Hydraulic fracturing has sparked a two-front battle over Wyoming's water supply, environmentalists say.

First, there is quantity: Fracking sends millions of gallons of water -- a prized commodity in the West's limited water system -- underground to churn up oil and gas. Next, quality: Questions remain about whether chemicals pumped downhole can seep into groundwater.

Though drillers have dismissed such concerns as overblown, researchers at the Powder River Basin Resource Council want state officials to consider measures to ensure groundwater protection.

"This analysis makes it clear that Wyoming must embark on a proactive and thorough program to bring our water management systems up to date," said Bob LeResche, an author of the report. "We need to apply existing statutes to guard, conserve and recycle our groundwater from cradle to grave."

First on the list of recommendations, the environmentalists called on the state to create a "water budget" for major aquifers. State officials would carry out a comprehensive groundwater inventory program, which would estimate the volume of water needed for oil and gas production and determine where that water would be drawn from, based on available water and aquifer recharge rates.

Control zones would be considered for aquifers that have already dipped in recent years. In parts of Campbell, Converse and Johnson counties, for example, groundwater withdrawal has been too quick for replenishment to catch up.

The resource council also recommended a robust effort to analyze, inspect and plan for wastewater from fracking operations. During well fracturing, chemical-laced water mixes with underground particles, eventually resurfacing as a hazardous mix that can include sodium, chloride and arsenic compounds, and naturally occurring radioactive material (EnergyWire, Sept. 6, 2012).

That wastewater is then recycled, treated or blasted back underground in a separate disposal well for permanent storage. The Wyoming group called on the state to begin tracking the transport and disposal of that wastewater and hire more inspectors to check for spills and illegal dumping. It also recommended that the governor appoint a task force to make sure all existing disposal wells are in good condition and project how many additional wells the state can manage.

Rounding out the list of seven recommendations, the environmentalists pushed for a well plugging program that helps to identify abandoned wells, a task force to evaluate waste disposal facilities, and a multiagency analysis of wastewater recycling and reuse.

The group emphasized that the state should work with the oil and gas industry to find solutions to questions of water contamination and availability.

"We should invest in analysis, regulation and perhaps infrastructure that will allow the energy industry to take advantage of profitable new production techniques but also minimize conflicts with Wyoming's continued need for careful stewardship of our scarce groundwater," LeResche said.

Wyoming Gov. Matt Mead (R) believes "protecting water resources is a priority," according to a statement from his office, and is open to considering the Powder River Basin Resource Council's ideas.

"There will almost certainly be several initiatives regarding water in Governor Mead's soon-to-be-released energy strategy," spokesman Renny MacKay said in an email. "That is a fluid strategy that will be continually updated over the coming years and Governor Mead looks forward to hearing more about this report and its recommendations."

John Robitaille, vice president of the Petroleum Association of Wyoming, said the council's recommendations would be redundant because the state already adequately monitors oil and gas producers' water usage and disposal. And oil and gas industry representatives maintain that hydraulic fracturing does not put groundwater at risk because well bores are fractured so far below the water table.

Wyoming is the site of state and federal investigations into groundwater contamination near the Pavillion oil field. An early report from U.S. EPA found some fracking fluids in deep monitoring wells but none in drinking water. Though the investigations are ongoing and the findings have been challenged, the EPA data were enough to rattle some public confidence in fracking (EnergyWire, Dec. 7, 2012).