Pump-and-Treat Groundwater Remediation Using Chlorine/Ultraviolet Advanced Oxidation Processes

Groundwater Monitoring & RemediationVolume 35, Issue 2 p. 93-100 Cutting-Edge Technical Papers Pump-and-Treat Groundwater Remediation Using Chlorine/Ultraviolet Advanced Oxidation Processes by Andrew K. Boal, Andrew K. BoalSearch for more papers by this authorCurtis Rhodes, Curtis RhodesSearch for more papers by this authorSteve Garcia, Steve GarciaSearch for more papers by this author by Andrew K. Boal, Andrew K. BoalSearch for more papers by this authorCurtis Rhodes, Curtis RhodesSearch for more papers by this authorSteve Garcia, Steve GarciaSearch for more papers by this author First published: 29 January 2015 https://doi.org/10.1111/gwmr.12095Citations: 25Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Abstract Comparative studies of the use of chlorine/ultraviolet (Cl2/UV) and hydrogen peroxide/ultraviolet (H2O2/UV) Advanced oxidation processes (AOPs) to remove trichloroethylene (TCE) from groundwater in a pump-and-treat application were conducted for the first time at the full-scale operational level at two water treatment facilities in Northern California. In these studies, aqueous chlorine replaced hydrogen peroxide in the AOP treatment step, where the oxidant is exposed to UV light to produce highly reactive radical species that degrade groundwater contaminants. TCE removal rates as a function of initial chlorine dose and pH were then determined. At the site where the natural pH of the water was 7.1, TCE was removed (to a concentration of less than 0.5 µg/L) for nearly every chlorine dose point tested, and pH adjustment slightly enhanced the treatment process at this facility. The second site had a high natural pH of 7.7, and here, TCE was not completely removed for any chlorine dose up to 5.7 mg/L, although TCE removal did increase when the chlorine dose increased between 0.9 and 3.6 mg/L. Residual TCE remaining in the water post-Cl2/UV was readily removed using active carbon filtration, which is part of the overall treatment train at this facility. These studies also verified that Cl2/UV AOP did not interfere with the photolysis of N-nitrosodimethylamine or result in an effluent acutely toxic toward Ceriodaphnia dubia. Comparative economic analysis revealed that the chemical costs associated with Cl2/UV AOP were 25 to 50% of the costs associated with in place H2O2/UV AOP treatment. Citing Literature Supporting Information Filename Description gwmr12095-sup-0001-TableS1-S13.docxWord document, 39.5 KB Table S1. pH Changes of Water Treated with H2O2/UV AOP at the LFHC Facility Table S2. Characterization of Water Treated with H2O2/UV AOP at the HFLC Facility: Carbon Filter Effluent Table S3. pH Changes of Water Treated with H2O2/UV AOP at the HFLC Facility Table S4. Characterization of Water Treated with Cl2/UV AOP at the LFHC Facility with pH Adjustment Table S5. pH Changes of Water Treated with Cl2/UV AOP at the LFHC Facility: No pH Adjustment Table S6. pH Changes of Water Treated with Cl2/UV AOP at the LFHC Facility: With pH Adjustment Table S7. Characterization of Water Treated with Cl2/UV AOP at the LFHC Facility: Carbon Filter Effluent Table S8. pH Changes of Water Treated with Cl2/UV AOP at the HFLC Facility Table S9. Toxicity Date from the HFLC Facility Table S10. Flow Rates for H2O2/UV AOP tests at the LFHC and HFLC Facilities Table S11. Flow Rates for Cl2/UV AOP tests the LFHC and HFLC Facilities Table S12. Average RAYOX UV Photoreactor Operational Parameters at the LFHC Facility Table S13. Average RAYOX UV Photoreactor Operational Parameters at the HFLC Facility Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article. Volume35, Issue2Spring 2015Pages 93-100 RelatedInformation