Porewater chemistry and sulfide mineral characteristics were evaluated in a waste-rock pile at the Detour Lake gold mine, Ontario, Canada, that had weathered in situ for more than 30 years. Geochemical characterization suggests that the waste rock would be potentially acid generating. Porewater extracted from the waste rock ranged in pH from 7.05 to 8.35, suggesting on-going acid neutralization by carbonate-mineral dissolution. Of the trace elements, nickel occurs at the highest concentration in pyrrhotite (median of 2738 ppm in historical samples), the associated alteration rims, and in the porewater samples (median of 140 μg L⁻¹). Nickel:cobalt and nickel:iron ratios in the sulfide grains and alteration rims, together with the porewater data, suggest no preferential retention of nickel over cobalt, and that sorption sites were saturated. X-ray absorption near edge structure (XANES) spectroscopy measurements at the iron-, sulfur- and nickel-edges also indicate trace element associations within the sulfide grains and alteration rims, and the presence of oxidized species of iron and sulfur.

在加拿大安大略省的Detour Lake金矿的废石堆中对孔隙水的化学性质和硫化物的矿物特征进行了评估，该堆原位风化了30多年。地球化学特征表明，rock石可能会产生酸。从waste石中提取的孔隙水的pH值范围为7.05至8.35，这表明碳酸盐-矿物质溶解能持续进行酸中和。在微量元素中，镍在黄铁矿中的含量最高（历史样品中值为2738 ppm），相关的蚀变边缘以及在孔隙水样品中含量最高（中值为140μgL ^-1）。硫化物晶粒和蚀变边缘中镍：钴和镍：铁的比率以及孔隙水数据表明，镍没有比钴优先保留，吸附位点饱和。铁，硫和镍边缘的X射线吸收近边缘结构（XANES）光谱测量还表明，硫化物晶粒和蚀变边缘内的微量元素缔合，以及铁和硫的氧化物质的存在。