Using the natural biodegradation potential of shallow soils for in-situ remediation of deep vadose zone and groundwater.
J Hazard Mater
; 324(Pt B): 398-405, 2017 Feb 15.
Article
en En
| MEDLINE
| ID: mdl-27836410
In this study, we examined the ability of top soil to degrade perchlorate from infiltrating polluted groundwater under unsaturated conditions. Column experiments designed to simulate typical remediation operation of daily wetting and draining cycles of contaminated water amended with an electron donor. Covering the infiltration area with bentonite ensured anaerobic conditions. The soil remained unsaturated, and redox potential dropped to less than -200mV. Perchlorate was reduced continuously from â¼1150mg/L at the inlet to â¼300mg/L at the outlet in daily cycles. Removal efficiency was between 60 and 84%. No signs of bioclogging were observed during three operation months although occasional iron reduction observed due to excess electron donor. Changes in perchlorate reducing bacteria numbers were inferred from an increased in pcrA gene abundances from â¼105 to 107 copied per gram at the end of the experiment indicating the growth of perchlorate-reducing bacteria. We proposed that the topsoil may serve as a bioreactor to treat high concentrations of perchlorate from the contaminated groundwater. The treated water that infiltrates from the topsoil through the vadose zone could be used to flush perchlorate from the deep vadose zone into the groundwater where it is retrieved again for treatment in the topsoil.
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Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Contaminantes Químicos del Agua
/
Percloratos
Idioma:
En
Revista:
J Hazard Mater
Asunto de la revista:
SAUDE AMBIENTAL
Año:
2017
Tipo del documento:
Article
País de afiliación:
Israel
Pais de publicación:
Países Bajos