Assessing the impacts of climate change on the performance of engineered geobarriers in the Biotron

一些研究得出结论，地球正在变暖，主要是因为人类活动，特别是工业活动造成的温室气体排放增加。国际气候变化专门委员会的各种预测表明，地球的温度可能会上升1.8-4.6 °？到本世纪末。加拿大气候变暖可能会对全国的水量和水质产生负面影响。例如，气候模型预测，到世纪末，安大略西南部冬季气温将上升3- 7摄氏度，夏季气温将上升4- 8摄氏度。评估废物封隔系统对气候变化的脆弱性涉及危险识别和系统暴露于已识别危险的特征，例如可能使封隔系统的组成部分（例如填埋场覆盖层）退化的降水变化。因此，重要的是要评估降水变化对遏制系统的影响，以制定适应战略。该研究计划的目标是调查在世界三个地理和气候区域连续的正常和气候变化温度和降水量下，用于废物遏制（geobarriers）的选定工程土壤屏障的性能：温带气候（伦敦，安大略，加拿大），北极气候（摩尔曼斯克，俄罗斯西北部），和潮湿的热带稀树草原（阿克拉，加纳）。从长远来看，该计划旨在比较正常和气候条件下的覆盖物和衬垫的实验室测量的流体力学，运输和吸附参数的值与天然类似物的值。 该研究将包括在加拿大西部大学对来自伦敦、安大略省和加纳阿克拉垃圾填埋区的未受污染的天然粘土和其他土壤以及来自俄罗斯西北部科拉半岛地区的氧化铁进行表征和测试。土壤将被填充在大型仪器柱（0.65 m3或22.5 ft 3）中，以模拟垃圾填埋场覆盖层和衬垫以及可渗透反应屏障在正常和气候变化温度和降水条件下在西部大学生物技术中心的两级气候室中进行连续冻融和干湿循环。上层可以模拟地面空气温度，而下层可以设置在地面温度。两个级别的测试箱都可以模拟+40 °C至-40 °C的温度范围。还将研究植物（草）根系生长对土壤覆盖物的影响。该计划的最终目标是开发一种方法，将气候变化影响纳入未来废物控制系统的设计或改造现有系统以承受气候变化。该为期五年的项目将培养13名高素质人才：4名博士生、3名硕士生、5名本科生和1名博士后研究员。

A number of studies have concluded that the Earth is getting warmer mostly because of increased greenhouse gas emissions resulting from anthropogenic activities, especially by industry. Various forecasts made by the International Panel on Climate Change suggest the Earth’s temperature could rise by 1.8-4.6 °? by the end of this century. A warming climate in Canada could have negative impacts on water quantity and quality across the country. For example, climate models are predicting a 3-7oC rise in winter temperatures and a 4-8oC rise in summer temperatures in southwestern Ontario by the end of the century. The assessment of a waste containment system’s vulnerability to climate change involves hazards identification and characterization of the system’s exposure to an identified hazard, such as precipitation changes that could degrade components of the containment system (e.g.landfill covers). It is therefore important to assess the effects of precipitation changes on containment systems in order to develop adaptation strategies. The goal of the research program is to investigate the performance of selected engineered soil barriers used for waste containment (geobarriers) under a continuum of normal and climate change temperatures and precipitations in three geographical and climatic regions of the world: temperate climate (London, Ontario, Canada), Arctic climate (Murmansk, Northwest Russia), and humid, tropical savanna (Accra, Ghana). Over the long term, the program seeks to compare values of laboratory measured  hydromechanical, transport and sorption parameters for covers and liners under normal and climate climate conditions to those obtained on natural analogues. The study will involve sampling of uncontaminated natural clay and other soils from landfill areas in London, ON and Accra, Ghana, and iron oxides from the Kola Peninsula area of Northwest Russia for characterization and testing at Western University, Canada. The soils will be packed in large, instrumented columns (0.65 m3 or 22.5 ft3) to simulate landfill covers and liners and permeable reactive barriers subjected to sequential freeze-thaw and wet-dry cycles under normal and climate change temperatures and precipitations in a two-level climate chamber at The Biotron, Western University. The upper level can simulate ground air temperature, while the lower level can be set at the temperature in the ground. Both levels of the chamber can simulate a +40 °C to -40 °C temperature range. The effect of plant (grass) root growth on the soil covers will also be studied. The ultimate goal of the program is to develop a methodology for incorporating climate change impacts into the design of future waste containment systems or retrofit existing systems to endure climate change. The five-year program will train 13 highly qualified personnel: four doctoral, three master’s and five undergraduate students and one postdoctoral fellow.