

However, an easement voted upon and approved by the county in 1972, has provided legal protection for the hilltop and surrounding lands for nearly 50 years, according to Simitian.

“They’re litigating with our county, whether or not our county has a right to review and establish the nature and extent of their vested rights,” said Simitian. “There is a legally binding commitment to protect that hillside in the public’s interest. And my expectation is that legally binding instrument will be honored and enforced.”

Simitian has amassed a growing list of supporters, including Cupertino Mayor Darcy Paul, Los Altos Mayor Neysa Fligor, Green Foothills, the Sierra Club, Teamsters Local 853, Operating Engineers Local 3 and Midpeninsula Regional Open Space District.

Next Tuesday, the Santa Clara County Board of Supervisors will vote on a proposal to partner with Midpeninsula Regional Open Space District — also known as Midpen — to share enforcement and protection responsibilities with the agency.

“One of the ways we can make sure we don’t lose those hillsides is by having reinforcements at the ready, and that is the good folks at Midpen,” said Simitian.

“You can be sure that we’re going to be paying a lot of attention,” said Midpenisula Regional Open Space District Board Director Yoriko Kishimoto.

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Simitian said the company’s behavior has become a concern over the past year.

“They are increasingly aggressive — and then frankly, increasingly surprising — in terms of efforts to be a good neighbor. And that disappoints me,” said Simitian.

Simitian said Lehigh has not been forthcoming during the application process and speculated about the company’s motives in its efforts to “chop the top” of the hill.

“I think that what we’ve got is a played-out quarry and facility. An application that is designed to provide additional economic opportunity there, which would add value to the property if Lehigh then got those permits and entitlements and marketed it to a new owner,” said Simitian.

Late Thursday, Erika Guerra, Environmental and Land Resource Management Director for Lehigh Hanson’s West Region offered this statement:

Lehigh agrees with the importance of protecting our precious natural resources, including the ridgeline in our Quarry. We have demonstrated this commitment by submitting an amendment that will preserve the easement. Our proposed solutions were developed by geotechnical experts to preserve it for the long term and include enhanced revegetation and stability. To be clear, the easement will remain.

While Lehigh has not had the opportunity to review the specifics of the County’s proposal to involve the Midpeninsula Regional Open Space District (MOSD), we value the expertise that MOSD can provide to the technical review of our reclamation plan application and hope that the process can begin in earnest.

Despite statements made to the contrary, Lehigh has proposed solutions to the ridgeline through our current application. The County is blocking the application by attempting to challenge its own final determination of our long-established vested rights which were also upheld by the Courts.

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The County must stop delaying the robust environmental review and community outreach process we have initiated and move forward on our application.