Pumping air and pressure drops

[macombvan]

I have a point well that I put a new pump and pressure tank on. I still have the same trouble I had with the old system(the addition of the pressure tank does help at the start of water usage). It takes a really long time to get water. Eventually it will build up pressure and when water is used, comes out great at first. As the usage continues ( a shower for example), the flow drops off to hardly anything. If we leave the cabin for even up to a month and come back, the system holds its pressure. The water sits about 5 feet from top of the pipe and when I measure the well with string and weight, I get 21 feet. Any ideas without pulling it up and installing a new point and pipe?
Thanks

[Raucina]

Maybe the screen is encrusted in which case being so shallow you can tremie some muriatic acid down to the screen area and agitate it or brush it. Or just dump it in and rod away to get it to the water zone. Pump it a lot and then chlorinate it too. The worst is that you will eat up whats left of the screen in which case you were going to pull it anyway. If your neighbors get water then probably the water table is not suspect.

Groundwater and wells is a old standby book and gives formulas for acid addition and safety instructions for this unpleasant operation which is not often done on residential wells..

[speedbump]

Do not put Muriatic acid in your well, tremied or otherwise. You can be killed. It has happened before and I hope it does not happen again. That is the worst advice I can imagine. Muriatic fumes can kill you in a hurry and Muriatic acid reacts violently with hydrogen sulfide. If you are standing out in the open with a breeze blowing it is still dangerous.
http://www.cdc.gov/niosh/face/stateface/mi/01mi061.html

There is a product called Nu-Well tablets. They are made by the Johnson company and are designed especially for treating encrusted well screens. The work is done at the screen by a slow dissolving tablet. Water must be added to the well continuously for them to work good as they must be dissolved to make the acid that does the actual work. Instead of Sulphuric, the acid is Sulphamic if memory serves. They are safe and effective.

Heres a link to a supply company that sells them:

http://www.ramortsupply.com/welldrilling.htm

bob...

[Rancher]

Perhaps if people knew that Muriatic Acid was really Hydrochloric acid, they might think twice. The Chlorine fumes can permantely damage lung tissue, or kill ya...

Rancher

[Raucina]

Considering that you can buy both those items by the multiple gallon at any true value hardware or big box store, I would say the odds of of injury are pretty low.

I would be more afraid of MEK and laquer thinner and paint stripper. Just like guns gotta know how to use them.

[Raucina]

Now that you mention it, a good mix of those two and a small detonator could also clean that screen more quickly and increase the yield greatly....

Have not tried it personally though.

[speedbump]

Dynamite caps can seperate 1-1/4" pipe at the joints also. I know that one from experience. The well was in a crawl space. I couldn't pull the pipe, they didn't have NuWell tabs yet. I had some dynamite caps laying around so figured what the heck. This nice old lady might get some water after all. Well after the blast, the top 5 foot of pipe was not connected to the rest of the well anymore. You could turn it with your fingers.

bob...

[macombvan]

Thanks to all suggestions.
I will try the Nu-Well tablets next year when I open the cabin again(winterized now). If there is a check valve down in the well near the point, will the chemicals get to the point to clean it? I don't know if there is, but thought I would ask.
It was also suggested to me to shoot a 22 down the well. Didn't sound like something I will try.
Van

[Raucina]

Sulfamic acid is relatively inert prior to wetting and the powder is not dangerous to the skin like Muriatic acid liquid.

Sulfamic acid reactions break down calcium and magnesium to sulfamates which are highly soluble in water

Muriatic creates sulfates which are much less soluble

Sulfamic is less agressive in action on metals and pumps

Muriatic is easy to get and quick and certain in action. Requires more art to use.

Sulfamic is in powder form and so can be packaged and sold by well companies as well elixer. Both work. Both make toxic gas in their reactions so both can kill during the process.

Neither acid oxidizes bacterial slime and thus the chlorine is good insurance if one does not have a camera in the well.

[speedbump]

You defined your well as a point well, so I would assume there is no check valve in the well. If there is, you will have to pull the point. If the well is 1-1/4" it has no checkvalve in it. If it is 2" it could have a Bremer check on top of the screen which will render the Tablets useless.

bob...

[hj]

Muriatic acid is dangerous in the wrong hands, but it is also used in swimmng pools for ph control. The fumes are dangerous which is why the instructions say to use it in a well ventilated area. But, I doubt that it would react with hydogen sulfide, since that is already a combination of an acid and a base. It will react violently with caustics.

[speedbump]

Pour some on an old pump half that has sulphur in it. Or pour it down a well with sulphur. It will foam and the fumes will overtake you if your not real quick. And wow; does it stink later.