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given time. Reclamation will occur on mined out areas concurrently with mining. Overburden <br /> will be used to supplement the topsoil to be used as growth medium. Growth medium will be <br /> placed back during reclamation at a depth of 12 inches. <br /> Backfilling will not be needed as mining will take place to the final slopes of 3H:IV. The <br /> proposed operation is exploiting a valley floor alluvium deposit with the following <br /> characteristics: <br /> • Deposit depth minimum of 50 feet <br /> • negligible recoverable overburden <br /> • zero to twelve inches of topsoil above the gravel resource <br /> 1.2 Site Geology <br /> The gravel deposit consists of unconsolidated Quaternary alluvium and glacial deposits underlain <br /> by Precambrian metamorphic and igneous rocks and Paleozoic sedimentary rocks. The following <br /> are geologic descriptions of the units to be exploited, see attached Climax Quadrangle Geologic <br /> Map, Lake and Park Counties, Colorado 1 and Geologic Map of the Leadville North 7.5' <br /> Quadrangle, Eagle and Lake Counties, Colorado for spatial relationships of units Note that unit <br /> designations are from the Climax Quadrangle Map, and correlate with Units Qa and Qac of <br /> Leadville North 7.5' Quadrangle Map. <br /> Unit Qal - Stream-channel and flood-plain alluvium (late Holocene). Deposits are mostly clast- <br /> supported, pebble, cobble, and locally boulder gravel in a sandy silt matrix. Deposits are locally <br /> interbedded with and commonly overlain by sandy silt and silty sand. Clasts are subangular to <br /> well-rounded and their varied lithology reflects the diverse types of bedrock within their <br /> provenance. This unit includes modern stream channel deposits of all perennial streams, adjacent <br /> flood-plain deposits, and low-terrace alluvium that lie a maximum of 10 ft above modern stream <br /> level. The largest mapped areas are in the channels and floodplains of perennial streams (East <br /> 1 McCalpin,J. P.,Temple,H., Sicard, K., Mendel,D.,&Ahmad, B.(2012). Climax Quadrangle Geologic map, <br /> Lake and Park Counties,Colorado. Golden: Colorado Geological Survey,scale, 1(24),000. <br /> '-Ruleman,C. A., Brandt,T.R.,Caffee,M. W.,&Goehring,B. M.(2018). Geologic map of the Leadville North <br /> 7.5'quadrangle,Eagle and Lake Counties,Colorado(No.3400). US Geological Survey. <br /> Birdseye Pit Greg t.rNtcki and Asvwiatrs,PIJA <br /> June 2019 D-3 <br />