20 Aug Bay Area Air District Reaches Settlement With Tesoro Refinery on Pollution Monitoring, $75K Fine

The Tesoro refinery and Mount Diablo are seen from the 232-acre Pacheco Marsh in Martinez on March 16, 2023. (Ray Saint Germain / Bay City News)

By Bay City News

The Bay Area Air District has finalized a new pollution monitoring plan at one of the five refineries in the region that had their previous monitoring plans “disapproved” in 2023, the air district said in a news release Tuesday.

Tesoro Refining and Marketing Company, a subsidiary of Marathon Petroleum, agreed to implement a new fenceline monitoring system to detect hydrogen sulfide and other pollutants at six points along the Martinez facility’s perimeter. The company also agreed to pay a $75,000 fine.

The air district required each refinery in its nine-county jurisdiction to create a new monitoring program to replace their “open line” systems that used a beam of light to detect hydrogen sulfide over a larger area.

The point monitors will deliver more precise data, which will also be shared more with the air district and the public by making it available online for download.

The company further agreed to make quarterly reports of pollution levels available and hold a public meeting sometime before the end of the year to solicit public feedback on what sort of data the public would like to see.

Tesoro’s facility is the second of the refineries to come to an agreement with the air district on a new monitoring program, following the approval of Chevron’s Richmond refinery in June.

The Tesoro refinery has faced numerous fines in the past from state and federal regulators for a variety of violations. It is in the process of being converted from a crude oil refinery, operations of which were shut down in 2020, into a renewable fuels refinery that would focus on vegetable oils and other renewables. The project’s final environmental impact report was released in June.

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