"It appears unlikely that PTC would be implemented by more than a small number of railroads by the deadline," Susan Fleming, director of physical infrastructure issues for the Government Accountability Office (GAO), told the Senate Commerce, Science and Transportation subcommittee on Competitiveness, Innovation and Export Promotion on Wednesday.
The delays are due to holdups in developing some components, limited federal resources and problems obtaining radio frequency spectrum from the Federal Communications Commission needed to transmit information between elements of the control system.
Federal railroad officials defended the safety controls, saying they will prevent train crashes.
"We know that there will be more accidents that could have been prevented — we're investigating accidents right now that could have been prevented by PTC," said Deborah Hersman, chairwoman of the National Transportation Safety Board. "PTC prevents the most catastrophic accidents."
Joseph Szabo, administrator of the Federal Railroad Administration (FRA), added that it could have a "game changer impact" on rail safety.
The system is expected to cost railroads between $9 billion and $13 billion, but could reach as high as $22.5 billion, according to a 2010 report from the GAO.
Republicans on the subcommittee questioned whether that money couldn't be better spent on other measures.
"I think it's important that we, as Congress, be careful not to impose undue regulation on the railroad industry, especially if these regulations force the railroads to spend money that might otherwise be used for needed infrastructure improvements," said Sen. John Thune (R-S.D.).
Thune, the top Republican on the full committee, said he would soon introduce a bill to extend the implementation deadline.
Sen. Ron Johnson (R-Wis.) added: "I'm always concerned about unintended consequences, and the unintended consequence I'm concerned about here is money spent on PTC not being a very good bang for the buck, relatively." a
In light of the expected delays for the system, the FRA is considering granting extensions to the 2015 deadline on a case-by-case basis.
"It shouldn't be a blanket extension," said Szabo. "We really have to find this appropriate balance between keeping feet to the fire or expeditious implementation, while also making sure that we allow an appropriate amount of time to make sure it's done safely and reliably."
Sen. Claire McCaskill (D-Mo.) worried that that approach would lead to a "piecemeal" implementation and complex bureaucracy.
"I'm not sure if a case-by-case basis is music to the ears of anybody who's regulated by the federal government," she said.
Focus on the train controls has distracted the FRA from other rules and guidelines mandated by the 2008 law.
Of the 17 rules set to be finalized, nine remain outstanding, as do three compliance manuals, delays that Szabo attributed to a lack of resources at his agency.
In addition to mandating reports and regulations, the Rail Safety Improvement Act "also promised us 200 more individuals, and ultimately we were only allowed to hire 31 of those 200," Szabo said. As a result, "we had to prioritize and try to work through them in a systematic order," which focused attention on the train control system.
In recent weeks, trains have crashed in Maryland, Connecticut and Missouri, though rail officials maintain that 2012 was the safest year on record.
"We know that rail safety is improving but these incidents certainly challenge the public's confidence and trust in the system and the credibility of claims that rail safety is in fact improving," said Sen. Richard Blumenthal (D-Conn.), chairman of the subcommittee.