SEPTA hopes the installation will be completed by the end of 2015, as mandated by Congress. But, officials noted, the cost of PTC could mean a delay in other transit improvements. SEPTA Assistant General Manager and Chief Engineer Jeffrey Knueppel said the agency hopes Congres will extend the PTC deadline. "It's recognized nationally as a very aggressive date to hit," he said.

SEPTA also has awarded a separate $1.7 million contract for related right-of-way work to Douglassville, Pa.-based Independence Constructors Corp.

SEPTA's capital budget already is financially stressed, having borrowed $427 million last year to help pay for 120 new Silverliner V cars being manufactured by Rotem. More than half of the Silverliner V cars have been delivered.