What environmental issues do 1.7 million neighbors of the Lehigh Southwest Cement plant and quarry want studied as the company plans a new 210-acre pit mine in the foothills just outside Cupertino, Los Altos and Los Altos Hills?
Santa Clara County planners want to know. They will host a meeting called a “Public Scoping Session” Wednesday from 7-9 p.m. in the Cupertino Room of the Quinlan Center, 10185 N. Stelling Rd. Planners say they want to hear what information citizens think should be included in an environmental impact report (EIR).
In addition to the proposed pit mine, the report will also address a reclamation plan amendment to the quarry's 1985 Reclamation Plan. A reclamation plan addresses how the land will be eventually be "reclaimed."
Interest in Lehigh’s activities has grown over the last several months, and recent public meetings have been packed. The –during which supervisors voted to give the company vested rights for mining activities on most of its land—was standing room only, with the crowd overflowing to a neighboring room.
Some of the environmental issues that will most likely come up at Wednesday's meeting include the following:
- Visual impact: A portion of the new pit mine will be visible from the valley floor, according to a planning report. Specifically, planners said they want to know from citizens which viewpoints should be used in the EIR for a visual impact analysis.
- Water quality: (NOV) by the California Regional Water Quality Control Board charge that “Lehigh discharges hundreds of thousands to millions of gallons per day of unpermitted, non-storm water” into Permanente Creek. The board said that silt and sediment from quarry practices is flowing unfettered into the creek. Lehigh officials have denied the charges. The same NOV report stated that Lehigh is exceeding the limits of selenium discharged into the creek and has not adequately addressed how it will control the toxin. Selenium has been shown to cause problems in fish and wetland birds.
- Air quality: The EIR will explore how dust generation and emissions related to mining may affect the surrounding atmosphere. The cement kiln is a separate operation so the EIR will not explore the impacts of those emissions. Expect citizens and watchdog groups to bring up the cement kiln on Wednesday anyway, because the quarried limestone is burned in the neighboring cement kiln, emitting mercury and other toxins into the air.
- Geology and Soils: The water board report and testimony given at a recent State Mining and Geology Board meeting calls into question how past owners controlled erosion and slope stability of the piles of unused quarry rock, called “overburden."
- Reclamation: How Lehigh reclaims the quarried land will be addressed in the EIR. One issue local environmental groups have complained about in the past is that owners have not adequately reclaimed land in what’s known as the West Materials Storage Area, located closer to Los Altos Hills. Lehigh officials have said they are taking steps to improve the look of the area, but that it will take time.
In addition to exploring potential environmental impacts, every EIR includes “a range of reasonable alternatives,” according to the county report. Planners will consider “Reduced Scale,” as well as “No Project” alternatives.