ABSTRACT
ABSTRACT: The threat of climate change caused by the emission of anthropogenic carbon has encouraged the international community to develop agreements such as the United Nations Framework Convention on Climate Change and the Kyoto Protocol. Upon ratification of the Kyoto Protocol, Canada committed, through the 2008-2012 commitment period, to reducing its greenhouse gas (GHG) emissions to 570 MT eCO2, from 1990 levels of 610 MT eCO2. The solid waste sector in Canada generated 24 MT eCO2 in 2000, 23 MT eCO2 of which were produced by landfill gas (LFG). The transport of waste likely generated a further 740 kT eCO2 that are not accounted for in the waste sector by the National Greenhouse Gas Inventory. It is likely that waste transport emissions will increase as fewer landfills are sited and further source separation of wastes occurs. The benefits of source reduction, recycling, LFG capture for energy recovery, composting, anaerobic digestion and incineration are discussed. This paper presents an estimation of the GHG emissions from the solid waste sector using the waste disposal, recycling, and composting data from Ottawa, Canada for the year 1999, as well as the results of an audit of residential units performed the same year. This evaluation determined that, among the options examined, waste incineration, further source separ-ation of recyclables, and anaerobic digestion of organic wastes have the greatest benefits for reducing GHG emissions in the City of Ottawa’s waste sector. Challenges surrounding the installation of incineration facilities in Canada suggest that improved diversion of recyclable materials and anaer-obic digestion of organic materials are the optimal options for the City of Ottawa to pursue.
