Permanente Quarry

Waste quarry material piled over natural "Permanente Ridge" is visible from much of the South Bay.

A view of Lehigh Southwest Cement's Permanente Quarry looking north from the summit of Black Mountain across the quarry and over Silicon Valley

The Permanente Quarry is a limestone quarry located just west of Cupertino, California.^[1] The quarry is a limestone and aggregate mining operation and cement plant, owned by Lehigh Southwest Cement, a subsidiary of HeidelbergCement. Located in the foothills above Cupertino on the northeast slopes of Black Mountain, the quarry runs east-west parallel to the upper watershed of Permanente Creek to the south and to Permanente Ridge and Rancho San Antonio Open Space Preserve to the north.

The limestone rock found in the Permanente Creek valley and on the summit of Black Mountain is relatively unique in the Bay Area. Microfossils in the limestone deposits suggest that the mountain originated as a seamount at 22 degrees north in the tropical Pacific about 100 million years ago and was transported to Los Altos by the Pacific Plate.^[2][3][4] These rocks occur as jagged gray boulders and outcrops just southwest of the radio towers on the summit of Black Mountain, as well as in the Permanente Quarry. Calera is the Spanish word for 'limekiln', reflecting how limestone was burned historically to produce lime, an key ingredient for mortar.^[5]

History

The quarry was originally founded by Henry J. Kaiser as the Kaiser Permanente Cement Plant in 1939, taking the name of the business from the Permanente Creek in whose valley it lies. Kaiser intended to use the quarry to provide the majority of the cement used in the construction of the Shasta Dam, supplying the 6 million barrels (950,000 m³) of cement .^[6] The cement plant is the sole reason for the lone railroad line that runs through the city.

2011 shooting

On October 5, 2011, the Lehigh Southwest Cement plant was the site of a shooting committed by a disgruntled employee, 47-year-old Shareef Allman. During a safety meeting at 4:00 a.m., Allman opened fire with a .223-caliber semiautomatic rifle and a .40-caliber handgun, killing three coworkers and wounding six others. At 7:00 a.m., he attempted to carjack a 60-year-old woman five miles away at a parking lot of Hewlett Packard's campus, and shot her in the leg. She was hospitalized in fair condition. Multiple schools in the area went on lock down. On October 6, at about 7:30 a.m., police confronted a man who fit the description of Allman hiding behind a car parked in front of a house in Sunnyvale. Allman was asked to put his hands in the air by officers, and raised his handgun, making a comment asking to have himself killed. Sheriff's officials said Allman made a threatening motion at three sheriff's deputies, who responded with gunfire. An autopsy showed that Allman's fatality was caused by his self-inflicted gunshot wound.^{[7][8][9][10][11]}

Pollution

Mercury emissions

The cement plant at the quarry has been fueled by petroleum coke since 2007, the latter (along with the limestone itself) is a major source of mercury emissions. The cement plant is responsible for 29% of total Bay Area airborne mercury emissions and was shown to impact a rural site, Calero Reservoir, 20 miles (32 km) away.^[12] Mercury, a neurotoxin and pollutant which is concentrated in the aquatic food web, was found to be 5.8 to 6.7 times higher in precipitation near the cement plant than at a control location 2.0 miles (3.2 km) away.^[13]

Selenium discharge

Groundwater fills the current quarry and is pumped into Permanente Creek. Selenium pollution in the creek downstream from the quarry ranged from 13 to 81 micrograms/liter (μg/L). A North Quarry water sample in January 2010 had a dissolved selenium concentration of 82 μg/L, indicating that the quarry is the source of the selenium pollution. Selenium is bioaccumulated in the aquatic food web.^[14] Safety standards for selenium concentrations in fresh water are 5 μg/L under the California Toxics Rule (same as the National Toxics Rule set by the U.S. Environmental Protection Agency (USEPA) in 2000 and 2012.^[15]

Sediment discharges

Anthropomorphic activities related to quarry operations and the cement plant have resulted in sediment discharges into Permanente Creek that are 3.5 times what would be expected under normal conditions.^[16] Sediment loads in the upper Permanente Creek mainstem are 15 times those in the West Fork Permanente Creek, which drains mostly parkland. These sediment loads could threaten the resident rainbow trout (Oncorhynchus mykiss) population in the creek.^[17]

Controversy

Under the terms of a 1985 reclamation plan, the quarry was not supposed to dump quarry waste materials more than 100 feet higher than the natural chapparal ridge known as Permanente Ridge. This waste material storage area, or WMSA, was piled on and above the Permanente Ridge and this brownish-gray scar is visible from much of the southern Bay Area - despite claims from the 2004 owner, Hanson Cement, that it was hydroseeded annually with native grass mix and that they planted 80% of the area in trees and shrubs, it remains (see photo inset) a barren zone, degrading the aesthetic value of the adjacent Rancho San Antonio Open Space Preserve.^[18] This barren ridge line, referred to by Lehigh Southwest as the West Materials Storage Area (WMSA) is visible to much of the Silicon Valley.

On December 19, 2011, the Sierra Club sued Lehigh Southwest Cement Company^[19] and Heidelberg Cement in federal court to stop its unpermitted discharges of selenium and other toxic water pollutants into Permanente Creek. The Sierra Club maintains that Lehigh has been polluting Permanente Creek in violation of the clean water act for years. Lehigh's own water quality analyses have demonstrated that quarry pit wastewater that Lehigh discharges into the creek has been 16 times higher than Clean Water Act stream standards. The pollution is especially harmful to aquatic life in downstream areas such as Rancho San Antonio County Park, where selenium concentrations are often more than five times more dangerous than state and federal standards allow.

On June 7, 2012, the County of Santa Clara Board of Supervisors approved amendments to the 1985 Permanente Quarry Reclamation Plan for Lehigh Southwest Cement Company, including approval of a new waste material storage area (EMSA) at the east end of the quarry. The newly approved Reclamation Plan has 89 conditions (significantly more than the 73 conditions in the 1985 Amendment), and calls for higher performance standards for re-vegetation of all disturbed areas, minimizing selenium runoff and an increased level of reporting and monitoring. The Board also ratified the Final Environmental Impact Report in accordance with the California Environmental Quality Act.^[20]

In December 2012 the Midpeninsula Regional Open Space District has filed a lawsuit against Santa Clara County, challenging the reclamation plan for Lehigh Southwest Cement's Permanente Quarry near Cupertino, saying its environmental impact report failed to analyze and mitigate the project's impacts on air quality, hazardous materials, recreation, groundwater and endangered species.^[21]

See also

• HeidelbergCement

References

External links

• Map images of the quarry.
• Committee for Green Foothills (group against expansion of the quarry)
• News article about the cement plant
• Information on the City of Cupertino Website

Coordinates: 37°19′11″N 122°06′49″W / 37.319627°N 122.113552°W / 37.319627; -122.113552