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A 9860 9855 9850 9845 9840 9835 9830 A Storage-DepthStormwater r /,A MINERAL MOUNTAIN PROJECT Free Board 120g ft wide Vol = 9.300 cu ft 70k oal UNDERGROUND MINE TOTAL MINE P92MIT AREA 9.35 ACRES //„/,,,,//////,/,//////,///,////,/,///„/,/ HISTORICAL DISTURBANCE -4.4 ACRES SECTION A -ACROSS WORKING AREA AND STORMWATER STORAGE AREA (SECTION IS TYPICAL AND LOCATION WILL VARY) Exhibit Map E-2 Stormwater Runoff Cripple Creek Project Owner Address: Owner Phone Number: Mineral Mountain Gold, LLC 719-689-5965 P.O. Box 247 Cripple Creek, Colorado 80813 EXPLANATION Permit Boundary 9900 True North Contour (interval 5 feet) Magnetic North 9' Surface Water Flow Direction Mapped Pits, Adits and Shafts Feet 0 30 60 SCALE 1"=60' M-2014-045 AR01 Contour Interval = 5 feet ^ -^- ,.^w"1% .e r 90 PLOW DESIGN NECESSARY OF ACCESS ROAD SEP 16 Liu I DIVISION OF RECLAMATION Exhibit Map E -1A — Permit and Adjacent Area MINING AND SAFETY brawn BRAUN ENVIRONMENTAL, It 355 South Teller Street Ste 200 Lakewood, COLORADO 80228 PHONE (303) 988-7697 Mineral Mountain Gold, LLC Cripple Creek Project, Cripple Creek, Co November 19, 2014 Drawn by: Staff Date Rev: 8/2-87-15 Checked by: C.A. Braun ENGINEER'S CERTIFICATION This report was prepared by the Engineer who's signature appears below or the engineer's direct supervision). SIGNATURE: 4/ G��;/ !// ,r , No. 22601 DATE: SITE DESCRIPTION MINERAL MOUNTAIN PROJECT ACTIVITY UNDERGROUND MINE TOTAL MINE P92MIT AREA 9.35 ACRES TOTAL DISTURBED AREA HISTORICAL DISTURBANCE -4.4 ACRES NEW DISTURBANCE- LESS THAN 0.3 ACRES SCS RUNOFF CURVE VALUES (CND UNDISTURBEDAREA 442 DISTURBEDAREAS 52 CONCRETEROOF 98 DISCRIPTION OF DISTURBED AREAS ROAD SURFACES CONSIST OF POORLY GRADED MIXTURE OF ROCK UP TO 3 IN DEA. HISTORIC MINING DISTURBED SURFACES INCLUDE LEVELED AREAS AND WASTE ROCK PILES DESCRIPTION OF NONDISTURBED VEGETATION AREAS TIMBER COVERED WITH GRASSES AND SHRUBS MIXED IN LESS SHADED AREAS POTENTIAL POLLUTION SOURCES TO STORMWATE2 NO FOLUTION SOURCES - NO HAZARDOUS GEOLOGIC SUBSTANCES, NO OFflN CONTAINERS OR CHEMICALS STORED OUTSIDE LOCATION OF NO” I ORMWA I E DISCHARGE NO SOURCES KNOWN NAME AND LOCATION OF RECEMING WATERS DISCHARGE TO UNNAMED NORTFFTRINDING DRY GULCH -GULCH CONNECTS TO SPRING CREEK, AN INTERMITTENT STREAM A DISTANCE OF 2,200 FEET NORTHWEST OF THE PERMIT AREA. RESULTS OF CALCULATIONS MAXIMUM SURFACE FLOWS - 24 -HR 100 -YR EVENT NO DIVERSION POINTS NECESSSARY. ALTHOUGH NOT REQUIRED PER REGULATIONS, WORK SURFACE BERM HAD CAPABILITY OF RETAINING 300 PERCENT OF ENTIRE 10 -YEAR 24 STORM EVENT RUNOFF FROM DISTURBED GROUND ANDOVER 200 PERCENT OF 100 -YEAR 14 HOUR EVENT. DISCHARGES VIA RAPID INFILTRATION INTO WORK AREA SURFACE NEW PRECIPITATION WATER GENERATED BY OPERATION 2.47 INCHES PRECIPITATION PRODUCES MAXIMUM VOLUME OF 140 CUBIC FEET (NEN DISTURBANCE) (CN= 98) WITH NO FLOW BEYOND SURFACE SHEET FLOW WITHIN CONTAINED AREA FOR (BUILDINGS AND CONCRETE