How do get thru gravel?

Discussion in 'Pumps and Tanks Well Forum & Blog' started by ron in sc, Mar 30, 2007.

  1. ron in sc

    ron in sc New Member

    Messages:
    80
    Location:
    South Carolina
    I decided to try to go a little deeper to get my old well working better. It's 22 years old and when it doesn't rain for awhile I had to prime it every time before I used it. Anyway I pulled up old wellpoint, probably a mistake, and now I can not get past 12'. I had filled the wellhole around the old point with gravel when I put it down a long time ago. That gravel is now an issue.

    How might I get thru it?
  2. sammyhydro11

    sammyhydro11 Previous member

    Messages:
    709
    Location:
    Massachusetts
    I would go with a new hole all together. The only way to get past that point if it is gravel would be to use more weight. Going with a fresh hole would also give you a frsh zone to be drawing water from. Overtime the outside area around the well screen can collect alot of fines and even oxidized iron that plugs up the pore spaces in between the sediment. Even going deeper beyond that zone the sediment that is plugged up above it would still have an influence on production. I would move away from your original spot atleast 10'. I hope that makes sense to you.

    SAM
  3. ron in sc

    ron in sc New Member

    Messages:
    80
    Location:
    South Carolina
    Yes, that does make sense but in the particular area which is convenient to use I could only go about 7 feet away form the original well.

    I did that and could get no deeper than 18 feet. the sand is just to difficult to get thru. I'm using pvc and a pvc well point with holes in the end. To get down I had to use a sand shark next to the well point.


    Any suggestions?
  4. sammyhydro11

    sammyhydro11 Previous member

    Messages:
    709
    Location:
    Massachusetts
    It sounds like your jetting the point into the ground. I would switch to steel pipe. You can pound that point beyond where you are hitting some refusal. How deep was the old well? Having to prime your old setup might not have been from the water table being lowered but it could have been a problem with the waterline or pump. How deep is it to water?

    SAM
  5. ron in sc

    ron in sc New Member

    Messages:
    80
    Location:
    South Carolina
    Do you mean steel for all the pipe and the well point?

    Old well was about 20' as I recall.

    Now I have water at 18' but pump loses pressure and them gurgles. If I stop it for any lengh of time I have to reprime to get it to run again.
  6. sammyhydro11

    sammyhydro11 Previous member

    Messages:
    709
    Location:
    Massachusetts
    Use steel pipe with a stainless slotted well screen.You were definetly over pumping your old well. I would try to get your new well to atleast 30'. I like to see atleast 5 to 10 feet of water over the screen,10'would be ideal but it all depends on what the material is like at that depth.Depending on the how much the well draws down at that depth you might have to put a jet assembly in the well and use a deep well jet pump. Hey you know what, there is a simular thread that will explain this all. It's called " drive point well question " and was posted by "sucker dave". You will find all the info on that thread very useful. Check it out,and if you have any questions feel free to ask. Your situation was so simular that i think you should read it over.

    SAM
  7. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    27,056
    Location:
    Cave Creek, Arizona
    ell

    The theoretical limit for a pump is about 27' down to the water. As a practical matter once it gets down past 20'-23' you will lose your water supply.
  8. ron in sc

    ron in sc New Member

    Messages:
    80
    Location:
    South Carolina
    As part or my search to help me with my problem I did see that thread; it has tons of useful information. However, the last post would imply that SuckerDave was unable to resolve his issues and may have had a professional drill him a well. I've looked into that too but there is really not go place for a drilling rig to get on my property. Front yard is very small and lot is on a cul de sac. Front yard is landscaped with plants everywhere.

    I've did go to Lowes and looked at the stainless steel points. They have 60" models and 36" models. They have all the couplers and cap for pounding. Which length would be best?

    I read the directions and it seems that it would be real difficult to get a hammer or pile driver on a 5' lenght of galvanized pipe. Any suggestions there?

    I could make the pile driver, but not sure how to get lead inside of 2" or 3" pipe. I read that you made one, how did you do that?
  9. sammyhydro11

    sammyhydro11 Previous member

    Messages:
    709
    Location:
    Massachusetts
    If you read that thread there is a part where we were discussing the importance of seeing the material that you are placing the well screen in. When driving a well point you are hoping that the depth that you set it to has material porous enough to pass the amount of water that you are looking for. You are also hoping that the slot size of your well screen is large enough to alow enough fines through to develop the well. In daves case it could have been a little bit of both the screen size and the consistancy of the material.In some cases the material wont pass enough water at all no matter what size screen you have. In your case the well depth was one of your issues.Whith auger drilling you can see the material coming out of the ground at each depth you are at so it takes the guess work out all together. I would check your local rental shop for a drive weight,most shops have them. Here is a link to a site that has some basic instructions on driving the well point. I have never used a sledge hammer to drive a point and would suggest a drive weight. fdungan.faithweb.com/well.htm

    SAM
  10. ron in sc

    ron in sc New Member

    Messages:
    80
    Location:
    South Carolina
    That linik has more helpful information. After reading it I decided to press on with a different technic.

