In 2024, one of the biggest corporate polluters, Phillips 66, announced that it would be closing its Wilmington and Carson, CA oil refineries by the end of 2025, after over 100 years of operation. Now that the sites are closed, the Los Angeles Regional Water Quality Control Board is the primary authority overseeing site remediation, which is the cleanup of contaminated properties.

This brief focuses primarily on the Carson Phillips 66 site and the community of Carson. We explore existing research about the community health impacts of living near a refinery, how Carson is overburdened by pollution, and why aggressive and proactive remediation is necessary for health after a refinery closes.

Key Findings

• Oil refineries emit toxic chemicals that impact the health of adults and children living up to 20 km (12.4 miles) away, with people living within 5 km (3.1 miles) experiencing the strongest impacts. Oil refineries also contribute to climate change, which has widespread health and economic impacts. 
• Over 80,000 Carson residents live within 5 km of the Carson Phillips 66 site. Nearly all are BIPOC and a third are Asian. The entire city of Carson is within 10 km of the site.
• Phillips 66 is only one piece of the story. Multiple other refineries and thousands of oil wells are located near Carson. Available data shows that Carson residents are overburdened by pollution, especially from toxic releases, fine particulate matter, hazardous waste, and cleanup sites. Rates of cardiovascular disease and asthma are high compared to other areas of the state. It’s important for all sources of pollution to be addressed, including through full cleanup of the Carson Phillips 66 site. 
• When a refinery closes, the health concerns don’t automatically go away. Currently, there is no standard requirement around refinery site remediation or who pays for it even though toxic pollutants can linger in communities long after refineries close. In October 2025, an Environmental Investigations and Cleanup report from the California State Water Resources Control Board noted the presence of some chemicals (described in full text) at levels above regulatory screening levels at the Carson Phillips 66 site, indicating a potential impact on water quality and human health.

Carson residents face a legacy of pollution from multiple refineries and oil wells. Improving the community’s health requires that each and every source of pollution is remediated. 

The Phillips 66 closure is an incredible step in the right direction, but will only translate to healthier communities if the Los Angeles Regional Water Quality Control Board uses this moment to push for levels of clean up that were previously unavailable while the refinery was in operation.

The Board has the opportunity to be a national leader by developing a remediation plan that is community-driven, complete, holds Phillips 66 financially accountable, and ensures that the site is transformed into something beneficial for the community. Doing so will set a precedent of what remediation should look like not only in California, but nationwide.