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-3- <br />Please find below additional DRMS review team comments that need to be addressed. <br />1.1.1: "Surface water runoff contacting the waste rock piles will be kept on site and directed into one of two <br />retention basins." <br />Comment: Please describe the ultimate fate of the water in the retention basins. Are the basins evaporation ponds? <br />Will the water be treated? <br />5.0: "...the uranium element would be considered a designated chemical." <br />Comment: Uranium is a toxic-forming material, not a designated chemical, and there are differences in how it is <br />regulated. <br />5.1: "The pH of the material was found to be slightly basic with values around 7.65 - 7.0" <br />Comment: Please describe how the pH of the material was measured. <br />5.1: "The material contains sulfur as sulfate....." <br />Comment: Please describe how the mineralogy was determined. <br />5.1: "The materials also contain a certain amount of buffering capacity (as measured by alkalinity bicarbonate and <br />hardness) which would help abate any free acid." <br />Comment: Please describe how the buffering capacity, alkalinity bicarbonate, and hardness were determined. <br />6.1: "Waste rock dumps will remain on surface when mine life exhausts." <br />Comment: Operator must quantify to the extent possible how much waste rock will remain and how much will be <br />backfilled underground. Operator must ensure that ground beneath the proposed waste rock piles has no seeps or <br />springs or watercourses that might compromise hydrologic stability. Operator must also ensure that there are no <br />features on the ground that could compromise geotechnical stability. <br />6.1: "These dumps will be contoured to match existing topography covered with topsoil and reseeded." <br />Comment: Will there be any overburden available that can provide additional cover to the waste rock piles? <br />9.0: "If no water is encountered initially then a piezometer should be constructed to gather the required five <br />quarters of data. If ground water is detected in measurable amounts then the piezometers may need to be pulled <br />and water quality monitor wells constructed." <br />Comment: Removing piezometers is not recommended; they are too valuable and even if they are not generating <br />data now they may generate data at some time in the future. DRMS will require the piezometers to remain for the <br />life of the mine. After 5 quarters of data have been collected, DRMS staff in conjunction with the operator will agree <br />on a gradual step down of monitoring to annual sampling. <br />9.0: "If groundwater of significant presence (>1 gpm) is measured for two consecutive quarters, SPLP parameter <br />analysis for five quarters using a state certified laboratory will be performed..." <br />Comment: Please clarify the connection between ground water quality and the requirement for SPLP parameter <br />analysis. <br />9.0: Table 1. <br />Comment: Table 1 should be expanded to include the analytes in the guidance document. <br />11.0: "Off site discharge is not anticipated due to climatic conditions at the Mine. If an event occurs as defined in <br />the CDPS General Permit and discharge is required a pre-determined State Certified Laboratory will be employed to <br />analyze and report the data to Rimrock."