A field study of a novel permeable-reactive-biobarrier to remediate chlorinated hydrocarbons contaminated groundwater

Cuicui Liu; Xiaohui Chen; Shui Wang; Yongming Luo; Wenchao Du; Ying Yin; Hongyan Guo

doi:10.1016/j.envpol.2024.124042

A field study of a novel permeable-reactive-biobarrier to remediate chlorinated hydrocarbons contaminated groundwater

Environ Pollut. 2024 Apr 26:351:124042. doi: 10.1016/j.envpol.2024.124042. Online ahead of print.

Authors

Cuicui Liu¹, Xiaohui Chen², Shui Wang³, Yongming Luo⁴, Wenchao Du⁵, Ying Yin⁶, Hongyan Guo⁷

Affiliations

¹ Jiangsu Province Engineering Research Center of Soil and Groundwater Pollution Prevention and Control, Jiangsu Provincial Key Laboratory of Environmental Engineering, Jiangsu Provincial Academy of Environmental Science, Nanjing, 210036, China; Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China; State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing, 210023, China. Electronic address: 1612323084@qq.com.
² School of Civil Engineering, University of Leeds, Leeds, LS2 9JT, UK. Electronic address: X.Chen@leeds.ac.uk.
³ Jiangsu Province Engineering Research Center of Soil and Groundwater Pollution Prevention and Control, Jiangsu Provincial Key Laboratory of Environmental Engineering, Jiangsu Provincial Academy of Environmental Science, Nanjing, 210036, China. Electronic address: 35621101@qq.com.
⁴ Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China. Electronic address: ymluo@issas.ac.cn.
⁵ School of the Environment, Nanjing Normal University, Nanjing, 210023, China. Electronic address: du@njnu.edu.cn.
⁶ State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing, 210023, China. Electronic address: yinying@nju.edu.cn.
⁷ State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing, 210023, China; Joint International Research Centre for Critical Zone Science-University of Leeds and Nanjing University, Nanjing University, Nanjing, 210023, China. Electronic address: hyguo@nju.edu.cn.

PMID: 38679128
DOI: 10.1016/j.envpol.2024.124042

Abstract

Chlorinated hydrocarbons (CHs) pose significant health risks due to their suspected carcinogenicity, necessitating urgent remediation efforts. While the combination of zero-valent iron (Fe⁰) and microbial action shows promise in mitigating CH contamination, field studies on this approach are scarce. We devised a novel three-layer permeable reactive barrier (PRB) material incorporating Fe⁰ and coconut shell biochar, effectively implemented at a typical CH-contaminated site. Field monitoring data revealed conducive conditions for reductive dechlorination of CHs, characterized by low oxygen levels and a relatively neutral pH in the groundwater. The engineered PRB material consistently released organic carbon and iron, fostering the proliferation of CH-dechlorinating bacteria. Over a 250-day operational period, the pilot-scale PRB demonstrated remarkable efficacy in CH removal, achieving removal efficiencies ranging from 21.9% to 99.6% for various CH compounds. Initially, CHs were predominantly eliminated through adsorption and iron-mediated reductive dechlorination. However, microbial reductive dechlorination emerged as the predominant mechanism for sustained and long-term CHs removal. These findings underscore the economic viability and effectiveness of our approach in treating CH-contaminated groundwater, offering promising prospects for broader application in environmental remediation efforts.

Keywords: Biodegradation; Chlorinated hydrocarbons; Groundwater remediation; Permeable reactive barrier; Reduction.