Within mine closure planning, post-closure is the stage that follows the implementation of the Closure Plan, which includes monitoring and verification of emissions and effluents and, in general, the monitoring and control of all conditions resulting from the implementation of the measures and activities of the Closure Plan (Government of Chile 2012, Decree 41 that approves the Mine Closure Regulation of Mine Closure Law Chile). The post-closure stage has a fundamental role in proving that the physical and chemical stability of a mine site is maintained over time, as well as protecting the health and safety of people and the environment. In this way, post-closure seeks to identify deviations in these components in time, as well as the implementation of the necessary maintenance activities to avoid the degradation of the closure works.
Globally, the criteria for defining post-closure activities changes depending on the legislation of each country or region according to: the maturity of the environmental, mining and closure legislation; the way in which these legislations evolve; the economic development of the country or region, the available monitoring and maintenance technologies, among other factors.
The objective of this paper is to compare closure regulations of different jurisdictions that host medium and large-scale mining. The purpose of this comparison is to identify the similarities and differences with respect to post-closure monitoring and maintenance activities required by closure legislation, and to analyse the relative maturity level of post-closure practices at these jurisdictions.
In this way, the mining regulations associated with post-closure in Australia and South American countries (e.g., Bolivia, Brazil, Chile, Colombia, Ecuador and Peru) will be presented at first. Subsequently, different relative maturity levels will be defined with respect to post-closure activities according to post-closure aspects, such as existence of specific legislation for mine closure, and enforceability of the post-closure program and duration of the post-closure stage. Finally, a post-closure maturity level is assigned to each jurisdiction's legislation, based on the previously defined maturity levels.
