PERMFILE109479 - Laserfiche WebLink

Home Browse Search

EXHIBIT G Water Information The Wattenberg Lakes site is located in Weld County south of the Town of Wattenberg. The site lies between the Brighton Ditch and the west bank of the South Platte River. The Pre- Mining/Mining plan Map (Exhibit C) illustrates water resources on the site. The South Platte River runs along the eastern border and through the northeastern corner of the site. The Brighton Ditch runs along the westem boundary of the site. No impacts to the Brighton Ditch will result from mining. The Huett Seepage Ditch runs through the eastem half of the site and the Brighton Ditch runs along the westem border of the site. The Huett Seepage Ditch will be relocated prior to mining at the site. Mining of the Wattenberg Lakes site will last for approximately I 1 yeazs. As the material is removed, concomitant reclamation will occur with the construction of three slurry walls enclosing three of six mining areas on the site. The three mining azeas that will not be enclosed within slurry walls will be backfilled or will be used to create mitigation wetlands or riparian area on the site. Once reclamation is complete, three reservoirs will be created and will have a combined surface area of approximately 187 acres. Generally, the mined material will not be processed on-site. Once material is recovered, it will be conveyed across the South Platte River to an existing permitted sand and gravel mining operation for processing. If necessary, some temporary processing may occur on-site. The site will be mined in six mining azeas of varying sizes. Mining azeas will be either dry or wet mined. If dry mined, groundwater will be exposed in dewatering trenches and collection basins and prior to mining, dewatering trenches will be excavated in the mining areas. Groundwater and storm water will flow along trenches by gravity to the collection basins. Prior to discharge into the South Platte River, the collected groundwater and/or storm water will be evaluated for pollution content. The mining operation will impact groundwater systems hydraulically connected to the South Platte River. The depth to groundwater ranges from approximately zero to 10 feet. The operation will extract sand and gravel deposits from the South Platte River alluvial aquifer. This unconfined alluvial aquifer rests atop the outcropping of the Arapahoe aquifer. Water below the property within this portion of the Arapahoe is considered not non-tributary. The Lazamie-Fox Hills aquifer lies below the Arapahoe aquifer. Water below the property within this portion of the Laramie-Fox Hills is non-tributary. As delineated on FIRM panels 995 and 983C from September 28, 1982, the entire site except for a portion of the northwest corner and a small peninsula midway along the western border is located within the South Platte River 100-year flood plain. All work performed in the floodplain will conform to the Weld County Flood Hazard Regulations. Wattenberg Znkes OMG ]/1 Permit Page ]4