[Public Voices]Will the Sea Remember That Day?

2007 Taean Oil Spill Incident
Severe Damage to Marine Ecosystem
Long-term Monitoring and Attention Needed

Jung Yong-sang, Director of the National Park Research Institute, Korea National Park Service

December 7, 2007. Black waves surged, and cormorants were covered in oil. In a scene resembling chaos, people stamped their feet and sat on the ground, weeping uncontrollably. Fifteen years ago, the worst marine oil spill accident occurred in Taean, Chungnam. A crane barge returning after completing construction of the Incheon Bridge collided with the oil tanker Hebei Spirit, which was waiting to enter Daesan Port. The amount of crude oil spilled in this accident was 12,547㎘, equivalent to 62,735 200-liter drums. The spilled oil quickly covered the nearby sea area, and a month later, tar balls were found in the waters off Jeonnam. To remove the coated oil, various people from across the country participated in volunteer efforts, totaling 1.23 million people. Thanks to the efforts of many, 4,428㎘, a quarter of the spilled amount, was recovered, but due to the nature of the flowing sea, complete removal of all the oil was difficult.

Immediately after the oil spill accident, the Ministry of Environment and its affiliated organizations, including the Korea National Park Service, formed a joint ecosystem investigation team and conducted an urgent survey of ecological damage. Starting with the "Detailed Ecosystem Impact Survey (2008)," the National Park Research Institute has been conducting "Long-term Monitoring of Ecosystem Impact from Oil Spill Accidents" from 2009 to the present. When an oil spill occurs at sea, very serious ecological damage happens. According to the comprehensive analysis results of monitoring conducted since 2008, the number of benthic species in the seabed sediment layer decreased by 70% immediately after the accident, and the abundance of fish in the intertidal zone decreased by 33%. In the case of the finless porpoise, the average number of individuals observed for three years after the accident was about half of the usual 57 individuals. The aftermath of the accident paralyzed the ecosystem in an instant. Although the oil floating on the sea surface is somewhat purified by physical actions of the sea, the oil that penetrated the sediment layer takes a considerable amount of time to remove. In the residual oil survey of the area directly hit by the oil spill, a thin oil film was still found underground even seven years after the accident, in 2014.

Using research data accumulated over more than ten years to evaluate the recovery of the marine ecosystem after the accident, it was found that in 2008, immediately after the accident, the carbon transfer among ecosystem members was 45.6 tonC/㎢, and after more than ten years, in 2018, it increased to 76.17 tonC/㎢, indicating an increase in carbon cycling and a transition to a more productive ecosystem. However, looking at overseas cases, morphological deformities in marine organisms were observed even after a considerable time had passed since oil spill accidents. Considering the maximum lifespan (25 years) of top marine predators such as the black-tailed gull and finless porpoise, long-term monitoring is necessary, similar to the over 30 years of monitoring of the Exxon Valdez oil spill in Alaska.

The National Park Research Institute continues to conduct ongoing research to diagnose detailed ecological changes and build precise data for Taeanhaean National Park after oil spill accidents, and to serve as an institution capable of responding to potential future marine oil spill accidents. Cases of long-term research and extensive data accumulation on marine oil spills are very rare in Korea, and such efforts are expected to serve as a textbook reference for determining investigation timing and methods if oil spill accidents occur again in the future. Natural ecosystems, once damaged, suffer very serious harm and require a great deal of time and effort to recover. Since they are closely linked to human habitats, this is never someone else's problem. Ultimately, the day in December 2007 is a day we must remember?not just the sea, but ourselves.

Jung Yong-sang, Director of the National Park Research Institute, Korea National Park Service