Nationwide Differential Global Positioning System

The Federal Highway Administration (FHWA), cooperating with the U.S. Coast Guard, Federal Railroad Administration, and Office of the Secretary of Transportation, proposed to select, install, and operate a Nationwide Differential Global Positioning System (NDGPS) to augment existing satellite-based GPS range information from a network of ground-based reference stations transmitting from known positions throughout the United States. SRI researched and prepared a programmatic environmental assessment (PEA) using lead and cooperating agency guidelines for implementing the National Environmental Policy Act. This PEA provided support for a finding of no significant impact (FONSI) provided that site-specific analyses were undertaken under prescribed circumstances. The Final PEA was submitted to the FHWA in September of 1999.