2014-03-18_REPORT - C1981010 (5)

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3.0 GROUND - WATER- QUALITY Appendix B presents the ground -water quality data for the Trapper Mine. This appendix tabulates all of the historical data in Table B -1 and presents IDS and sulfate plots versus time to convey changes in the major constituent water quality. Appendix B also, presents the spring and seep water - quality data. Water quality for -the springs and seeps- are included in tliis section because their source is ground water. Section 3.7 presents a discussion of the spring and seep water - quality data. 3.1 TOTAL - DISSOLVED SOLIDS.(rDS)_ Figures B -1 through B -7 present plots of the TDS concentrations for the Trapper Mine- wells. The wells have been grouped together based on aquifers. Figure 9-1 presents the TDS concentrations versus time for two QR aquifer wells GD -2 and - GD -3. Well GD -3 is a, backfill well in the, QR aquifer. TDS concentrations had been fairly steady the previous eleven years in well GD=3 but have increased in 2010 and 2011 then declined in 2012 and slightly increased- in 2013. The fluctuation in this backfill aquifer is well - within natural ranges and may be very similar to variations that would have occurred in the QR aquifer at this location. Some of the TDS in the backfill aquifer may be due to leaching from the backfill material. The TDS in this backfill aquifer is greater than it is downgradient in the R Coal at GD -2 which increased. in -concentration in 2008 through 2012 but slightly declined in 2013. This could be the - movement of higher concentration from the GD -3 area to well GD -2. Figure B -2 also presents a group of three QR wells. Well GF -11 is an equivalent QR aquifer well.in the backfill. The 2013 TDS concentrations -were fairly steady in- backfill well GF -11 and is below its peak in 2001 and 2002. Concentrations in -the QR aquifer are monitored downgradient at Trapper Mining Company 3 -1 2013 Annual Report