Appendix 3. Comparison of Temporal Changes in Recovery of Pesticides in

Groundwater Matrix Spikes and in Stream-Water Matrix Spikes

This appendix is a series of similar graphs, including boxplots, for each of the pesticides and 

pesticide degradates discussed in the report. The boxplot explanation from figure 1 in the main text is 

reproduced below for readers’convenience. The series of graphs begins on the following page. 

0

50

100

150

Recovery, in percent
0

50

100

150

200

Recovery, in percent

Acetochlor groundwater matrix spikes: n: 785 Median: 103.1 Mean: 103.6 Standard deviation: 13.1

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Acetochlor stream−water matrix spikes: n: 1613 Median: 112.6 Mean: 113.6 Standard deviation: 15.6

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

0 0 0 12 67 150 120 178 162 151 130 144 141 70 74 54 64 51 45

0 0 0 19 78 61 56 77 83 87 61 42 49 42 33 38 22 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−1. Comparison of temporal changes in the recovery of acetochlor in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Alachlor groundwater matrix spikes: n: 994 Median: 102.7 Mean: 102.3 Standard deviation: 13.5

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Alachlor stream−water matrix spikes: n: 1815 Median: 111.1 Mean: 112.1 Standard deviation: 15.2

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

14 50 92 37 68 153 120 188 166 151 132 144 141 70 74 54 65 51 45

0 76 86 65 78 62 56 77 83 87 61 42 49 42 33 38 22 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−2. Comparison of temporal changes in the recovery of alachlor in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Atrazine groundwater matrix spikes: n: 977 Median: 100 Mean: 100.4 Standard deviation: 17.8

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Atrazine stream−water matrix spikes: n: 1760 Median: 103.8 Mean: 105 Standard deviation: 19.3

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

14 50 89 37 65 147 115 179 156 147 128 140 137 69 75 54 63 51 44

0 74 86 64 78 63 56 74 77 78 61 42 49 43 34 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−3. Comparison of temporal changes in the recovery of atrazine in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Azinphos−methyl groundwater matrix spikes: n: 998 Median: 100 Mean: 104.5 Standard deviation: 51.4

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Azinphos−methyl stream−water matrix spikes: n: 1735 Median: 142.2 Mean: 150.1 Standard deviation: 58.3

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 49 88 37 68 111 89 185 165 151 132 142 141 71 75 54 65 51 45

0 76 86 65 78 62 56 77 83 87 61 42 49 43 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−4. Comparison of temporal changes in the recovery of azinphos−methyl in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Benfluralin groundwater matrix spikes: n: 999 Median: 77 Mean: 77.6 Standard deviation: 17.7

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Benfluralin stream−water matrix spikes: n: 1743 Median: 84.9 Mean: 85.8 Standard deviation: 15.8

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 186 166 151 132 144 141 71 75 54 65 51 45

0 76 86 65 78 63 56 77 83 87 61 42 49 43 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−5. Comparison of temporal changes in the recovery of benfluralin in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Butylate groundwater matrix spikes: n: 781 Median: 95.3 Mean: 96.7 Standard deviation: 12.7

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Butylate stream−water matrix spikes: n: 1474 Median: 100.2 Mean: 101.8 Standard deviation: 14.4

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 92 37 68 153 120 188 166 151 131 125 116 24 18 19 0 0 0

0 76 86 65 78 63 56 77 83 87 59 30 21 0 0 0 0 0 0

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−6. Comparison of temporal changes in the recovery of butylate in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Carbaryl groundwater matrix spikes: n: 990 Median: 120.9 Mean: 134.6 Standard deviation: 66.9

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Carbaryl stream−water matrix spikes: n: 1799 Median: 133.8 Mean: 146.2 Standard deviation: 67.7

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 91 37 68 153 117 187 160 146 132 143 139 71 74 54 65 51 45

0 76 85 65 77 63 50 77 83 87 61 41 49 43 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−7. Comparison of temporal changes in the recovery of carbaryl in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Carbofuran groundwater matrix spikes: n: 945 Median: 116.9 Mean: 128.4 Standard deviation: 55.3

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Carbofuran stream−water matrix spikes: n: 1748 Median: 127.3 Mean: 139.3 Standard deviation: 54.3

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 49 87 37 68 151 120 188 165 146 131 125 116 59 75 54 65 51 45

