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Response to DRMS Adequacy Review (1) — Cotter JD -9 Mine Reclamation Plan Amendment <br />sandstone is estimated at 0.04 ft/yr. The mine workings where saturated <br />conditions are located are several hundred feet from the existing monitoring <br />well. Cotter considers the water quality in this well to be indicative of ambient <br />conditions for the Salt Wash sandstone in the area of the JD-9 ore deposit. Data <br />from the monitoring wells shows that ambient groundwater quality is extremely <br />poor. Solely on water quality conditions, the groundwater has no viable use for <br />domestic or agricultural uses. Several constituents are well over water quality <br />standards. <br />Another issue is the distribution of groundwater within the Salt Wash sandstone. <br />The occurrence of groundwater is sporadic in this formation as indicated by <br />mining operations that mine the same rock strata but do not always encounter <br />groundwater. Drilling a background well or a compliance well may or may not <br />encounter groundwater. Requiring additional wells if dry holes are encountered <br />would not be economically reasonable for protecting a highly questionable <br />resource. <br />29. Due to the waste rock containing constituents at levels higher than federal, state and <br />agricultural levels is any type of impermeable liner proposed below the waste rock pile to <br />prevent unpermitted discharges? <br />No liner is planned for the waste rock pile because the majority of the waste rock <br />pile is already in place. The EPP provides a solid case for the lack of any <br />impacts to the environment from the waste rock pile. The waste rock pile sits on <br />low permeable shales and mudstones of the Brushy Basin member of the <br />Morrison Formation. The lack of moisture, geochemical conditions, and low <br />unsaturated hydraulic conductivity values limit the mobility of any uranium <br />related constituents. Kearl (2005) conducted numerical modeling studies of the <br />transport of uranium related constituents from the waste rock pile. This <br />modeling report is provided in the application amendment. Using very <br />conservative assumptions that assumed a worse -case scenario, after 1000 years <br />the concentration of uranium would be 1 /1,000,000 of the initial concentration at <br />a depth of 200 feet below the pile. There is approximately 200 feet of the Brushy <br />WX <br />