Removing sand from 32' dug well

[SmdCarpenter]

Hello all,

Looking for some ideas on how to remove sand from my 32' deep dug well, it is 36" wide with 2' concrete rings stacked over one another to form it,

The water comes through weep holes at what appears to be 27' deep , unfortunately after 60 years I have accumulated sand that has left my current well bottom at 28' so I only have 1' of water...not enough to run the submersible pump I have as the motor would be embedded in mud.

Is it worth hooking up a spare shallow well pump I have setting its pipe halfway through the 1' of water leaving 6" of water below the pipe and hoping it can pull the 27' lift (I'm basically at sea level) and being super careful with usage as a temporary solution?

With it only being 36" wide once I put a ladder down the well there isn't really much room to shovel after maneuvering around the ladder, plus it is dangerous in a variety of ways and I hear air supply would be an issue and I don't have readily available help to haul the buckets up.

 

[Reach4]

I would look into an air lift pump.

https://www.youtube.com/results?search_query=well+cleaning+air+lift

 

[Sponsor]

 

[Valveman]

Yeah you can make an air vacuum with a 30' piece of 1 1/4" PVC pipe and a 1/4" air hose with a couple of elbows at the bottom. Doesn't take a very large compressor if you stay with 1 1/4" pipe. Larger pipe requires more air.

 

[SmdCarpenter]

Awesome idea I have a decent air compressor, I'm going to get on making this and give it a try today or Monday.

I googled the idea as well and a few mentioned having the air nozzle be turned upwards, should I have the air hose end facing down into the bottom of the well or up? Was thinking I can zip tie the hose to the pvc pipe.

 

[Reach4]

Awesome idea I have a decent air compressor, I'm going to get on making this and give it a try today or Monday.

We look forward to the pictures.

https://terrylove.com/forums/index.php?threads/pump-and-tank-advice-please-borehole-supply-in-the-uk.61806/#post-460420 #20 has some nice pictures. This is a very different well, and very different sand from what you have, but you may find that and the other posts in the thread to be interesting.

 

[SmdCarpenter]

That thread was a good read, the copper spiked end with u shaped air attachment was especially ingenious. I'm going to try and replicate that though unfortunately I can't solder well enough to add the u to the pipe end but I will use some elbow fittings to keep the nozzle pointed up.

I do worry about how much water I need on hand as agitant. I have 50 gallons in a rain barrel next to the well, the wells pump is currently removed so I can't draw more water from it at the moment but there is 50 gallons down there. I suppose if I have to do a little bit every half day or so as the well fills with water I can do it that way.

 

[Reach4]

You may have enough water entering the well. But you could also have the output of the air lift pump go to a settling container, and let that overflow water back into the well.

After doing your work, you will want to sanitize your well and plumbing system. I would consider getting some chlorine test strips and pH test strips on order. Put bleach and vinegar on your shopping list.

https://terrylove.com/forums/index....izing-extra-attention-to-4-inch-casing.65845/ is my sanitizing write-up for liquid bleach down a casing. This is not at all what you would be doing, but you might find the pH and test strip comments useful.

 

[Valveman]

You can drill a hole for a 1/4" nipple about an inch or so from the bottom of the 1 1/4" PVC pipe. Put one 1/4" elbow with a short nipple sticking up inside the 1 1/4" pipe. Put another 1/4" elbow outside the 1 1/4" pipe to attach the air hose from above. If you drill the right size hole through the 1 1/4" PVC so a short 1/4" nipple is a tight fit, it will seal good and hold everything in place. Flat bottom on the 1 1/4" PVC is all you need to pick up sand or other loose material. But you can point it or saw tooth it if needed to do some digging with. Oh and I would use 1 1/4" sch 80.

 

[Reach4]

I expect that you can use a bigger pipe size with a higher CFM compressor. A 50 CFM compressor could drive sand and water up a larger pipe than 5 CFM would. Pressure would be about 15 or 20 PSI maybe, but volume needs to be sufficient. You also may need to limit the flow for a given pump.

http://www.baski.com/Portals/0/Documents/Baski Air-lift Pumping Table.pdf is not the same situation, but it does give some numbers for CFM vs diameters. I feel they are probably overestimating the needed CFM for a given diameter, but at the bottom they say you want less air if surging helps you. I expect that surging helps you for this sand pumping job.

Maybe somebody can find a better chart. http://www2.ca.uky.edu/wkrec/AirliftPumps.htm is for a much smaller lift. https://etd.lsu.edu/docs/available/etd-04082008-123312/unrestricted/FINALCOPYBSJend.pdf around page 11 seems to be getting into some design stuff. I am not feeling up to it at the moment.

 

[SmdCarpenter]

I can borrow a big tow behind jackhammer style compressor from my father in law , my home compressor is a twin tank oil filled 8.7 cfm Emglo with a high duty rating. Would it make a noticeable difference in compacted mud sand which is what I assume I'll get after the first foot or so if I have the better compressor? Is 1 1/4" pipe still a good size for a 8.7cfm compressor ?

