Laserfiche WebLink
Parkdale Quarry Amendment #1-Bond Phasing Calculations <br />Apri12008 <br />Sand and Gravel Reclamation Phase I (Year 41 <br />This phase of the Sand and Gravel operation is characterized by active mining in the approximately <br />western 1/3 of the Sand and Gravel mining limit. This phase uses the same assumptions in terms of unit <br />costs as Phase II. This phase is assumed to take place at year 4 of the mining operation. The key <br />differences are as follows: <br />• Some reclamation has generally been performed in the northwest area of the western 1/3 of <br />the pit. As a result, a 30-foot high liner of approximately 5600 linear feet is used to calculate <br />Aspect A. <br />• Approximately 7100 linear feet of the 40-foot mining highwall will need to be reclaimed. <br />• Approximately 8 acres from topsoil and overburden stockpiles will need to be reclaimed. <br />Phase II descriptions for product stockpiles, sedimentation ponds, access road and office, conveyer belt <br />system and processing plant removal, dewatering trench, stormwater reclamation, inlet and outlet <br />facilities for reservoir, and berms are the same as the reclamation Phase I calculation. <br />Sand and Gravel Reclamation Phase III (Year 121 <br />This phase of the Sand and Gravel operation is characterized by active reclamation only in the <br />approximately eastern 1/3 of the Sand and Gravel mining limit. It is assumed that reclamation is <br />complete for the areas mined in Phase I and along the southern portion of the area mined in Phase II. It <br />is also assumed that reclamation is in process for the northern portion of the area mined in Phase II. <br />This phase uses the same assumptions in terms of unit costs as Phase II. During this phase, there is no <br />processing facility, no sedimentation ponds, and no dewatering trench since mining is anticipated to be <br />complete. This phase is assumed to take place at year 12 of the mining operation. As a result, there is <br />less disturbance than in Phase II. The key differences are as follows: <br />• Reclamation of the exposed mining face includes the remaining 8,640 linear feet of the 15-foot <br />wide clay liner along the north, east, and south perimeter of the western 1/3 of the mining limit. <br />This phase also includes lining approximately 16 acres of the reservoir bottom in this area. <br />• Approximately 1 acre from topsoil and overburden stockpiles will need to be reclaimed. <br />Phase III descriptions for product stockpiles, access road and office, stormwater reclamation, inlet and <br />outlet facilities for reservoir, and berms are the same as the reclamation Phase I calculation. <br />3~Page <br />