Driven well Hand or air hammer Silt, sand, gravel <2 in 5 15 50 1 3/4 4 X X 3 40 Limited to shallow water table, no large gravel. Jetted well Light, portable rig Silt, sand, gravel <1 in 5 15 50 1 3/4 24 X X X X X 3 3,000 Limited to shallow water table, no large gravel. Drilled well Cable tool Unconsolidated and consolidated mediumWeb