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SCOPE OF SERVICES Consultant shall prepare and submit a geotechnical review and exploration plan for the City to review. Consultant shall obtain right -of -entry permits prior to exploration. Geotechnical borings within the railroad ROW or adjacent with the potential to foul the tracks will require SCRRA review with right of entry permit, training, and flagging. To reduce the delay in permitting and flagging time, borings will be placed outside of the railroad ROW. Consultant shall conduct subsurface investigation per AASHTO requirement and evaluate the results in accordance with specified testing criteria. AASHTO requires a soil boring at each bridge support location where substructure width is less than 100 feet; minimum of two borings are required per location where substructure width is greater than 100 feet. Since the bridge substructure width, measured from one edge of the pedestrian bridge to the other edge of the railroad bridge, is less than 100 feet, one set of borings is sufficient for both bridges. For retaining walls, a soil boring is required every 100 to 200 feet. For pavement, a boring shall be performed every 500 to 750 feet. Based on this information, consultant's geotechnical field investigations plan is presented in the table below. The proposed approximate boring depths will be raised if refusal is encountered. The boreholes will be excavated using a truck -mounted or track - mounted drilling rig. Asphalt concrete cold -patch will be used to replace asphalt that is removed by excavations. Consultant shall analyze the results and present them in the geotechnical report. The geotechnical report shall be prepared to include recommendations for design and construction of bridge foundations, earth retaining structures, cut and fill slopes, pavement, and drainage facilities Results obtained from the field and laboratory testing shall be used to establish an idealized soil profile and strength parameters for bridge and retaining wall foundation design, and slope stability and settlement calculations for the approaches. Consultant shall provide information on remediation measures if the site soils are corrosive to concrete or steel structures. R-value shall be used to determine composite pavement structural sections using Traffic Indices. CITY OF SANTA ANA SANTA ANA BOULEVARD GRADE SEPARATION ►L MARK THOMAS Design Element Number of Approximate Borings Depth (feet) Rail Bridge and 2 125 2 175 Pedestrian Bridge Retaining Walls 3 30 - 50 Roadway 3 5 - 10 Improvements Shoofly Track 2 10 Design A qualified geotechnical engineer shall prepare a Geotechnical Report for foundation design of the bridges, retaining walls, pump station, and roadway pavement and embankment. Sufficient borings and material samples shall be taken to determine the road structural section and slope stability. Consultant shall propose a Traffic Index (TI) for the all lanes and obtain City concurrence. It shall be the responsibility of the Consultant to notify Underground Service Alert and provide traffic control. Consultant shall tie position of boring locations, with elevation. The Foundation Report shall also include: • Nature of materials found on the site. • Liquefaction potential. • Any geological hazards that may exist and recommend mitigation measures. • Seismic design data in accordance with Caltrans 1 AREMA seismic design criteria. It shall be assured that the design parameters and potential construction difficulties are identified and addressed, together with the proper mitigation measures in the Geotechnical Report. For the bridge structure, alternative types of foundations shall be evaluated to insure the selection of the most suitable type of foundation. A log of Test Borings sheet shall be prepared and included as part of the report and as part of the structure plans. This Log of Test Borings sheet shall be prepared in accordance with Caltrans Standard Procedures. • Laboratory Testing - Bulk and disturbed 1 undisturbed samples shall be selected for laboratory testing. All tests shall be