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SECTION 02665 WATER SYSTEM B. The following table indicates the amount of calcium hypochlorite (65% available chlorine) that shall be added to each 100 feet of pipe to furnish a solution containing the minimum amount of free chlorine. Pipe Size Calcium Hypochlorite (65% available chlorine) 6" 2.1 oz. 8" 4.0 oz. 12" 8.0 oz. 16" 14.4 oz. C. After the installation has been tested and flushed the Contractor shall follow the disinfecting procedures as described in the Standard For Disinfecting Water Mains prepared by the AWWA C601-54. The Contractor shall become thoroughly informed on the requirements of the above mentioned manual and shall maintain a sufficient number of copies of same on the job site. D. It is intended that the chlorine be introduced at the extremities of the valves sections of p.)e through hydrants. If a hydrant is not located within 50 feet of either extremity of the pipe, a suitable tap shall be installed at Contractors expense to introduce the chlorine mixture or to bleed off the line to make certain the chlorine mixture has been uniformly distributed along the pipe. E. The Contractor may elect to use the Tablet Method which is described as follows: 1. The Contractor shall place hypochlorite tablets in each section of pipe and also in hydrants, hydrant branches and other appurtenances during construction. The tablets shall be attached to the upper portion of the pipe with a harmless adhesive, "Permatex" No. 2 gasket cement, or other approved material. 2. When the installation has been completed, the main shall be filled -ith water at a very low rate to insure the tablets dissolve in the same location as installed. Filling velocity shall not exceed one (1) foot per second. This water shall remain in the pipe for a 24-hour period. Chlorine residual tests shall be run by the Engineer at the beginning and end of the 24-hour retention period. Chlorine concentrations at the beginning of the period snail be not leas than 50 ppin and at the end of the period stall be not less than 25 ppm. F. A minimum of ten (10) days prior to allowing private connections to the new main, the heavily chlorinated or stagnant water shall be thoroughly flushed from the main until the chlorine concentration in the water tieing flushed is the same as the chlorine residual in the water system serving the area. 24 hours after flushing has been completed, another chlorine residual rest will be performed and the concentration in the new water main shall be no less than in the existing water system in the area. 7 KKE:1186