The old crossing and railroad track was completely dismantled and native soil under the crossing was removed to a total depth of 27 inches.  A geotextile fabric was placed to prevent mud from contaminating the new crossing sub-base.  A new sub-base of crushed rock was placed 4 to 6 inches at a time.

Each layer of crushed rock was compacted using a vibratory roller.  A final layer ("lift") of very small crushed material was placed to achieve a smooth and uniform surface for the new pre-cast crossing surface.