Panaji, Sep 2 - Goa's environmental watchdog is concerned over the pollution caused by over a dozen mines to the Selaulim reservoir that is the only source of potable water for the southern parts of the state.

Chairman of the Goa State Pollution Control Board (GSPCB) Simon de Souza said the board has increased the frequency of water testing to check for traces of heavy minerals found in mining silt in the reservoir. The pollution is being caused by 14 mines.

'We have increased the frequency of inspection from quarterly to once every month. We are looking out for traces of heavy minerals which could find their way into the reservoir,' de Souza told IANS.

The action by the GSPCB follows allegations by the opposition parties that the 14 mines operating around Selaulim were dumping silt and mining rejects into the reservoir, reducing the water body's depth and polluting it.

'This is our department's response. We are more vigilant now. Inspections and examination of the water will be held every month for the next year in order to keep pollution levels in check,' de Souza said.