Table 11 (cont'd). Analyte concentration (mg/kg) in the surface of test soils after
63, 112, or 173 days.
Moisture
status
1,3,5-TNB
1,3-DNB
2,4,6-TNT
1,2-DNB
2,4-DNT
2ADNT
4ADNT
c. Ft. Edwards clay
63 days
23C
Air-dried
Low moisture
0.228
0.239
1.51
High moisture
0.242
0.335
1.57
4C
Air-dried
Low moisture
0.736
0.631
High moisture
0.343
0.759
1.46
0.173
0.463
12C
Air-dried
0.161
Low moisture
High moisture
112 days
23C
Air-dried*
0.020
Low moisture
0.156
0.198
0.874
1.44
0.603
0.692
High moisture
0.176
0.205
1.18
1.49
0.675
0.688
4C
Air-dried*
Low moisture
0.065
0.761
0.215
1.05
High moisture
0.132
0.099
1.46
1.28
12C
Air-dried*
Low moisture*
High moisture*
* Values measured at 173 days; others measured at 112 days.
cate was sampled in a similar manner on day 112
measured for 2,4,6-TNT, 2,4-DNT, and 1,3-DNB
demonstrate that crystalline TNT was not present
for most combinations, again just after the vapor
in these samples, but rather that these analytes
sample was collected. For several of the air-dried
had migrated through the soil to the top few mil-
soil combinations, and some of the other combi-
nations at 12C, vapor analysis at 112 days indi-
limeters of surface soil.
In general, concentrations of TNT-related ana-
cated that target analytes were still below detec-
lytes were higher in soil samples held at 23C
tion limits; thus, in these cases, soil samples for
than in those held at 4C, and much higher than
the second replicate were delayed until day 173 to
concentrations in samples held at 12C. The con-
give additional time for target analytes to make
their way to the surface.
centrations of these analytes were often greater in
Results of the surface soil analysis for Ottawa
the soils with added moisture, relative to their
sand are presented in Table 11a. Measurable con-
air-dried counterparts, but this was not always
centrations of 2,4,6-TNT, 2,4-DNT, 1,3- and 1,2-
true for the Ottawa sand.
DNB, and 1,3,5-TNB were obtained for samples
Concentrations of TNT-related analytes in the
held at 23 and 4C. For samples held at 12C,
surface 5 mm in the silt soil ranged from less than
only 2,4-DNT, 1,3-DNB, and 2,4,6-TNT were de-
detection (about 0.02 mg/kg) to 3.1 mg/kg for
2,4,6-TNT in the high-moisture soil held at 23C
tected. Concentrations of the various TNT-related
analytes ranged from below a detection limit of
for 112 days (Table 11b). More of these analytes
about 0.02 mg/kg to 2.28 mg/kg for 2,4,6-TNT in
was always accumulated in the moist soils than
a high-moisture sample held at 23C for 112 days.
in the air-dried soils, and the greatest amounts
were in the soils held at 23C. Concentrations for
Generally, the analytes in the soil with the highest
soil samples held at 12C were very low, always
concentrations were either 2,4,6-TNT or 2,4-DNT
for samples held at 23 or 4C, but it was 1,3-DNB
at or below 0.2 mg/kg. The analytes present at
for samples held at 12C, confirming the higher
the highest concentrations were either 2,4,6-TNT
or 2,4-DNT in soil samples held at 23C, 2,4-DNT
mobility of this more volatile component at low
and 1,3-DNB in those held at 4C, and 1,3-DNB in
temperatures. The similarity in concentrations
19
To Contents
Previous Page
