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Well Number Increasing Trends Decreasing Trends
<br /> AMW-2 Nitrate-N,Specific Conductance None Apparent
<br /> AMW-6 Barium,Bicarbonate,Chloride,Nitrate-N, None Apparent
<br /> Strontium
<br /> AMW-7 Bicarbonate,Chloride,Magnesium, None Apparent
<br /> Nitrate-N,Specific Conductance,Sulfate,
<br /> TDS
<br /> AMW-12 Bicarbonate Calcium,Chloride,Magnesium,Strontium
<br /> AMW-13 Bicarbonate Nitrate-N
<br /> AMW-14 Barium,Calcium,Magnesium, Specific Conductance,TDS
<br /> Potassium,Sodium,Strontium
<br /> There were no constituents that exhibited a statistically significant increasing trend
<br /> during the third quarter 2008 monitoring event and also exceeded their concentration
<br /> limits.
<br /> 3.1.5 Corrective Action Program
<br /> Field and laboratory results for CAP wells for the third quarter 2008 monitoring period
<br /> are summarized in Table 3-2. Data were graphed on time-series concentration plots by
<br /> Herst & Associates from data collected through the third quarter 2008, and are presented
<br /> in Appendix D. As shown in Table 3-2, 15 VOCs were detected in CAP wells during the
<br /> current monitoring period. Well -1 had the greatest number of VOCs(12),
<br /> including five measured above the PQL.
<br /> Awk
<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 Sen's Slope trend analyses
<br /> to determine if significant increasing or decreasing trends were evident in the data. Trend
<br /> analyses,performed by Herst&Associates, are presented in Appendix D and are
<br /> 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. As shown in the following table, significant increasing trends were calculated for
<br /> one or more VOC constituents in CAP wells AMW-1, AMW-10, and AMW-19, while
<br /> decreasing VOC trends were noted in CAP wells AMW-1, AMW-4, AMW-10, and
<br /> AMW-11.
<br /> Well Increasing Trends Decreasing Trends
<br /> Number
<br /> AMW-1 Barium,Bicarbonate,Specific Nitrate-N,pH,Sulfate,DCDFM
<br /> Conductance, 1,1-DCA,cis-1,2-DCE,
<br /> Vinyl Chloride
<br /> AMW-3 None Apparent None Apparent
<br /> AMW4 Nitrate-N Chloride,Barium,Bicarbonate,Calcium,
<br /> Magnesium,Potassium,Sodium,
<br /> Strontium,Specific Conductance,TDS,
<br /> 1,1-DCA,DCDFM,PCE,Vinyl Chloride
<br /> n: OO1OWA_3Qoauoc
<br /> 12 Geologic Associates
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