As far as reusing water, I think what I have is too close to muck or mud to be able to extract the water in a settling container I am going to read up on them tonight but I think I'm going to have to do this in steps as I don't have a way to get a decent quantity of backup water here to use.

I was getting the compressor and pipe ready today. Have a helper for Tuesday to move the muck as we pump it out. Will take photos to post to document progress. Will try to round up some water this weekend to keep going as long as we can.

 

[VAWellDriller]

I do this all the time on smaller diameter wells.....I may be wrong, but I don't think it will work in this case.....you usually need some submergence for this to work and with only 1' of water in the well........ would love to hear if it does work. Another thought; I have a zoeller sump/sewage ejector pump that I sometimes dangle around and bump up and down on the bottom of wells like yours....it works pretty well to get out sludge sometimes. Hopefully you well produces good, so the pump can have something to water down the sand and muck.

 

[SmdCarpenter]

Would depth be a problem for me with the zoeller pump as the distance from the top of the well to the current bottom is 27'? I was worried the atmospheric issues would keep something like that from pumping the muck up and out.

If I end up having to buy two 275 gallon ibc barrels and having the pool water co, come fill them with a tanker to use as water to get this thing cleaned out I'll do that, can always use them as rain barrels later on. Not like it is an option to not have water after all.

 

[Valveman]

The zoeller pump is a submersible that can pump from a few inches of depth. Just need to make sure the one you use can lift more than 27'.

 

[SmdCarpenter]

Reading up on all the zoeller pumps now and their spcs to figure out the right one, I plan to eventually put a small bathroom in my basement with a pit setup so the pump would get use later on and wouldn't be wasted money.

I could also use it hooked to a chain(I bolted a steel plate at the top of the well I can hang it from) with a hose connection to my casing water outlet pipe (which is stubbed off right now after I removed the submersible and it's pvc drop) and wire it to my pressure switch to use it as a temporary water supply pump for the house while I am working through this issue. By using the chain I could adjust the depth as necessary to work with the low water volume I currently have while I work on lowering the bottom.


My well fills fairly fast so if I did this in stages I might be able to use the zoeller to store up a few hundred gallons of water in barrels as agitant then put it back down the well giving me two or three feet of water and then run the air lift Pump setup. It is raining today and I have 200 gallons filling into rain barrels I can use also to give me more water depth.

Also, it seems like if I cut the legs off the bottom of the zoeller (cleanly so I could weld them back later) I could really drag it along the bottom to maximize the mud that gets pulled up without necessarily needing to keep as high a water level.

 

[VAWellDriller]

Its a 140 series...they have two models, one makes 50' head one makes 72'.....not sure which one I have but it pumps about 30 gpm through red rubber 1" hose and will pump the hell out of fine sand.

 

[SmdCarpenter]

Any experience with it and mud ? Wondering if the bigger 270 series would handle that better.

 

[VAWellDriller]

It will pump mud and sand, but you can't just set in on the bottom and leave it...you have to carefully lower it and hover/bounce around so it gets some clean water mixed in with the muck. It will be very heavy...we use hoist truck but you could setup a tripod with pulley over the well to make it easier.

 

[SmdCarpenter]

Well I tried with my compressor @ 80psi, some 1" pvc cut to a point on the end, the 3/8" air line with 1/4" ends I had attached to the pipe right where the point end stopped (couldn't fit the 1/4" elbow through a hole in the pipe so had it turned up taped on right where the point ended point was 6" or so).

Got nothing unfortunately, didn't pull up anything, had about 50 gallons of water in the well (1' depth as it is a 36" circumference ) , moved the pipe around some, had it buried in sand, pulled it above sand, just didn't get anything coming up the top.

On to the next attempt will try one of the Zoeller pumps. On the plus side the point sunk in a good foot when I pressed down moderately and it was pretty much all sand not mud so it should suck up.

 

[SmdCarpenter]

Update #2

Got a Zoeller 152 pump with a 40' max head, it is pumping out sand great...my problem is lack of water to help flow, ran out the 12" of water in the well and then used up 100 gallons from rain barrels.

I was running 1" pvc pipe up from the pump. Have a small pile of sand (maybe 5 gallon buckets worth ) on the grass now where I dumped the water, going to just have to hit this thing a little everyday as the well fills back up. As I gain more depth and hence more water in the well I'll get more time out of each pump out. I could see a small indentation where I was pumping..I am moving the pump around some and pulling it in and out as I pump.

Going to see if I can have the pool water co. Come and fill the well once while I'm simultaneously pumping out and then maybe a second time. If I ran 2000 gallons through this thing I might be able to make a big dent in the sand pile at the bottom.

 

[Reach4]

You still don't think you could benefit from a settling barrel/box for sand? Even water that does not look clear could be useful in the early stages.