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Description of the Operation and Reclamation Plans <br />Since the last permit review, several revisions to the original permit have <br />taken place. Of significant importance is the termination of all coal mining <br />activities on the site as of December 1987. The Keenesburg site is now mainly <br />a fly ash disposal facility for the Coors power plant in Golden. Fly ash <br />disposal was approved by the Division through Technical Revision 13 and began <br />in October, 1987. All stockpiled coal has been removed form the site. Mining <br />methods previously used at the site are not listed here but can be found in <br />the November 1986 findings document and in Section 2.05.3 of the permit <br />application. <br />The topsoil management plan was altered by the approval of Technical Revision <br />16. TR-16 allowed topsoil replacement depths on Pits A and B to be altered <br />from three feet to a minimum of two feet to allow for sufficient topsoil <br />coverage of six inches over the facilities area. Temporary access roads will <br />have a two foot top sand cover with fifteen inches cover on the long-term <br />spoil areas. Topsoil salvage depth was also altered, from six to four feet <br />due to current amounts available on the site. No topsoil salvaging has taken <br />place since 1989. <br />TR-16 clarified the revegetation criteria used in reclamation of both Pits A <br />and B. The seed mix was altered to include more warm season species. In <br />addition, total vegetative cover and species success criteria were established <br />for the site. Methodology was clarified and a detailed annual vegetative <br />monitoring plan submitted. Of the 424 disturbed acres at the mine site, 133 <br />have been seeded since 1985. No revegetation has taken place since 1989 and <br />no additional disturbance has occurred since 1987. <br />The fly ash disposed of at the site originates from the Coor's Power Plant in <br />Golden and consists of residue from 807< Colowyo, 107 MacIntyre stockpile and <br />107 Keenesburg stockpile coal. During 1990, the third year in ash disposal <br />operations, a total of 32,451 tons of mixed fly and bottom ash was dumped in A <br />pit (east end) and in 1991 a total of 23,511 tons of fly ash was buried. Mass <br />balance calculations estimate that ash disposal can continue in Pit A for <br />another five years at present disposal rates. Filling of Pit B continues with <br />the deepest part (north end) to be filled in the near future. The fly ash is <br />deposited in both A and B pits at a depth no less than five feet above the <br />projected post mine ground water table and at a minimal depth of eight feet <br />below the original ground surface. <br />Spoil will be replaced in pits. Excess spoils will be leveled to present a <br />surface contour similar to the pre-mining surface. The spoil ridges will be <br />reclaimed to a very low rolling topography prior to topsanding. The spoil <br />will be ripped or scarified on contour. Top sand averaging 24" in depth will <br />then be placed on the leveled spoils. The final highwall will be backfilled <br />to AOC. The surface drainage pattern will be reestablished. Sediment ponds <br />will be filled in and topsanded. All pit roads will be filled to AOC, <br />scarified, topsanded, fertilized, and seeded. Power lines will be removed. <br />Water wells will be sealed and grouted. <br />-8- <br />