Investigation on Dewatering of a Deep Shaft in Strong Permeable Sandy Pebble Strata on the Bank of the Yellow River

Table 4

Details of pumping wells.

Well location	Quantity	Diameter (mm)	Filter length (m)	Depth of well (m)	Type of well
In area I	9	650	15	55	Steel pipe well
In area II	6	650	30	60	Steel pipe well
In area III	52	800	30	60	Cement well