Área de Geoquímica y Sostenibilidad Minera, Instituto Geológico y Minero de España, Alenza 1, 28003, Madrid, Spain.
Área de Geoquímica y Sostenibilidad Minera, Instituto Geológico y Minero de España, La Calera 1, 28760, Tres Cantos, Madrid, Spain.
Environ Monit Assess. 2020 Mar 23;192(4):247. doi: 10.1007/s10661-020-8199-0.
This work explores the ability of the Spanish Geochemical Database to identify the existence of polluted stream sediments due to the presence of abandoned mine wastes. The mining district of Sierra de Cartagena-La Unión has been used as test area. A total of 18 abandoned tailings facilities were selected and samples were taken for analysis of the content in potential toxic elements. The results were contrasted with geochemical background values in order to identify which geochemical elements could entail anomalies potentially reflected in the Spanish Geochemical Database. For the study area, As, Cd, Pb, and Zn have been identified as potential toxic elements which can be used as geochemical indicators of sediment pollution processes originated in abandoned mine wastes. Furthermore, the correlation between Cd and Zn allows them to be considered as the best indicators of potential sediment contamination. The study of anomaly thresholds, through the analysis of accumulated frequencies of the contents of these elements in the sediments of the Spanish Geochemical Database, allows identifying sediments that may have been contaminated. A Mann-Whitney test contrasting the data of tailings, polluted sediments, and non-polluted sediments has been performed in order to verify differences among these types of samples. In addition, a geospatial analysis has demonstrated a very close relationship between contaminated sediments and the presence of mining wastes upstream. This methodology can be applied to any other mining region, to recognize the possible influence of pollution processes derived from the presence of abandoned mine wastes taking advantage of existing geochemical databases.
本研究旨在探讨西班牙地球化学数据库识别因废弃矿山废物而受到污染的溪流沉积物的能力。为此，选择了卡塔赫纳-拉乌尼翁山脉矿区作为试验区。共选取了 18 个废弃尾矿库，并对其中的潜在有毒元素含量进行了采样分析。然后将这些结果与地球化学背景值进行了对比，以确定哪些地球化学元素可能会在西班牙地球化学数据库中产生潜在的异常。对于研究区域，砷、镉、铅和锌被确定为潜在的有毒元素，它们可用作源自废弃矿山废物的沉积物污染过程的地球化学指标。此外，镉和锌之间的相关性使它们可以被视为潜在沉积物污染的最佳指标。通过分析西班牙地球化学数据库中这些元素在沉积物中的含量的累积频率，可以研究异常阈值，从而识别可能受到污染的沉积物。为了验证这些类型的样品之间的差异，对尾矿、污染沉积物和非污染沉积物的累积频率数据进行了曼-惠特尼检验。此外，地理空间分析表明，受污染的沉积物与上游存在的采矿废物之间存在非常密切的关系。这种方法可以应用于任何其他矿区，以利用现有的地球化学数据库，识别可能源于废弃矿山废物存在的污染过程的影响。
