Abstract: A soft shell, flexible storage tank is provided, including corners of an improved configuration adapted to resist leaks. The walls of the tank and the corners are relatively more rounded and larger in radius than those of conventional flexible tanks. The walls and the improved corners act together to resist leaks. The rounded corners tend to reduce the effective pressure in the tank walls by loading the seams predominantly in shearing stress when the tank is filled with a liquid. The rounded corners are developed as panels, which are thermally bonded to produce secure and reliable liquid-tight seams. Each of the panels is bonded by lapped seams to others of the panels. Each of the rounded corners includes a generally triangular corner that is bonded to at least three other panels. In effect, the flexible storage tank functions as a pressure vessel, which tends to resist leakage.

Abstract: A containment bag for installation over a fluid control valve is provided. The valve containment bag is configured to contain leaks emanating from fluid control valves connected in line between an associated first inlet pipe and a second outlet pipe. The inlet pipe and the valve form a first junction and the outlet pipe form a second junction which are to be housed, along with the valve itself, within said bag so that fluid leaking from the junctions leaks into the containment bag. The containment bag is formed of an impermeable fabric which encloses an internal volume sufficient to accommodate the control valve and the associated junctions. The impermeable fabric defines first and second openings between the internal volume and the external environment, the first opening has a diameter substantially equal to the outer diameter of the inlet pipe, and the second opening has a diameter substantially equal to an outer diameter of the outlet pipe.

Abstract: The invention provides secondary contaiment for liquid carrying equipment which is in a confined area. The invention is especially well suited for retrofitting manholes containing pumps for underground gasoline distribution systems. The pumps or other equipment are removed to expose pipes or wires entering the manhole. Then, plates are bolted around the pipes or wires to engage and support a bag made of a material which resists the attack of the liquid. Holes are cut in the bag to pass the pipes or wires. The bag is placed in the hole, expanded to approximately fill hole, to rest on the plates, and is sealed to the plates, pipes, or wires. The top of the bag is gathered and closed to resist entry of ground water.

Abstract: A dispenser pan for collecting fluids spilled under a gasoline dispenser (pump). The pan may be installed without necessarily requiring a removal of the dispenser from its underlying supporting structure. The pan is made of a flexible membrane which may be stuffed through a hole in a cement island supporting the dispenser, worked into position, and then anchored in place. A pocket is formed on the bottom of the membrane in order to form a sump and in order to receive a shear valve on the bottom of the sump.

Abstract: A mechanically strong, airtight, watertight seam provides for joining two panels of industrial strength fabric or material. The inventive seam has two connection systems. One system is a mechanically strong structural connection which is used to make the seam as strong as the fabric panel material. A second system is an all plastic slide closure in the form of a zipper connection which overlies the structural connection, joins the panels into a single cover, and makes the seam airtight, watertight and maintenance free.

Abstract: A mechanically strong, airtight, watertight seam provides for joining two panels of industrial strength fabric or material. The inventive seam has two connection systems. One system is a mechanically strong structural connection which is used to make the seam as strong as the fabric panel material. A second system is an all plastic slide closure in the form of a zipper connection which overlies the structural connection, joins the panels into a single cover, and makes the seam airtight, watertight and maintenance free.

Abstract: The invention process for installing an overliner membrane begins with preparing a site by digging a pit for the installation of fuel tanks, for example, which may be associated with leakage or spillage of fluids. Then, ballast is packed under and around the tanks to support and stabilize their position, the ballast rising to a level which is above the tanks but below points where the leakage or spillage may occur. Next, a frame is built over the ballast in the area where the leakage or spillage may occur. A membrane is spread across the surface of the ballast and attached to the frame in order to form a basin in which this leakage or spillage may collect. The frame and the membrane are completely covered with ballast in a manner which maintains the side walls of the membrane in a vertical position. A trench system for delivery pipes carrying fuel from the tank to outlying locations contains a trench liner membrane which surrounds the pipes and drains into the membrane basin.

Abstract: A secondary containment system which may be manufactured in a factory, shipped and installed in a reasonably low cost and fully usable manner. In one embodiment, a large membrane of material, completely lines a collection and containment pit along with radiating trenches which drain into the collection pit. There is substantial amount of membrane bulk which enables it to bunch in the corners and to provide slack which conforms to irregularities on the earthen walls and floor of the pit. Thus, localized stresses do not occur at places where the membrane bridges protections formed on the walls, in the corners, or the like. In another embodiment, the membrane covers a tank in the pit and drapes down to form deep areas where liquids may collect. A perimeter steel cable surrounds the hole. The membrane is attached to this cable so that the membrane is mechanically strong enough to meet the shoring requirements of the various occupational safety laws.

Abstract: A mechanically strong, airtight, watertight seam provides for joining two panels of industrial strength fabric or material. The inventive seam has two connection systems. One system is a mechanically strong structural connection which is used to make the seam as strong as the fabric panel material. A second system is an all plastic slide closure in the form of a zipper connection which overlies the structural connection, joins the panels into a single cover, and makes the seam airtight, watertight and maintenance free.