Successful Application of a High-Performance Ozone-Based Advanced Oxidation Process (AOP) for Remediation of Heavily Contaminated Groundwater

A high performance O3/H2O2 advanced oxidation process was tested for removing trace amounts of NDMA and 1,4-dioxane from samples of highly contaminated groundwater extracted from the Stringfellow Superfund Site. After undergoing a series of pretreatment processes to remove metals, pesticides and COCs, the influent water for the O3/H2O2 process showed a COD of nearly 1,000 mg/L and TOC over 200 mg/L. Bench testing of the O3/H2O2 process was conducted using a proprietary reactor design, that optimizes the AOP performance. The results indicated that an average and a maximum O3 doses of 350 mg/L and 550 mg/L, respectively (coupled in each case with an H2O2 dose of about half of that of O3) were able to meet the treatment goals. This O3/H2O2 system was tested as an alternative to Fenton Reagent, and demonstrated superior performance by consistently meeting the treatment goals. Consequently, this O3/H2O2 AOP replaced Fenton Reagent in the design of the new facility for remediation of this contaminated groundwater source.