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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 2010 monitoring period
<br /> are summarized in Table 3-2. As shown in Table 3-2, eight VOCs were detected in CAP
<br /> wells during the current monitoring period. Well AMW-1 had the greatest number of
<br /> VOCs (seven), including six 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 /> Well Increasing Trends Decreasing Trends
<br /> Number
<br /> AMW-1 Barium,Bicarbonate,Specific Nitrate-N,pH,Sulfate,DCDFM
<br /> Conductance, 1,1-DCA,
<br /> cis-1,2-DCE
<br /> AMW-3 None Apparent None Apparent
<br /> AMW-4 pH,Nitrate-N Barium,Bicarbonate,Calcium,Chloride,
<br /> Magnesium,Potassium,Sodium,Specific
<br /> Conductance,Strontium,TDS,cis-1,2-DCE,PCE,
<br /> TCE
<br /> AMW-5/5R Barium,Bicarbonate,Chloride, None Apparent
<br /> Nitrate-N,pH,Potassium,
<br /> Sodium,Specific Conductance,
<br /> Sulfate,TDS
<br /> AMW-10 Sulfate,cis-1,2-DCE Barium,Bicarbonate,Calcium,Chloride,
<br /> Magnesium,Nitrate-N,Potassium, Sodium,
<br /> Strontium,TDS, 1,1-DCA,DCDFM,PCE,TCE
<br /> AMW-11 None Apparent Bicarbonate,Calcium,Chloride,Magnesium,
<br /> Potassium,Specific Conductance,TDS, 1,1-DCA,
<br /> cis-1,2-DCE,DCDFM,PCE,TCE
<br /> AMW-18 Bicarbonate, Strontium Chloride,Nitrate-N,Potassium, Sodium,Sulfate,
<br /> TDS
<br /> AMW-19 PCE,TCE Hexavalent Chromium,Nitrate-N, Sodium,
<br /> Sulfate,TDS
<br /> ANIW-19BR PH Nitrate-N, Potassium, Sulfate
<br /> As shown in the table above, significant increasing trends were calculated for one or
<br /> more VOC constituents in CAP wells AMW-1, AMW-10, and AMW-19, while one or
<br /> more decreasing VOC trends were noted in CAP wells AMW-1, AMW-4, AMW-10, and
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