More residential wells have been contaminated near the Millersville Landfill, and although county officials say the trash facility is the primary suspect, a septic tank could be the source.
Members of the Millersville Landfill Advisory Committee learned Wednesday night that 20 residential wells show at least traces of pollutants similar to those found in ground water beneath the 567-acre dump. Four show levels above federal drinking water standards.
"I'm assuming that it's coming from the landfill, and I've told my engineers that they'll have to prove to me it's not," said Thomas Neel, director of the county Department of Utilities. "Right now, I don't have a comfort level that it's not."
The majority of the contaminated wells are clustered on New Cut Road at the northeastern edge of the landfill. As a result, county efforts to pinpoint the source of the contaminants have been concentrated there.
The county has found a septic tank contaminated at levels 10 times those of the wells in the same area, Neel said.
"We're not blaming anybody. All we know is we've got a hot septic tank," he said.
If the landfill is polluting the wells, Neel said the county is prepared to clean up the site. However, he added, "I can't start any remediation until we define what the problem is and where it is."
County officials also outlined steps being taken to bring the landfill into compliance with environmental laws.
The county has hired a contractor to remove tires dumped at Millersville, said John Zohlen, acting chief of the Solid Waste Bureau. The county pays Joseph Smith and Sons, a Prince George's County recycling firm, $99 per ton to haul tires away,
shred them, separate steel belts, and return the powdered rubber to the landfill.
Utilities spokeswoman Jody Vollmar said the powdered rubber is used to prevent erosion of the working areas of the landfill.
"Instead of just being dumped there, it's being put back for a purpose," she explained yesterday.
Tires are allowed in the landfill if they are shredded or "effectively anchored," something the county has not done since its shredder broke in the early 1980s.
Meanwhile, the county continued to accept tires at the landfill "because we were concerned that if we didn't take them, people would just start dumping them on the side of the road," Vollmar said.
A year and a half ago, the county advertised for a waste hauler who would recycle tires. However, when county budget officers learned the county would have had to pay $100 per ton -- $50 more than it collected in fees when the tires were dumped at the landfill -- that plan was scrapped, too.
The advisory committee also learned Wednesday that the county will hire an inspector to check loads for prohibited trash. Neel said the inspector will randomly monitor commercial haulers' manifests and spot-check trucks for mailing labels and addresses. Only county trash is allowed in the landfill.
Steve Shugart of Geo-Syntec, a firm that is designing new environmentally safe disposal areas at the landfill, said five monitoring wells at the landfill have shown contaminants since the county began testing in 1990.
Contaminants -- primarily toxic chemicals associated with cleaning solvents -- have been found consistently in Well 11 since 1985, when the state was doing the testing. The county has monitored similar pollutants in Well 18 since February 1990.
Since the Health Department found the first residential well polluted two months ago, the county has tested 159 residential wells, said Richard Dixon, regional manager of the county's public water system. Four wells have contaminants above federal drinking water standards and 16 others showed traces, but at levels considered "safe" by the Environmental Protection Agency, he said.
Residents on the advisory committee expressed fears that abuses by previous landfill managers may go undetected and could endanger their health. They fear the landfill's earliest disposal areas were dug much deeper than was approved by the state, skewing the county's attempts to track underground movement of pollutants.
Steve Shugart said the county will attempt to drill through the trash mounds to determine the depth of the trash.
Residents also were upset that the county abandoned a test well that was "highly" contaminated with acetone. Shugart said the county only sampled the well once before a piece of landfill equipment ran over it. A new well was dug within 50 feet, but no contaminants were found, he said.
Utilities officials will update the general public on the landfill at 7 p.m. May 27 and again June 4 at the Odenton Elementary School, Vollmar said.
The Millersville Advisory Committee will meet with Anne Arundel County Health Department officials at 7 p.m. June 3.