0 76 85 65 77 62 56 77 83 87 59 30 21 34 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−8. Comparison of temporal changes in the recovery of carbofuran in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Chlorpyrifos groundwater matrix spikes: n: 998 Median: 92.4 Mean: 91.8 Standard deviation: 15.2

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Chlorpyrifos stream−water matrix spikes: n: 1740 Median: 98.3 Mean: 97.9 Standard deviation: 14.8

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 186 166 151 132 142 140 71 75 54 65 51 45

0 76 86 65 78 63 56 77 83 87 61 41 49 43 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−9. Comparison of temporal changes in the recovery of chlorpyrifos in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Cyanazine groundwater matrix spikes: n: 948 Median: 103.1 Mean: 102.8 Standard deviation: 22.7

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Cyanazine stream−water matrix spikes: n: 1758 Median: 113 Mean: 112.3 Standard deviation: 25

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 89 37 67 153 120 188 166 151 131 125 116 59 75 54 65 51 45

0 76 86 65 78 63 56 77 83 87 59 30 21 34 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−10. Comparison of temporal changes in the recovery of cyanazine in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
200

Recovery, in percent

150

100

50

0

Dacthal groundwater matrix spikes: n: 999 Median: 103.2 Mean: 104.1 Standard deviation: 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

200

Recovery, in percent

150

100

50

0

Dacthal stream−water matrix spikes: n: 1799 Median: 105.5 Mean: 106.2 Standard deviation: 15

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

200

Recovery, in percent

150

100

50

0

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

200

Recovery, in percent

150

100

50

0

0 76 86 65 78 63 56 77 83 87 61 42 49 43 35 38 23 21 16

0 50 88 37 68 153 120 188 166 151 132 144 141 71 75 54 65 51 45

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−11. Comparison of temporal changes in the recovery of Dacthal in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

p,p−DDE groundwater matrix spikes: n: 781 Median: 68.6 Mean: 69.6 Standard deviation: 13

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

p,p−DDE stream−water matrix spikes: n: 1396 Median: 61.1 Mean: 61.1 Standard deviation: 12

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 111 90 186 166 151 131 125 116 24 18 19 0 0 0

0 76 86 65 78 63 56 77 83 87 59 30 21 0 0 0 0 0 0

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−12. Comparison of temporal changes in the recovery of p,p’−DDE in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Deethylatrazine groundwater matrix spikes: n: 971 Median: 46.2 Mean: 48.1 Standard deviation: 21.2

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Deethylatrazine stream−water matrix spikes: n: 1810 Median: 47.6 Mean: 50.6 Standard deviation: 22.8

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 92 37 68 153 120 187 161 150 132 144 141 70 75 54 64 51 45

0 74 84 64 77 63 56 74 78 75 60 42 48 43 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−13. Comparison of temporal changes in the recovery of deethylatrazine in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Desulfinylfipronil groundwater matrix spikes: n: 243 Median: 99.1 Mean: 101.5 Standard deviation: 20.3

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Desulfinylfipronil stream−water matrix spikes: n: 535 Median: 111.5 Mean: 112.9 Standard deviation: 23.4

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

0 0 0 0 0 0 0 0 0 0 1 33 140 71 75 54 65 51 45

0 0 0 0 0 0 0 0 0 0 0 18 49 43 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−14. Comparison of temporal changes in the recovery of desulfinylfipronil in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Desulfinylfipr_amide groundwater matrix spikes: n: 243 Median: 90.9 Mean: 93.4 Standard deviation: 32.7

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Desulfinylfipr_amide stream−water matrix spikes: n: 535 Median: 116.6 Mean: 119.3 Standard deviation: 42.8

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

0 0 0 0 0 0 0 0 0 0 1 33 140 71 75 54 65 51 45

0 0 0 0 0 0 0 0 0 0 0 18 49 43 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−15. Comparison of temporal changes in the recovery of desulfinylfipronil amide in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Diazinon groundwater matrix spikes: n: 998 Median: 95.2 Mean: 94.7 Standard deviation: 14.2

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Diazinon stream−water matrix spikes: n: 1808 Median: 100.2 Mean: 100.4 Standard deviation: 14.9

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 92 37 68 151 117 188 166 151 132 139 140 71 75 54 65 51 45

0 76 86 65 78 63 56 77 83 87 61 41 49 43 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−16. Comparison of temporal changes in the recovery of diazinon in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Dieldrin groundwater matrix spikes: n: 996 Median: 92.7 Mean: 94.6 Standard deviation: 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Dieldrin stream−water matrix spikes: n: 1742 Median: 97.4 Mean: 98.7 Standard deviation: 16.2

