Abstract: A system for inventory reconciliation and leak detection of particular utility in liquid storage tanks such as the terminal facilities that are used for the storage and distribution of gasoline. The system has the ability to monitor the inventory of several different liquid products on hand at such a facility, account for product deliveries and product dispensations (e.g., to tank trucks which deliver the product from the terminal facility to a gasoline service station), and to continually check the volume of each product dispensed against the inventory on hand so as to provide a real-time system for detecting leaks from the tanks containing each product, losses due to evaporation, volume discrepancies from flow meters which are out of calibration, and other irregularities.

Abstract: Apparatus for confirming the presence or absence of leaks in a liquid storage container, particularly in partially filled underground storage tanks, subjected to partial vacuum for the purpose of testing the tank for the presence of a leak in the area above the liquid using a hydrophone or microphone either positioned in or attached to the container to detect the sound produced by the ingress of fluid into the container as a result of the vacuum. The ingress of fluid is confirmed by recording and observing the vacuum pump on/off cycles that define a time period for the system to change from a high vacuum state at a first predetermined pressure toward a low vacuum state at a second predetermined pressure, with the pump operated to restore tank vacuum level at the end of each period back to the first predetermined pressure, such observed trends of the measured patterns in the on/off cycles for a leaking container being distinguishable from the on/off cycles for a non-leaking container.

Abstract: Method and apparatus for continuously monitoring the volume of liquid in an underground storage tank and producing data for reconciling volume with throughput. This invention provides a set of algorithms and hardware which allows the loss of product caused by equipment failure or pilferage to be determined in one day or less. In order to accomplish this task this system requires a mechanism in each tank which is capable of indicating liquid depth and temperature to a very high degree of accuracy, a water table indicator, data collection equipment for the dispenser metering system, a local computer system for calculating several algorithms and a second computer, either local or remote, which calculates the daily reconciliation and finds the source of any indicated errors. This second computer also provides reports to the tank operator and activates an alarm system in case there is a loss due to a leak in any part of the tank system.

Abstract: A method and apparatus for detecting and localizing a leak from an above-ground liquid storage tank is disclosed. The invention utilizes a fiber optic chemical sensor to sense vapor from the liquid stored in the tank through a plurality of horizontal bores created at spaced intervals through the strata underneath the tank. Each of the plurality of horizontal bores is connected to a vacuum pump and manifold system which delivers the vapor or liquid present in the strata underneath the tank, resulting from diffusion or leakage in the tank, to the fiber optic chemical sensor. The horizontal bores are created with the use of a pilot which protects the bottom of the tank from punctures and ensures that the bores lie in close proximity to the bottom of the tank, enabling the detection of leaks in the tank as they develop.

Abstract: The apparatus of the invention is a water level probe comprised of a probe body, a sleeve having openings permitting fluid flow and encasing part of a magnetostrictive sensor, and an external housing encasing electronic circuitry for processing and transmitting the electric signal generated by the magnetostrictive sensor and sealing the circuitry from fluids. The sensor comprises a float slidably mounted on a rod, the float designed to float in water but sink in a petroleum product, thereby ensuring that it will float at the interface between the water and the product. The water level probe is used in the method of the invention to measure the depth of the water in a vessel storing hydrocarbon product at predetermined time intervals. The longitudinal angle of inclination of the vessel with respect of the horizon having previously been determined, the volume of water in the vessel is calculated from the depth measurements.

Abstract: A method and apparatus for detecting and localizing a leak from an above-ground liquid storage tank is disclosed. The invention utilizes a fiber optic chemical sensor to sense vapor from the liquid stored in the tank through a plurality of horizontal bores created at spaced intervals through the strata underneath the tank. Each of the plurality of horizontal bores is connected to a vacuum pump and manifold system which delivers the vapor or liquid present in the strata underneath the tank, resulting from diffusion or leakage in the tank, to the fiber optic chemical sensor. The horizontal bores are created with the use of a pilot which protects the bottom of the tank from punctures and ensures that the bores lie in close proximity to the bottom of the tank, enabling the detection of leaks in the tank as they develop.

