A contaminated industrial waste site in Washington State (USA) containing buried, metallic-waste storage tanks, pipes, and wells, was evaluated to determine the feasibility of monitoring groundwater remediation activities associated with an underlying perched aquifer system using electrical resistivity tomography. The perched aquifer, located ~65 m below ground surface and ~10 m above the regional water table, contains high concentrations of nitrate, uranium, and other contaminants of concern from past tank leaks and intentional releases of wastes to surface disposal sites. The extent of the perched water aquifer is not well known, and the effectiveness of groundwater extraction for contaminant removal is uncertain, so supplemental characterization and monitoring technologies are being evaluated. Numerical simulations of subsurface flow and contaminant transport were performed with a highly resolved model of the hydrogeologic system and waste site infrastructure, and these simulations were used as the physical basis for electrical resistivity tomography modeling. The modeling explicitly accounted for metallic infrastructure at the site. The effectiveness of using surface electrodes versus surface and horizontal subsurface electrodes, for imaging groundwater extraction from the perched water aquifer, was investigated. Although directional drilling is a mature technology, its use for electrode emplacement in the deep subsurface under a complex industrial waste site via horizontal wells has not yet been demonstrated. Results from this study indicate that using horizontal subsurface electrode arrays could significantly improve the ability of electrical resistivity tomography to image deep subsurface features and monitor remediation activities under complex industrial waste sites.

对华盛顿州（美国）一个污染严重的工业垃圾场进行了评估，其中包含埋藏的金属废物储罐，管道和水井，以确定使用电阻层析成像技术监测与下伏的含水层系统相关的地下水修复活动的可行性。栖息的含水层位于地面以下约65 m，区域地下水位以上约10 m，其中包含高浓度的硝酸盐，铀和其他有害污染物，这些污染物是由于过去的储罐泄漏和有意释放到地表处置场所而引起的。栖息的含水层的程度尚不为人所知，并且地下水提取对污染物去除的有效性尚不确定，因此正在评估补充性表征和监测技术。利用高度解析的水文地质系统和废物现场基础设施模型进行了地下流动和污染物运移的数值模拟，这些模拟被用作电阻层析成像建模的物理基础。该建模明确考虑了现场的金属基础设施。研究了使用表面电极相对于表面和水平地下电极对从栖息的含水层提取地下水进行成像的有效性。尽管定向钻探是一项成熟的技术，但尚未证明其可用于通过水平井将电极放置在复杂的工业废料场下的深层地下。