Laserfiche WebLink
and the infiltration to groundwater at this elevation would be expected to be in the order of 10% <br /> of this total, or 2 inches per year. This is equivalent to 0.1 gallons per minute per acre of area. <br /> Groundwater in the vicinity of the Millsite exists in a low permeability/low yield system typical <br /> of the granitic rocks of the Front Range. Yield of wells completed in the bedrock in this area is <br /> small; typically, a few gallons per minute at most. According to this report, the groundwater table <br /> is a muted reflection of the ground surface, and it intersects the ground surface in the deeper <br /> gulches and creeks. The Times Mine and the Wynona Mines are near the highest part of Horsfal <br /> Flat, where the groundwater water table is much lower than the steeper areas found in Lickskillet <br /> and Cash Gulches. <br /> The general quality of the groundwater in the granitic country rock is good, as reflected in the <br /> water quality samples taken from the wells that are downgradient of the Millsite;while the ambient <br /> groundwater quality in the mineralized veins and fissures in the mines is of substantially lower <br /> quality. The groundwater found in the mines generally contains higher concentrations of sulfate <br /> and some metals, notably iron, manganese, and zinc that are elevated above that found in the <br /> groundwater in the granitic country rocks. The absence of any elevated sulfate or the presence of <br /> higher concentrations of these metals in any of the analyses of the water samples taken from these <br /> monitoring wells indicates that the water stored in these mines for more than thirty years is not <br /> flowing out of the mine workings. This confirms that the water stored in the Times and Wynona <br /> Mines is not migrating from these mines into any of these downgradient monitoring wells. <br /> As part of the Comprehensive Water Monitoring Plan for the Cash Mine,a monitoring well located <br /> downgradient to the Gold Hill Mill was selected to monitor the quality of water in this area. This <br /> monitoring well is one-hundred and eighty-eight(188)feet deep and it was drilled in solid granitic <br /> country rock. The depth to groundwater ranges between fifteen (15) feet and thirty-five (35) feet. <br /> CMC has been sampling the groundwater in this well on a quarterly basis since it became the <br /> permitted operator of the Gold Hill Mill and the Cash Mine.Nothing has ever been detected in this <br /> downgradient monitoring well that would indicate that the water contained in the Wynona Mine <br /> workings was affecting the water quality in this area. This confirms the impermeable nature of the <br /> granitic country rocks surrounding the Times and Wynona mines. <br /> 9 <br />