SURFACES ASSOC WITH 24-HOUR I0 -YEAR EVENT CURRENT OPERATION - 700 SQ FT TOTAL) VOLUME GENERATED .ON OLD DUMP —SURFACE - OLD 2.47 INCHES PRECIPITATION PRODUCES 2,700 CU FT FOR THE 10-Y EAR EV ENT DISTURBANCE (CURRENT WORK AREA) (CN = 52) TOTAL AREA - 22,000 SQ FT TOTAL CALCULATED STORM✓VATER GENERATED WITHIN 2,850 CU FT (SUM OF BUILDING RUNOFF PLUS HISTORIC GROUND SURFACE) CURRENT WORK AREA (10- YEAR STORM) RUN-OFF STORAGEAREA CAPACff1' 9,300 CU FT AT A DEPTH OF 18 IN (7,000 So FT TYPICAL) ANTICIPATED DEPTH OF FILL TO 6 INCH FOR 10 -YEAR EVENT FACTOR OF SAFETY OF 3 INCLUDES VOLUME FOR NEW RUNOFF ASSOCIATED WITH PERMITTEDOPERATION PLUS RUNOFF FOR HISTORIC DISTURBANCE DESIGN DETAILS I. bORMWA I ER CONTAINMENT AREA TO CONSIST OF GENTLY SLOPING DEPRESSION MAINTA INED WITHIN THE WORKING AREA DESIGNED TO CONTAIN THE CALCULATED VOLUME GENERATED BY RUNOFF FROM THE 10-Y FAR STORM EVENT. BOTTOM AND SIDES ARE SUCH TO ALLOW COLLECTED STORWVATER TO BE RELEASED VIA INFILTRATION. BERM SPECIFICATIONS INCLUDE HEIGHT OF 2.0 FEET ANDA WIDTH OF NO LESS THAN 2.0 FEET AT A DISTANCE OF 1.5 FEET BB -OW THE CREST. THE BERM IS TO BE LOADER- PLACED AND COMPACTED AND SHALL BE COMPOSED OF POORLY SORTED NATIVE MATERIALS SIZED FROM CLAY TO MINUS 4 INCHES. THE STORAGE AREA SHALL BE SUCH THAT A FREE BOARD OF 1.0 FEET WILL BE MAINTAINED. CONTAINMENT IS RECOMMENDED BUT NOT REQUIRED BY REGULATION AT THIS TIME HOWEVER, IF ACID GENERATING ROCK SHOULD BE STORED ON SURFACE STORE MVATER RETENTION SHALL BE MANDATORY. 2. NO RUN-ON DIVERSIONS ARE NECESSARY, AS TOTAL DISTURBED AREA IS SO SMALL. UPGRADIENT SEDIMENTATION AREAS AND DIVERSIONS IN THE FORM OF ROADS AND TRAILS ARE ALREADY NPLACE CONSTRUCTION OF ADDITIONAL STRUCTURES WOULD ADD LITTLE INCREASE IN PROTECTION AND ONLY INCREASE AREA OF DISTURBANCE THE MAIN ACCESS ROA D SERVES AS A DIVERSON FOR TOPOGRAPHICALLY UPGRADIENT SHEETFLOW WATERS GENERATED TO THE SOUTH AND DIVERTS THEM TO EASE NO OTHER RETENTION PONDS, LINED OR UNLINED CHANNELS, OR OTHER RUN-ON AND RUN-OFF CONTROLS, OR OUTLET CHANNELS ARE NECESSARY FOR THIS SITE AS ANY COLLECTED SURFACE WATERS ASSOCIATED WITH THE NEW DISTURBANCES ARE DISSIPATED VIA INFILTRATION. 3. PERMANENT OR TEMPORARY SOIL STABILIZATION MEASURES SHALL BEAPPLIED TO NEWLY DISTURBED AREAS NO LONGER TO BE USED WITHIN 30- DAYS AFTER USE HAS CEASED. ITIS RECOMMENDED THAT PERMANENT S® MV IS TO BE APPLIED NO EARLIER IN THE YEAR THAN NOVEMBER AND NO LATER THAN MAY TO MAXIMIZE GERNINATION OF SEED. THE APPROVED MIX SHALL BE APPLIED AT RATES RECOMMENDED BY THE ENGINEER AND S® VENDORS. 4 A SEDIMENT DISSIPATION AREA IS TO BE LOCATED DOWNGRADIFNT OF THE WORKING SURFACE AND SERVE ASA BACKUP FOR FOR SEDIMENTOONTROL THE DESIGN CONSISTS OF A NEAR -LEVE- ROAD SURFACE TO COLLECT SEDIMENTS. ALL CONTROLS, ARE TO BE MAINTAINED FOR THE LIFE OF THE PROJECT. 5. AREAS WHERE FINE GRAINED SOILS ARE SUBJECT TO EROSION SHALL BE PROTECTED USING SILT FENCE PLANTEDGRASSES, CRIMPED MULCH, OR OTHER SUITABLE MEANS.