Tesco has been fined a massive £8m after admitting polluting the River Irwell with thousands of litres of petrol.
The incident, which occurred in July 2014, saw a major leak from a filling tank at a store in Haslingden.
More than 40 dead fish, including brown trout, were found within 1.5 miles of where the pollution entered the water and anglers reported dead fish in Bury, more than six miles downstream.
It sparked a huge clean-up operation involving the Environment Agency, Lancashire County Council, United Utilities, Lancashire Fire and Rescue Service and Lancashire Police.
Residents were also forced to leave their homes due to petrol odours coming from the sewer network.
An Environment Agency investigation found that the incident resulted from Tesco’s failure to address problems with part of the fuel delivery system and an inadequate alarm system.
It was also compounded by poor emergency procedures.
On Thursday at Preston Crown Court the supermarket giant was fined a total of £8m - £5m for a health and safety offence and £3m for an environmental offence.
Tesco earlier pleaded guilty to the offences.
The court heard about 23,500 litres of unleaded petrol leaked from the tank over a 29 hour period. Around 7,000 litres was later recovered at the site and the remainder escaped into the sewer system and watercourse.
Mark Easedale, from the Environment Agency, said:
County Councillor Albert Atkinson, deputy leader of Lancashire County Council, which carried out the investigation with the EA, added:
- Tesco have been approached for comment.