Impacts of cross-regional mobility of construction and demolition waste in Australia

Abstract

There is a pressing global challenge to manage the massive generation of construction and demolition (C&D) waste, which amounts to over 10 billion tons per year and is part of the largest waste stream in the world. Inappropriate management of waste will generate a series of environmental, economic and social impacts. Recent reports suggest that multiple incentives cause C&D waste to be transported from the region where it was originally generated to other regions for further treatment. This cross-regional mobility will affect the amount of C&D waste being managed in the regions that export and import waste, thereby affecting the environmental, economic and social performance of the system. Previous studies adopted a local-closed theory to study C&D waste and there is little knowledge about cross-regional mobility of C&D waste and related impacts. To investigate these issues, this research was designed to understand the C&D waste treatment and management from a novel perspective addressing the impacts of the cross-regional mobility of the waste. This was done by: (1) investigating the management and cross-regional mobility of C&D waste in Australia; (2) evaluating the impacts of cross-regional mobility by using a novel methodology developed in this study; and (3) developing a series of recommendations for the management of C&D waste cross-regional mobility. Sufficient data was collected through a literature review, desktop surveys, site surveys, a series of expert interviews and a seminar, and professional databases to address all objectives. The study has generated many interesting results e.g., the reporting of in-depth knowledge of and the management status of C&D waste in Australia, including composition and generation, and fates1 and flows. Similarly, it quantified and mapped the C&D waste cross-regional mobility, including types of waste subjected to mobility, the routes of mobility, and associated regions. In terms of the impacts of C&D waste cross-regional mobility, the study demonstrates that if cross-regional mobility of C&D waste increases the recycling rate, this can reduce environmental impacts and increase industry income. With respect to the social aspect, if a considerable amount of C&D waste generated involved cross-regional mobility, employment opportunities for managing waste in regions that export waste will generally decrease. Based on the findings, ten optimisation strategies have been recommended for management of cross-regional mobility of C&D waste in Australia. This research is a first in Australia in considering cross-regional mobility of C&D waste management. The study offers an innovative research perspective by expanding the C&D waste management theory from the local-closed loop to a cross-regional network level. With respect to methodology, this study also improves management performance assessment methodologies for C&D waste by considering environmental, economic and social impacts of cross-regional mobility of waste. Novel assessment approaches, indicators, calculation methods and databases developed from the study will make a contribution to management performance assessment methodologies for C&D waste. In addition, the state-of-the-art information revealed in the study will enable local C&D waste management service providers to optimise their product category and investments.