Skip to main content

SEPA’s regulatory pathway to reduce impacts of flaring at Mossmorran

Date published: 13 July 2023

Enforcement operations

A series of regulatory requirements, aimed at reducing the impact of flaring at the Mossmorran Complex on surrounding communities in Fife, has been implemented.

The Complex is home to industrial facilities including the ExxonMobil Chemical Limited Fife Ethylene Plant and Shell UK Limited. Both companies generate gases as part of their operations and, in certain situations, release excess gas through controlled burning known as flaring.

In 2018, the Scottish Environment Protection Agency (SEPA) set out to ensure flaring became an exception rather than routine following concerns from local residents about the frequency, intensity and potential impacts.

Regulatory action

SEPA are clear that compliance with Scotland’s environmental laws is non-negotiable.

In April 2019, SEPA announced a formal investigation into a seven-day period of flaring from the ExxonMobil Chemical Limited site in Fife. A report was submitted to the Crown Office and Procurator Fiscal Service for consideration of prosecution. Upon receipt of the report, COPFS become responsible for the assessment and progression of the case.

A programme of required investment and improvements at Mossmorran was set out by SEPA to tackle further episodes of flaring.

This led to a £140m upgrade at the ExxonMobil Chemical Limited Fife Ethylene Plant, including the installation of a noise reducing elevated flare tip in spring 2021 and a new enclosed ground flare brought into operation in June 2023. Shell UK Limited also installed a noise reducing flare tip in August 2022 and is committed to completing the installation of its enclosed ground flare by 2025 as part of its wider improvement works.

To further strengthen the regulation and monitoring of both sites, SEPA also asked the Irish Environmental Protection Agency (IEPA) to carry out a peer review in May 2020, detailing actions and good practice to drive compliance at Mossmorran. SEPA’s final response to this review has now been published. Nine of the recommendations were already underway by SEPA and a further eight were taken forward, one of which was considered and two were rejected as not being suitable in this instance. The recommendations have helped SEPA take forward regulatory work in relation to the Mossmorran Complex.

Commitment to communities

SEPA have heard first-hand from local residents, the constituency MP, MSPs and Councillors about the impacts they had experienced as a result of flaring at Mossmorran.

Chris Dailly, Head of Environmental Performance - Geographic at SEPA, said:

“Communities across Fife have the right to a future where flaring is the exception rather than routine. Through our continued commitment to ensuring compliance and the significant investment by site operators, we hope residents are now seeing the results of the work we began in 2018.

“We’ve used the full force of our powers, from regulatory requirements and operating permit variations to Final Warning Letters and submission of a report to the Crown Office for consideration of prosecution. We’ve listened to those who live and work in the area, through in-person and online engagement sessions, and heard about the impacts flaring was having on people of all ages. We’ve done our best to redesign our communications, our air quality monitoring and how we make information available, to better meet the needs of the communities around the Mossmorran Complex.”

Next steps

SEPA have been monitoring air quality in community locations surrounding the Mossmorran complex since early 2019 and this work will continue. While no breaches of air quality objectives have been recorded, the number of potential pollutants measured, and the geographic coverage of the air quality network have been increased. The new air quality monitoring network, designed with the support of local communities, is live allowing air quality data to be viewed in close to real time.

Over the coming months, SEPA will be carrying out a full audit of the new ground flaring system at ExxonMobil and closely monitoring compliance, while also ensuring progress with Shell UK’s improvements and maintenance.

Work will continue with partner organisations including Fife Council, NHS Fife and the Health and Safety Executive (HSE), and local communities to share information. Updates will continue to be published on SEPA’s refreshed online community information hub and provided to the Mossmorran and Braefoot Bay Safety Liaison Committee.

Notes to editors

SEPA’s final response to the Mossmorran Best Practice Review is published on our website.


  • April 2018
    • Final Warning Letters served to both ExxonMobil Chemical Limited and Shell UK Limited by SEPA regarding flaring.
  • June 2018
    • Notices of variations to Permits were served on ExxonMobil Chemical Limited and Shell UK Limited, which included the requirement to complete an evaluation of the Best Available Techniques (BAT) to prevent and, where that is not possible, reduce emissions of noise, vibration and smoke associated with flaring.
  • January-April 2019
    • SEPA undertakes air quality monitoring.
  • April 2019 
    • SEPA receives the Best Available Techniques (BAT) assessments from Shell UK Limited and ExxonMobil Chemical Limited.  
    • ExxonMobil Chemical Limited commits to the installation of a fully enclosed ground flare.  
  • August 2019
    • Operating permit variations served on ExxonMobil Chemical Limited and Shell UK Limited to require both operators to achieve ‘Best Available Techniques’ at Mossmorran.  
    • ExxonMobil Chemical Limited and Shell UK Limited each submitted environmental monitoring programmes.  
    • SEPA deploys monitoring network at three locations around the site and commences regular publication of reports, concluding no significant impacts on local air quality.  
  • July 2020
    • Submission of report to the Crown Office for consideration of prosecution in relation to the flaring at the Mossmorran complex during April 2019.  
  • April 2021
    • £140m ExxonMobil Chemical Limited investment programme begins, including installation of a noise reducing elevated flare tip.  
  • June 2022
    • SEPA varies Shell UK Limited’s Fife Natural Gas Liquids Plant (Shell FNGL) permit requiring a detailed project plan for a totally enclosed ground flare system to be provided to SEPA by 31 January 2023 and for the new ground flare system to be operational by 31 December 2025.  
  • August 2022
    • Shell FNGL install a new noise reducing elevated flare tip. 
  • January 2023
    • Project plan for a totally enclosed ground flare system to be installed at Shell FNGL by the end of 2025 received.  
  • June 2023
    • ExxonMobil fully enclosed ground flare announced as fully operational.