2015-09-01_INSPECTION - C1996084

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August 21, 2015 C-1996-084/Lorencito Canyon Mine LDS Inspection Topic Summary NOTE: Y=Inspected N=Not Inspected R=Comments Noted V=Violation Issued NA Not Applicable NA - Air Resource Protection N - Availability of Records NA - Backfill & Grading R - Excess Spoil and Dev. Waste NA - Explosives Y - Fish & Wildlife R - Hydrologic Balance Y - Gen. Compliance With Mine Plan N - Other NA - Processing Waste R - Roads Y - Reclamation Success R - Revegetation NA - Subsidence Y - Slides and Other Damage NA - Support Facilities On-site Y - Signs and Markers Y - Support Facilities Not On-site Y - Special Categories Of Mining Y -Topsoil COMMENTS This was a partial inspection by Leigh Simmons of the Colorado Division for Reclamation, Mining and Safety, (Division). The weather was clear and dry, although a very heavy rainstorm (-3in) occurred a week before the inspection. The site was generally in good condition, although maintenance will be required shortly in order to maintain continued compliance. EXCESS SPOIL and DEVELOPMENT WASTE — Rule 4.09 Placement; Drainage Control; Surface Stabilization: All three fills were in good condition. There were no signs of instability or erosion; the benches and slopes appeared to be well vegetated with a mixture of perennial grasses, annuals and shrubs. Arcadis are expected on site on Tuesday the first of September to sample vegetation in the drainages reporting to ponds 9A and 913, which would include fill 9. The down drains on fill 8 were in good condition. The repairs made to the slope east of the fill have been very effective and the previous erosion scars are barely discernable. The down drains on fill 7 were also in good condition, with no evidence of further damage, as was the contour ditch connecting it with fill 9. The down drain on the west side of fill 9 has obviously been damaged, although in the absence of any measurements it's not entirely clear how much of the damage was caused by the most recent storm. It's clear that the down drain continues to provide a preferential flow path for storm water, and that it has eroded to bedrock in many areas, so will not be cut much deeper. The outstanding question is whether or not the side of the down drain will adequately protect the fill material. NECC should evaluate the drain thoroughly. 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: All six ponds were holding water. Their embankments and spillways were in good condition. Number of Partial Inspection this Fiscal Year: 2 Number of Complete Inspections this Fiscal Year: 0 Page 2 of 23