Impacts of Oil and Gas Development in the North Dakota Bakken Formation Region on Winter Particulate Matter and Associated Precursor Gases

Due to the development of hydraulic fracturing and horizontal drilling, oil and natural gas production has rapidly increased in recent years in the United States. The impacts on air quality from these drilling activities are relatively unknown, especially in recently developed locations such as the Bakken Formation region in North Dakota. An initial air quality study was conducted between February and April 2013 in national parks within the area of the most intensive oil and natural gas operations in this region. Measurements of particle chemistry, ozone and precursor gases such as nitrogen oxides were obtained in Theodore Roosevelt National Park, Fort Union Trading Post National Historic Site and Medicine Lake National Wildlife Refuge. Several episodes with high ammonium nitrate and ammonium sulfate particle concentrations concurrent with elevated concentrations of nitrogen oxide gases were observed, mainly during periods of stagnation. Elevated concentrations of sulfur dioxide were also detected. This prompted a second intensive field campaign conducted between November 2013 and March 2014 which also included measurements of volatile organic compounds (VOC). Fewer high particle episodes were observed during this second study but elevated concentrations of SO2 were still measured. Measurements of VOC source signatures of oil and gas operations indicated significant contributions from the oil and gas activities. The high time resolution particle characterization and precursor gas concentrations, as well as the VOC measurements and meteorological data will be used to investigate the sources and transport patterns of emissions from oil and natural gas drilling operations and how they impact the national parks in this region.