Utah-based Sinclair Oil Corporation agreed the settlement with the Environmental Protection Agency (EPA) after breaching the Clean Air Act at plants in Caspar and Sinclair, in Wyoming, and in Tulsa, Oklahoma.

In addition, Sinclair bosses agreed to spend more than $72m on new and upgraded pollution controls to reduce harmful emissions from the three refineries.

The controls are set to reduce annual emissions of nitrogen oxide by approximately 1,100 tonnes per year, and sulphur dioxide by almost 4,600 tonnes.

They should also result in additional reductions of volatile organic compounds (VOCs) and particulate matter from the each of the sites.

VOCs and sulphur dioxide can contribute to respiratory disorders such as asthma and reduced lung capacity, as well as damaging ecosystems and reducing visibility.

“EPA’s vigorous enforcement of environmental laws shows polluters that they need to act responsibly,” said Granta Nakayama, assistant administrator for EPA’s Office of Enforcement and Compliance Assurance.

“Our fellow citizens in Wyoming and Oklahoma will breathe cleaner air thanks to today’s settlement.”

Ronald Tenpas, assistant attorney general for the Justice Department’s environment division, said: “The department remains committed to working with EPA and states to bring industries such as the refining industry into compliance with the nation’s environmental laws.”

Sinclair chiefs are also set to spend $150,000 on supplemental environmental projects in Oklahoma, including £100,000 to install new controls to reduce emissions of particulate matter from the City of Tulsa’s fleet of rubbish collection vehicles.

The state governments of Oklahoma and Wyoming will share part of the $2.45m fine with EPA.

The refineries covered by the settlement have the capacity to produce nearly 160,000 barrels of oil a day.

Kate Martin

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