(KRON) -- The Bay Area Air Quality Management District (BAAQMD) announced Thursday that its highest-ever penalty of $82 million has been assessed against Valero Refining Company over pollution violations at its Benicia refinery. The historic penalty will “benefit the Benicia area and overburdened communities around the Bay Area,” according to the district. The joint prosecution from BAAQMD and the California Air Resources Board stems from a 2019 inspection that found unreported organic emissions from the Benicia refinery’s hydrogen system. The emissions contained benzene, toluene, ethylbenzene and xylene, or BTEX, compounds. The compounds “cause cancer, reproductive harm and other toxic health effects,” air district officials said. “Air District inspectors discovered that refinery management had known since at least 2003 that emissions from the hydrogen system contained these harmful and toxic air contaminants but did not report them or take any steps to prevent them,” a statement released Thursday said. “The refinery emitted an estimated 8,400 tons of these organic compounds in total over this period in violation of Air District regulations – an average of more than 2.7 tons for each day on which a violation occurred, over 360 times the legal limit.” Valero refinery in Benicia, California, on Monday, March 25, 2024. (David Paul Morris/Bloomberg via Getty Images) Nearly $80 million of the penalty against Valero Refining Co. will be returned to communities in the San Francisco Bay Area, according to BAAQMD. In Benicia, $64 million of that will be used to “finance projects aimed at reducing air pollution exposure, mitigating air pollution impacts and improving public health in areas surrounding the refinery.” Valero Refining Co. will be required to reconfigure the Benicia facility’s hydrogen systems to prevent emissions from being released into the atmosphere. BAAQMD will also require a training program for Valero employees on air regulations. 12 cited in Northern California unlicensed contractor sting District officials said the unprecedented penalty is the third major fine assessed against Bay Area refineries this year. A $20 million penalty was announced against the Chevron refinery in Richmond and a $5 million penalty was given to the Marathon refinery in Martinez.