New well question

Hello folks,

New member. Looks like a great group.

Gotta well question.

I live in Deep East Texas.

Have recently, like last week, had a new (4") well drilled and completed on my property. The driller found good sand @ between 310' and 360'.

The screen (20' long, stainless steel) was set at ~320'.

When the driller flushed / air lifted the well to purge the drill mud / dirty water / etc, he estimated the potential flow to be between 15 and 30 gpm.

The static level of the water was 70' after about 30 minutes of letting the well sit idle, but eventually it climbed up to 22' from the well head. In fact, it blew the plumbers plug off the top of the well with the air pressure built up in the casing from the water rising.... sounded like an air cannon going off.

When the submersible pump was installed, we ran it till all the 'bad' water had flushed out of the casing. Once we got down to clear water, the gpm settled at about 4 gallons per minute. I calculated this by timing how long it took to fill a 5 gallon bucket... pretty scientific huh?

We've got a 1.5 hp submersible pump and a Flex-Lite FLS120 bladderless tank.

My puzzle is this:

I let the well sit idle to allow it to recover to 'static' water level. Then I turn on the pump, and am able to maintain 12 to 16 gpm, at 10 psi (as read on the guage of my tank). This flow rate can be maintained seemingly indefinitely.

If I dump the pressure by opening all the drain valves, my flow drops to about 4.5 gpm.

I may be just missing some thing in the pressure / volume law, and if so, my instructors at Navy Dive School would be really upset. I wonder if by dumping the pressure at the tank, I'm allowing the water level in the well to drop all the way to the pump.

Any thoughts?

And sorry for the long message.

hal

I've not heard of a Flex-Lite bladderless tank! Most tanks used ou well systems today do have a type of bladder. The large flow for a seemingly indefinate time is probably due to the well storing approximately 1.5 gallons per foot plus the 4.5 gallons per minute recovery of well. Then when you dump the pressure (maximum flow) the stored water in the well is finally depleted to the point the the pumping level has dropped to the point that the pump is now pumping the 4.5 gpm that the well supplies. Don't sweat the Navy Dive School instructors being upset because in this case, everything is the same but different. You are just dumping the pressure at the tank, allowing the water level in the well to drop all the way to the pumping level.
My thoughts: Everything appears to be working fine. . . don't sweat the small stuff!

flex lite seems to be a bladder tank

http://www.flexconind.com/html/fl.html

Thanks guys. The tank in question, as I understand from the driller and all the paper work, is bladderless; fills from the bottom, catching the 'bubble' inside the tank, which gets compressed and makes the pressure. But I'll double check on all that.

Also, was my thought about the water flow. I could almost picture the water pumping out down to the pump. I believe a 'balance' is maintained for a pretty long time with the static level being so high. Thanks for the gut check.


hal

quick update. The driller did not like the cement job (long story on that!), or the production rate of 4 to 5 gpm. So, he drilled a new well for me (at his cost). They just completed it today, set the screen and pump.

The new well makes 15 gpm. Had the water from the first well tested by a local lab, it's good on all counts. The new well is 10' away from the first and the same depth, so it's going to be the same water.

He was going to P&A the first well, but it rained hard last night, so the rig truck couldn't get into position with out making huge ruts. As a result, I now am the proud owner of two 4" wells. I'm going to make the first well my garden water, and hand pump / emergency supply.

If there is a problem with the cement, that well needs to be pluged or it will contaminte both wells.