Silicon Valley Is One of the Most Polluted Places in the Country

Microchip manufacturers contaminated the groundwater in the 1980s. Almost 40 years later, the cleanup still isn’t complete.

SEPTEMBER 22, 2019

Sometimes it feels hard to remember that Silicon Valley is an actual place, a collage of parched suburbs, and not just the collective noun for information-technology companies. But before it was the idea center of the internet, it was a group of factory towns, the blinking heart of “clean” manufacturing, the hallmark of the Information Age.

Silicon Valley was a major industrial center for much of the 20th century. Semiconductors and microprocessors rolled out of factories scattered all over the area (known on maps as Santa Clara County) from the 1950s to the early 1990s—AMD, Apple, Atari, Fairchild, Hewlett-Packard, Intel, and Xerox, to name just a few. From the mid-1960s to the mid-1980s, Santa Clara County added 203,000 manufacturing jobs, 85 percent of them in tech. Beginning in the 1980s, as government contracts disappeared, Silicon Valley companies moved toward creating software, and beginning in the 1990s, companies there largely focused on internet-based applications. Now the area trades mostly in the rarefied and intangible realm of apps and software.

It’s hard to see that now, when glass-walled office buildings, corporate campuses, and strip malls along highways that bloom into concrete clovers dominate the landscape of this former industrial area. But all of that industrial history left something behind.

This post was excerpted from Schlossberg’s recent book.
The Google Quad Campus looks way too nice to sit on top of an active Superfund site: There are matching bikes, a pool with primary-colored umbrellas, and a contained universe that looks more like a college or a park than a satellite campus of one of the biggest companies in the world.*

But it turns out that this idyllic garden of corporate harmony sits on land that since 1989 has been a Superfund site, a designation the EPA gives some of the most contaminated or polluted land in the country. And while thousands of tons of contaminants have since been removed, it is still being cleaned up. For a few weeks at the end of 2012 and into 2013, toxic vapors got into two campus buildings, possibly exposing the office workers there to levels of chemicals above the legal limit set by the EPA. A spokesman for Google said that while the pollution levels required remedial action, they did not necessarily put employees in danger. He added that the issue was resolved in less than four weeks.

Santa Clara County has 23 active Superfund sites, more than any other county in the United States. All of them were designated as such in the mid to late 1980s, and most were contaminated by toxic chemicals involved in making computer parts. Completely cleaning up these chemicals may be impossible.

The sites came to the attention of the EPA after groundwater testing in the area revealed that toxic chemicals—notably, a solvent called trichloroethylene—were present, possibly from leaking pipes or underground storage tanks. Trichloroethylene, which was used to clean semiconductors (a component of computer chips) during the production process, is associated with increased risk of certain cancers, developmental disabilities among children exposed in utero, increased rates of miscarriage, and endocrine disruption.

Back in the ’80s, IBM, Fairchild, and other companies accused of polluting the groundwater denied that the chemicals posed any sort of threat to human health. In 1985, a California Department of Health Services study reported a significantly higher than expected rate of miscarriage and birth defects near the leaking tanks, though the department did not have conclusive evidence to tie the health problems to the leaks. (Neither IBM nor Schlumberger Technology Corporation, the company responsible for cleanup at the former Fairchild site, responded to requests for comment.)

Over the past three decades, the EPA and the companies involved in polluting Silicon Valley’s groundwater have filtered and cleaned some of it, but the agency’s website acknowledges that the cleanup will continue for many decades. That’s in part because the toxic molecules have spread throughout the area—NBC Bay Area reported in 2014 that, according to government officials, there are 518 toxic plumes of groundwater in Santa Clara County, a number that advocates say is an underestimate.

The EPA maintains that there are no direct-exposure pathways to the contaminated groundwater anymore, but the problem now is that the toxins can get from the groundwater into the air in buildings via a process called vapor intrusion, which is what happened at Google. And while it’s not entirely clear yet what the consequences of lifetime environmental exposure are, research from South Korea suggests they may be serious. According to one study, Bloomberg Businessweek reported in 2017, miscarriage rates among women who worked at several South Korean microchip factories were nearly three times those of the general population. At one Samsung factory, two young women who worked next to each other were diagnosed with the same form of aggressive leukemia, a cancer that affects three out of every 100,000 South Koreans every year. The women died within months of each other.

Samsung said that it completely phased out a chemical linked to reproductive issues in 2011, but a 2015 study of another major chipmaker, SK Hynix, showed that workers there were still being exposed to harmful chemicals. The companies have yet to fully acknowledge that handling the chemicals negatively affects workers’ health, but both have privately paid employees and their families for illness or death, and Samsung has issued an apology. A Samsung spokesperson said the company’s semiconductor facilities “comply with the most stringent regulations” and stressed that “there has not been any study that confirmed a causal relation between the semiconductor working environment and risk of miscarriage.” SK Hynix did not respond to a request for comment.

On the surface, the health and environmental hazards of the tech industry seem separate from the way that we use machines in our everyday lives. Computers and cellphones—which require semiconductors and microchips to work—have become so essential to life all over the world that it’s easy to ignore the problems with building them. But the electronics industry is as much about chemistry—global chip manufacturers buy $20 billion worth of chemicals every year—as it is about computing. And even if we don’t think of our devices as having a backstory, or an impact beyond what they do to our eyes or brains, they do.

This post was excerpted from Schlossberg’s recent book, Inconspicuous Consumption: The Environmental Impact You Don’t Know You Have.

* This article previously mischaracterized the extent of the pollution at Google’s Quad Campus. The campus sits on land contaminated with toxic waste, but Google says the campus is not contaminated.

We want to hear what you think about this article. Submit a letter to the editor or write to

TATIANA SCHLOSSBERG* is an environmental reporter based in New York.

For the original article, please visit

*Tatiana Schlossberg is also the granddaughter of John F. Kennedy.

%d bloggers like this: