### Drexel Water Treatment Plant, Missouri PWSID: MO1010225

Atrazine Concentration

Sample Date Raw Water Atrazine

(PPB) Raw Water Method of Analysis Finished Water Atrazine

(PPB) Finished Water Method of Analysis 24-Apr-06 1.67 LCMS-1 0.54 LCMS-1 2-May-06 0.81 LCMS-1 0.87 LCMS-1 8-May-06 0.93 LCMS-1 0.66 LCMS-1 15-May-06 1.46 LCMS-1 1.22 LCMS-1 22-May-06 0.89 LCMS-1 0.54 LCMS-1 30-May-06 1.17 LCMS-1 0.65 LCMS-1 7-Jun-06 2.02 LCMS-1 1.10 LCMS-1 12-Jun-06 1.19 LCMS-1 1.06 LCMS-1 19-Jun-06 0.79 LCMS-1 0.62 LCMS-1 26-Jun-06 1.48 LCMS-1 0.57 LCMS-1

5-Jul-06 1.10 LCMS-1 0.62 LCMS-1 10-Jul-06 0.94 LCMS-1 0.57 LCMS-1 17-Jul-06 0.98 LCMS-1 0.55 LCMS-1 24-Jul-06 1.12 LCMS-1 0.75 LCMS-1 17-Aug-06 0.87 LCMS-1 0.63 LCMS-1 28-Aug-06 0.61 LCMS-1 0.41 LCMS-1 11-Sep-06 0.36 LCMS-1 0.16 LCMS-1 25-Sep-06 0.94 LCMS-1 0.58 LCMS-1 10-Oct-06 0.76 LCMS-1 0.41 LCMS-1 23-Oct-06 0.63 LCMS-1 0.43 LCMS-1 6-Nov-06 0.68 LCMS-1 0.43 LCMS-1 20-Nov-06 0.58 LCMS-1 0.47 LCMS-1 19-Dec-06 0.53 LCMS-1 0.42 LCMS-1 2-Jan-07 0.74 LCMS-1 0.62 LCMS-1 16-Jan-07 0.45 LCMS-1 0.34 LCMS-1 30-Jan-07 0.47 LCMS-2 0.40 LCMS-2 26-Feb-07 0.60 LCMS-2 0.27 LCMS-2 12-Mar-07 0.44 LCMS-2 0.30 LCMS-2 26-Mar-07 0.48 LCMS-2 0.11 LCMS-2 2-Apr-07 0.46 LCMS-2 0.12 LCMS-2 9-Apr-07 0.52 LCMS-2 0.27 LCMS-2 18-Apr-07 1.69 LCMS-2 0.93 LCMS-2 23-Apr-07 1.47 LCMS-2 0.93 LCMS-2 30-Apr-07 2.04 LCMS-2 1.27 LCMS-2 7-May-07 1.75 LCMS-2 1.05 LCMS-2 14-May-07 1.70 LCMS-2 0.20 LCMS-2 21-May-07 1.65 LCMS-2 0.88 LCMS-2 29-May-07 1.74 LCMS-2 1.26 LCMS-2 4-Jun-07 1.54 LCMS-2 0.83 LCMS-2 11-Jun-07 1.58 LCMS-2 0.80 LCMS-2 18-Jun-07 1.63 LCMS-2 1.00 LCMS-2 25-Jun-07 1.60 LCMS-2 1.12 LCMS-2

9-Jul-07 0.14 LCMS-2 0.03 LCMS-2* 16-Jul-07 0.15 LCMS-2 0.03 LCMS-2* 23-Jul-07 0.13 LCMS-2 0.08 LCMS-2 30-Jul-07 0.15 LCMS-2 0.12 LCMS-2 

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...13-Aug-07 0.12 LCMS-2 0.11 LCMS-2 27-Aug-07 0.13 LCMS-2 0.06 LCMS-2 10-Sep-07 0.15 LCMS-2 0.10 LCMS-2 24-Sep-07 0.15 LCMS-2 0.09 LCMS-2 16-Oct-07 0.16 LCMS-2 0.07 LCMS-2 22-Oct-07 0.14 LCMS-2 0.12 LCMS-2 5-Nov-07 0.12 LCMS-2 0.09 LCMS-2 19-Nov-07 0.19 LCMS-2 0.14 LCMS-2 3-Dec-07 0.14 LCMS-2 0.12 LCMS-2 2-Jan-08 0.11 LCMS-2 0.11 LCMS-2 14-Jan-08 0.17 LCMS-2 0.15 LCMS-2 28-Jan-08 0.11 LCMS-2 0.09 LCMS-2 11-Feb-08 0.10 LCMS-2 0.09 LCMS-2 26-Feb-08 0.06 LCMS-2 0.03 LCMS-2* 10-Mar-08 0.06 LCMS-2 0.06 LCMS-2 24-Mar-08 0.07 LCMS-2 0.03 LCMS-2* 7-Apr-08 0.06 LCMS-2 0.03 LCMS-2* 14-Apr-08 0.03 LCMS-2* 0.03 LCMS-2* 21-Apr-08 0.03 LCMS-2* 0.03 LCMS-2* 28-Apr-08 0.03 LCMS-2* 0.03 LCMS-2* 5-May-08 0.06 LCMS-2 0.03 LCMS-2* 12-May-08 0.08 LCMS-2 0.06 LCMS-2 19-May-08 0.03 LCMS-2* 0.03 LCMS-2* 27-May-08 0.06 LCMS-2 0.07 LCMS-2 2-Jun-08 0.06 LCMS-2

