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Sampling was attempted using a generator but the well was deemed not functional. TCS-1 was <br />refurbished in the fall of 2005 and sampled thereafter. <br />Ground water sampling is performed in accordance with EPA approved methods and <br />instrumentation. The ground water quality at the Edna Mine is monitored via the parameters, <br />locations and frequency listed in Table 4.6-54, Section 4.6.8.4 of the permit. Analyses results for <br />monitoring wells TR-1.5, TR-3, TR-4, WR-1 and TCS-1 are found in Tables 8, 9, 10, 11 and 12. <br />Results of the analyses are discussed below. <br />4.2.1 Ground Water Temperature <br />Chart 22 shows temperature values for monitoring welils TR-1.5, TR-3, TR-4, WR-1 and TCS-1 <br />for the period of record. Temperature exhibited the same trends in 2009 as found during baseline <br />studies and previous years monitoring. Specifically, patterns in temperature are seasonal, <br />warming until July or August and than cooling throughout the remaining sampling season. The <br />amount of temperature fluctuation in Well TR-4 has been historically somewhat greater than <br />expected suggesting the flow to the perched aquifer, although subsurface, is very shallow. The <br />lowest temperature in 2009 was recorded at monitoring well TR-3 in May with a reading of 7.1 <br />°C and the high was recorded at monitoring site TR-1.-i in July with a reading of 15.2 °C. <br />4.2.2 Ground Water pH <br />Chart 23 shows pH concentrations for monitoring wells TR-1.5, TR-3, TR-4, WR-1 and TCS-1 <br />for the period of record. Values of pH during 2009 remained relatively constant over the <br />monitoring period. There is no apparent trend regarding pH. Overall, the groundwater has <br />' tended to be alkaline throughout the period of record. The lowest pH value in 2009 was recorded <br />at monitoring well TR-1.5 in August with a reading of 6.75 standard units and the high was <br />recorded at monitoring well TCS-1 in August with a reading of 8.42 standard units. <br />4.2.3 Ground Water Specific Conductivity and Total Dissolved Solids <br />Charts 24 and 25 show specific conductivity and TDS concentrations for monitoring wells TR- <br />1.5, TR-3, TR-4, WR-1 and TCS-1 for the period of record. Specific conductivity and TDS <br />' values for the three alluvial wells have remained fairly constant over the'majority of the period of <br />record. While specific conductivity and TDS values at sites TR-3 and TR-4 are consistent with <br />values obtained during the baseline studies, these parameters and several others have elevated <br />' rapidly and remained elevated at TR-1.5 since 1995. The source of the elevated values is not <br />readily identifiable. A few factors which may have contributed to the elevated values were <br />mentioned in the 1996 Report (i.e., inundation of the axea in late spring of 1995 and the laying of <br />' telephone cable immediately upstream of the area during the summer of 1995). If the elevated <br />values resulted from those activities, the values should have returned to more historic levels <br />during the past decade. However, the values have! remained elevated. It appears that the <br />??WWCENGIN6ERING rage 12