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III. COMMENTS -COMPLIANCE <br />Below are comments on the inspection. The comments include discussion of observations made <br />during the inspection. Comments also describe any enforcement actions taken during the inspection <br />and the facts or evidence supporting the enforcement action. <br />to the mean, which is indicative of a normal data distribution with minimal skew. The DMG/OSM special focus <br />sample for the North Area consisted of 29 holes dug in various reclamation parcels throughout the area (see <br />Table 1, attached). The DMG/OSM sample was considerably smaller than the SCC sample. The sample was <br />obtained by digging holes in apparently representative topsoiled areas that were reasonably close to reclamation <br />roads accessible by vehicle. Sample parameters for the North Area were: <br />Sample Mean = 16.7" ............................................................... Sample Std. Dev. = 4.2" <br />Sample Median = 16.0" ............................................................ Sample Min. = 8.0" <br />Sample Max. = 26.0"* <br />The DMG/OSM range was narrower than the SCC sample, as would be expected due to the smaller sample <br />size. The lower mean, median, and maximum could quite likely be due to the fact that in the case of six of the <br />29 holes (dug with spade and sharpshooter shovel), the total thickness of the topsoil layer could not be <br />definitively determined (generally due to soil compaction or rock content at depth that made digging very <br />difficult). Regardless, the OSM/DMG sample indicated that a relatively uniform topsoil thickness had been <br />replaced on reclaimed portions of the North Area, with an average thickness that slightly exceeds the applicable <br />15.6" requirement. <br />There were similar disparities between operator data and DMG/OSM data for the topsoiled portions of the South <br />Area, but the reasons for the disparities are less readily apparent. SCC's sample for the South Area was based <br />on 29 holes on the systematic 1 per 5 acre grid, with a mean of 22.7, median of 22.0, standard deviation of 4.5; <br />range from 16 to 36. The DMG/OSM sample was based on 16 representative holes, with the following sample <br />parameters: <br />Sample Mean = 15.3" ............................................................... Sample Median = 14.5" <br />Sample Std. Dev. = 2.6" ............................................................ Sample Min. = 12.0„ <br />Sample Max. = 21.0" <br />Only one of the DMGIOSM holes did not penetrate the entire thickness of the replaced topsoil layer, so the <br />explanation for the significantly smaller sample mean and median as compared to the SCC sample is not clear. <br />Still, the inspection sample indicates that a relatively uniform topsoil thickness, which slightly exceeds the <br />applicable 13.2" requirement, has been replaced on reclaimed portions of the South Area. <br />During the inspection, an attempt was made to verify soil replacement thickness within the southern ridgeline <br />aspen reestablishment area. Results were inconclusive due to difficulty of digging holes in excess of 3 feet with <br />hand shovels, in relatively compacted clay loam soils with high density of large woody material. It is requested <br />that operator excavate one or more back-hoe soil pits in representative locations within each of the two <br />ridgeline pit aspen planting areas by the end of September 2006, and further requested that the operator <br />excavate similar pits within the aspen planting area to be established later this field season, upon <br />completion of topsoil application within the plot. The Division shall be contacted upon completion of <br />the pit excavations to allow for verification of replacement thickness within the aspen planting areas. <br />In conclusion, with the exception of the Ridgeline aspen establishment areas where replacement thickness could <br />not be determined, the DMG/OSM special focus investigation indicates that topsoil replacement was conducted <br />in conformance with applicable requirements. The operator will excavate soil pits within the aspen planting <br />areas to document soil replacement thickness in those locations later this field season. <br />Availability of Records <br />Required records were on file at the Seneca mine office, up-to-date through the 1s~ quarter, 2006 (see Records <br />Form attached). <br />4 <br />