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6.4.7 EXHIBIT G -Water Information <br />3. The Mine and Reclamation Plan Maps show the locations of five (5) groundwater monitoring <br />wells and the approximate location of the slurry wall surrounding the Phase 2 & 3 Areas. Please <br />clarify the minimum distance of the monitoring wells from the slurry wall. Please respond. <br />4. The Division has requested that the Applicant provide baseline water level data already <br />collected. In addition, the Applicant will need to demonstrate how they will provide five (5) <br />quarters of baseline water level data from the monitoring wells prior to exposure of groundwater <br />at the Wallenberg West Pit. If 5 quarters of data has not already been collected, the Applicant <br />may commit to sampling and submittal of such data prior to exposure of groundwater at the site. <br />Further, the Applicant will need to describe how the baseline data collected from the 5 wells will <br />be synthesized to establish baseline groundwater elevation(s) prior to exposure of groundwater at <br />the site. Please respond. <br />5. In conformance with Rule 3.1.6(1), please quantify the maximum pumping rate and duration <br />of pumping expected for de-watering activities in the 10-acre Phase 1 Area; and quantify the <br />horizontal and vertical extent of drawdown expected from de-watering activities at the time of <br />maximum excavation. In addition, the Division requests that the Applicant provide a <br />representative cross-sectional diagram that shows the Phase 1 Pit at maximum excavation, static <br />groundwater level and expected drawdown, and location of any well or groundwater user within <br />the radius of drawdown. Finally, based on the results of the drawdown analysis, please provide <br />a Map or Exhibit which shows the location(s) of all groundwater users within the radius of <br />expected drawdown during a time of maximum disturbance. The Map or Exhibit should also <br />include all available data on each well such as well completion, well type, well depth, well <br />registration number, pumping rate, baseline water level, etc. Please respond. <br />6. In accordance with Rule 3.1.6(1), please provide an assessment ofpossible hydrologic impacts <br />to the Brighton Ditch based on planned de-watering activities at the Wattenberg West Pit. <br />Information to be included in the assessment should include, but not be limited to the following: <br />• Ownership of the ditch. <br />• Is the ditch lined or unlined? <br />• What is the annual flow regime of the ditch? <br />• Is the ditch hydrologically connected to the shallow alluvial aquifer? <br />• Average seepage losses in the reach extending from WCR 4.5 to WCR 6. <br />• Schematic showing the elevation of the ditch, ditch invert, ditch water level, ground <br />surface elevation at Phase 1, and groundwater elevation at Phase 1. <br />7. In accordance with Rule 6.4.7(2)(b), please characterize the shallow alluvial aquifer and <br />include a discussion of the direction and rate of groundwater movement in the Wattenberg West <br />project area and surrounding area. Please respond. <br />8. In accordance with Rule 6.4.4(f)(i), please verify the maximum depth of excavation and the <br />substrate at the pit bottom, ie: shale, clay, claystone, sandstone, ect. In addition, please provide a <br />representative cross-sectional diagram which shows the width and depth of slurry wall <br />