_INSPECTION - C1981019 (47) - Laserfiche WebLink

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Colowyo C-1981-019 15 June 10 Pg 10/12 Topsoil: - During the inspection the Division dug five topsoil test holes in the Gulch A reclamation area. This is the area where Colowyo has applied for a Phase II Bond Release (Partial Phase 1/11 Bond Release SL-04, received on 1 June 2010). These five topsoil test holes are the first of approximately 20 the Division plans on digging in the East Pit Phase 11 Bond Release area to determine if Colowyo has met the required 18 inches of topsoil replacement. The following chart shows the hole ID, its location and the depth of the topsoil. The five test holes averaged 16.5 inches of topsoil. **See pictures at the end of this report.** Location Depth Northing Easting EP-TS-2010-01 16 4458030.603 261581.912 EP-TS-2010-02 16.5 4458199.139 261660.380 EP-TS-2010-03 12 4458418.810 261739.094 EP-TS-2010-004 19 4458531.834 261610.944 EP-TS-2010-05 19 4458254.792 261337.307 - Colowyo has started to replace the topsoil on the 2010 West Pit reclamation area. They have just started the replacement. Once all of the topsoil has been replaced on this area the Division will dig random test holes to verify that the topsoil was replaced in accordance with the approved reclamation plan. - The Division will be proposing a decision to approve Colowyo's Technical Revision 82, which is a variable topsoil replacement plan. The plan allows for more shallow topsoil replacement (approximately 6 inches) on ridges and steeper slopes. The topsoil depths will become gradually thicker down the slope to a maximum of up to several feet in the South Taylor Pit area. The revised topsoil replacement plan includes a detailed field verification and reporting plan. Prior to the variable topsoil replacement plan Colowyo had two different topsoil replacement plans. The first plan was to replace a minimum of 18 inches of topsoil. This plan was in place from the beginning of mining until 2005. In 2005 Colowyo conducted a new topsoil survey and found that they did not have enough topsoil to replace 18 inches on the remaining East Pit and West Pit reclamation. With the approval of Technical Revision 82 (approved on 29 May 2006) Colowyo will replace 8 inches of topsoil on reclaimed lands. The 8 inch topsoil replacement requirement applies to areas where topsoil was replaced from 2006 through 2009. - The Division requested that Colowyo heavily rip the area of the West Pit that was backfilled and graded in 2007. This area has gone through several freeze-thaw cycles and the backfilled area is very compact at this point. If Colowyo replaces topsoil on this area without first ripping it the topsoil could slide and there will be very poor to no root penetration. On the inspection the Division discussed this with Matt Guptill and he stated that Colowyo would rip this area. General Mine Plan Compliance: - The 101 dragline was back on the edge of the East Pit highwall. No additional reclamation has been completed on the East Pit highwall and Colowyo has shut off power to the 101 .