The discovery of pollutants oozing from the sides of the Millersville Landfill has prompted county officials to test streams, ponds and other surface water around the 567-acre site.
Solvents and other toxic chemicals commonly associated with household and commercial trash have been identified seeping from at least two mounds at the center of the Burns Crossing Road facility.
However, no contaminants have been found flowing off the site, said Steve Witt, the county's environmental health officer.
On April 28, the county Health Department tested a "goat pond," a drainage ditch and stream between the 8300 and 8500 blocks of New Cut Road. It also sampled Wells Branch and a smaller stream in the 100 block of Gambrills Road. No trace of the volatile organic chemicals were found, he said.
The discovery of toxic chemicals seeping out of the sides of the trash disposal cells is a concern, said Jody Vollmar, a spokeswoman for the county Department of Utilities. But, she added, it was not unexpected.
"It doesn't do anything but confirm what we already knew: that there are contaminants in the landfill," Vollmar said.
The county first found solvents in two ground water monitoring wells in 1985. During the past month, health officials have found similar contaminants at levels exceeding federal drinking water standards in four residential wells along New Cut and Gambrills roads. Traces of pollutants have been found in 11 other residential wells.
At least five "seeps" were discovered around the surface of the landfill and tested during the last month, Vollmar said. Among the chemicals found, only benzene exceeded drinking water standards.
The seeps are caused as rain filters through the ground and trash, which includes discarded cleansers, pesticides and other household chemicals. State Department of the Environment records show that state inspectors have routinely asked the county to seal similar breakouts with clay since the landfill opened 18 years ago.
County officials say they hope to solve the problem permanently by placing an impermeable cap over the trash that prevents rain water from filtering down. They also told the Millersville Landfill Advisory Committee Wednesday night that they hope to be dumping all new trash in a lined cell by the end of November.
Committee members suggested the county also provide residents with public water or filtration devices for their wells.
Several members prodded the county to close the landfill immediately.
"We around the landfill are concerned about ourselves," said Ray Burkhardt, a New Cut Road resident. "Selfishly, I don't want a landfill in my backyard anymore.
But Sam Minnitte, an aide to County Executive Robert R. Neall, said, "Whether it's 25 years or 55 years, we are going to try to maximize the use of this landfill."
The advisory committee is scheduled to meet again at 7 p.m. May 20 in the Patuxent Water Reclamation Facility in Crofton.