The Gay and Neel, Inc. Survey Department has been an integral part of this project since 2008, providing structural monitoring surveys of both the tunnel interiors and surface above, clearance verification, as-built surveys, and general construction surveying support for Johnson Western Constructors of San Leandro, California, the prime contractor to Norfolk Southern for 10 of the Heartland Corridor tunnels.

This was a part of the Norfolk Southern Railroad's "Heartland Corridor Project" to enlarge railway tunnels between Walton, Virginia and Columbus, Ohio to allow double stacked container train transport of freight. Project specifics required precision placement of optical target arrays, daily multiple readings of roof-mounted target arrays for displacements of 0.016' or greater, provision of daily monitoring reports in spreadsheet form and progress drawings of tunnel cross sections, ties to survey control placed on site by others, and calculations of liner clearances relative to proposed track re-alignment. The 10 tunnels range from 800' to over 3000' in length.