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<br />3. The length of the siphon would be increased and cost associated with the blasting of <br />rock formation will undoubtedly be incurred. <br /> <br />The advantages and disadvantages of each alignment will be evaluated during the survey and <br />design phase of construction. The option showing to yield the least overall construction costs <br />will be selected. <br /> <br />Alternatives <br /> <br />Three alternatives have been evaluated: <br />1) The No Action Alternative <br />2) Sleeve (Slip Line) the Existing Siphon <br />3) Siphon Replacement. <br /> <br />Alternative 1 - No Action <br /> <br />The No Action Alternative consists of simply not taking any remedial action to rehabilitate the <br />Beaver Creek Siphon. This would result in using the siphon until the PRBD Company /' <br />experiences catastrophic failure. The cost associated with the resulting property damage and /' <br />loss of agricultural production, depending on the time of failure, could escalate the expense of <br />replacing the siphon by a conservative estimate of two to three times and beyond. <br /> <br />Alternative 2 - Sleeving or Slip Line <br /> <br />To sleeve or slip line the existing siphon would eliminate the unknown problems associated with <br />excavation of boggy soils. A new line would simply be pulled through the old line and the sleeve <br />would be connected to larger diameter pipe on each end of the siphon to "load" the pipe and <br />create enough velocity to deliver approximately 37 cubic feet per second at the outlet works. <br />The cost to slip line the siphon was projected by United Pipeline Systems, on 4/29/2003, to cost <br />approximately $187,000. This cost estimate includes the pipe (28-inch) and the slip line only. It <br />does not include the required excavation at various increments along the siphon to allow <br />constructors to pull the line through the existing siphon. <br /> <br />/ <br /> <br />There are three unknowns regarding this alternative. First, is the condition of the existing siphon <br />able to allow the sleeving process to be successful accomplished? Second, the cost associated <br />with the required excavation and unforeseen problems associated with this alternative cannot be <br />determined until actual construction begins. Third, designing the system to allow for the <br />approximate 37 cubic feet per second discharge at the outlet works could be difficult, especially if <br />a section of smaller diameter pipe (or more) is required to by-pass some obstruction(s) in the <br />existing siphon. <br /> <br />./ <br /> <br />Alternative 3 - Siphon Replacement with 30-inch PVC <br /> <br />The siphon covers a distance of approximately 2,300 feet. Under this alternative, the siphon <br />would be replaced by a 30-inch PVC pipe. Excavation would require a trench of approximately <br />2,300 feet in length and a depth of approximately six feet deep. <br /> <br />Selected Alternative (Preferred Alternative) <br /> <br />Alternative Three - Siphon Replacement with 30 inch PVC is the preferred Alternative. <br />PRB Ditch Company Page 11 of 15 <br />Siphon Replacement Feasibility Study <br />May 2003 <br />