Hydraulic fracturing at Preston New Road: update
Hydraulic fracturing operations at the Preston New Road site are currently paused following a seismic event.
The event was recorded at 23:01 yesterday (24 August) with a magnitude 2.1ML and is the largest to date. As this event exceeded the magnitude 0.5 threshold in the “traffic light system”, the operator has suspended injection activities, reduced well pressure and is continuing to monitor seismicity during this pause.
During pauses, the OGA compares the location, magnitude and ground motion of these seismic events against the operator’s agreed Hydraulic Fracture Plan (HFP).
OGA Director of Regulation, Tom Wheeler, said: “Our regulatory regime is deliberately cautious with strict controls in place to manage and monitor seismicity. This is the largest seismic event triggered by the current operations at Preston New Road to date and it may have been felt by some people close to the site. This pause in operations allows us to review the event, checking whether it is in line with the geological understanding set out in the operator’s HFP and that the risk of induced seismicity is being appropriately managed."
Notes to editors
- A graphic/image describing the traffic light system can be found here.
- For more information on HFPs and the OGA’s traffic light system for monitoring operations, click here.
- A Hydraulic Fracture Plan (HFP) sets out the steps that the operator will take to minimise seismic risks and the ways in which the operator will monitor and control the hydraulic fracturing process. The HFP must be approved independently both by the OGA and by the Environment Agency (EA), with the Health and Safety Executive (HSE) having had the opportunity to comment.
- The OGA requires detailed geological studies to be undertaken by an operator to assess the risk of seismic activity, and to prevent any hydraulic fracturing operations taking place near identified geological faults. The OGA must also be satisfied that controls are in place to minimise the risk of a seismic event or any disturbance to those living and working nearby.
- To date, six seismic events have exceeded the magnitude 0.5ML threshold during Preston New Road Well 2 operations.
- In total six seismic events exceeded the magnitude 0.5ML threshold during Preston New Road well 1Z operations in late 2018.