Correct Filling Practices for USTs

Avoiding injuries or emergencies for UST filling requires training and knowledge of filling practices and standards provided by the U.S. Environmental Protection Agency (EPA). The EPA focuses attention on operators and owners of sites where USTs are located, as well as groundwater, soil and worker safety.

Tank Integrity

The most common reason for underground storage tank (UST) leaks is tank material corrosion. This is the reason many owners of properties where underground storage tanks exist should be mindful of tank integrity testing on an annual basis.

The American Petroleum Institute (API), American Society for Testing and Materials (ASTM), National Association of Corrosion Engineers, Underwriters Laboratories (UL), Steel Tank Institute (STI), National Leak Prevention Association (NLPA), and the National Fire Protection Association (NFPA) all provide standards and codes as developing organizations for owners and operators to rely on for UST compliance resources for UST filling.

Review Design, Engineering and Manufacture

To get to the root of UST filling safety for owners and operators, it is important to understand the design, engineering and manufacture of underground storage tanks. For example, studying the actual materials of design and construction of USTs leads to a better understanding of safety.

Take Note of the Coatings

Some USTs are coated with epoxies. The manufacturer's operations and maintenance manual and SDS will provide the necessary data on the type of coating used. Epoxy is intended to separate the tank from the surrounding soil to prevent corrosion and leaks. With the motion of filling a tank, epoxy may develop small perforations in the wall of the tank.

Cathodic Protection

Note epoxy for UST coating is done electrically, thereby providing cathodic protection. In most cases, cathodic protection consists of anodes from an active type of metal linked to the UST. An anode may also create tiny holes in areas where UST epoxy coating fails.

Correct Filling Practices for USTs

Essential to training for correct filling practices for USTs is to know what the contents of the UST is or will be. For example, some USTs may be filled with oil for commercial or residential heating purposes. They may also be filled with oil for industrial processing use.

USTs may also filled with water or industrial process chemicals, pesticide manufacturing or storage purposes of industrial or commercial wastes. Leaks of these types of high capacity USTs are the reason the U.S. EPA and states require USTs to be registered. In the event of a leak, the state environmental agency and EPA should be notified immediately for safety of workers, operators and others beyond the property line where a UST is located.

Source of UST Tank Filling

The source from which UST are filled are usually transport trucks with large volume tanks attached to the cab of the truck. These are the most commonly used for filling USTs. They are designed to avoid overfilling and loss of tank integrity involved in the actual filling movements. A tank truck may have a top or bottom loading manhole with a bung seal, pressure relief, butterfly, and check valves, depending on the truck design.

When USTs are filled, the truck operator or the UST owner/operator may begin the filling process by activating the downloading gauges and tubing that is inserted into the UST inlet. Industrial UST filling is monitored or performed by owners. The onus of responsibility for tank filling rests with the owner of the tank. Due to compliance regulations and potential liability should corrosion or leaks occur due to negligence, it is clear why Underground Storage Tank training is imperative.

Tanks That Do Not Need to Conform

The EPA lists several types of tanks that do not conform to federal UST requirements. These include:

• Tanks that store heating oil on premises where storage occurs
• Flow through process tanks
• Emergency spill and overfill tanks
• Tanks 110 gallon or less capacity
• Farm and residential tanks 1,100 gallons or less capacity that hold motor fuel used "for noncommercial purposes"
• Tanks located on or above "the floor of underground areas, such as basements or tunnels"
• Septic tanks and systems for used in the collection of storm water and wastewater

The Importance of UST Filling Training

For owners and operators involved in UST filling, comprehensive training courses are available online. Underground Storage Tank Training online is a convenient way to avoid UST filling accidents and increases safety.