The Baumgartner Tunnel JV, including Frontier Kemper and Gunther-Nash, is to begin boring a 6,184 m-long 3.66 m-diameter gravity tunnel for the Metropolitan St. Louis Sewer District, as part of the Lower Meramec River System Improvement project. Under an agreement with the state of Missouri, the district must close the overloaded Baumgartner lagoon by 31st December, 2006 or face a penalty for each day the lagoon operates after the deadline. The USD45 million tunnel is part of a USD217 million project which includes also a sewage treatment plant on Fine Road. Sewage will travel in a reinforced concrete pipe inside the tunnel. The pipe will be 2.44 m in diameter. The space between it and the rock will be filled with grout.A reconditioned Wirth TBM 350-400E will be used about 58 m below ground. The tunnel will cross the Meramec River twice. Three major shafts will be constructed, namely a lift station approximately 30 m in diameter and 61 m deep, the 10.4 m-diameter exit shaft and the 11 m-diameter screen shaft. The cutting head is driven by 24 pressurised cylinders. Conveyor belts will haul the bored rock to a shaft at the treatment plant. The tunnel is slated to be finished by November 2005. Visit www.wirth-europe.com and www.frontier-kemper.com 33-34/04.