초록 ▼

A system for automated soil gas sampling, analysis and reporting to determine the presence and magnitude of a fluid leak from fluid storage vessels by detecting the presence of a unique and identifiable tracer chemical in the fluid leak. The system includes an array of sampling probes disposed in ea

A system for automated soil gas sampling, analysis and reporting to determine the presence and magnitude of a fluid leak from fluid storage vessels by detecting the presence of a unique and identifiable tracer chemical in the fluid leak. The system includes an array of sampling probes disposed in earthen material supporting fluid storage vessels. Each of the sampling probes is connected to a first valve selectable between individual sampling probes in the array. The first valve is connected to a second valve which communicates a gas sample from the first valve to a sample loop and loads the gas sample into the sample loop. Switching of the second valve from the first valve to a carrier gas source introduces a pressurized carrier gas into the sample loop displacing the gas sample out of the sample loop and into a gas chromatograph for analysis. A process controller governs all switching functions of the valves, actuation of the vacuum pump and the gas chromatograph in accordance with a pre-programmed instruction set. Data output by the gas chromatograph is processed to determine the presence of a tracer in the soil gas sample and actuate a signal flag indicative of the presence of the tracer chemical in the soil gas sample.

대표청구항 ▼

A leak detection method for detecting fluid leakage on a repetitive cycling monitoring basis from at least one of a plurality of fluid storage vessels, including subsurface fluid storage tanks, aboveground fluid storage tanks and fluid pipelines disposed in or on an earthen material, comprising the

A leak detection method for detecting fluid leakage on a repetitive cycling monitoring basis from at least one of a plurality of fluid storage vessels, including subsurface fluid storage tanks, aboveground fluid storage tanks and fluid pipelines disposed in or on an earthen material, comprising the steps of: (a) doping the fluid contained with the at least one of a plurality of fluid storage vessels with a chemical tracer, the tracer having a gas chromatography signature separate and distinct from the fluid and from earthen material supporting the at least one of a plurality of fluid storage vessels and capable of molecular diffusion within the earthen material in the gas phase; (b) disposing a plurality of sampling means for collecting soil gas samples, the plurality of sampling means forming an array in the earthen material in fluid flow proximity to the at least one of a plurality of fluid storage vessels, each of the plurality of sampling means having a gas conduit coupled thereto; (c) selecting a first of the plurality of sampling means; (d) evacuating a first soil gas sample from the first of the plurality of sampling means by applying a negative pressure to the first of the plurality of sampling means; (e) loading the evacuated first soil gas sample into a sample loop by applying the negative pressure through the sample loop thereby moving the first soil gas sample from the first of the plurality of sampling means into the sample loop; (f) connecting the sample loop to a gas chromatograph; (g) flowing a carrier gas into and through the sample loop, thereby displacing the evacuated first soil gas sample out of the sample loop and into the gas chromatograph; (h) analyzing the first soil gas sample in the gas chromatograph and outputting at least one data signal characterizing the soil gas sample from the gas chromatograph; (i) processing the at least one data signal characterizing the soil gas sample from the gas chromatograph and interpolating the at least one data signal from the gas chromatograph and outputting an integrated data signal containing identification data from the gas sample from the gas chromatograph to determine the presence of tracer in the soil gas sample; (j) activating a signal indicative of the detection of the tracer in the soil gas sample; and (k) repeating steps d) through j) until each of the plurality of sampling means in the array have been tested.