We dug a 6.5 inch bore well at our site in Doddatgur Village, Electronic City Bangalore upto 600 ft.
Bore Well details:
1. Got a rock at 120ft, and casing pipe has been installed up to 120ft, along with Plastic casing pipe(10inch dia.) for about 23ft.
2. At 220 we got rock with white in color with silky texture (I am not sure about name) and we got water with 1 inch output(as per driller)
3. At 260 to 280 we got 1.5 inch water source(as per driller)
4. At 300ft we got granite with black and white patches
5. From 300 to 600 ft same granite has been continued
Around 220 to 260 ft I have noticed some boulders coming out. The boulders of size may be 5 to 10cm, but I have notice very few only.
We have dug the bore well on 7th April 2009, on 17th June 2009 we are trying to install submersible pump(2hp with 27stages), it went up to 310ft only. The mechanic says silt got settled at 310 ft, he says we have to get cleaned. When I check with my driller, he says, we did not notice any silt at the time of drilling, but he says, boulders may have blocked the bore well. When I tried to pump the water, we got around 1 inch water, continuously 3hrs on 17th June after that we stopped the motor. Quality of water was muddy some time, after that it was very clean. On 18th June we pumped the water continuing slowly for 3hr morning and 5hr in the noon.
Now I got confused, whether I have to get it cleaned the bore well and install the motor at 500ft level or not. What is the assurance that, my bore well will not give trouble again. Is it worth to get it cleaned now.
Guruhema Prasad N
guru@esi-india.com