Predictions of the Impacts of Future Marcellus Shale Natural Gas Development on Regional Ozone

Recent discovery of shale gas reserves, combined with advances in drilling and fracturing technology, are leading to extensive development of natural gas in the Marcellus Shale formation which underlies parts of Pennsylvania, West Virginia, Ohio and New York. To assess the impacts of this development on regional air quality, we have constructed a VOC, NOx and PM2.5 emissions inventory for the development and production of gas from the Marcellus formation. In 2020, we estimate that Marcellus activities will contribute about 12% to both regional NOx and VOC emissions. These numbers were obtained as a best estimate (mean) from a distribution obtained through several Monte Carlo runs. We speciated these emissions for use in a 3-D chemical transport model (PMCAMx) to simulate their effects on regional ozone. The projected Marcellus emissions for 2020 were added to a 2007 base inventory developed from the NEI. We have performed multiple simulations to investigate the effects of Marcellus development on regional air quality. The model predicts significant ozone changes in the Marcellus region with a uniform increase of few ppb across a wide region of the Northeast. Sensitivity studies are being performed to investigate the effects of emissions controls and sensitivity to VOC and NOx emissions.