Which Gasoline Should I Buy?

When we wrote about the expansion of BP's Whiting plant in Indiana, commenter Eugene asked "So since I still need to buy gas, who should I be buying it from? We didn't have the answer but the Sierra Club did. They reviewed the records of the eight largest U.S. oil companies and concluded:

Top of the Barrel
* BP
* Sunoco

Middle of the Barrel
* Royal Dutch Shell
* Chevron
* Valero Energy Corporation
* Citgo

Bottom of the Barrel
* ExxonMobil
* ConocoPhillips

They documented reasons; you can read them at ::Sierra, and you can even order a free ::handy air freshener. via ::grist