I live in a co-op housing society in Pune. We have constructed a borewell 230 ft deep 15 days back. The borewell is approx 7 ft from a sweage line .There is a sweet smell to the water that is being pumped from the borewell. Also it seems to have foaming at the instant of delivery. This foaming dis-appears after  approximately a minute. What could be cause for the above - sweetness of smell & foaming (lather)?

Rohit
rohitkarnik18@yahoo.co.uk