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from approximate original contour (AOC) requirements or highwall reclamation requested or <br />approved in the East Pit, West Pit or Section 16 Pit. Exhibit 3 of the SL-04 application shows the <br />constructed post-mining cross-sections Exhibit 4 of the application shows the Gulch A Ditch as- <br />built profile (although the Division is not releasing this ditch, as described below). <br />Drainage reconstruction <br />The approved drainage reestablishment consisted of the design and construction of permanent <br />postmining drainage channels. The post-mine channels for the East Pit, West Pit and Section 16 <br />Pit are shown on Permit Map 41. Post-mine channels are designed and certified to safely convey <br />the peak discharge from the 10-year, 24-hour storm event in accordance with Rule 4.05.3. Certified <br />designs for the post-mine channels were approved prior to the bond release application and are <br />provided in Exhibit 7 of the permit. Exhibit 4 of the SL-04 application shows the completed <br />Gulch A Ditch as-built profile. <br />Phase II Bond Release <br />The Division evaluated Colowyo's request for Phase II bond release on 432.7 acres in the SL-04 <br />application, as shown on Figure 2 of this document. Under Colorado's Permanent Program, the <br />process of releasing the reclamation bond for a mine site is explained in Rule 3.03 and further <br />described in the Division's 1995 Guideline Regarding Selected Coal Mining Bond Release Issues. <br />The bond release process involves three phases. At Phase II, Rule 3.03.1(2) (b) states, "Up to <br />eighty-five percent of the applicable bond amount shall be released upon the establishment of <br />vegetation which supports the approved postmining land use and which meets the approved <br />success standard for cover... evaluation of vegetation establishment pursuant to this paragraph is <br />based on statistically valid data collected during a single year of the liability period." <br />Additionally, Rule 3.03.1(3) (b) states, "No more than sixty (60) percent of the bond shall be <br />released so long as the lands to which the release would be applicable are contributing suspended <br />solids to streamflow or runoff outside the permit area in excess of premining levels as <br />determined by baseline data or in excess of levels determined on adjacent nonmined areas..." <br />Evaluation and inspection of the reclaimed areas was based on the specific requirements of the <br />reclamation plan and the functional requirements of the post-mining land use. Criteria for bond <br />release included the following. <br />1. Topsoil replacement thickness <br />2. Vegetative cover and "bare areas" <br />3. Species composition will be visually evaluated, and should generally correspond to the same <br />date presented in the application <br />4. Erosional features <br />5. The condition of the sediment pond or ponds and any in need of maintenance <br />6. Construction and performance of permanent impoundments <br />Proposed Decision and Findings of Compliance 2 May 2011 <br />Partial Phase 1/II Bond Release SL-04 Page 5