Our investigation tells the story of the toxic trail of unintended consequences left behind by the landmark federal Superfund program.
It’s a complicated story to report and tell. The Environmental Protection Agency doesn’t track these side effects. It considers them too difficult to measure. Companies, meanwhile, aren’t required to report where they send their waste. In many cases, data is incomplete or nonexistent. That forced us to piece together a story based on the best available documents, data, studies and scores of interviews.
Here are six important things to know about the reporting and storytelling.
1. Our story doesn’t cover the entire Superfund program.
There are more than 1,300 toxic waste sites in the Superfund program.
We zoomed in on a specific type of site. Scientific jargon alert: They’re called complex groundwater sites, which are polluted with volatile organic compounds. What that means: The groundwater is contaminated with hard-to-clean chemicals. Cleanup is complicated further by the fact that the ground underneath often is made up of many different types of soil and rock.
These account for roughly 850 Superfund sites. From there, we zoomed in even further to focus only on those using a specific type of treatment, called “pump and treat.”
There are two reasons why we focused on these sites. First, the technology used to clean them up is outdated and, in many cases, no longer effective. Second, the cleanup contributes tons of waste to the toxic trail every year. That means the effort can ultimately be for naught.
There are more than 450 sites like this – or about one-third of all Superfund sites. Many of the other sites don’t contribute to any toxic trail. They treat the waste on-site or use preventive measures to keep the pollution contained.
2. You can’t directly track Superfund waste beyond one step of the trail.
But you can track it step by step along the way to create an overall picture of the toxic trail.
Once waste leaves a cleanup site, it can go to one of thousands of treatment plants across the country. At those plants, the waste gets combined and treated with hazardous waste and other junk from all over the country.
On the other end, new waste gets created from that mix at treatment plants. In turn, it can then go to any number of sites, and so on and so on. You can’t paint one fleck of chemical from Silicon Valley red and track it through the system. But we showed the many different trails it can take.
3. Available data and documentation is spotty.
We often couldn’t get complete information for the system as a whole. We did find individual reports and data that provided windows into it. They helped us quantify problems and take a unique look into how these systems operate.
We focused heavily on the Calgon Carbon Corp.’s treatment plant in Kentucky, for example. We didn’t have complete figures on its carbon footprint. There were, however, well-documented estimates for greenhouse gas emissions for a similar plant in Arizona. So we used that to compile a composite picture of the carbon footprint along one leg of this toxic trail.
4. There are thousands of other sites like these outside of the Superfund program.
These are overseen by local, state and other federal agencies, and many face similar challenges. We didn’t dig into the efforts underway at these sites. Instead, we tracked a single type of waste leaving the Silicon Valley site.
5. Lots of people live around these sites.
In many cases, hundreds or even thousands of people live within a mile of a Superfund site. Nearly half of all Americans live within 10 miles of a Superfund site. The city of Mountain View, Calif., for example, is home to 75,000 people. They live above and around 13 Superfund sites. Here, people are understandably concerned about exposure risks and want to see the sites cleaned, regardless of the method.
The level of danger depends at each site.
In some cases, keeping contaminated groundwater out of the mouths of nearby residents is all that is required. But in others, there are concerns that nearby residents could be breathing in toxic vapors or radiation. The EPA’s website generally lays out the risks at each site using a 1-5 star system. One star means “beware” and five stars means “don’t worry.” You can find this information for every site on the EPA’s Superfund Site Information search page.
Yet, as our story showed, in many cases cleanup goals aren’t being achieved. And the risk of exposure is often limited.
6. We used “Silicon Valley” as shorthand for the site we focused on. But there are more than two dozen Superfund sites in Silicon Valley alone.
The area we focused on is a collection of three sites known as the Middlefield-Ellis-Whisman Study Area, or MEW for short. But that wasn’t fun to read or write. So we called it some variation of “the Silicon Valley site” throughout the story.
There are more Superfund sites in Silicon Valley’s Santa Clara County – 23 – than any other county in the United States. These are the only visible remnants of what was once a manufacturing hub for a burgeoning tech industry.
There are two reasons why we homed in on this site. First, it’s where we started our reporting more than a year ago, asking questions after toxic vapors leaked into office buildings.
Second, the site has been studied extensively. This left behind a lengthy paper trail that details how much waste has been removed, the pollution levels and cost estimates. These bits of information allowed us to tell a more nuanced and complete story about the cleanup effort and its shortcomings.
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