Following the recent seismic events at the Preston New Road site, including a 2.9ML event at 08:30am on 26 August, the OGA has written to Cuadrilla on Friday 30 August requesting extensive data and analysis.
Once provided, this data and analysis will assist the OGA’s full consideration of whether the assumptions and mitigations in Cuadrilla’s PNR 2 Hydraulic Fracture Plan continue to be appropriate to manage the risk of induced seismicity at the Preston New Road site.
Hydraulic fracturing operations will remain suspended until the OGA’s considerations are complete.
Notes:
- 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, nine seismic events (as of 28/08/19) 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.