Ali A, Strezov V, Davies P, Wright I
Department of Environmental Sciences, Faculty of Science and Engineering, Macquarie University, Sydney, NSW, 2109, Australia.
School of Science and Health, University of Western Sydney, Locked Bag 1797, South Penrith, Sydney, NSW, Australia.
Environ Monit Assess. 2017 Aug;189(8):408. doi: 10.1007/s10661-017-6110-4. Epub 2017 Jul 21.
The extraction of coal and coal seam gas (CSG) will generate produced water that, if not adequately treated, will pollute surface and groundwater systems. In Australia, the discharge of produced water from coal mining and related activities is regulated by the state environment agency through a pollution licence. This licence sets the discharge limits for a range of analytes to protect the environment into which the produced water is discharged. This study reports on the impact of produced water from coal mine activities located within or discharging into high conservation environments, such as National Parks, in the outer region of Sydney, Australia. The water samples upstream and downstream from the discharge points from six mines were taken, and 110 parameters were tested. The results were assessed against a water quality index (WQI) which accounts for pH, turbidity, dissolved oxygen, biochemical oxygen demand, total dissolved solids, total phosphorus, nitrate nitrogen and E .coli. The water quality assessment based on the trace metal contents against various national maximum admissible concentration (MAC) and their corresponding environmental impacts was also included in the study which also established a base value of water quality for further study. The study revealed that impacted water downstream of the mine discharge points contained higher metal content than the upstream reference locations. In many cases, the downstream water was above the Australia and New Zealand Environment Conservation Council and international water quality guidelines for freshwater stream. The major outliers to the guidelines were aluminium (Al), iron (Fe), manganese (Mn), nickel (Ni) and zinc (Zn). The WQI of surface water at and downstream of the discharge point was lower when compared to upstream or reference conditions in the majority of cases. Toxicology indices of metals present in industrial discharges were used as an additional tool to assess water quality, and the newly proposed environmental water quality index (EWQI) lead to better trend in the impact of coal and coal seam gas mining activities on surface water quality when compared to the upstream reference water samples. Metal content limits were based on the impact points assigned by the Agency for Toxic Substances and Disease Registry, USA. For environmental and health impact assessment, the approach used in this study can be applied as a model to provide a basis to assess the anthropogenic contribution from the industrial and mining activities on the environment.
煤炭和煤层气（CSG）的开采会产生采出水，如果处理不当，将会污染地表水和地下水系统。在澳大利亚，煤矿开采及相关活动产生的采出水排放由州环境机构通过污染许可证进行监管。该许可证设定了一系列分析物的排放限值，以保护环境免受采出水排放的影响。本研究报告了位于澳大利亚悉尼外围地区高保护环境（如国家公园）内或向其排放的煤矿活动产生的采出水的影响。采集了六个煤矿排放点上下游的水样，并检测了110项参数。根据水质指数（WQI）对结果进行评估，该指数考虑了pH值、浊度、溶解氧、生化需氧量、总溶解固体、总磷、硝酸盐氮和大肠杆菌。该研究还包括基于痕量金属含量与各国最大允许浓度（MAC）及其相应环境影响的水质评估，并确定了水质的基准值以供进一步研究。研究表明，矿井排放点下游的受影响水体所含金属含量高于上游参考地点。在许多情况下，下游水体超出了澳大利亚和新西兰环境保护委员会以及国际淡水溪流水质指南的标准。超出指南标准的主要金属是铝（Al）、铁（Fe）、锰（Mn）、镍（Ni）和锌（Zn）。在大多数情况下，排放点及下游地表水的WQI低于上游或参考条件下的WQI。工业排放中金属的毒理学指标被用作评估水质的额外工具，与上游参考水样相比，新提出的环境水质指数（EWQI）能更好地反映煤炭和煤层气开采活动对地表水水质的影响趋势。金属含量限值基于美国有毒物质和疾病登记局指定的影响点。对于环境和健康影响评估，本研究中使用的方法可作为一个模型，为评估工业和采矿活动对环境的人为贡献提供依据。
