1986-11-28_GENERAL DOCUMENTS - C1981017

Home Browse Search

Mr. George Wear - 2 - October 29, 1986 Item #1 Mine B2 Mine #3 Mine #4 Mine #5 Mine Push Distance 100' 75' 150' 200' 1DO/200 Unadjusted Production 920 Icy/hr 1180 Icy/hr 680 lcy/hr 520 920/520 Correction Factors Operator .75 .75 .75 75 .75 Material .70 .70 .70 70 .70 Job efficiency .83 .83 .83 .83 .83 Grade .60 .68 .68 .82 .53/1.23 Altitude .92 .92 .92 .92 92 Adjusted Production 221 Icy/hr 322 lcy/hr 185 lcy/hr 171 Icy/hr 195/256 Volume 21,065 Icy 333 Icy 53,333 12,500 36,667 Job Time 95.3 hrs 10.4 hrs 288.3 hrs 73.1 hrs 165.6 hrs Cost per hr 118.00 118.00 118.00 118.00 118.00 Total Cost 1TI-Mrdif 34,019,7b _Krz6:8o I9,,SZFW In addition, it appears that Mid-Continent has not included the two storage pads (No. 3 & 4) associated with mines 1 & 2 in the backfilling estimates. Mid-Continent should include these pads, or discuss their omission with respect to Jim Herron's original calculations. Mid-Continent should also verify that cut and fill volumes balance at each pad. The cross-sections presented indicate that mines 3 & 5 may have a material shortage. The cross-sections and topography maps should then be prepared so that they can be inserted into the bonding section. Locations of all cross-sections should be clearly marked on the plan maps. 2) The Division has reviewed the backfilling and grading plan for the haul roads and found the general design to be acceptable. However, estimates for normal sloughing seem to be high. Mid-Continent estimates 30-40% of the required material will slough in two years. However, the reclamation plan calls for completion of all reclamation in the second year. Using the more conservative figure of 30%, the Division will allow for 15% sloughing during the first year. The remainder of the material would have to be moved (by equipment) in the second year. This would require that 272,759 c.y, of material be imported, with an additional 99,329 c.y. being obtained from the cut slopes. In addition, Mid-Continent must identify the specific borrow areas from which material will be imported. If these areas are previously undisturbed, then a reclamation plan must be developed for them. Each area should be located on a map, with the approximate volumes listed next to it. Lastly, the Division feels that Mid-Continent should re-evaluate the use of scrapers for this work, due to the manuverability contraints of the haul road reclamation. Mid Continent must either demonstrate that there is sufficient room for a scraper to operate or recalculate the backfilling costs using a truck-loader team. In either case, a volume of 272,759 c.y. should be -used.