2009-09-21_PERMIT FILE - C1980007A ‎(5)‎

• Permit No: C1980007A
• IBM Index Class Name: Permit File
• Doc Date: 9/21/2009
• Doc Name: Mine Water Control Plan
• Section_Exhibit Name: Exhibit 66 Mine Water Control Plan
• Media Type: D
• Archive: Yes

West Elk Mine - Mine Water Control Plan Mountain Coat Company
• TABLE OF CONTENTS
1.0 INTRODUCTION ..................................................................................................................1
1.1 Project Description .......................................................................... ..........................1
1.2 Analysis Methods ............................................................................ ..........................1
1.3 Design Criteria ................................................................................ ..........................1
2.0 SEDCAD+ INPUT PARAMETERS APPLICABLE TO ENTIRE PROJECT ..........................2
2.1 Storm Type ..................................................................................... ..........................2
2.2 Rainfall Depth .................................................................................. ..........................2
2.3 Structure Naming Convention ......................................................... ..........................2
3.0 SEDCAD+ INPUT PARAMETERS FOR SUBWATERSHEDS ................... ..........................3
3.1 Subwatershed Boundary ................................................................. ..........................3
3.2 Soil Type & Land Cover .................................................................. ..........................3
3.3 Subwatershed Hydrologic Parameters ............................................ ..........................4
3.3.1 Hydrologic Soil Group ................................................................... ............................. 4
3.3.2 Curve Number ............................................................................... .............................4
3.3.3 Time of Concentration ................................................................... .............................4
3.3.4 Muskingum Routing Parameters ................................................... .............................4
3.3.5 Hydrograph Response Shape ....................................................... .............................5
3.4 Subwatershed Sediment Parameters .............................................. .......................... 5
• 3.4.1 Soil Erodibility Factor, K ................................................................ .............................5
3.4.2 Length-Slope Factor, LS ............................................................... ............................. 5
3.4.3 Control Practice Factor, CP .......................................................... ............................. 5
3.4.4 Particle Size Distribution ............................................................... ............................. 6
4.0 SEDCAD+ INPUT PARAMETERS FOR STRUCTURES ......................................................7
4.1 Ditches ...................................................................................................................... 7
4.2 Culverts .....................................................................................................................7
4.3 Muskingum Routing ...................................................................................................7
4.4 Ponds ........................................................................................................................7
5.0 SEDCAD+ OUTPUT / RESULTS ......................................................................................... 8
5.1 Ponds ........................................................................................................................8
5.2 Subwatersheds ......................................................................................................... 8
5.3 Ditches and Culverts ................................................................................................. 8
5.4 Small Area Exceptions and Other Exemptions .......................................................... 8
APPENDIX A: OUTPUT SUMMARY TABLES
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