The Role of Gases in Groundwater Contamination and Remediation

气体在地下水污染和修复中的作用

• 批准号: RGPIN-2016-04803
• 负责人: Mumford, Kevin
• 金额: $ 1.97万
• 依托单位: Queen's University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=660417
• 关键词: Role; Gases; Groundwater; Contamination; Remediation

Groundwater is a vital natural resource. Approximately 10 million Canadians rely on groundwater as a source of drinking water. It is also an important link between surface water and deeper regional systems, and is a source of water for Canadian industries, including agriculture and oil and gas. The quality of our groundwater is threatened by contamination. There are tens of thousands of contaminated sites in Canada, many of which are brownfield properties located in urban centres and along waterfronts. The cost to clean up these sites is substantial, and likely totals tens of billions of dollars. Gases in the subsurface play an important, but often underappreciated, role in groundwater contamination. For example, gases can be created naturally or by remediation technologies, and they affect the flow of groundwater (by reducing permeability) as well as the transport and reaction of contaminants (by mass transfer between the gas and groundwater). Gases can also be contaminants themselves. For example, the rapid increase in shale gas extraction has led to increased concern over environmental impacts, including the contamination of drinking water aquifers by methane gas.***The proposed research will consist of a coordinated program of laboratory experiments (bench-scale columns and flow cells) combined with numerical modelling to investigate fundamental mechanisms across multiple disciplines. A team of five graduate students (two Doctoral and three Master's) will develop methods to inject dissolved gas or create trapped gas bubbles using chemical reactions to enhance clean-up technologies. They will also investigate the dissolution of methane in groundwater to better understand the effects of gas leakage during shale gas extraction, and will develop novel characterization methods for the laboratory and field. This research will:***(a) Establish the scientific basis for new technologies to enhance groundwater clean-up using thermal remediation and gas emplacement;***(b) Provide the detailed data required to validate advanced numerical models of contaminant transport in groundwater where gases are present;***(c) Develop new techniques for measuring groundwater gases in the laboratory (based on high-resolution visualization) and the field (based on cryogenic coring); and***(d) Train graduate students to tackle emerging problems in groundwater contamination and remediation.***The results of this research will be used by both researchers and industry in Canada to improve the clean-up of contaminated sites, contribute to the development of best-practices for monitoring shale gas extraction, and help site investigators more accurately measure dissolved gases and gas bubbles in groundwater. Overall, these results will support the long-term research vision of improving our understanding of gas migration and mass transfer in contaminated groundwater systems.***

地下水是一种重要的自然资源。大约有1000万加拿大人依靠地下水作为饮用水来源。它也是地表水和更深层次的区域系统之间的重要纽带，也是加拿大工业的水源，包括农业和石油和天然气。我们的地下水质量受到污染的威胁。加拿大有数以万计的受污染地点，其中许多是位于市中心和海滨的棕地物业。清理这些网站的成本是巨大的，可能总计数百亿美元。地下水中的气体在地下水污染中扮演着重要但往往被忽视的角色。例如，气体可以是自然产生的，也可以通过修复技术产生，它们会影响地下水的流动(通过降低渗透率)以及污染物的传输和反应(通过气体和地下水之间的传质)。气体本身也可能是污染物。例如，页岩气开采的快速增长导致了人们对环境影响的日益关注，包括甲烷气体对饮用水含水层的污染。*拟议的研究将包括一个协调的实验室实验计划(实验室规模的柱和流动池)，并结合数值模拟来研究跨越多个学科的基本机制。一个由五名研究生(两名博士和三名硕士)组成的团队将开发注入溶解气体或利用化学反应产生被困气泡的方法，以加强清理技术。他们还将调查地下水中甲烷的溶解情况，以更好地了解页岩气开采过程中天然气泄漏的影响，并将为实验室和现场开发新的表征方法。这项研究将：*(A)为利用热修复和气体埋设加强地下水净化的新技术奠定科学基础；*(B)提供必要的详细数据，以验证存在气体的地下水中污染物迁移的高级数值模型；*(C)开发在实验室(基于高分辨率可视化)和现场(基于低温取心)测量地下水气体的新技术；和*(D)培训研究生解决地下水污染和修复方面新出现的问题。*这项研究的结果将被加拿大的研究人员和工业界用来改善受污染场地的清理，有助于制定监测页岩气开采的最佳做法，并帮助场地调查人员更准确地测量地下水中溶解的气体和气泡。总体而言，这些结果将支持长期研究愿景，即提高我们对受污染地下水系统中气体迁移和质量转移的理解。