The industrial solvent trichloroethylene (TCE) is among the most ubiquitous
chlorinated compounds found in groundwater contamination. The objective of
this study was to develop a barrier system, which includes a peat (used as
the primary substrates) layer to enhance the aerobic cometabolism of TCE i
n situ. A laboratory-scale column experiment was conducted to evaluate the
feasibility of using this peat biobarrier to remediate aquifers contaminate
d by TCE. This system was performed using a series of continuous-flow glass
columns including a soil column. a peat column, followed by two consecutiv
e soil columns. Activated sludges were inoculated in all three soil columns
to provide microbial consortia for TCE cometabolism. Simulated TCE contami
nated groundwater with a flow rate of 0.25 L/day was pumped into the system
. Effluent samples from each column were analyzed for TCE and its degradati
on byproducts [cis-dichloroethylene (cis-DCE) and vinyl chloride (VC)]. Ave
rage removal efficiency was 96% for TCE over a 60-day operating period. Acc
umulation of VC was observed due to the depletion of oxygen in the system.
Results from this laboratory study reveal that the developed biobarrier tre
atment scheme would be expected to provide a more cost-effective alternativ
e to remediate chlorinated-solvent contaminated aquifers.