Colorado's Air Quality Control Commission (AQCC) received a report on Sept. 15 from a 3-year study of oil and gas production air emissions and dispersants along the northern Front Range that was led by Colorado State University (CSU) researchers.
Data from this study, and from a similar one in Garfield County, completed in June, will be used in a health-risk assessment that the state's Department of Public Health and Environment (DPHE), of which the AQCC is a part, expects to complete by Summer 2018.
Information from the two studies represents one of the most comprehensive assessments of air toxics, ozone precursors, and greenhouse gas (GHG) emission rates from oil and gas well operations to date, a DPHE official said.
"These studies will provide us with critical information to design a detailed and accurate health-risk assessment so we can answer questions related to potential health concerns related to oil and gas operations," said Larry Wolk, DPHE's executive director and chief medical officer.
The new study could draw more attention than its predecessor because it examined oil and gas operations' emissions near Colorado's most populous region instead of along the much more rural Western Slope.
DPHE will coordinate the health-risk assessment using the data from this study and is contracting the work to a third party consultant, AQCC said. It is soliciting formal proposals for the assessment and expects to have a contract in place by December.
Jeffrey Collett, a professor and head of CSU's Department of Atmospheric Science, was the North Front Range study's principal investigator, and presented his team's findings at the AQCC's meeting.
The study was designed to characterize and quantify emission rates and dispersion of air toxics, ozone precursors, and GHGs from oil and gas operations in the Denver-Julesburg basin on the northern Front Range.
Focus on three activities
The study aimed to quantify emissions from three specific production activities: hydraulic fracturing, post-fracing liquids flowback, and general production operations. CSU researchers conducted 18 experiments to quantify air emission rates and dispersion of air toxics, ozone precursors, and GHGs from each of the three processes.
Four oil and gas producers-Anadarko Petroleum Co., Encana Corp., Noble Energy Inc., and PDC Energy Inc.-were recruited to participate in the study and provided access to field operations for emission measurement
Overall, production emissions, which may continue for many years, were found to be lower than the shorter-term fracing and flowback emissions, which last for a few days to a few weeks. Emissions in the North Front Range were slightly lower than in Garfield County, but contained heavier-weight organic compounds, likely due to differences in the geology between the basins, DPHE said.
