a method and apparatus for sequence control of vertical movement of slurried particulates from a lower level to the upper levels , more particularly a vertical hoist system for movement of slurry from a subterranean mine area upward through an earthen or cased borehole to a surface station . the vertical pump system includes series - connected pumps having variable speed capability to transport slurry particulate from an underground sump upward to a surface surge tank or other repository . the logic sequence system exercises control over valving sequence between the underground pumps and the vertical borehole in order to control slurry surges during start - up , shut - down and emergency dump operations . thus , the pump input to the vertical conduit utilizes energy dissipator units as selectively controlled by automated block and by - pass valves to control flow of fluids from the pumps upward through the vertical conduit . selective control of the dissipator units and valving enable critical start - up , shut - down and the emergency shut - down operations and this is effected by particular sequence control .