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August 24, 2010 C-1981-019/Colowyo Coal Mine JRS <br />to flow into the Southeast Tributary to Streeter Ditch either on its own or from a series of contour ditches that <br />intercept the ditch. The Southeast Tributary to Streeter Ditch will be included in the Phase III Bond Release. <br />- The Southwest Tributary to Streeter Ditch conveys flow from west side of the Streeter watershed area of the East <br />Pit Phase III Bond Release area and discharges into the Streeter Gulch Ditch and ultimately the Streeter Pond. The <br />entire Southwest Tributary to Streeter Ditch is within the Phase III Bond Release area. The ditch was walked in its <br />entirety, from station 0+00 to station 34+57. Elevation readings were taken at locations along the ditch and <br />compared with the design profile shown on Map 33. The attached data and cross-section show that the elevation <br />of the ditch, as constructed, matches that of the design from Map 33. The ditch location was also compared with <br />the permitted location shown on Map 41 and the ditch was found to be constructed in the correct location. Finally, <br />the ditch construction was compared with the design requirements in Exhibit 7-14E. The approved designs call for <br />a ditch with a 10 foot bottom width, 3:1 side slopes, a depth of 2.6 feet and a vegetative lining. The on-the-ground <br />measurements showed that the ditch had a bottom width of approximately 20 feet, side slopes that were <br />approximately 3:1 and a depth ranging from approximately 3-5 feet. The bottom of the ditch was well vegetated <br />and there was some small rock that has washed into the ditch and has helped to protect it. In addition, the side <br />slopes of the ditch were armored with larger riprap. No problems were noted with side-cutting along the length of <br />the ditch and it appears as though the ditch has reached an equilibrium at this point. Water from the area was able <br />to flow into the Southeast Tributary to Streeter Ditch either on its own or through a series of contour ditches that <br />intercept the ditch. The Southeast Tributary to Streeter Ditch will be included in the Phase III Bond Release. <br />- In addition to the Gulch A Ditch, the Section 11 Ditch, the Southeast Tributary to Streeter Ditch and the <br />Southwest Tributary to Streeter Ditch, water from the Phase I, II and III Bond Release areas also flows into the <br />East Side Collection Ditch, the Streeter South Side Ditch and the Streeter Ditch. While these ditches were not <br />specifically walked on this inspection, they are walked in late spring/early summer each year. These ditches have <br />been found in good repair. These ditches convey flows from areas that are not included in the Phase 1, II and III <br />Bond Release areas and are not a part of the release. <br />- There is also a series of contour ditches in the reclaimed area that convey flow into the permanent, post-mining <br />ditches. The ditches are not located on any map but, rather, are field fitted as a part of the backfilling and grading <br />operations. They are grass-lined ditches which generally have less than a two foot bottom width and two foot <br />overall depth. These contour ditches are all permanent features that will be released with their respective areas. <br />West Pit Ditches and Drainage <br />- The portion of the West Pit that is included in the Phase I, II and III Bond Release is portions of the outslopes of <br />the West Pit Fill. The runoff from these areas is conveyed by a series of contour ditches into the East Taylor Pond <br />Ditch, the West Pit Coal Road Ditch or the West Pit Fill Ditch, and ultimately into the West Pit Pond. Both the <br />East Taylor Pond Ditch and the West Pit Coal Road Ditch intercept the West Pit Fill Ditch. While the three <br />ditches in the West Pit area are at least partially contained in the Phase I, II and III Bond Release area, all of the <br />ditches do and will convey flow from disturbed and reclaimed areas not included in the SL-04 and SL-05 <br />applications. As such, the East Taylor Pond Ditch, the West Pit Coal Road Ditch and the West Pit Fill Ditch <br />are being excluded from the Phase I, II and III Bond Release. <br />Section 16 Pit Ditches and Drainage <br />Number of Partial Inspection this Fiscal Year: 3 <br />Number of Complete Inspections this Fiscal Year: 0 <br />Page 8 of 39