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Well 81-01 sulfate,manganese and iron concentrations were above <br /> the baseline water quality levels for this well and are also above the <br /> basic standards of groundwater. Calcium and chloride <br /> concentrations were above the baseline levels and below the basic <br /> standards for groundwater. Sodium levels are also above the <br /> baseline water quality levels. Magnesium concentrations were the <br /> highest ever recorded at this location. <br /> Regarding the Twenty Mile Sandstone;concentrations in Well 259 <br /> are within historic ranges and consistent with baseline water quality <br /> concentrations. <br /> The No. 9 Mine Well exhibitied the highest concentration of sulfate <br /> and was above the basic standards for groundwater. Magnesium, <br /> sodium,chloride,boron, and calcium concentrations were also the <br /> highest recorded. <br /> Regarding the Williams Fork Alluvium well AVF-3,concentrations <br /> were within the baseline water quality levels. Well AVF-5 exhibited <br /> sulfate concentrations above basic standards for groundwater and <br /> within historical ranges.Manganese and selenium concentrations <br /> were the highest measured in AVF-5. Only manganese was found <br /> to be above the basic standard of groundwater. However,the <br /> baseline levels were also above the standard. Well AVF-6 water <br /> quality was within historic concentration ranges. The MCM report <br /> states that no impact on alluvial water quality has occurred. <br /> MCM did not provide an explanation for any of the maximum <br /> concentrations observed in the wells mentioned above and the cause <br /> of the elevated concentrations remains unclear.Additional analysis <br /> may be warranted in the future to determine if they are mine <br /> related <br /> Section 4.05.13(1)of the Regulations requires the establishment of <br /> one or more ground water points of compliance(wells),for an <br /> operation possessing the potential to negatively impact ground water <br /> quality. It does not appear ground water points of compliance wells <br /> have been established for this site. However,the Middle Sandstone <br /> in well TR-7a and the Williams Fork alluvium in well AVF-5 are <br /> monitored. Well TR-7a is within the expected bedrock flow path of <br /> mine leachate, should the mine discharge leachate to bedrock units. <br /> The AVF-5 well is within the expected alluvial flowpath of leachate, <br /> should the mine discharge leachate to Williams Fork River <br /> alluvium. Both wells meet the qualifications of a compliance point <br /> as per qualifications listed in Section 4.05.13(1)(b)of the Rules. <br /> Monitoring data from both wells indicate the mine has likely not <br /> caused an exceedance of the Basic Standards for Ground Water. <br /> According to section 2.04.7 of the permit,for the Williams Fork <br /> Alluvium; dissolved solids,iron,lead,manganese and sulfate often <br /> exceed the drinking water standards naturally.Monitoring data does <br /> indicate that manganese levels in AVF-5 often exceed the drinking <br /> water limit. <br /> 20. Restoration of MCM turned off the mine pumps in July of 2013. Some wells <br /> ground water CDRMS reacted to the pumps being turned off. Water levels increased or <br /> recharge to regulation have remained stable in recent years. However,water levels in well <br /> approximate pre- 4.05.12(3) 83-03 continue to decrease. <br /> mining rate <br /> Page 4 <br />