Research and analysis

Study of ambient air quality at Preston New Road: 23 August 2017 to 11 September 2020: summary

Published 28 November 2022

Applies to England

1. Chief Scientist’s Group report summary

This project examined the results of an ambient air quality monitoring campaign that was carried out over 3 years by the Environment Agency’s Ambient Air Monitoring team near a well pad exploring for shale gas at Preston New Road, Little Plumpton, Lancashire. The monitoring site was in the nearest residential community, and the results provided information about the well pad’s potential impact on air quality to reassure residents that air quality in the community was being routinely monitored and assessed.

1.1 Background

Construction of the well pad started in January 2017. Two periods of hydraulic fracturing and gas extraction took place: one at well 1 between 15 October and 17 December 2018, and one at well 2 between 15 and 26 August 2019. A moratorium on hydraulic fracturing was introduced in England on 2 November 2019, which suspended further hydraulic fracturing activities.

1.2 Approach

The mobile monitoring facility was placed about 400 m west-south-west of the well pad. Monitoring was carried out between 23 August 2017 and 11 September 2020 – a total of 1,116 days. The pollutants monitored included particulate matter (PM10 & PM2.5); oxides of nitrogen (NO and NO2); methane (CH4); and benzene, toluene, ethylbenzene, and m&p- xylene (BTEX). These pollutants were selected as they could be emitted during gas extraction and related activities at the well pad.

1.3 Results

The pollutant monitoring data was analysed using time series plots and compared with air quality standards and a daily Air Quality Index. The data was also analysed to identify how pollutant levels varied with wind direction, wind speed, and time-of-day.

A detailed statistical analysis of the well pad impacts at the monitoring site was not possible for 2 reasons. Firstly, because winds from the well pad to the site were very infrequent. Secondly, because the A583 road lay in the same direction from the site as the well pad, so that any impacts from the well pad were combined with impacts from road traffic and were generally too small to be distinguishable from those impacts. Although the data did not allow a detailed statistical assessment of well pad impacts, pollutant time series and directional plots were inspected for any prominent signals that might be associated with the well pad.

1.4 Conclusions

The monitoring results indicated that ambient pollutant concentrations at the monitoring site complied with ambient air quality standards, and that there were no substantially elevated concentrations from the direction of the well site during periods of hydraulic fracturing.

1.5 Project details

This summary relates to information from the following project:

  • Report: SC190008/R
  • Title: Study of ambient air quality monitoring at Preston New Road
  • Project manager: Roger Timmis, Chief Scientist’s Group

This project was commissioned by the Environment Agency’s Chief Scientist’s Group, which provides scientific knowledge, tools and techniques to enable us to protect and manage the environment as effectively as possible.

Enquiries: [email protected].

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