Table 7. Means and standard deviations of triplicate analyte values for experiment III performed
with vapor-fortified CR-B soil. For each analyte with the same method of sample preparation and
analysis, values with the same letter (or no letter at all) are not significantly different from each other.
Analyte concentration (g/g)
Method
Time
TDCE
CDCE
Ben
TCE
Tol
PCE
E-Ben
p-Xyl
o-Xyl
HS-NaHSO4
12 hr
0.68c
1.53a
1.40a
1.64a
2.54a
2.49a
2.56a
2.41b
2.36b
0.05
0.12
0.08
0.07
0.05
0.07
0.12
0.06
0.05
HS-NaCl/H3PO4
12 hr
0.45d
1.15b
0.99c
1.05c
1.61c
1.62c
1.58c
1.40d
1.37b
0.02
0.01
0.01
0.02
0.01
0.03
0.02
0.03
0.05
Heated HS
12 hr
1.28a
1.12b
1.04bc
1.34b
1.57c
1.95b
1.20d
1.09e
0.93e
0.02
0.08
0.02
0.03
0.01
0.03
0.01
0.02
0.01
<2 hr
MeOH
0.89b
1.47a
1.14b
1.52a
2.26b
2.29a
2.59a
2.76a
2.79a
0.02
0.00
0.01
0.05
0.08
0.10
0.10
0.14
0.07
<2 hr
Tetraglyme
0.50d
1.10b
0.76d
1.04c
1.45c
1.64c
1.81c
1.71c
1.63c
0.07
0.11
0.08
0.11
0.12
0.16
0.13
0.18
0.10
<2 hr
PPG
0.51d
0.99b
0.68d
0.91c
1.10d
1.34d
1.26d
1.20de
1.18d
0.09
0.19
0.14
0.18
0.25
0.30
0.22
0.33
0.24
MeOH
2 days
2.47
2.37
1.54
2.44
3.44
3.46
4.04
4.99
4.40
0.04
0.03
0.04
0.07
0.17
0.11
0.18
0.16
0.23
Tetraglyme
2 days
0.68
1.26
0.93
1.22
1.89
2.14
2.40
2.48
2.42
0.02
0.15
0.10
0.11
0.12
0.14
0.17
0.11
0.16
PPG
2 days
0.59
1.11
0.76
1.04
1.32
1.57
1.49
1.39
1.31
0.06
0.17
0.12
0.16
0.27
0.29
0.32
0.25
0.25
MeOH
4 days
2.83
2.68
1.58
2.52
3.52
3.04
3.85
4.97
4.30
0.04
0.03
0.07
0.09
0.11
0.17
0.35
0.40
0.37
Tetragylme
4 days
0.69
1.27
0.96
1.18
2.04
2.05
2.50
2.76
2.58
0.21
0.14
0.09
0.11
0.17
0.16
0.18
0.22
0.28
PPG
4 days
0.64
1.21
0.82
1.11
1.46
1.63
1.65
1.58
1.48
0.06
0.14
0.09
0.14
0.20
0.24
0.24
0.21
0.26
MeOH
29 days
4.09
3.77
2.16
4.03
4.80
4.44
5.04
6.66
5.54
0.08
0.06
0.05
0.17
0.07
0.02
0.07
0.19
0.17
Tetragylme
29 days
0.77
1.34
1.04
0.99
2.46
2.23
3.17
3.49
3.36
0.25
0.17
0.06
0.20
0.13
0.15
.015
0.20
0.25
PPG
29 days
0.77
1.26
0.85
1.25
1.55
1.79
1.78
1.80
1.59
0.07
0.14
0.13
0.18
0.29
0.30
0.36
0.41
0.21
* See Table 2 for full names.
determine which values were significantly differ-
sample preparation methods for vapor-fortified
ent.
samples. For this six-method comparison, samples
Figure 3 gives plots of the mean concentrations
were either prepared and analyzed within 2 hours
established for the three solvents for each extrac-
or a solvent aliquot was removed within 2 hours
tion period. In each figure, points designated with
of the ampoule contents being dispersed. This
a different letter are significantly different at the
table also shows the results for three additional
95% confidence level. With the exception of the 2-
solvent extraction periods. The CR-B soil was the
and 4-day extraction periods, which often showed
only matrix, and this was the only experiment that
no significant change, MeOH caused an increas-
included PPG as an extraction solvent. Two
ing concentration trend for all of the analytes. The
ANOVA tests were performed at the 95% confi-
slow rate of extraction for this soil with MeOH
dence level with this data set. One evaluated
was surprising since this trend was not observed
changes in analyte concentration relative to extrac-
in experiment II using the CR-A soil. Both the CR-
tion period for each of the three solvents, the other
A and CR-B soils were obtained the same general
compared the analyte concentrations established
area and at the same approximate depth. Although
among the six sample preparation methods. In
not reported here, the MeOH extraction kinetics
each case the Fisher's Protected LSD was used to
12
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