Abstract: An improved, simplified and less expensive apparatus and method for cleaning wells embodies an elongated tube of combustible material, sealed at its ends, that is ignited at one end to generate a pressure wave that travels along the length of the tube. Outwardly directed pressure generated within the well casing by the deflagration is periodically attenuated at spaced locations along the length of the tube by a plurality of spaced short, steel sleeves circumscribing the tube and secured thereto. Three such tube sections are provided, each with its spaced, short circumscribing steel sleeves and each ignited in a selected chronological and positional sequence by three individual simultaneously electrically activated detonator caps which are provided with mutually different delay times.