Geoenvironmental Considerations for Bulk Reuse of MSW Residues from Old Dumps and WTE Plants in Geotechnical Applications

For achieving sustainability in management of municipal solid waste (MSW), it is important to ensure that residues, remaining after processing of waste in various plants (composting, waste to energy (WTE), landfilling), are reutilised in a safe and useful manner. Such residues constitute more than 25–35% of the total MSW generated in urban areas. This paper examines the feasibility of using soil-sized residues from landfill mining operations as well as from WTE plants in large quantities (bulk) in geotechnical applications relating to earthworks and structural fills. The geotechnical properties of the residues as well as the contaminants of concern in these residues from two waste dumps and three waste-to-energy plants of Delhi have been evaluated and the critical parameters inhibiting their un-restricted bulk reuse have been identified. The role of high soluble solids, high organic content, elevated heavy metals, release of colour and variable pH has been brought out. The design measures and treatment methods that need to be adopted when using these residues in surface fills, shallow fills, deep fills and structural fills have been highlighted.