@article {726,
	title = {Biodegradation of ethylene dibromide (1,2-dibromoethane [EDB]) in microcosms simulating in situ and biostimulated conditions.},
	journal = {J Hazard Mater},
	volume = {209-210},
	year = {2012},
	month = {2012 Mar 30},
	pages = {92-8},
	abstract = {Although 1,2-dibromoethane (EDB) is a common groundwater contaminant, there is the lack of knowledge surrounding EDB biodegradation, especially under aerobic conditions. We have performed an extensive microcosm study to investigate the biodegradation of EDB under simulated in situ and biostimulated conditions. The materials for soil microcosms were collected from an EDB-contaminated aquifer at the Massachusetts Military Reservation in Cape Cod, MA. This EDB plume has persisted for nearly 40 years in both aerobic and anaerobic EDB zones of the aquifer. Microcosms were constructed under environmentally relevant conditions (field EDB and DO concentrations; incubated at 12{\textdegree}C). The results showed that natural attenuation occurred under anaerobic conditions but not under aerobic conditions, explaining why aerobic EDB contamination is so persistent. EDB degradation rates were greater under biostimulated conditions for both the aerobic and anaerobic microcosms. Particularly for aerobic biostimulation, methane-amended microcosms degraded EDB, on average, at a first order rate eight times faster than unamended microcosms. The best performing replicate achieved an EDB degradation rate of 7.0 yr(-1) (half-life (t(1/2))=0.10 yr). Residual methane concentrations and the emergence of methanotrophic bacteria, measured by culture independent bacterial analysis, provided strong indications that EDB degradation in aerobic methane-amended microcosms occurred via cometabolic degradation. These results indicate the potential for enhanced natural attenuation of EDB and that methane could be considered co-substrate for EDB bioremediation for the EDB-contaminated groundwater in aerobic zone.},
	keywords = {Aerobiosis, Anaerobiosis, Biodegradation, Environmental, Ethylene Dibromide, Water Microbiology, Water Pollutants, Chemical},
	issn = {1873-3336},
	doi = {10.1016/j.jhazmat.2011.12.067},
	author = {McKeever, Robert and Sheppard, Diane and N{\"u}sslein, Klaus and Baek, Kyung-Hwa and Rieber, Khalil and Ergas, Sarina J and Forbes, Rose and Hilyard, Mark and Park, Chul}
}
@article {728,
	title = {Performance of a pilot-scale packed bed reactor for perchlorate reduction using a sulfur oxidizing bacterial consortium.},
	journal = {Biotechnol Bioeng},
	volume = {109},
	year = {2012},
	month = {2012 Mar},
	pages = {637-46},
	abstract = {A novel sulfur-utilizing perchlorate reducing bacterial consortium successfully treated perchlorate (ClO$_{4}$$^{-}$) in prior batch and bench-scale packed bed reactor (PBR) studies. This study examined the scale up of this process for treatment of water from a ClO $_{4}$$^{-}$ and RDX contaminated aquifer in Cape Cod Massachusetts. A pilot-scale upflow PBR (\~{}250-L) was constructed with elemental sulfur and crushed oyster shell packing media. The reactor was inoculated with sulfur oxidizing ClO$_{4}$$^{-}$ reducing cultures enriched from a wastewater seed. Sodium sulfite provided a good method of dissolved oxygen removal in batch cultures, but was found to promote the growth of bacteria that carry out sulfur disproportionation and sulfate reduction, which inhibited ClO$_{4}$$^{-}$ reduction in the pilot system. After terminating sulfite addition, the PBR successfully removed 96\% of the influent ClO$_{4}$$^{-}$ in the groundwater at an empty bed contact time (EBCT) of 12 h (effluent ClO$_{4}$$^{-}$ of 4.2 {\textmu}g L(-1)). Simultaneous ClO$_{4}$$^{-}$ and NO$_{3}$$^{-}$ reduction was observed in the lower half of the reactor before reactions shifted to sulfur disproportionation and sulfate reduction. Analyses of water quality profiles were supported by molecular analysis, which showed distinct groupings of ClO$_{4}$$^{-}$ and NO$_{3}$$^{-}$ degrading organisms at the inlet of the PBR, while sulfur disproportionation was the primary biological process occurring in the top potion of the reactor.},
	keywords = {Bioreactors, Cluster Analysis, DNA, Bacterial, DNA, Ribosomal, Massachusetts, Microbial Consortia, Molecular Sequence Data, Oxidation-Reduction, Perchloric Acid, Phylogeny, RNA, Ribosomal, 16S, Sequence Analysis, DNA, Sulfites, Sulfur, Water Microbiology, Water Pollutants, Chemical, Water Purification},
	issn = {1097-0290},
	doi = {10.1002/bit.24354},
	author = {Boles, Amber R and Conneely, Teresa and McKeever, Robert and Nixon, Paul and N{\"u}sslein, Klaus R and Ergas, Sarina J}
}
@article {736,
	title = {Hydrogenotrophic denitrification and perchlorate reduction in ion exchange brines using membrane biofilm reactors.},
	journal = {Biotechnol Bioeng},
	volume = {104},
	year = {2009},
	month = {2009 Oct 15},
	pages = {483-91},
	abstract = {Halophilic (salt loving), hydrogenotrophic (H(2) oxidizing) denitrifying bacteria were investigated for treatment of nitrate (NO3-) and perchlorate (ClO4-) contaminated groundwater and ion exchange (IX) brines. Hydrogenotrophic denitrifying bacteria were enriched from a denitrifying wastewater seed under both halophilc and non-halophilc conditions. The cultures were inoculated into bench-scale membrane biofilm reactors (MBfRs) with an "outside in" configuration, with contaminated water supplied to the lumen of the membranes and H(2) supplied to the shell. Abiotic mass transfer tests showed that H(2) mass transfer coefficients were lower in brines than in tap water at highest Reynolds number, possibly due to increased transport of salts and decreased H(2) solubility at the membrane/liquid interface. An average NO3- removal efficiency of 93\% was observed for the MBfR operated in continuous flow mode with synthetic contaminated groundwater. Removal efficiencies of 30\% for NO3- and 42\% for ClO4- were observed for the MBfR operated with synthetic IX brine in batch operating mode with a reaction time of 53 h. Phylogenetic analysis focused on the active microbial community and revealed that halotolerant, NO3- -reducing bacteria of the bacterial classes Gamma-Proteobacteria and Sphingobacteria were the metabolically dominant members within the stabilized biofilm. This study shows that, despite decreased H(2) transfer under high salt conditions, hydrogenotrophic biological reduction may be successfully used for the treatment of NO3- and ClO- in a MBfR.},
	keywords = {Bacteroidetes, Biofilms, Cluster Analysis, DNA, Bacterial, DNA, Ribosomal, Gammaproteobacteria, Hydrogen, Ion Exchange, Membranes, Molecular Sequence Data, Nitrites, Oxidation-Reduction, Perchloric Acid, Phylogeny, RNA, Ribosomal, 16S, Sequence Analysis, DNA, Water Pollutants, Chemical, Water Purification},
	issn = {1097-0290},
	doi = {10.1002/bit.22414},
	author = {Sahu, Ashish K and Conneely, Teresa and N{\"u}sslein, Klaus and Ergas, Sarina J}
}
