Traces of gasoline contamination have been found in the water wells at four additional Harford County gasoline stations, the county's health officer told the County Council last night.
The report by Dr. Andrew Bernstein brings to seven the number of gasoline stations identified in Harford as sites of possible contamination by methyl tertiary butyl ether, or MTBE as it is commonly called.
The four stations include a Royal Farms store on Route 22 in Churchville that Bernstein said voluntarily stopped serving food, coffee and sodas from its fountains yesterday. The health officer said contamination problems at the station had been mentioned at a previous public meeting.
He said that MTBE, a potentially carcinogenic gasoline additive, has been a problem at the site for some time and the station had installed a filtration system to eliminate the chemical from the water.
Bernstein said the MTBE level in the raw water at the station was 20.5 parts per billion. This is just slightly above the 20 parts per billion level at which the Maryland Department of the Environment encourages use of a filtration system.
Bernstein told the council that the MTBE level was higher in the water that had passed through the station's filtration system, and expressed suspicion that the system was not being properly maintained.
He said that the water at the Crown station across the road from the Royal Farm store also was contaminated by gasoline, but he could not say that it was MTBE. He said the station closed several weeks ago.
In addition, Bernstein said a 7-Eleven store on Pleasantville Road in Fallston had 26 parts per billion of MTBE in its raw water, but this was reduced to a non-detectable level after passing though a filtration system.
A Citgo station in Jarrettsville had 2.5 parts per billion MTBE in its well. Bernstein said it has not been determined if the station is the source of the contamination.
Councilman Robert G. Cassilly asked Bernstein if neighbors of the new sites had been notified. The health officer said there was no provision in the law for notification of residents, and that they had not been given notice.
"I don't care what the law says," Cassilly replied. "I think the citizens should be notified, even if a letter is sent out."
The Maryland Department of the Environment has previously disclosed MTBE contamination at an Exxon station in Upper Crossroads, near Routes 165 and 152.
MTBE has also been found at Fallston Gas & Go on Route 152, about five miles from the Upper Crossroads Exxon, while a 7-Eleven in Aberdeen is suspected of leaking MTBE into a well that serves the city's public water supply.
Bernstein said there are 83 gasoline stations in the county, the vast majority of them on public water systems. He said the department's priority was to first test stations that use wells for their water supply.