Studies of Industrial Biotechnology Center, Exact and Natural Science Faculty, Oriente University, Santiago de Cuba, Cuba.
Avignon University, CNRS, IRD, IMBE, Aix Marseille University, Marseille, France.
Environ Sci Pollut Res Int. 2019 Jun;26(16):16366-16377. doi: 10.1007/s11356-019-05030-3. Epub 2019 Apr 13.
The creation of pit lakes is usually an acceptable solution from the landscaping point of view for voids left by discontinued open-pit mines. However, without rehabilitation, these voids represent a potential environmental risk. The aim of the present work was to assess, for the first time, the water quality, i.e., physicochemical characteristics, metal and metalloid (MM) content, and ecotoxicity of the waters of the El Cobre Blue Lagoon, a pit lake formed in an open-pit copper mine in Cuba. Potential effects of rainy season vs. dry season and spatial location (different depths) on water characteristics were considered. Results revealed that water contained was moderately acidic (pH = 4.6 ± 0.2), with high electrical conductivity (EC = 3.02 ± 0.03 mS cm), whatever the season. Dissolved oxygen (DO = 9.9 ± 2.0 mg L), total dissolved solid (TDS = 7003 ± 245 mg L), and sulfate concentration (6556 ± 1410 mg L) in the El Cobre Blue Lagoon water were above acceptable limits for sources of surface water as recommended by Cuban standard (NC 1021:2014). High copper (43.6 ± 1.7 mg L) and manganese (24.1 ± 1.1 mg L) contents were detected. Except for EC, sulfates, chlorides, TDS, nitrates, and phosphates, other physicochemical parameters were stable between dry and rainy seasons (p < 0.05). El Cobre Blue Lagoon waters showed an ecotoxicological impact on Vibrio fischeri. No significant differences were detected between all sampling points in the lake for each parameter monitored for a given time. These first results show the spatial homogeneity but poor quality of waters from El Cobre Blue Lagoon. Remediation processes need to be implemented in order to lessen the human and environmental health risk and favor potential water reuse. We suggest the use of constructed wetlands for water treatment. This preliminary research work can serve to alert Cuban local public authorities to the need to rehabilitate such sites.
矿坑湖的形成通常是废弃露天矿留下的空洞的一种可接受的景观解决方案。然而，如果不进行修复，这些空洞将构成潜在的环境风险。本研究首次评估了古巴一座露天铜矿形成的矿坑湖 El Cobre 蓝湖的水质，包括理化特性、金属和类金属（MM）含量以及水的生态毒性。考虑了雨季和旱季以及空间位置（不同深度）对水特性的潜在影响。结果表明，无论季节如何，湖水呈中度酸性（pH=4.6±0.2），电导率（EC=3.02±0.03 mS cm）较高。El Cobre 蓝湖的溶解氧（DO=9.9±2.0 mg L）、总溶解固体（TDS=7003±245 mg L）和硫酸盐浓度（6556±1410 mg L）均高于古巴标准（NC 1021:2014）推荐的地表水水源的可接受限值。检测到高浓度的铜（43.6±1.7 mg L）和锰（24.1±1.1 mg L）。除了 EC、硫酸盐、氯化物、TDS、硝酸盐和磷酸盐外，旱季和雨季之间其他理化参数都很稳定（p<0.05）。El Cobre 蓝湖的水对发光杆菌（Vibrio fischeri）具有生态毒性影响。在给定时间内，监测的所有参数在湖中的所有采样点之间均未检测到差异。这些初步结果表明，El Cobre 蓝湖的水质具有空间均一性但较差。需要实施修复过程，以降低人类和环境健康风险，并有利于潜在的水再利用。我们建议使用人工湿地进行水处理。这项初步研究工作可以提醒古巴地方当局需要对这些地点进行修复。
