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Sulfate concentrations in well GMT-1 have been highly variable but showing no long -term <br />trend. The water level in well GMP -1 had been steadily increasing for several years prior to <br />becoming fairly steady in 2002. Overall the water levels have been steady the last few years. <br />Sulfate concentrations may stay variable even with the steady water level. Sulfate concentrations in <br />this well should be influenced by the sulfate concentrations in the backfill aquifer upgradient of <br />GMP -1. The sulfate concentrations in well GP -3 had shown a gradual increasing trend but <br />concentrations have been steady the last four years. Overall steady sulfate concentrations have been <br />observed in well GP -7. Sulfate concentrations in eastern HI aquifer well GC -1 have been similar to <br />the higher values in well GMP -1 and had to be natural until the last few years. Therefore, a sulfate <br />concentration of at least greater than 600 mg/1 is needed to indicate that the increases may be due to <br />the mining operation. The second 2006 value from well GMP -1 increased to above this level. <br />Figure B -14 presents the sulfate concentrations for four 3rd White Sandstone wells. The <br />last six years of sulfate values from well P -8 have gradually decreased after a large increase over <br />five years. The magnitude and timing of the sulfate concentrations in well P -8 indicate that this <br />increase is due to mining The sulfate changes in wells GC -2 and GP -9 are within the natural range <br />of concentrations for this aquifer. Figure B -15 presents the sulfate concentrations for wells GE -3, <br />GLUX -1 and P -5. The sulfate concentrations for GLUX -1 have remained low. Well P -5 was dry <br />the last five years. The sulfate concentrations in well P -5 are natural and show that relatively high <br />values naturally exist in this sandstone. <br />Figure B -16 presents the sulfate concentrations for wells GC -3, P -1, P -3, J -1 and COY. The <br />sulfate concentrations in alluvial well P -1 declined in 2006 after high values over the last few years <br />at levels within historical natural values for this well. The Lewis Shale well P -3 was dry during <br />Trapper Mining Company 3 -7 <br />2006 Annual Report <br />