Geosynthetic liners for sustainable development of Arctic mineral resources

2015年，矿产资源开采为加拿大经济贡献了560亿美元。预计仅在未来十年，加拿大北极地区就将有超过80亿美元的新矿产资源开发。这些活动涉及产生受污染的水，需要以可持续的方式进行管理，以维持和帮助发展这一至关重要的经济活动，同时保护地表水和地下水供应以及敏感的北极生态系统。这些水包括产酸废石堆的径流和采矿过程结束时产生的称为尾矿的废物，这些废物主要由土壤颗粒、可溶盐和水组成。通常使用大堆或蓄水池来容纳这些废物。为了最大限度地减少地下水和地表水污染，必须以安全但经济可行的方式加以控制。土工膜(塑料薄膜厚度通常为1-2.5毫米)和土工合成粘土衬垫(包裹在两层纺织品之间的5-7毫米厚的粘土层)被认为是废石堆顶部(即作为一个工程盖子，将水和空气在废物中的移动限制在可以忽略的水平)和尾矿库底部(即作为一个工程屏障，以减少污染物逃逸到周围环境的数量)的衬垫。这些土工合成衬垫已被用于显著加强城市垃圾填埋场的环境保护。然而，几乎没有具体的数据来支持它们在北极条件下的合理设计和长期评估，特别是考虑到全球气候变化的影响。需要进行研究，以评估预计会有多少液体通过班轮泄漏，以及班轮在北极应用中暴露在化学品和物理压力下时会持续多长时间。大学研究人员、工程顾问和土工合成材料制造商之间的这一伙伴关系的目的是为土工合成衬垫的设计建立科学可靠的技术基础，以实现北极矿产资源的可持续开发。这项研究将在对加拿大具有重要经济和环境意义的领域为六名高素质人员提供专门培训。

Extraction of mineral resources contributed $56 billion to Canada's economy in 2015. More than $8 billion in new mineral resource development is anticipated in the next decade alone in the Canadian Arctic. These activities involve generation of contaminated water that needs to be managed in a sustainable manner to maintain and help grow this vital economic activity while protecting surface and ground water supplies, and the sensitive Arctic ecosystem. These waters include runoff through acid generating waste rock piles and end of process wastes from mining called tailings, which largely consist of soil size particles, soluble salts and water. Large piles or impoundments are commonly used to contain these wastes. To minimize ground and surface water contamination they need to be contained in a safe but economically feasible manner. Geomembranes (plastic sheets typically 1-2.5 mm thick) and geosynthetic clay liners (a 5-7 mm thick layer of clay encapsulated between two layers of textile) are being considered as liners on top of waste rock piles (i.e., as an engineered cover to limit the movement of water and air through the waste to a negligible level) and on the bottom of tailings impoundments (i.e., as an engineered barrier to reduce the quantity of contaminants from escaping into the surrounding environment). These geosynthetic liners have been used to significantly enhance environmental protection at municipal landfills. However, there is little specific data to permit their rational design and long-term assessment in Arctic conditions, especially considering the effects of global climate change. Research is needed to allow an assessment of how much fluid may be expected to leak through the liner and how long the liner will last when exposed to the chemicals and physical stresses in Arctic applications. The aim of this partnership between university researchers, engineering consultants, and geosynthetic manufacturers is to establish a scientifically sound technical basis for the design of geosynthetic liners to enable the sustainable development of Arctic mineral resources. The research will provide specialized training for six highly qualified personnel in an area of economic and environmental importance for Canada.