A chemical leak at the site of a Marcellus shale well at Beaver Run Reservoir did not make its way into Westmoreland County's drinking water supply, officials said.
Liquid cement - which includes bentonite, a chemical found in clay that also is used in cat litter - leaked into a creek that empties into reservoir at the Kuhns 3B well pad in Bell Township on July 21 at 10:30 p.m.
The driller, Consol Energy's CNX Gas, was cited by the state Department of Environmental Protection for "discharge of pollutional material to waters of the Commonwealth."
Workers were pouring a bentonite and concrete mix to encase a well opening when they realized they had bored through an underground stream that would carry the mixture to the reservoir, said John Poister, spokesman for the state Department of Environmental Protection. The next morning, drillers found the mixture in the stream and began to clean it up, he said.
The company was in compliance with the department's spill policy, Poister said, and an inspection was conducted July 22. A state water-quality specialist conducted a follow-up inspection July 23. Consol had stationed a pump truck to stop run-off from entering the stream and the reservoir downhill from the discharge spring. The company also hired an environmental cleanup firm to help with water sampling and monitoring, Poister said.
"At the time of inspecting, the department notes that the site appeared to be in sound condition with no sign of accelerated erosion and sedimentation in relation to the access road or well pad area," Poister wrote in an email.
The spill contained 80 barrels of fresh water, 40 barrels of bentonite clay and 20 barrels of type-one cement, Poister said.
A July 31 inspection showed that the stream has been restored and flushed by recent rainfall.
"What the public needs to know is that we're not worried about the water quality now," Consol spokeswoman Lynn Seay said, calling the substance harmless.
Officials said they do not know how much bentonite and concrete got into the reservoir. Neither is a toxic substance, Poister said.
Beaver Run Reservoir serves 150,000 customers in Westmoreland County, including those in Murrysville, Export and Delmont.
Trib Total Media staff writer Timothy Puko contributed to this report.
