2011-05-09_INSPECTION - C1981020

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May 2, 2011 C- 1981 - 020 /Munger Canyon Mine MPB instability were noted during this inspection. The reclaimed mine portals were inspected and were found to be stable with no cracks or other signs of erosion or instability. In 2008 a crack and slump had opened at one of the portal entries on the mine bench area. In September, 2009 J. E. Stover & Associates and CAM Mining repaired the portal by spraying Versa Foam System 15 into the portal void and backfilling with twelve inches of dirt and rock. The portal repair was successful and the entire portal area has remained stable and is in good condition (see Photograph No. 1). 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: East Salt Creek was flowing with turbid water due to snow melt runoff Munger Creek had no flowing water and was only damp in some locations. Ditches and culverts associated with the reclaimed waste disposal site, cover soil stockpile site, and both topsoil stockpile locations were in good condition and well maintained. The waste disposal area sediment pond was dry (see attached Photograph No. 2). The inlet area, embankment, and discharge structures were stable. The coverfill stockpile and the waste disposal site are shown in attached Photograph No. 3. The entire portal bench access road was inspected. We began the ascent up to the backfilled portals by walking along the drainage bottom that is tributary to Munger Creek and accessed the portals area by climbing up the steep slope at the head of the canyon. Photograph No. 4 is a view of the reclaimed portal access from the drainage below and shows that the reclamation has remained very stable with no signs of erosion or sloughing into the canyon below. Reclamation was completed on the former portal bench access road in 2007. Overall the reclamation looks very good and there has been minimal erosion since the reclamation was completed. All of the permanent drainage channels were inspected. They appear to have held up very well and are functioning as intended. Pennanent Drainage Channel H is shown in Photograph No. 5 and Channels E and F are shown in the attached Photograph No. 6. Several silt fence locations were identified as no longer functional due to sediment load or needing repair or replacement. The silt fences that are damaged or require maintenance are located at the toe of the former mine bench area and along Channel H (see Photographs 7 and 8). These silt fences may no longer be necessary since the entire disturbed area has been revegetated and stabilized and the last seeding was more than two years ago. CAM is required to maintain these treatment facilities until removal is authorized by the Division. Please repair or replace the damaged silt fences, or provide a demonstration through an appropriate technical revision that disturbed area sediment controls are no longer necessary. ROADS — Rule 4.03 Construction 4.03.1(3)/4.03.2(3) Drainage 4.03.1(4)/4.03.2(4) Surfacing and Maintenance4.03.1(5) and (6)/4.03.2(5) and (6) Reclamation 4.03.1(7)/4.03.2(7): Number of Partial Inspection this Fiscal Year: 7 Number of Complete Inspections this Fiscal Year: 4 Page 3 of 10