Jeff Collett Department of Atmospheric Science Colorado State University

Jeff Collett Department of Atmospheric Science Colorado State University

People CSU Atmos Sci: Arsineh Hecobian, Tony Prenni, Yi Li, Andrea Clements, Ashley Evanoski, Jeff Pierce, Brad Wells, Kira Shonkwiler, Landan MacDonald, Florian Schwandner, Suresh Raja CSU Soil and Crop Science: Jay Ham NPS/CIRA: Bret Schichtel, Jenny Hand, Derek Day, Bill Malm ARS: Mark Tigges, Stephen Holcomb, Cassie Archuleta, Lincoln Sherman, Bryan Bibeau Shell: Jim Sewell, Angela Zivkovich Funding Garfield County CDPHE National Park Service Shell, Encana, WPX Energy, Bill Barrett Corp., Ursa Resources

While natural gas offers a cleaner-burning alternative to combustion of other fossil fuels, air emissions are associated with its production and distribution Criteria Pollutants O 3 (VOC + NO x + sunlight) PM 2.5 Hazardous Air Pollutants / Air toxics Diesel particulate matter Benzene, toluene, ethylbenzene, xylenes Climate CH 4 Black carbon Source: U.S. Energy Information Administration (EIA)

Characterization of source specific air toxics, ozone precursors, and CH 4 emissions and their near-field dispersion Garfield County, CO North Front Range Local-to-regional scale impacts on air quality, including PM formation and haze Boulder, WY Bakken, ND W. Malm

Garfield County Study (2012-2015) Front Range Study (2013-2016) Source: COGCC Source: http://pubs.usgs.gov/dds/dds-069/dds-069-p/reports/69_p_ch_2.pdf

Characterize emissions and downwind dispersion of air toxics (e.g., benzene, toluene, ethylbenzene and xylenes (BTEX) ozone precursors (VOCs and NO x ) methane Cooperate with industry to gain full site access activity information Focus on new wells in Garfield County new wells and production emissions(front Range)

Preparation of Well Pad Well Drilling Hydraulic Fracturing Flowback Well Completion Objectives Quantify emissions of chemical compounds (air toxics, ozone precursors, NO x, and methane) during new well development Characterize how these compounds are dispersed in the atmosphere downwind of the site Produce a peer-reviewed, public dataset of high quality emissions data Source of Figures: http://lingo.cast.uark.edu/lingopublic/natgas/wellprep/index.htm

Study team Colorado State University Jeff Collett, PI Jay Ham, co-pi Air Resource Specialists, Inc. Technical Advisory Committee Representatives from industry, CDPHE, USEPA, NCAR, BLM Operations Committee Sponsors Garfield County Encana, WPX Energy, Bill Barrett Corp., and Ursa Resources

Emissions determined using tracer ratio method Combination of time-integrated and continuous measurements to observe temporal and spatial variability Mobile and fixed sampling platforms

Mobile 4WD Plume Tracker C 2 H 2 CH 4 Met GPS CSU Mobile Lab VOCs NO X CO WD & WS data Integrated Measurements VOCs C 2 H 2 Meteorological Measurements Temp. RH Wind Direction Wind Speed

Tracer (acetylene) released at a known rate Must co-locate with source Measurements Real Time: Cavity Ring Down Spectroscopy Acetylene and Methane Offline: Canister VOC/tracer ratio at each point provides an independent emission estimate

Multiple models to be used System for Atmospheric Modeling (research model) AERMOD (regulatory model) Use measured emissions and meteorology to model concentration field downwind Compare against field measurements to test model accuracy

Several field deployments completed at multiple locations More field work, data analysis, and modeling in 2014/15 Peer-reviewed findings will be released and available to use in subsequent health impact assessments, regional air quality assessments, etc. Study emphasis is on Emissions for drilling, fracking, and flowback Downwind plume dispersion and concentrations Air toxics, ozone precursors, and methane

