2006-08-02_PERMIT FILE - C1980007 (10)

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' geotextile separation fabric will be placed between the natural channel area and the roadway fill. This will provide the best opportunity to restore the existing channel when the road area is reclaimed. Being naturally hardened, it is expected that the soils in this area are stable and will not jeopardize the overall stability of the roadway. The drainage structures were designed for the 100 year 24 hour storm based on USFS requirements on their portion of the project. This was also utilized on the MCC property portion of the project. The hydrology/hydraulics design is summarized in Section 6.0 of this report. SECTION 3.0 TOPSOIL STORAGE It is estimated that approximately 6,895 cubic yards of topsoil will be removed to construct this project on both MCC and USFS property. Topsoil will be temporarily stored between stations 124+00 and 130+00 during construction. Approximately 1,790 cubic yards will be utilized after the road is constructed to revegetate the side slopes of the roadway. Approximately 5,105 cubic yards of topsoil will be stockpiled after construction is completed on MCC property at the proposed primary borrow site. The pile will be placed against the existing topsoil pile with slopes no steeper than 2 horizontal to 1 vertical. SECTION 4.0 SUBSOIL STORAGE • This project will not create any excess subsoil that is not utilized in the roadway construction. No subsoil stockpiles aze presented in this report. SECTION 5.0 GEOTECHNICAL STUDIES 5.1 Field Investigations A drilling field investigation was conducted on the proposed road in March 2003. It was originally proposed that 19 drill holes be placed along the proposed route. However, only 13 of the 19 proposed holes were completed as snow and ice conditions prevented the completion of six of the planned holes. The locations of the planned and completed borings are shown on Figures 1 through 6. The 13 soil borings were drilled with a drill rig operated by DA Smi[h Drilling Company under the direction of Pat Peterson of Environmental Strategies Corporation (ESC). The soil borings were advanced using an 8 inch hollow stem auger. Standard Penetration Tests were taken at 5-foot intervals using the appropriate ASTM procedures. All soil samples retrieved during the drilling operation were placed and sealed in plastic bags and shipped to Geotechnical Engineering Incorporated (GEI) for laboratory testing. Several Shelby tubes were pushed into the underlying clay soils to obtain suitable samples for shear and triaxial testing. The drilling • logs for the 13 drill holes can be found in Appendix C of this report.