1 research outputs found
Microbial Community Dynamics during Acetate Biostimulation of RDX-Contaminated Groundwater
Biostimulation of
groundwater microbial communities (e.g., with
carbon sources) is a common approach to achieving in situ bioremediation
of organic pollutants (e.g., explosives). We monitored a field-scale
approach to remediate the explosive RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine)
in an aquifer near the Iowa Army Ammunition Plant in Middletown, IA.
The purpose of the study was to gain insight into the effect of biostimulation
on the microbial community. Biostimulation with acetate led to the
onset of RDX reduction at the site, which was most apparent in monitoring
well MW309. Based on previous laboratory experiments, we hypothesized
that RDX degradation and metabolite production would correspond to
enrichment of one or more FeÂ(III)-reducing bacterial species. Community
DNA from MW309 was analyzed with 454 pyrosequencing and terminal restriction
fragment length polymorphism. Production of RDX metabolites corresponded
to a microbial community shift from primarily FeÂ(III)-reducing Betaproteobacteria
to a community dominated by FeÂ(III)-reducing Deltaproteobacteria (Geobacteraceae
in particular) and Bacteroidetes taxa. This data provides a firsthand
field-scale microbial ecology context to in situ RDX bioremediation
using modern sequencing techniques that will inform future biostimulation
applications