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Fork Arkansas River and Evans Gulch) where channel facies are small pebble gravel and <br /> floodplain facies are medium to coarse sand. Smaller areas lie in the channels of intermittent <br /> streams. Deposits may be interbedded with colluvium or debris-fan deposits where the distal <br /> ends of fans extend into modern river channels and flood plains. Maximum thickness is normally <br /> about 33 ft but may overlie thicker (100 ft?) Pinedale-age lake beds and older alluvium in the <br /> East Fork Arkansas River. Areas mapped as alluvium may be prone to flooding and sediment <br /> deposition. The unit is typically a quality source of sand and gravel. <br /> Unit Qat- Low stream terrace alluvium (Holocene). Deposits are mostly clast-supported, <br /> pebble, cobble, and locally boulder gravel in a sandy silt matrix. This unit includes alluvium of <br /> low terraces above the modern floodplain, most of which is inferred to be early to middle <br /> Holocene in age, but some may have been deposited as part of the latest Pinedale glacial <br /> outwash. The unit is mapped on the floor of the East Fork Arkansas River downstream from <br /> English Gulch. Deposits are locally interbedded with and commonly overlain by sandy silt and <br /> silty sand. Clasts are subangular to well rounded and their varied lithology reflects the diverse <br /> types of bedrock within their provenance. Maximum thickness probably less than 20 ft. <br /> Unit Qfp - Alluvial-fan deposits, older (late to middle Pleistocene). Moderately sorted sand-to <br /> boulder-size gravel in dissected fan-shaped deposits from tributary streams. Deposits typically <br /> composed of both matrix supported beds (debris flow facies) and clast-supported beds <br /> (streamflow facies), often interbedded. Clasts are mostly angular to subangular. Deposits are <br /> inferred to be contemporaneous with the Pinedale glaciation from their relationship with end <br /> moraines. The maximum thickness is at least 16 ft. <br /> The Leadville North 7.5' Quadrangle Map includes the location of a drill hole approximately 2.5 <br /> miles southwest from the Birdseye Pit and within the unconsolidated alluvium that will be mined <br /> by the Birdseye Pit. This drill hole indicates an alluvium depth of 152 feet and it is anticipated <br /> that a similar depth to bedrock will be found at the proposed location of the Birdseye Pit and that <br /> a proposed pit depth of 50 feet should present no issues with alluvium availability. <br /> 1.3 Commodities to be Mined <br /> The primary commodities to be mined/extracted are sand and gravel to be used for construction. <br /> A proposed asphalt plant and a concrete batch plant will use the processed material from the pit <br /> Birdseye Pit GIef"Ixwnks and %S*kclalew PI I f <br /> June 2019 D-4 <br />