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<br />1. INTRODUCTION <br />Cooley Gravel Company (Cooley) proposes to develop a surface sand and gravel mining operation <br />with appurtenant asphalt and concrete batch plane on approximately 213 acres of land in Weld <br />County. The property is located neaz Rion, just north of County Road 20.5, east of Boulder Creek, <br />and approximately six miles east-southeast of Longmont, Colorado. This document waz prepared by <br />Haley & Aldrich, Inc. on behalf of Cooley az application to the State of Colorado Division of <br />Minerals and Geology (DMG) for a Regular (!12) Mining and Reclamation Permit, and to the Weld <br />County Planning Commission and Board of County Commissioners for a Use Hy Special Review <br />Mining Permit. <br />The site is currently used az rangeland for cattle and is partially irrigated by water from the Smith and <br />Emmons Ditch. The site is entirely within the 100-year floodplain. A wildlife assessment revealed <br />no threatened or endangered species, nor any critical wildlife habitat. Present vegetation consists of <br />pasture grasses with cottonwood trees along Boulder Creek. A wetlands delineation identified <br />jurisdictional wetlands only along a narrow cortidor along Boulder Creek and these will be protected <br />by a riparian buffer zone that will not be mined. <br />Cooley proposes to mine the property in four phazes during approximately 15 to 20 years. The <br />proposed mining will consist of dry mining with dewatering via perimeter trenches or wet mining <br />with a dragline. The site contains approximately t5 to 20 feet of alluvium and topsoil soils overlying <br />clay shale bedrock which acts az an aquitard between the alluvial aquifer and deeper bedrock aquifers. <br />A partial, optional, slurry wall has been considered to limit ground water inflows to the operation and <br />to protect adjacent water resources, if necessary. No negative impacts to Boulder Creek are <br />anticipated. <br />Proposed reclamation will consist of either an open lake or a sealed water storage reservoir, both with <br />irregular, revegetated shorelines to blend with the surrounding land use. The open lake option will <br />entail ground water depletions via evaporation which will be augmented. The sealed water storage <br />reservoir option will require construction of a slurry wall surrounding the site to separate ground <br />water from stored water. Reclamation will be concurrent with mining and will include revegetation <br />r1 <br />LJ <br />/"l~/1 <br />