The US Environmental Protection Agency (EPA) had been investigating allegations that Cabot Oil & Gas may have contaminated some water wells in the area while drilling into the Marcellus Shale play there.
However, the agency sampled 64 wells in the area and did not find drilling-related contamination at levels that would be harmful to human health, the EPA said today as it released its final findings.
“Our goal was to provide the Dimock community with complete and reliable information about the presence of contaminants in their drinking water and to determine whether further action was warranted to protect public health,” EPA regional administrator Shawn Garvin said.
“The sampling and an evaluation of the particular circumstances at each home did not indicate levels of contaminants that would give EPA reason to take further action.”
The testing did find contaminants in some wells such as arsenic, barium and manganese at five wells but those were determined to be naturally occurring and not the result of drilling.
The EPA had been providing alternative water sources to four homes where it feared possible water contamination but testing revealed that those wells did not have levels of contamination “that could present a health concern”, the agency said, and it plans to stop providing water to those homes.
The agency has no further plans for water testing in the area.
Dimock has been one of the focal points for environmental groups that claim fracturing contaminates drinking water.
Some residents there claim their water gained a strange odour, taste and colour after drilling began nearby and have complained of health problems.
They have been locked in a battle with Cabot and state regulators over whether their water is actually contaminated and who is responsible.
The EPA’s decision to wade into the dispute by providing alternative water to some residents and testing wells in Dimock has been a sore point for industry as it pressed for fracking to remain regulated at the state, rather than the national, level.