_INSPECTION - C1992080 (24) - Laserfiche WebLink

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debris and sediment has been washed into the channel,but the culverts contained little sediment,indicating no recent significant flow through the culverts. Sediment control The vegetative cover established on the disturbed areas of the Carbon Junction Mine appears to be effectively controlling erosion. No significant gullies or sediment fans were found on the site. Erosion on the disturbed areas of the site appears to be occurring at a rate similar to adjoining undisturbed lands. The base of the North Pit reclaimed slope is contoured to act as a grass filter for trapping sediment in runoff coming off of the slope where the south half of the North Pit was approved as a small area exemption in TR-14. This grass filter terrace was in good condition. Backfilling and Grading Backfilling, grading, topsoil replacement, and revegetation appeared to have been completed in all areas within the permit area except topsoil stockpiles 4 and 7, and boreholes 17-1, 94-1, and 95-1 (the low areas where collection ditches have been regraded in the area of the gravel pit/coal permit boundary is being researched). Support Facilities No problems were found in the Equipment Storage Area at the south end of the permit area. Equipment previously stored there was removed from the site in 2008. Topsoil Stockpiles 4 and 7 were well-vegetated, were not gullied, and do not have weed problems. Topsoil replacement depths in the SL-4 bond release area were previously verified during the June 2008 inspection in the Equipment Storage Area and in the Permanently Reclaimed Spoil Area. Topsoil stockpile depths for the recently regraded areas (Pond 1, Pond 2, and collection ditches) were verified during the current inspection using a shovel at numerous locations. All locations had more than one foot of topsoil, consistent with the approved reclamation plan. Replaced topsoil depths in the North Pit area were observed during topsoil replacement in 2006 and were found to have more than the one-foot required thickness. Revegetation The areas that were recently backfilled, graded, and topsoiled (ponds and collection ditches) did not appear to have been seeded. The areas that were backfilled, graded, topsoiled, seeded, and mulched in summer 2006 had initially developed a nurse crop of sterile wheat/oat hybrid, a product called Regreen. During inspections in 2008 this nurse crop was reported as having given way to a good cover of wheat, orchard, brome, and rye grasses. Revegetated areas appear to have weathered the 2008-9 winter well, with grasses during this March 2009 inspection beginning to show the first signs of green. Reclamation Success As mentioned in the October 2008 inspection report, leaving topsoil stockpiles 4 and 7 as permanent features on the site would require a Technical Revision to the permit application that demonstrates each stockpiled topsoil is not needed for a plant growth medium and each stockpile meets approximate original contour. 5