Parsons Brinckerhoff has been named construction manager for two interceptor tunnels being built on the Sacramento River by Affholder. PB is responsible for providing complete construction management services, including contract administration, quality assurance, schedule, cost control, inspection, construction staking, and materials testing for the County of Sacramento. Visit www.pbworld.comThe USD44 million tunnels are part of the lower northwest interceptor project being undertaken by the Sacramento Regional County Sanitation District in Sacramento. The project consists of two bored tunnels of approximately 4.6 m excavated diameter. The Northern Sacramento River Crossing is 598 m-long while the Southern Sacramento River Crossing (SSRC) is 631 m-long. The tunnels will be inclined downwards at 6% from deep shafts on either side of the river. The geology consists of alluvial sand, silt and silty sand associated with recent Sacramento River channel deposits, overlain outside the river levees by clayey soils representing river flood deposits. Two Lovat EPB TBMs will be used, equipped with a screw conveyor at the bottom of the cutter head. Method of muck transport on 6% grade as yet not defined. Lining with gasketed, precast concrete segmental linings installed behind the TBMs, while the twin steel carrier pipes will be installed inside the excavated tunnels and shafts, and the tunnels backfilled with low density cellular concrete. Other underground structures at the NSRC include a 10.6 m-wide x 45.4 m-long x 8.5 m-deep launching shaft and a 7.6 m-wide x 15.2 m-long x 14.8 m-deep receiving shaft. At the SSRC, a 10.6 m-wide x 45.4 m-long x 8.8 m-deep launching shaft and a 7.6 m-wide x 15.2 m-long x 8.8 m-deep receiving shaft. Notice to proceed for work start on 23rd July, 2004 with expected end in September 2006. Visit www.lowernorthwest.com and www.lovat.com 29/04.A USD19.3 million construction contract was awarded to Affholder on 13th October, 2004 for construction of a 2,379 m 1.83 m-diameter gravity pipeline, a project known as Bradshaw Interceptor, section 8. Depth of installation averages 10.7-12.2 m to the invert of the pipe. The entire pipeline will be installed in a tunnel (two-pass tunnel in soft ground construction). Excavated diameter for the initial lining is 3.07 m diameter. Much of the area along the Bradshaw 8 alignment has been dredged for gold. Local dredging operations varied between 6.1-9.15 m in depth. Geotechnical data indicated the presence of coarsed-grained soil mixture, typically containing cobbles (7.62 to 30.5 cm in diameter) with occasional boulders up to 45.7 cm in size. The tunnel boring zone, which is below the dredged areas, is consisted of fined-grained soils with medium dense to very dense combination of sands, silts, and clays. The ground water level is much deeper at about 19.8-21.3 m below ground surface. However, perched water was found at the tunnel boring zone during soil borings. Notice to proceed with construction is set for 15th November, 2004. Because of mobilisation and construction of a launching shaft, approximately 9 m in diameter and 14 m deep, tunnelling will not start until January or February 2005. The contractor has 560 calendar days to finish the project in June 2006. Designer is Montgomery Watson Harza. Visit www.srcsd.com/prj-bradshaw-8.html and www.insituform.com/corporate/corp_affholder.html 47/04.