Sustainability of Landfills in Urban Areas: Two Case Studies for Enhanced Utilization of Limited Land Area

Abstract

Sustainability of landfills is ensured by minimization of waste reaching landfill sites and eventual mining of stabilized waste from landfills (after several years) for re-use. Till such a scenario is achieved, expansion of landfill capacities is needed in urban areas. Non-availability of additional disposal sites within or near urban areas necessitates enhancement of capacities of landfills on existing limited land areas. This paper presents two case studies on enhancement of capacities of hazardous waste (HW) landfills where 35–50% more waste has been accommodated on the existing footprint of the landfills. The first case study pertains to design, construction and stability analysis of a new phase of HW landfill, which occupies the existing air space between two completed phases of the HW landfill. The special considerations for the integration of liner and cover components of the new phase with that of the corresponding components of the completed phases to attain complete containment have been highlighted. The second case study pertains to stability analyses conducted to increase utilization of air space on top of a landfill by increasing its height to more than double of its existing value. This study highlights that interface shear parameters between components of the cover and liner system govern the stability of the landfill slopes, and that use of textured geomembranes is desirable not only in the cover, but also in the basal lining systems.