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2017 ANNUAL IMPOUNDMENT INSPECTION <br />Mine: New Horizon North Mine <br />Pond Name: Pond 001 <br />NPDES Permit & Outfall #s: CO -850062 <br />Date Inspected: 25 -October -2017 <br />Location Description: 2.4 miles NW of Nucla <br />Owner's Rep.: Frank Ferris, Mine Manager <br />Pond Type: Partly Incised <br />CDRM & S #: C-2010-089 <br />Date Last Inspected: 3 -March -2016 <br />Legal Location: Sec 25 of T47N R16W <br />Inspector's Name: Frank Ferris <br />Pond Capacity Data <br />As Built Pond Embankment elev.: 5680.0 As Built Pond Bottom elev.: 5665.0 <br />As Built Pond Emergency Spillway elev.: 5677.5 As Built Pond Primary Spillway elev.: 5675.5 <br />As Built Pond Capacity (pond bottom to primary spillway) per As Built 12.6 ac -ft <br />Existing Pond Capacity (pond bottom to primary spillway): As Built Volume - SV = 12.12 ac -ft <br />Sediment Volume (SV) at Inspection: 0.68 ac -ft, AutoCAD calculated — 2017 0.2 ac -ft removed <br />Surface Water elev. 5667.4 - Surveyed Pond Bottom elev. 5666.2 = Water Depth 1.2 <br />Water Volume (WV) in Pond 0.64 ac -ft (using as built capacity table & surface water elevation, and then <br />subtracting sediment volume under water level) <br />Pond Capacity Available below primary spillway 11.48 ac -ft [As Built Pond Capacity — WV — SV] <br />Inflow volume from 10 -yr 24 -hr storm runoff event 11.09 ac -ft <br />Note: 2.5 feet of sediment removed from east end, 2.5x100x35/27=325 cu -yds <br />Circle or Write appropriate Response <br />1. Seepage (specify location, color, and approx. volume) <br />2. Cracks or scarps on crest or slopes <br />3. <br />4. <br />5. <br />6. <br />7. <br />8. <br />9. <br />10. <br />Sloughing or bulging on slopes <br />Major erosion problems <br />Surface movements in valley bottom or on hillside <br />Water impounded against toe <br />Clogging <br />Yes lX <br />Yes IX <br />Yes N)( <br />Yes I` <br />JX Yes <br />Yes IX <br />a) Spillway channels and pipes Yes <br />b) Decant system Yes <br />C) Diversion Ditches Yes <br />Cracking or crushing of pipes <br />a) Spillway pipes Yes <br />b) Decant system Yes <br />Trash racks clear and in place YX <br />Monitoring instrumentation in place & functioning YX <br />JX <br />N/A <br />N/A <br />N/A <br />N/A <br />N/A <br />N/A <br />N/A <br />N/A <br />N/A <br />N/A <br />N)( N/A <br />No N/A <br />No N/A <br />Comments: Repaired erosion on southeast half culvert entrance & removed sediment in 2017. <br />M:\New Horizon North\Environmental\Pond Inspections & Examinations\2017_10 Annual Impoundment Inspections.doc <br />