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William Walter Bohnhoff: Subsurface fluid drainage and storage systems. Invisible Structures, December 15, 1998: US05848856 (69 worldwide citation)

There is provided by the invention a subsurface drainage system which promotes efficient and controlled subsurface drainage of fluids, such as irrigation water, applied to the surface of land such as a football field. A drain core apparatus is provided that provides rapid infiltration and later move ...


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William Walter Bohnhoff: Subsurface fluid drainage and storage systems. Invisible Structures, August 1, 2000: US06095718 (48 worldwide citation)

There is provided by the invention a subsurface drainage system which promotes efficient and controlled subsurface drainage of fluids, such as irrigation water, applied to the surface of land such as a football field. A drain core apparatus is provided that provides rapid infiltration and later move ...


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Bohnoff William W: System for collecting fluids. Invisible Structures, December 29, 1999: EP0966571-A1

There is provided by the invention a subsurface drainage system which promotes efficient and controlled subsurface drainage of fluids, such as irrigation water, applied to the surface of land such as a football field. A drain core apparatus is provided that provides rapid infiltration and later move ...


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Bohnhoff William W: Systemes de drainage et de stockage souterrains de fluides, Subsurface fluid drainage and storage systems. Invisible Structures, Invisible Structures, BORDEN LADNER GERVAIS, August 13, 1998: CA2286336

A subsurface drainage system (20) for promoting efficient and controlled subsurface drainage of fluids. A drain core (22) is provided that provides rapid infiltration and later movement of subsurface fluids, but which is resistant to settling, compacting and crushing. The drain core (22) is a thermo ...


5
Bohnhoff William W: Systemes de drainage et de stockage souterrains de fluides, Subsurface fluid drainage and storage systems. Invisible Structures, Invisible Structures, BORDEN LADNER GERVAIS, April 24, 2007: CA2531826

A subsurface drainage system for promoting efficient and controlled subsurface drainage of fluids. A drain core is provided that provides rapid infiltration and later movement of subsurface fluids, but which is resistant to settling, compacting and crushing. The drain core is a thermoplastic mat hav ...


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Bohnoff William W: Subsurface fluid drainage and storage systems. Invisible Structures, PURCELL Robert E, August 13, 1998: WO/1998/035106

A subsurface drainage system (20) for promoting efficient and controlled subsurface drainage of fluids. A drain core (22) is provided that provides rapid infiltration and later movement of subsurface fluids, but which is resistant to settling, compacting and crushing. The drain core (22) is a thermo ...


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