- a - 2-Jun-08 0.07 LCMS-2

- a - 9-Jun-08 0.08 LCMS-2 0.07 LCMS-2 16-Jun-08 0.06 LCMS-2 0.03 LCMS-2* 24-Jun-08 0.03 LCMS-2* 0.03 LCMS-2* 30-Jun-08 0.07 LCMS-2 0.03 LCMS-2*

7-Jul-08 0.07 LCMS-2 0.03 LCMS-2* 14-Jul-08 0.06 LCMS-2 0.06 LCMS-2 21-Jul-08 0.07 LCMS-2 0.06 LCMS-2 28-Jul-08 0.06 LCMS-2 0.03 LCMS-2* 11-Aug-08 0.06 LCMS-2 0.03 LCMS-2* 25-Aug-08 0.06 LCMS-2 0.03 LCMS-2* 8-Sep-08 0.03 LCMS-2* 0.03 LCMS-2* 22-Sep-08 0.03 LCMS-2* 0.03 LCMS-2* 6-Oct-08 0.03 LCMS-2* 0.03 LCMS-2* 20-Oct-08 0.03 LCMS-2* 0.03 LCMS-2* 3-Nov-08 0.03 LCMS-2* 0.03 LCMS-2* 17-Nov-08 0.03 LCMS-2* 0.03 LCMS-2* 1-Dec-08 0.03 LCMS-2* 0.03 LCMS-2* 15-Dec-08 0.03 LCMS-2* 0.03 LCMS-2* 29-Dec-08 0.03 LCMS-2* 0.03 LCMS-2* 12-Jan-09 0.03 LCMS-2* 0.03 LCMS-2* 26-Jan-09 0.03 LCMS-2* 0.03 LCMS-2* 10-Feb-09 0.03 LCMS-2* 0.06 LCMS-2 23-Feb-09 0.03 LCMS-2* 0.03 LCMS-2* 9-Mar-09 0.03 LCMS-2* 0.03 LCMS-2* 23-Mar-09 0.03 LCMS-2* 0.03 LCMS-2* 6-Apr-09 0.03 LCMS-2* 0.03 LCMS-2* 13-Apr-09 0.03 LCMS-2* 0.03 LCMS-2* 20-Apr-09 0.03 LCMS-2* 0.03 LCMS-2* 27-Apr-09 0.03 LCMS-2* 0.03 LCMS-2* 4-May-09 0.03 LCMS-2* 0.03 LCMS-2* 

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...11-May-09 0.03 LCMS-2* 0.03 LCMS-2* 18-May-09 0.16 LCMS-2 0.12 LCMS-2 26-May-09 0.18 LCMS-2 0.15 LCMS-2

1-Jun-09 0.18 LCMS-2 0.15 LCMS-2 8-Jun-09 0.23 LCMS-2 0.16 LCMS-2 15-Jun-09 1.37 LCMS-2 0.81 LCMS-2 22-Jun-09 3.04 LCMS-2 2.77 LCMS-2 29-Jun-09 2.46 LCMS-2 1.84 LCMS-2

6-Jul-09 2.79 LCMS-2 2.14 LCMS-2 13-Jul-09 2.62 LCMS-2 1.95 LCMS-2 20-Jul-09 2.74 LCMS-2 1.73 LCMS-2 27-Jul-09 2.40 LCMS-2 2.00 LCMS-2 10-Aug-09 1.18 LCMS-2 1.10 LCMS-2 24-Aug-09 2.43 LCMS-2 2.04 LCMS-2 8-Sep-09 2.53 LCMS-2 1.75 LCMS-2 21-Sep-09 2.05 LCMS-2 1.64 LCMS-2 5-Oct-09 1.97 LCMS-2 1.70 LCMS-2 20-Oct-09 1.36 LCMS-2 1.22 LCMS-2 2-Nov-09 1.00 LCMS-2 1.04 LCMS-2 23-Nov-09 0.92 LCMS-2 0.77 LCMS-2 30-Nov-09 0.90 LCMS-2 0.76 LCMS-2 14-Dec-09 0.93 LCMS-2 0.65 LCMS-2 29-Dec-09 0.77 LCMS-2 0.67 LCMS-2 11-Jan-10 0.80 LCMS-2 0.70 LCMS-2 9-Feb-10 0.56 LCMS-2 0.55 LCMS-2 22-Feb-10 0.37 LCMS-2 0.46 LCMS-2 8-Mar-10 0.41 LCMS-2 0.42 LCMS-2 22-Mar-10 0.49 LCMS-2 0.39 LCMS-2 7-Apr-10 0.28 LCMS-3 0.26 LCMS-3 10-Apr-10 0.27 LCMS-3 0.28 LCMS-3 28-Apr-10 29.72 LCMS-3 23.57 LCMS-3 3-May-10 28.88 LCMS-3 26.81 LCMS-3 10-May-10 30.99 LCMS-3 29.57 LCMS-3 17-May-10 30.67 LCMS-3 29.57 LCMS-3 24-May-10 23.10 LCMS-3 27.44 LCMS-3

1-Jun-10 0.13 LCMS-3 0.67 LCMS-3 Avg. of Qtrly Means 1.67 1.46

*Indicates a non-detection or residue below the method's Limit of Quantitation (LOQ). For purposes of charting and calculation, 1/2 the method LOQ was used. The Immunoassay (IA) atrazine LOQ was 0.10 ppb. The Gas Chromatographic/Mass Selective Detection method (GC/MS) LOQ was 0.1 ppb.The Liquid Chroma tography / Mass Spectrometry / Mass Spectrometry (LC/MS) LOQ was typically 0.05-0.10 ppb. Montior Programs : Atrazine Monito ring Program Source type : Surface Water Ground Water Blended Water Not Available

a Sample result unavailable The time-weighted (TW) period mean is an average of quarterly averages.

Printed: 6/28/2010 

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