Laserfiche WebLink
contour. Caterpillar D10T dozers were selected as the most cost efficient equipment, given <br /> the average distances calculated. These push distances and volume calculations for the <br /> roadways are based upon typical cross sectional areas. These areas were applied to <br /> projected road lengths during the worst case year of 2022 as shown on Map M9. From <br /> these values, regrade times, as shown in Table A-6, were calculated. Costs were also <br /> included for ripping haulroads using a material seismic velocity of 5000 fps. <br /> Trapper is careful not to introduce materials on roads that will require removal at a later <br /> date. That is specifically why the use of ash on haul roads has not been pursued. Roads <br /> are constructed of earthen fill and sub-base material with gravel on top. Scoria may also be <br /> used if available. These inert materials are easily graded during reclamation, covered with <br /> topsoil, and do not adversely affect the growth of vegetation. Post mining land use <br /> requirements are not compromised. <br /> Drainages affected by road fills include Far East Buzzard, Coyote, No-Name, Johnson, West <br /> Pyeatt, Middle Pyeatt, East Pyeatt, Grouse, Sage, Oak, Flume and Deal. <br /> 1.4.1.3 Impoundment Regrading <br /> Calculation of regrade times for existing and future impoundments is shown in Table A-7. <br /> Impoundment volume calculations are shown in Table A-7 (1-2) of Appendix A. Many of the <br /> impoundments were approved as permanent structures by the Division. As a result, they <br /> will be left in place. Impoundments requiring reclamation include Far East Buzzard; Coyote; <br /> Middle Pyeatt 1, 2, and 3; Sage, West Horse, Deal 1 and 2; Jeffway 1 and 2; and Deacon 1 <br /> and 2. <br /> The earthen impoundments would be graded with dozers, filling back the areas from which <br /> the material had been previously removed. Caterpillar D10T dozers equipped with a semi-U <br /> blade were used to develop cost data and productivity. This regrading would establish the <br /> approximate original contours in the affected areas. <br /> 1.4.2 Topsoiling <br /> After regrading, topsoil from permanent stockpiles would be placed on all disturbed areas, <br /> except for such minor disturbances as light duty access roads, where topsoil was never <br /> removed. Topsoil replacement costs are summarized in Table A-9. Productivity and cost <br /> values are for Caterpillar 637G scrapers, and a Caterpillar 5130 excavator with Caterpillar <br /> 777C trucks. These equipment types, and particular models, were selected as a cost <br /> efficient means of loading, transporting, and uniformly spreading the topsoil. TALPAC <br /> software was used to determine scraper and truck/trackhoe production per hour. The areas <br /> requiring topsoil replacement would include all active, inactive, and abandoned pits, and <br /> their associated roadways, impoundments, and the industrial complex area. <br /> Map M10B illustrates topsoil removal and replacement activities for each year of the permit <br /> term, including the worst case year of 2022. This map is the basis for pit disturbance areas. <br /> The industrial complex area, and other topsoil replacement areas were calculated from mine <br /> workings maps. <br /> A topsoil replacement area for roadways was calculated for roadways lengths as shown on <br /> Map M9 and roadway disturbance widths. <br /> For each of the topsoil replacement areas, a typical spread point location was established <br /> from which average haul distances and grades were determined based upon their locations <br /> 1-35 revisions P�4-off <br /> Approved <br />