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mine. Thus, during the June 3, 2010 bond release inspection, topsoil thicknesses were spot- <br />checked using a sharpshooter shovel. In Mining Area No. 1, 12 holes were dug; the topsoil <br />ranged from 5 to 13 inches in thickness, with an average of 9.1 inches (10 inches required). <br />Six holes were dug in Mining Area No. 3; thicknesses ranged from 7 to 16 inches, and <br />averaged 12.5 inches (16.4 inches required). <br />Honeywood's November 19, 2010 response observes that the field depth measurements <br />provide only a snapshot of topsoil replacement, and that a more exact determination would <br />require a systematic and representative sampling plan. In addition, baseline soil depth <br />surveys are not able to determine exact topsoil salvage volumes. <br />In Mining Area No. 3, disturbance was limited to a small portion of the permitted area. The <br />Division had requested that Honeywood reevaluate the topsoil resource available for this <br />smaller disturbed area. Honeywood responded that 14 inches is a reasonable estimate of the <br />available topsoil, and that the 12.5 inches measured is an adequate replacement soil <br />thickness, given the limitations of the methods used. <br />The entire amount of topsoil salvaged from Mining Area Nos. 1 and 3 appears to have been <br />replaced during reclamation of the mined areas. Topsoil stockpiles that remain within the <br />permit area were derived of topsoil salvaged for construction of haul roads or ponds. <br />Therefore, the Division concludes that the replaced thicknesses accurately reflect the volume <br />of topsoil available from the mined areas prior to disturbance. <br />B. Revegetation <br />All reclaimed areas requested for bond release had an equal chance of being sampled. <br />The operator conducted vegetation sampling as agreed upon in a memo dated July 21, <br />2010. Sampling was conducted on a systematic grid rotated 30 degrees west to minimize <br />bias due to the seeding pattern. All reclaimed areas requested for bond release were <br />included within the area overlaid with the sampling grid. Two small areas, north of pond <br />B, and south of pond B, of Mine Area 1 (Map 2) did not have any cover transects fall <br />within their boundaries due to the small size of these areas. Visual inspection by <br />Division personnel during the bond release inspection, June 3, 2010, and regular I&E <br />program found adequate cover establishment on these two areas. <br />The reclaimed areas were grouped into two parcels; Mine Area 1 (73.1 acres), and Mine <br />Area 3 (9.9 acres), based upon the mining and reclamation sequence (Map 2 and Map 3 <br />of the bond release application). Reclamation cover success is based upon comparison of <br />the weighted averages from three reference areas; Grassland reference, Sagebrush <br />reference A, and Sagebrush reference B. Weighted comparisons are based upon <br />composition of the respective pre-disturbance plant community. Mine Area 1 parcel was <br />compared to a weighted mean of Sage reference A (89%) and Grassland (11 %). Mine <br />Area 3 parcel was compared to a weighted mean of Sage reference A (50%) and Sage <br />reference B (50%). Both reclamation parcels and all three reference areas were sampled <br />to statistical adequacy for Phase II Bond Release data. <br />5