Coupling of physical and bio-geochemical processes in saturated and unsaturated subsurface systems.

饱和和不饱和地下系统中物理和生物地球化学过程的耦合。

• 批准号: RGPIN-2014-06610
• 负责人: Amos, Richard
• 金额: $ 2.7万
• 依托单位: Carleton University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=589115
• 关键词: Coupling; physical; bio; geochemical; processes

The contamination of groundwater from mining, industrial and other anthropogenic activities threatens potable water supplies and ecosystem health. The transport and fate of contaminants in groundwater and in unsaturated soils often involves complex biogeochemical reactions coupled to physical transport and attenuation processes. Reactive transport models provide a means of quantifying these processes, providing a means of analyzing complex data sets and providing insights into the underlying mechanisms of contaminant transport and attenuation. The long-term objectives of the research are to better understand and quantify coupled biogeochemical and physical processes, and the effect of this coupling on contaminant transport and attenuation, through the development of reactive transport models. The key areas for development will include: 1) Simulation of nano-particle and colloid transport and reactivity: Colloids are particles with dimensions measuring in the nano-meter scale. Inorganic and organic colloids can interact with metal-bearing wastes and potentially facilitate their transport in the environment. A reactive transport model will be developed to simulate colloid transport and geochemical interactions, and the model will be used to simulate field and laboratory column experiments to gain a better understanding of colloid-associated metal transport. 2) Simulation of stable isotope fractionation in multi-phase systems: A reactive transport model will be developed to simulate the fractionation of carbon isotopes in methane and carbon in dissolved and vapour phase gases, including gas bubbles. The model will be used to simulate the degradation of contaminants at an oil spill site near the town of Bemidji, MN, providing a better understanding of degradation rates, and transport and attenuation mechanisms. In addition, laboratory tank experiments will be conducted to better quantify the gas/water interactions at the water table. 3) Coupling of physical and geochemical processes in mine waste: The prediction of drainage quality from waste-rock piles is an important aspect of mine planning and permitting. A reactive transport model will be developed to couple thermal, hydrological and geochemical interactions in waste-rock dumps. The model will be applied to data collected at the Diavik Diamond Mine in the Northwest Territories to better understand the processes controlling water quality. 4) Mechanistic simulation of gases and gas bubble movement in contaminated aquifers. A reactive transport model will be developed to provide a better description of gas transport, including the movement of gas bubbles in groundwater. The model will be used to simulate 1) the transport of volatile organic contaminants in groundwater including the vertical transport of gas bubbles due to buoyancy, 2) tritium and organic contaminants in unsaturated materials below and low-level nuclear waste repository, and 3) the entrapment of gas bubbled during recharge below an artificial recharge pond. The proposed research will provide a unique reactive transport model that will provide insight into the movement of contaminants in the subsurface. This insight will aid in the development of cost-effective contaminant stabilization and remediation options that will assist Canadian industry in meeting environmental protection standards. The research will train highly qualified personnel in the development and application of numerical models and provide them with a thorough understanding of contaminant geochemistry and remediation science. These trainees will continue with cutting edge research or will work in industry, managing contamination issues and helping to maintain Canadian companies at the leading edge of the contaminant remediation industry.

采矿，工业和其他人为活动受到地下水的污染威胁着饮用水供应和生态系统健康。地下水和不饱和土壤中污染物的运输和命运通常涉及复杂的生物地球化学反应，并结合物理运输和衰减过程。反应性传输模型提供了一种量化这些过程的方法，提供了一种分析复杂数据集的方法，并提供了对污染物运输和衰减的潜在机制的见解。该研究的长期目标是通过开发反应性传输模型来更好地理解和量化耦合的生物地球化学和物理过程，以及这种耦合对污染物运输和衰减的影响。开发的关键领域将包括： 1）模拟纳米颗粒和胶体的转运和反应性：胶体是粒子在纳米米尺度上测量的颗粒。无机和有机胶体可以与金属废物相互作用，并有可能促进其在环境中的运输。将开发一个反应性传输模型来模拟胶体运输和地球化学相互作用，该模型将用于模拟场和实验室柱实验，以更好地了解胶体相关的金属转运。 2）模拟多相系统中稳定的同位素分馏：将开发一个反应性传输模型，以模拟甲烷中碳同位素和溶解和蒸气相气中的碳同位素的分馏，包括气泡。该模型将用于模拟明尼苏达州Bemidji镇附近的漏油场所的污染物降解，从而更好地了解降解率以及运输和衰减机制。此外，将进行实验室罐实验，以更好地量化地下水位的气体/水相互作用。 3）地雷废物中的物理和地球化学过程的耦合：废料堆的排水质量预测是我的计划和许可的重要方面。将开发一个反应性传输模型，以对废岩垃圾场中的热，水文和地球化学相互作用。该模型将应用于在西北地区的Diavik钻石矿山收集的数据，以更好地了解控制水质的过程。 4）在受污染的含水层中的气体和气泡运动的机械模拟。将开发一个反应性传输模型，以更好地描述气体传输，包括地下水中气泡的运动。该模型将用于模拟1）地下水中挥发性有机污染物的运输，包括由于浮力而导致的气泡垂直运输，2）在不饱和材料下的tritium和有机污染物，下面的不饱和核废料存储库，以及3）3）在恢复后，燃气的诱捕物在​​恢复下方的胶水中，在人工灌溉过程中被固定在艺术品人工ponderge pond。 拟议的研究将提供一个独特的反应运输模型，该模型将洞悉地下污染物的运动。这种见解将有助于发展具有成本效益的污染物稳定和补救选择，这将有助于加拿大行业达到环境保护标准。该研究将在数值模型的开发和应用中培训高素质的人员，并为他们提供对污染物地球化学和修复科学的透彻理解。这些受训者将继续进行最先进的研究，或者将在行业中工作，管理污染问题并帮助将加拿大公司维持在污染物补救行业的领先地位。