On-site and in situ bioremediation of wood-preservative contaminated groundwater

This paper reviews ten years of research on on-site and in situ bioremediation of chlorophenol contaminated groundwater. Laboratory experiments on the development of a high-rate, fluidized-bed process resulted in a full-scale, pump-and-treat application which has operated for several years. The system operates at ambient groundwater temperature of 7 to 9°C at 2.7 d hydraulic retention time and chlorophenol removal efficiencies of 98.5 to 99.9%. The microbial ecology studies of the contaminated aquifer revealed a diverse chlorophenol-degrading community. In situ biodegradation of chlorophenols is controlled by oxygen availability, only. Laboratory and pilot-scale experiments showed the potential for in situ aquifer bioremediation with iron oxidation and precipitation as a potential problem.

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Pilot-Scale in Situ Bioremediation of Uranium in a Highly Contaminated Aquifer. 1. Conditioning of a Treatment Zone

Environmental Science & Technology ◽

10.1021/es051954y ◽

2006 ◽

Vol 40 (12) ◽

pp. 3978-3985 ◽

Cited By ~ 114

Author(s):

Wei-Min Wu ◽

Jack Carley ◽

Michael Fienen ◽

Tonia Mehlhorn ◽

Kenneth Lowe ◽

...

Keyword(s):

Pilot Scale ◽

In Situ Bioremediation ◽

Contaminated Aquifer ◽

Treatment Zone

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Fluidized-bed biofilms for chlorophenol mineralization

Water Science & Technology ◽

10.2166/wst.1995.0051 ◽

1995 ◽

Vol 31 (1) ◽

pp. 227-235 ◽

Cited By ~ 11

Author(s):

Jaakko A. Puhakka ◽

Esa S. Melin ◽

Kimmo T. Järvinen ◽

Päivi M. Koro ◽

Jukka A. Rintala ◽

...

Keyword(s):

Fluidized Bed ◽

Groundwater Remediation ◽

Research Effort ◽

Treatment Strategies ◽

Sole Source ◽

Pilot Scale ◽

High Rate ◽

Contaminated Groundwater ◽

Groundwater Temperature ◽

Loading Rates

This paper summarizes a five-year research effort on the development of a high-rate fluidized-bed biofilm system for remediation of chlorophenol contaminated groundwater. Laboratory-scale experiments with model compounds and actual contaminated groundwater included studies on aerobic and anoxic treatment, strategies for selective enrichment of chlorophenol degrading microorganisms, kinetics and stoichiometries of chlorophenol conversions, toxicity removal, growth and culture characterization, recovery from process upsets, and operation at suboptimal temperatures. The aerobic process using chlorophenols as the sole source of carbon and energy showed the greatest versatility and efficiency. The contaminated groundwater consisted of 2,3,4,6-tetrachlorophenol, 2,4,6-trichlorophenol and pentachlorophenol with total chlorophenol concentrations ranging from 45 to 55 mg/l. At room temperature, groundwater remediation resulted in over 99.9% mineralization at chlorophenol loading rates of 1000 mg/l/d and hydraulic retention times of less than 1h. At the groundwater temperature (7°C), similar removal efficiencies were obtained at chlorophenol loading rates of up to 740 mg/l/d. The laboratory results were successfully repeated in an on-site, pilot-scale demonstration.

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A bioengineering system for in situ bioremediation of contaminated groundwater

Journal of Industrial Microbiology & Biotechnology ◽

10.1038/sj.jim.2900321 ◽

1997 ◽

Vol 18 (2-3) ◽

pp. 189-197 ◽

Cited By ~ 13

Author(s):

R B Knapp ◽

B D Faison

Keyword(s):

Contaminated Groundwater ◽

In Situ Bioremediation

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Feasibility study of in-situ bioremediation for nitrobenzene-contaminated groundwater

Water Science & Technology Water Supply ◽

10.2166/ws.2017.014 ◽

2017 ◽

Vol 17 (4) ◽

pp. 1160-1167 ◽

Cited By ~ 2

Author(s):

Na Liu ◽

Yue Wang ◽

Yonglei An ◽

Feng Ding ◽

Xiaolong Yu ◽

...

Keyword(s):

Simulation Experiment ◽

Laboratory Simulation ◽

Contaminated Groundwater ◽

Site Conditions ◽

In Situ Bioremediation ◽

Degrading Bacterium ◽

Bacterium Strain ◽

Negative Factors ◽

Sufficient Oxygen

Although many studies have simulated in-situ bioremediation of contaminated groundwater, most of them have not considered hydrochemical conditions and indigenous microorganisms, thus potentially rendering results inapplicable to actual in-situ groundwater bioremediation projects. This study focused on a nitrobenzene-contaminated groundwater site located in Jilin City, China. The actual nitrobenzene-contaminated groundwater was taken from Jilin City to simulate in-situ groundwater bioremediation in the laboratory. The feasibility of in-situ bioremediation for nitrobenzene-contaminated groundwater was studied according to actual site conditions and characteristics of nitrobenzene-degrading microorganisms in groundwater. The results showed that nitrobenzene-degrading bacterium strain NB1 was the dominant species that could effectively and rapidly degrade nitrobenzene by a partial reductive pathway. No negative factors on the growth or degrading function of this strain in groundwater could be detected. During a laboratory simulation experiment, combined in-situ bioremediation technologies, namely air sparging and bioaugmentation, could readily remove approximately 89.56% of nitrobenzene from groundwater without adding nutrients; oxygen was found to be the important growth factor for strain NB1. As the substrate of nitroreductase, encoded by the nitrobenzene nitroreductase (nbzA) gene, nitrobenzene was likely to significantly affect the expression of this gene. In conclusion, in-situ bioremediation is a feasible way to solve the problem of nitrobenzene-contaminated groundwater in Jilin City as long as sufficient oxygen and biomass of strain NB1 is ensured.

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