CANTON, Pa. — Workers stopped the flow of liquid and natural gas from a well that spilled chemical-laced water for two days and were to start procedures to seal the well Friday, company officials said.
Chesapeake Energy Corp., which was drilling the Marcellus Shale well near Canton in Bradford County, said the liquid leak was stopped Thursday afternoon.
Following an equipment failure Tuesday night, a small amount of gas and thousands of gallons of liquid spilled from the well, crossing farm fields and entering a stream. The exact cause of the blowout remained unclear, although Chesapeake spokesman Brian Grove said Thursday it took place in a wellhead connection.
Houston-based well-control specialists pumped ground-up tires, plastic bits and other rubber material into the well to plug the leak. They were to pump heavy mud into the hole to kill the well and replace the malfunctioning wellhead.
State environmental regulators and nearby residents were still waiting on results from tests to determine the extent of contamination of nearby waterways and private water wells. Results of tests on water samples taken by the state Department of Environmental Protection were expected next week, but an agency spokesman said field checks found no cause for concern.
Brad Hugo, a welder who lives down the road from the well site, told the Pittsburgh Post-Gazette that his family had found no sign of contamination in their well water, but they decided to drink bottled water anyway.
Oklahoma City-based Chesapeake Energy officials say the environmental impact is minimal.
The company nonetheless froze all post-drilling work on its wells in Pennsylvania, West Virginia and Ohio while it investigates the reason for the blowout.
Officials from the U.S. Environmental Protection Agency, the Occupational Safety and Health Administration and the Pennsylvania Fish and Boat Commission were on the scene.
Drilling a Marcellus Shale well involves pumping millions of gallons of water and sand laced with chemicals down the well bore at high pressure to break up the dense shale rock more than a mile beneath the surface and release the gas trapped inside. The process is known as hydraulic fracturing.
Some of that chemical-laced water returns to the surface as a briny stew carrying sulfates, chlorides, metals and naturally occurring radioactivity that the wastewater picks up deep underground.
DEP spokesman Dan Spadoni said the agency has taken water samples from Towanda Creek and a tributary to screen for chlorides, sulfates, arsenic, barium, iron, magnesium and strontium. The DEP also took samples from seven nearby private wells and from the Susquehanna River where Towanda Creek empties into it, about 16 miles from the well pad, he said.