I have a 380 feet borewell in my farm in Southern Tamil Nadu. This borewell currently has a yield of 3000 to 3600 litres per hour. The borewell was drilled in 2012 and a pump was installed a year ago in Feb 2016. The water from the borewell is a bit muddy but more of a pale white muddy mix (I have not tested the water and I do intend to test it) over the last 1 year. I have a feeling that mud has collapsed in the borewell over a period of time (I also intend to clean the borewell) as I had drilled the borewell in 2012 upto 380 feet but the pump is not going below 350 feet.
I also have a feeling that some of the fractures are not yielding water as against my observations during the borewell drilling where the yield was estimated at 5000+ LPH
I have been advised by some contacts of mine to blast explosives in the borewell between 100 to 225 feet after pulling up the pump, column pipes, cables (the outer casing pipes are till 60 feet depth) to open up some new fractures as well as expand existing fractures to increase the borewell yield
I am writing to seek advice from experts on this forum if bursting explosives inside a borewell a recommended process to open up new fractures and expand existing fractures, and if experts feel blasting is a good solution, what precautions should I take to protect the existing yield in the borewell as well as the outer casing pipe. Ofcourse If I go down the explosives blasting route I will be cleaning up the borewell
Suggestions from experts on this forum will be very much appreciated
Your borewells seems to be surrounded by clay based soil or loam. I guess this from your message that the water is muddy and 2) there is cave in.
Usage of an explosive will not solve your problem and on the other hand, the entire well may go out of use.
Secondly, dont use any explosive substance without necessary permissions from your local authorities. Unauthorised usage of explosives will put you into great trouble.
The advise given by Sri Ykamesh is correct and there is much possibility for the bore well to be blocked
I have personally witnessed two incidents of such, where the bore wells ,even the existing yield was vanished. Apart from this, there is risk also involved, if any unfore Seen araises, at the time of blasting. Can’t say.
Now , I opine your bore well is suffering with wrong placement of outer casing pipe. It might not have properly seated in to the Rock hole.
As stated by you, your bore well is giving muddy, white colour water, right from the beginning. It clearly speaks that the mud in the bore well is sucked by the pump. You have also stated that water yield is good in your bore well.
Now I hope that you better go for repairing your same bore well. Take out the casing pipe , and insert it again in to the groove of the Rock. Then drill/flush the bore well up to 380 ft or more.
Thank you very much @ykamesh, @g.p.rao, @saravanakumargcses for your feedback. I will not go for the borewell blasting, I will just clean up the borewell alone. Your feedback is very much appreciated
regards