CHARLESTON, W.Va. -- Federal lawmakers will examine pipeline safety issues again this year, this time in Charleston at a field hearing scheduled in the wake of last month's near-disastrous explosion of a NiSource natural gas transmission line near Sissonville.Senate Commerce Chairman Jay Rockefeller, D-W.Va., announced that his committee would hold a field hearing, "Pipeline Safety: An On-the-Ground Look at Safeguarding the Public," on Jan. 28."The Sissonville explosion shook West Virginia quite literally, and served as a stark reminder that pipeline safety is serious. And oversight is critically important," Rockefeller said in a prepared statement issued Monday.The Dec. 11 explosion occurred when a 20-inch diameter interstate transmission line north of Charleston ruptured, exploded and set a wall of fire over Interstate 77. Several people received minor injuries, several homes were destroyed, and the ensuing fire engulfed and damaged a large section of I-77.The field hearing will give lawmakers a chance to discuss two key pipeline safety reports due out over the next few weeksInvestigators from the National Transportation Safety Board are scheduled later this week to issue their preliminary report on the NiSource explosion in Sissonville. And the U.S. Government Accountability Office, or GAO, is set to issue a study about the ability of pipeline operators to respond to hazardous liquid or gas releases Jan. 23.Rockefeller said the hearing would also be used as an opportunity to review the Department of Transportation's implementation of the Pipeline Safety, Regulatory Certainty and Job Creation Act of 2011, which was modeled in part on legislation co-sponsored by Rockefeller."Passing comprehensive pipeline safety legislation was a good step, but I did push for even stronger provisions in that bill -- and we must assess where implementation of that law stands, and whether future actions are needed," Rockefeller said.At least two key NTSB recommendations not included in the latest legislation would improve the way pipeline operators check the integrity of their pipes.One recommendation is to eliminate a "grandfather" provision that exempts older pipelines from the requirement for hydrostatic testing. Such testing is time-consuming and expensive because pipelines must be taken out of service for the tests.The other would require all pipelines to be built so they could be tested by so-called "internal line inspections," using devices with built-in cameras and sensors. Changes in pipe diameter and sharp turns and curves can make this testing difficult. Only about 70 percent of the nation's pipelines are currently suitable, officials said.A third NTSB recommendation not included in the legislation would have required more frequent use of automatic or remote shutoff valves, technology that could have reduced the amount of gas that fueled the fire if it had been in place on the Sissonville line.Among other things, the GAO study is to focus on risks and benefits of automatic and remote shutoff valves, the swiftness of leak detection and pipeline shutdown capabilities, and the location of the nearest response personnel.Under Rockefeller's leadership, the Senate committee held three hearings in 2010 and 2011 that focused on pipeline safety. Pipeline safety was mentioned, but was not a major issue, during a previous field hearing Rockefeller convened last year in Fairmont to discuss development of natural gas from the Marcellus Shale.Reach Ken Ward Jr. at firstname.lastname@example.org or 304-348-1702.