Experimental research on the transport-transformation of organic contaminants under the influence of multi-field coupling at a site scale

Fei Qiao; Jinguo Wang; Zhou Chen; Shiyu Zheng; Albert Kwame Kwaw; Yongsheng Zhao; Jintao Huang

doi:10.1016/j.jhazmat.2024.134222

Experimental research on the transport-transformation of organic contaminants under the influence of multi-field coupling at a site scale

J Hazard Mater. 2024 May 15:470:134222. doi: 10.1016/j.jhazmat.2024.134222. Epub 2024 Apr 4.

Authors

Fei Qiao¹, Jinguo Wang², Zhou Chen¹, Shiyu Zheng³, Albert Kwame Kwaw⁴, Yongsheng Zhao¹, Jintao Huang¹

Affiliations

¹ School of Earth Sciences and Engineering, Hohai University, Nanjing 210098 China.
² School of Earth Sciences and Engineering, Hohai University, Nanjing 210098 China. Electronic address: wang_jinguo@hhu.edu.cn.
³ School of Earth Sciences and Engineering, Hohai University, Nanjing 210098 China. Electronic address: njzsy123@hhu.edu.cn.
⁴ Department of Geological Engineering, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana.

PMID: 38583199
DOI: 10.1016/j.jhazmat.2024.134222

Abstract

Organic-contaminated shallow aquifers have become a global concern of groundwater contamination, yet little is known about the coupled effects of hydrodynamic-thermal-chemical-microbial (HTCM) multi-field on organic contaminant transport and transformation over a short time in aquifers. Therefore, this study proposed a quick and efficient field experimental method for the transport-transformation of contaminants under multi-field coupling to explore the relationship between organic contaminants (total petroleum hydrocarbon (TPH), polycyclic aromatic hydrocarbons (PAHs), benzene-toluene-ethylbenzene-xylene (BTEX) and phthalates acid esters (PAEs)) and multi-field factors. The results showed that hydrodynamics (affecting pH, p < 0.001) and temperature (affecting dissolved oxygen, pH and HCO₃^-, p < 0.05⁾ mainly affected the organic contaminants indirectly by influencing the hydrochemistry to regulate redox conditions in the aquifer. The main degradation reactions of the petroleum hydrocarbons (TPH, PAHs and BTEX) and PAEs in the aquifer were sulfate reduction and nitrate reduction, respectively. Furthermore, the organic contamination was directly influenced by microbial communities, whose spatial patterns were shaped by the combined effects of the spatial pattern of hydrochemistry (induced by the organic contamination pressure) and other multi-field factors. Overall, our findings imply that the spatiotemporal patterns of organic contaminants are synergistically regulated by HTCM, with distinct mechanisms for petroleum hydrocarbons and PAEs.

Keywords: Field experiment; Hydrodynamic-thermal-chemical-microbial monitoring; Organic-contaminated aquifer; Synergistic regulation.