Rittmann Using an AOP to partially transform recalcitrant compounds into biodegradable products allows for a cost-effective and robust overall treatment scheme. Prior research into integrated systems has focused on sequentially coupled systems, or those that have the biological and chemical treatments in separate stages. However, because AOP reactions are rapid and indiscriminate, they produce a large range of products, including those that are too oxidized, toxic themselves, or unavailable for biodegradation. Thus, integration could be improved if a single- stage -- or intimately coupled -- treatment system could be employed. If the bacteria were in close proximity to advanced oxidation, biodegradable products could be removed from solution as they are produced, focusing the chemical oxidant only on the recalcitrant compounds. In the past, intimate coupling has seemed impossible, because the reactants used in advanced oxidation are severely toxic to bacteria. The proposed research will investigate a novel photo-bio system that can achieve the ideal of intimate coupling, a truly unique and untested concept within the emerging field of coupled chemical-biological treatment.