Ennore oil spill: Water samples indicate leak occurred at CPCL, says report

The Tamil Nadu Pollution Control Board (TNPCB) said analysis of samples collected from near the Chennai Petroleum Corporation Limited (CPCL), in the aftermath of the oil spill in Ennore in December 2023, clearly shows that the leak was from the company premises.

In a report submitted before the Southern Bench of the National Green Tribunal (NGT) on January 11, the TNPCB said the oil and grease samples collected on December 9 from storm-water ponds within the CPCL unit premises ranged from 46 mg/L to 96 mg/L as against the standard 10 mg/L. This clearly indicates that oil and grease got mixed with the storm-water drain at the CPCL unit, the report said.

Meanwhile, during the hearing of a suo motu case, the counsel appearing for CPCL said TNPCB is yet to investigate other units in Manali. CPCL, since the beginning of the hearing, has contended that “the leak is not from their premises” and asked the TNPCB to probe the other 200-odd industries in the area.

In response, TNPCB’s counsel said the Board is investigating other industries too.

The TNPCB report says that as per the Indian Coast Guard, about 24 kL of oil spilled into water. Following an assessment on January 4 after the clean-up, the Coast Guard said no trace of oil was observed in the waterbodies and adjoining areas and the prevalent discoloration was due to “sewage discharge”.

The Indian Institute of Technology Madras (IIT-M) is in the process of assessing physical measurements of oil depth in Buckingham Canal and Kosasthalaiyar River. For this, the institute has furnished a proposal of ₹1.04 crore to conduct an environmental impact assessment that will help devise a management action plan for the restoration of Ennore Creek.