Stability Analyses for Bioreactor Landfill Operations

摘要

This paper evaluates the performance of slope stability analyses as applied to landfills that are being operated with aggressive leachate/liquids recirculation or as a bioreactor. The re-introduction of liquids to a landfill mass has become more accepted by academicians, industry and regulators in recent years. The avoidance of the "dry tomb" landfill has many economic and environmental benefits including enhanced settlement and reuse of airspace, accelerated landfill gas production, more rapid stabilization and a possible reduction in post closure care requirements. The wet landfill-operating paradigm introduces some new concerns including slope stability. Traditional geotechnical methods of analyzing critical surfaces are typically applied. However, the input parameters and the range of values appropriate for wet landfills, including density, moisture content and friction angle may be different than for conventional landfill operations. It is also important to evaluate intermediate as well as final filled conditions. Seismic considerations are required for some locations. The paper will discuss recommended practices for performing slope stability analyses on wet landfills and will present a case history. Laboratory testing results for shear strength testing on wet, reacted wastes will be presented.