2013-09-18_PERMIT FILE - M2013064 (9)

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Exhibit I & J — Soils & Vegetation Information remaining above the anticipated static water level of the completed reservoir basins. Windrowed salvage soil stockpiles will be graded such that the side slopes are 3H:1V or flatter. This will aid seeding and vegetation efforts while reducing the profile exposure of the stockpile to wind and water erosion, keeping the material stable until used for reclamation. Direct precipitation from short duration, high intensity rainstorm events, and wind, are the major threats to soil stability at this location. Although the location is nearly a table, and although the extraction will result in basins that cause water from direct precipitation to drain internally, additional measures will be taken to assure site stability and protection of off -site areas. The operator's stormwater management plan provides additional detailed information about maintaining on -site stability consistent with its pending Colorado Department of Health stormwater permit, and is available upon request by the Colorado Office of Mined Land Reclamation. The measures taken to stabilize the soil stockpiles, as described above, should be adequate for controlling erosion from wind and direct precipitation. Due to the flat topography of the parcel, the interception of upland overland flows by local irrigation ditches and surrounding roads, there is little upland watershed that would impact these locations. The greater threat of erosion will be to resoiled slopes pending establishment of vegetation during reclamation. While some sheet and rill erosion can be anticipated on unprotected areas following seed bed preparation and seeding, the conservation measures provided below should help to limit erosion potential that would threaten the revegetation efforts. Prior to resoiling, the foundation material that will underlie the soil will be sculpted to establish initial soil stabilization features, and left rough to aid in resoil adherence. Soil will be placed over a 12 -18± inch minimum friable, or otherwise unconsolidated, subsoil. A 12 -18± inch swale with slopes of 3H:1V or flatter will be placed above finished slopes where necessary to direct any upland surface flows around the finished slopes to an established stable drainage corridor. Resoiled areas will be allowed a minimum of three months to settle prior to seeding. Seeding will follow in the fall or spring as detailed under Exhibit E — Reclamation Plan. Resoiling will occur when soil moisture is adequate to prevent blowing, yet dry enough to prevent compaction. Part of the soil rebuilding process on the reconstituted soils will be in establishing structure to the soils to facilitate plant -soil -water relationships. Overly compacted soils will tend to limit soil structure development and create a poor seedbed for later establishment. Once applied to the surface, the new soils will be exposed to the raw forces of erosion until adequate vegetative cover and root mass develops. Erosion requires both Varra Companies, Inc. Varra- Coulson Resource Project 4 OMLR 112 Permit Application 8 August 2013