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instrumentation, electrical and piping components. Pumps with transducers affixed will <br />be installed in two of the three LVSCS riser pipes (the third pipe will be maintained as a <br />spare). These devices will be operated continuously to maintain less than two feet of <br />head on the lower geomembrane liner. This level will be used to manage the LVSCS and <br />higher levels will serve as an intensified monitoring and reporting condition as discussed <br />in Section 11.0 of this Project Description. For additional design information, refer to <br />Appendix 9, Volume V of this document. <br />7.2.1.6 Leak Detection System <br />A leak detection system ( "LDS ") comprised of a geomembrane -lined 1- foot -by -1 -foot <br />deep trench, will be installed beneath the SLF component of the composite liner system. <br />These LDSs are designed to intercept any potential leakage if it occurred through the <br />composite liner. The LDS trenches will be lined with 40 -mil smooth LLDPE <br />geomembrane on the bottom and one side, as with the approved and certified AGVLF <br />design. A 12 ounce /square yard nonwoven geotextile will then be placed in the LDS <br />trench and wrapped around a 3 -inch diameter PCPE pipe and 3/4 —inch minus leak <br />detection fill. The trenches will be excavated on a typical grade of 1 percent toward a <br />sump located at the edge of the SGVLF. Additional details on the design and <br />construction of the LDS are provided in Appendix 9, Volume V of this document. <br />7.2.1.7 Closure Drain <br />The SGVLF design also includes a closure drain. The purpose of the closure drain is to <br />provide a means to drain accumulated precipitation water from the SGVLF after <br />operations and neutralization has been completed to prevent overtopping of the PSSA <br />embankment. The closure drain consists of the following components: <br />• A closure drain that is located beneath the PSSA sump <br />• A thicker, 3 -foot layer of SLF underlying the lower geomembrane within <br />the portion of the PSSA that overlies the closure drain <br />• A passive drain consisting of five drilled shafts extending a minimum of <br />10 feet into the diatreme zone <br />During final reclamation of the SGVLF, after the PSSA water level has been reduced to 8 <br />feet or lower, the PSSA liner system will be punctured by drilling a borehole through the <br />PSSA and into the closure drain. This will facilitate long -term water drainage of the <br />PSSA. <br />Cripple Creek & Victor Gold Mining Company <br />Cresson Project Mine Life Extension 2 <br />7 -7 <br />