help.How to re-case a well ?

Discussion in 'Pumps and Tanks Well Forum & Blog' started by johncook, Dec 13, 2010.

  1. johncook

    johncook New Member

    Messages:
    4
    Location:
    brentwood ca.
    I have a old well that feeds my house.
    it has a 8''ID steel casing that is rusty and more like a egg shell than steel.
    I assume i need pull up my jet valve, get 6'' PVC pipe glue as i drop it down to the bottom
    of the well, fill around the outside with pee gravel and reinstall my jet valve,is this correct ?
    do i make holes from the top of the water line to the bottom? do i seal the bottom end of the pipe?
    how far up from the bottom of the well should my jet be? i have sandy soil.
    thanks in advance for the help.
    my system needs a complete overhaul but first things first,every time i touch the well i can hear case flakes falling into the well,need to secure the hole first.[is that a bar joke?]
    thanks again john
    ...................................................................................................................................................
    1hp sears jet pump,2lines[1 1/2''-1 1/4'' into well,45gal diagram tank [with ripped diagram] 50' to bottom,24' to waterline,47'to jet valve
  2. valveman

    valveman Moderator Staff Member

    Messages:
    4,381
    Location:
    Lubbock, Texas

    This will leave you no way to clean the steel casing. Somtimes the steel will rust over and shut off the water coming into the well. If that happens, you will need to drill a new well. Might save some money to just drill a new one now.
  3. justwater

    justwater Well Drilling/Service

    Messages:
    327
    Location:
    FL/GA
    what you are thinking is not completely out of the question. you really need to know exactly how your well was installed though. what is casing depth?, what is total well depth?, does it have a screen or is it an open hole drilled underneath casing?

    goal here is to install pvc (with 8" seal on bottom) inside the old steel. NO HOLES IN THE NEW PVC, as the entire reason for doing this is to prevent surface water from seeping through a rusted hole in the steel and getting inside the pvc. you want all your water to come from BENEATH the well casing as it should, not from holes rusted into the sides. i would use portland cement to fill the void between the 2 pipes rather than pea gravel.. for reasons already stated. if done correctly, the old steel pipe will be irrelevant. not gonna be a real easy job. have to pull out whatever is in the well now, then install correct amount of 5-6" pvc with 8" seal on bottom. the pvc will be awkward, and likely have to be pushed the whole way down, and this is gonna stir up the well big time.

    see what kind of info you can come up with on how your well was installed, then u can go from there. this is something you'll probably only be able to do once. kind of a "make it or break it" fix. because once you get the pvc with seal in place... cement or not.. the rusty holes will allow soil/sediment/whatever to fall onto the top of the seal, and you wont be able to budge it later.
    Last edited: Dec 14, 2010
  4. valveman

    valveman Moderator Staff Member

    Messages:
    4,381
    Location:
    Lubbock, Texas
    In our area we would use .035 perforated 6” PVC from 24’ to 50’ and cap the bottom. Then we would gravel pack between the new 6” and old 8” up to about 23’ from the surface. Then we would bentonite seal a couple of feet above 23’, and cement from about 21’ to the surface.

    Our water does not come from below the casing. Cementing between the 6” and 8” all the way up would shut off the water completely. I know some areas do have water that comes in from below the casing. So I would find out where the water enters the well before I poured anything down hole.
  5. justwater

    justwater Well Drilling/Service

    Messages:
    327
    Location:
    FL/GA
    Agreed, that's why I suggested he should find out how his well was installed first. So is it possible that 8" steel pipe is slotted or has holes to allow water in? I was always under impression that people with old steel wells would set solid casing to water zone, drill it out, then a screen below if needed.. heck I don't know though. Valveman is right, many different well methods.. do plenty research before u attempt anything.

    so to reword.. You may not want to seal off all the casing depending on well type, but u do want to be sure u don't get surface water in the well.
    Last edited: Dec 14, 2010
  6. valveman

    valveman Moderator Staff Member

    Messages:
    4,381
    Location:
    Lubbock, Texas
    That is the way we do oil wells except we drill "through" the water zone. As a kid I leared how to use a torch slotting steel casing for water wells. I have seen a lot of old wells with thin wall steel casing, we call it "stove pipe" casing, and that maybe what is was before it was casing.
  7. justwater

    justwater Well Drilling/Service

    Messages:
    327
    Location:
    FL/GA
    How bout that.. earlier dad was telling me that he had a friend in new mexico that use to slot his bottom couple joint of casing with a hack saw. I'm so use to ground pressure around here that it's hard for me to picture this stuff!
  8. johncook

    johncook New Member

    Messages:
    4
    Location:
    brentwood ca.
    HI guy's
    I think i got ahead of myself.
    the problem started when my pump lost prime, tried to prime but it had a leak inside the well,
    pulled up jet valve/foot valve and found the press. line came off valve.[the nipple and the line end looked o.k.] I thought easy fix.
    so i cut off 3'' and reinstalled with new clamps and heat to get good bite on valve.when i lowered the valve into the well the black plastic pipe
    got it's memory back when it was on a spool[big bend]and scraped all the way down pulling off more rust from the old steel casing.
    when i started the pump i can only get 20psi out of it.
    i opened the chamber part of the pump, the impeller and cover looks good.I think i have a blockage in my jet valve.
    i got a new valve for the pump i have.but I'm afraid if i scrap the side of my well again it will cave in!

    the well is 50' to the bottom,it seems to be rust all the way down,and the plumbob felt soft when it hit bottom,the company that drilled it is gone,it was drilled in the late 50's early 60's. i live about 1 mile from the California delta west of Sacramento at sea level with sandy soil or what we call loam.
    i hope this answer's all the questions.the new well would be easer but i lost my job 2 years ago when general motors closed down the dealer i worked at for 15years.
    thanks again john
  9. valveman

    valveman Moderator Staff Member

    Messages:
    4,381
    Location:
    Lubbock, Texas
    That jet assembly is always going to cause problems if you have rust falling off in the well. Might consider a submersible pump which would solve that problem.
  10. johncook

    johncook New Member

    Messages:
    4
    Location:
    brentwood ca.
    would that[new submersible pump]be better than re-casing the well and replacing the jet valve?
    won't re-casing with PVC stop the rust problem ?
    what are the con's of re-casing?
    what submersible pump do you recommend ?
  11. justwater

    justwater Well Drilling/Service

    Messages:
    327
    Location:
    FL/GA
    When the casing goes out, it goes out.. No matter what pump u are using. Fixing the well would be my first priority. Without knowing more about how the well was installed, I think a patch similar to valvemans suggestion would be a safer bet. Need to talk to a local well driller an see how the water enters a well where u live. From under casing, or through the sides of the casing..

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