06470605 is referenced by 42 patents.

A reduction system using water pressure and vacuum excavation and including a water supply tank, water pump, vacuum pump, slurry collection tank, a system for tilting the collection tank, handheld reduction tool, and a drive system. The reduction tool, or wand, is used to deliver high pressure fluid, such as water, to the ground in order to loosen soil directly in front of the tool. The tool includes diametrically opposed nozzles which are angled with respect to one another such that pressurized water delivered from the nozzles is directed in a fashion to slice the ground in a generally spiral or helical fashion as the tool is pressed downward into the ground. As the soil is loosened by the pressurized water delivered from the nozzles, the loosened soil is sucked away to form a hole in the ground, and such loosened soil (a slurry when mixed with the water) passes upwardly through the tool in a vacuum air-flow created by the vacuum pump and is deposited in the slurry collection tank.

Title
Earth reduction tool
Application Number
9/714609
Publication Number
6470605 (B1)
Application Date
November 16, 2000
Publication Date
October 29, 2002
Inventor
Edward Kennedy
22460 SE. 216th Pl., Maple Valley
WA, US
John William Gilman
305 Water Mill Rd., Greer
SC, US
Agent
Leatherwood Walker Todd & Mann P C
US
IPC
E02F 3/88
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