2015-06-25_INSPECTION - C1992080

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June 23, 2015 C-1992-080/Carbon Junction Mine MLT HYDROLOGIC BALANCE - Rule 4.05 Drainage Control 4.05.1, 4.05.2, 4.05.3; Siltation Structures 4.05.5, 4.05.6; Discharge Structures 4.05.7, 4.05.10; Diversions 4.05.4; Effluent Limits 4.05.2; Ground Water Monitoring 4.05.13; Surface Water Monitoring 4.05.13; Drainage Acid and Toxic Materials 4.05.8; Impoundments 4.05.6, 4.05.9; Stream Buffer Zones 4.05.18: • Precipitation records from a nearby CoCoRaHS (Community Collaborative Rain, Hail & Snow Network) station (No. CO -LP -B) indicate that 3.53 inches of rain fell in May, and an additional 1.95 inches have fallen thus far in June. Noteworthy dates and amounts include 0.44 inches on May 6th, 0.81 on May 17th, 0.71 on May 19th, 0.47 on June 6th, and 0.52 on June 11th. • The riprapped Carbon Junction Permanent Diversion and unnamed tributary, appear to have performed well this Spring. Sediment from the September 2014 storms filled-in between the boulders in flatter segments of the channel. The Upper Carbon Junction segment, below the North Pit, appears to be moving toward a steady-state condition. A defined channel is present along the middle of the drainage, with a well -vegetated "flood -plain" on either side. TOPSOIL Rule 4.06 Removal 4.06.2; Substitute Materials 4.06.4(4); Storage and Protection 4.06.3; Redistribution 4.06.4: Permanent topsoil stockpiles 94 and 47 were well -covered with vegetation, and no signs of erosion were observed. BACKFILL and GRADING Rule 4.14 Contemporaneous Reclamation 4.14.1; Approximate Original Contour 4.14.2; Highwall Elimination 4.14.1(2)0; Steep Slopes 4.14.2, 4.27; Handling of Acid and Toxic Materials 4.14.3; Stabilization of Rills and Gullies 4.14.6: The reclaimed North Pit slope continues to perform well. No signs of erosion or instability were observed. • The Permanently Reclaimed Spoil Area (PRSA) lies within the original Carbon Junction Channel. The top surface was well vegetated, and appeared to be stable. • No rills or gullies were found to be problematic. RECLAMATION SUCCESS - Rule 4.15, Rule 3: The reclamation overall seems to be successful. Under PR -01, a primary postmining land use of Dryland Pasture is proposed. A band of horses were sighted in the drainage to the north of the Carbon Junction Canyon, and their hoof prints were present throughout the reclaimed areas. RE VEGETATION Rule 4.15 Vegetative Cover; Timing: • Areas of the permit seeded in 2006 (North Pit, PRSA, South Pit Drill Pad, and Equipment Storage area) and in 2008 (Sediment Ponds and topsoil stockpiles) exhibited successful Number of Partial Inspection this Fiscal Year: 4 Number of Complete Inspections this Fiscal Year: 4 Page 3 of 10