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properties will be based on analytical information from publicly available reports and the vegetation type and <br />conditions at the site. If reports can be found with the water chemistry information, assumption will be made <br />based on the known freshwater conditions at the site and factors that can be assigned within the corrosion <br />guidance documents. <br />Otak will consult with a testing provider to determine cost and methods to take core samples of the existing <br />culvert and have the level of corrosion analyzed by a steel materials lab. If the City requests the testing to be <br />performed, a request for authorization of Management Reserve funds will be made to cover the vendor expenses <br />for testing. <br />Otak will assess optional materials for coating or slip -lining of the existing culvert to extend the service life that are <br />compatible with the proposed Alternative 1 flood gate retrofit and fish passage criteria. Criteria to be considered <br />includes SRT/MTR actuator arm installation inside the culvert, aquatic organism compatibility, and abrasion. <br />TASK 6.4 DELIVERABLES <br />• Existing Culvert Condition Assessment and Technology Compatibility - narrative of findings for future Phase II <br />Alternatives Analysis Report (Draft and Final, electronic pdf) <br />TASK 6.4 ASSUMPTIONS <br />• City will provide one list of consolidated comments on the draft narrative of findings for future Phase II <br />Alternatives Analysis Report. Comments will be addressed and incorporated into the narrative. <br />6.5 Alt 1 Retrofit Option Feasibility Study - Integrating STR/MTR <br />Otak will develop schematic design plans for Alternative 1 focusing on retrofitting the existing culvert with a side <br />hinge self-regulating tide gate with muted tidal regulator (SRT MTR). The schematic design plans are estimated to <br />include the following sheets: <br />o Culvert Cross Section and Elevation (depicting MTR actuator integration) <br />o Culvert Inlet Treatment Details integrating MTR float apparatus <br />o Culvert Outlet Details for installing an SRT gate at the existing outlet concrete headwall and <br />apron structure <br />Otak will reach out to a regional manufacturer of side hinge self-regulating tide gate with muted tidal regulators <br />(SRT MTR) to discuss constructability issues related to retrofitting the existing culvert with this technology <br />including issues related to debris interrupting gate function, mitigating design approaches, and anticipated <br />maintenance. A meeting with be conducted with the manufacturer representative, City staff, and Otak engineers <br />including hydraulic and structural engineers. Details of a SRT MTR that can be incorporated into the schematic <br />plans will be requested from the manufacturer. <br />• This task is intended to understand the viability of retrofitting the existing culvert and address the following <br />issues: <br />• Compatibility of MTR actuator arm technology with a 208 LF length of culvert. <br />• Compatibility of slip lining or CIPP technology with MTR actuator technology running inside/on the ceiling <br />of the culvert. <br />• Can the actuator arm be installed in a new, parallel conduit? <br />• What is the risk of debris entanglement on MTR float system. <br />• What is the risk of debris entanglement on the actuator arm if it runs through the culvert the existing <br />culvert? <br />• How much conveyance capacity is reduced with the actuator arm being installed inside the current <br />Otak — Scope of Work <br />49 <br />