The Director of The Energy and Resources Institute (TERI) based in New Delhi will be in Mumbai on Friday to meet the Maharashtra Pollution Control Board officials to offer help in containing the oil leak that happened from MSC Chitra. TERI has developed ‘oilzapper' technology and the institute wants to use it to contain the contamination here. “We have used this technology successfully for nearly a decade on land. It is completely organic and has no side-effects,” Dr. Banwari Lal, Director of TERI, told The Hindu on phone.
The process of using it is called bioremediation. In this, a combination of microbes or bacteria is used to clean the oil spill. The microbes feed on oil and degrade it completely. They emit carbon dioxide which is absorbed in the atmosphere. These microbes die within few hours and form food for other marine animals.
It can be used on sea as well as on land, with certain variation of microbes. This is time consuming (takes around two months) but much preferred to the chemical method. In the chemical method, emulsifyers are sprayed over the slick. That does not clean up the oil, but makes it invisible. “The oil settles on the sea bed contaminating it,” Dr. Lal said.
Bioremediation may sound like the magical solution to all the woes caused by the spill. But it isn't that easy. The contamination has spread in a wide area on the Mumbai-Raigad coastline. At present, due to the monsoon and rough sea, in situ (at site) bioremediation is not possible as the high tide will wash away the microbes.
The other method is creating makeshift bioremediation tanks near the affected area. In this method, the contaminated sand has to be physically scooped out and shifted to the tank. Considering the expanse of the contamination, it is going to be very difficult and cumbersome to scoop out tonnes of sand to the tanks. “But if that can be done, we are completely sure we can treat it,” Dr. Lal added.
Impact on ecology
The other problem is, the contaminated areas themselves aren't homogenous. Some have mangroves, others have rocky patches and still others have sand. Even time is running out. If the contamination is not cleared within a month, it will have untold impact on the ecology here. “We will be too late if we wait for the monsoon to get over,” he said.
A visit to some of the coastal areas like Peer Wadi, Devli-Danda, Mankeshwar, Kegav, Vashi only confirm the worst fears of the environmentalists. The lowest level of the food chain has already been affected. Fish samples have been found contaminated too. Mangroves in many places have lost their seeds and have turned black due to oil deposition. But help seems to be coming soon.
“Uran mangroves have already lost their seeding,” Deepak Apte, Assistant Director, Bombay Natural History Society, told The Hindu after his field visit. “The mangroves, their seeds are completely covered in oil. Even the rocky patches there are completely oil-ridden. This is worrisome,” he said.
The Vashi creek is one of the worst-affected. All one can see is the blackened mangroves to the height of at least 2 meters. “The oil has reached the high tide mark. This can be seen on these mangroves,” said Swapna Raut, a volunteer at the Bombay Natural History Society. A thin film of oil can be spotted even from the bridge above the creek.
Another concern is the tea, milk powder and biscuit packets that have come floating on the shore. Many families in the coastal villages have taken bagful of these packets.
Movement restricted
Now, with the fear of contamination due to pesticide bottles, the police have restricted movement in the areas along the beach in some places. “We have secured the entire area are from Karanja to Peer Wadi,” said police Sub-Inspector Dhamal at the Uran police station.
