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Richard Webb
A total of £140m is to be spent reducing flaring and improving the reliability of a Fife chemical plant.
ExxonMobil said it has started recruiting 850 temporary workers over the next 12 months to carry out the work.
The operator said the investment was on top of the £20m it spends annually on maintaining its Mossmorran site.
Residents have complained of light pollution and noise often disrupting their sleep during flaring events.
ExxonMobil said the work - which includes fitting flaring tips and other technology to reduce flaring - would be complete by September 2020.
Currently Exxonmobil is temporarily shut down while two of its three boilers have parts renewed and repaired.
The company said it expected to resume operations during the fourth quarter of the year - between October and December - after shutting on 12 August.
The work will involve building a flare on ground level which will replace an elevated flare at the site, reducing the visual impact of the plant.
In addition, the works will lead a reduction in the amount of vibration felt by local residents, plant bosses claim.
Plant manager Jacob McAlister said: "The reliability of the plant has not been where we want it to be and we recognise that. £140m is a major step and shows our commitment that we are addressing these issues.
"We built this [elevated flare tower] 34 years ago to keep the community safe and it is doing its job but we have more advanced technology now that we didn't have when it was built which we hope will address the issues we have been having."
He added: "We're intent on making improvements, which will drastically reduce flaring and the duration of elevated flaring. I hope in one year from now a significant portion of this project will be in place and that the number of flaring events will be driven down.
He added: "We are not spending this money to pacify the community, we are concerned about how the plant is impacting on their lives and we are announcing how we are addressing that."
Unburnt fuel
Meanwhile, BBC Scotland has learned the plant has been issued with an improvement notice over the risk of an explosion.
The Health and Safety Executive (HSE) said ExxonMobil had failed to take all measures necessary to reduce the risk of "firebox explosion from furnaces".
The firebox is an area in the plant's furnaces where fuel is burnt.
Inspectors said the risk came from an uncontrolled accumulation of unburnt fuel in the firebox.
The HSE notice, which affects seven furnaces at the plant, states "the measures currently in place are not sufficient to reduce the risk to as low as reasonably practicable".
It was issued in July and ExxonMobil has until March next year to comply with the improvement order.
In August it emerged that Scotland's environmental regulator Sepa had received almost 1,400 complaints about the Mossmorran site, which is also shared by Shell Fife NGL.