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7. Groundwater Groundwater is located approximately four to five feet below the surface at the Delta Paving site. This is evident from the permittee's experience of mining at the site and the water levels experienced in the reclaimed lakes onsite. Five gravel well permits are approved for the operation and are located in various locations on site that correspond with historical mining plans. An additional two wells are located just outside the permit area; one to the east of the site, and one to the southwest. These well locations are shown in Map C-1. Table G-4 identifies each well. Table G-4 Wells Within 600' of Permit Area Total Distance from Depth nearest mining Applicant/Well ID Permit ID (feet) Purpose area (ft) Delta Paving Pit Well No.1 053787-F 25 Industrial Uses 245 Delta Paving Pit Well No.2 053787-F 25 Industrial Uses 370 Delta Paving Pit Well No.3 053787-F 25 Industrial Uses 350 Delta Paving Pit Well No.4 053787-F 25 Industrial Uses 0 Delta Paving Pit Well No.5 053787-F 25 Industrial Uses 0 Lance,Eldon S. 96594 80 Domestic Stock 295 Frazier,Richard M* 109201 30 Stock 340 *Mr.Frazier is the landowner for the majority of the Delta Paving property Refer to Appendix G-2 for a Groundwater Monitoring Plan. 7.1 . Groundwater — Mining Mining activities will expose groundwater throughout the life of the mine. Pit dewatering will take place in the active pit to bring the groundwater table below the operating floor. This allows mining equipment to safely and effectively extract the material at the site. The pit pump will be active throughout the entire mining season, typically mid-April to early-November, depending on weather. It will be turned off during flood events or when temperatures drop below freezing. Pit dewatering will intercept groundwater from the alluvial aquifer of the Gunnison River that enters the pit to be routed back to the Gunnison River via the Relief Ditch after settling in the settling pond. The typical pump setup within each pit and discharge point are mapped on Map C-2. The pit pump will be a mobile pump with a diesel generator. The generator has an onboard fuel tank which will have secondary containment. The pump will typically be located two feet below the active mining floor at the lowest point of the pit. It will be surrounded by a gravel filter. This configuration minimizes the sediment being pumped out of the pit. Pumped water will be transported to the reclaimed lake which acts as a settling pond to prevent sediment from being discharged back into the river. This system of dewatering is proven to successfully return the water from the mining operations to the Gunnison River while trapping sediment on site. Delta Paving Gravel Pit G-7 Lewicki&Associates September 2022