Organohalides are common environmental contaminants designated by the United States Environmental Protection Agency as priority pollutants due to their toxicity and prevalence in the environment. Cleaning up organohalide pollution is thus important for the protection of human health. Biochars (materials generated from high-temperature decomposition of organic matter) have unique surface properties that has led to interest in using them to clean up environmental contaminants. However, relatively little is known about the ability of biochar to stimulate the biological degradation of organohalides. In this project, researchers from three Universities will investigate how biochar can help enhance the cleanup of toxic organohalides in wastewater. The findings of the project will be tested and applied under real-world conditions through collaboration with wastewater treatment facilities. If successful, this research has the potential to create an inexpensive and effective treatment technology for the most important class of pollutants in the U.S.<br/><br/>This research will test the hypothesis that biochar can catalyze the microbial dehalogenation of emerging organohalides through accelerated extracellular electron transport. In this project, the team will: (1) quantify the biochar-catalyzed microbial degradation of organohalides and their degradation products by two pure cultures of known model bacteria; (2) study the effects of nano-sized biochar, lowest-valent biochar, and nano-sized lowest-valent biochar on biotic and abiotic dehalogenation; (3) analyze the degradation of organohalides by a natural microbial community in the presence of biochar and study this potential application for advanced wastewater treatment. This project will provide timely information for the biochar-catalyzed microbial degradation of emerging organohalides. Lowest-valent biochar and nano-sized lowest-valent biochar, as novel analogs to zero-valent iron and nano zero-valent iron, will be produced and studied for their role in the degradation of organohalides. The intellectual merit is derived from the novel understanding of the role biochar properties play in catalyzing the microbial reductive dehalogenation of organohalides. The project has the potential to create a cost-effective strategy for the treatment of organohalide-contaminated waters in the U.S. and other countries. By working with UNR's Dean's Future Scholars program and The North Star STEM Alliance program at the University of Minnesota - Twin Cities, the investigators will offer summer research internships for first-generation college-bound middle school students and underrepresented graduates in STEM fields to enhance awareness and knowledge of modern water quality problems and technological solutions. Research results will also be integrated into current undergraduate and graduate courses.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.