Laserfiche WebLink
January 10,2014 <br /> Page 7 of 8 <br /> Topsoil has been salvaged from prior mining operations and used to construct the screening berms <br /> that are in place around the perimeter of portions of the Site to be used as part of final reclamation. <br /> The volume of topsoil that is stored in these berms is just over 50,000 cy. The volume associated <br /> with each stockpile is indicated on Sheet Cl,Existing Conditions. In addition,the southwestern <br /> portion of the property north of 2215'Ave. and the southern expansion parcel has yet to be stripped <br /> (27 acres and 14 acres respectively). The topsoil ranges in depth from 6-12 inches. Using an <br /> average of 8 inches over the 41 acres remaining to be stripped yields an additional 44,000 cy of <br /> topsoil for a total of approximately 95,000 cy of topsoil available for on-site reclamation. This <br /> exceeds the topsoil requirements for reclamation of the entire site based on ordinance requirements <br /> of three inches over the 114 acre disturbed area or 46,080 cy(The 114 acre area requiring topsoil <br /> excludes the northern portion of the Site which was sold to Elk River Landfill for future landfill <br /> expansion,but includes 221'Ave. and the new alignment). <br /> Topsoil Available: Topsoil Required <br /> Perimeter Berms: 51,572 cy <br /> Future Mining Areas (8") 44,098 cy <br /> Total Topsoil Available On-Site 95,670 cy 46,080 cy <br /> 3:1 Slope Revision to 4:1 Slope: <br /> Final Slopes have been revised along the southern boundary to 4:1 and are illustrated on the revised <br /> Sheet C3,Reclamation Plan. It is anticipated that this southern property line will eventually be <br /> mined through to match grades to the south. Slopes along the McCrossan west boundary remain at <br /> 3:1 along the power line. It is also anticipated that in the future the southern and western property <br /> lines which represent common mining borders will be excavated and these slopes will be <br /> eliminated. The power lines along the McCrossan west boundary would need to be relocated or <br /> lowered in order to mine the common border but it is anticipated that this will occur in conjunction <br /> with the realignment of 2215`.Ave. <br /> Earth Work Balance: <br /> The volume of material required to bring the site from excavation grades to proposed <br /> reclamation grades is 1,543,996 cy. Assuming a 20%compaction factor, 1,852,795 cy of <br /> material will be needed to bring the site from the excavation grades to the proposed <br /> reclamation grades. <br /> There is sufficient material on-site to accomplish reclamation grading. An estimated 2,348,400 <br /> cy of material is available on from on-site sources; from materials encountered in the deposit <br /> during mining such as clays and other materials too fine to process into marketable aggregate <br /> products (2,150,000 cy) and overburden from the unstripped areas of the Site (198,400 cy). <br /> Based on the past mining activity at the Site, an estimated 20% of excavated materials will be <br /> suitable as compactable backfill and an average of three feet of stripping over the unmined 41 <br /> acres is also available. <br /> Future Roadway Grades: <br /> The future roadway grades have been revised along with the other end use contours to reflect <br /> roadway grades of 0.5-8% and to maintain a minimum of five feet above the updated water <br /> table contours. Revised grades are illustrated on Sheet C3, Reclamation Plan. <br /> Specifics of Re-vegetation: <br />