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HYDROSTATIC TESTING <br />The 24-inch HDPE Storke pipeline was hydrostatically tested after construction to <br />verify its water-tightness, and the strength of the fusion welds. The test procedure used <br />was the test described in the Plastic Pipe Institute's Handbook, and is called the "Non- <br />Monitored Make-up Water Test." This test involves filling the line to be tested with water, <br />pressurizing the line to the specified pressure, then releasing a small amount of the test <br />pressure and monitoring the pipeline pressure for several hours. A small amount of <br />pressure loss during the monitoring period is allowed. If no leaks are found, and the <br />pressure stays within the allowable limits for the required time, the pipeline is considered <br />to be watertight and acceptable for use. <br />The test pressures described above are based on the HDPE pipe SDR. In this <br />case, the pipe was pressurized to 150 psi (at the lowest end of the pipe, at the PT) and <br />this pressure was held for a period of four hours. After, four hours, the pressure was <br />reduced to 140 psi. This pressure was monitored for an additional one-hour- "hold" <br />period. If the pipeline pressure stayed above 133 psi (a 5% decrease), the pipeline was <br />considered to have passed the hydrostatic test. In both phases of this test, the pressure <br />held steady during the one-hour hold period, and virtually no pressure decrease was <br />measured. <br />For this first series of hydrostatic tests of the pipeline, clean water from a fire <br />hydrant near the Discharge Vault was used to fill the pipeline. This was done so that if <br />the pipeline did fail during testing, any water that was released would be clean, <br />minimizing any environmental impact. No releases of any water occurred, and the <br />hydrostatic testing was passed without any problems. <br />The pipeline was actually hydrostatically tested in two phases. The first phase <br />involved testing the upper section of the pipeline, from the Discharge Vault to the first <br />cleanout above the PT. This was done so that any problems with the upper section <br />could be discovered before it was completely buried. The testing was performed on <br />10 <br />