HARC deployed a mobile laboratory equipped with a Geographical Positioning System (GPS) and a Proton Transfer Reaction-Mass Spectrometer (PTR-MS) to perform real time measurements of ambient concentrations of toxic volatile organic compounds in the vicinity of oil and gas sites located on a large private property in the Eagle Ford Shale of South Texas.
Potential Near-Source Ozone Impacts of Oil and Gas Sites in the Eagle Ford Shale
With financial support from the Environmental Defense Fund, Dr. Eduardo (Jay) Olaguer used the HARC microscale air quality model to assess the ozone impacts of oil and gas production facilities in the Eagle Ford Shale. Different geographical configurations and ozone transport conditions were used to gauge how much oil and gas sites may increase ambient ozone over regional background levels. A unique aspect of the assessment was the application of the model inverse mode and automated gas chromatograph measurements to determine the composition of suspected flare event emissions. Primary formaldehyde (HCHO) and reactive hydrocarbons from combustion sources were found to increase peak ambient ozone within the study area in Karnes County, Texas by up to ~4 ppb. Moreover, flare event emissions increased exports of odd oxygen (O3 + NO2) at the model edge by up to ~12 ppb. Carcinogenic species were also significantly enhanced; HCHO concentrations over 10 ppb and benzene concentrations over 50 ppb were produced within 10 km and 500 m respectively downwind of the flare event source.