The oil & natural gas exploration and development process involves multiple activities, each of which has the potential for adverse impacts to human health and to the environment. Potential adverse impacts may occur in any media, including groundwater, surface water, air and soil. In particular, recent focus has been on the hydraulic fracturing for unconventional natural gas development. This is certainly of concern; however, all activities need to be considered. This webpage focuses on summarizing oil & natural gas exploration and production activities, along with the associated compounds of concern. We also provide links to other websites and sources of information. Table I, presented below, summarizes the oil & gas drilling activities and some of the most commonly associated compounds. It should be noted that some of those listed do occur naturally, underscoring the importance of having a water quality baseline conducted prior to oil & gas drilling-related activities. TABLE I - Summary of Oil & Gas Drilling Activities & Commonly Associated Compounds
In addition to considering those compounds that are closely associated with oil & gas drilling activities, water quality baselines also need to take into account a compound's mobility and toxicity. For example, most of the volatile organic compounds are both highly mobile and toxic in groundwater. Benzene has a federal maximum contaminant level (MCL) of 5 ug/L. This amounts to approximately 5 drops in an olympic-size swimming pool! Many other volatile organics have similarly low standards. Needless to say, we strongly recommend that the full list of volatile organics be a part of every water quality baseline. Many of the metals also have health-related standards and are commonly a part of oil & gas drilling-derived contamination. These too should be included as a minimum. The following references provide a substantial amount of information regarding oil & gas drilling activities and associated compounds of concern. We strongly recommend that parties interested in this subject matter review these sources. Sources of Additional Information FracFocus, Chemical Disclosure Registry, fracfocus.org Description: Website provides information on hydraulic fracturing compounds, including their use, types, regulations and general information. Schlumberger Limited; Houston, Texas; www.slb.com/openfrac Description: Website provides complete formulations of their OpenFRAC fluids, used for hydraulic fracturing. The Endocrine Disruption Exchange (TEDX); Paonia, Colorado; www.endocrinedisruption.com Description: Homepage of The Endocrine Disruption Exchange, which provides extensive information on endocrine disruptors, associated with natural gas development. U.S. Department of Energy et al. (2009) Modern Shale Gas Development in the United States: A Primer, DE-FG26-04NT15455, http://www.netl.doe.gov/technologies/oil-gas/publications/EPreports/Shale_Gas_Primer_2009.pdf Description: Document provides technical information and summarizes unconventional natural gas development. |