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 87 37 68 113 90 186 166 151 132 144 141 71 75 54 65 51 45

0 76 86 65 75 63 56 77 83 87 61 42 49 43 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−17. Comparison of temporal changes in the recovery of dieldrin in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

2,6−Diethylaniline groundwater matrix spikes: n: 999 Median: 91.8 Mean: 92 Standard deviation: 16.7

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

2,6−Diethylaniline stream−water matrix spikes: n: 1743 Median: 90.4 Mean: 89.7 Standard deviation: 15.5

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 186 166 151 132 144 141 71 75 54 65 51 45

0 76 86 65 78 63 56 77 83 87 61 42 49 43 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−18. Comparison of temporal changes in the recovery of 2,6−diethylaniline in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Disulfoton groundwater matrix spikes: n: 948 Median: 72 Mean: 73.2 Standard deviation: 32.5

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Disulfoton stream−water matrix spikes: n: 1682 Median: 66.9 Mean: 66.8 Standard deviation: 28.2

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 186 165 151 130 123 116 59 75 54 65 51 45

0 76 86 65 78 63 56 77 83 87 59 30 21 34 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−19. Comparison of temporal changes in the recovery of disulfoton in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

EPTC groundwater matrix spikes: n: 948 Median: 93.7 Mean: 93.6 Standard deviation: 10.6

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

EPTC stream−water matrix spikes: n: 1681 Median: 94.6 Mean: 94.9 Standard deviation: 12.5

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 87 37 68 111 90 185 165 151 131 125 116 59 75 54 65 51 45

0 76 86 65 78 63 56 77 83 87 59 30 21 34 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−20. Comparison of temporal changes in the recovery of EPTC in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Ethalfluralin groundwater matrix spikes: n: 781 Median: 87.5 Mean: 89.4 Standard deviation: 22.7

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Ethalfluralin stream−water matrix spikes: n: 1398 Median: 97.1 Mean: 99.1 Standard deviation: 19.8

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 186 166 151 131 125 116 24 18 19 0 0 0

0 76 86 65 78 63 56 77 83 87 59 30 21 0 0 0 0 0 0

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−21. Comparison of temporal changes in the recovery of ethalfluralin in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Ethoprophos groundwater matrix spikes: n: 948 Median: 94.9 Mean: 96.3 Standard deviation: 17.4

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Ethoprophos stream−water matrix spikes: n: 1683 Median: 103.8 Mean: 106.7 Standard deviation: 20.1

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 186 166 151 131 123 116 59 74 54 65 51 45

0 76 86 65 78 63 56 77 83 87 59 30 21 34 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−22. Comparison of temporal changes in the recovery of ethoprophos in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Fipronil groundwater matrix spikes: n: 243 Median: 102.7 Mean: 104.7 Standard deviation: 28.7

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Fipronil stream−water matrix spikes: n: 535 Median: 134.6 Mean: 142 Standard deviation: 39.8

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

0 0 0 0 0 0 0 0 0 0 1 33 140 71 75 54 65 51 45

0 0 0 0 0 0 0 0 0 0 0 18 49 43 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−23. Comparison of temporal changes in the recovery of fipronil in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Fipronil_sulfide groundwater matrix spikes: n: 243 Median: 100 Mean: 101 Standard deviation: 22.5

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Fipronil_sulfide stream−water matrix spikes: n: 535 Median: 117.8 Mean: 119.7 Standard deviation: 24.6

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

0 0 0 0 0 0 0 0 0 0 1 33 140 71 75 54 65 51 45

0 0 0 0 0 0 0 0 0 0 0 18 49 43 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−24. Comparison of temporal changes in the recovery of fipronil sulfide in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Fipronil_sulfone groundwater matrix spikes: n: 243 Median: 83.9 Mean: 88.3 Standard deviation: 23.2

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Fipronil_sulfone stream−water matrix spikes: n: 535 Median: 101.3 Mean: 105.4 Standard deviation: 24.9

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

0 0 0 0 0 0 0 0 0 0 1 33 140 71 75 54 65 51 45

0 0 0 0 0 0 0 0 0 0 0 18 49 43 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−25. Comparison of temporal changes in the recovery of fipronil sulfone in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Fonofos groundwater matrix spikes: n: 997 Median: 90.6 Mean: 90.5 Standard deviation: 16.2

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Fonofos stream−water matrix spikes: n: 1741 Median: 96.4 Mean: 95.7 Standard deviation: 16.2

