Underground Tank Storage: Corrosion
Underground storage tanks that contain certain fuel types are subject to corrosion. It should be noted there are two types of fuels recognized by the U.S. EPA: automotive fuels from petrochemicals and "emerging fuels" like combinations of petroleum fuels, ethanol, biofuels, low sulfur diesel and gasoline and "new formulations of petroleum based fuels."
For employees who work at fuel stations, refineries and various businesses that store fuels for processing and production uses, understanding the basis of the cause of corrosion begins with knowing the chemical composition of fuels stored in USTs.
Most fuels contain distillates used to refine viscosity within the fuel's chemical compound, as well as additives. Since petroleum contains hydrocarbons, ions in metal dissolve under the pressure of chemicals stored within.
..understanding the basis of the cause of corrosion begins with knowing the chemical composition of fuels stored in USTs. Click To Tweet
Safety Training for Underground Storage Tanks. USTs require regular integrity inspections of the outer and internal walls. This is done with the use of probes, sensors and automatic tank gauges. Note that the EPA requires all UST detection equipment to be tested and calibrated to ensure accuracy of tank testing for leaks or corrosion. This equipment is used to monitor storage tank thickness and also to detect damage to the tank from corrosion. All personnel employed where USTs are located should receive Underground Storage Tank Safety Training to ensure the condition of diesel and petroleum USTs have not deteriorated appreciably as a result of corrosive contents stored in these tanks and in residual containment tanks. Safety training will also provide employees with the ability to identify detection alarms and report them should a leak resulting from tank corrosion occur. Learn to Perform Comprehensive UST Inspections for Corrosion. Comprehensive UST inspection procedures are part of safety training. This includes reviewing EPA checklists, studying effects of corrosion on materials of manufacture of USTs and how to perform bottom flatness testing using a probe with a digital caliper and testing fuel stored within for signs of corrosion. Trainees also learn how to check the level of fuels stored and note any signs of reduction in levels that may indicate corrosion is taking place. Level sensors are used for this purpose. Safety Training Study Courses. One of the most important parts of a safety training study course for USTs is to understand the link between compliance regulations and classifications of operator training. Safety training includes compiling reports on findings of UST inspections and documenting irregularities that indicate extensive levels of UST corrosion. With a broader range of knowledge of the after effects of a leak caused by corrosion, it is possible to avoid costly liability. The EPA reports that diesel fuel tends to corrode faster than other types of fuels. Ethanol also has been recorded as having corrosive properties. However, the fuel industry reduces the levels of potential corrosion through corrosion inhibitors. The ability to inhibit corrosion in fuels depends on the chemical composition, as well as the particular liquid flow regime. Safe UST Systems through Training. Becoming a UST operator requires extensive safety training. There are three classes of operator training. Class A and Class B.- Class A is intended for owners of UST sites who are most responsible for maintaining regulatory compliance.
- Class B is focused on recordkeeping and also daily UST system operations performed under compliance guidelines.
- Class C operators are trained in operation of UST and dispenser systems, as well as emergency response procedures and identifying the location of the cut-off switch, spill response and names and phone numbers of emergency contacts.
