Influence of oil and gas field operations on spatial and temporal distributions of atmospheric non-methane hydrocarbons and their effect on ozone formation in winter

Abstract

Abstract. Emissions from oil and natural gas development during winter in the Upper Green River basin of Wyoming are known to drive episodic ozone (O3) production. Contrasting O3 distributions were observed in the winters of 2011 and 2012, with numerous episodes (hourly O3 ≥ 85 ppbv) in 2011 compared to none in 2012. The lack of O3 episodes in 2012 coincided with a reduction in measured ambient levels of total non-methane hydrocarbons (NMHC). Measurements of speciated NMHC, and other air quality parameters, were performed to better understand emission sources and to determine which compounds are most active in promoting O3 formation. Positive matrix factorization (PMF) analyses of the data were carried out to help achieve these goals. PMF analyses revealed three contributing factors that were identified with different emission source types: factor 1, combustion/traffic; factor 2, fugitive natural gas; and factor 3, fugitive condensate. Compositional signatures of the three contributing factors were identified through comparison with independently derived emission source profiles. Fugitive emissions of natural gas and of condensate were the two principal emission source types for NMHC. A water treatment and recycling facility was found to be a significant source of NMHC that are abundant in condensate, in particular toluene and m+p-xylene. Emissions from water treatment have an influence upon peak O3 mixing ratios at downwind measurement sites.

Sources and characteristics of summertime organic aerosol in the Colorado Front Range: perspective from measurements and WRF-Chem modeling

“…In recent decades, stricter regulations by the U.S. Environmental Protection Agency and state agencies have resulted in lower emissions of black carbon, hydrocarbons (including air toxics), and nitrogen oxides in many urban environments (e.g., Parrish et al, 2002;Peischl et al, 2010;Sather and Cavender, 2012;Warneke et al, 2012;Zhou et al, 2014;Kirchstetter et al, 2017) while in other areas, both populated and remote, expansion or emergence of new oil and natural gas (O&G) exploration and production activities has led to higher emissions of air toxics, methane, and non-methane hydrocarbons, e.g., C 2 − C 8 and larger alkanes, benzene, and larger aromatic species (e.g., Petron et al, 2012;Adgate et al, 2014;Helmig et al, 2014;Pekney et al, 2014;Warneke et al, 2014;Field et al, 2015;Koss et al, 2015;Rutter et al, 2015;Swarthout et al, 2015;Helmig et al, 2016;Prenni et al, 2016;Abeleira et al, 2017;Koss et al, 2017). The impact of higher emissions of such hydrocarbons from oil and gas fields of Utah and Wyoming on wintertime ozone has been assessed through recent measurement and modeling studies (Carter and Seinfeld, 2012;Rappenglück et al, 2014;Ahmadov et al, 2015).…”

Sources and Characteristics of Summertime Organic Aerosol in the Colorado Front Range: Perspective from Measurements and WRF-Chem Modeling

“…In recent decades, stricter regulations by the U.S. Environmental Protection Agency and state agencies have 20 resulted in lower emissions of black carbon, hydrocarbons (including air toxics), and nitrogen oxides in many urban environments (e.g., Parrish et al, 2002;Peischl et al, 2010;Sather and Cavender 2012;Warneke et al, 2012;Zhou et al, 2014;Kirchstetter et al, 2017) while in other areas, both populated and remote, expansion or emergence of new oil and natural gas (O&G) exploration and production activities has led to higher emissions of air toxics, methane, and non-methane hydrocarbons, e.g., C 2 -C 8 and larger alkanes, benzene and larger aromatic species (e.g., 25 Petron et al, 2012;Gilman et al, 2013;Adgate et al, 2014;Helmig et al, 2014;Pekney et al, 2014;Warneke et al, 2014;Field et al, 2015;Koss et al, 2015;Rutter et al, 2015;Swarthout et al, 2015;Helmig et al, 2016;Prenni et al, 2016;Abeleira et al, 2017;Koss et al, 2017). The impact of higher emissions of such hydrocarbons from oil and gas fields of Utah and Wyoming on wintertime ozone has been assessed through recent measurement and modeling studies (Carter and Seinfeld 2012;Edwards et al, 2014;Rappenglück et al, 2014;Ahmadov et al, 2015).…”

Diffusive sampling of air pollutants in US basins with oil and gas development

“…Field et al. [23] reported extremely high concentrations of BTEX downwind of a water treatment and recycling facility, and noted the significance for wintertime ozone formation. High BTEX was also reported by Field et al [22] at an area of the Pinedale Anticline known as the Mesa.…”