Oil spill contamination way above permissible limit: TERI
Mumbai   15-Sep-2010

The extent of oil contamination along Mumbai's coast caused by the recent oil spill is far above permissible limits, according to the first development report on the oil spill conducted by The Energy and Resources Institute (TERI). The report highlights an urgent need for a regulatory standard for oil contamination in soil.

TERI, along with the IndianOil and INS Kunjali, had carried out clean-up operations at Awas beach, Alibaug, on August 20 and Navy Nagar on August 28 respectively. According to TERI, Awas was mainly contaminated with tar balls and other biodegradable debris - samples collected from the spot contained 60,000 mg/kg of total petroleum hydrocarbon (TPH). At the INS Kunjali Navy Nagar site, which was more severely affected by the spill, the oil contamination was 3,81,000 mg/kg. The international permissible limit of TPH is much lower at 1,000 mg/kg. Considering the high concentration of TPH at Navy Nagar, TERI has stated that the clean-up process would take longer than Alibaug.

It claimed that the beach was physically cleaned and contaminated soil, tar balls and other pollutants were transferred to a secured high-density polyethylene (HDPE) lined bioremediation site near the sea beach post where their 'oilzapper' technology was used to rid the debris and soil from oil and oily sludge. Oilzapper uses bacteria derived from various naturally occurring and non-pathogenic bacterial cultures to eat up the contaminants and convert them into carbon dioxide, in four months.

On Tuesday, TERI director Dr Banwari Lal said in a press release, "The contamination in both the sites has been way above the international permissible limits. At present there is no permissible limit set for oil contamination in soil in India. We hope that the concerned regulatory authorities set the standard limit so that the polluters can be penalised."

Lal has said that in both the sites, tilling of the oily waste is being carried out manually on a weekly basis and the samples are collected on a fortnightly basis for analysis. TERI said the contamination was due to the furnace oil stored in the ships, which is heavier and more difficult to degrade than crude oil.