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The only water quality parameter that is detected regularly in the ground water monitoring wells as an <br /> exceedance of the Regulation 41 limits is manganese. Iron and pH have also exceeded Regulation 41 <br /> standards, but only periodically. The manganese exceedance was only observed in the North Well. <br /> Manganese is very common in soils and sediments and is commonly found with iron as a mineral oxide. <br /> When water interacts with these oxides they are dissolved and mobilized by the water. At the levels <br /> identified by the monitoring program,the water quality will likely result in aesthetic staining but not <br /> health concerns. <br /> Ground water in the geologic material to be mined at the Dawson property mine is contained almost <br /> entirely in fractures in the bedrock material. The ground water flows through these minute fractures <br /> from the infiltration of local precipitation or regional underflow. This ground water system is contained <br /> in the Precambrian material targeted by the mine. No sedimentary geologic material will be mined <br /> during the mining process, but areas over sedimentary units will be disturbed. The Dakota formation <br /> has locally been identified as a saturated aquifer. The Precambrian ground water system will be strongly <br /> influenced by the dewatering of the mine once ground water is encountered and dewatering <br /> commences. The ground water that enters the mine will enter through the fractures that intersect the <br /> mine workings and inflows will be controlled be the characteristics of those fractures.The neighboring <br /> sedimentary aquifer will be impacted to a lesser extent due to the distance and separation from the <br /> mine dewatering by local faulting. <br /> Regional ground water gradients in the ground water aquifer systems are generally towards the north in <br /> the Precambrian material from the mountainous areas south of the mine and towards the <br /> east/northeast in the Dakota formation towards the center of the Canon City Embayment. <br /> Local recharge sources to the ground water systems are mainly limited to precipitation that infiltrates <br /> the formations either as direct recharge or along drainages during runoff where they are present at the <br /> surface. Windy and Dawson Gulch appear to be out of connection with the ground water system, but <br /> Grape Creek to the north of the mine area appears to be locally in connection with the Precambrian <br /> material draining the Precambrian material immediately adjacent to it. <br /> Three ground water wells were identified within approximately 1 mile of the mine workings. One of the <br /> wells may be mislocated, one is completed in the Precambrian material but is separated from the mine <br /> workings by faulting and one is completed in the Dakota separated from the mine workings by faulting. <br /> Based on the locations of the wells and the regional faulting,the drawdown required for the mining <br /> should not impact the nearby ground water wells. <br /> 6.4.21(9) Ground Water Quality Data <br /> Ground water quality samples have been collected as part of the planning efforts for the proposed mine. <br /> Two monitoring wells (North Well and South Well)were constructed at the proposed mine site to allow <br /> for the observation of water levels over time and the collection of water quality samples. The <br /> monitoring wells are located as presented in Figure 1. Water quality samples of mine inflow have not <br /> been directly sampled because the mine does not exist at this time, but will be in the future. <br /> Water quality samples have been collected from the North and South Monitoring Wells which were <br /> analyzed for a suite of water quality parameters for four quarters between October 2014 and October <br /> 2015 to provide a full year of water quality data. Quarterly water quality sampling has again been <br /> 74 <br />