Third Indian Geotechnical Society: Ferroco Terzaghi Oration Design and Construction of Barrier Systems to Minimize Environmental Impacts Due to Municipal Solid Waste Leachate and Gas

Abstract

Based on case histories and the latest research, this paper examines municipal solid waste landfills as a system comprised of three primary subsystems (the hydrogeology and barrier system below the waste; the waste and landfill operations; and the landfill cover and landfill gas control system) that exists in a broader social/regulatory/administrative/economic system. Issues discussed include the effects of waste type and waste management risks, landfill leachate and leachate collection, landfill gas and gas collection, the hydrogeology and barrier subsystem required to contain contaminants in leachate and landfill gas from escape by both advection and diffusion, the dependence of a landfill design on the type and amount of waste and the operational model, materials specifications, and construction issues. Lessons to be learnt from the past problems are discussed together with the implications for modern waste management. The success of modern systems are noted together with the need to maintain vigilance and avoid complacency with respect to landfill siting, design, approval, construction, operations, after-use, and in approving subsequent surrounding land use. The importance of considering the interactions between the different components of the landfill system is discussed in the context of the need to ensure that changes in terms of waste stream or modes of landfill operations are carefully researched and considered in developing designs to provide long-term environmental protection.