Environmental Issues and Answers Related to Shale Gas Development

Abstract

Abstract In the past decade, new advances in hydraulic fracturing techniques, in combination with horizontal drilling, have dramatically increased the production of natural gas from tight shale deposits that were previously considered uneconomical to produce. Today, over 1 million oil and gas wells have been hydraulically fractured in the United States, many in areas without a long history of oil and gas development. The lack of existing oil and gas related infrastructure in these areas has presented new challenges for water supply and wastewater disposal. This paper reviews key environmental issues associated with shale gas development and provides an overview of how these issues are currently being addressed by industry and regulatory stakeholders in the United States. Environmental concerns related to shale gas development that are addressed in our evaluation include: Impacts to groundwater qualityWater usageProper disposal of flowback waterAir quality impactsSeismic EventsImpacts of trucking and other transportation Although significant public and regulatory concern has been expressed regarding the potential effects of the hydraulic fracturing process on water resources, micro-seismic mapping and empirical data show that the transport of fracturing fluids or gases through hydraulically induced fractures into shallow drinking water aquifers has not occurred. Rather, in the rare cases when such water quality impacts do occur, they are very localized and are more commonly related to cement integrity problems or casing leaks in the vertical wellbore of shale gas wells. The increased focus on shale gas development has resulted in more environmentally-friendly operations. Specifically, sustainability and water management tools are being implemented successfully by many operators to ensure that potential environmental impacts are being mitigated upfront as part of the planning process. Knowledge of previous technical challenges and the techniques for the implementation of sustainable processes will be important tools for stakeholders in areas where shale gas development is in its early stages, such as Argentina, Mexico, and Colombia.