Environmental Engineering Reference
In-Depth Information
PCE and cis-DCE Rate Constants Based on Total Mass
2.5
y = 0.8102x − 0.0844
R
2
= 0.8243
2
1.5
1
0.5
0
−
0.5
0
0.5
1
1.5
2
2.5
3
−
0.5
1.
−1
y =
−
0.5608x + 0.0766
R
2
= 0.8198
−
−
2
Time (years)
ln (PCE C/Co)
ln (cis-DCE C/Co)
Linear (ln (PCE C/Co))
Linear (ln (cis-DCE C/Co))
Figure 5.49
Rate constants for cis-DCE and PCE calculated using total mass estimated
from contour plots of data for individual sampling events.
occurring at the Sage's site in the dissolved phase is quite rapid; the dissolved
PCE plume could meet the regulatory limit of 5 μg/l within 10 to 15 years.
5.6 Conclusions on utility in remediation
The goal of the chlorinated solvents thrust area was to develop and demon-
strate biological remediation technologies for chlorinated solvents. This
project focused on one such technological approach for source area treat-
ment, a subarea for which current technologies are limited but which must
be addressed if viable, cost-effective approaches are to be implemented at
solvent-contaminated sites.
The SERB technology has several advantages for remediation of
free-phase DNAPLs in the subsurface. These include:
•
Rapid removal of large masses of DNAPL in a very short time
•
In situ
treatment train technique
•
Cosolvent injection/extraction overcomes transport and mixing lim-
itations of standard bioremediation infiltration and injection
techniques
•
DNAPL mass removal reduces toxicity to microbes for bioremedia-
tion
•
Continued removal of dissolved contaminants following cessation of
pumping
•
Combination of an active process, solvent extraction, with an essen-
tially passive process, residual biotreatment
