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III. COMMENTS -COMPLIANCE Below are comments on the inspection. The comments include discussion of observations made during the inspection. Comments also describe any enforcement actions taken during the inspection and the facts or evidence supporting the enforcement action. Genera! Comments A complete inspection of the mine site and office records was conducted. In addition, a special focus joint OSM inspection was conducted with Henry Austin of OSM. The special focus topic was topsoil replacement. Weather was clear and very warm; site conditions were dry. April, May, and June precipitation has been below normal. Dennis Jones was present during my records check on 6/19 and accompanied me on inspection of Sage Creek sediment ponds on 6/22; Ray Karo was present during a portion of the special focus inspection and was briefed on the special focus findings. Reclamation operations using the dragline have been completed, and the dragline has been moved to a location at the intersection of "A" road and the Ridgeline Access Road for temporary storage. Pit backfill and rough grading operations will be continuing with dozers in the vicinity of the lower end of the final WC pit and adjacent lower end of the final 016 Gulch south Wadge Pit, and portions of the final 016 Gulch north Wadge Pit (upper and lower ends). Permanent channel repairs/riprap installation had recently been conducted on several South Area channels, and at the time of the inspection, riprap installation was in progress along Channel PM-1A in the 017 watershed. Topsoil replacement operations for the year had not yet been initiated. A small area along the upper end of the South leg Wadge Pit in the 016 watershed that had been topsoiled late last fall but not seeded, was seeded earlier this spring. Toosoil Reolacement Soecial Focus Topsoil salvage and replacement was the special focus topic for the oversight year. At Seneca II-W, on-going topsoil handling operations are limited to topsoil replacement; coal extraction ceased in January 2006, and topsoil salvage operations had been completed during the 2005 field season. SCC's scraper fleet was in use at the Yoast mine at the time of the oversight inspection; 2006 topsoil replacement operations had not yet been initiated at Seneca II-W. For these reasons, the special focus inspection involved evaluation of compliance with permit specified topsoil replacement thickness. Within the original permit area ("North Area') the specified average replacement thickness is 1.3 feet (15.6 inches). Within the South Extension revision area ("South Area"), the originally approved average replacement thickness was 1.6 feet, and the plan included multiple zones of variable thickness. Due to cessation of mining several years earlier than had been anticipated, and based on soil inventory completed in early 2005, SCC determined that the original topsoil replacement plan for the South Area would not be feasible. These determinations and the inventory results were presented to the Division prior to initiation of South Area topsoil replacement operations in 2005, and as a result, an amended topsoil replacement plan was developed for the South Area. The amended plan was included in Permit Revision No. 5 (PR-5); for which the Division issued a proposed approval decision on June 16, 2006. The PR-5 topsoil plan specifies an over-all average replacement thickness of 1.1 feet (13.2 inches) for the South Area. The plan also specifies a replacemenf thickness of 4 feet for the two Ridgeline Pit aspen reestablishment areas planted in 2005, and one remaining South Area Aspen planting area (to be topsoiled and planted in 2006). Finally, the plan specifies a 6 inch replacement thickness for South Area upland shrub establishment areas to be planted in 2006 or subsequently. SCC has conducted replacement thickness checks of varying intensity on an annual basis over the life of the mine, which have indicated that permit specified replacement thickness was being achieved. In anticipation of up-coming bond release demonstrations, SCC systematically sampled all areas of the mine that had been topsoiled through the end of the 2005 field season in the fall of 2005, using a one hole per five acre sample grid The sample results were presented in tables and map figures included in the 2005 annual reclamation report. SCC's systematic sample for the North Area consisted of 161 holes, with a mean topsoil thickness of 22.9 inches. Although the data showed a considerable range in thickness (minimum of 0 and maximum of 36"), the variance was relatively low (standard deviation of 7.4"), and mapping indicated no areas of significant extent in which the soil thickness was notably thicker or thinner than the average. Sample median (22.0") was quite close 3