Approaches to baseline and operational fixed-site methane monitoring

With growing concerns regarding climate change in the scientific, political and public spheres, there is mounting pressure on businesses to provide accountability for their impacts on the environment. The recently published IPCC report highlighted reductions in methane emissions as a central factor in keeping global warming below the critical threshold of 1.5 oC above pre-industrial temperatures. Hence, industrial activities associated with fugitive emissions of methane may well be under increased scrutiny from both the government and the public in the future. To quantitatively assess the extent of fugitive emissions from an industrial practice, be it conventional or unconventional shale gas extraction, it is necessary to constrain the baseline environmental parameters prior to any operational activity.

We present a method for rigorous statistical and climatological assessment of existing environmental conditions, with a focus on greenhouse gas measurements, for the development of a set of baseline criteria against which any operational emissions could be compared in the context of fugitive methane leak detection and quantification. We outline the logic behind baseline site design, accounting for the prevailing wind direction and existing localised sources of pollution. We also describe the equipment setup and calibration and data analysis procedures through assessment of our own baselining work conducted over the past few years at two hydraulic fracturing sites in northern England. Finally, we demonstrate how our observations of the baseline were interpreted to provide thorough controls against which future emissions at either site may be evaluated.