By Erin Sherbert
By Erin Sherbert
By Leif Haven
By Erin Sherbert
By Chris Roberts
By Kate Conger
By Brian Rinker
By Rachel Swan
You might say it was a step-by-step process.
First, the consultants decided the contaminants found in the soil of the site need not be considered in their analysis. Geomatrix assumed that most of the worst contaminants had been placed in the ground years or decades ago, and all of the chemicals that would leach from the soil into the ground water had had already done so.
Then, Geomatrix averaged the levels of toxics it found in its underground water testing program. Although there were hot spots, where contaminant levels greatly exceeded state hazardous-waste standards, the averages of the levels at many wells produced results that exceeded the standards by, at most, a factor of 10. The Giants' environmental consultants argued that this level of pollution did not pose a significant environmental threat.
Also, the consulting firm traveled a tortured analytical course to conclude that the contaminants found at Well-Point No. 6 -- the hot-hot spot, where carcinogenic petroleum byproducts abounded in the ground water -- should simply be ignored. Geomatrix concluded that Well-Point 6 was stable, that ground water located there would not move into the bay. Geomatrix supported this conclusion by noting that wells closer to the bay, in the direction of ground-water flow, found none of the pollutants seen in Well-Point 6. Happy with the findings from the relatively unpolluted wells, Geomatrix surmised that the BTEX was bound to coal tar in the soil and wasn't moving.
This argument is not, by any means, universally accepted as true.
Two expert toxicologists say that if BTEX was detected as a separate compound, it had already dissolved out of the coal tar, and would migrate freely. But even if the BTEX was, indeed, chemically connected to the coal tar, it probably would not remain there for long. BTEX, by its very nature, separates from coal tar. "That's what it does," says Chris Shirley, the lead scientist for ARC Ecology, a nonprofit group advocating for the cleanup of local military sites. Stan Smucker, head toxicologist for the federal Environmental Protection Agency's western region, agrees with Shirley's assessment.
Yet, by assuming that the pollution detected in Well 6 wasn't going to migrate, Geomatrix was able to exclude the incredibly high levels of toxics found there from the firm's assessment of the risks to aquatic wildlife posed by underground pollutants on the stadium site.
Moreover, Geomatrix didn't conduct tests that could have turned up evidence damaging to the thesis that underground pollutants could be safely left in place. For example, no test was done to assess the solubility of the chemicals in the soil. That means Geomatrix didn't scientifically ask what is perhaps the key environmental question related to the stadium site: Can chemicals in the soil continue to migrate into the ground water and, by mixing with tidewater, into the bay?
Other study practices have come into question. The firm drilled test wells 120 feet to 240 feet apart -- so far distant that, other environmental experts suggest, the firm most likely missed several hot pollution spots. The ground water under one building on the site was left almost completely untested.
And the firm tested the ground water during just one season -- the summer dry season, when the ground-water table is depressed and may not be reached with the shallow test wells used by Geomatrix. A more thorough study would have tested the water table four times over each season and at far deeper levels.
To test the ground water only once is considered risky if not foolhardy. Lots of toxic contaminants could potentially be missed and any results flowing from the one "snapshot" test are not entirely reliable.
The Regional Water Quality Control Board seemed to bend over backward to accept all of Geomatrix's arguments for leaving polluted soil and ground water in place at the stadium site. The board even added arguments that helped the Giants avoid the cost of cleaning up the site.
And some of that bending and helping does not seem to be supported by science or logic.
For example, board staffers echoed Geomatrix's argument that any leaching of toxics from soil into ground water happened long ago and is no longer occurring. That argument does not seem to have a scientific basis. Asked what studies back his agency's conclusions about leaching of chemicals and movement of water on the stadium site, Vic Pal, the water board's project manager on the Giants stadium, says, "That's our intuition."
And Pal readily admits that the water board doesn't know very much about ground water to surface water migration of toxics. "It's an area we've only recently looked at," he says. "Just since the '90s."
To be fair, while they intuited their way to a Giants-friendly conclusion, water board staffers operated in a near total regulatory vacuum that reflects a lack of scientific study. Most of the levels and standards Geomatrix and the water board used as yardsticks for toxic pollution apply to what are called "point discharges" -- that is, pipes spitting water into a bay or a river, usually from sewage treatment plants. These kinds of discharges are easy to measure and regulate. When you have soil leaching into ground water, which then seeps into surface water -- in the Giants' case, the bay -- measurement and regulation are admittedly difficult.