Emergy based carbon footprinting of household solid waste management scenarios in Pakistan

Waste management is a serious challenge across many resource constrained countries of the world leading to environmental issues such as pollution and high rates of soil occupation, health issues induced by poor hygienic conditions, and financial problems linked to the high costs associated to waste management, which have high impacts on municipal budget. In this study we determined the environmental impact of different waste disposal scenarios in a major city of Pakistan. Existing studies on the subject of waste management in Pakistan fail to account for the environmental burden of waste processing technologies. To counter this, in this paper we used Emergy based accounting procedures to obtain a donor or nature based perspective for environmental footprinting. Three scenarios were considered for the analysis consisting of the current practice of open dumping as Scenario A; sanitary landfilling with composting and material recycling as Scenario B and incineration with composting and recycling as Scenario C. Results were presented in the form of Emergy based input-output tables as well as greenhouse gas emissions as measured in kg CO2 equivalent (kCO2eq/t) per tonne of waste. Scenario A was the worst option due to its high emissions and lack of any useful output. Scenario B was identified as the best alternative as it resulted in similar amount of net emissions as Scenario C but with relatively lower stress on the environment as indicated by the Emergy indicators. In view of the subject city's resource constraints we recommend inducing waste reduction and minimization practices through public awareness campaigns. Resource contributions from the civic society are also suggested for erecting the necessary waste disposal infrastructure. The results and suggestions presented herein need to be highlighted in a timely manner in order to resolve environmental and public health risks posed by the current practices.