U.S. Sen. Bob Casey, D-Pa., in a letter to the U.S. Department of Transportation's Pipeline and Hazardous Materials Safety Administration raised concerns about the safety record for pipelines and gas extraction in his state.
Marcellus Shale gas deposits locked in the Appalachian Basin yielded 100 million cubic feet of natural gas in 2009. Environmental groups worry the process that releases gas from shale deposits causes irreparable damage to the environment, however.
In terms of gas pipelines, Casey's office said there are 7,500 miles of interstate gas pipelines and 63,000 miles of intrastate pipelines running across his state.
"It is critical that sufficient resources are dedicated to caring for the entire pipeline transportation system," Casey wrote in his letter.
The U.S. Transportation Department in response to mounting concerns over regulation and safety said it proposed raising the penalty for serious pipeline violations from $1 million to $2.5 million.
Additional recommendations include expanding safety requirements to cover entire pipelines and tighter control over personnel conducting maintenance on oil and gas networks.