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Exhibit G presents a discussion of the surface and ground water systems in more detail. A MODFLOW <br /> ground water model was used to investigate changes to the water balance as a result of the mine <br /> development and dewatering and indicates dewatering rates ranging from approximately 80 to 55 gpm. <br /> Actual dewatering rates will likely vary with precipitation, will be impacted by the local geology and <br /> these rates should be considered potential average dewatering rates from the mine. It is expected that <br /> dewatering rates will higher when the mine is developed, encounters ground water and dewatering <br /> operations are initiated. Dewatering rates are expected to decline as the mining and dewatering <br /> continues. If the fractures encountered by the mine are not connected or have a low level of <br /> interconnectedness,the fractures may drain over time and the dewatering rates could drop to minimal <br /> amounts. <br /> Dewatering rates of 80 to 55 gpm equate to discharges of approximately 0.35 to 0.24 acre-feet per day. <br /> These discharge rates are lower than the average precipitation amounts which are not adequate to <br /> sustain live flow in the dry creeks so the discharge of mine dewatering water is not expected to result in <br /> live flow conditions in the gulches during mine operation. Mine discharge will infiltrate the gulch <br /> streambeds back to the ground water system downstream from the mine property. <br /> No water quality samples have been collected from the surface water monitoring locations on Windy <br /> and Dawson Gulch as part of the monitoring because there has been no flow to sample since the <br /> monitoring locations were established. The locations of the ground and surface water monitoring <br /> locations are presented in Figurel. Baseline water quality data is provided in Appendix K. <br /> 6.4.21(12)Water Quality Monitoring Plan <br /> The AMEC OMS Manual in Appendix F includes water quality monitoring plan specific to the FTSF. <br /> The water quality constituent that has regularly been identified as exceeding water quality standards at <br /> the site is manganese from the ground water system, based on the past water quality testing from the <br /> monitoring wells. There is the potential that, once dewatering commences,the water quality of the <br /> discharge water could be different than indicated by the monitoring wells. We will not know the actual <br /> quality of the mine dewatering water until the mining and dewatering operations commence. <br /> Zephyr will continue to monitor the water quality at the surface monitoring points on each of the <br /> drainages that cross the property and ground the water monitoring points in both of the identified <br /> aquifers beneath the property as mining commences and progresses. Future results will be compared to <br /> the baseline quality already collected and currently being collected. The water quality of the mine <br /> discharge will also periodically be tested <br /> Water quality monitoring results will be reported in annual reports including 1)the location of sampling, <br /> 2) a water level or description of flow conditions and 3)the results of the water quality testing. Water <br /> quality monitoring is currently and will continue to be performed on a quarterly basis throughout the <br /> mine life and continue for at least 8 quarters after mine closure unless water quality parameters drop to <br /> a level such that a lesser frequency is justified. <br /> The water quality monitoring plan includes/will include surface and ground water monitoring points <br /> both up and down gradient from the mine site so that all impacts can be monitored. <br /> 76 <br />