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• 1 recommend that we immediately begin a dialogue with Colowyo to bring on-the- <br />ground conditions into reasonable compliance with hydrologic design assumptions. <br />As a result of the meeting on-site with Colowyo, we agreed that the following information was <br />necessary (stated below in quotes from J. Stark meeting follow-up memo of March 7, 2008). <br />"The Division has asked Colowyo to provide a more detailed description and timing of <br />the final regrading and closure of the East Pit, including a map, or plate, and acreages <br />of each regraded area, to ensure that it will conform with the approved design and the <br />SEDCAD modeling. Additionally, the Division has also requested that Colowyo <br />provide a more detailed description of any alternate sediment control measures that it <br />will use in the East Pit reclamation. This information will allow the Division to more <br />accurately assess the East Pit reclamation and give the Division a higher level of <br />confidence with regards to the Prospect drainage and the Prospect Pond." <br />Current modeling of the Prospect watershed includes ONLY disturbed acres, that in the worst <br />hydrologic condition, are topsoiled and seeded. In other words, modeling includes no areas <br />of regraded spoil or spoil. This is significant for the following reason. Colowyo regraded 86 <br />acres in 2006 and topsoiled those same acres in 2007. They completed no backfilling and <br />grading to final grade in 2007 in the East Pit (see 2007 ARR). Therefore, to maintain any <br />semblance to the current modeling and pond design, Colowyo must topsoil and seed all <br />acres backfilled and graded in the same field season. Whether this is logistically feasible is <br />unknown at this time. There are about 281 acres remaining in the Prospect watershed to <br />return to final grade, topsoil, and seed. <br />Furthermore, Colowyo is currently sumping runoff from reclaimed areas to the pit or partial pit <br />as the case may be. This obviously helps prevent issues at the Prospect pond and beyond <br />but also raises questions about design criteria, maintenance, and impoundment questions <br />relative to the ditch and sump. This is a programmatic issue to some extent and we may <br />need a supervisor to make the call on this practice. If we have no design information for a <br />ditch/sump system that fails, we have no way to ensure that the system is maintained to any <br />required standard or design. <br />Hopefully, the information submitted by Colowyo regarding timing, reclamation, and <br />alternative sediment control will be sufficient to resolve this situation. <br />The Division anticipates significant surface water, sedimentology, and reclamation <br />timetable details to be submitted by Colowyo in the near future for the East Pit area. <br />Let me know if you have any questions. <br />