Abstract: Method of confirming the presence or absence of leaks in a liquid storage container, particularly in partially filled underground storage tanks, subjected to partial vacuum for the purpose of testing the tank for the presence of a leak in the area above the liquid using a hydrophone or microphone either positioned in or attached to the container to detect the sound produced by the ingress of fluid into the container as a result of the vacuum. The ingress of fluid is confirmed by recording and observing the vacuum pump on/off cycles, the on/off cycles for a leaking container being distinguishable from the on/off cycles for a non-leaking container.

Abstract: A striker plate for protecting the bottom surface of an underground storage tank from damage caused by the impact of an object thereon. The striker plate is formed by a plurality of slats having a resilient strip crossing the slats to which the slats are mounted to align the slats in side-by-side fashion and to bias the slats to a first position in which the plate is flat for application to the bottom surface of an under ground storage tank. A pivot is adapted for mounting to a setting tool so that the slats can be rolled into a cylinder for insertion through the filler pipe of the storage tank and then pivoted for application to the bottom surface of the tank and a releasable mount on the plate is provided for removing the pivot from the plate once the plate is applied to the bottom of the tank.

Abstract: A method for testing vapor recovery units having phase II capabilities for integrity, blockage, or both is disclosed. The vapor recovery unit is modified for vacuum testing. To test the integrity of the unit, a vacuum is drawn in the unit to a predetermined level whereupon it is monitored for decay over a predetermined period of time to ascertain whether the unit is leaking. To test for blockage, a vacuum is continuously drawn in the unit while the lines associated with the phase II capabilities are disconnected from the dispensing station at the point most proximal to the station. Flow of fluid induced by the vacuum is then measured and compared to the desired rate of flow to ascertain the extent of blockage, if any.

Abstract: An apparatus and method for employing the apparatus in testing underground fluid containing lines for leaks. The apparatus comprises (a) a differential pressure transducer mounted to a reservoir for indicating volumetric change in the reservoir; (b) a temperature transducer mounted in the reservoir for monitoring temperature fluctuation in the reservoir; (c) a gauge pressure transducer mounted in the reservoir; (d) a remote temperature sensor and a data acquisition and processing system. The method for employing the apparatus comprises of connecting the apparatus to the line under test and entering certain parameters of a line under test and product temperature into the test computer. The test system then monitors volumetric change in the reservoir as well as pressure and temperature fluctuations in the line under test at 30 second intervals. At the end of the predetermined test period, the system calculates the leak rate during each five minute interval of the test as well as a cumulative leak rate.

Abstract: A water level sensing probe having a probe body (24), a protective sleeve (28), and an external housing (26) is disclosed. The body contains a detector board (40) that partially protrudes from its bottom and a logic board (42) that partially protrudes from its top. The detector board senses the level of electrically conductive fluid and transmits an indication of that level to the logic board that controls the operation and partially processes the data in response to commands received through a cable (28). The detector board is protected by the protective sleeve (28) while the logic board is enclosed in the external housing (26). The probe is used by positioning on the bottom of a fluid containing tank or other vessel. Water at the bottom of the tank forms a bridging contact between a ground plane and a number of traces on the detector board proportional to the level of the water.

Abstract: Apparatus for sensing the deviation of an underground storage tank from level which is conveniently referred to as a tank inclinometer. The apparatus, or inclinometer, includes an elongate member having a feeler bar mounted to the end thereof which is aligned with the elongate members for insertion through the restricted opening of the fill neck of an underground storage tank and then pivoted to a position such that, when the elongate members are pulled upwardly, the feeler bar contacts the inside top surface of the underground storage tank. Deviations of the top surface of the tank from level are sensed and an output provided by which the deviation is observed by the operator.

Abstract: Apparatus for testing a diaphragm or piston-type pressure-actuated detector of leaks in a hose, pipe, or other conduit. Fluid at a selected pressure is introduced into a manifold through the leak detector being tested, and the manifold is provided with a plurality of flow restrictors which allow flow at a selected rate at a selected pressure. In this manner, a leak detector which allows flow at a rate higher than a selected pressure can be rejected as not functioning properly. Further, the flow rate through that detector can also be tested at a given pressure. The apparatus is also capable of operating off of pressure developed by a submerged pump for testing the leak detector without removal of the leak detector from the submerged pump.