Washington County Commissioners President Gregory I. Snook said he was aware of the contamination and the problem is typical of agricultural counties.
Bucher said the contamination is most likely the result of the county's karst terrain, which is prone to cracks, sinkholes and depressions. She said 89 percent of Washington County is made up of karst geology.
As a result, contaminated surface water that can include substances ranging from runoff to animal waste may run into those openings and seep into well water, Bucher said.
Places with contaminated well water include new subdivisions in the areas of White Hall and Beaver Creek roads and in the Smithsburg, Boonsboro and Cearfoss areas, Bucher said.
"Most of the wells are what we call under the influence of surface water," Bucher said.
Bucher said the water contamination problems have been going on for decades.
"This is not a problem that's new," she said. "It's a problem that the Health Department has been dealing with since the sixties. It's always been put on the back burner by the County Commissioners."
Bucher said there were outbreaks of hepatitis in the early 1960s in Washington County and in the early 1980s from contaminated well water.
Richard McIntire, spokesman for the Maryland Department of the Environment, said the state may have to order the county to take steps to help prevent well contamination.
"We've had some concern about the situation and ... wells in Washington County for some time," McIntire said. "Some additional moves may be needed."
McIntire said MDE officials will soon discuss what steps should be taken in the county.
Health officials plan to ask the County Commissioners to mandate that all new wells drilled in karst terrain be treated with water softener and then by ultra violet light and that a filtration system be placed on wells to lessen the chance of people becoming ill, Bucher said.
The ultra violet light system will rid the water of some but not all bacteria, Bucher said. The filtration system will break down the bacteria that gets past the ultra violet light treatment.
The treatment will cost homeowners between $2,000 and $3,000 each, she said.
The Health Department's first option would be to hook up rural homes to public water and sewer systems, but that may be costly, Bucher said.
Bucher said many rural areas in Pennsylvania and West Virginia are hooked up to public water and sewer.
"We're kind of behind the eight ball here," Bucher said.
Snook said residents with wells should make sure they're taking proper precautions to keep their drinking water safe.
"That's fairly typical in any county that has a rural environment with a lot of septic," Snook said. "It's something that we need to keep an eye on, but we're not going to be able to eliminate all the problems."