First Tunnel Boring Machine launches at East Side Access project in Long Island City, Queens

2011-05-20

On Wednesday, May 18, 2011 the first tunnel boring machine (TBM) commenced drilling for the Yard Lead Tunnel on East Side Access Contract CQ031, as part of the MTA Capital Construction project to connect the Long Island Railroad (LIRR) to Grand Central Station. The Yard Lead Tunnel is the first and longest of four tunnels planned for installation beneath the Long Island Railroad and Amtrak train yards, and begins by cutting through around 300 feet of bedrock before transitioning to soils. The TBMs maintain a pressurized grout layer at the cutting heads to minimize disturbance to the subsurface, and create the tunnel walls by pushing pre-cast concrete rings in place behind the cutting head as the tunnel advances. Impact Environmental is responsible for characterization, off-site transportation, and beneficial reuse of the hundreds of thousands of cubic yards of drill cuttings from the tunnel operations.