DEP's action comes as the U.S. Environmental Protection Agency and activists step up pressure on Gov. Corbett to increase regulation of the shale-gas boom, including the massive volumes of toxic wastewater produced by the hydraulic fracturing process.
"Amidst growing concern by the public and increased scrutiny by the media, we are happy to see DEP finally take these critical steps to once and for all stop dangerous, undertreated Marcellus Shale wastewater from entering our waterways and drinking water supplies," said Erika Staaf, a spokeswoman for the PennEnvironment advocacy group.
DEP's announcement came the day after Corbett, who has been criticized for his close ties to drillers and his refusal to support a gas production tax, assured local officials he would not allow the industry to "poison the water."
"We need to protect the water," the governor, a Republican, told a meeting of the Pennsylvania State Association of Township Supervisors. "But we must do it based on science, not emotion."
The Marcellus Shale Coalition, an industry trade group, said it welcomed DEP's announcement.
Kathryn Z. Klaber, the coalition's president, said the industry is already recycling much of its wastewater and drilling operators are "very confident they can in fact meet these additional limits."
Klaber said the DEP's action was "timely" and that it was a "perfectly reasonable assumption" that the state would eventually put its voluntary order into enforceable regulations.
The DEP and the industry appear to have been influenced by complaints from public water suppliers in Western Pennsylvania that say they are challenged by bromide levels whose concentrations have increased concurrently with the drilling boom.
The bromides themselves are not a public health risk - they account for a tiny part of the salty dissolved solids that create an unpleasant taste in water at elevated levels.
