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Requirement <br />Regulation <br />Reviewed <br />Comment <br />hydrogeologic and water quality factors (e.g., concentrations <br />of TDS and sulfate) indicate that coal spoil leachate has not <br />reached GP -9. <br />Flume Gulch alluvium could also be contaminated by coal <br />spoil leachate. The Coy well is the ground water point of <br />compliance for the Flume Gulch alluvium, as explained on <br />page 4 -242 of the permit application. Data from the Coy <br />well in 2013 indicate no exceedances of the Basic Standards <br />for Ground Water for the classification of agricultural use. <br />Up- gradient alluvial monitoring well GC -3 has shown <br />variation of TDS and Sulfate levels over the many years of <br />monitoring. However, TDS and Sulfate levels found in <br />2013 are higher than the ranges of values found during the <br />baseline studies contained in Sections 2.7.5.2 of Trapper's <br />permit for Well GC -3. TDS levels in the Coy well seem to <br />be consistently higher than the levels reported for well GC- <br />3. <br />The iron (Fe) levels reported for alluvial monitoring well P- <br />1 have varied throughout the years, however in September <br />of 2011 and September of 2013 the levels were reported to <br />be 133 and .72 mg /1 respectively. These levels are higher <br />than the Colorado Department of Health and Environment <br />Water Quality Control Commission, Regulation No. 41, The <br />Basic Standards for Ground Water, Table II standard for <br />Iron which is 3 mg /1. Previous monitoring data for this well <br />show iron levels to be below this standard except for one <br />event in September of 1999 when a level of 1.24 mg /1 was <br />reported. This impact is not addressed in the 2013 Annual <br />Hydrology Report narrative. The Division requested that <br />Trapper address this issue in an adequacy review letter sent <br />on April 24, 2014. On July 17, 2014 the Division received a <br />response from Trapper and they believe the iron levels <br />found at this well are within their natural range. They also <br />state that there is no indication of any outside factors <br />affecting the iron levels at this well and that this well is <br />completed in a shallow aquifer and may be easily be <br />manipulated by dry period and lower water levels. <br />Page 6 <br />