It is possible that the water is less than 25 feet deep but I wouldn’t count on it.
A regular suction type pump can only lift water 25 foot. For water that is deeper than 25 feet you need a jet pump or a submersible pump etc. This type of single pipe packer ejector is normally used when the water is deeper than 25 foot but not much deeper than 200 foot depending on the model.
For a deep well with a small diameter well casing of less than 4 inches a single pipe packer ejector can be used. The well casing is utilized as the down pipe. A packer is used to separate the water in the upper part of the casing/drive pipe and the suction pipe. Below the packer is the section of suction pipe where incoming water from the well enters. A foot valve may be used at the end of the suction pipe or there is a check valve built into the packer.
The first 21 seconds of this animation shows a deep well with a single pipe jet system: