By Alan Prendergast
By Michael Roberts
By Michael Roberts
By Amber Taufen
By Patricia Calhoun
By William Breathes
By Michael Roberts
By Melanie Asmar
From time to time, Assistant City Attorney Sullivan reported to his colleagues what Anderson was saying at various public forums. In an October 19, 1999, memo, he wrote: "Having been unsuccessful by alleging significant plutonium contamination at Lowry, Adrienne Anderson has broadened her alleged concerns to include all radionuclides. At least this appeared to be the thrust of her testimony at the [EPA] ombudsman's hearing on Saturday. It may be wise to hire a radiation expert separate from Parsons to ensure we have the best analysis available to answer any questions that may be raised. Ms. Anderson has made the Lowry site her pet project, and she will continue to raise new questions unless we can respond authoritatively. You may recall that she started by alleging Section 6 was the site of Army chemical weapons training or storage during World War II (she had the wrong section and probably the wrong operation), then she alleged plutonium contamination (no evidence), and now she is alleging shipment of radium and depleted uranium waste by Shattuck."
Rather than do the "best analysis available," however, Lowry officials didn't even bother to resample any of the wells that had turned up hot. A database maintained by the City of Denver shows that with the exception of one shallow well, no sampling whatsoever was done for plutonium or americium during a seven-year stretch, from roughly 1991 to 1998. "It wasn't required by the EPA," explains Dennis Bollmann, who supervises the city's activities at the landfill.
During this period, workers were quietly plugging dozens of monitoring wells, including many that had registered high readings for plutonium and americium, records show. Federal and city officials say the wells were plugged to ensure the integrity of the landfill cap and to increase the efficiency of a gas-extraction system. But the plugging also prevented any additional sampling in those disputed wells.
According to Bollmann, the plugged wells had been drilled years earlier in order to better ascertain the nature of the contaminants present in the landfill. Once the EPA's Record of Decision was issued in 1994, the goals changed, and sampling was performed to determine "whether the site was in compliance with the regulations," he says.
As for the four aquifers that lie beneath the site -- the Dawson, the Denver, the Arapahoe and the Laramie-Fox Hills -- Bollmann says they haven't been contaminated. "We have samples from the lignite bed, located on top of the Denver formation, that are clean," he says. "We have samples from the upper Denver aquifer that are clean. And with a few scattered exceptions, the samples in the unweathered Dawson are clean."
Although water samples taken from wells drilled deeper than 300 feet contain numerous chemicals, including solvents and heavy metals, those solvents are most likely the result of contamination from the labs doing the analyses, Bollmann says. The metals, he adds, are not present in levels exceeding "background concentrations."
And what, exactly, are the "background concentrations" at Lowry? At the landfill, contamination is defined as the "presence of a chemical above background concentrations." But the wells that have been designated as "background" wells are not free of pollutants, either.
Many of these "background wells" are located south of Quincy Road -- one of the areas where patrolman Bill Wilson saw tankers dumping their loads decades ago. According to the city's database, these wells also contain numerous chemicals and radionuclides -- but since they are "upgradient," or upstream of the landfill, the EPA has allowed them be used as background wells. The result? The contamination that is present in the on-site wells is downplayed.
One of the deepest wells, dubbed WW-40, descends more than a thousand feet to the Arapahoe Aquifer; it's located near the Gun Club Road entrance to the landfill. According to both Bollmann and the EPA, no contaminants were found in this well. But the database tells a different story: Arsenic, lead and mercury were among the chemicals detected when WW-40 was sampled in 1993 and again in 1994. Apparently no testing was done for radionuclides or volatile organic chemicals, which are extremely prevalent at the site. And despite the well's clean bill of health, landfill workers are drinking "commercially bottled drinking water," EPA records show.
Several other deep wells -- GW-116, GW-117 and GW-118 -- were drilled near the center of the landfill, but the database contains no sampling results for these wells. According to Bollmann, the wells were drilled not to test for contaminants, but to determine whether a fracture existed below the landfill. No such fracture was found, he says.
In 1998, landfill officials finally began testing wells again for plutonium contamination again -- but these samples were mostly taken from newly drilled wells located just outside an underground barrier wall. Even so, the database shows that these wells, which are all relatively shallow, contain plutonium and americium, albeit in low amounts.
The database reveals other puzzling trends. For example, there are 436 results in the database showing plutonium and americium levels ranging from a few hundredths of a picocurie to hundreds of picocuries. But 278 results, including nearly all of the highest readings, are dismissed as "undetected" and marked with a "U" in an adjoining column. When asked about the notation, Gwen Hooten, the EPA's current project manager at Lowry, says it represents the "detection limits" of the laboratory doing the analysis and not the actual concentration.