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Three new terminal EMP Structures will be constructed (EMP -09, EMP -21, and <br />EMP -22) while one reconstructed interior structure (EMP -08a) will be used on a <br />temporary basis. EMP -8a is an existing depression area on the flank of the Schist Island <br />pit of North Cresson that is low enough in elevation and accessible to receive runoff from <br />the higher terrain of the North Cresson hillside. It has the required capacity of a terminal <br />EMP pond, but will drain by percolation into the diatreme. EMP -09 and EMP -21 will be <br />constructed in 2013 and 2014 to replace the function of EMP -08a when it is obliterated <br />by mining. <br />Accordingly, the schematic in Figure 2 shows the current routing to EMP -08a as <br />well as the future routing to EMP -09 and EMP -21 once those ponds are built. <br />SPECIAL CONSIDERATIONS FOR UPPER GRASSY VALLEY STORM WATER MANAGEMENT <br />The drawings show the essence and details of the plan for Poverty Gulch and <br />North Cresson Storm Water Management. There are certain specific conditions that <br />have been considered and addressed in the design, and are describe below. <br />Limitations on Historic Buffer Encroachment and the Effect on Pond Design <br />Permit conditions required by the Town of Cripple Creek include the stipulation <br />that no more than 2.0 acres of additional disturbance related to MLE2 will occur within <br />the boundary of the Historic Buffer. The Historic Buffer Boundary is very close to the <br />mining pit limits in many areas. Consequently, the construction of ponds and channels <br />must generally be inside or close to the mining boundary. The preliminary design <br />presented on the Drawings show that plan to be feasible as long as the ponds and <br />channels are constructed in a rigorous schedule. Three EMP structures (EMP -09, EMP - <br />21, and EMP -22) will be located immediately adjacent to the Historic Buffer Boundary, <br />although only EMP -09 will cross and encroach into the Historic Buffer by about 1.2 <br />acres. <br />Existing roadways will be used where feasible for construction of storm water <br />channels. The disturbance within the historic buffer will be minimized by implementing <br />that approach. Existing drainage ditches will be re- graded and reshaped to the minimum <br />size shown on the table of Detail 3, Sheet 5. The only encroachment into the Historic <br />Buffer will be the Lower South interceptor ditch will be built within an existing roadway, <br />Client: CC &V Gold Mining Co. <br />Title: Storm Water Management, MLE2 <br />2/2/12 <br />Page 13 <br />