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News Releases from Region 08

Sinclair Oil to pay $1.6 million penalty and install additional pollution controls at Sinclair, Wyoming Refinery

Agreement resolves violations of 2008 agreement to reduce pollutant emissions

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Richard Mylott (

DENVER – The U.S. Environmental Protection Agency (EPA), the U.S. Department of Justice, and the Wyoming Department of Environmental Quality (DEQ) today announced that Sinclair Wyoming Refining Company (Sinclair) will pay $1.6 million in penalties and install additional pollution controls to resolve violations of air emissions limits and monitoring requirements at its refinery in Sinclair, Wyoming. The settlement follows actions by Sinclair to install approximately $20 million in pollution controls at the refinery and requires the company to take additional measures to reduce harmful emissions of sulfur dioxide.

“EPA is committed to working with our partners to ensure that the terms and conditions of enforcement agreements are met,” said EPA Regional Administrator Gregory Sopkin. “This settlement holds Sinclair accountable for exceeding the emissions limits agreed to in a previous settlement for Clean Air Act violations and requires the company to implement additional pollution control measures to secure cleaner, healthier air for the people of Wyoming.”

"As principal steward for protecting Wyoming's air resources, the Wyoming DEQ's efforts, and coordination with EPA, have resulted in a consent decree amendment that resolves DEQ's allegations against Sinclair and places Sinclair on a path to return its Refinery to compliance with Wyoming's environmental laws and requirements," said DEQ Air Quality Administrator Nancy Vehr.

Today’s consent decree amendment resolves alleged violations of state and federal air emissions limits and monitoring requirements, including those established in a consent decree entered by the United States District Court for the District of Wyoming in 2008, as subsequently amended. The alleged violations at the Sinclair Wyoming refinery include exceeding sulfur dioxide (SO2) emissions limits at the flares and the sulfur recovery plant’s tail gas units, and failing to operate, maintain and certify continuous emissions monitors (CEMS) as required.

Sinclair has installed a Central Amine Facility and upgraded its flare gas recovery system to reduce emissions and advance compliance with air emissions limits at the facility. Under today’s agreement, Sinclair will undertake several additional measures to reduce flaring and improve CEMS operations. Sinclair has also agreed to complete several projects to secure the efficient operation of the flare gas recovery system. Additionally, the stipulated penalty provisions in the consent decree are being modified to provide further incentive for Sinclair to comply with the consent decree emission limits.

The settlement is subject to a 30-day public comment period and final court approval. To access the agreement, visit:

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