Tesco has been prosecuted for leaking 23,500 litres of petrol into the sewerage system and local rivers in Lancashire.
The incident, in July 2014, led to residents having to seek medical help after petrol odours coming from the sewer network gave them headaches and nausea. The smell affected residents up to 1km away.
Some of the petrol also entered Langwood Brook and the River Irwell. More than 40 dead fish were found within 2.5 kilometres of where the pollution entered the watercourse, and anglers reported dead fish more than ten kilometres downstream.
The leak was caused by Tesco’s failure to address a known issue with part of the fuel delivery system and an inadequate alarm system at a petrol station operated by the retailer in Haslingden, north of Manchester, according to the Environment Agency. The supermarket’s emergency procedures were also found to be poor, the regulator said.
The incident sparked a multi-agency operation involving the Environment Agency, Lancashire County Council, United Utilities, Lancashire Fire and Rescue Service and Lancashire Police.
Around 23,500 litres of unleaded petrol leaked from the tank over a 29-hour period. Some 7,000 litres was recovered at the site and the remainder escaped into the sewer system and watercourse.
Mark Easedale, an environment manager for the Environment Agency, said: ‘This pollution incident had a dramatically negative impact on the local community and the environment, with Langwood Brook and the River Irwell severely affected.’
A week after the incident, officers from the regulator found that fish populations downstream of the Langwood Brook were around 90% lower than those found upstream, he added.
A spokesperson for Tesco said: ‘We sincerely regret the fuel spillage incident at our petrol station in Haslingden and we’re sorry for the impact it had on the local environment, our customers and the community.
‘This was a deeply unfortunate isolated incident and one for which we have taken full responsibility,’ he said.
Tesco has inspected other petrol stations and introduced real-time monitoring systems to prevent similar incidents, he added.
The prosecution was brought jointly by the Environment Agency and Lancashire County Council.
Tesco pleaded guilty and was charged under the Environmental Permitting (England and Wales) Regulations 2010 and Contravention of Regulation 6(8) of the Dangerous Substances and Explosive Atmospheres Regulations 2002 contrary to s.33(1)(c) of the Health and Safety at work Act 1974.
The supermarket was fined £3m for the environmental offence, and £5m for the health and safety breach. It was also ordered to pay costs of £35,434 to the Environment Agency and £22,000 to Lancashire County Council.
