2003-12-11_REVISION - M1998014 (2)

Home Browse Search

The permit area is not prone to flooding from adjoining properties or the two nearby Spring Creek and Alkali Creek, both of which are intermittent drainage channels. The predominate drainage course found in the vicinity of the site is the Eagle River, which is north of the permit boundary and flows appro~mately 60 feet below the site. A review of the Flood Rate Insurance Map for the area indicates, that none of the disturbed areas on the site are prone to flooding by the river. Mining is conducted in a manner that will not increase the discharged amount of surface stormwater runoff above historic flows. Any stone water runoff entering the site will be captured within the pit area and allowed to evaporate or percolate into the ground. In order to maintain the quality of any surface storm water, which crosses any e~osed ground areas, a Storm Water Management Plan (SWMP), has been prepared. The Colorado Department of Public Health and Environment has issued a permit. A key element of the plan calls for grading the area in a manner that will not allow the discharge of any silt laden storm waterfrom the property in the event of a storm. Thus, eliminating any stormwater discharges from the disturbed areas of the site. This is accomplished by utilizing a 3 foot high dike adjacent to and above the river. The dike will direct flows to a shallow Swale and ultimately to the e>asting pond area on the property. A drainage analysis is presented on the following pages. The analysis indicates that the various stormwater conveyance elements are property s¢ed in the event of a major storm event. Water is used on site when necessary to control dust in the mining area, during crushing operations, and on haul roads. Water for dust control is obtained from the aforementioned pond. Water is also consumed for the operation of the wash plant. The water supply for the consumptive uses is from ebsting water rights in the Stremme and Gates Irrigation Ditch located on the property. Water is pumped from an e~dsting well adjacentto the Eagle River and stored in the ebsting pond. Estimated ma>amum annual water requirements follow: ~ USE ~ ,. AC. FT. PER YEAR Sand and Gravel Washin 3.66 Dust Control 6.54 Concrete Production 1.84 Truck Washin 0.45 Pond Eva oration 3.98 Domestic 0.06 TOAL 16.55 RECEIVE® DEC 2 2 2003 Division of Minerals and GealoBV Rev. 08!10/03