Establishing an air pollution baseline before shale gas extraction

Unconventional gas extraction has become a major component of the energy sector in the US, however the development of the industry in Europe has been limited, largely limited due to concerns over environmental impacts. One of the most frequently cited public concerns in Europe has been a potential reduction in air quality, through both direct onsite emissions of methane, volatile organic compounds (VOCs) and NOx, and more distributed emissions arising from the supply chain and vehicle movements. Within the UK potential future shale gas impacts from individual sites are to be evaluated against an observational environmental baseline. In some cases this has required new measurements to be established in rural locations that do not currently need measurements to be compliant with the EC Air Quality Directives. 

This presentation describes how an environmental baseline climatology of air pollution has been established over two years at potential UK shale gas drilling sites in Kirby Misperton (North Yorkshire) and Little Plumpton (Lancashire). This work forms part of a larger environmental baseline study sponsored by the UK Department of Energy and Industrial Strategy and coordinated by the British Geological Survey. Continuous high-resolution air pollution observations have been made at each site and a number of data analysis tools developed. These have established the spatial distribution and variability in key direct emissions such as NOx, particulate matter, non-methane hydrocarbon and greenhouse gases and secondary pollutants including ozone. The baseline assessments have generated seasonal climatologies of each air pollutant as a function of wind speed and direction and given indications of the relative contributions from local point sources and the wider regional background. The environmental baseline observations at both candidate shale gas sites show that the concept of an environmental baseline is complex to define and that new shale gas industries will potentially operate in rural and semi-rural locations that already have surprisingly complex pollution signatures and sources, including existing oil and gas activities, agriculture and road transport. The sensitivity of the reanalysis methods to identify new local sources of pollution will be demonstrated. The wider impacts of possible future cumulative impacts on the air pollution climate of the North of England (should shale gas extraction expand) will also be discussed. In particular the likely sensitivity of the region to increases in tropospheric ozone arising from elevated rural NOx and VOCs from shale industries will be quantified.