A NONSTEADY-STATE ANALYTICAL MODEL TO PREDICT GASEOUS EMISSIONS OF VOLATILE ORGANIC-COMPOUNDS FROM LANDFILLS

A general mathematical model is developed to predict emissions of vola tile organic compounds (VOCs) from hazardous or sanitary landfills. Th e model is analytical in nature and includes important mechanisms occu rring in unsaturated subsurface landfill environments: biogas flow, le achate flow, diffusion, adsorption, degradation, volatilization, and m ass transfer limitations through the top cover. Two initial conditions simulating different environments are examined. The model is able to predict changes in subsurface concentrations and emission fluxes with time. The equations presented here can be extended to three dimensions to model VOC emissions from complex landfill sites.