Patent ID: 7390142

Claim:
A storage tank access system, the storage tank access system for enabling access to underground storage, the storage tank access system being cooperatively associated with an underground system-receiving cavity, the underground system-receiving cavity being spatially located intermediate inferior backfill material and a superior surface layer, the superior surface layer comprising a superior layer surface, an inferior layer surface, and a surface layer thickness, the surface layer thickness extending intermediate the superior and inferior layer surfaces, the storage tank access system comprising, in combination: an underground storage tank assembly, the underground storage tank assembly comprising a storage tank, the storage tank comprising an outer tank surface, an inner tank surface, and a substantially circular transverse tank cross-section, the transverse tank cross-section comprising a tank radius of curvature; and an access/isolation riser assembly, the access/isolation riser assembly comprising a cylindrically-shaped access/isolation riser member, the access/isolation riser member comprising a superior riser end, an inferior riser end, an inner riser surface, an outer riser surface, a substantially uniform riser diameter, and a longitudinal riser axis, the superior riser end defining a tank access aperture, the outer riser surface at the inferior riser end comprising a plurality of paired curvilinear score indicia and first and second lateral vertices, the score indicia extending intermediate the first and second lateral vertices, the score indicia being paired based upon a plurality of angles of inclination, the angles of inclination extending intermediate the inferior riser end and the curvilinear score indicia at the first and second lateral vertices, the curvilinear score indicia enabling a user to remove paired inferior end portions from the inferior riser end, the removed paired end portions forming a tank-engaging, saddle-shaped mouth at the inferior riser end, the tank-engaging, saddle-shaped mouth comprising a vertical riser radius of curvature, the vertical riser radius of curvature being substantially equal to the tank radius of curvature, the tank-engaging, saddle-shaped mouth being engageable with the outer tank surface.