Field demonstration of biostimulation with wine pomace extract at a chloroethene contaminated site

Abstract

Chloroethenes, which are widely used in industrial cleaning solutions and degreasing agents, are carcinogenic and their improper disposal has resulted in the contamination of soil and groundwater. A pilot study was conducted in a field contaminated with trichloroethene to evaluate the effectiveness of wine pomace extract (WPE) as a hydrogen donor in the anaerobic bioremediation of chloroethenes. WPE was prepared by extracting organic acids and other substances from grape pomace generated during winemaking. When WPE was injected into the soil, a reducing environment was created, the concentration of chloroethenes was decreased, and the number of Dehalococcoides spp. was increased. Additionally, before the injection of WPE, microbiota in groundwater and soil was dominated by dechlorinating bacteria, but after the injection, the number of co-metabolizing microorganisms was increased. We found that WPE activates various bacteria involved in the degradation of chloroethenes and can be used in actual contaminated sites.