By Alice Kaufman and Lennie Roberts

Pilarcitos Quarry

The Pilarcitos Quarry, located off Highway 92 in Nuff Canyon, three miles east of Half Moon Bay, is a granite quarry that produces rock, sand and gravel (called “aggregate” in the construction industry). Although Pilarcitos Quarry has been in operation since 1933 and thus predates San Mateo County’s permit requirements, the quarry has always obtained the necessary county permits rather than arguing that it has a vested right to mine without local  permits.  

When the Pilarcitos Quarry proposed expansion of the existing quarry, the owners contacted CGF and asked for advice.  Their initial plan was to expand quarry operations throughout the pristine upper canyon, which would have committed the entire 588-acre property to mining.  Due to concerns CGF and agencies had over impacts on wildlife and sensitive habitats, the quarry revised their plan to limit expansion to a much smaller 107-acre footprint.  Additionally, the quarry agreed to (1) grant a conservation easement permanently protecting 192 acres in the upper canyon; (2) create new habitat for the threatened California red legged frog; (3) “daylight” and restore Nuff Creek, which currently runs through a concrete culvert; and (4) capture rainwater to release into the creek during the dry season for the benefit of endangered steelhead trout and other species.

Pilarcitos Quarry’s expansion was approved by the County Planning Commission in January 2012, and no environmental groups or public agencies appealed their decision.

Lehigh Permanente Quarry

The Lehigh Permanente Quarry is located in Santa Clara County, in the foothills next to Cupertino,directly south of Rancho San Antonio Open Space Preserve. The quarry produces limestone aggregate and also operates a cement plant.

Because of the high levels of mercury and selenium present in the limestone at the quarry site, Lehigh’s operations result in significant mercury air emissions from the cement plant and selenium discharges to Permanente Creek, which runs through the property. The quarry’s location directly adjacent to the residential neighborhood of Cupertino has resulted in years of complaints and protests from local residents about the dust and pollutants emitted by Lehigh’s cement plant, the noise of the truck traffic, and other impacts from the quarry’s operations.

State agencies regulating air and water pollution have issued multiple notices of violation to Lehigh concerning the emissions and discharges from quarry operations. Lehigh filed suit in 2012 against the Bay Area Air Quality Management District (BAAQMD) over the air quality regulations applicable to Lehigh’s operations, alleging that since Lehigh is the only cement plant within BAAQMD’s district, the regulations were unfair. The quarry’s violations of the Clean Water Act, were the subject of a lawsuit by the Sierra Club that was settled in early 2013 when Lehigh agreed to reduce its discharges of selenium to Permanente Creek down to legal levels.

Meanwhile, a lawsuit by the Mid-Peninsula Regional Open Space District (MROSD), which manages Rancho San Antonio Open Space Preserve adjacent to the quarry, alleges that Lehigh’s recently completed Reclamation Plan Amendment (which details the actions the quarry will take to clean up the environmental damage from its mining operations) is inadequate and fails to address the impacts to air quality as well as the dangers from toxic metals and contaminants present in the soil from the munitions and metal manufacturing operations formerly conducted at the quarry site. Yet another lawsuit, by Bay Area Clean Environment, challenges the decision by Santa Clara County that Lehigh has vested rights to mine on this site and therefore does not need to obtain a County Use Permit for its operations.

Are All Quarries Created Equal?

With all industrial land uses, the question arises: is it better to prohibit the activity completely or to allow it in appropriate locations? When it comes to mining of aggregate material, basic maintenance of roads and structures in the Bay Area requires either production or importation of some amount of aggregate. Having a local production source for this material can reduce greenhouse gases and air pollution that would result from importing the material (aggregate imports generally come from Mexico or Canada).

Given that mining of aggregates will take place in the Bay Area, what limits should be placed on these activities? Should we encourage mining in mineral deposits such as the limestone of Lehigh Quarry, which contains toxic mercury and selenium, or in granite deposits in Pilarcitos Quarry, which does not have these contaminants?  Should we take into account actions such as those committed to by Pilarcitos Quarry to create new wetlands and stream habitat, including habitat for threatened California red legged frog, and permanently protect many acres of valuable land? Should we consider whether a quarry poses a health risk to local residents, or even simply whether its location relative to residential neighborhoods causes a nuisance from noise and dust?

Quarries may be necessary evils, but there can be little doubt that there are some quarry operations that are more environmentally friendly than others. It is impossible to ignore these thorny issues when advocating for the long-term protection of our environment and our open spaces. As we work towards a future in the Bay Area that embodies the values we have represented for over 50 years, CGF will continue to ask these hard questions and weigh competing issues, so that future generations may enjoy the beauty of our environment as well as clean air and water.