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Colowyo's approved reclamation plan was prepared in accordance with Rule 2.05.4. Colowyo's <br />topsoil replacement plan is contained in Permit Volume 1, Section 4.06 and on Map 28. Colowyo's <br />revegetation plan is contained in Permit Volume 1, Section 4.15. <br />Colowyo provided vegetation monitoring reports for the Phase II Bond Release areas in Exhibit 5 of <br />the SL-04 application. Colowyo also provided sediment loss data in part 4.0 of the SL-04 <br />application. <br />IV. OBSERVATIONS AND FINDINGS <br />The following discussion of observations and findings focuses on the results of backfilling and <br />grading work and drainage reestablishment in the East Pit, West Pit and Section 16 Pit for the <br />Partial Phase I Bond Release and the revegetation, topsoil replacement and soil loss demonstration <br />for the Partial Phase II Bond Release. <br />The evaluation of the bond release application included the bond release inspection, an office <br />review of the permit requirements and regulatory criteria and review of past inspection reports. The <br />bond release inspection was conducted on 24-27 August 2010. Several items including: the post- <br />mining topography, cross-sections of backfilled and graded areas, as-built drainage profiles, <br />topsoil replacement and revegetation success that were included in the bond release application <br />were reviewed by the Division in the office during the technical evaluation of the bond release <br />application before, during and after the inspection. <br />During the Phase I bond release inspection, participants walked through most of the bond release <br />request area to allow for visual assessment of compliance with pertinent requirements as <br />described above in Section III of this document. All of the data used to confirm the post-mining <br />topography and permanent, post-mining drainage channels was collected with a Trimble GeoXT <br />handheld GPS and Trimble Terrasync software. The data was analyzed with Trimble Pathfinder <br />Office 3.1, ESRI ArcMap 9.3 and Microsoft Excel 2007. The 24-27 August 2010 inspection <br />report details the findings from the inspection. A summary of the observations are discussed <br />below and the details are further discussed in the inspection report. <br />Backfdling & Grading <br />The Colowyo Mine has a variance from contemporaneous reclamation for backfilling and grading <br />work due to the nature of the multiple seam mining. All of the backfilling and regrading work <br />commences once the lower-most seam of coal has been extracted from a given pit. Observations <br />were made during the Phase I bond release inspection with regard to approximate original <br />contour and erosional stability of the reclaimed landscape. <br />The Division compared field data with the approved post-mining topography along Colowyo <br />cross-sections 1-1' and 2-2' in the East Pit. These cross-sections are shown on Exhibit 1 of the <br />SL-04 application and trend basically north-south. The Division also created an east-west <br />Proposed Decision and Findings of Compliance 2 May 2011 <br />Partial Phase 1/II Bond Release SL-04 Page 6