Use of Bioaugmentation for Continuous Removal of Carbon Tetrachloride in Model Aquifer Columns

Abstract

ABSTRACT The feasibility of sustained removal of carbon tetrachloride (CT) by Pseudomonas stutzeri KC was evaluated in two 2 meter-long columns packed with aquifer material from a CT-contaminated aquifer at Schoolcraft, MI. CT-contaminated groundwater was pumped continuously through both columns until the aqueous and adsorbed CT had equilibrated. CT transformation was initiated by inoculating an 8 cm-wide alkaline-adjusted zone near the upstream end of both columns with groundwater containing strain KC and acetate. CT-contaminated groundwater was then pumped continuously through the columns. Both columns received weekly acetate additions in the bioaugmentation zone. Base and phosphate additions were performed weekly in one column and twice weekly in the second column. A CT-transforming zone developed in the bioaugmentation zone of both columns, with 97% removal of CT in the column receiving weekly base additions and 93% removal in the column receiving twice-weekly base additions. Strain KC was detected on...