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other foreign objects shall be placed around the anode to a minimum cover of <br /> one foot above the anode. Five gallons of water shall be poured on each anode <br /> and the one foot of backfill. Remainder of the trench shall then be backfilled with -_ <br /> native soil. During installation, anodes shall not be supported or handled by use <br /> of attached wires. <br /> B. The Engineer shall measure and record the open circuit potential of all zinc <br /> anodes prior to backfill. Zinc anodes shall measure at least —1100 millivolts <br /> versus a copper, copper-sulfate reference electrode. The reference cell shall be <br /> placed on the cloth bag surrounding the anode and water shall be used as <br /> required to obtain the measurement. Anodes which do not meet the above <br /> potentials shall be rejected by the Engineer and shall be removed from the <br /> project site by the Contractor. Anodes which are buried prior to testing and the <br /> open circuit potential does not meet the -1100 millivolt criteria shall be rejected <br /> by the Engineer and shall be replaced with acceptable anodes at the Contractor's <br /> expense. <br /> 3.04 ZINC RIBBON ANODE <br /> A. The ribbon anodes shall be installed horizontally atop the pipe sections, where <br /> indicated. The ribbon shall be installed at pipe 2 feet below grade. The ribbon <br /> shall be laid straight in the trench, and installed directly above the pipe. Care _ <br /> shall be exercised during installation to prevent damage to the pipe, anode or the <br /> wire splices. All splices between anode to wire and anode to anode shall be <br /> made using the steel core inside the anode and a copper split bolt connector, as <br /> shown in the drawings. The ribbon anodes shall be clamped together with <br /> ground clamps, as shown in the drawings. After placing ribbon anodes in the <br /> trench, native soil, free of rocks and other foreign objects shall be placed around <br /> the anode to a minimum cover of one foot above the anode. Remainder of the -- <br /> trench shall then be backfilled as indicated in the Civil drawings. During <br /> installation, anodes shall not be supported or handled by use of attached wires. <br /> B. The splices between the zinc ribbon and the wires shall be made in accordance <br /> to the drawing details. All splices shall be inspected by the Engineer prior to <br /> backfill. Any splices backfilled without approval shall be uncovered by the _ <br /> Contractor for inspection. <br /> 3.05 ZINC GROUNDING MAT --- <br /> A. A zinc grounding mat shall be installed at each AC mitigation test station, <br /> cathodic protection test station and blow off along the 18-inch water transmission <br /> mains from Station 320+30 to 422+60± along 11th Street, which are in close -- <br /> vicinity of high voltage transmission line. <br /> B. Install the grounding mat centered over the test station or appurtenance, at a _ <br /> depth of 6 inches below grade. Provide a minimum of 6 inch layer of gravel in <br /> non-paved areas. In paved areas combined vertical magnitude of the pavement <br /> and the gravel layer shall be a minimum of 6 inches thick. The gravel shall be of <br /> a 0.5-inch diameter minimum. <br /> C. The grounding mat shall be connected to the pipe with a minimum of two (2) #4 — <br /> AWG HMWPE cables by means of exothermic welds. Special care shall be <br /> Division III-143 NEI Phase II Water and Sewer <br /> July 2007 CIP Nos. 7468,7589,7590 <br />