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EXECUTIVE SUMMARY <br />The proposed Mine Life Extension ("MLE") for the Cresson Project will require <br />some minor changes to the existing Storm Water Management Plan at the facility and to <br />the design of structures that comprise the Storm Water System. Drawings CCVA9SA1 <br />and CCVA9SA2 illustrate the proposed MLE storm water management system during <br />operations and after reclamation and closure ("closure"), respectively. <br />The proposed revisions to the storm water management system conform to the design <br />criteria that were previously approved for Amendment No. 8 as well as the design criteria that <br />has been used by others to design the storm water controls associated with the Phase 5 <br />Extension to the Valley Leach Facility. <br />The extension of the Schist Island portion of the North Cresson Mine and <br />development of the Globehill portion of the North Cresson Mine areas to the west and <br />northwest will result in more land disturbance during near-term growth medium salvage <br />and mine area development, but overall less land contributing to storm water in the post <br />closure configuration, following backfill activities and after closure. <br />The storm water system along the western permit boundary was previously designed <br />and approved as part of Amendment No. 8 to include four terminal ponds with spillways. <br />Storm water runoff was to be collected in diversion ditches along benches/terraces on <br />the west flank of the Squaw Gulch Overburden Storage Area (SGOSA). That runoff <br />would flow either south to EMP007 or north to proposed EMP008 and EMP009. The <br />proposed MLE revision to that system includes constructing four ponds. Two ponds <br />(EMP008a and EMP008b) will replace the previously proposed EMP008, but those <br />ponds will be located at higher elevations than was previous proposed. Pond EMP009 <br />will be constructed as originally planned in Poverty Gulch, but .will be smaller than <br />previously proposed and approved. The fourth pond on the west flank will be added to <br />the existing EMP007 series of ponds and will collect runoff from a larger area than was <br />previously planned because of the proposed Squaw Gulch Overburden Storage Area <br />Extension.(SGOSAE). <br />EMP ponds are primarily needed for the operations phase. Only ponds EMP007 and <br />EMP008b will have contributing watersheds after mining is completed. However, ponds <br />EMP008a and EMP009 will remain in place post-closure to serve as wildlife watering ponds. <br />• <br />