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Surge Riser <br />A portion of the existing 12 -inch HDPE pipeline that connects to a riser on the west side <br />of the valley was connected to the diesel pump tee. This riser is used to absorb <br />pressure surges caused by pump start-up or shut-down. <br />Proiect Construction <br />The construction of the new 5 Dam Seepwater pipeline began in early September 2008. <br />The construction started at the "1/2 way cutout' end of the new pipeline and progressed <br />back towards the high point vent. The actual "% way cutout" connection was the last <br />section of the new pipeline to be installed. <br />There was a minor change in the pipeline routing requested by the contractor. It was <br />decided to route the pipeline around some power pole guy wires at the groin of 5 Dam <br />rather than place the pipeline under the guy wires. This change did not affect the <br />operation of the pipeline. The pipe trench is outside the limits of 5 Dam and did not affect <br />its structure. Other than this change, the pipeline basically followed the planned route. <br />The pipeline was specified to be buried with a minimum of 5 feet of ground cover over <br />the top of the pipe to prevent any issues with the water in it freezing and protection from <br />road construction work. <br />Because the existing seepwater system had to remain operational until the new pipeline <br />was ready for use, it was necessary to leave much of the existing pipeline in the ground <br />and install the new pipeline beside or in some locations over the top of it. <br />There were delays in receiving the stainless steel spool pieces required for the project. <br />These delays contributed significantly to overall delay of the project completion. <br />Construction Issues <br />The biggest challenge for the project construction was the weather. The project started <br />late and this caused difficulties as the weather changed from summer to winter <br />conditions. This slowed excavation, caused freezing problems with bedding and backfill, <br />and slowed down the entire work process. <br />