Chlorinated solvent contaminated soils and groundwater: field application of the solvent extraction residual biotreatment technology - Bioremediation of Recalcitrant Compounds - page 99

Pre-Ethanol Flush ~1 Month Post-Flush

C7 C7

C3 C3

C4 C4

MW-512

MW-512

MW-513 MW-514

MW-513 MW-514

C2

80000 ug/L

MW-505 C2

MW-505

C1 C1

70000 ug/L MW-506

MW-506

MW-509
MW-510
MW-511

MW-509
MW-510
MW-511 60000 ug/L

MW-507

MW-507

50000 ug/L

40000 ug/L

~2 Months Post-Flush ~3.5 Months Post-Flush

30000 ug/L

20000 ug/L

10000 ug/L

C7 C7

0 ug/L

C3 C3

C4 C4

MW-512 MW-512

MW-513 MW-514

MW-513 MW-514

C2 C2

MW-505 MW-505

C1 C1

MW-506 MW-506

MW-509
MW-510
MW-511

MW-509
MW-510
MW-511

MW-507 MW-507

Figure 5.15 PCE contour plots over the groundwater monitoring period (80,000 μg/
l = 480 μ M ).

~5.5 Months Post-Flush

~9.5 Months Post-Flush

C7

C7

C3

C4 C3

C4

MW-512 MW-512

MW-514 MW-513

MW-514 MW-513

C2 C2

80000 ug/L

MW-505 MW-505

C1

C1

70000 ug/L

MW-506

MW-506

MW-509
MW-510
MW-511

MW-509
MW-510
MW-511 60000 ug/L

MW-507 MW-507

50000 ug/L

40000 ug/L

~13.5 Months Post-Flush ~19 Months Post-Flush

30000 ug/L

20000 ug/L

10000 ug/L

C7 C7

0 ug/L C3 C3

C4 C4

MW-512 MW-512

MW-514 MW-513 MW-514 MW-513

C2 C2

MW-505 MW-505

C1 C1

MW-506 MW-506

MW-509
MW-510
MW-511

MW-509
MW-510
MW-511

MW-507 MW-507

Figure 5.16 PCE contour plots over the groundwater monitoring period (80,000 μg/
l = 480 μ M ).

next dechlorination product after DCE and is a known carcinogen and reg-
ulated contaminant. Interestingly, ethylene, which is the final dechlorination
product in the biotransformation of PCE, was detected at noticeable levels
within 6 months following the cosolvent flushing test (Figure 5.26). Ethylene
concentrations were somewhat variable, which may be due more to the
difficulty in sampling and analysis than to biological activity. The bar charts