CSU under contract with State of Colorado Technical advisory panel finalizing study scope and measurement priorities Study methods similar to Garfield County study Study scope will include new wells and production emissions Field measurements to begin in spring 2014 with study completion in late 2016 Industry cooperators and additional funding being sought

Nitric acid production NO + O 3 NO 2 + O 2 NO 2 + OH HNO 3 Ammonium nitrate production NH 3(g) + HNO 3(g) <=> NH 4 NO 3(p) Particles favored at low T, high RH Ammonium nitrate particles ~200-600 nm Several days atmospheric lifetime Important cause of haze Natl. Parks Conservation Assn.

Long-term measurements of the NH x -NO x - SO x system in Boulder, WY CSU, Air Resource Specialists, Shell

Con 0.5 0.5 0.0 0.0 2.5 (e) SO 4 2-0.25 (f) K + Concentration ( µg/m 3 ) 2.0 1.5 1.0 0.5 0.20 0.15 0.10 0.05 0.0 0.00 Concentration ( µgn/m 3 ) 2.0 1.5 1.0 0.5 (g) NH 3 (g) N(-III) + NH 4+ (p) 1.2 1.0 0.8 0.6 0.4 0.2 (h) N(+V) HNO 3 (g) + NO 3- (p) 0.0 0.0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Li et al., Atmos. Env., 2013 Ammonia shows typical summer max Nitric acid/nitrate shows unusual winter max tied to winter photochemical smog

Li et al., Atmos. Env., 2013 2007 2008 2009 2010 2011 3.0 (a) HNO 3 (g) NO 3 - (p) 2.0 1.0 Concentration (µg/m 3 ) 0.0 1.6 1.2 0.8 0.4 0.0 2.0 1.5 1.0 0.5 0.0 (b) NH 3 (g) (c) SO 4 2- NH 4 + (p) K + 1/1/07 7/1/07 1/1/08 7/1/08 1/1/09 7/1/09 1/1/10 7/1/10 1/1/11 7/1/11 1/1/12 Date Winter fine particle nitrate formation limited by ammonia availability Annual average NH 3 mixing ratio = 0.30 ppbv 0.20 0.15 0.10 0.05 0.00 K + Concentration (µg/m 3 )

Oil Production in North Dakota https://www.dmr.nd.gov/oilgas/

From Jenny Hand, NPS/CIRA

Bakken Fine Particle Concentrations Concentration (µg m -3 ) Nitrite Chloride Sodium Potassium Magnesium Calcium Ammonium Nitrate Sulfate 20 Theodore Roosevelt North Unit (THRO-N) 15 10 Episode 1 Episode 2 5 0 20 Fort Union (FOUN) 15 10 5 0 20 Knife River (KNRI) 15 10 5 0 20 15 10 5 0 Medicine Lake (MELA) Sampling Date

PM Precursor Gas Concentrations: All Sites 5 Sulfur Dioxide Nitric Acid Ammonia Theodore Roosevelt North Unit (THRO-N) Concentration (µg m -3 ) 0 5 Fort Union (FOUN) 0 5 Knife River (KNRI) 0 5 Medicine Lake (MELA) 0 Sampling Date

1 2 Ammonia nearly depleted in Theodore Roosevelt North during episode 1, but not episode 2 Excess ammonia always available at Fort Union HNO 3 currently limits NH 4 NO 3 formation

Work underway to measure emissions of air toxics, ozone precursors, and methane in Colorado Emissions quantified for individual processes Air toxics, ozone precursors, and methane With operator information about activity during emissions measurement Complementary to other top-down emission estimates CSU work in WY and ND focused on oil and gas impacts on fine particle and haze formation NO x controls in Wyoming and limited ammonia prevent large fine particle/haze episodes Bakken pilot study observed sufficient ammonia to permit substantial NH 4 NO 3 formation Increased NO x emissions could increase PM and haze formation