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CEC used the Revised /Universal soil Loss Equation (RUSLE) to demonstrate acceptable soil loss on the <br />reclaimed lands. The Division has previously approved CEC's use ofthis model to demonstrate acceptable <br />sediment solid demonstration. <br />PHASE III <br />Phase III bond release was not requested for SL 10. <br />III. OBSERVATIONS AND FINDINGS <br />PHASE II <br />Topsoil replacement thickness is 24 inches in the reclaimed B -Pit area. Parcels 31, 32, and 33 are all <br />within the B -Pit area. Parcel 31 was graded, topsoiled (topsanded) and seeded in the fall of 2009. <br />Parcels 32 and 33 were regraded, topsoiled and seeded in the fall of 2015. CEC's topsoil replacement <br />has been documented by CEC and verified by the Division during previous inspections. During <br />reclamation activities, CEC placed a post with the soil laydown thicknesses marked on the post. <br />Verification of the topsoil laydown consisted of photographing the topsoil thickness against the <br />markings on the post. CEC maintains a notebook with photos, dates and location of the topsoil <br />laydown. <br />Bond Release Inspection topsoil (topsand) verification holes within the bond release block were dug <br />with a power auger until a color and texture change was encountered. Topsoil/topsand hole <br />verification locations were randomly determined in the field. Ben Moline and Danny Kipp operated <br />the auger. If a color and texture change was reached, this depth was measured on the auger blade. <br />Due to the sandy nature of the topsoil (topsand) measuring into the hole was unsuccessful. <br />One hole was dug in each of the three parcels. Topsoil verification hole locations were randomly <br />determined by the inspector. Topsoil hole No. l was dug in parcel 33. Depth to color and texture <br />change =1.7 ft. Topsoil hole No. 2 was dug in parcel 32. The auger dug down to 2 ft. + with no color <br />or texture change of the topsoil. Topsoil hole No. 3 was dug on the south edge of Parcel 31. The <br />auger dug to 2 ft. + with no color or texture change. The topsoil/topsand on all three holes was the <br />yellow `B" horizon soil approved to be used as the top dressing. The Division finds that the topsoil <br />has been replaced as required by the permit commitments. Although the location that topsoil hole 91, <br />in parcel 33, was shy of the 2.0 ft. thickness, confirmation with the operator's verification photos <br />demonstrated that the operator applied the appropriate topsoil/topsand thickness in this parcel. Some <br />variability is topsoil laydown is anticipated. The Division finds topsoil/topsand laydown thickness in <br />all three parcels acceptable. <br />CEC uses a predictive equation to demonstrate vegetation success on the reclaimed areas. The equation <br />was derived from over ten years of monitoring data from the previously approved Osgood Sand <br />Reference area, and precipitations data. The predictive equation allows for variability experienced with <br />precipitation inconsistencies. The approved vegetation success equations are found in Section 2.05.4 <br />of the permit. <br />Keenesburg Mine C1981-028 SL -10 Page 5 of 9 <br />