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For VOCs, only those VOCs that exhibited detections for the fourth quarter 2007 monitoring event were plotted. Historical data from the corrective action monitoring wells from March 1994 to the present were analyzed for temporal trend using Sen's Slope trend analysis. Graphs of the Sen's Slope analyses for corrective action monitoring wells are included in Appendix G. Table 2.4 summarizes the results of the corrective action monitoring well trend analysis. The following inorganic constituents exhibited an increasing trend according to the Sen's Slope analysis:barium at AMW- 1, AMW-5R, and AMW-18, bicarbonate at AMW-1, AMW-5R, and AMW-18, chloride at AMW-5R, nitrate at AMW-5R, field pH at AMW-5R, sodium at AMW-11, field specific conductance at AMW-1 and AMW-5R, sulfate at AMW-5R and AMW-10,TDS at AMR-5R, and field turbidity at AMW-10 and AMW-19. The fourth quarter 2007 concentration of barium at AMW-1 (0.36 mg/L) is comparable to concentrations observed at that well intermittently since May 2004, and is well below the National Primary Drinking Water Standard (2 mg/L). The fourth quarter 2007 concentration of barium at AMW-5R (0.39 mg/L) is greater than concentrations previously observed at AMW-5. The fourth quarter 2007 concentration of barium at AMW-18 (0.17) is comparable to concentrations observed at that well intermittently since August 2005, and is well below the National Primary Drinking Water Standard(2 mg/L). The fourth quarter 2007 concentration of bicarbonate at AMW-1 (800 mg/L) is comparable to concentrations observed at that well intermittently since August 2003. The fourth quarter 2007 concentration of bicarbonate at AMW-5R (530 mg/L) is greater than concentrations previously observed at AMW-5. The fourth quarter 2007 concentration of bicarbonate at AMW-18 (340 mg/L) is comparable to concentrations observed at that well consistently since November 2004. The fourth quarter 2007 concentration of chloride at AMW-5R (110 mg/L) is comparable to concentrations previously observed at AMW-5, and is below the National Secondary Drinking Water Standard (250 mg/L). The fourth quarter 2007 concentration of nitrate at AMW-5R (28 mg/L)is greater than concentrations previously observed at AMW-5. The field pH value observed at AMW-5R during the fourth quarter 2007 (6.81 s.u.)is comparable to pH values observed at AMR-5 intermittently since August 1993, and is within the National Secondary Drinking Water Standard range (6.5 - 8.5 s.u.). The fourth quarter 2007 field concentration of sodium at AMW-11 (75 mg/L) is comparable to concentrations observed at that well since August 2006. The fourth quarter 2007 field specific conductance value at AMW-1 (1,370 umhos/cm) is comparable to values observed at that well consistently since August 2005. The fourth quarter 2007 field specific conductance value at AMW-5R (1,370 umhos/cm) is comparable to values observed at that well intermittently since November 2003. The fourth quarter 2007 concentration of sulfate at AMW-5R (65 mg/L) is comparable to concentrations observed at AMW-5 consistently since July 2001, and is well below the National Secondary Drinking Water Standard (250 mg/L). The fourth quarter 2007 concentration of sulfate at AMW-10 (72 mg/L) is comparable to concentrations observed at that well since May 2006, and is well below the National Secondary Drinking Water Standard (250 mg/L). The fourth quarter 2007 concentration of TDS at AMW-5R(810 mg/L) is greater than concentrations previously observed at AMW-5. The field turbidity value observed at AMW-10 (12 NTUs) is comparable to field turbidity values observed at that well since July 1998. The field turbidity value observed at AMW-19 during the fourth quarter 2007 (>999 NTUs) is consistent with the field turbidity observed at that well during the past four monitoring events. 4