Part of the No 3 water tunnel scheme that involves excavation of 93 km of deep tunnels. Grow/Perini/Skanska completing final 1,500 m of this 7.9 km x 7.06 m-diameter drive in extremely hard granite and gneiss up to 275 MPa with igneous intrusions and abrasivity in the range 3.3 to 4.3 on the Cherchar abrasivity index. Robbins HP TBM 235-282 giving around 1.8 m/h advance in this rock, but frequent cutter changes distort the overall performance. March 1999.  De Neef reports success by Perini, Grow, Kiewit jv using polyurethane chemical grout injection to stem 200 gpm inflows which trapped TBM. Large diameter holes were drilled and equipped with 1.8 m-long mechanical downhole packers to facilitate stage grouting using Hydro-Active Cut with a high dose of accelerator. More details from www.deneef.com February 2000.Camp Dresser & McKee and Hatch Mott MacDonald jv is providing engineering services for replacement of two existing siphons crossing New York harbour between Staten Island and Brooklyn by 1.9 m-diameter pipeline within 3.8 m-diameter, 3.2 km-long tunnel bored by EPB or slurry TBM. Final design with bids scheduled for mid-2009. Visit www.hatchmott.com/contentpages/pagecontent.aspx and www.cdm.com. 08/09.