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CITY OF EVERETT SPECIAL PROVISIONS <br /> Iof the backflow preventer and adjacent downstream appurtenances, valves or <br /> couplings for example, with straight hypochlorite solution prior to their installation. <br /> I 7-09.3(24)E Preventing Reverse Flow <br /> Provide a State Department of Health approved backflow preventer installed in the <br /> connecting line before making a connection between the existing distribution <br /> I system and water lines constructed under this Contract that have not been <br /> flushed, disinfected, and tested. Install backflow preventer upstream of temporary <br /> fill hoses and disinfectant injection equipment. <br /> I 7-09.3(24)F Chlorinating Valves, Hydrants, and Appurtenances <br /> Operate valves, hydrants, and other appurtenances during the disinfectant contact <br /> interval for newly-laid pipe while filling the pipeline with the disinfectant chlorine <br /> I solution and the main is under normal operating pressure. Normal operating <br /> pressure is the pressure the existing distribution system provides through the <br /> temporary backflow protection device. <br /> I 7-09.3(24)G Chlorinating Connections to Existing Water Mains and Water <br /> Service Connections <br /> Chlorinate connections to existing water mains in accordance with the following <br /> I sections of the most recent revision of AWWA Standard C651: <br /> Section 4.6 - Final Connections to Existing Mains, <br /> Section 4.7 - Disinfectant Procedures When Cutting Into or Repairing Existing <br /> I Mains, and <br /> Section 4.8 - Special Procedures for Caulked Tapping Tees <br /> Swab the internal surfaces of closure fittings with a 5 to 6 percent chlorine solution <br /> I that can be found in liquid household sodium hypochlorite bleach. <br /> 7-09.3(24)H Final Flushing and Testing <br /> Notify the City Utilities Division, Environmental Monitoring and Compliance (EMC) <br /> I staff at least five business days prior to requiring EMC staff to collect samples and <br /> measure the chlorine concentration of the disinfectant solution placed in the new <br /> main. EMC staff will collect and measure samples at the start and at the end of <br /> Ithe disinfectant contact period. <br /> Provide sample taps as noted in 7-09.3(24)1 to allow EMC staff to collect at least <br /> one set of disinfectant concentration, coliform bacteria and free chlorine samples <br /> I from both ends of new mains, at the end(s) of each cross or branch, and every <br /> 1200 feet along the main. <br /> Notify EMC staff at least five business days prior to requiring having EMC staff <br /> Icollect final coliform bacteria and free chlorine residual samples. <br /> The City of Everett EMC staff will collect bacteriological and disinfectant residual <br /> samples for submitting to Washington State Department of Health, Drinking Water <br /> I Division certified laboratory for testing. EMC staff will immediately notify <br /> Contractor and Engineer upon receiving analysis results. <br /> Upon receiving passing test results, flush disinfectant solution from the newly-laid <br /> I mains until the replacement water throughout the length of the main tests having a <br /> level of free chlorine residual representative of the distribution system water <br /> supply. <br /> 1 7-09.3(24)1 Sample Collection Taps <br /> Provide water sample collection taps at each required sampling location in <br /> accordance with COE Standard Drawing No. 525 and 526 and as described in <br /> Ithese Special Provisions. <br /> Sewer Regulators R4 and Division 7—STORM, SEWER,WATER May 2017 <br /> R39 Modifications <br /> IWO No.—UP3633 SP-167 <br />