Developing novel in situ methods to monitor and quantify groundwater storage changes in cold regions

背景：振动丝压计（VWPs）可用于测定原位孔隙水压力和估计流动模式；然而，收集到的数据没有得到充分利用。利用vwp来确定和量化地下水储量变化的新型数据采集和分析方法可以通过在各种环境下的各种尺度上进行测试来实现。目的：本研究计划的长期目标是通过开发和应用新的原位方法来增加对地下水储存变化的基本了解。这将扩展现有的理论和基础设施，以开发和验证新的方法，通过量化大型和小型集水区的储水量变化，帮助消除对水平衡的猜测。将采用现场、实验室和计算技术相结合的综合方法，通过三个短期目标（sto）来实现这一目标：STO-1：开发一种经过现场验证的方法来描绘饱和和非饱和带的储水变化，并确定响应自然和人为强迫的特征孔隙压力行为。将在多个深度和地层中评估地质称重溶渗仪方法量化承压含水层和含水层储水变化的有效性。目前安装在SK的五个站点的敏感vwp将用于校准地质溶土层计捕获区域，并比较这些方法在不同材料，深度和位置下的有效性，以监测土壤湿度（地下水储存）的变化，并定义地质称重溶土层计应用中的空间变异性。STO-2：在实验室开发一种方法或技术，在完全或部分冷冻的材料中安装高灵敏度的vwp。将设计并执行实验室规模的实验，以调查在完全或部分冻结的地质材料中安装仪器的潜力。热特性的数值模拟和VWP承受大温度变化的能力将被评估。STO-3：通过调查易受攻击或被积极利用的环境来评估开发的方法。在STO-1和sto -2中制定的方法将适用于很少使用或打算用于不同用途的原地vwp环境，包括永久冻土区（STO-3a）和废石堆和尾矿设施（STO-3b）。影响：所获得的知识将提供实际有效的方法来监测地下水对自然和人为强迫的反应，并有助于约束水平衡模型。应用包括改善矿区的水管理技术、农业部门的土壤湿度监测、寒冷地区永久冻土融化评估以及环境地下水监测项目。研究结果还将为未来的数据需求提供信息，以促进加拿大和全球的地下水管理和水安全。

Background: Vibrating wire piezometers (VWPs) can be used to determine in situ pore water pressure and estimate the flow pattern; however, the data collected are vastly underutilized. Novel data acquisition and analysis approaches using VWPs to determine and quantify groundwater storage changes can be achieved by testing these methods at various scales over a wide range of environments. Objectives: The long-term objective of this research program is to increase fundamental understanding of groundwater storage changes by developing and applying novel in situ methods. This will expand upon current theory and infrastructure to develop and validate new methods to help eliminate guesswork in water balances by quantifying changes in water storage in large- and small-scale catchment areas. An integrative approach combining field, laboratory, and computational techniques will be used to achieve this goal through three short-term objectives (STOs): STO-1: Develop a field-verified method to delineate water storage changes in saturated and unsaturated zones and determine characteristic pore pressure behaviour in response to natural and anthropogenic forcings. The effectiveness of the geo-weighing lysimeter approach for quantifying water storage change in confined aquifers and aquitards will be evaluated at multiple depths and formations. Sensitive VWPs currently installed at five sites in SK will be used to calibrate the geolysimeter capture area and compare the effectiveness of such methods in different materials, depths, and locations to monitor changes in soil moisture (groundwater storage) and define the spatial variability in the application of geo-weighing lysimeters. STO-2: Develop a method or technique in the laboratory to install highly sensitive VWPs in fully or partially frozen material. Lab-scale experiments will be designed and executed to investigate the potential of installing instrumentation in fully or partially frozen geomaterial. Numerical modeling of the thermal characteristics and the ability of the VWP to withstand large temperature changes will be assessed. STO-3: Evaluate the developed methods by investigating vulnerable or actively exploited environments. Methods developed in STO-1 and -2 will be applied to environments where in situ VWPs are rarely used or intended for different uses, including permafrost regions (STO-3a), and waste rock piles and tailings facilities (STO-3b). Impact: The knowledge gained will provide practical and effective methods to monitor groundwater behaviour in response to natural and anthropogenic forcings and help constrain water balance models. Applications include improving water management techniques for mine sites, soil moisture monitoring in the agriculture sector, assessment of permafrost melting in cold regions, and ambient groundwater monitoring programs. The results will also inform future data requirements to facilitate groundwater management and water security both in Canada and globally.