The civic body on Wednesday lifted water samples in and around its dump yard at Vellalore.
According to sources, with help from officials from the Tamil Nadu Pollution Control Board, the Corporation lifted samples at 18 locations - six of those inside the dump yard.
Of the remaining 12, the Corporation lifted water samples from six houses, an open well, and bore wells used for public distribution of water.
MDMK Sate Youth Wing Secretary V. Eswaran, who had filed a case against the yard before the National Green Tribunal’s Southern Bench, and a few residents of the area were present when the officials lifted samples.
At the 18 locations, the officials collected two litres each.
Corporation sources said Wednesday’s was the first such exercise and this would henceforth be a routine exercise to collect water samples in and around the yard, every six months.
They clarified that the Corporation lifting the samples had nothing to do with the NGT case.