The Pennsylvania Public Utility Commission is holding a special hearing as part of efforts to clarify and possibly expand its role in regulating burgeoning Marcellus shale gas well and gas pipeline development.

The hearing by the commission on April 22 in Harrisburg is expected to examine a host of safety issues, including whether the PUC has jurisdiction over the pipelines that will transport gas pulled from the 5,000- to 8,000-foot-deep shale layer beneath three-quarters of the state.

Tyrone Christy, PUC vice chairman, said development of the state's shale gas field or "play," thought to hold as much as 363 trillion cubic feet of natural gas, raised numerous issues about the commission's core regulatory functions and scope.

"We believe that these issues need to be examined and these questions answered sooner rather than later so that we can fully protect the public while not stifling economic growth," Mr. Christy said in a hearing notice last week.

Jennifer Kocher, PUC spokeswoman, said the PUC has regulatory jurisdiction over "public utility pipelines," defined as pipelines transporting gas or oil within the state for compensation.

"But if a drilling company uses its own pipelines to transport the gas it produces, then there's a question about our jurisdiction," Ms. Kocher said. "We're looking at that issue, at our safety jurisdiction, safety issues and the role of the PUC."

Matt Benson, a spokesman for the Pennsylvania Oil and Gas Association, said the industry trade group hasn't addressed the pipeline regulation issue and is taking a "wait and see position" on PUC regulation. He said the group, along with gas producers, hopes to be offered an opportunity to testify at the hearing.

Ms. Kocher said the PUC hasn't had any reports of gas line explosions, but the commission is examining the issue because of the rush of gas development. Estimates are that the Marcellus shale in Pennsylvania and parts of New York, Ohio, Maryland and West Virginia could hold enough gas to supply the nation's demands for 15 years.

State Department of Environmental Protection regulators say 5,000 new Marcellus shale wells could be permitted this year in Pennsylvania, double the number permitted in the state over the last two years.

"There's an enormous amount of development going on and a big increase in the amount of pipelines," Ms. Kocher said. "Our concern is the safety of those lines and who will oversee it. That's unclear right now."

State legislation would be needed to authorize any expansion of the PUC's regulatory role.

On a related Marcellus shale regulatory matter, the PUC increased its transportation enforcement activities in five northeastern counties last month after receiving complaints that well drilling and tanker trucks were operating without PUC certification.

"We've increased enforcement all over the state," said Ms. Kocher.

Roadside truck inspections, in partnership with the State Police, have occurred in Bradford, Sullivan, Susquehanna, Tioga and Wyoming counties. Trucking companies must have PUC certificates and proof of insurance if transporting commodities such as sand, water or stone related to the well-drilling operations.

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