2014-01-02_GENERAL DOCUMENTS - C1981010

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Bond Release Maps. These maps can overlay each other allowing for a visual comparison of the topography. The Division then placed transects through the reclamation parcels to be evaluated. Along each transect, sample points were placed where the transect intersects the contour lines on the PMT map. The elevation of each of these points was interpolated from the PMT maps and the SL -15 maps. During the ground inspection, the Division walked each of these transects and logged the elevation at each sample point using a Trimble YUMA GPS unit. Many variables effect the precision of the elevations measured with the GPS unit, however the error in elevation is generally consistent throughout the site. A surveyed elevation point is located near the water tanks adjacent to the mine office. The elevation at this point was measured with the YUMA GPS unit and the difference of that measurement from the know elevation is used as a correction factor. Using Microsoft Excel®, the Division charted the PMT map elevations, SL -15 map elevation and the on- the - ground measured elevation to create cross - sections from the transects for each reclamation parcel for an easy comparison. The detailed results of this analysis for each of the bond release parcels can be viewed in the October 24th, 2013 inspection report. Overall, it appears the bond release parcels have been backfilled and graded in accordance with the approved reclamation plan and the approved post mining topography. The grade and slope of the reclaimed parcels were comparable to the approved post mining topography. The highwalls have been reclaimed. Some rills and gullies were observed in the bond release parcels however significant erosional features and signs of instability were not observed during the bond release inspection. As vegetation established throughout the reclaimed parcels the amount of rills and gullies diminish. Large swales and depressions were not observed during the inspection of the bond release parcels. The graded parcels blend into adjacent regarded land. Each of these parcels drains into a reconstructed channel which discharges into a system of sediment ponds. See the Drainage Reconstruction section below for more details. Horse Gulch Fill Parcel K -A -13 encompasses a portion of the Horse Gulch fill. Based on the analysis discussed above, it appears these parcels have been graded in accordance with the approved post mine topography. Appendix T of the permit includes the design of the fill. The fill is inspected by a qualified engineer every quarter. TMI has been submitting these quarterly fill inspection reports since construction on the fill began and significant stability and erosional features have not been identified. The under -drain was constructed and completed and certified during the first quarter of 2010. Based on the field inspections and engineer certifications provided as quarterly monitoring reports for the fill, the Horse Gulch Fill has been constructed as designed. Drainage Reconstruction In general, each of the SL -15 bond release parcels have a northeast or a northwest aspect and positive drainage is established. Runoff from each parcel flows into drainage channels and then into sedimentation ponds prior to water discharging from the site. Major reconstructed channels are not included within the bond release block. A portion of a small tributary to Oak Gulch drainage is located within Parcel Z -A -13. This area appeared functional and stable at the time of the inspection. Summary and Conclusions Based upon a review of the mine permit, TMI's bond release application, engineer certifications for the Horse Gulch fill and site inspections, the Division finds that Trapper Mining, Inc. has completed regrading Trapper Mine Page 7 January 2014 SL -15 Phase I Bond Release