The Scottish Environment Protection Agency (Sepa) is to seek prosecution over unscheduled flaring at Mossmorran in Fife.
A report will be submitted to the Crown Office over unplanned flaring over a seven-day period in April 2019.
More than 900 complaints were made during the unplanned flaring – the highest number Sepa has ever received over a single event.
This came after a final warning letter in 2018 to ExxonMobil for “preventable and unacceptable” flaring in 2017.
Terry A’Hearn, chief executive of Sepa, said: “Compliance with Scotland’s environmental laws is simply non-negotiable.
“Over a number of years, communities across Fife have repeatedly endured unplanned flaring. Whilst flaring is an important safety mechanism of such facilities, it must become the exception, rather than routine.
“People rightly expect that their lives won’t be impacted by nearby industrial processes and yet again, over an extended period during Easter 2019, communities were impacted by unacceptable and preventable flaring.
“Consequently, following an extensive investigation into the flaring at Mossmorran during April 2019, we intend to shortly submit a report to the Crown Office and Procurator Fiscal Service for consideration of prosecution.
“It’s right that we take enforcement action for the Easter 2019 flaring event. What is just as important is that ExxonMobil Chemical Limited address the root-causes of ‘unacceptable flaring’.”
The plant was shut down last year to allow for essential maintenance work, with ExxonMobil saying it had invested more than £140m of upgrades to the plant.
ExxonMobil has been contacted for comment.
Scottish Greens environment spokesperson and Fife MSP Mark Ruskell said: “This is a very welcome and unprecedented intervention by Sepa.
“The agency said it received more complaints over this flaring incident than any other environmental event in history, which reflects the level of suffering felt by those who have had to live in the shadow of this fossil fuel relic for years.
“I also heard from so many constituents during this time, families who endured six days of hell and more since, so I’m relieved that their voices have been heard and action taken.
“If we are serious about the health and wellbeing of our communities, we need this kind of rigour from our environmental watchdog.”
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