Vertical Underground Storage Tank and Method of Installing and Forming the Same

Abstract

A vertical underground storage tank that is installed and partly in-situ formed with minimized excavation, minimum footprint, and without dewatering.

I claim: 
     
         1 . A composite-material underground storage tank for storage of fluids, the tank comprising:
 an enclosed cylindrical vessel vertically oriented with one circular end at the top and the other circular end at the bottom said vessel comprising the interior surface and inner layer of said composite-material underground storage tank;   a vertical bored shaft in the ground having a diameter larger than the outside diameter of said cylindrical vessel and depth below ground of at least equal to the length of the said cylindrical vessel, said bored shaft housing the said cylindrical vessel such that the annular space between the outside perimeter of said cylindrical vessel and inside perimeter of said vertical shaft is nearly uniform around, said vertical bored shaft also serving as the formwork for the in-situ forming of the exterior layer of said underground storage tank;   in-situ poured concrete that occupies said annular space between said cylindrical vessel and said vertical bored shaft, said concrete comprising the exterior surface and the outer layer of said composite-material underground storage tank;   means of access from ground surface into the interior of said cylindrical vessel via said circular end at the top.   
     
     
         2 . The underground storage tank of  claim 1  further comprising a port near the bottom of said vessel accessed and operated from inside said cylindrical vessel fitted with a means of opening and closing said port that is operated from exterior of said cylindrical vessel at ground level. 
     
     
         3 . The underground storage tank of  claim 2  wherein the said port is further fitted with a means of establishing a sealed connection with a pressure pipe that extends horizontally out and beyond said vertical bored shaft. 
     
     
         4 . A plurality of interconnected composite-material underground storage tanks for storage of fluids, comprising:
 a plurality of enclosed cylindrical vessels vertically oriented each with one circular end at the top and the other circular end at the bottom, said vessels comprising the interior and the inner layer of said composite-material underground storage tanks;   a plurality of vertical bored shafts in the ground corresponding to said vertical vessels having diameters larger than the outside diameters of their respective said cylindrical vessels and depths below ground of at least equal to the lengths of their respective said cylindrical vessels, housing the said cylindrical vessels such that the annular spaces between the outside perimeters of said cylindrical vessels and inside perimeters of said vertical shafts are nearly uniform;   in-situ poured concrete that occupies the said annular spaces between said cylindrical vessels and said vertical bored shafts comprising the exterior surface and the outer layer of said composite-material underground storage tanks;   at least one access from ground surface into interior of said cylindrical vessels via at least one said circular end at the top of one of said vertical vessels;   at least one port on the inside of and near the bottom of each and every one of said cylindrical vessels capable of being fitted with a means of opening and closing of said ports from exterior of said cylindrical vessels at ground level plus means of establishing a sealed connection with a pressure pipe that extends horizontally out and connects to at least one of the said plurality of vessels.