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  The California Department of Transportation is inviting bids, deadline 2nd September, 2006 for contract 04-1123U4, project plans for construction on state highway in San Mateo County near Pacifica from km 4.7 to km 1 south of Lindamar Boulevard, including construction of the Devil's Slide twin bore tunnel (1,220 m). The tunnel will be 9.15 m wide, with 2.45 m wide shoulders, and will cross the San Pedro mountains. Contact Department of Transportation, Plans and Bid Documents, Room 0200, MS #26, Transportation Building, 1120 N Street, Sacramento, California 95814. Tel. +1 9166544490, fax +1 9166547028, e-mail Duty_Senior_District04@dot.ca.govThe sequential excavation method (SEM) will be employed to excavate and support the mined tunnels of both standard and enlarged cross sections, cross passages, equipment chambers, access passages, shotcrete canopies at south portals, and niches. The SEM utilizes NATM principles, modified so as to predetermine the various support measures required, defined as support categories, along different parts of the tunnels. The support requirements are determined in advance to suite generalized conditions along the tunnel and support measures are changed to maintain stability and safety of the excavation. The SEM utilizes a set of support measures for each category including the following: lattice girders, ground water drainage, grouted steel pipes (pipe arch canopy), rock dowels of different types, spiles of different types, face bolts and reinforced shotcrete. Read E-News Weekly 40/2004 & 37/2004. For full details, visit www.dot.ca.gov/hq/esc/oe/project_ads_addenda/04/04-1123U4/pdf/04-1123U4sp.pdf and www.dot.ca.gov/dist4/construction/Inquiries/04-1123U4_inquiry.html. Visit also www.dot.ca.gov/dist4/dslide 31-32/06.The California Department of Transportation (Caltrans) opened the bidding process on 21st November, 2006 for potential builders of a tunnel under Montara Mountain on the coast of San Mateo County that would serve as a bypass to the Devil's Slide area on state Highway 1. The department now has 30 calendar days to choose between two separate bids. One bid, proposed by Kiewit Pacific, would cost nearly USD272.4 million, USD32 million over what Caltrans predicted, and the construction work would take an estimated 1,500 days. Another bid was put up by a joint venture of three construction companies - Shea, Traylor and Atkinson. Their offer was nearly USD50 million more costly than the first and the companies estimate it would take 1,900 days to complete the tunnel. After a winning bid is selected, work on the tunnel could begin as early as summer 2007. Click us/93. Visit www.dot.ca.gov/dist4/dslide/index.html 49/06.



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