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U <br />evaluated using Mann -Kendall / Sen's Slope trend analyses to determine if significant <br />increasing or decreasing trends were evident in the data. Trend analyses, performed by <br />Herst & Associates, are presented in Appendix D and summarized below. Wells and <br />analytes not discussed below either do not show significant trends (rising or falling) or <br />have too few data points to establish meaningful trends. <br />Well Number <br />Increasing Trends <br />Decreasing Trends <br />AMW-2 <br />Bicarbonate, Nitrate -N, Specific <br />None Apparent <br />Conductance <br />AMW-6 <br />Barium, Chloride, Magnesium, Nitrate -N, <br />None Apparent <br />Specific Conductance, Strontium, Total <br />Dissolved Solids (TDS) <br />AMW-7 <br />Bicarbonate, Calcium, Chloride, <br />Potassium <br />Magnesium, Nitrate -N, Specific <br />Conductance, Sulfate, TDS <br />AMW-12 <br />None Apparent <br />Calcium, Chloride, Magnesium, Strontium <br />AMW-13 <br />Bicarbonate <br />Nitrate -N <br />AMW-14 <br />Barium, Calcium, Hexavalent Chromium, <br />DCDFM, PCE, TCE <br />Magnesium, Nitrate -N, Potassium, <br />Sodium, Strontium, Sulfate <br />With the exception of barium concentrations measured in well AMW-14, no constituents <br />that exhibited a statistically significant increasing trend during the third quarter 2011 <br />monitoring event also exceeded their concentration limits. The third quarter 2011 barium <br />concentration measured in the sample collected from well AMW-14 (0.270 mg/L) is <br />within the historical range of values observed at this well, and is well below the state <br />primary drinking water standard (1 mg/L). <br />3.1.5 Corrective Action Program <br />Field and laboratory results for CAP wells for the third quarter 2011 monitoring period <br />are summarized in Table 3-2. As shown in Table 3-2,14 VOCs were detected in CAP <br />wells during the current monitoring period. Well AMW-1 had the greatest number of <br />VOCs (13), including seven measured above the PQL. <br />In order to evaluate the effectiveness of corrective action measures, particularly with the <br />groundwater treatment facility (GTF), trend analyses were performed for CAP wells at <br />the Austin Unit, beginning in 1994 when the GTF began operation. The observed <br />groundwater quality constituent trends were evaluated using Mann -Kendall / Sen's Slope <br />trend analyses to determine if significant increasing or decreasing trends were evident in <br />the data. Trend analyses, performed by Herst & Associates, are presented in Appendix D <br />and are summarized below. Wells and analytes not discussed below either do not show <br />significant trends (rising or falling) or have too few data points to establish meaningful <br />trends. <br />C:\2011-0050\FA_3QI I.doex 10 Geo -Logic Associates <br />