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Settling of the portal decline fill in the vicinity of the lower segment of the permanent channel has resulted in a lowering of the original backfill contours, and creation of a shallow depression in the channel which pools water when the channel flows. Over time, the depression will fill in with sediment, but in the interim the settlement has resulted in the creation of a small wetland area, with no evident negative ramifications to channel stability. Permit Exhibit 21 channel design specifies a steep channel segment (7.5%) and a low gradient channel segment (2.5%) with design parameters for each segment. The original channel construction was certified by Larry Reschke of Powderhorn Coal Company in 1995 (subsequent to the settling), and a segment reconstructed in 2000 in association with Ute Water Line installation, was certified by Jim Stover, P.E. consultant to SCC, in July, 2001. Representative channel bottom widths of 35' and 38' were measured during a joint DMG/OSM inspection in August 2001(Inspection Report dated 9/28/01), with representative depths of 34", 36" and 38" (including berm height), and 22" and 27" (not including berm height). Required bottom width is 35', with depth of 24". The low gradient channel segment of the Ute Water reconstruction reach was estimated using an abney level to be approximately 5%. Jim Stover's surveyed grade for the segment was 3.2%. Given the relative precision to be expected with an abney, the surveyed grade is considered reasonable. This compares to design gradient of 2.5%. In his certification, Mr. Stover included a table relating flow depth to velocity, showing that the design ramifications of the discrepancy between the design specification and the surveyed gradient were insignificant. The high gradient segment of the channel, immediately downstream from the Ute Water reconstruction reach, was estimated with the abney level to be approximately 8%, which is comparable to the design specification of 7.5%. The channel has functioned well since original construction in 1992, with no significant erosion and no instances of storm flow escaping the channel. During the field inspection in August 2001, it could not be discerned from visual observation whether the upper segment of the North Decline permanent channel would meet design depth requirement of 24", without reliance on existing channel berms for additional capacity. Measurements were taken using a hand level and measuring tape at two locations where depth appeared questionable (if berms excluded). Depths of 27" and 22" were recorded. The precision of the measurement is questionable, given the uneven riprap channel bottom. Calculated flow depth for the design storm event and corresponding channel gradient is 18" (Permit Appendix 13-2, p. NDEC-12). Based on the August 2001 observations and measurements, the Division requested the operator to modify the postmine topography map to specify modification or elimination of the berms adjacent to the permanent channel. The reason for the request was to ensure that runoff from upland areas would be able to enter the channel, following removal of temporary diversion and collection structures. The map was properly modified to specify the installation of berm breaks. The Division further requested that the operator submit an updated permanent channel P.E. construction certification, clarifying that the permanent channel will contain the design flow without reliance on berms (to ensure the long term functionality of the channel). An appropriate P.E. certification addendum dated 6/2/03 was prepared by Jim Stover and submitted to the Division. The addendum certifies that the channel has adequate capacity to pass the design flow with the required 6" of freeboard, without reliance on berms. The North Decline reclaimed areas on either side of the channel are stable, and relatively flat, appear to be similar to the original land form, and blend into the adjacent terrain, with no erosion evident. Based on the documentation provided in the bond release application regarding the reclaimed configuration and reconstructed channel, the referenced 2001 DMG channel measurements, and observations made during the May 2003 bond release inspection, the Divisions finds that backfilling and grading operations have been satisfactorily completed within the North Decline area. 2 West Portals The amended 2-West Portals Map in the revised bond release application appropriately delineates the "Graded, Seeded, and Mulched 2000" and "Graded, Seeded and Mulched 2001" areas which are subject to the requested bond release. The two portals, and associated overburden stockpile site were reclaimed in 2000; the compressor and substation facility, its associated overburden stockpile, and the overhead Phase I Bond Release 1 ] August 15, 2003