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 186 166 151 132 142 141 71 75 54 65 51 45

0 76 86 65 76 63 56 77 83 87 61 42 49 43 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−26. Comparison of temporal changes in the recovery of fonofos in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

alpha−HCH groundwater matrix spikes: n: 781 Median: 94.2 Mean: 94 Standard deviation: 14

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

alpha−HCH stream−water matrix spikes: n: 1397 Median: 96.2 Mean: 97 Standard deviation: 13.3

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 89 186 166 151 131 125 116 24 18 19 0 0 0

0 76 86 65 78 63 56 77 83 87 59 30 21 0 0 0 0 0 0

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−27. Comparison of temporal changes in the recovery of alpha−HCH in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

gamma−HCH groundwater matrix spikes: n: 778 Median: 96.3 Mean: 96.3 Standard deviation: 15.3

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

gamma−HCH stream−water matrix spikes: n: 1396 Median: 99.6 Mean: 100.2 Standard deviation: 15

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 184 166 151 131 125 116 24 18 19 0 0 0

0 76 86 65 75 63 56 77 83 87 59 30 21 0 0 0 0 0 0

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−28. Comparison of temporal changes in the recovery of gamma−HCH in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Linuron groundwater matrix spikes: n: 778 Median: 106.1 Mean: 111.6 Standard deviation: 42.4

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Linuron stream−water matrix spikes: n: 1393 Median: 113.9 Mean: 117.5 Standard deviation: 41.4

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 84 37 68 113 90 186 166 150 131 125 116 24 18 19 0 0 0

0 76 86 65 76 63 56 77 83 87 58 30 21 0 0 0 0 0 0

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−29. Comparison of temporal changes in the recovery of linuron in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Malathion groundwater matrix spikes: n: 999 Median: 95.8 Mean: 94.5 Standard deviation: 21.1

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Malathion stream−water matrix spikes: n: 1816 Median: 103.6 Mean: 103.6 Standard deviation: 24.7

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 92 37 68 153 120 188 166 151 132 141 141 71 75 54 65 51 45

0 76 86 65 78 63 56 77 83 87 61 42 49 43 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−30. Comparison of temporal changes in the recovery of malathion in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Metolachlor groundwater matrix spikes: n: 989 Median: 105.3 Mean: 105.8 Standard deviation: 14.3

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Metolachlor stream−water matrix spikes: n: 1787 Median: 110.7 Mean: 111.7 Standard deviation: 18

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

14 50 89 37 67 151 118 182 162 151 131 144 134 70 74 54 64 51 44

0 76 83 65 78 63 56 77 83 87 61 40 48 42 33 38 22 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−31. Comparison of temporal changes in the recovery of metolachlor in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Metribuzin groundwater matrix spikes: n: 999 Median: 85.8 Mean: 84.1 Standard deviation: 19.3

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Metribuzin stream−water matrix spikes: n: 1818 Median: 93.5 Mean: 93.1 Standard deviation: 19.7

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 92 37 68 153 120 188 165 151 132 144 141 71 75 54 65 51 45

0 76 86 65 78 63 56 77 83 87 61 42 49 43 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−32. Comparison of temporal changes in the recovery of metribuzin in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Molinate groundwater matrix spikes: n: 946 Median: 97.3 Mean: 97.6 Standard deviation: 11

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Molinate stream−water matrix spikes: n: 1685 Median: 100.4 Mean: 101.3 Standard deviation: 14.9

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 186 166 151 130 125 116 59 75 54 65 51 45

0 76 86 64 77 63 56 77 83 87 59 30 21 34 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−33. Comparison of temporal changes in the recovery of molinate in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Napropamide groundwater matrix spikes: n: 781 Median: 97.7 Mean: 99 Standard deviation: 14.9

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Napropamide stream−water matrix spikes: n: 1398 Median: 107.9 Mean: 109.1 Standard deviation: 17.2

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 186 166 151 131 125 116 24 18 19 0 0 0

0 76 86 65 78 63 56 77 83 87 59 30 21 0 0 0 0 0 0

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−34. Comparison of temporal changes in the recovery of napropamide in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Parathion groundwater matrix spikes: n: 781 Median: 96.2 Mean: 97.8 Standard deviation: 22.9

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Parathion stream−water matrix spikes: n: 1396 Median: 112 Mean: 114.7 Standard deviation: 24.6

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 186 166 151 131 123 116 24 18 19 0 0 0

