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supplemented with a solution collection piping system placed directly over the upper <br />geomembrane liner at the base of the DCF. Additional information, drawings and <br />technical specifications for the HVSCS can be found in Appendix 9, Volume V of this <br />document. <br />The primary solution pipes will consist of three 28 -inch standard dimension ratio <br />( "SDR ") 11 HDPE pipes located along the base of the SGVLF PSSA. Together, these <br />pipes are sized to provide capacity for the maximum solution application flow rate of <br />17,000 gpm with a factor of safety (each sized for 7,083 gpm) under gravity flow <br />conditions. Secondary solution collection pipes, which will vary in size from 8- to 20- <br />inch diameter PCPE pipe, will direct solution collected from 4 -inch diameter highway <br />grade tertiary pipes that are on 95 -foot typical centers into the primary solution collection <br />pipes. General layout and calculations are provided in Appendix 9, Volume V. <br />Solutions within the SGVLF PSSA will report to the solution collection sump and to the <br />solution recovery riser system. The riser system consists of four 24 -inch diameter steel <br />risers that will house vertical turbine pumps. The steel risers will be manifolded together <br />to the primary HVSCS pipes to enhance solution recovery. Each riser will be constructed <br />of stainless steel, slotted well casing and carbon steel blank casing. The screened section <br />for each riser is a minimum of 22 feet long. The riser pipes and riser base plates have <br />been designed to withstand the down -drag forces resulting from the settlement of 110 feet <br />of ore, the nominal ore depth at the PSSA sump location. <br />Emergency power from four diesel powered generators is provided to operate the HVSCS <br />pumping system in the event of a power outage at the Squaw Gulch processing facilities. <br />A transducer will be installed inside each of the HVSCS vertical -riser pipes to measure <br />solution levels in the PSSA. A solution level corresponding to 80 percent of the PSSA <br />capacity will be calculated and provided as part of the Certification Report submitted to <br />the OMLR after construction is completed. This level will be used to manage the <br />SGVLF PSSA and higher levels will serve as an intensified monitoring and reporting <br />condition as discussed in Section 11.0 of this Project Description. <br />7.2.1.5 Low Volume Solution Collection System <br />The LVSCS in the SGVLF is similar to the LVSCS approved and certified for the <br />AGVLF. The LVSCS will overlie the lowermost geomembrane liner in the PSSA. The <br />LVSCS will be equipped with three 18 -inch diameter riser pipes connected together to <br />create a manifold within the PSSA sump. A small building constructed at the ground <br />surface will enclose the three 18 -inch diameter LVSCS riser pipes and associated <br />Cripple Creek & Victor Gold Mining Company <br />Cresson Project Mine Life Extension 2 <br />7 -6 <br />