The Pennsylvania Department of Environmental Protection is smoothing the way for natural gas drillers to use fluids collected from mining sites in fracking operations.

The agency has set a February 2012 timetable to authorize the repurposing of acid mine drainage for hydraulic fracturing, which department spokesman Kevin Sunday said will divert some of the more than 300 million gallons of mine drainage water that the DEP estimates flows into the state’s rivers and streams each day.

“That’s an incredible amount,” Sunday said. “Instead of that water going into our waterways, a potential solution is for that to go underground — deep, deep underground, thousands of feet below groundwater tables — and be put to use in hydraulic fracturing.”

Because the proposal would substitute acid mine drainage for other water sources currently used in fracking, DEP Secretary Mike Krancer has called it a “win-win” scenario, reducing demand for fresh water while preventing mine drainage from being released directly into surface water.

However, the agency has not yet set rules for how the mining runoff would be handled after being used in fracking. Sunday said that some would likely be re-used for fracking. “There is some treatment involved in that,” Sunday said. “There would also certainly need to be treatment if that water is ever to be discharged back into state waterways.”

It’s also unclear how acid mine drainage would be collected, stored, and transported to drilling sites. Sunday said that the DEP is currently meeting with stakeholders from the energy industry and environmental groups in order to nail down these and other details. The department anticipates that it will release a final position paper in early 2012, Sunday said, with use of mine drainage in fracking expected to commence shortly thereafter.