It's no mystery that exhaust from automobiles is a major source of pollution. Chevron officials say that's why their new expansion plan is so important.
"The bottom line is that they'll be cleaner automobiles and cleaner trucks on the road," Chevron public affairs officer Steve Renfroe said.
Chevron has to help make that happen by making gasoline with less sulfur. It's called the Clean Fuels Project.
"We're taking the refinery's existing equipment and changing the service that that equipment is in," Renfroe said. "It's like we're replumbing the refinery almost."
Chevron first announced plans for the project last September. Officials say some folks have expressed concerns about the local environmental impact of the process. But they say they don't expect a significant change in the air quality.
"We've followed all the rules. We've talked to DEQ; we followed their rules. We've talked with EPA; we've followed their rules. But really we've done even more than that because we're installing an additional $1 million of environmental control equipment that we're really not required to install," Renfroe said.
Chevron officials say money is a big part of this project. It will cost about $100 million to complete.