County utility officials say a comprehensive survey of ground water around the county-operated Millersville Landfill shows that it was not the source of contaminants found in four neighboring wells.
Utilities Director Thomas N. Neel said water from 100 test holes drilled between the landfill and the four contaminated residential wells was tested and found free of contamination.
A battery of tests has determined that ground water in the area is flowing east from the landfill, Mr. Neel said. The four wells found contaminated in April are north of the site, he added.
"This was not a quick, hurry-up job to just clear the county. I said 'Prove to me that it's not leaving the site,' and it's been proven," Mr. Neel said.
He said a second consultant, ERM of Philadelphia, was brought in as a quality control check of the work of the first consultant, Geo Syntec of Atlanta.
He said the county has spent $350,000 for ground water testing, drilling of new wells and mapping the site.
Mr. Neel said it is difficult to say what caused the contamination, but that it could be a dried up well or failed septic tank on a neighboring property.
"It might be tough to ever find out," he said. "It could be as simple as somebody washing their paintbrushes with solvents that could have seeped into the ground water."
Neighbors of the landfill reacted skeptically to the report.
"They still can't prove where the pollution came from, and that's alarming," said John Scofield, chairman of the 13-member Millersville Landfill Citizens Advisory Committee.
Mr. Scofield, who lives a quarter-mile west of the landfill, said the findings raise the question of whether the county is responsible for traces of pollutants found in residential wells near the facility.
He said they also fail to allay fears about future problems from pollutants that county officials acknowledge exist within the landfill property.
"What gets everyone so upset is that it's still a problem and probably always will be. It could leak on to our properties a year from now, five years from now. There's no way of knowing when this stuff might leak out," he said.
The county drilled new wells for the four families with contaminated wells, after County Executive Robert R. Neall vowed April 15 that they would get new wells if the source of the contamination wasn't known within a month.
Mr. Neel said the findings of the ground water surveys mean the Department of Utilities will go no further to find the source of the well pollution.
He said the department will direct its efforts to cleanup work and remediation at the site. It also will continue to monitor ground water and try to gain access to surrounding properties to conduct additional tests, as part of the overall cleanup effort. "It's an ongoing process," he said.