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STORM WATER MANAGEMENT PLAN — MLE2 — AMENDMENT NO 10 — FOR <br />AREAS EXCLUDING AREQUA GULCH VLF AND SQUAW GULCH VLF <br />The proposed second Mine Life Extension ( "MLE2 ") for the Cresson Project will <br />require some changes to the existing Storm Water Management Plan ( "SWMP ") at the <br />facility and to the design for storm water management that was portrayed in MLE1 <br />Amendment No. 9 The design procedures that were employed in the formulation of the <br />Storm Water Management Plan for MLE1 were generally replicated for this current <br />MLE2 Storm Water Management Plan. However, there are two aspects of the MLE2 <br />Mine Plan that significantly affect storm water and therefore require revision of the MLE1 <br />Storm Water Management Plan. <br />• The Wild Horse Extension of East Cresson ( "WHEX ") mining area in Grassy Valley <br />will require special construction of storm water detention ponds because of the need <br />to bypass storm water from up- gradient basins around WHEX and because of the <br />close proximity of necessary detention ponds to the high -wall of the mining area. <br />Special construction of interim conveyance channels will also be needed. <br />• The perimeter of the North Cresson, Globe Hill and Schist Island mining areas will be <br />close to the Historic Buffer Boundary and there is a 2 acre limitation of encroachment <br />within that boundary. Special design and construction of storm water detention <br />ponds and conveyance channels are required to limit encroachment, meet that <br />constraint, and to accommodate the progression of mining in the North Cresson <br />mining area. <br />The Storm Water Management drawings listed on the previous page provide <br />details of the storm water basins, channels, flow schematics, progression of <br />development, and general specifications for constructing the dikes and channels. It <br />would be redundant to repeat those details in this narrative summary. Instead, this <br />summary report focuses on the basis and rationale for the configurations and the <br />designs portrayed on those drawings. <br />The design and configurations of facilities required in this MLE2 Storm water Plan <br />are based on information provided by the following reference materials: <br />1 Storm Water Management during Operations and for Final Closure at the Cresson Mine, <br />Amendment No. 9, AngloGold NA, Cripple Creek and Victor Mining Co. ", by Steffens and <br />Associates, Inc., March 2008. <br />