Limits...
Natural attenuation model and biodegradation for 1,1,1-trichloroethane contaminant in shallow groundwater.

Lu Q, Zhu RL, Yang J, Li H, Liu YD, Lu SG, Luo QS, Lin KF - Front Microbiol (2015)

Bottom Line: The results indicated that the majority of the contaminant mass was present at 2-6 m in depth, the contaminated area was approximately 1000 m × 1000 m, and natural attenuation processes were occurring at the site.The effluent breakthrough curves from the column experiments demonstrated that the effectiveness of TCA natural attenuation in the groundwater accorded with the advection-dispersion-reaction equation.The contamination plume was predicted to diminish and the maximum concentration of TCA decreased to 280 μg/L.

View Article: PubMed Central - PubMed

Affiliation: State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resource and Environmental Engineering, East China University of Science and Technology , Shanghai, China.

ABSTRACT
Natural attenuation is an effective and feasible technology for controlling groundwater contamination. This study investigated the potential effectiveness and mechanisms of natural attenuation of 1,1,1-trichloroethane (TCA) contaminants in shallow groundwater in Shanghai by using a column simulation experiment, reactive transport model, and 16S rRNA gene clone library. The results indicated that the majority of the contaminant mass was present at 2-6 m in depth, the contaminated area was approximately 1000 m × 1000 m, and natural attenuation processes were occurring at the site. The effluent breakthrough curves from the column experiments demonstrated that the effectiveness of TCA natural attenuation in the groundwater accorded with the advection-dispersion-reaction equation. The kinetic parameter of adsorption and biotic dehydrochlorination of TCA was 0.068 m(3)/kg and 0.0045 d(-1). The contamination plume was predicted to diminish and the maximum concentration of TCA decreased to 280 μg/L. The bacterial community during TCA degradation in groundwater belonged to Trichococcus, Geobacteraceae, Geobacter, Mucilaginibacter, and Arthrobacter.

No MeSH data available.


Description of the contaminant plume of TCA in spatial and temporal [(A) Time 1 d, (B) Time 183 d, (C) Time 365 d, (D) Time 730 d, (E) Time 1825 d].
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4548683&req=5

Figure 4: Description of the contaminant plume of TCA in spatial and temporal [(A) Time 1 d, (B) Time 183 d, (C) Time 365 d, (D) Time 730 d, (E) Time 1825 d].

Mentions: A 3D reactive transport model with no persistent source was successfully developed and calibrated with the kTCA set to 0.0045 d–1. The location of the source area and the distribution of the contaminant plume based on field measurements in June 2007 were replicated in detail (Figure 4). In addition, the ongoing evolution of the plume was modeled for management and remediation project design. Under natural conditions, the modeled contaminant plume was fully representative of the time course of the plume in the aquifer. The source area (Figure 4, red section, C ≥ 25 mg/L) disappeared after about 1 year, due to the characteristics of the contaminated aquifer. After about 5 year, the area contaminated with TCA had diminished and the maximum concentration of TCA was 280 μg/L, below the DIV of 300 μg/L.


Natural attenuation model and biodegradation for 1,1,1-trichloroethane contaminant in shallow groundwater.

Lu Q, Zhu RL, Yang J, Li H, Liu YD, Lu SG, Luo QS, Lin KF - Front Microbiol (2015)

Description of the contaminant plume of TCA in spatial and temporal [(A) Time 1 d, (B) Time 183 d, (C) Time 365 d, (D) Time 730 d, (E) Time 1825 d].
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4548683&req=5

Figure 4: Description of the contaminant plume of TCA in spatial and temporal [(A) Time 1 d, (B) Time 183 d, (C) Time 365 d, (D) Time 730 d, (E) Time 1825 d].
Mentions: A 3D reactive transport model with no persistent source was successfully developed and calibrated with the kTCA set to 0.0045 d–1. The location of the source area and the distribution of the contaminant plume based on field measurements in June 2007 were replicated in detail (Figure 4). In addition, the ongoing evolution of the plume was modeled for management and remediation project design. Under natural conditions, the modeled contaminant plume was fully representative of the time course of the plume in the aquifer. The source area (Figure 4, red section, C ≥ 25 mg/L) disappeared after about 1 year, due to the characteristics of the contaminated aquifer. After about 5 year, the area contaminated with TCA had diminished and the maximum concentration of TCA was 280 μg/L, below the DIV of 300 μg/L.

Bottom Line: The results indicated that the majority of the contaminant mass was present at 2-6 m in depth, the contaminated area was approximately 1000 m × 1000 m, and natural attenuation processes were occurring at the site.The effluent breakthrough curves from the column experiments demonstrated that the effectiveness of TCA natural attenuation in the groundwater accorded with the advection-dispersion-reaction equation.The contamination plume was predicted to diminish and the maximum concentration of TCA decreased to 280 μg/L.

View Article: PubMed Central - PubMed

Affiliation: State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resource and Environmental Engineering, East China University of Science and Technology , Shanghai, China.

ABSTRACT
Natural attenuation is an effective and feasible technology for controlling groundwater contamination. This study investigated the potential effectiveness and mechanisms of natural attenuation of 1,1,1-trichloroethane (TCA) contaminants in shallow groundwater in Shanghai by using a column simulation experiment, reactive transport model, and 16S rRNA gene clone library. The results indicated that the majority of the contaminant mass was present at 2-6 m in depth, the contaminated area was approximately 1000 m × 1000 m, and natural attenuation processes were occurring at the site. The effluent breakthrough curves from the column experiments demonstrated that the effectiveness of TCA natural attenuation in the groundwater accorded with the advection-dispersion-reaction equation. The kinetic parameter of adsorption and biotic dehydrochlorination of TCA was 0.068 m(3)/kg and 0.0045 d(-1). The contamination plume was predicted to diminish and the maximum concentration of TCA decreased to 280 μg/L. The bacterial community during TCA degradation in groundwater belonged to Trichococcus, Geobacteraceae, Geobacter, Mucilaginibacter, and Arthrobacter.

No MeSH data available.