ABSTRACT
This chapter discusses the role of analytical chemistry and recent advancements in characterizing potential contaminants arising from oil and gas production activities.
Natural gas has recently emerged as an abundant, economic, and clean source of energy. It has helped to reduce CO2 emissions and curtail the production of industrial chemicals by the power sector.1 Advanced drilling techniques such as hydraulic fracturing and shale acidization have made the extraction of natural gas from previously inaccessible deep shale formations economically advantageous. Hydraulic fracturing uses a mixture of water, proppants, and chemical additives injected at high pressures to create and maintain ssures or fractures in the shale formation to release trapped gases. Shale acidization uses copious amounts of hydrochloric
7.1 Overview ....................................................................................................... 115 7.2 Introduction .................................................................................................. 115 7.3 Target Analytes Related to Unconventional Drilling ................................... 116 7.4 Dissolved Gases ............................................................................................ 117 7.5 Organic Constituents .................................................................................... 119 7.6 Ions and Isotopes ..........................................................................................124 7.7 Summary and Concluding Remarks ............................................................. 128 References .............................................................................................................. 129
and/or hydrouoric acid under low pressures to dissolve sediments of the shale formation to increase the formation permeability for trapped gases. Even with the proven effectiveness of these approaches to liberate sequestered hydrocarbons, they are not without unique environmental risks. Concerns have been raised over their potential impacts on surrounding ground and surface water. Apprehensions over environmental responsibility, alongside the aspiration of using natural gas to lead the United States to attaining energy independence, have driven the need for numerous investigations of relationships between unconventional drilling and groundwater quality.
