CHENNAI: With a majority of oil slick scooped out off the coast, the Coast Guard is contemplating spraying of imported biodegradable dispersants in the shallow waters where chemical dispersants are not recommended due to ecological reasons.
The oil spill occurred due to the collision between two ships near Ennore.
Coast Guard officials told Express that the Indian Institute of Technology (IIT)-Madras has been entrusted with the task of doing the necessary analysis and recommend the best environment-friendly dispersant.
Sources said dispersants are used to break up an oil slick floating on the surface of water into small droplets that can be carried away by waves. Traditional dispersant formulations contain a blend of surfactants in a base of organic solvent. There are concerns regarding the aquatic toxicity and environmental impact of current oil-spill dispersants, which are typically not food-grade materials.
The officials said that in India supply of bio-degradable dispersants is scarce; so it is likely to be imported. “IIT- Madras and a few Mumbai-based companies are coordinating to find a best possible solution. Tamil Nadu Pollution Control Board (TNPCB) will be certifying the product as eco-friendly before use,” sources said.
When contacted, a source in the Department of Environmental and Water Resources Engineering Division at IIT-M said the Coast Guard has sought a report and the analysis is being carried out. “The effectiveness of the dispersants depends on the oil type. The Material Safety Data Sheet (MSDS) of dispersant will tell us whether the dispersant is eco-friendly or not,” sources said.
Coast guard officials said the pollutant has liquified from being a thick tar-like substance after days of manual cleaning. The remaining oil/petroleum forms a film, which prevents oxygen from entering the water, resulting in damage to coastal and sea life. “So, we would be using skimmers as well as dispersants that have ability to emulsify in water and disperse the oil.”
At Bharathiyar Nagar, where a majority of work is currently centered, the number of volunteers have been scaled down and the remaining clean-up work is expected to be completed in a week’s time.