The fracking company, Cuadrilla, has breached rules on monitoring the flare at its Preston New Road shale gas site in Lancashire.
The breach happened in autumn 2019 during nitrogen lifting – a technique used to clear waste from a well and increase the flow of gas.
The operation had just been approved, despite opposition from local people, at the time of the breach.
This is the latest in a series of low-level failures by Cuadrilla to comply with the environmental permit at its site near Blackpool.
In September 2019, the company received its third formal warning from the Environment Agency (EA) in just over a year. It had failed to monitor key substances in groundwater and failed to tell the EA about missing data. It was also accused of poor communication and supervision of the company carrying out the monitoring.
In December 2019, the EA said Cuadrilla had breached a condition on methane monitoring. The company had not told the EA about the deployment of a methane monitor and the data was not reviewed for abnormal results within 48 hours of the end of the monitoring period.
DrillOrDrop has also reported on breaches on waste management, unauthorised methane venting and incorrectly certified equipment. In 2017, Spinwatch reported on at least five permit breaches in seven months, most concerning surface water.
Video records overwritten
In the latest breach, Cuadrilla overwrote video footage from the flare stack when the records should have been kept.
The EA said CCTV was installed to monitor the flare on 24 October 2019 at the start of the nitrogen lift on the site’s second well, known as PNR2.
Video viewed by the EA on 31 October showed the flare were burning cleanly and there were no visible smoke or flames.
But the EA said:
“The CCTV system was setup to overwrite the footage every seven days and therefore we did not view the footage from 24 October.”
There had been several local complaints around that time about flames and smoke from the flares.
The EA said:
“Whilst we understand that there was no environmental impact, it is a requirement that monitoring records must be retained.”
The breach was classed as a category 4 non-compliance, the least serious with no impact on human health, quality of life or the environment.
A spokesperson for Preston New Road Action Group, which campaigned against Cuadrilla’s operations, said:
“At the time that Cuadrilla were flaring Well 2 much concern was raised by local residents about the amount of black smoke and visible flames that were seen coming from the flare stacks, as we had been assured that no flames would be visible.
“It seems rather coincidental that data that would have helped to evidence exactly what happened has now been lost due to this breach.”
The EA compliance report on the breach also recorded that Cuadrilla had vented a total of 155kg of methane from the Preston New Road well by the time the nitrogen lift ended on 11 November.
This was described by the EA as “considerably less” than the worst case in the company’s air quality assessment.
The report also recorded that levels of methane at the site boundary on 27 October 2019 were higher than the notification threshold. A total mass of 37kg of methane was released that day, the EA said.
Under changes to the environmental permit granted in October 2019, Cuadrilla was allowed to release unburnt methane during nitrogen lifting.
Allowing the change, the EA accepted:
“The use of nitrogen, which is an inert gas, may result in the release of uncombusted formation natural gas (which is principally methane), known as venting.”
Opponents of the technique were concerned about the climate-damaging effect of releasing methane, a potent greenhouse gas, and the health impacts of emissions of other gases, such as benzene.
On 27 October 2019, the level of volatile organic compounds at Preston New Road was measured at 0ppm (parts per million), the EA said.
Since this incident, the EA said Cuadrilla decided to add propane to the flare as a support fuel at lower concentrations of methane. A cost-benefit analysis had determined that propane should be used at 20% methane concentration. But Cuadrilla had opted to add support fuel at 13% methane, the EA said.