Superfund Research Program

Oxidative Remediation of Superfund Contaminants

Project Leader: David L. Sedlak
Co-Investigator: Daniel K. Nomura
Grant Number: P42ES004705
Funding Period: 2006-2022

Project-Specific Links

Final Progress Reports

Year:   2016  2010 

The main goal of the research is to advance new, cost-effective ways of cleaning up groundwater and soil that has been contaminated by organic chemical from hazardous waste sites. One strategy for remediating contamination involves the introduction of chemical oxidants into groundwater wells. In the team’s previous research, they determined the mechanisms through which naturally occurring minerals react with the oxidants to initiate the contaminant degradation process. This year, the researchers studied the ways in which the oxidants degrade the contaminants. One of their major findings was that the oxidants unexpectedly caused aromatic compounds, like benzene and chlorophenol, to undergo ring cleavage reactions during the first step of oxidant attack. Some of the products of these reactions are known to be relatively toxic and need to be understood if this technique is to be applied widely. The second strategy for degrading contaminants employs electrochemical cells, with or without an ultraviolet lamp, to produce oxidants directly in the contaminated water. This year, the team focused their attention on the anode chamber of an electrochemical system that they had previously shown to be effective in producing hydrogen peroxide and reactive hydroxyl radicals. Using a suite of chemicals that each exhibited different reactivity with the oxidants suspected of being present, the researchers were able to ascertain the oxidants that were formed under different conditions. This allowed them to identify the kinds of contaminated waters that are most amendable to treatment and to anticipate the conditions under which unsafe levels of disinfection byproducts might be produced.