QUESTION
Solution needed for smelly borewell water

I have new borewell of 282 ft, and the water comes out at 60 ft,100 ft and 200 ft. The submersible is installed at 260 ft, but when I start the submersible for 1-2 hours, the water discharged initially is yellow and has a bad smell. After some time the water recieved is colourless water but smells like drainage water.
The distance of drainage line and borewell is around 5 ft and I am in doubt that it might be due to this, but there is a casing installed up to 40 ft. There is another boring in my neighbour around 40-50 ft distance from my borewell and he receeves good water.
I am of strong view that it is due to the seepage of drainage.
Please let me know of possible reasons of this problem along with its solution.

Thanks

by
10 October 2014