The environmental impact of the Mount Polley mine tailings spill and related clean-up operations, British Columbia, Canada

自1970年以来，全世界发生了70多起重大尾矿坝蓄水失败的报告，其中许多对生态系统造成了长期损害，对生活在受影响河流旁边并依靠受影响河流获得食物和生计的社区造成了重大影响，并造成1000多人死亡。由于世界各地采矿作业的数量不断增加，而且由于气候变化，这些类型的环境越来越容易受到极端事件的影响，这种尾矿坝坍塌造成的环境风险正在增加。拟议的研究旨在确定加拿大不列颠哥伦比亚省波利山金矿和铜矿2014年8月4日波利山尾矿蓄水失败的环境和地貌影响。波利山的溢漏是有记录以来最大的溢漏之一（1 000万立方米的水和450万立方米的含砷、铜、镍和铅尾矿），其规模与最近在西班牙Aznalcollar（1998年，130万立方米尾矿）和匈牙利Ajkai（2010年，600 - 700万立方米尾矿）发生的大规模溢漏相同。在溃坝事故中，波利山灾难的独特之处在于，尾矿中含有不寻常的污染物混合物（砷、铜、金、锰、镍、铅、钒），使人们能够在一次事故中研究各种污染物的影响。此外，该场址位于一个受严冬影响的山区森林集水区内，这为研究春季积雪融化造成的大量溢出尾矿的再流动提供了机会。目前还没有关于这种尾矿在土壤和沉积物中的短期至长期（数月至数年）行为以及清理作业对其在这类河流环境中行为的影响的数据。目前迫切需要资金，因为确定这种地球化学行为需要立即确定溢出的尾矿以及受溢出影响的土壤和沉积物的特征。拟议的研究将通过建立废物的地球化学稳定性和反应性的模型，并通过确定泄漏和相关清理行动对陆地和水生环境的长期恢复的影响，填补这一知识空白。为此，将建立一个关于溢出尾矿和沉积物以及受溢出影响的土壤的物理、地球化学和矿物学数据库。该数据集将为量化金铜尾矿的稳定性和反应性提供重要的基线，并允许预测波利山泄漏和后续清理作业的长期环境影响。还将在2015年春季融雪之前（2014年秋季）和之后进行空中和地面地貌调查，以确定沉积物预算和下游受影响地区的污染物通量估计数。结果将是第一次从一个独特的泄漏与一个不寻常的混合污染物位于山区，森林集水区，受严冬与突出的春季融雪洪水。

Since 1970, over 70 major reported failures of tailings dam impoundments have occurred around the world, and many of these have resulted in long-term damage to ecosystems and significant impact on communities that live beside and rely on impacted rivers for food and livelihood, and the loss of over 1000 lives. The environmental risks from such tailings dam failures are increasing because of the growing number of mining operations world-wide and because of the growing vulnerability of these types of environments to extreme events because of climate change. The proposed research aims to determine the environmental and geomorphological impacts of the August 4th 2014 Mount Polley tailings impoundment failure at the Mount Polley gold and copper Mine in British Columbia, Canada. The Mount Polley spill is one of the largest ever recorded (10 million m3 of water and 4.5 million m3 of arsenic-, copper-, nickel- and lead-bearing tailings), on the same scale as recent large spills in Aznalcollar, Spain (1998, 1.3 million m3 of tailings) and Ajkai, Hungary (2010, 6-7 million m3 of tailings). Among dam failures, the Mount Polley disaster is unique in that that the tailings contain an unusual mixture of contaminants (arsenic, copper, gold, manganese, nickel, lead, vanadium) enabling the impacts of a wide range of contaminants to be studied in a single event. In addition, the site is located within a mountainous forested catchment that is affected by severe winters, providing an opportunity to study remobilization of the very large quantities of spilled tailings due to the spring melting of snow. No data currently exist on the short- to long-term (months to years) behaviour of such tailings in soils and sediments and the effects of clean-up operations on their behaviour in this type of river environment. There is an urgent need for funding as establishing this geochemical behaviour requires immediate characterization of the spilled mine tailings and of the soils and sediments impacted by the spill. The proposed research will fill this knowledge gap by modelling the geochemical stability and reactivity of the wastes and by establishing the impacts of the spill and related clean-up operations on longer-term recovery of terrestrial and aquatic environments. This will be achieved by producing a physical, geochemical, mineralogical database for spilled tailings and sediments and soils affected by the spill. This dataset will provide an essential baseline for quantifying the stability and reactivity of gold-copper tailings, and allow the long-term environmental impacts of the Mount Polley spill and subsequent clean-up operations to be predicted. Airborne and ground-based geomorphological surveys will also be carried out prior to (in autumn 2014), and after the spring 2015 snow melt, to develop a sediment budget and an estimated contaminant flux to downstream affected areas. The results will be the first from a unique spill with an unusual mixture of contaminants located within a mountainous, forested catchment, affected by severe winters with prominent spring snow melt floods.