The fears of Comba residents about their wells being contaminated with a fuel-like substance have proved to be true. The analysis report of the water samples taken by the Goa state pollution control board (GSPCB) has confirmed the presence of oil and grease in the wells. While the samples of the water of two wells were found to have oil and grease contaminants to the extent of 6 mg/l, the third sample contained oil and grease contamination of 5mg/l. There are no permissible levels for oil and grease in drinking water.
It was earlier reported that residents of Comba were apprehensive of possible fuel seepage into the groundwater from a fuel storage tank of any of the two petrol stations situated in the locality.
Calling the analysis report’s findings unacceptable, GSPCB sources said on Tuesday, “Oil and grease are generally found in waste water that is discharged into storm water drains. The presence of floating oils in drinking water calls for serious investigations.”
Adding that the report has only just been prepared and a decision on the steps to be taken to identify the source of contamination will be taken soon, sources said Goa state pollution control board (GSPCB) will, nonetheless, forward the report to the Margao municipal council (MMC) and the South Goa district magistrate soon to take necessary action. Analysis of the water samples for other parameters too, revealed unusual levels of contamination.
The pH level stood at approximately 5.40 for the three samples, way lower than the acceptable limits of 6.5 to 8.5, the test report reveals. The pH level is the measure of acidity or alkalinity of water. Knowledgeable sources explained that in general, water with a low pH (less than 6.5) could be acidic, soft, and corrosive.
“Water with low pH levels could leach metal ions such as iron, manganese, copper, lead and zinc from the aquifers and plumbing fixtures. Therefore, water with a low pH could contain elevated levels of toxic metals, and have associated problems such as a metallic or sour taste, and staining of laundry, if used for washing clothes,” a source said.