Sounds like he is using a jet pump. They are designed for shallow wells. I cannot caution you enough about drinking water from that shallow a well. At 4-6 feet you are drinking what ever hits the ground. Unfortunately most wells in Alaska have sulfur tasting water. It may test out fine but the sulfur gives it an off taste, sometimes a downright terrible taste. A Brita filter pitcher does a fine job of removing the sulfur taste.
I would even be skeptical of a 20-30 foot well unless there was a layer of clay between the ground surface and where ever the well was making water. The clay serves to isolate the surface water from the subsurface water and driving casing through that clay layer allows you to draw water from the lower water zones without danger of the surface water co-mingling with the clean water.
