Pumping Sand

[Brad Perkins]

My 8 month old well was drilled 160 ft and my pump is set maybe 5 ft off the bottom. It's cased all the way thru mostly limestone shale. I have a flow inducer sleeve as well on a 10 gpm 1/2 hp pump. This well only makes around 1 gpm so initially I developed it by hooking up a Cycle Sensor to pump into the field until the hole ran dry and repeat. After a couple weeks it cleared up really nice.

I didn't use any water for a couple weeks after I hooked it up to the house and noticed the water smelled some and had a slight yellow tint to it. My solution was to run the water hard for a couple days and problem went away. I finally plumbed the water into a holding tank have been running like that for a couple months without issue.

Last week that all changed when it appeared like the check valve in the pump stuck open and siphoned out my tank. That back washed my sediment filter into the well. When the pump came back on to fill my tank, it turned my water into a red horrible mess. I drained the tank and refilled but with limited success. The water will not clear up. I can pump in 150 gallons and it be clear enough I can see the pump sitting in my tank but then later that day it will pump murky water to where I can't see the bottom and it also smells slightly of sulfur. But something else I noticed now is very fine sand in the filter. Before it would fill the filter with a fine clay and water was very clear. Now I see more sand and water is murky.

My question is.. Should I raise my pump? I also thought about how I am filling my tank which lately has been to drain it and pump my well dry to refill. While normal use I don't pump in nearly as much water at a time. Could pulling the well all the way down be causing this? Also considered restricting the flow via a ball valve on my tank to fill it slower. Oddly enough I have not experienced another check valve failure again either. I've since cut the pipe short in my tank so it's not submerged in the water.

Btw my wife is complaining about her hair and skin showering in this water so I need a little help. I have a softener as well but it won't take out whatever is making the water murky.

What should be my next step? I'm concerned the pump is now sitting in sand... how much is too much? And again this stuff is super fine powdery sand.

 

[LLigetfa]

The well might need to be sanitized. Have you tested the water for iron content?
I would pipe it with an air gap so that it cannot siphon back.
I would use a dole valve to limit the GPM of the pump.
Is it slotted casing or bottom fed? How long is the sleeve? If it does not extend far below the pump motor I would make it longer and raise the pump higher.

 

[Sponsor]

 

[Reach4]

5 ft off of the bottom is unusually low. I would raise the pump if I thought I would have adequate water supply.

You can clean the well of sand and other accumulated sediment by

1. having a big engine-driven air compressor pump air down a pipe to the bottom, and having sand blow out the top like a geyser. You would usually want to hire that done.
2. Use an air lift pump to suck the sand with a smaller compressor and over a longer time. Restriction: this needs the static water level to be fairly high -- about 50% of the well depth.

You could also put in a topside Lakos Sandmaster to extract the sand. https://www.lakos.com/homeowners/

I don't know if their Sub-K would be useful for you. I am not a pro.

 

[Brad Perkins]

I might be off on my 5 ft calculation. Installed the pump myself and honestly didn't measure the depth. It's not a ton of work to chop 10 ft off and drop the pump back in.

The casing is slotted with a gravel screen.

How much can I safely limit the flow? What gpm should I target before I declare that strategy a loss?

That sand extractor is cool but that will have to be the last line of defense. How well do they work?

 

[Reach4]

The casing is slotted with a gravel screen.

In retrospect, you would have used finer slots and finer gravel. However the hope is that there is a mix of sand size outside of the gravel placed outside the slots. We hope the finer stuff made it through, but the courser stuff got snagged up in the gravel pack and is building a finer gravel pack with time.

How much can I safely limit the flow? What gpm should I target before I declare that strategy a loss?

1 gpm is a reasonable number with your flow inducer.

However you might want to repeat your full-flow to the field technique to see if that helps with your current setup.

That sand extractor is cool but that will have to be the last line of defense. How well do they work?

See https://terrylove.com/forums/index....ment-mitigation-whole-house-irrigation.54955/
https://terrylove.com/forums/index.php?threads/lakos-sub-k-sand-separators.66384/
https://terrylove.com/forums/index.php?threads/sandy-well.75929/

 

[Brad Perkins]

Something else I noticed that might indicate an issue...

A few times I witnessed the cycle sensor reporting 15 amps from my pump when it first starts. Drops down to 3-4 amps in maybe 5 seconds. Normally it spikes at 4 amps and settles around 3 amps. Does this behavior indicate pump buried in sediment?

I'd love to pump full flow into the field but Id have to splice in a T and valve. Hoping I can clear it pumping into my tank and draining it out. The water has to travel thru about 100 ft more pipe now

 

[Valveman]

Sand in the pump can make it hard to start sometimes and the Cycle Sensor will see that.