0 76 86 65 78 63 56 77 83 87 59 30 21 0 0 0 0 0 0

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−35. Comparison of temporal changes in the recovery of parathion in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Parathion−methyl groundwater matrix spikes: n: 999 Median: 90.3 Mean: 93.2 Standard deviation: 25.5

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Parathion−methyl stream−water matrix spikes: n: 1739 Median: 108 Mean: 110.6 Standard deviation: 26.1

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 186 166 151 130 142 141 71 75 54 65 51 45

0 76 86 65 78 63 56 77 83 87 61 42 49 43 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−36. Comparison of temporal changes in the recovery of parathion−methyl in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Pebulate groundwater matrix spikes: n: 780 Median: 95.3 Mean: 95.6 Standard deviation: 17.3

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Pebulate stream−water matrix spikes: n: 1395 Median: 98.1 Mean: 98.9 Standard deviation: 12.5

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 186 166 151 130 124 116 23 18 19 0 0 0

0 76 86 64 78 63 56 77 83 87 59 30 21 0 0 0 0 0 0

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−37. Comparison of temporal changes in the recovery of pebulate in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Pendimethalin groundwater matrix spikes: n: 999 Median: 84.9 Mean: 86.2 Standard deviation: 24.3

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Pendimethalin stream−water matrix spikes: n: 1743 Median: 103.9 Mean: 105.3 Standard deviation: 24.5

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 186 166 151 132 144 141 71 75 54 65 51 45

0 76 86 65 78 63 56 77 83 87 61 42 49 43 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−38. Comparison of temporal changes in the recovery of pendimethalin in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

cis−Permethrin groundwater matrix spikes: n: 998 Median: 65.4 Mean: 77.7 Standard deviation: 49.2

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

cis−Permethrin stream−water matrix spikes: n: 1743 Median: 54.7 Mean: 58.7 Standard deviation: 30.2

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 186 166 151 132 144 141 71 75 54 65 51 45

0 75 86 65 78 63 56 77 83 87 61 42 49 43 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−39. Comparison of temporal changes in the recovery of cis−permethrin in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Phorate groundwater matrix spikes: n: 998 Median: 75.3 Mean: 73.2 Standard deviation: 20.6

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Phorate stream−water matrix spikes: n: 1740 Median: 75 Mean: 72.8 Standard deviation: 22.5

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 186 166 151 131 142 141 71 75 54 65 51 45

0 76 86 65 78 63 56 77 83 87 60 42 49 43 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−40. Comparison of temporal changes in the recovery of phorate in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Prometon groundwater matrix spikes: n: 995 Median: 95.4 Mean: 93.8 Standard deviation: 19.3

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Prometon stream−water matrix spikes: n: 1812 Median: 104 Mean: 103.6 Standard deviation: 19.1

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 153 120 188 166 151 132 144 140 71 75 54 64 51 44

0 76 85 64 78 63 56 77 83 87 61 41 49 43 34 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−41. Comparison of temporal changes in the recovery of prometon in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Propachlor groundwater matrix spikes: n: 779 Median: 104.7 Mean: 105.8 Standard deviation: 23.8

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Propachlor stream−water matrix spikes: n: 1396 Median: 116 Mean: 117.1 Standard deviation: 18.9

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 186 166 149 131 125 116 24 18 19 0 0 0

0 76 86 64 77 63 56 77 83 87 59 30 21 0 0 0 0 0 0

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−42. Comparison of temporal changes in the recovery of propachlor in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Propanil groundwater matrix spikes: n: 943 Median: 105.5 Mean: 105 Standard deviation: 18

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Propanil stream−water matrix spikes: n: 1686 Median: 117 Mean: 117.8 Standard deviation: 20.4

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 186 166 151 131 125 116 59 75 54 65 51 45

0 76 86 65 78 63 56 77 83 87 59 30 21 30 35 38 23 20 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−43. Comparison of temporal changes in the recovery of propanil in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Propargite groundwater matrix spikes: n: 937 Median: 91.3 Mean: 97.4 Standard deviation: 35.5

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Propargite stream−water matrix spikes: n: 1733 Median: 109.2 Mean: 113.2 Standard deviation: 39.1

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

15 49 88 37 68 153 120 177 161 150 131 121 114 59 75 54 65 51 45

0 76 86 65 78 63 53 69 83 87 59 30 21 34 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−44. Comparison of temporal changes in the recovery of propargite in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Propyzamide groundwater matrix spikes: n: 993 Median: 94.1 Mean: 93.4 Standard deviation: 15.6

