Dep. Explotación y Prospección Minas, University of Oviedo, ETS Ingenieros de Minas, c/Independencia, 13, 33004, Oviedo, Asturias, Spain.
Environ Geochem Health. 2014 Apr;36(2):271-84. doi: 10.1007/s10653-013-9566-3. Epub 2013 Aug 29.
In Asturias (NW Spain) there are many abandoned mines, of which Hg mines are of particular significance from an environmental point of view, due to the presence of Hg and particularly As, which is found either in the form of specific (orpiment and realgar) or non-specific minerals (As-rich pyrite). The instability of these minerals leads to the presence of As-rich mine drainage and spoils heap leachates that enter surface waters or groundwaters. A study including the three most important Hg mines in the region (La Soterraña, Los Rueldos and El Terronal) has been conducted. Watercourses flowing through these mining areas are tributaries of the River Caudal, one of the most important rivers in the area. High concentrations of As were found in some of these waters, which were monitored over a period of three hydrological years and classified according to a water quality index. Those waters sampled close to the mines are generally of poor-to-bad quality, with low alkalinity and in some cases high metal content, but the quality of these waters improves with distance from the mines. The average mass load of As entering the River Caudal has been evaluated as: 200, 12 and 9,800 kg year(-1) from La Soterraña, Los Rueldos and El Terronal mine sites, respectively. Despite the constant input of about 10 tonnes of As per year, the total As concentration remains below analytical detection thresholds on account of the river's high water flow. Nevertheless, an important part of this As load is presumably retained in the river sediments, representing a potential risk of pollution of the aquatic ecosystems.
在西班牙阿斯图里亚斯（西北部）有许多废弃的矿山，其中汞矿从环境角度来看尤为重要，因为这些矿中存在汞，尤其是砷，砷以特定（雄黄和雌黄）或非特定矿物（富含砷的黄铁矿）的形式存在。这些矿物的不稳定性导致富含砷的矿山排水和废石堆浸出液进入地表水或地下水。对该地区三个最重要的汞矿（La Soterraña、Los Rueldos 和 El Terronal）进行了一项研究。流经这些矿区的水系是该地区最重要的河流之一 Cudal 河的支流。这些水中发现了一些砷的高浓度，这些水在三个水文年期间进行了监测，并根据水质指数进行了分类。靠近矿山采样的这些水通常质量较差，碱度低，在某些情况下金属含量高，但随着远离矿山，这些水的质量会有所改善。从 La Soterraña、Los Rueldos 和 El Terronal 矿场进入 Cudal 河的砷平均质量负荷分别评估为：200、12 和 9800 公斤/年。尽管每年持续输入约 10 吨砷，但由于河流的高水流，总砷浓度仍低于分析检测阈值。尽管如此，该砷负荷的很大一部分可能会保留在河底沉积物中，这代表了对水生生态系统污染的潜在风险。
