Natural-occurring microbial community in an organohalide polluted aquifer: preliminary evaluation of the effectiveness of permeable reactive bio-barriers for decontamination

Organohalides represent an issue for human health and are major contaminants around the world. At field scale along with chemical and physical treatments, often inefficient for organohalide degradation, biological approach based on bacterial anaerobic respiration can be applied. The aquifer under investigation is affected by multiple contaminations, i.e. organohalides, BTEX and petroleum hydrocarbons. In order to propose a bioremediation treatment, a preliminary evaluation was conducted on indigenous bacterial communities. Environmental genomic analyses revealed the presence of naturally-occurring organohalide-respiring and of vinyl chloride-oxidizing bacteria. Preliminary batch and pilot tests indicated that the installation of anaerobic permeable reactive bio-barriers could be effective in organohalide decontamination at the site.