Lines such as NJ Transit comply with Dec. 31 deadline for key safety technology, spending about $11.5 billion, with $3.4 billion in federal grant and loan funds provided.

Safety board faults Sound Transit for failing to have "effective mitigation" for hazardous curve that lacked operating train-control safety system.

Stewards of public transportation and rail systems throughout the U.S. are facing both certain deadlines for installing positive train control (PTC) systems and uncertainty regarding the future of grants due to a proposed budget that has left some projects in limbo.

Freight railroads have positive train control systems on 60% of their route miles, passenger lines lag, at  25%.