The Martinez refinery is operated by Marathon subsidiary Tesoro Refining & Marketing Company LLC and the air district says the penalties were assessed for flaring that occurred when the refinery was idled in response to the COVID-19 pandemic.
Marathon announced in late 2020 plans to convert the Martinez refinery to one that processes renewable feedstocks like soybean and corn oil rather than crude oil from fossil fuels.
The air district alleges that during the pandemic-related shutdowns, Marathon improperly flared vapors from storage tanks and loading racks and also flared gases while shutting down, idling and decommissioning refinery process units.
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Other violations allegedly involved visible emissions from smoky flares, excess air pollution emissions and delays in completing necessary repairs, according to the air district, which said all violations related to the case have since been corrected.
"The health of our communities should be non-negotiable," BAAQMD Board of Directors chair Davina Hurt said in a statement. "This substantial penalty demonstrates the air district board's unwavering commitment to hold polluters accountable and safeguard the health of our communities."
Marathon officials were not immediately available to comment on the air district's penalty.