Western Monmouth Utilities Authority (WMUA) treats wastewater utilizing anaerobic digestion, and the resulting sludge material is transferred to Phragmites australis reed beds, where the sludge is dewatered and excess nutrients are removed by the plants. The New Jersey Department of Environmental Protection (NJDEP) regulates the disposal of the reed bed material. Land application of sludge generated by wastewater treatment plants is also regulated by the United States Environmental Protection Agency. After a decade of sludge disposal, the WMUA reed beds now full to capacity. The material remaining in the beds needs to be disposed of so the beds can be reused. The presence of live Phragmites rhizomes does not allow this material to be used for land application.
WMUA commissioned CUES to explore the possibility of a treatment option that demoves/destroys the live Phragmites rhizomes. Researchers also evaluated the potential to destroy bacteria that might be present in WMUA sludge allowing the material to meet the highest possible USEPA/NJDEP designated class for land application. Researchers explored both physical and biological treatments. The physical treatment options tested allowing the material to heat via composting in order to kill both plant rhizomes and bacteria.