Need help to resolve the borewell issue


I have a borewell which is 412ft deep having a 8" dia. We were using a 12 stage, 5 HP pump, 2" HDPE pipe and best quality power cable and were able to get good water. A few days ago I installed a 7.5 hp pump which was recommended by most of the people to maximise use but after 30 minutes of pumping, the motor was jammed with mud. When I checked the bore, I found that it was now only 290 ft deep which means that 112 ft was filled with yellow mud.

I would like to know as to how I can resolve this problem and retain the borewell. 

Also contacts of suitable experts who can do a hands on evaluation in the Vidarbha area will be appreciated. My contact number is 09630082870.