Recently, the Karnataka State Government has announced that it is exploring possibilities of recycling the water stored the tunnels of the Kolar Gold Fields mines to meet water supply demand. The water in KGF is known to be contaminated with heavy metals and arsenic.
Below is the newspaper article about it printed in the Times of India, Bangalore edition on the 20th of December.
If this goes through, it will definitely require closer monitoring and regular testing of the water from these areas.