8 of 10 most polluted cities are in California

In the American Lung Association‘s annual “State of the Air” report released in April 2018, eight of the USA’s ten cities with the worst air pollution are in California.  According to the USA Today write-up on the report, “about 133 million Americans — more than four of 10 — live with unhealthful levels of air pollution, placing them at risk for premature death and other serious health effects such as lung cancer, asthma attacks, cardiovascular damage and developmental and reproductive harm. ‘We still have a lot to do in this country to clean up air pollution,’ said Lyndsay Moseley Alexander, director of the Association’s Healthy Air Campaign.  The report looked at pollution levels from 2014 to 2016. Ozone pollution was worse overall in this report than it was in last year’s report.”

On the Report Card, Mountain View is not listed by Santa Clara gets a C rating for Particulate Pollution and an F for Ozone Pollution.

USA Today quotes Lung Association President and CEO Harold P. Wimmer in explaining that “near record-setting heat from our changing climate has resulted in dangerous levels of ozone in many cities across the country, making ozone an urgent health threat for millions of Americans.” Smog forms on warm, sunny days and is made worse from chemicals that exit vehicle tailpipes and from power plant and industrial smokestacks. Warmer temperatures make ozone more likely to form.  “This adds to the evidence that a changing climate makes it harder to reduce ozone pollution and protect human health,” Alexander said.

Did You Know?

Lehigh Permanente Quarry and Cement Plant west of Cupertino is the only cement plant of the top polluting plants in the U.S. that is directly adjacent to a major population center, located within a 5-mile radius of Los Altos Hills, Los Altos, Cupertino, Mountain View, Sunnyvale and Saratoga. [1] The adjoining quarry, owned and operated by the same company, supplies the limestone used in cement production at the plant. The limestone in this quarry, is particularly high in mercury, [3] a powerful NEUROTOXIN that is especially dangerous to children’s developing brains.[4] Lehigh has a long history of violations in air, water, land, and employee safety regulations from local, state and federal regulatory agencies. [5] In 2010 alone, Lehigh received 185 mining safety violations from the Department of Labor. [6]

Silicon Valley Residents Form Bay Area for Clean Environment
In December 2010, local citizens formed BACE (Bay Area for Clean Environment), a non-profit dedicated to informing Silicon Valley residents about the health and environmental dangers of mercury and other forms of pollution. BACE is working hard to ensure that Lehigh is operating in full compliance with all existing regulations.

Recent actions


On May 27, 2011, BACE filed a lawsuit against Santa Clara County and Lehigh Southwest asking the court to throw out a March, 2011 decision by the County Board of Supervisors granting vested, or grandfathered, mining rights to Lehigh. The Board’s decision, which went against its own staff’s recommendation, allows Lehigh to expand mining activities without applying for a use permit that would place reasonable limits on its operations. [7]


According to AB3098, quarries in violation of California mining laws cannot supply building materials to government-funded projects. Lehigh has been in violation of state mining laws for more than a decade yet remains on the AB3098-list of approved quarries and has received lucrative government contracts. Finally on July 20, 2011, the state acted to remove Lehigh from AB3098. [8] According to the Los Angeles Times, more than 28,000 signatures on a BACE initiated petition compelled the state to take rare action to hold Lehigh and Santa Clara County (as the lead agency) accountable.


On August 24, 2011, the Sierra Club issued a notice of intent to sue Lehigh and its parent company Heidelberg Cement Group for significant violations of the federal Clean Water Act.  According to the notice, Lehigh is liable for illegally discharging millions of gallons of polluted quarry water, high in selenium and other pollutants, as well as tons of mine tailings into Permanente Creek. The notice states that the pollutants enter the Santa Clara Sub-basin aquifer, which is the primary source of drinking water for San Jose and surrounding cities. [9] BACE is supporting this action.

We are Making A Difference.
With Your Help, We Can Do More!

Lehigh is doing everything in its power to avoid being removed from AB3098, including filing a suit against the state to stop its enforcement of the law. [10] On the national level, the head of Lehigh’s parent company has urged Congress to block enforcement of new EPA pollution standards for cement plants. [11]

Community organizing makes a difference, even in the face of powerful interests. BACE will continue to pressure the State and other regulatory agencies to vigorously defend the public’s interest and hold Lehigh accountable.

Please contact your elected officials to express your concern about this issue and please join our mailing list to stay informed.

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