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<br />123~ <br /> <br />c. Provide rim to invert elevation data; <br /> <br />d. Provide data to confirm or revise existing map information; <br /> <br />e. Help establish sewer line maintenance needs; and, <br />f. Prioritize lines for TV inspection. <br /> <br />Inspection will identify sources from the manhole cover to the manhole <br />bench and trough area. Each manhole inspected will be entered and every <br />line entering the manhole will also be partially inspected by lamping. <br />Inspection of each line will be by means of a flashlight and mirror. <br />The information allows for evaluation of a manhole's structural <br />integrity and potential for leakage, as well as gathering pertinent <br />information for rehabilitation design. Selective photographs will be <br />used to document typical I/I sources and special conditions. Field <br />crews have been trained in confined spaced entry procedures and the most <br />current technology in safety equipment will be used. <br /> <br />It is estimated that comprehensive inspection or inspection attempts at <br />20 manholes will be made. A reasonable attempt will be made to inspect <br />manholes. Manholes which are buried or are not accessible because of <br />shrubbery, fences, or dogs will be noted as such and reported to the <br />OWNER. A second inspection attempt will be made if access can be <br />provided within a reasonable time after completion of the initial <br />inspection attempts. <br /> <br />~ <br /> <br />4. Television Inspection. Selective television inspections will be <br />defined to identify pipe infiltration sources, pipe structural <br />condition, and to locate inflow source identification from dyed water <br />testing. Results of any smoke testing, line lamping, and dyed water <br />testing will be used to select lines to be televised. Television <br />inspection field activities will be performed by the OWNER. <br /> <br />It is estimated that 3,000 feet of sewer line will be selected for <br />television inspection. Video tapes will be reviewed and summarized on <br />computer coded field forms and input into a database for storage, <br />sorting and retrieval. ' <br /> <br />5. Smoke Testing. Selective smoke testing will be performed to <br />identify sources of infiltration and inflow in both the public and <br />private sectors of the sewer system. Notification of each building in <br />the test area will be made by distributing door hanger notices one week <br />prior to the test. Smoke testing will be performed on single sewer <br />segments for each test, if possible. Air flow will be restricted at the <br />upstream and downstream sewer section and a non-toxic smoke will be <br />pumped into the sewer section with a blower. All sides of buildings and <br />the entry area in the vicinity of the sewer segment being tested will be <br />investigated by a three or four man crew. Testing will include <br />observation of suspect private sector sources such as area drains and <br />downspouts piped underground. Detailed sketches will be made of <br />positive and suspect sources. Selective photographs will be taken for <br />documentation of confirmed sources and to record suspect sources for <br />subsequent dyed water testing. Recommendations for television <br />inspection of the sewer segment will be made. <br /> <br />06/02/93 <br /> <br />A-II <br />