# Prediction of Runoff-Evapotranspiration to Estimate Leachate Generation in a Landfill

by Reza M. Khanbilvardi, City Univ of New York, New York, United States,
Shabbir Ahmed, City Univ of New York, New York, United States,
Phillip J. Gleason, City Univ of New York, New York, United States,

Document Type: Proceeding Paper

Part of: Water Resources Planning and Management and Urban Water Resources

Abstract:

The fraction of precipitation that remains after runoff and surface water evaporation, enters into the solid waste landfill and generates leachate flow at the bottom. A part of the infiltration fraction of precipitation that enters and passes through the solid waste landfill is lost as soil evaporation and transpiration. The factors affecting the leachate generation rate such as runoff, surface water evaporation, soil water evaporation, and transpiration have been investigated for a landfill section. A mathematical model was formulated and subsequently applied to predict the runoff-evapotranspiration process in a landfill. It has been found that a high amount of surface runoff occurs due to the landfill side slope and as the moisture content of the landfill soil cover reaches toward saturation. The evapotranspiration process is dependent mainly on the climatological data and soil conditions of the landfill cover. The modified Penman method was used to predict the actual evapotranspiration that takes the effect of different climatological data and soil moisture conditions into account. The theory of the kinematic wave equation was used to model the surface runoff that takes the effect of landfill side slope and surface roughness into account. The theory related to the modified Penman method and the kinematic wave equation were successfully used to model the runoff-evapotranspiration process in a landfill.

Subject Headings: Landfills | Runoff | Soil water | Wave equations | Kinematic waves | Saturated soils | Mathematical models