New wells drilled into bedrock under the county landfill in Marriottsville have found more solvent-contaminated ground water, a newly formed citizens' committee was told yesterday.
The suspected carcinogens, commonly used in grease-cutting, dry cleaning and paint removal, were found in smaller quantities than were discovered a year ago at the first bedrock test well at the Alpha Ridge Landfill.
Semiannual tests at residential wells near the landfill by the county Health Department have not produced contaminated water.
"I would certainly say that deep-water contamination is worse than we thought it was before," said Dr. Donald L. Gill, a University of Maryland Medical School biochemist who lives near the landfill.
He said the results showed that there are contaminants showing up in wells on two sides of the perimeter of the landfill's original, clay-lined cell. The cell opened 13 years ago and was closed last February in response to residents' concerns about the leaking toxins.
Dr. Gill and Marriottsville resident L. Scott Muller have led efforts to bring public water to the area in the wake of the bedrock test results. Both were named to the 10-member Alpha Ridge Landfill Advisory Committee that met for the first time yesterday with Gail Bates, administrative assistant to County Executive Charles Ecker.
What the new test results mean and how they should be characterized in a future edition of a monthly landfill newsletter were the committee's first topics of discussion.
Mr. Muller said he objected to a sentence in a draft of the newsletter saying, "We are cautiously optimistic about the results of the recent tests."
"How could you be cautiously optimistic about levels that are well above EPA limits?" Mr. Muller asked.
Ms. Bates said the language would be removed before the publication was printed and distributed to 550 homes around the landfill that get water from deep wells.
Consultants hired by the county Public Works Department to study the landfill contamination are expected to complete a report recommending measures to correct the problem late this month or in early October, said department Director James Irvin.
The consultants, from Virginia-based GeoTrans Inc., supervised the drilling of 14 bedrock wells this spring and summer. Of those, two between the old and new landfill cells and one on the western edge of the landfill property turned up ground water contaminated with toxic solvents.
The highest levels were found in a well between the two cells. Samples showed 100 parts per billion of methylene chloride, a chemical used for stripping paint. The EPA standard for the chemical in drinking water is 5 parts per billion or less.
The same well turned up 5.1 parts per billion of trichloroethene, just above the chemical's 5 parts-per-billion standard.
Thirteen other compounds that were discovered in the well were either below the EPA standard or have had no standard established.
In the two other wells, five and seven compounds, respectively, were found either below EPA standards or without standards.
GeoTrans is also studying landfill contamination at two closed county landfills, one on Carrs Mill Road in Woodbine, and the other on New Cut Road in Ellicott City. Both landfills are unlined and show contaminated ground water.
Contamination at the Marriottsville landfill first appeared in 1990 in shallow wells north and west of the original cell.
For several years, county officials told Marriottsville residents that bedrock below the landfill would be a barrier against ground water contamination. That belief was shattered with last year's test results.