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Propyzamide stream−water matrix spikes: n: 1741 Median: 103.6 Mean: 103.7 Standard deviation: 15.2

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 186 166 151 132 142 141 71 75 54 65 51 45

0 76 86 65 76 63 56 77 83 87 61 42 49 43 33 38 23 19 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−45. Comparison of temporal changes in the recovery of propyzamide in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Simazine groundwater matrix spikes: n: 999 Median: 96.3 Mean: 95.1 Standard deviation: 16.5

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Simazine stream−water matrix spikes: n: 1796 Median: 100.9 Mean: 100.5 Standard deviation: 19.3

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 153 120 187 162 151 131 144 132 71 75 53 63 51 44

0 76 86 65 78 63 56 77 83 87 61 42 49 43 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−46. Comparison of temporal changes in the recovery of simazine in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Tebuthiuron groundwater matrix spikes: n: 975 Median: 111.5 Mean: 112.6 Standard deviation: 31.6

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Tebuthiuron stream−water matrix spikes: n: 1732 Median: 122.9 Mean: 125.2 Standard deviation: 37

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 180 165 148 132 144 141 70 75 54 65 51 45

0 76 86 63 78 63 55 71 78 78 61 42 49 43 35 37 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−47. Comparison of temporal changes in the recovery of tebuthiuron in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Terbacil groundwater matrix spikes: n: 779 Median: 91.6 Mean: 98.5 Standard deviation: 47.8

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Terbacil stream−water matrix spikes: n: 1399 Median: 108.3 Mean: 113.7 Standard deviation: 47

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 186 166 150 131 125 116 24 19 19 1 0 0

0 76 84 65 78 63 56 77 83 87 59 30 21 0 0 0 0 0 0

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−48. Comparison of temporal changes in the recovery of terbacil in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Terbufos groundwater matrix spikes: n: 999 Median: 80.1 Mean: 80 Standard deviation: 20.8

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Terbufos stream−water matrix spikes: n: 1738 Median: 83.9 Mean: 84.9 Standard deviation: 20.9

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 186 166 151 131 140 141 71 75 54 65 51 45

0 76 86 65 78 63 56 77 83 87 61 42 49 43 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−49. Comparison of temporal changes in the recovery of terbufos in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Thiobencarb groundwater matrix spikes: n: 944 Median: 104.3 Mean: 103.8 Standard deviation: 14.8

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Thiobencarb stream−water matrix spikes: n: 1686 Median: 107 Mean: 108.2 Standard deviation: 15.4

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 186 166 151 131 125 116 59 75 54 65 51 45

0 76 86 65 78 63 56 77 83 87 59 30 21 30 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−50. Comparison of temporal changes in the recovery of thiobencarb in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Triallate groundwater matrix spikes: n: 781 Median: 93.9 Mean: 93.9 Standard deviation: 13.1

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Triallate stream−water matrix spikes: n: 1398 Median: 99 Mean: 99.1 Standard deviation: 13.2

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 186 166 151 131 125 116 24 18 19 0 0 0

0 76 86 65 78 63 56 77 83 87 59 30 21 0 0 0 0 0 0

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−51. Comparison of temporal changes in the recovery of triallate in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)
0

50

100

150

200

Recovery, in percent

Trifluralin groundwater matrix spikes: n: 999 Median: 79.6 Mean: 80.9 Standard deviation: 19

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

Trifluralin stream−water matrix spikes: n: 1743 Median: 89.9 Mean: 90.8 Standard deviation: 17.7

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

0

50

100

150

200

Recovery, in percent

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Comparison of lowess−modeled recovery

Groundwater matrix spikes

Stream−water matrix spikes

0

50

100

150

200

Recovery, in percent

16 50 88 37 68 113 90 186 166 151 132 144 141 71 75 54 65 51 45

0 76 86 65 78 63 56 77 83 87 61 42 49 43 35 38 23 21 16

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 3−52. Comparison of temporal changes in the recovery of trifluralin in groundwater matrix spikes and in

stream−water matrix spikes. In the bottom graph, boxplots for groundwater matrix spikes are plotted in the first half of the year,

and boxplots for stream−water matrix spikes are plotted in the second half of the year. The number of groundwater spikes is shown

at the top of the plot and the number of stream−water spikes is shown at the bottom of the plot. Boxplots are explained in figure 1.

(Recoveries greater than 200 percent are not shown.)