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provided for each quarry indicate that a majority of the reclaimed slopes will be 4:l or greater and that a. long, narrow pit will be left that is approximately 150 feet wide and lessihan 20 feet deep. Fo:r purposes of determining a reclamation cost for each quarry, the Division will adhere to the criteria provided in the 1977 and 1985 applications as closely as possible since these are the presently approved reclamation plan contours. OVERBIfRDEN VOLUMES The volumes of overburden to be moved as provided in your January 16, 1998 report appear to be only those required to achieve a maximum slope of 2:1 throughout all affected land to be reclaimed. For purposes of determining a reclamation cost for each quarry, the Division must calculate ~rverburden volumes to be moved according to the criteria listed in the 1977 and 1985 applications as closely as possible since these aze the presently approved reclamation plan contours for each site. Please be advised that you have the right to revise your reclamation plan at any time. BLASTII`fG The costs provided in the January 16, 1998 report for blasting of the east highwalls were based upon a typical slope of 0.8:1 at 50 vertical feet. Based upon a review of the information provided in the permit, the recent map of existing topography, and field observations and photographs, it appeazs that a typical slope of neaz vertical is more accurate. The only locations where a slope of 0.8:1 are noted aze where stockpiles of product or other fine grained material, located on an adjacent mine bench, have sloughed or have been pushed over the edge. The Division requests that Colocido Lien revise the typical drilling and blasting cross section and associated cost to show the extent of drilling and blasting needed to produce a 2;1 slope from an almost vertical highwall. Please address this concern. Consideration will need to be given to the need for blasting of lazge rocks left in overburden stockpiles where the size and weight of these rocks is either greater than the capacity of the equipment used to move it or significantly reduces the efficiency of the equipment used to move it. Please +tddress this concern. PUSH/HAUL DISTANCE Colorado Lien has provided an estimate of push distances for overburden material to be moved in each qutury in the January 16, 1998 report. It should be noted that the representative cross sections provided, based upon reclaimed slopes of 2:1, consistently show a major cut and resulting material excess in the overburden slopes of the Rex Quarry and a major fill and resulting material deficit in the pit azeas of the Owl Canyon Quarry. Therefore, it will be necessary to include in the reclamation cost determination for each quarry acut-fill analysis that considers volumes of overburden material to be moved both in a west-east direction as well as a north-south direction. The Division must include, in the reclamation cost determination for each quarry, costs for moving overburden in either north-south or west-east direction where appropriate.