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9 <br /> EXHIBIT A-1 <br /> Scope of Services <br /> BROADWAY BRIDGE REPLACEMENT <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 2,500 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 /> the Bridge superstructure.Vertical stiffeners were also added to the cap beams right underneath <br /> the 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 the vital nature of this Bridge and to validate the aforementioned load restriction <br /> recommendations,the City of Everett Public Works Department granted TranTech a task to <br /> perform a structural assessment of the Bridge. This task included two subtasks as following: first <br /> subtask performed by Mayes Testing Engineers includes material testing activities to gain further <br /> insight to the as-is conditions of the Bridge; second subtask included new load rating activities <br /> based on the information obtained from subtask 1. <br /> Following the condition survey sampling and testing,new load rating analyses of the Bridge was <br /> 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. <br /> In order to eliminate this load restriction, the City has applied for and has been successful in <br /> securing federal funds for engineering to replace the deteriorated Bridge structure. <br /> 13 <br />