    I cut teeth in the bottom of a 2" schedule 40 pvc pipe and used it as a casing. Used a 3/4" pvc pipe down the center to get casing down. With a lot of effort I'm down to 21' 6". Not sure if I can get any deep with the pvc casing.

    I've not seen any more yellow sand. Went thru a couple of areas of gray to grayish black sand and I'm now in little shells. Are the little shells good for water bearing. Also the water coming up go noticabley cooler when I had the tiny shells coming up.

    From what I've read I'm supposed to put point down and then pull up casing. I'm not inclined to do that. I was thinking what about putting a stainless steel point down and pounding it down. If the point is 4' long I'd pound it down 4' which would put it past the casing. Would that be ok?
  11. sammyhydro11

    sammyhydro11 Previous member

    Messages:
    709
    Location:
    Massachusetts
    Are you jetting ahead of the 2" to get it deeper?The shells are an indication of a marine type sediment or silt. The darker colored material is an indication of organic material. You could telescope an 1 1/4" screen down the 2", get it beyond the 2" casing the length of the screen or place the screen at the bottom of your 2" and pull back the 2" to expose the screen.Are you close to the ocean?If you are close to the ocean I would be concerned about sodium seeing that you have some shells coming up in the water but i have seen shells in areas that were miles away from the ocean too. I think you need to get to atleast 30'. I would keep washing ahead of the 2" with some smaller pipe to loosen up the material and then continue trying to go deeper.

    SAM
  12. sammyhydro11

    sammyhydro11 Previous member

    Messages:
    709
    Location:
    Massachusetts
    You also have to keep in mind that if you get accesive drawdown durring pumping and you need a jet assembly to lift the water,your casing diameter needs to be 2". Thats one of the main reasons why you should pound a 2" steel well.

    SAM
  13. Wet_Boots

    Wet_Boots Sprinkler Guy

    Messages:
    798
    Location:
    Metro NYC
    Speaking of excessive drawdowns and 2 inch points, is the use of a tailpipe on a packer assembly an effective remedy for a low-producing point? Is it always necessary to use the full theoretically-required length of tailpipe?
  14. ron in sc

    ron in sc New Member

    Messages:
    80
    Location:
    South Carolina
    Are you jetting ahead of the 2" to get it deeper?
    Yes


    Are you close to the ocean?
    Yes, I'm in Charleston, SC


    I got to 23' and I can not seem to get any further. What do you think about connecting the 2" casing to a mudhog? Would that accomplish anything? Like create an area below the casing for the screen that could be used to hold water.
  15. sammyhydro11

    sammyhydro11 Previous member

    Messages:
    709
    Location:
    Massachusetts
    If you can create an area below that 2" casing with that tool you were talking about and the area is larger than the casing itself you should be able continue with the 2" pipe.

    SAM
  16. sammyhydro11

    sammyhydro11 Previous member

    Messages:
    709
    Location:
    Massachusetts
    Weteboots,
    you could do that as long as your packers are snug and there isn't any water leaking past them.

    SAM
  17. ron in sc

    ron in sc New Member

    Messages:
    80
    Location:
    South Carolina
    I'm calling a diaphram pump a mudhog. Do you think that a diaphram pump will be able to create space below the casing? If so, I can rent one.
  18. sammyhydro11

    sammyhydro11 Previous member

    Messages:
    709
    Location:
    Massachusetts
    Those mud hogs are good for developing but seeing how deep the water table is it might not work out. That well still isnt deep enough to try anything. It needs to be atleast 30'. I still suggest a 2" steel well with a stainless well point. If that well needs a jet assembly you will have no way of getting one down the well.

    SAM
  19. ron in sc

    ron in sc New Member

    Messages:
    80
    Location:
    South Carolina
    I'll try to get deeper tomorrow so I can at least identify where the water table is located.

    So my options are either:
    2" pounded well, or
    3" well casing with jet pump assembly

    Will an 1 1/4 pounded well work?

    What is significance if any of the water in the 2" casing starting at 7' and going down to bottom at 23'
    Last edited: Apr 1, 2007
  20. sammyhydro11

    sammyhydro11 Previous member

    Messages:
    709
    Location:
    Massachusetts
    I think what you should do is start pulling that 2" pvc back a few feet at a time and check your static water level each time. There is a good chance that you are hitting some layers of clay that are holding water in between them. That would explain the difficulties of getting beyond 18' and having a water level at around the same depth. i think once you get beyond that 18' layer you are in a zone that has two clay layers,one at 18' and one at 23' and its holding water between them.Its called a confining layer and it puzzled the hell out of me the first time i encountered one. You can start off having a static water level at 40' in a 60 ft. well and then when you pump it off and let it recover it only recovers to 50'. I think that if you have a water table at 7',your water bearing zone is going to be between 7' and 18'. try pulling the well back to 17' and see what you have for a static water level. The reason why i say 17' is because you have an open end pipe and you need to alow some space on the bottom to allow the water to come in. Another question is,how high are you in relation to the closest body of water? That can give you an idea as to where the static water level could be. Once you know where the static water level is we can determine what size well to go with.

    SAM
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