Of the more than 17.3 million barrels per day (bbl/d) of refinery capacity located in the United States as of January 1, 2012, about 44% (or nearly 7.7 million bbl/d) is located along the Gulf Coast. As the map above indicates, there are a number of refineries, some of them very large, situated along the coasts of Texas, Louisiana, Mississippi, and Alabama.

The U.S. Energy Information Administration’s annual Refinery Capacity Report provides capacity information about individual refineries as of January 1 each year. The report identifies refineries that are operable at the beginning of each year. Operable refineries are further classified as either operating or idle. A refinery could be idle for a number of reasons including routine maintenance, unplanned maintenance, or market conditions.

via Much of the country’s refinery capacity is concentrated along the Gulf Coast – Today in Energy – U.S. Energy Information Administration (EIA).