Gateway Generating Station is on the southern shore of the San Joaquin River, in Antioch, and is one of more than ten fossil-fuel power plants in Contra Costa County.

In June 2015, a lawsuit was filed against the Environmental Protection Agency to prevent the approval of the station's air-emissions permit; the suit was dismissed in October of that year.

[7] In July 2005, Pacific Gas & Electric acquired the partially-constructed plant from Mirant in a settlement agreement;[3] in 2006 it was approved as a co-owner of Unit 8, and the process of filing paperwork was resumed.

[7][11] Randy Livingston, PG&E's vice president of power generation, said to the Brentwood Press that the project came "ahead of schedule, on budget, and we had no lost-time injuries during the entire construction of the plant".

While Mirant had originally intended to use evaporative cooling for intake chilling, PG&E switched to an air-cooled design due to a desire to avoid drawing water from the nearby San Joaquin River.

[14] Upon its initial construction, the facility was described by the Brentwood Press as "big, imposing, noisy, metallic, tubular, gray, and sculpturally magnificent" but "not sexy".

[6] In 2010, the Trans Bay Cable was switched on, linking San Francisco's electrical grid with distribution infrastructure in the Contra Costa County.

[2] In June 2013, the Center for Biological Diversity submitted a legal notice of their joint intent (along with Communities for a Better Environment) to sue the Environmental Protection Agency for approving the project, claiming that its NOx emissions harmed local communities and "transform[ed] the chemical composition" of the nearby Antioch Dunes, causing hardship for tens of endangered Lange's metalmark butterflies.

[24] In response, PG&E said that Gateway was "state-of-the-art", and that it had entered a voluntary Safe Harbor agreement for 12 acres of its property to be used as dune habitat for the butterflies and plant species.

[25] In July 2017, The New York Times identified Gateway Generating Station as an "investor-owned power plant" and noted that it was represented by the Edison Electric Institute trade association.

[28] In 2014, a steam-cycle performance assessment resulted in an update of the cycle-chemistry manual, upgrade of the chemistry logging systems, and purchase of new analytical equipment.

[31] The CCHSHMP concluded that, while the facility had a management system in place to oversee CalARP requirements, some timelines had not been met due to changes in site leadership.