Experts from IIT-Madras and engineers from the Tamil Nadu Pollution Control Board (TNPCB) on Thursday collected water samples from Tondiarpet, where oil from pipelines has polluted groundwater.

The 10 samples that were taken by the environment division of the civil engineering department of IIT-M will be subjected to gas chromatography-mass spectrometry (GCMS) analysis that will reveal the exact fraction of oil content in the water and what kind of oil it was.

Indumathi Nambi, associate professor at IIT-M, who visited the site, said that remediation would be possible after ascertaining the type of product that had leaked, the amount that was released into the environment and how much of the soil and water table had been contaminated.

TNPCB and IIT-M have also asked Bharat Petroleum Corporation Limited, whose three pipelines pass through the area, to provide data about the products pumped into the pipelines over the past two years.

“This will help in the study and remediation. Perhaps, a new borewell can be dug and undisturbed soil samples lifted,” said a source at TNPCB.

Samples have been lifted from 50 metres south and 15 metres north of the underground pipelines. TNPCB also took samples of the water recently, after residents complained that water from their borewells had been polluted.

BPCL had said that two of its pipelines that had reported a drop in pressure had been closed. Following this, the Central Pollution Control Board last week directed BPCL to stop operating its three pipelines from the Tondiarpet terminal.

More In: Chennai | News