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i <br />Project: Church-McKay SWMP <br /> Hall-Irwin, Inc. <br />Owner: <br />To: Chris Lang/Jim McFarland <br />From: Civil Resources, LLC <br /> Andy Rodriguez, P.E. <br />Date: February 4, 2009 <br />RE: Hall-Irwin Corporation, File No. M-1987-113 Church-McKay Storm Water <br />Management Plan (SWMP). <br />Civil Resources, LLC has completed our preliminary engineering analyses of the drainage and <br />erosion control issues at the Church-McKay Mine. <br />Introduction <br />Civil Resources, LLC has completed a Stormwater Management Plan (SWMP) for Hall Irwin's Church <br />McKay hard rock mine site. The Church McKay site is located approximately 2,000 feet east of the <br />intersection of Highway 93 and Rocky Flats Plant Road. The SWMP was prepared in general <br />accordance with the Colorado Department of Public Health and Environment (CDPHE) Water Quality <br />Control Division's Appendix A - Stormwater Discharges Associated with Sand & Gravel Production <br />Operations. Please see Figure 1 for a site location map. <br />Site Description <br />The site is approximately 95.07 acres in size and was an abandoned hard rock mine. Hall-Irwin <br />purchased the site approximately 1 year ago. It is located in Section 9, Township 2 South, Range 70 <br />West of the 6`h P.M in Jefferson County, Colorado. Coal Creek is located approximately one and one- <br />quarter mile west of the site. The property is bordered on the north, east, and west by Rock Flats <br />and the Rocky Flats Plant Road to the south. The Upper Church Ditch and McKay Ditch bisect the <br />property as they flow easterly across the site. <br />Hall-Irwin Corporation proposes to mine the Site for hard rock. The existing site topography is <br />generally characterized as sloping northeast towards Coal Creek. A map of the soils and hydrological <br />groups identified at the subject site can be found at the end of this SWMP. <br />According to the Soil Conservation Service Web Soil Survey results, the property soils are Flatirons <br />very cobbly sandy loam, Nederland very cobbly sandy loam, and Pits, gravel, please see the soils <br />map attached at the end of this report for details. <br />Runoff from the site will continue to flow north and northeast to Rock Creek a natural drainageway <br />tributary to Coal Creek located at the northern end of the site. <br />Site Map <br />A site map showing the mining site boundaries; access and haul roads; stormwater outfalls and an <br />outline of the drainage area of each stormwater outfall; an estimate of the direction of flow; materials <br />handling areas; existing structural control measures; areas used for storage or disposal of <br />overburden, materials; soils or waste; areas used for mineral milling and processing; springs; <br />streams; wetlands and other surface waters; location of mine drainage or any other process water; the <br />boundary of tributary area that is subject to effluent limitations and the date the map was prepared is