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Appendix N is the Jesik Dawson Mine Surface Water Management Report that includes design <br /> criteria and engineer diagrams for all stormwater control structures and surface water diversion <br /> channels. <br /> (f)Secondary Containment Facilities <br /> A Spill Prevention Control and Countermeasure Plan (SPCC)will be prepared upon approval of <br /> the Exhibits C and D of the application. <br /> 6.4.21(8) Ground Water Information <br /> The Dawson Property mine dewatering is estimated to potentially be as high as approximately 80 gpm <br /> initially, but will more likely only be on the order of 55 gpm, especially once the total depth of the mine <br /> has been reached and dewatered using ongoing dewatering operations. These projected rates may <br /> overestimate required dewatering rates if the fractures encountered by the mine are not significantly <br /> connected. If there is limited interconnectedness of fractures encountered by the mine, dewatering <br /> rates may be significantly less. Mine water will accumulate in the bottom portions of the mine and be <br /> pumped to the Dawson Property mine portal. This discharge will mostly be used within the mine <br /> facilities, but some will be discharged to the surface and is subject to Colorado Department of Public <br /> Health and Environment(CDPHE) discharge permits. Water pumped from the mine will ultimately be <br /> discharged to surface drainage systems after flowing through a sedimentation pond. The local stream <br /> drainages the sedimentation pond overflows to is a dry gulch locally named Dawson Gulch. Dawson <br /> Gulch is tributary to Grape Creek and the Arkansas River, but rarely flows with flow mostly limited to <br /> during and immediately after large precipitation events. <br /> Ground water quality samples have been collected as part of the planning efforts for the proposed mine. <br /> The quality of the ground water is generally favorable with regular exceedances of the accepted <br /> standard reported for only Manganese in the North Well. No water quality samples have been collected <br /> from the surface water monitoring locations as part of the monitoring because there has been no flow <br /> at the sampling location since the monitoring locations were established. The locations of the ground <br /> and surface water monitoring locations are presented in Figure 1. An additional monitoring well is <br /> proposed for the monitoring program as presented. <br /> Water quality samples have been collected from the North and South Monitoring Wells which were <br /> analyzed for a partial suite of water quality parameters for four quarters between October 2014 and <br /> October 2015 to provide a full year of water quality data. Quarterly water quality sampling has again <br /> been resumed starting in March of 2021 to confirm whether water quality conditions have changed over <br /> time (which would not be expected as mining has not occurred and the site has not changed). No <br /> surface water quality samples were collected over either period as the drainages did not run during that <br /> monitoring period. The water quality results are presented in Appendix K. <br /> 72 <br />