| Title: | Field test of electrokinetically-delivered thermally activated persulfate for remediation of chlorinated solvents in clay |
| Author(s): | Head NA; Gerhard JI; Inglis AM; Nunez Garcia A; Chowdhury AIA; Reynolds DA; de Boer CV; Sidebottom A; Austrins LM; Eimers J; O'Carroll DM; |
| Address: | "Department of Civil and Environmental Engineering, University of Western Ontario, 1151 Richmond Rd., London, Ontario, N6A 5B8, Canada. Institute of Water and Flood Management, Bangladesh University of Engineering and Technology, Dhaka, Bangladesh. Geosyntec Consultants, 130 Stone Road W, Guelph, N1G 3Z2, ON, Canada. Netherlands Organization for Applied Research, TNO, Princetonlaan 6, 3584 CB, Utrecht, the Netherlands. Dow Chemical, Fort Saskatchewan, AB, Canada. Dow Chemical, Environmental Remediation and Compliance, Midland, MI, 48674, USA. Jacobs, 72 Victoria St S, Kitchener, N2G 4Y9, ON, Canada. School of Civil and Environmental Engineering, Water Research Centre, University of New South Wales, Sydney, NSW, 2052, Australia. Electronic address: d.ocarroll@unsw.edu.au" |
| DOI: | 10.1016/j.watres.2020.116061 |
| ISSN/ISBN: | 1879-2448 (Electronic) 0043-1354 (Linking) |
| Abstract: | "In situ chemical oxidation (ISCO) has demonstrated success in remediating soil and groundwater contaminated with chlorinated volatile organic compounds (CVOCs). However, its performance is often hindered in low-permeability or heterogeneous media due to an inability to effectively deliver the oxidants. This field-scale study investigated the novel approach of applying electrokinetics (EK) to enhance the delivery of persulfate in a low-permeability media and the ability of electrical resistance heating (ERH) to thermally activate the delivered persulfate. Results showed that 40% of the mass of total sulfur delivered was due to EK mechanisms, demonstrating that EK has the potential to enhance oxidant delivery. ERH may have activated some of the persulfate, but catalytic reactions with reduced forms of iron likely resulted in appreciable persulfate decomposition prior to ERH. Significant decreases (>80%) in the aqueous concentration of CVOCs was observed before and after ERH initiation, attributed to in situ transformation and physical processes (e.g., dilution). In situ transformation of CVOCs was assessed by compound-specific isotope analysis (CSIA) of 1,2-dichloroethane (1,2-DCA) samples collected after ERH application. Enrichment of (13)C was only measured in the well with appreciable persulfate breakthrough, confirming dechlorination of 1,2-DCA. Results from this field study demonstrate that EK and ERH can be used for persulfate delivery and activation for remediation of CVOCs in low-permeability media" |
| Keywords: | "Clay *Environmental Restoration and Remediation *Groundwater Oxidation-Reduction Soil *Soil Pollutants Solvents Sulfates Water Pollutants, Chemical/*analysis Chlorinated solvents Electrokinetics In situ chemical oxidation Low-permeability soil Persulfate;" |
| Notes: | "MedlineHead, Nicholas A Gerhard, Jason I Inglis, Ainsley M Nunez Garcia, Ariel Chowdhury, Ahmed I A Reynolds, David A de Boer, Cjestmir V Sidebottom, Audrey Austrins, Leanne M Eimers, Jake O'Carroll, Denis M eng England 2020/07/06 Water Res. 2020 Sep 15; 183:116061. doi: 10.1016/j.watres.2020.116061. Epub 2020 Jun 20" |
