Bioreactors are landfills where controlled addition of non-hazardous liquid wastes, sludges, or water accelerates the decomposition of waste and landfill gas generation. According to the Environmental Protection Agency, there are approximately 2,500 permitted municipal solid waste landfills (MSWLFs) currently in operation in the United States. Approximately 10% of these facilities will involve retrofitting bioreactors and commence leachate recirculation on existing landfill infrastructures. Current trends indicate that 10-15 new landfills are being constructed each year, with two to four facilities being constructed as bioreactors.
The bioreactor process enhances gas generation that can provide a revenue stream and decrease the contaminant load in the leachate. Both of these activities reduce the potential risks associated with the landfill while increasing its long-term stability. When evaluating the bioreactor landfill concept, three additional advantages can be identified:
This training, based on the ITRC's Characterization, Design, Construction, and Monitoring of Bioreactor Landfills (ALT-3, 2006), teaches the principles used to make critical decisions faced by regulatory agencies, consultants, and industry during permitting, operating, and monitoring a bioreactor landfill. This training also provides a general understanding of the biological degradation of solid wastes under aerobic and anaerobic waste conditions and the degradation products associated with each process.
- Decomposition and biological stabilization of the waste in a bioreactor landfill can occur in a much shorter time frame than occurs in a traditional "dry tomb" landfill
- Bioreactors reduced leachate handling costs
- Accelerated waste stabilization reduces the amount of post-closure care that may be necessary for the facility