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concentrations in backfill well GF -7 overall gradually declined in 2010 and 2014. The water levels <br />for the last few years have been fairly similar in well GF -7, indicating that these changes are not due <br />to new backfill being saturated but likely due to variations in recharge. Sulfate concentrations have <br />stayed low and steady in backfill well GF -5 in 2014. These small changes may be defining the very <br />small effects of upgradient mining but the changes are well within natural ranges. This monitoring <br />indicates that if the HI aquifer has been affected in these wells by upgradient mining, it has been very <br />small. <br />Sulfate concentrations in well GMP -1, which are shown on Figure B -12, have been highly <br />variable indicating an increasing trend during 2006 and 2007 and an overall similar increasing trend <br />in 2008 through 2014. The water level in well GNP -1 had been steadily increasing for several years <br />prior to becoming fairly steady in 2002, then gradually increasing for several years prior to being <br />steady the last three years. Sulfate concentrations may stay higher and variable in this well for <br />several years. Sulfate concentrations in this well should be influenced by the sulfate concentrations <br />in the backfill aquifer upgradient of GMT -1. The sulfate concentrations in well GP -3 had shown a <br />gradual increasing trend but concentrations have been steady the last twelve years. Overall steady <br />sulfate concentrations have been observed in well GP -7. Sulfate concentrations in eastern HI aquifer <br />well GC -1 have been similar to the previous higher values in well GMP -1 and had to be natural until <br />the last few years. Therefore, a sulfate concentration of at least greater than 600 mg/1 is needed to <br />indicate that the increases may be due to the mining operation. The 2014 value from well GC -1 was <br />similar to past values. <br />Figure B -13 presents the sulfate concentrations for three 3rd White Sandstone wells. The <br />previous eleven years of sulfate values from well P -8 had overall gradually decreased while the 2012 <br />and 2014 values overall slightly increased. The magnitude and timing of the prior increase in sulfate <br />Trapper Mining Company 3 -6 <br />2014 Annual Report <br />