A zero emissions landfill: Turning myth to reality

Abstract

The ever increasing population has been the root cause for the outburst of solid wastes. Dumping wastes in a pit or an open area had been in practice ever since the advent of civilization. With the growing awareness about the health risks associated with the open dumping of the wastes, landfills gained eminence. Landfills have been modified from simple dumping to the engineered landfills with the liners. Initially, the major concern of a landfill was the pervasive odor which affected the lives of dwellers around the landfill area. As the gases such as methane (CH4) and carbon dioxide (CO2) got recognized as the major contributors of global climate change, the landfill emissions became more critical. Currently, landfills are considered to be the third largest source of CH4 emissions in the United States (US). Various efforts have been made to control the landfill emissions such as providing low permeability landfill covers, installing gas extraction systems, and the biocovers. Landfills used to be considered as a liability due to the emissions and the odor. However, with the gas collection and recovery systems installed, the landfills have been able to generate revenue as well as lower the carbon footprint by converting extracted gas to energy. Modern engineered landfills with the engineered covers and gas extraction systems are able to keep the emissions to the minimum level, however there are fugitive emissions emanating from the landfills and contributing to the global climate change. Recently, in an attempt to capture those fugitive emissions and render landfills emissions free, an alternative landfill cover called biogeochemical cover concept was introduced. The biogeochemical cover aims to remove CO2, hydrogen sulfide (H2S), and CH4. This paper discusses the progressive transformation of landfills into zero emissions landfills.