I've seen both centrifugal and diaphragm pumps described as 'trash pumps'. I'm not sure if either is appropriate in my case. Here's the situation - perhaps those with experience/expertise could advise/suggest.
I had a well dug last summer on our place on Texada Island. The area it's in is almost pure sand, and naturally the excavation was caving in and widening as the digging proceeded. At about 12 ft. down we hit an obvious spring, and the excavator operator decided it would be difficult and pointless to go any deeper. Now, at this point he should have perhaps dumped in a bucket of rock before placing the plastic casing, but he was anxious about the hole filling in, and didn't take the time. After placing the casing he did surround it with lots of rock, and we put a plastic ground water barrier around it a few feet from the top (He'd never heard of bentonite).
The water is good, the recovery rate is not bad but not nearly as good as I would have expected given the size of the flow we hit. Sticking a
10 ft 2x4 down the well I discovered that apparently several feet of sand has migrated into the bottom of the well, so that its effective depth is more like 8 feet than 12.I'm thinking of pumping out the entire well, including the several feet of sand in the bottom. While I"m at it, I'd go down there and drill some holes in the sides of the plastic casing. Of course this should have been done before the thing was put in. Right now water can only enter via the bottom, and must perc through all that sand.
So my questions are:
1) What type of pump is best used to pump (submerged, quick) sand? I expect there to be no rocks, sticks, etc, just sand. 2) Is the well liable to just fill back in quickly anyway? 3) If I do get it pumped out, would dumping a couple of feet of rock into the casing help prevent sand entry, or would the sand just fill in between the rocks and then be even harder to remove than just sand?There's a Chinese importer here in B.C. who sells what appears to be a Honda clone centrifugal Trash Pump on eBay, for a fraction of the cost of the Honda. Other than the usual comments on Chinese machinery, anyone have any personal experience with these things or this guy?
Thanks in advance to all.
Mickey