A Pennsylvania lawmaker is taking aim at one of the most contentious issues in the Marcellus Shale: gas migration.

State Rep. Ron Miller, a Republican from York County, recently introduced House Bill 1855, legislation that would require the Environmental Quality Board (EQB) to regulate private water wells. The EQB would set standards for building and abandoning private water wells, and create a licensing and certification program for water well drillers.

“We’ve had some issues in the Marcellus Shale area of the state that are driven by the fact that we have some gas that’s leaking into domestic water wells. The problem is: that’s not necessarily associated with the Marcellus Shale drilling,” Miller said after a hearing on the bill Tuesday. “That has occurred for many, many years in those areas.”

Miller pointed to contamination from naturally occurring methane and conventional shallow gas wells. “The point is that water wells have not been constructed properly to preclude migration of contaminants into them,” he said.

Since the release of Gasland in 2010, the flaming spigot has become the go-to image for critics of the natural gas industry, and shale development in particular, but regulators point to migration cases before shale drilling began.

With more than 3 million residents — Miller among them — relying on nearly 1 million private wells, and around 20,000 new wells drilled each year, Pennsylvania is second only to Michigan in terms of private water well use. But Pennsylvania is one of only a few states that still doesn’t certify water well drillers or require water wells to meet certain standards, according to a 2009 report from the Center for Rural Pennsylvania (CRP), a legislative agency.

That report found widespread contamination of private water supplies. Around half of the homeowners surveyed had never tested their water, and of the 701 wells tested over a two-year period, 41% failed to meet at least one health-based drinking standard. For that reason, the CRP concluded, “Regulations are warranted to increase mandatory testing of private water wells at the completion of new well construction and before finalization of any real estate transaction.”

The issue is a perennially touchy subject. The most recent attempt to set standards, in 2001, failed because rural homeowners worried that regulation would ultimately require them to pay for water from their private wells. Hoping to get out in front of the issue, Miller noted existing laws that prohibit the state from metering private water wells.

While the issue is the same, the circumstances have changed. That’s largely due to the shale boom in the state.

When the independent Statewide Water Resources Committee drafted its five-year State Water Plan in late 2008, it listed certification for water well drillers and water well construction standards as its top legislative priority. And in July 2011 the Marcellus Shale Advisory Commission recommended that the state enact private water well construction standards to prevent contamination from both bacteria and naturally occurring shallow methane.

The potential link between gas drilling and water well contamination divides regulators, academics and the industry.

For instance, the Pennsylvania Department of Environmental Protection (DEP) believes Cabot Oil & Gas Corp. contaminated water wells in Dimock Township, a charge the company denies (see Shale Daily, Dec. 17, 2010), and is investigating whether Cabot contaminated water wells in nearby Lenox Township (see Shale Daily, Jan. 11).

But the DEP harshly criticized a Duke University study showing correlations between hydraulic fracturing and methane contamination in the same area, calling it “biased science” (see Shale Daily, Aug. 10, 2011; June 8, 2011).

And that Duke study doesn’t jive with a 2011 CRP study of 233 water wells across Marcellus country that found 20% to already be contaminated by methane before drilling began nearby (see Shale Daily, Dec. 1, 2011; Oct. 28, 2011).

For that reason, the industry is in favor of standardization. “Through pre-drill testing of water wells in areas of development, the natural gas industry is actively addressing long-standing public health challenges from these water wells,” Marcellus Shale Coalition President Kathryn Klaber said. “This testing, conducted by state-certified laboratories and funded by the industry, is in a scale never witnessed before in the Commonwealth’s history. As such, the natural gas industry believes collaborative and comprehensive public policy solutions should be the next appropriate step to ensure that those who use private water wells can be assured that they have clean and safe drinking water.”