Proper storage tank management

How to deal with environmental health and safety issues caused by storage tanks

November 2019 — Underground or aboveground tanks will present environmental health and safety issues for many facility managers sooner or later. With the increasing cost and liability associated with the cleanup of soil and groundwater contamination caused by leaks or spills, owners and managers are wise to fine-tune their storage tank operation and maintenance (O&M) activities on a regular basis.

Assessment of Current Conditions

Before an O&M schedule can be developed, it is essential for an owner or manager to answer the following two general questions:

  • Do the tanks we currently have comply with the regulations?
  • If not, what needs to be done to bring the tanks into compliance?

Most managers are aware of any above ground storage tanks (ASTs) or underground storage tanks (USTs) located on the property. However, an environmental compliance audit of the property or a Phase I or Phase II site assessment may turn up, for example, a tank that a tenant installed without permission or a tank that predates current ownership. If previously unknown USTs or ASTs are discovered during a property inspection, the manager should immediately determine the condition of the tank(s), registration/notification requirements, and applicable environmental regulations. If a tank registration not obtained, fines may be levied by the applicable state agency.

When a previously unknown UST is discovered on a property, however, it is often difficult to determine the construction, date of installation, or whether or not the tank is or has been leaking. Records may be either nonexistent or contain only partial and sometimes incorrect information. Assistance from an environmental consultant may be required to determine the condition of the UST and the surrounding soil.

In an existing building, the manager should look for and be able to find the tank registration issued by the state or local agency. Tank registrations are usually renewed annually or once every few years; however, a “found” tank may predate the regulations requiring registration. Local authorities usually indicate that registration is not required if a tank is found and it will be destroyed, if the destruction occurs within 60 days. If that period is exceeded, a pseudoregistration would be obtained until the destruction.

Sometimes UST owners or operators mistakenly think they can avoid environmental and safety requirements by changing to ASTs. However, ASTs are subject to both federal regulations and state/local regulations. Before choosing an AST option, UST owners and operators should keep in mind that USTs must be properly closed. This includes notifying the appropriate regulatory authority at least 30 days before closing the UST, conducting any necessary site assessment and remedial action, having the tank emptied and cleaned safely, and either removing the tank or leaving it buried but filled with an inactive solid, such as sand.

Some ASTs need to meet the EPA’s Spill Protection, Control, and Countermeasure (SPCC) requirements, as well as state environmental regulations. ASTs are often exposed to the risk of damage from vehicles or vandals, which can result in fire and other hazards. At a minimum, most ASTs need to meet state and local fire codes, which usually have some mix of construction, installation, and O&M requirements that are intended to prevent dangerous incidents. Check with the state agency and local authority, such as the fire marshal having jurisdiction, for information.

In assessing the status of tanks on the property, the facility manager should check whether the generator fuel supply is adequate. The generator, if there is one, should have been designed and installed to run long enough to permit evacuation of staff and tenants and the operation of critical equipment. The manager and architect/engineer should estimate exactly how long the emergency generator or boiler will need to run and install an AST just large enough to keep it in fuel that long. Many facilities require an AST of only 500 gallons or less. Keep in mind that installing an AST larger than 1,320 gallons will require you to comply with all SPCC regulations. This is a risk-assessment issue; management needs to weigh the probability of an evacuation against the facility’s size and occupancy to arrive at the optimal AST capacity to fuel a generator.

Once you have collected all the information about your facility’s tanks, underground and aboveground, and have established which (if any) do not comply with regulations, the next step is to bring them into compliance as soon as possible. If the tanks are on leased properties, close collaboration with regulators and tenants is essential to determine tenants’ contractual and regulatory responsibilities regarding them. It is the tenant’s responsibility to pay for tank upgrades or removals in the event of tenant default or departure.

Remember that federal regulations are considered minimal standards. For example, the EPA allows a leak rate of 0.2 gallons per hour from a UST. In a year, this UST will have leaked 1,753 gallons, contaminating your property and reducing its resale value. Average cleanup costs may range upward of $125,000. For this reason, it is prudent to develop O&M schedules that are more comprehensive than the ones mandated by the regulations. It is best to assume that local regulations will be more restrictive, because those agencies delve into many more details than broad EPA rules. The best place to begin the analysis of standards is with local institutions, which have the most at stake for a disruption or contamination.

Operations and Maintenance for Underground Storage Tanks

USTs are a complex collection of mechanical and electronic devices that can fail under certain conditions, even in new or recently upgraded systems. System failures can be prevented or quickly detected by following routine O&M procedures.

This article provides useful information on effective O&M procedures, but cannot address every possible UST system or all state or local regulatory requirements. Check with your state regulatory agency for information on any additional or different requirements.

Basic tank and piping O&M covers the following:

  • Automatic tanks gauges (ATGs): Use the ATG system to test for leaks at least every 30 days
  • Spill buckets: Periodically check the spill bucket to remove any debris
  • Inventory control: Record how often the generator or boiler is run during the month, and estimate the fuel usage
  • Automatic shut-off and overfill devices: A qualified UST contractor should periodically check to ensure these device functions properly
  • Cathodic protection: A qualified corrosion tester should periodically check to ensure the cathodic protection system is sufficiently protecting your UST

Operations and Maintenance for Aboveground Storage Tanks

Sometimes single-walled ASTs are provided with some type of secondary containment (for example, a dike, vault, or concrete encasement) and/or insulation. There are also concrete vault tanks, double-walled tanks (made of steel and fiberglass), diked tanks with secondary containment, and tanks with special insulating materials between the inner and outer walls. The AST may also have cathodic protection and overfill and spill equipment, as well as an ATG. All of this requires regular inspection and maintenance in order to operate properly for the life of the equipment.

For example, if a property contains transformers, the oil requires regular testing. If the facility triggers the SPCC regulations, the AST will require regular integrity testing (testing to show that the tank will not leak). ASTs with jackets (concrete or insulation) will require removal of part of the jacket to do appropriate testing, which is more expensive than testing steel tanks. Most recently constructed ASTs have a manual prepared by the manufacturer. If the manual is not available at the facility, it often can be downloaded from the Internet. The manual provides recommendations and requirements to maintain and operate the AST.

All types of ASTs and oil storage containers require regular inspections to ensure that they are functioning properly and not leaking. Managers should have maintenance staff pay particular attention to day tanks. Maintenance of day tanks—cleaning out of sediment, checking the float functionality—is often neglected. Malfunctioning day tanks may pump the associated AST (or UST) dry, causing spills to the roofs of multi-story buildings, as well as to local rivers.

Diligent O&M activities will ensure safe operation of an AST system. Product transfer operations—as described for USTs—should be closely supervised to prevent spills or overfills. Carefully and regularly maintain, check, and calibrate AST and UST equipment and the devices used perform those functions, because they can also fail.

As a facility manager (or owner) you always need to know the status of tanks on site, make sure the necessary maintenance is regularly done, and handle problems quickly and legally so they don’t compound.

This article is adapted from BOMI International’s Environmental Health and Safety Issues course, part of the RPA, FMA, and SMA designation programs. More information regarding this course or BOMI International’s new High-Performance Sustainable Buildings credential (BOMI-HP™) is available by calling 1-800-235-2664. Visit BOMI International’s website,