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<br /> - ' 3P~ <br /> system key manholes by taking instantaneous flow measurements during the early <br /> morning hours. These measurements will be correlated with continuous flow <br /> monitoring results. Instantaneous flow measurements will be obtained using hand <br /> weirs as follows: <br /> 1. Flow isolation will consist of isolating a designated reach of sewer during the <br /> early morning hours (midnight to 6:00 a.m.) by measuring in the sewer as <br /> necessary to determine infiltration rates. ' <br /> ~~ <br /> 2. Where practical, weirs will be installed to measure the flows. Where a weir is <br /> not practical, the flow will be measured by ruler and velocity measurements. <br /> 3. For each location where flow isolation is performed, a flow isolation report will be <br /> completed. <br /> F. Dyed Water Flooding <br /> Dye testing will be performed on questionable or suspected infiltration/inflow or <br /> exfiltration sources in order that positive identification and quantifications can be made. <br /> The test results will be documented and photographed or videotaped. Both public and <br /> private sector dye water tests may be necessary. Prior notification and approval by <br /> residents will be required. The dye used during this test will be environmentally safe, <br /> biodegradable, and pose no hazard to receiving streams. <br /> G. Cleaning and Internal Television Inspection <br /> Prior to any televising and cleaning activities ADS will review the City's existing TV <br /> tapes and maintenance records. All pertinent information will be utilized where <br /> possible and included in the final report. <br /> ADS will provide internal color T.V. inspectj.on to be conducted on sewer mains <br /> specified and approved by the CITY. A closed circuit color inspection camera will be <br /> used. Sewer lines will be cleaned prior to video inspection. Three passes will be made <br /> with the jet rodder prior to cctv. Videotapes of the entire line along with written <br /> inspection logs will be provided. Videotapes will include a voice narrative of <br /> observations and show the footage counter of the camera position from the reference <br /> manhole. The television inspection log will be a comprehensive record and, will clearly <br /> describe the location of each defect in relation to an adjacent manhole. Other points of <br /> significance such as locations of service line taps, unusual condition, roots, storm <br /> sewer connections, broken pipe, presence of corrosion, observed infiltration/inflow and <br /> other discernible features will be noted. Information on line size, depth, type of pipe, <br /> etc. will be included on the log. <br /> Should the camera not be able to pass due to an obstruction (i.e., protruding services, <br /> dropped joint, etc.) then ADS will attempt to enter from the opposite manhole (reverse <br /> G:\O ALLAS\C 0 NTRA C lìS MAR Cb6. DO C April 11, 1997 <br />