This article is more than 1 year old

This article is more than 1 year old

A shale gas company’s lorries, police vehicles and protesters’ wood fires have combined to drive up air pollution levels near a gas well in the north of England, despite fracking failing to get started at the site.

Operations at the Kirby Misperton well in North Yorkshire have been delayed after the operator Third Energy ran into financial problems, but the project’s local pollution impact has been revealed by government-backed research.

Alastair Lewis, a professor of atmospheric chemistry at the University of York, said his air quality monitoring project found a group of pollutants had increased in the vicinity of the site to levels normally seen in a city rather than a rural area.

The cause was lorries supplying the well, opposition by campaigners and the resulting police operation.

“The largest, most visible detectable impacts above the surface are on nitrogen oxides (NOx), from the use of compressors, generators and truck movements,” Lewis said.

“And, strangely, in the case of Kirby Misperton, from policing, from [police] vehicles and protest camps. It’s a slightly unusual situation in that the activity of protesting itself is a large source of pollution.”

He said protest tactics such as slow walking in front of lorries supplying the site would have driven up NOx levels, and police vehicles had been a “significant” source of the pollutants.

North Yorkshire police spent more than £600,000 on policing protests at the site over the autumn and winter of 2017-18.

Lewis said monitoring had also detected particulate pollution that he expected had come from the burning of wood by protest camps.

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He said the overall air quality impact of the site had been akin to a single supermarket.

“It kind of shifted a semi-rural location into a chemical environment that looked more similar to a city suburban environment for NOx,” Lewis said, but he added that the levels did not breach regulatory limits. The full research will be published later.

Steve Mason, who lives near the well and campaigns for the Frack Free United group, said he was extremely concerned that air quality had been impacted.

“If the air quality of rural Yorkshire can be turned into that of a city environment by preparatory work for a single well that was never even fracked, imagine the impact if there are thousands of fracking wells strewn across our countryside, which is what the industry is planning to do,” he said.

If the shale gas industry scales up to a national level with 400 wells, NOx levels would increase by up to 4%, according to an earlier government report.