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slope of the walls of the lower pit. The.ultimate shape of the lower pit area will <br />likely be an elongate narrow zone reflecting the last marble extraction pattern <br />with white marble exposed:at the bottom of the cut and gray marble or other rock <br />types exposed along the walls of the bottom pit. At the least, the bottom of the pit <br />will be covered with topsoil and seeded. In the event that the lowest pit azea <br />migrates north with marble extraction operation, the southern portions of the <br />lower pit (the lower pit area currently exposed) may be backfilled with waste rock <br />prior to topsoiling and re-vegetation. This may be performed as long as an <br />adequate azea of pit bottom remains available for receipt of in mine storm flows <br />during and after mining operations. if highwall development and adequate <br />footwall rock competency can be confirmed, the lower pit area may exceed the <br />current bottom elevation by a considerable amount, up to 100 feet lower than <br />currently exists. <br />y-~~.6!A revised reclamation map will be drawn to show final contour lines in more <br />detail than shown on the first submittal. <br />~~ ~,7'Eazly summer season water flows where minimal during 2006 due to low snow <br />conditions. During most of the summer of 2005, water flowed from two or three <br />locations directly above and within 350 feet from the existing disturbed highwall <br />zone on the west flank of Taylor BasirL These flow were less than 5 gpm or less <br />but persisted throughout most of June and July, 2005. It appeared that the flow <br />came from collapsed adit entrances that are now no more than depressions of rock <br />and soil. Remnant pipe, rail, wood and metal trash, and small log structures aze <br />alt that remain at the surface neaz the former underground working entrances. <br />The approximate location of these workings is marked on the Mine Plan Map Cb, <br />existing mine disturbance. <br />~As stated in mine plan narrative, water diverted to the lower pit infiltrates into <br />bedrock at a reasonably high rate. No standing water has been noted in the lower <br />pit throughout its history. Colorado Mazble does not consider this water/sediment <br />control structure to be anything more than a 72 hour or less holding structure that <br />allows storm run-off to percolate into bedrock ai a safe and reasonable rate. If at <br />any time in future, water diverted to the lower pit does not infiltrate into the <br />ground within 72 hours, arrangement will be made to release said waters directly <br />to Taylor Gulch. <br />In the event that a closed system wash plant is employed at the site, water will be <br />procured from a legal off site source and transported to the site for use. <br />50. The following responses to the Division's comments: <br />a. Please refer to the watershed map Gb showing the proposed affected ]and <br />boundary and the potential watershed azea totaling 390 acres. Of the <br />potential 390 acres that may impact the storm flow output in Taylor Gulch <br />at the point of lowest elevation in the affected land boundary, most of the <br />