Tailing migration though geomembrane holes

以安全和环境可接受的方式管理尾矿(资源开采后产生的废物)对于加拿大这一重要经济部门的持续活动至关重要--2014年价值570亿美元。越来越多地，从尾矿向环境中长期排放污染物需要进行评估。申请者和行业合作伙伴KCB在NSERC的支持下进行的最新研究表明，使用土工膜衬垫在减少尾矿向周围环境的地下渗漏方面具有显著优势。行业资金被用来进行第一次此类实验，以测量一系列实际条件下的渗漏(通过土工膜上的孔的流体流动)，而NSERC资金被用于进行测量，以调查当地的土壤行为，并进行详细的数值分析，以了解测量的流动。工程师现在可以使用这一新知识来计算实际情况下的渗漏量，在这些情况下，尾矿和基础土壤之间的过滤器兼容性是确定的。工业现在需要知道在更实际的情况下，当土壤颗粒可能从尾矿迁移到地基土壤中时会发生什么。拟议的研究将利用行业资金进行根本上的新实验，以评估尾矿在边缘稳定的情况下的流动性；换句话说，在传统过滤理论的“灰色区域”内，尾矿细粉通过土膜孔的一些迁移是否会导致局部稳定的条件或尾矿的灾难性损失？NSERC的资金将用于：提供对细粒迁移机制的更详细了解(很可能不同于传统的过滤理论，因为土工膜缺陷附近的流动模式更复杂，渗流速度变化大)，量化尾矿细粒迁移到地基土壤中的距离，并研究局部但稳定的细粒迁移如何影响渗漏率。这项新的研究将为尾矿管理提供更有效、更经济的环境保护，并将为硕士和本科生提供高级培训。

Management of mine tailings (waste generated after resource extraction) in both a safe and environmentally acceptable manner is essential for continued activity in this important sector of Canada's economy-worth $57B in 2014. Increasingly, the long-term discharge of contaminants from the tailings into the environment requires assessment. Recent research by the applicants and industry partner KCB-enabled by NSERC-demonstrated the significant benefit of using a geomembrane liner at reducing subsurface seepage from the tailings into the surrounding environment. Industry funding was used to conduct first-of-their-kind experiments to measure leakage (fluid flow through a hole in the geomembrane) for a range of practical conditions, while NSERC funding was used to conduct measurements to investigate local soil behaviour and detailed numerical analysis to understand the measured flows. Engineers can now use this new knowledge to calculate leakage for practical cases where filter compatibility between the tailings and underlying foundation soil is certain. Industry now needs to know what may happen in the many more practical cases when there may be some migration of soil particles from the tailings into the foundation soil. The proposed research will use industry funding to conduct fundamentally new experiments to assess mobility of tailings for marginally stable cases; in other words, within the "grey-area" of conventional filtration theory, does some migration of tailings fines through the geomembrane hole lead to locally-stable conditions or catastrophic loss of tailings? NSERC funding will be used to: provide more detailed insight into the mechanisms of fines migration (most likely different to conventional filtration theory because of the more complex flow pattern and large variation is seepage velocities near the geomembrane defect), quantify of how far tailing fines migrate into foundation soil, and examine how local but stable fines migration affects the leakage rate. The new research will enable more effective and economical environmental protection for mine tailings management and will provide advanced training for a Masters and an undergraduate student.