Abstract: Apparatus and method of operation for controlling vehicular traffic entering or leaving a secured facility. The apparatus consists of a tire-puncturing spikes assembly, movable post assemblies, ditch/cover assemblies, fixed posts, a gate arm, and a safety hose & pressure switch assembly. Tire-puncturing spikes are mounted on a rotateable shaft imbedded in the roadway that will raise or lower the spikes in conjunction with the gate arm to control traffic. Movable posts can be raised or lowered to stop or permit traffic movement. Mechanically operated ditch covers can be opened to provide impassable traps for vehicles (or tanks). A gate arm operated in conjunction with the spikes will direct vehicles to stop before reaching raised spikes. A safety pressure switch and hose assembly is located immediately downstream of the spikes assembly and will automatically activate the entire apparatus into a "failsafe" mode if a vehicle passes over the hose while the spikes are in the raised position.

Abstract: Apparatus and method of operation for removing a settled body of discrete particulate material confined within a vessel or other container. The apparatus includes a housing which supports a plurality of nozzles adapted to direct streams of water to impinge upon and form a slurry with the material as the nozzles are oscillated back-and-forth about vertical axes. A pair of the nozzles are mounted for vertical movement between raised and lowered positions. In the raised positions the water streams from the nozzles are directed downwardly by deflector plates for a sinking stage of operation, and in the lowered position the water streams clear the deflector plates for the clean-up stage of operation. Another pair of nozzles are fixed in vertical position on the housing and are disposed to direct their water streams outwardly in a horizontally direction for a material discharge stage of operation.