A "Typical configuration" for a Shallow jet well?

[D1Case]

After a couple years of neglect, I am trying to refurb a shallow well that feeds my irrigation system. It's a 2" jet well, 45 feet deep, with the water column rising to 9 feet deep. I am fairly sure there is a sand point on the end.

Removing the seal, I was surprised to find the 1" suction tube to be about 6 feet shorter (39 feet).
I was also surprised that instead of having a foot valve, the suction side went down to an injector/venturi fitting(?), slightly bulbous area for a lower seal, then ended with a check valve.

While this design seems to work, I was left wondering if there might have been something in that gaped 6 feet, or is this a "typical" configuration? And if it is typical, what would the normal range for the check valve's height above the base?

[LLigetfa]

That is a very normal packer deep well setup. How low to set it depends on how low the water table may get and how much sediment may build up in the bottom of the casing.

[D1Case]

Thanks.
Seeing the open ended check valve had me overthinking it.

[LLigetfa]

I don't know what you mean by open ended. First off, what you describe is not a shallow jet well. A shallow well jet pump uses only a single pipe. A deep well conversion uses two pipes, one for suction and the other for pressure.

[Tom Sawyer]

The water pump pushes a volume of water down one line, through a venturi which in turn sucks water up to feed the suction side of the pump. The foot valve keeps the system primed.