Advancing non-invasive geoelectrical methods for imaging soil and groundwater contaminants

推进非侵入性地电方法对土壤和地下水污染物进行成像

• 批准号: RGPIN-2020-06427
• 负责人: Power, Christopher
• 金额: $ 1.89万
• 依托单位: University of Western Ontario
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=718309
• 关键词: Advancing; non; invasive; geoelectrical; methods

Contamination of soil and groundwater by hazardous chemicals, including chlorinated solvents and coal tar (known as dense nonaqueous phase liquids (DNAPLs)) and other anthropogenic chemicals such as per- and polyfluoroalkyl substances (PFAS), remains a serious problem worldwide. Approximately 24,000 federal contaminated sites exist in Canada alone, including former industrial lands, decommissioned refineries, and abandoned gas stations. In 2019, the Federal Contaminated Sites Action Plan was renewed for 15 years, with the federal government pledging $1.16 billion for the first five years (2020 to 2024). Of this, $1.05 billion has been assigned to remediate contaminated sites. Successful remediation requires accurate knowledge on where the contaminants are, and how quickly they are being removed. Since conventional methods, including boreholes and monitoring wells, are intrusive, costly and provide limited information, rapid and cost-effective methods providing continuous information on the subsurface are highly desirable. Geoelectrical techniques are non-invasive imaging methods that can look' below the surface, much like an MRI scan, to detect features of interest. These techniques, which include electrical resistivity tomography (ERT) and induced polarization (IP), are seeing increasing application in environmental investigations. Since they measure the spatial variation of electrical properties, and contaminants typically have distinct electrical properties relative to groundwater (i.e., resistive DNAPL, conductive AMD), geoelectrical techniques have outstanding potential as investigative tools at contaminated sites. However, their common application has not been realized, due in part to the lack of tools and experience in interpreting geoelectrical responses from heterogeneous contaminant distributions in the subsurface. The ultimate goal of this research program is to establish geoelectrical techniques as field-proven tools for contaminated site investigations, including characterization and remediation activities. ERT is the most mature technique but requires critical research to jump to pilot-scale field trials. IP is newer and exciting but needs fundamental work to prove its value for certain contaminants and scenarios. In the short-term, this research program will focus on: (i) building the foundation for IP as a technique for mapping contaminated sites, (ii) translating initial success of ERT to pilot test field implementation, and (iii) launching geoelectrical techniques for mapping key emerging contaminants. The program is timely and is supplemented by the recent, transformative improvements occurring in geoelectrical imaging. It is expected to be a game changer in the remediation industry, leading to significant benefits to the Canadian environment and economy. Furthermore, it will train 3 MESc students, 2 PhD students and 5 undergraduate students and prepare them for key positions in the fast-growing environmental sector.

危险化学品（包括氯化溶剂和煤焦油（称为浓非水相液体 (DNAPL)）以及全氟烷基物质和多氟烷基物质 (PFAS) 等其他人为化学品对土壤和地下水的污染仍然是世界范围内的一个严重问题。仅加拿大境内就有大约 24,000 个联邦污染场地，包括以前的工业用地、退役的炼油厂和废弃的加油站。 2019年，《联邦污染场地行动计划》续签15年，联邦政府承诺前五年（2020年至2024年）拨款11.6亿美元。其中，10.5 亿美元已用于修复受污染场地。 成功的修复需要准确了解污染物的位置以及去除污染物的速度。由于传统方法（包括钻孔和监测井）具有侵入性、成本高昂且提供的信息有限，因此非常需要快速且经济有效的方法来提供地下的连续信息。地电技术是非侵入性成像方法，可以像 MRI 扫描一样观察地表以下，以检测感兴趣的特征。这些技术，包括电阻率断层扫描 (ERT) 和诱发极化 (IP)，在环境调查中的应用越来越多。由于它们测量电特性的空间变化，并且污染物通常具有相对于地下水不同的电特性（即电阻 DNAPL、导电 AMD），因此地电技术作为污染场地的调查工具具有突出的潜力。然而，它们的共同应用尚未实现，部分原因是缺乏解释地下异质污染物分布的地电响应的工具和经验。 该研究计划的最终目标是建立地电技术作为污染场地调查（包括表征和修复活动）经过现场验证的工具。 ERT 是最成熟的技术，但需要进行关键研究才能进行中试规模的现场试验。 IP 较新且令人兴奋，但需要基础工作来证明其对某些污染物和场景的价值。短期内，该研究计划将侧重于：(i) 为 IP 作为污染场地测绘技术奠定基础，(ii) 将 ERT 的初步成功转化为试点试验场实施，以及 (iii) 推出地电技术用于绘制关键新兴污染物的地图。 该计划非常及时，并得到了地电成像领域最近发生的变革性改进的补充。预计它将改变修复行业的游戏规则，为加拿大的环境和经济带来重大利益。此外，还将培训 3 名理学硕士学生、2 名博士生和 5 名本科生，为快速发展的环境领域的关键职位做好准备。