Abstract: Methods and apparatuses for detecting leakage of hydrocarbons from and preventing corrosion of underground storage tanks. Soil samples near an underground storage tank are taken and analyzed in the field, preferably using hexane as a solvent to detect the presence of hydrocarbons such as heating and waste oil. The soil-to-tank potential of the tank and the presence of water within the tank are measured and, if warranted, cathodic protection provided to the tank to prevent corrosion or further corrosion.

Abstract: A fluid detector that senses fluids, activates an alarm and preserves a sample of the fluid for laboratory or on-site testing. The fluid detector includes a first container having a sealable cap and a fluid-passing portion, a second container disposable within the first container for collecting and storing a sample of the fluid. The detector can contain a fluid-responsive material which undergoes a change upon contact with the fluid. The change in the fluid-responsive material causes the second container to be sealed. The second container can contain a fluid collector so that the fluid can be analyzed.

Abstract: A method for testing and treating distillate fuel being stored for long periods of time for emergency power generation applications and the like, including measuring the percent transmittance of a fuel sample with ultraviolet before and after heating at a preselected temperature below the boiling range of the distillate fuel for a sufficient period of time to accelerate polymerization where the sample is made to reach such preselected temperature within about five minutes; and comparing the percent transmittance measurements to determine the suitability of the fuel for continued storage with or without the addition of further polymerization inhibitors and/or depolymerizers.