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concentration of cis-1,2-dichloroethene at AMW-13 (1.5 ug/L) is comparable to concentrations observed at that well intermittently since November 2003, and is well below the National Primary Drinking Water Standard (70 ug/L). The first quarter 2008 concentration of dichlorodifluoromethane at AMW-13 (1.7 ug/L) is comparable to concentrations observed at that well intermittently since April 1995. The first quarter 2008 concentration of dichlorodifluoromethane at AMW-14 (1.0 ug/L) is comparable to concentrations observed at that well intermittently since May 1996. The first quarter 2008 concentration of tetrachloroethene at AMW-13 (25 ug/L) is comparable to concentrations observed at that well intermittently since September 1996, and is above the National Primary Drinking Water Standard(5 ug/L). The first quarter 2008 concentration of tetrachloroethene at AMW-14 (18 ug/L) is comparable to concentrations observed at that well intermittently since March 1996, and is above the National Primary Drinking Water Standard (5 ug/L). The first quarter 2008 concentration of trichloroethene at AMW-13 (7.1 ug/L) is comparable to concentrations observed at that well intermittently since November 2003, and is above the National Primary Drinking Water Standard (5 ug/L). The first quarter 2008 concentration of trichloroethene at AMW-14 (1.3 ug/L) is comparable to concentrations observed at that well intermittently since March 1996, and is below the National Primary Drinking Water Standard (5 ug/L). The first quarter 2008 concentration of trichlorofluoromethane at AMW-13 (0.79 ug/L) is comparable to concentrations observed at that well intermittently since November 2000. Historical data from the detection monitoring wells were analyzed for temporal trend using Sen's Slope trend analysis. Graphs of the Sen's Slope analyses for detection monitoring wells are included in Appendix E. The following inorganic constituents exhibited an increasing trend according to the Sen's Slope analysis: barium at AMW-6 and AMW-14, bicarbonate at AMW-6, AMW-7, AMW-12, and AMW-13, calcium at AMW-14, chloride at AMW-6 and AMW-7, magnesium at AMW-14, nitrate at AMW-2, AMW-6, and AMW-7, potassium at AMW-14, sodium at AMW-14, field specific conductance at AMW-7, strontium at AMW-14, sulfate at AMW-7, and TDS at AMW-7. Two constituents that exhibited a statistically significant increasing trend during the first quarter 2008 also exceeded their concentration limits: barium at AMW-14 and bicarbonate at AMW-13. Although there were increasing trends for nitrate at AMW-6 and AMW-7, background well AMW-2 also exhibited an increasing trend for nitrate during the first quarter 2008 monitoring event. Sen's Slope analysis identified decreasing trends in the following inorganic parameters: arsenic at AMW-6, calcium at AMW-12, chloride at AMW-12, magnesium at AMW-12, nitrate at AMW- 13, field specific conductance at AMW-14, strontium at AMW-12, TDS at AMW-14, and field turbidity at AMW-2. Of the organic constituents that were detected in detection monitoring wells during the first quarter 2008 monitoring event, only cis-1,2-dichloroethene at AMW-13 exhibited an increasing trend according to the Sen's Slope analysis. The first quarter 2008 concentration of cis-1,2- dichloroethene at AMW-13 (1.5 ug/L) is well below the National Primary Drinking Water Standard (70 ug/L). Dichlorodifluoromethane and trichloroethene at AMW-14 exhibited statistically significant decreasing trends according to the Sen's Slope analysis. 2.2 Corrective Action Monitoring Groundwater samples were collected by ATC Associates, Inc. from the corrective action monitoring wells (AMW-1, AMW-4, AMW-5R, AMW-10, AMW-1 1, AMW-18, and AMW-19) during the first quarter 2008 monitoring event. Corrective action monitoring well AMW-5R is a replacement for corrective action monitoring well AMW-5. ATC Associates, Inc. reported that 3