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and grade. The variations are primarily due to channels being field fit to the post mining <br />topography, and the channels are performing as designed. While the as-built channel profiles <br />measured on the ground matched the information provided in SL-3 Exhibit D, variations were <br />observed from the approved channel profiles provided in Exhibit 20-5.9 in both channel length <br />and grade. <br />In general, drainages are stable and well vegetated. Areas of erosion were observed during the <br />inspection; however for the most part, it was of a relatively minor nature and will not preclude <br />Phase I bond release. SCC will continue to maintain these channels as needed. There are, <br />however, two drainages that exhibited significant downcutting from recent events indicating that <br />surface drainage control has not been successfully completed, as required by Rule 3.03. General <br />observations of the drainages subject to this SL-3 bond release request are as follows; detailed <br />observations are in the bond release inspection report, and all of the channels are depicted on <br />Figures 2a and 2b of this document. <br />PM-l: There is a slight deviation in the approved design and the constructed channel, and there <br />are slight deviations in the measured channel profile in comparison to the as-built channel <br />profile. Minor erosion was observed in the channel bottom, there was side-cutting along the <br />north side of the channel at the top and some under-cutting of the Turf Reinforcement Mat <br />(TRM) in places. Erosion at the outfall of stock tank T-25 was repaired and armored with TRM <br />during the inspection. <br />PM-lA: The as-built channel is approximately 100 feet shorter than the designed channel. <br />There was some side-cutting along the north edge of the channel for its entire length and minor <br />erosion in the channel itself. There was some erosion at the inlet and outfall of the surge pond, <br />continuing to its intersection with PM-1. <br />PM-1B: The upper portion of the as-built channel is approximately 275 feet shorter than the <br />designed channel. The lower portion of the as-built channel is moved approximately 75 feet <br />west of its designed location and intercepts channel PM-1/PM-lA approximately 75 feet lower <br />than designed. With the exception of the lower 285 feet, which is up to ten feet lower in <br />elevation and subsequently steeper than the designed channel, the as-built channel profile is <br />constructed as designed. There was some side-cutting along the north side of the channel, some <br />erosion in the channel bottom, and some under-cutting of the TRM in places. <br />PM-1C: The as-built channel is approximately 125 feet longer than the designed channel, and <br />the as-built channel profile for the lower 300 feet of the channel is between 14 and 40 feet higher <br />than the design. This is a result of a slight variation in the post-mining topography and the <br />change in the alignment of the lower portion of the channel. The overall grade of the lower <br />portion of the channel is not affected. The channel is otherwise constructed as designed. The <br />channel was well vegetated and there were no erosional problems noted. <br />PM-2A: The as-built channel is generally between 25 and 150 feet west of the designed location <br />but generally follows the same path as the designed channel. The as-built channel is <br />approximately 165 feet shorter than design because it does not go up the slope as far as the <br />Page 12 of 22