Two engineering and construction firms have won up to $4.7 billion in federal infrastructure funding to build the Frederick Douglass Tunnel in Baltimore. Amtrak said Tuesday that Kiewit Corp. and J.F. Shea Construction Inc. have been awarded a joint contract to build the new rail tunnel for Amtrak and MARC commuter trains that will replace the 150-year-old Baltimore and Potomac Tunnel. “We are ...