• – Bioreactor landfill;
  • channeled flow;
  • hydrodynamics;
  • leachate recirculation;
  • saturated–unsaturated flow and transport model (SUTRA)

Leachate recirculation is an emerging technology for theon-site management of leachate. The benefits of leachate recirculation have been well-documented by a variety of researchers. However, little work has been done to address the hydrodynamic behavior of the landfill, i.e. the effect of recirculation system and waste characteristics on leachate routing. A modified form of SUTRA – a United States Geological Survey (USGS) saturated–unsaturated flow and transport model – was used to simulate the forces driving liquid movement through a landfill. The variables evaluated included leachate input rates, the permeability of intermediate cover materials, waste permeability, and waste heterogeneity. The model was verified using data from operating landfills in Delaware, California, New York, and Florida.