 

[Reach4]

I'd love to pump full flow into the field but Id have to splice in a T and valve. Hoping I can clear it pumping into my tank and draining it out. The water has to travel thru about 100 ft more pipe now

Dig down near the well, and tee off to a yard hydrant? You put gravel at the bottom of the yard hydrant to allow a place for the water to drain when you shut the hydrant off.

 

[LLigetfa]

Lift the pump off the pitless and see if it will drop down any lower. If it doesn't then probably the space under it filled with sand. The sleeve at least should keep the motor from getting buried in sand and overheating.

Is the holding tank open air, meaning not pressurized? With a 10 GPM pump filling a holding tank, meaning there is zero pressure on the outlet, it will pump more GPM than if it was filling a pressure tank. How many GPM depends on the water level. The more GPM, the more it motivates sediment which is fine if you are trying to develop the well but not afterwards.

If you have a large enough holding tank to supply your needs, then consider restricting the pump to match the GPM the well produces. Initially you said it produces 1 GPM but after you developed it, it could produce more. You have to find the sweet spot where you can draw it faster but not so fast it motivates sediment. That is my exact predicament with my well. After developing it, I can now draw around 7 GPM without motivating too much sediment. What fine sediment I still get is trapped by my iron filter that has AG media.

 

[Brad Perkins]

Measured the depth and my pump is 10 ft off the bottom. I don't feel I need to mess with that but I need to develop my well more and have a couple options. Feel free to toss out other ideas.

Option A is to install another pitless adapter in the casing above ground that I can set the pump on every day for a couple weeks. That way I can develop the well all day and night only setting it back to fill my tank. Handling the pump and pipe full of water daily has me concerned though...

Option B is to splice in another line with a valve to control the flow. I don't want a yard hydrant since this line is not controlled by a pressure switch. I don't like the idea of a pipe sticking out of the ground and I don't want to have to dig down 3 ft in the future if I need to flush the well again later.

 

[Brad Perkins]

Anybody think of a good reason why option A is a bad idea other than the fact I'll have a pitless adapter protruding from my casing?

 

[Reach4]

People usually recommend changing the o-ring on a pitless when you do pump work. At least keep a spare 0-ring and appropriate silicone grease on hand.

 

[Brad Perkins]

Just wanted to report I installed another pitless adapter above ground yesterday. Didn't go well as I couldn't screw into the pitless without cross threading it. Had to carefully hook up a rope to catch it in case the threads gave out. Then I ran into a tricky detail that I didn't plan well. Not all pitless adapters are made the same. In fact I had 3 different brands and none interchanged. Got super lucky and found the same oem that made mine but in a different box at TSC. Otherwise I'd been digging up the ground to replaced the original pitless with a different model.

But in the end I got it done and pumped every 2 hours for 24 hrs and my well is now 100% clear like it had been . I'm going to swap it back and pump again after the wife gets caught up on laundry. Then I will shock it and hope to pump the bleach smell out in 48 hrs. I used too much water this time. Softener reneged on me after I set it to vacation mode.

This method to flush your well isn't recommended if you have more than 200 ft of 1 inch poly pipe in the water. My 170 ft of 1 inch poly really tested my man limits.

Here's a pic of my setup. My well pics are too big to upload

 

[Reach4]

This method to flush your well isn't recommended if you have more than 200 ft of 1 inch poly pipe in the water. My 170 ft of 1 inch poly really tested my man limits.

When you recirculate the treatment water (with vinegar and bleach) back into the casing, you don't use up the water. Do use the flooding volume.

I run my recirculating water through a cartridge filter, because I have one available.

 

[Reach4]

This method to flush your well isn't recommended if you have more than 200 ft of 1 inch poly pipe in the water. My 170 ft of 1 inch poly really tested my man limits.

An engine hoist could maybe lift high enough for that.

 

[Brad Perkins]

An engine hoist could maybe lift high enough for that.

That's true. I used my tractor to hold it and a floor jack at first when I was afraid of dropping my pump in the well.

 

[Reach4]

This method to flush your well isn't recommended if you have more than 200 ft of 1 inch poly pipe in the water. My 170 ft of 1 inch poly really tested my man limits.

I used my tractor to hold it and a floor jack at first when I was afraid of dropping my pump in the well.

I would think you could do the lift with the tractor, but would need a helper to work the hydraulic control while fitting the pitless pieces together. Don't forget to get an o-ring and silicone grease on order.

 

[Brad Perkins]

I would think you could do the lift with the tractor, but would need a helper to work the hydraulic control while fitting the pitless pieces together. Don't forget to get an o-ring and silicone grease on order.

Problem with the loader is that it doesn't lift straight up so binding was a concern. Plus I didn't any help that day.