Question to the Department for Business, Energy and Industrial Strategy:

To ask the Secretary of State for Business, Energy and Industrial Strategy, with reference to the traffic light monitoring system for regulating fracking-induced seismicity, for what reasons red events are allowed as part of an operator’s hydraulic fracturing plan.

Under the Traffic Light System (TLS), regulated by the Oil and Gas Authority (OGA), if a seismic event of magnitude 0.5 or above is detected (a “red event”), injection must be paused and pressure in the well be reduced, followed by monitoring for a minimum of 18 hours to determine the cause of the seismic event. This precautionary threshold is set at a level well below what could be felt at the surface.

This threshold and pause in operations allows the OGA to review the event to ensure it is in line with the geological understanding set out in the Hydraulic Fracture Plan (HFP), which must be agreed with regulators before operations can commence, and that the risk of induced seismicity is being appropriately managed by the operator.