Construction of a 2 ft diameter borehole using Horizontal Directional Drilling (HDD) for Amtrak Railroad to carry a new 300 ft long powerline. The Contractor, Aaron Enterprises, installed pipes for AMTRAK crossing Route 1 & 9 and railroad tracks, using HDD techniques.
Review of soil borings and HDD alignments were conducted and input was provided regarding HDD techniques. The borings showed that HDD would pass through sandy and gravelly soils.
That type of ground is always a challenge in employing HDD technique. Fracking was an issue being that HDD was to be performed close to the ground surface. Design group evaluated the fracking potential and determined the required depth of cover for the HDD pipes. The railroads had warned the contractor that they would not allow seepage of slurry seeping into track ballast. Also, the railroads were concerned with the undermining of tracks by loss of ground during boring. Design Group prepared the methodology for the contractor and the railroads agreed with the analysis and permitted the contractor to proceed with construction. During construction, Designers monitored instrumentation at around tracks to ensure that AREMA