2012-05-02_INSPECTION - C1981012 (2)

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May 1, 2012 C-1981- 012/New Elk Mine RDZ proposed outfall location is a 48" corrugated metal pipe (CMP) and in good condition. However, the culvert to the east (also a 48" CMP) is buried at the upstream end. The location where ditch D49 would originate was also inspected. The Division will need more details on the design of the upper end of this ditch to determine if it is sufficient to prevent flow down the drainage from impacting the proposed DWDA. Also, Al Weaver suggested that an access road will be needed for maintenance. The surface water monitoring point on the river (west and upstream of mining operations) was observed. NECC proposes that this point be moved upstream approximately 0.25 mile if the proposed project is constructed. It is likely that this monitoring point may need to be moved upstream even if the proposed project is not constructed, as this monitoring point is reportedly supposed to be the "upstream" monitoring point, yet is located downstream of areas already disturbed by NECC. Some of the ditches and culverts on Map 14 for TR -65 may be drawn incorrectly. Another culvert may be needed for ditch D54 to provide access to the Soil Storage Stockpile. It is unclear if culvert C51 provides a function or if it is in the correct location on the map. The ditches near the proposed Sediment Drying Area may be drawn incorrectly: ditch D34b should not be connected to ditch D52 and ditch D34a should likely be extended west to the road that accesses Containment 92. In subsequent submittals, these particular errors should be corrected and other drainage features checked by NECC and consultants for additional errors. Some additional ideas should be considered to protect the hydrologic balance. Diversion ditch D28 could be connected to ditch D31. This would route runoff from undisturbed land directly to the river rather than routing it to Containment 41, where it is co- mingled with runoff from disturbed areas. Also, it would be worthwhile to add a sediment sump below the Soil Storage Stockpile to prevent this resource from being transported down the valley. Regarding water monitoring, the following was discussed. Surface water monitoring below culvert C27 is not likely necessary as the area between this point and the upstream disturbance is long and highly vegetated. Thus, the likelihood of the transport of pollutants in runoff to this location is limited. ROADS — Rule 4.03: A water truck was observed spraying the road to the West Fan. The proposed roads on Map 14 in TR -65 require clarification. In particular, the roads needed to build the proposed DWDA and the Soil Storage Stockpile may have to be altered from the submitted map. It is unclear how these features will be constructed. Al Weaver suggested that a temporary road loop around the Soil Storage Stockpile is needed during the construction process of the pile. RECLAMATION SUCCESS - Rule 4.15, Rule 3: In the vicinity of the proposed DWDA, the water tank SAE above the Allen Mine access tunnel was found to be in Number of Partial Inspection this Fiscal Year: 10 Number of Complete Inspections this Fiscal Year: 3 Page 3 of 8