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EXHIBIT A Reservoir Inspection,Cleaning&Repair Bid#OSD 2021-604 B. Implement Best Management Practices (BMPs) for Discharge of Water Generated from Reservoir Cleaning Operations to existing storm drain facilities. C. Clean the storage facilities and remove all sediment accumulated on the facility floors, walls, and columns. D. Remove and replace the cathodic protection reference probe from inside the tank, if applicable. E. Conduct a comprehensive inspection of the facilities per Part II Section 4.D Inspection Report and Video. F. Implement measures to dewater sediments to less than 50% moisture and no free liquid, see Part II Section 5. Disposal of Sediments. G. Certify dewatered sediments as non-hazardous per specified methods and analysis. H. Off-haul, removal,and legal disposal of sediment. I. Site cleanup. 4. EXECUTION A. Disinfection All materials, personnel, and equipment coming in contact with potable water inside the tank or reservoir shall be disinfected in accordance with AWWA Standard C652-11.All disinfectants used in connection with this project shall be NSF approved for use in potable water. The Contractor shall provide evidence to this regard prior to mobilization. Reservoir entry shall be performed in a manner that protects water quality, and in accordance with Section 4 of AWWA Standard C652- 11. All equipment and clothing shall be disinfected immediately prior to entry into the facility.The diver and the clothing shall be disinfected after the diver is suited up.The dive suit shall completely encapsulate the diver with no bare skin exposed,this includes hands. There shall be no contact of the mouth or head with the water during inspection. The head shall be fully encapsulated by a helmet or dry suit hood with full face mask. Between uses, all equipment and clothing dedicated for potable water, underwater inspection work shall be stored in a manner that prevents both chemical and bacteriological contamination. Any runoff of chlorinated solution generated during disinfection of materials, personnel, and equipment, shall be properly contained in a bermed area and dechlorinated prior to discharge. B. Dichlorination, Disposal of Water, Filtration and Sediment Management All water and sediment pumped from the reservoirs shall be dechlorinated by the Contractor with Sodium Metabisulfite, Sodium Thiosulfate, Ascorbic Acid or equivalent and filtered through storage tanks, filter bags and/or Baker-type storage tanks prior to discharge into storm drain location point shown on the project drawings. The City reserves the right to prohibit the use of steel Baker-type tanks on sites where space is limited, poly-type tanks will be considered. The Contractor shall have available materials to create a temporary holding lagoon in the event runoff needs to be controlled or directed to a specific point of drainage. Effluent total chlorine residual shall be non-detectable(0.04 mg/L or lower),turbidity shall be less than 50 NTU, and pH shall be between 6.5 and 8.5. Water from all City fire hydrants and storage facilities is treated with chloramine. A representative sample(s) of the sediment collected from the potable water facility shall be analyzed and profiled to determine appropriate waste classification as specified in Part II Section Rate Sheet Page 2 of 8