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of the structure as well as the peak storm water flow estimates. These estimates are developed <br />using practical graphic- or computer -based modeling techniques, in this case the SEDCAD4 <br />model. <br />The temporary and permanent storm water diversion systems for the SGOSA and ECOSA and <br />other areas of the Cresson Project have been designed to safely pass the flows computed to arise <br />as the result of a 100 -year, 24 -hour precipitation event (3.5 inches). Detention structures have <br />also been designed so that the most downgradient structure retains the flows from two 10 -year, <br />24 -hour storm events with spillways capable of passing the runoff from a 100 year, 24 -hour <br />storm event. <br />CC &V will construct and maintain sediment control measures where needed during operations. <br />This will consist of the installation of BMPs, concurrent reclamation, and implementation of <br />other effective methods as appropriate. The type of structure used in a particular area will be <br />based on site specific conditions and constraints as well as the anticipated longevity of the <br />structure. The Storm Water Management Plan will be updated as needed to address the <br />disturbance associated with MLE2 and will provide information on locations and types of BMPs <br />to be used as well as periodic inspections of the storm water controls to maintain effectiveness of <br />the controls. <br />The storm water management designs for SGOSA and ECOSA are provided in Appendix 12 in <br />Volume VI of this document. The storm water management designs for the SGVLF are provided <br />in Appendix 9 in Volume V of this document. The storm water management designs for the <br />AGVLF were approved as part of MLE and will not require modification as a result of MLE2. <br />The storm water management designs for areas of the Cresson Project are summarized below. <br />10.2 North Cresson Mine Area and SGOSA Diversion and Sediment Control <br />The storm water management designs, more specifically shown on Sheets 5 and 6 of Appendix <br />12, Volume VI, show storm water control facilities and proposed configurations of the west side <br />of the Cresson Project (Poverty Gulch) in their current conditions (Details 1 and 5), during the <br />development of mining (Details 6 through 12), and following reclamation (Detail 13). Sheet 5 <br />also includes a schematic showing the storm water flow and design dimensions for the channels <br />and sedimentations ponds. Sheet 6 provides details of the EMP Ponds, channel profiles, and <br />general specifications for construction of the EMP ponds. <br />Storm water management design on the west side of the Cresson Project, above the City of <br />Cripple Creek, provides design specification to ensure that facilities are effective, and conform to <br />Cripple Creek & Victor Gold Mining Company <br />Cresson Project Mine Life Extension 2 <br />10 -2 <br />