2011-09-19_PERMIT FILE - M2011049 (7)

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Nature of Deposit to be Mined Un -mined portions of the Treiber Lakes site are composed of Pleistocene and recent age valley - fill materials that make up the alluvial floodplain of the Cache la Poudre River. The alluvial material may have previously occurred naturally at the surface, but past mining and reclamation activities appear to have placed soil cover over most of the site. The alluvial deposit extends to a variable depth of 15 to 25 feet below the ground surface. Upper layers of the Pierre Shale Formation underlie the alluvial material in and surrounding the proposed permit area. The relatively impermeable characteristics of the shale create a bottom seal for reservoir construction and water storage development. Sand and gravel for use as construction materials were the primary products produced from the proposed Treiber Lakes site. It appears that mining setbacks from the proposed permit boundary ranged from 25 to 50 feet. At this point, backfill and grading has created approximate 3H:1 V slopes to the lake water surface and it is believed that these slopes continue to the lake bottom. Distances from the proposed permit boundary to the water surface of the lakes ranges from 50 to 200 feet. The slurry wall for final reclamation will be constructed within this setback area. Although it is believed that all marketable materials have been removed from the site, reclamation activities may involve additional excavation and backfilling of materials on the site. If excess marketable aggregate material is found, the material may be removed from the site. The intended use for the sand and gravel would be for construction aggregates. Permitted mining operations are immediately north, east, and south of the proposed site and City of Fort Collins open space is adjacent to the western permit boundary. The dominant non - mining land use surrounding the property is agriculture and rural to semi -rural residences. Items owned by the applicant located within the proposed permit boundary such as roads, fences, water wells and associated pumps, and other structures may be removed or relocated during the reclamation process. A power transmission line and pole owned by Platte River Power Authority crosses through the middle of the site. Additionally, utility lines owned by Mountain States Telephone and Telegraph (a.k.a. Mountain Bell, US West, Qwest Corporation) are located along the proposed southern permit boundary. These transmission lines are associated with recorded easements and neither the structures nor easements will be negatively affected by site reclamation activities. All other structures on the site are owned by the applicant. Man-made structures within 200 -feet of the proposed permit boundary include fences, the Poudre Trail, power transmission lines and poles, utility lines, and mining conveyors and associated equipment. No mining highwalls will be created, no mining will take place within 200 feet of man-made structures, and all excavations and slopes on the site will remain stable. Since all reclamation activities will be performed within the permit boundary, no impacts to man-made structures outside the permit boundary are anticipated. (see Exhibit S, Permanent Man-Made Structures within 200 Feet of the Affected Land). Treiber Lakes DRMS 112 Permit Application Page 5