The Kentucky Department for Environmental Protection’s Environmental Response Team (ERT) is working with the United States Coast Guard and the responsible party to help clean up an oil slurry spill after an accident on the Mississippi River Sept. 3.
Cleanup of the spill began Tuesday, Sept. 15.
Two tow boats collided on the Kentucky side of the Mississippi River near Columbus in Hickman County during the evening of Sept. 3, which resulted in a large incident response over Labor Day weekend. One of the barges carried as much as 1 million gallons of a petroleum product called slurry oil. This barge was damaged and spilled about 120,000 gallons of this oil into the river. The cleanup and removal of the oil is expected to be completed this week.
Kentucky’s ERT is part of the incident Unified Command. ERT is teamed with the US Coast Guard and the responsible party to manage the investigation, discovery, and cleanup of the
accident and the spilled oil. The responsible party is ultimately responsible for paying the costs of the salvage and cleanup operations, but costs for the cleanup of the oil are initially paid for by a trust fund established after the Exxon Valdez oil spill in Alaska. Those funds are then reimbursed by the responsible party.
The type of oil in this particular spill, slurry oil, is heavier than water and has not caused a highly visible surface slick. Slurry oil is what remains after crude oil is cracked and distilled; it’s thick and sticky and forms a blob on the bottom. Even though it’s out of sight, it’s very much not out of mind. Just because the spill is on the bottom, doesn’t mean it can just be left there. Operations are underway to get it cleaned up as much as possible. Water samples that are being collected show that the oil does not appear to be affecting water quality downstream of the spill.
Operations at the scene include removal of the remaining oil from the damaged barge into a receiving vessel in a process called lightering. Divers have evaluated the river bottom because of the presence of endangered mussel species in the vicinity and don’t believe the mussels are in the area because of unsuitable sand where the oil came to rest. In addition, bottom sampling will be used to further define the extent of the bottom substrate oiling.
Once the oil is located and characterized, every attempt will be made to remove it from the environment. Options being considered include dredging and diver-assisted vacuum removal.
All of the agencies and contractors are making progress in the efforts to remove the remaining oil from the damaged barge, remove and decontaminate the barge, and locate and plan for removal of the oil.
Lightering of the vessel was completed on Sept. 7 without incident by heating the thick product and pumping it into an empty barge. The damage to the barge was inspected by divers and the barge has been removed from the river to a facility where it will be made secure and then transported to a repair location in Illinois.
The spilled oil has been pinpointed to the river bottom close to the location of the impact with an area equivalent to two football fields. This has been verified using a combination of high resolution side-scan sonar, divers, and weighted oil snares.
Flyovers, shoreline assessments, and monitoring and sampling of water in the vicinity of the spill have all verified that this spill has had minimal impact to the surrounding environment. But leaving the oil in place is not an option since it is thick and sticky and could oil anything it touches on the river bottom, including endangered mussels and endangered fish habitat.
Plans for removal and disposal are complete and completion of these two tasks will be the final stages in bringing this unfortunate incident to its conclusion.
To see video of the dredging of the slurry oil, click the links below.