Geochemical Characterization and Reactive Transport Simulation of Metal Leaching and Acid Generation in Waste Rock from the Ekati Diamond Mine, NT

采矿活动产生大量废料，可能对水和土壤质量以及接收废料的生态系统的健康产生不利影响。含硫化物的矿山废物，包括不经济的废石，风化可产生酸性排水，并促进无机成分，包括金属（类）和硫酸盐的释放。Ekati钻石矿位于西北地区耶洛奈夫东北约300公里处。Ekati将产生约820吨废石，其中包括鸽子露天矿的约50吨废石，主要由混合变沉积物和花岗岩-闪长岩组成。在现场条件下，该材料是不确定的产酸潜力;这一发现不同于实验室规模的湿度电池测试的结果进行了使用芯样收费，分类为潜在的产酸岩石。拟议的研究项目的范围是通过现场样品收集，实验室实验和表征以及反应运输建模的综合方案，重新评估鸽子坑废石的产酸和金属浸出潜力。拟议的项目将提供关键的见解，潜在的长期水质影响，可能会产生的废物岩石风化，并制定缩放关系，以预测污染物的释放，运输和衰减的领域;这些成果将被Ekati纳入封闭规划和封面设计。

Mining activities generate significant quantities of waste materials, which can negatively impact water and soil quality, and the health of receiving ecosystems. Weathering of sulfide-bearing mine wastes, including uneconomic waste rock, can generate acidic drainage and promote the release of inorganic constituents, including metal(loid)s and sulfate. The Ekati Diamond Mine is located approximately 300 km northeast of Yellowknife, NWT. Ekati will generate ~820 MT of waste rock, including ~50 MT of waste rock from the Pigeon Open Pit, which is comprised primarily of mixed metasediment and granite-diabase. Under field conditions, the material is of uncertain acid-generating potential; this finding differs from results of laboratory-scale humidity-cell tests conducted using core-sample charges, which classified the rock as potentially acid generating. The scope of the proposed research project is to re-assess the acid-generating and metal-leaching potential of waste rock from the Pigeon Pit through an integrated program of field-sample collection, laboratory experimentation and characterization, and reactive transport modelling. The proposed project will provide critical insights into the potential long-term water-quality impacts that may arise from waste-rock weathering, and develop scaling relationships to predict contaminant release, transport, and attenuation in the field; these outcomes will be integrated by Ekati into closure planning and cover design.