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COMPANY: <br />MINE: <br />PERMIT NO: <br />DATE OF INSPECTION <br />WEATHER: <br />COMPANY OFFICIALS <br />STATE OFFICIAL: <br />OSMRE OFFICIALS: <br />DENVER FIELD BRANCH <br />INSPECTION NARRATIVE <br />Coors Energy Company <br />Keenesburg Mine <br />C- 1981 -028 <br />February 5, 2015 <br />Cold and partly cloudy, mid 30's <br />Danny Kipp and Ben Moline <br />Jared Ebert <br />Flynn Dickinson and Thomas Medlin <br />A partial inspection of the Keenesburg Mine was conducted to determine acceptability for Phase I bond release. <br />This inspection was focused on the Phase I release of the bond associated with 27.1 acres of reclaimed area <br />where backfilling and grading had been completed in accordance with the terms of the approved permit. Three <br />parcels were listed as candidates for Phase I bond release in the company's application: Area 30, Area 31, and <br />Area 32. The requested amount for bond release in this case was $321,794. <br />Colorado's rules regarding Phase I bond release requirements are outlined at Rule 3.03.1 of the Regulations for <br />the Colorado Mined Land Reclamation Board and allow for up to sixty percent of the applicable bond amount <br />to be released upon meeting all Phase I requirements. For the completion of Phase I, the operator must <br />complete the backfilling/regrading (which may include the replacement of topsoil) and drainage control of a <br />bonded area in accordance with the approved reclamation plan and meet all applicable performance standards, <br />including but not limited to: <br />• Backfilling and grading disturbed areas to achieve the approximate original contour with the elimination <br />of all highwalls, spoil piles, and depressions <br />• Achieving a post- mining slope that does not exceed either the angle of repose or such lesser slope as is <br />necessary to achieve a minimum long -term static safety factor of 1.3 and to prevent slides <br />• Minimizing erosion and water pollution both on and off the site <br />Although the mine hasn't produced coal since the late 1980's, it has been kept open to accept coal ash disposal <br />within the pits from the Coors Beer factory in Golden. Colorado DRMS granted an AOC variance in the permit <br />to accommodate this disposal. The reclamation plan requires a clay liner below the ash disposal areas and all <br />sections of the mine are covered with a minimum of 6 feet of spoil and 2 feet of A and B horizon topsoil, or <br />"topsand" as referred to by mine personnel. <br />Of the areas proposed for release, Area 30 was graded, topsoiled, and seeded in the fall of 2006 and Area 31 <br />was in the fall 2009. Area 32 had only been backfilled and graded, with most of the work having occurred in <br />November of 2013. Colorado DRMS personnel collected GSP coordinates during the inspection to verify that <br />AOC requirements had been met and that the maps submitted in the bond release application are accurately <br />portraying real elevations. An additional measure DRMS has implemented to verify spoil and topsoil cover is <br />that they track placement over time through the use of gages (poles) placed on the reclaimed area by the <br />company. Each gage tracks the placement of spoil as it is backfilled and the spoil is documented at a higher <br />level on the gage over time. This information is documented by DRMS as work continues over time in given <br />parcels. Although this methodology is only as accurate as the placement pattern for the gages allows, much as <br />other methods, it makes sense at this site given the larger depth of spoil cover. <br />There was little to review regarding the establishment of drainage control. The soils in the area are sufficiently <br />sandy that little or no runoff occurs even in response to significant rainfall event. Consequently, we inspected a <br />