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shall the infiltration exceed 50 gal/day/inch of pipe diameter/mile of pipe (or 0.4 <br />gal/hr/in/ 1000 ft). <br />B. Exfiltration Test: Exfiltration testing shall be conducted by filling the system with water <br />and measuring the amount of exfiltration. Water shall be added to the system until the <br />manhole with the lowest top elevation (test manhole) of that portion of the system being <br />tested is filled to within 24 inches of its top. Testing of the system shall be segmented <br />such that the difference between the top elevation of any two manholes being tested does <br />not exceed 2 feet. Testing shall proceed for a continuous period of four hours with <br />exfiltration amounts measured by adding known amounts of water to the beginning <br />water level in the test manhole. In no case shall exfiltration exceed 100 gal/day/inch of <br />pipe diameter/mile of pipe (or 0.8 gal/hr/in/1000 ft). Leakage from any manholes shall <br />be included in the pipe exfiltration determination. <br />C. Air Leakage Test: Air leakage tests may be required in lieu of infiltration/exfiltration at <br />the option of the Owner. Air leakage tests on PVC gravity sewer pipe shall conform to <br />ASTM F-1417. The testing shall be by compressed air from manhole to manhole. Plugs, <br />caps and branch connections must be secured against blow -off during the test. The pipe <br />and manholes shall be free of water during the test. The pipe shall be tested at 3.5 psi in <br />excess of the groundwater pressure above the pipe. For each foot of water above the <br />pipe at the deepest point, the air pressure shall be increased by 0.43 psi. The minimum <br />time for the air pressure to drop by 0.5 psi shall be: <br />Pipe Size Time in Minutes <br />6 <br />inch <br />4.0 <br />8 <br />inch <br />5.0 <br />10 <br />inch <br />6.5 <br />12 <br />inch <br />7.5 <br />15 <br />inch <br />9.5 <br />D. Test Failures: Should a test failure occur, necessary repairs shall be accomplished by the <br />Contractor and the test repeated until within the established limits. The Contractor shall <br />furnish the necessary labor, water, and all other items required to conduct the required <br />testing and shall perform the necessary system repairs required to comply with the <br />specified test. If the water supply is from the County's potable water system, a meter is <br />required. Contractor is responsible for all costs associated with retesting. <br />END OF SECTION <br />02533 - Testing Gravity Sewer System <br />02533= 2 <br />J <br />