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Page 9 <br />kimley-horn.com 2828 Colby Avenue, Suite 200 Everett, WA 98201 425-708-8275 <br />Field Geotechnical Explorations <br />·Plan Field Exploration Program: HWA will plan and coordinate a two-phase geotechnical <br />exploration program for the project. Phase 1 will consist of conducting a series of <br />geotechnical borings along the proposed bridge alignment. Phase 2 of the proposed field <br />explorations will consist of conducting a geophysical survey to obtain shear wave <br />velocity measurements. Planning will include identifying the location of the explorations, <br />the development of traffic control plans, preparation of site-specific Health and Safety <br />Plan (HASP), and the coordination of required equipment and utility clearance. <br />·Conduct Utility Locates for Geotechnical Explorations: Prior to generation of the <br />geotechnical work plan, HWA will mark the proposed exploration locations and arrange <br />for utility locates using the Utility Notification Center. Utility location marks will be used to <br />verify proposed field exploration locations prior to the development of traffic control <br />plans. <br />·Second Utility Locate Site Visit: One week after marking and calling for utility locates; <br />HWA will make a second site visit to document the location of the marked subsurface <br />explorations. The subsurface utility locations will refine the locations of our proposed <br />explorations. <br />·Generate Geotechnical Work Plan Memo: HWA will prepare a Geotechnical Work Plan <br />Memorandum describing exploration means and methods associated with both Phase 1 <br />and Phase 2 of the exploration program. This work plan will be submitted to the design <br />team and the City for review and approval. The work plans will detail the type, location, <br />and extent of proposed field explorations along with logistics necessary to perform the <br />work such as traffic control plans and the designation of staging areas. The work plans <br />will also be used for utility locating clearances, permitting, and right of entries that may <br />be necessary to access the exploration locations. HWA assumes the City will acquire <br />and provide any required permits or right of entries at no cost to HWA. <br />·HASP: Prior to the beginning of the field investigation, HWA will prepare a site-specific <br />HASP for HWA internal use only. The HASP will be tailored to address specific site <br />health and safety concerns, and all field activities will be conducted in accordance with <br />HASP policies to ensure the health and physical safety of HWA staff working in the field. <br />·Conduct Phase 1 Explorations (Geotechnical Borings): HWA will conduct a series of six <br />(6) geotechnical borings along the bridge alignment to support various aspects of the <br />design. Five of these borings will be drilled to a depth of approximately 75 feet below <br />ground surface near the location of the proposed bridge abutments and interior piers. <br />Four of the six bridge borings are assumed to be drilled within Everett Community <br />College property and one of the bridge borings is assumed to be drilled within the traffic <br />lanes of Broadway. One (1) boring will be drilled at a depth of approximately 30 feet in <br />the vicinity of proposed retaining walls near the eastern bridge landing. All borings <br />conducted within landscape areas will be drilled with a track-mounted drill rig utilizing <br />plywood to avoid damage to the existing landscaping. Instrumented groundwater <br />monitoring wells will be installed within two borings to monitor and record seasonal <br />variations in groundwater levels. After construction of each monitoring well, the drillers <br />will develop the wells until the water is clear or an hour of well development has <br />occurred, whichever occurs first.