Pipeline Break (Poseidon Pipeline Spill); Gulf of Mexico

Gulf of Mexico | 2000-Jan-22

Initial Notification: At 1159 CST on Friday, 22 January 2000. the NOAA SSC was notified of an oil spill in the Gulf of Mexico off the Louisiana coast. The location of the spill was 60 miles offshore. The spill resulted when an anchor from a semi-submersible drilling rig dragged across and damaged a 24" pipeline at both the impact site and at a platform more than a mile away. Oil was released from both locations. The water depth was greater than 400 feet. The initial release volume, based on the amount of oil transferred between the time of the incident and shut in was 1839 bbl. The line was owned by Equilon Pipeline and identified as part of the Poseidon Pipeline System. The NOAA SSC relocated to the Shell Command Post at the request of the USCG to support the on-scene incident commander. Preliminary trajectories suggested that the oil would move west and north. Landfall was not predicted for several days. The type of oil was a medium sour crude with an API gravity of 31.5. Such oils may form persistent tarballs and be transported long distances. Skimmers were activated. Given the potential for environmental injury from the spill, dispersants were evaluated and approved under the RRT6 preapproval guidelines by the COTP Morgan City. The sea state (10-15 knot winds and 4-5 foot seas) was ideal for oil dispersion. Between 1530 CST and dusk, a total of 3000 gallons were applied (1000 gallons by DC-3 and 2000 gallons by DC-4). The SMART team from USCG Gulf Strike Team was launched and provided visual monitoring. Observers clearly observed a dispersant plume and not just surface herding. It was estimated that 75% of the surface oil had been dispersed. Dispersant operations ended due to darkness. During the evening and night, overflights were conducted with both IR and SLAR to maintain contact with the oil. USCG district 8.