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3.0 GROUND-WATER QUALTTY <br />Appendix B presents the ground-water quality data for Trapper Mine. Table B-1 (page <br />B-41) tabulates the available ground-water quality data for Trapper monitoring wells. Field <br />conductivity was selected as the primary parameter to discuss trends of major constituents. <br />3.1 FIELD CONDUCTIVITY <br />The 1988 Annual Hydrologic Report included TDS and field conductivity time plots. <br />Since 1989, all annual reports have presented only conductivity plots because conductivity reflects <br />the same changes in individual wells that could be seen on TDS plots with few outliers. <br />Conductivity is a good indicator of TDS and some major constituent concentrations, and is routinely <br />used for this purpose. Figures B-1 through B-39 present both field and laboratory conductivity <br />versus time for each well. <br />Figures B-1 and B-2 present the conductivity versus time plots for wells GA1 and GA2. <br />The conductivity from well GAI exhibits significant fluctuations over a range from 880 to 1440 <br />µmhos/cm excluding one outlier. The general trend is steady to slightly declining. Well GA2 is <br />located near GA1 and screened in the interval immediately above the GAl completion. Its <br />conductivity increased compared to those values observed in 1993 but similaz to earlier volumes. <br />Well GA2 went dry after the second quarter and remained thY throughout the remainder of 1994. <br />With the exception of the 3rd quarter field reading, conductivities presented on Figure <br />B-3 present a fairly steady plot of conductivity for well GB2. The 3rd quarter field value is roughly <br />twice that of the laboratory value, and is thought to be an error. The TDS does not indicate a <br />significant change. The 3rd quarter laboratory value fits the existing trend. Figure B~ presents the <br />i <br />3-1 <br />