Presented paper

IMWA2019 Students work

Responsible Mining Certification: Implications for mine characterization, monitoring, and modeling

Maest, Ann
Buka Environmental, United States of America

Several mine certification processes or responsible mining guidelines have been initiated over the last ten years to improve the environmental, social, corporate governance, and economic behavior of mines around the world. The best known efforts includes principles, guidelines, or requirements for mine water monitoring, and some include guidelines for geochemical and hydrologic characterization and modeling to predict water quality and water availability at mine sites during operations and closure.

To assure compliance with the requirements or guidelines, mine waste characterization, mine water monitoring, and water quality and quantity predictions must be carefully conducted and independently evaluated. The Mining Association of Canada has focused on tailings management, especially after the Mount Polley tailings spill disaster in 2014. ICMM holds 10 principles of sustainable development, including one related to continual improvement of environmental performance. IRMA’s Standard is the most specific in terms of mine waste characterization, monitoring, and predictions. While many of the principles and approaches are not new to countries such as the United States and Canada, abiding by the guidelines and requirements at mines in many locations around the world would represent and major improvement in transparency and social and environmental performance.

Because IRMA’s Standard is the most developed, the presentation will discuss elements of their program and how compliance with the requirements is evaluated. Characterization includes source characterization for acid drainage and metal leaching, a detailed description of geology, hydrogeology, hydrology, climate change predictions, and all potential sources of mining-impacted water. A conceptual model is required that describes the sources, pathways, and receptors, and water and chemistry mass balances for each facility. Baseline evaluations of water quantity and quality are required to take seasonality into account, and a scoping process includes collaboration with stakeholders to identify water-related concerns. If potential significant impacts are identified, numeric models are used to predict impacts on water quality and quantity, and the models must be continually revised based on new data and information. Stakeholders are also involved in evaluating mitigation measure options. Monitoring includes establishing trigger levels and an adaptive management plan. Evaluation of the characterization, monitoring, and modeling results will be discussed. The alignment of social and environmental responsibilities at mines is intended to improve performance and provide an opportunity for individual mines and companies to stake out an economic advantage in an era where consumers are more focused on responsible sourcing for all products, including electronics, cars, and building materials.