A closure cost estimate (CCE) is a detailed financial assessment of all expenditures anticipated to be incurred in the process of closing, decommissioning, and rehabilitating a mining operation, prepared to a defined level of engineering and cost estimating accuracy. Closure cost estimates are a fundamental requirement of mining permitting and regulatory compliance in virtually all jurisdictions where bauxite, gold, iron ore, and diamond mining takes place, and are used to determine the financial assurance (bond) required to be lodged by the mining company with regulatory authorities. A rigorous CCE encompasses the costs of infrastructure demolition and removal, earthworks for pit and waste dump stabilization, tailings storage facility (TSF) decommissioning and long-term management, soil remediation and revegetation, water treatment for post-closure seepage and drainage management, groundwater monitoring, social transition programs, and administrative and regulatory oversight. In bauxite mining, the long-term management cost of bauxite residue storage areas is a major component of the CCE. In gold mining, the cost of perpetual acid mine drainage (AMD) treatment can dominate the closure cost estimate. Closure cost estimates are typically prepared in accordance with established guidelines such as those issued by the International Council on Mining and Metals (ICMM), the Minerals Council of Australia, or national regulatory frameworks, and are classified according to cost estimate class systems such as the AACE International classification framework.
