CHENNAI: Though Indian Coast Guard has managed to swiftly remove the oil that is visible on water surface and beaches, the problem is far from over. Several tonnes of oil spilled are sunk and probably entered the water column endangering marine species.
Answering the Express question over Skype from Washington DC during a discussion on ‘Disaster Management: Coastal Oil Spill’, Douglas (Doug) Helton of the U.S. Department of Commerce’s National Oceanic and Atmospheric Administration (Emergency Response Division) said the heavy furnace oil (HFO) that has polluted the Chennai coast was the dirtiest oil and sinks rapidly to the bottom creating all kinds of problems.
“Though it’s a commonly used oil in ships across the globe, there are places in US and other countries where the use of HFO is banned. For instance, heavy oil can’t be used in colder environments like Arctic and Antarctica because it is very persistent and stays in the ecosystem for years. Even 20 years after Alaska oil spill, there are traces of oil still found even today. Oil type is a very key consideration. The US has catalogued several thousands of oil types and their behaviour. Lighter oils are less problematic,” he said.
To a query, Helton said that in US the polluter has to notify the national response centre about the spill immediately and specify the quantum of spill. And, the polluter is mandated to engage a ‘clean-up’ contractor within 4-6 hours after the spill.
However, Deputy Inspector General of Indian Coast Guard (Eastern) MA Warsi, who was the chief coordinating officer for the oil spill clean-up operation, told the Express on the sidelines of the event that the Coast Guard had put in the best efforts to recover the oil in two weeks after the accident. Warsi claimed that the material that was spilled was actually an oil sludge, not the HFO.
The cofferdam of the Dawn Kanchipuram was ruptured and it had sludge, whose volume got magnified when came in contact with water. He also expressed doubts over the argument that the oil has sunk. “We have asked the Department of Environment to carry out a study on quantum of oil sunk to the seabed. The amount may be marginal considering the fact that the area affected was shallow water.”
R S Vasan, regional director, National Maritime Foundation, told the Express that heavy oil does sink and only a detailed environment impact assessment study would reveal the actual damages caused.