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1 _ <br /> 1 <br /> EXHIBIT A - SCOPE OF WORK - SUPPLEMENT 2: <br /> BROADWAY BRIDGE REPLACEMENT <br /> PHASE III - FINAL DESIGN, BID ASSISTANCE, AND <br /> CONSTRUCTION PHASE ENGINEERING SERVICES <br /> Project Background <br /> The Broadway Overcrossing carries traffic from Broadway Street facility over the Burlington <br /> Northern Santa Fe (BNSF) railroad tracks between Hewitt Avenue and California Street in <br /> Everett, Washington. Broadway OC is a vital link in the transportation network within the City <br /> of Everett. Based on the City's recent traffic count studies, the Bridge serves about 2500 daily <br /> truck crossings and 30,000 vehicles. <br /> The original Bridge was built in 1912 with a timber deck supported by steel stringers. In 1931, <br /> through a major rehabilitation, the deck was replaced with concrete encased steel stringers and a <br /> concrete slab. To account for the weight of concrete deck, additional stringers were added into <br /> Bridge superstructure. Vertical stiffeners were also added to the cap beams right underneath the <br /> locations of stringers. <br /> Since 2001, Bridge Inspection Reports have indicated the Bridge's very poor conditions.During <br /> 2008 Bridge Inspection cycle, TranTech engineers noticed extensive damage to concrete <br /> sidewalk soffit, steel cap beams, and exterior stringers supporting roadway. <br /> Following inspection activities, TranTech engineers performed load rating analyses on the <br /> Broadway Overcrossing BNSF. Based on the observed conditions of the Bridge, load rating <br /> results indicated that the maximum allowable truck load on the Bridge is limited to 9, 12,and 14 <br /> tons for AASHTO-1,AASHTO-2, and AASHTO-3 trucks. <br /> Due to vital nature of this Bridge and to validate the aforementioned load restriction <br /> recommendations, the City of Everett Public Works Department tasked TranTech to perform <br /> structural assessment of the Bridge. This task included two subtasks as following: the first <br /> subtask, performed by Mayes Testing Engineers, included material testing activities to gain <br /> further insight to the conditions of the Bridge; the second subtask included new load rating <br /> activities based on the information obtained from subtask 1. <br /> Following the condition survey sampling and testing, a new load rating analyses of the Bridge <br /> was performed based on the new information provided through field experiments. The new load <br /> rating results confirmed the prior recommendations on load restrictions on the Bridge. The <br /> Structural Assessment Report's recommendation for elimination of this load restriction was to <br /> replace the Bridge. In order to eliminate this load restriction, the City has applied for and has <br /> 3 <br />