"On March 25, 2010, Chevron Pipe Line (CPL) was notified of a sheen on water in the vicinity of the 18- inch Whitecap Pipe Line in Ship Shoals (SS) Block 182 area. CPL contacted Apache Corporation, who had recently completed work in this area, and requested their assistance in investigating the reported leak. CPL took operational control of the Mr. Fred (a diver support vessel (DSV)) and began investigating the reported leak. No leaks were found in this area but the search for the leak source continued. After additional over flights it was learned that the origination point could be in the SS 157 area. CPL moved the DSV and initiated a new investigation. The pipeline was shut-in on March 26, 2010, in an attempt to curtail sheen on the water and to help in the identification of the leak. On Saturday, March 27, 2010, the source of discharge was identified as the 18-inch Whitecap pipeline at a crossing with the 36-inch Tennessee Gas Pipeline (TGP) pipeline. The point of failure is not classified as a High Consequence Area (HCA). There was no fire, explosion or injuries. Approximately two hundred and fifty gallons of crude was released. The accident was not reported to the National Response Center (NRC) by CPL. A written report was submitted to PHMSA on April 18, 2010."
Pipeline and Hazardous Materials Safety Administration: http://phmsa.dot.gov/