I am planning to implement a 6" bore well with submersible pump assembly. Location: Bilaspur , Chattisgarh.

Boring with vehicle mounted machine is not possible due to space limitation.  Accordingly, the boring work is done using diesel operated machine mounted on tripod. They informed me that for a bore of 6", initially a bore larger than 6" has to be  made till rock is found. After getting rock large size pipe will installed and be rested on the rock to support the  earth materials which may dislodge and fall during drilling in rock due to vibration. However after that, onward 6" hole will be drilled and hence 6" pipe will be installed upto required depth till water stream is found.

I have sone doubts regarding the same.

- Please go through the problem at hand and let me know if the correct form of action is being undertaken.
- Does one need to use higher size bore for primary bore,  than the final bore size?
- Do we need pipe after rock is hit?
- Can PVC /  HDPE / HDPP pipes be used for long term purposes in borewells?
- Please outline the right procedure for boring, borewell assembly installation.

G. Singh
singh.g@hotmail.com