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• Data points in smaller areas where there are no cross sections or drainages (e.g., EP055, <br />WP012 /013) <br />• Data points at small ponds (a.k.a. stock tanks) in the East Pit. <br />The GPS data collected during the inspection were compared to the as -built topography provided <br />in the SL -06 application and the approved channel designs (Maps 33 and 33A in the PAP). All <br />of the measured elevations along the cross - sections and in the channels were within <br />approximately 10 feet of the as -built elevations shown on SL -06 Exhibit 1, Map 33 in the PAP, <br />and Map 33A in the PAP, with the majority of the measured elevations being +/- 5 feet. The <br />Division finds that Colowyo has reconstructed the topography in the SL -06 area as approved. <br />An area of hummocks was observed in reclamation block EP046; the area is approximately half <br />an acre (measured with GPS during the inspection). This area is well vegetated and appear <br />stable, and the Division does not believe that this small area warrants an exemption or further <br />action. <br />For both the East Pit area and the West Pit area, the Division finds that the Colowyo Mine has <br />achieved a post- mining surface that conforms to the approved post- mining topography and <br />resembles the general surface configuration of the land prior to mining. All highwalls have been <br />eliminated and the reclaimed lands blend in well with the adjacent undisturbed slopes. No <br />erosion problems were noted in the Phase I Bond Release areas, and no settling, slumping or <br />cracking of the backfill was observed. <br />Drainage Control <br />The Division inspected the permanent, post- mining drainage channels in the Phase I Bond <br />Release areas of the East Pit and West Pit. However, only a portion of these drainage channels <br />are being released as part of the SL -06 decision. The channels in the West Pit area — namely <br />Taylor Tributary Ditch, Taylor Ditch, and East Taylor Ditch — are not being released with SL -06; <br />the reason these drainages are not being included is because they still receive runoff (or in the <br />future will receive runoff) from large disturbed areas that have not been released. <br />The following ditches were inspected: Final East Pit, North Tributary East Pit, Prospect, East <br />Taylor, Taylor, and Taylor Tributary. Based on spot checks with a measuring tape and <br />clinometer and based on general observations, most reaches of the ditches met the specifications <br />in the PAP (Table 1 in Exhibit 7, Item 14) in terms of bottom width, depth, side slopes, and <br />riprap size. Also, the transitions were in the correct locations for the ditches with some reaches <br />with riprap and some reaches without riprap per design (e.g., East Taylor Ditch). <br />East Taylor Ditch has been recently reconstructed after a thunderstorm caused severe erosion; it <br />appeared that the construction was performed well in terms of the parameters listed above. <br />Proposed Decision and Findings of Compliance April 2013 <br />Partial Phase I Bond Release SL -06 Page6 <br />