Dr. Xinwei Mao's research interests lie in her passion of advancing and applying the knowledge of environmental microbiology to establish cost-effective and energy efficient wastewater treatment processes and promote a sustainable relationship between humans and the natural water environment. Dr. Mao is in currently developing novel on-site wastewater treatment systems in collaboration with Stony Brook's Center for Clean Water Technology (CCWT). These systems are based on novel de-nitrification pathways to treat on-site wastewater that is both cost-effective and energy - efficient. Research is underway to test the feasibility of these novel on-site wastewater treatment systems at the micro level in the lab as well as the feasibility at the macro level through field testing. Other research interests include bio-remediation of recalcitrant contaminants in groundwater and sediments, as well as bio-energy production from waste and wastewater.