Groundwater Monitoring in the Eagle Ford: Evaluating Baseline Conditions in a Risk Management Context

Abstract Unconventional Resource (UCR) development requires a robust understanding of baseline conditions and potential for environmental impacts due to its dependence on water and other shared resources, geographic overlap of target locations and the presence of potential receptors. While many operators have committed to monitor groundwater as part of their Environmental Management programs, the value of a monitoring program depends on having a coherent strategy for identifying critical data and implementing program elements in the correct stage of the project lifecycle. Increasingly, operators are also recognizing that implementing a sound groundwater monitoring plan is a key component of their strategy to manage business risk in the rapidly developing shale plays. Using the Eagle Ford shale as a case study, this paper evaluates the emerging industry standard of baseline and on-going groundwater monitoring to assess the potential for impacts to water resources from drilling and hydraulic fracturing. Data sources for this study include publicly-available state and federal agency data, interviews with major operators, and groundwater data collected as part of early lifecycle baseline assessments. Water management programs in UCR development are complicated by factors such as population density, land use, depth and availability of potable or non-potable groundwater, and competition between water users. The challenge for operators has been to develop a monitoring program that is robust enough to manage current and potential future risk, while remaining efficient and flexible enough to accommodate changing development schedules. The monitoring program must be readily modified in response to new data. Recent work in this area has been focused on using risk-based assessments to identify critical areas where monitoring will provide key information on the potential impacts of drilling and hydraulic fracturing operations. Major components of a water monitoring program include developing the risk basis for sample locations, agreeing on the suite of analytes to be monitored, and incorporating the program into the development schedule. This approach helps operators design a "fit-for-purpose" program based on local and regional hydrogeology, surrounding land use and potential sources of contamination, the presence of historical oil and gas operations, current groundwater use, and the presence of receptors. Such a program provides operators with the critical groundwater data and risk management information necessary to address stakeholder concerns, maintain schedule, transfer water resource infrastructure for future use later in the development lifecycle, and, ultimately, maintain this component of their social license to operate.