Laserfiche WebLink
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 inch 4.0 <br /> 8 inch 5 . 0 <br /> 10 inch 6. 5 <br /> 12 inch 7 . 5 <br /> 15 inch 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 />