A Complete Guide to Underground Storage Tanks (USTs)
A power failure in your facility can impact vital systems and make them unavailable. For hospitals, this isn’t an option.
In the event of a failure due to weather or a natural disaster, hospitals are required to have 96 hours of continuous power available. Critical systems that need to remain online include power, lighting, hot and cold water, air-handling systems, and patient support systems.
As a result, hospitals often rely on underground storage tanks (UST) to power their boilers and backup generators. The EPA defines USTs as “any underground piping connected to the tank that has at least 10% of its combined volume underground.” USTs store regulated substances such as heating oil, aviation gas, jet A fuel, diesel, kerosene, and gasoline.
Watch this short video to learn about the current trends our experts are noticing for USTs.
The Mass Tank Replacement of the 1990s
Two regulatory events in the 1990s led to the replacement of USTs with more modern counterparts:
In 1993, The Environmental Protection Agency (EPA) identified many outdated fuel systems, so they issued a mandate that all federally regulated USTs must have detection technology to alert property owners to potential fuel loss.
In 1998, a deadline required USTs to meet government requirements for spill, overfill, and corrosion protection.
These events led to thousands of UST owners replacing their tanks between 1993 and 1998. However, after 25-30 years of service, these underground storage tank systems are outside their warranties and experiencing structural, mechanical, or compliance failures. Since 2020, the drive to replace old USTs has increased and will likely continue.
Top Risks of a UST Leak
If an underground storage tank experiences failures that cause a fuel leak, the consequences can be severe. These include:
Supply Issues and Hospital Shutdowns
A leak from an underground storage tank that supplies boilers or generators to a hospital can jeopardize these mechanical systems, potentially causing a fuel shortage for critical building operations. Unless the hospital enacts immediate, interim measures, it could shut down and affect patient care.
Environmental Effects
Leaking underground storage tanks can easily contaminate nearby soil and groundwater with hazardous materials. USTs hold anywhere from 1,000 to 30,000 gallons of diesel, but even a small leak can cause widespread environmental damage that requires remediation.
Repair and Cleanup Costs
Facility owners must take corrective action to fix damaged tank systems after a release. It's an expensive project and if the spill is substantial, the cleanup can last years. It is not unusual for investigation and cleanup expenses to exceed $1 million.
Regulations
Regulatory authorities at the city, county, and state levels may intervene on-site based on the leak's seriousness. Any non-compliance could lead to fines imposed by government regulators for the leak.
Without proper detection methods in place, these leaks can go unnoticed, escalating the severity of potential harm. It is crucial for tank owners to act proactively before a fuel leak to avoid these costly outcomes.
The Benefits of Double-Walled Tanks
Since the 1990’s, manufacturers commonly make USTs from double-walled steel or fiberglass. A double-walled tank features an inner lining, so if a breach occurs, the outer shell prevents it from immediately leaking into the ground. There's also a monitoring system in the 1-2 inch interstitial space between the two liners that helps with leak detection. This airspace is equipped with sensors in the fluid, triggering an alert when the inner lining is breached.
Facilities commonly use steel tanks with a fiberglass outer shell since fiberglass is resistant to corrosion. If accidentally struck during drilling or digging, the tank is unlikely to rupture and repairs would only be necessary for the outer fiberglass layer. Although these tanks cost more upfront, they can last over 30 years.
Underground Storage Tanks (USTs) vs. Above-Ground Storage Tanks (ASTs)
Healthcare facilities can utilize either an underground or an above-ground mounted tank. Each option has its own set of advantages and disadvantages.
Underground Storage Tanks (USTs):
Pro: They don’t take up real estate above ground, which saves space.
Pro: They are protected from unauthorized people tampering with the tank.
Con: Since everything is underground, USTs are more difficult to access and repair.
Con: A leak from a UST is more likely to affect groundwater, so they are subject to greater storage tank regulations.
Above-Ground Storage Tanks (ASTs):
Pro: Since the tank is above ground, leaks are easier to find and address. By following your facility’s Spill Prevention Containment and Countermeasures (SPCC), a leak can be contained promptly.
Pro: They are more secure from a liability standpoint and are easier to repair.
Pro: There is less wear and tear because the tanks aren’t in contact with soil and groundwater.
Con: They can take up valuable real estate on the facility campus.
ASTs are a popular option for facilities, especially as property owners replace aging UST systems. The benefits of above-ground tanks lead to a longer lifespan of 40-50 years, compared to 20-25 years for an underground storage tank.
Finding Hidden USTs on Your New Property
If you're looking to purchase property that may have an existing oil tank, it's essential to identify and assess the tank before finalizing the transaction. In most real estate transactions, the lender requires a Phase I Environmental Site Assessment to be done on the property. Environmental specialists will discover any existing USTs during this assessment. They will also use historical research to see if there was ever a gas station or similar type of use on the property. If the Phase I assessment identifies an underground storage tank on the site, conducting soil sampling or records research may be necessary to investigate the tank's history and any associated issues.
Even if it is not required, we advise performing a Phase I Environmental Site Assessment to gain a comprehensive understanding of the property. It is crucial to avoid post-purchase surprises like undiscovered tanks or soil contamination issues from hazardous substances.
Closing USTs
If a UST on a property is no longer active, it cannot simply be left in the ground. Property owners need to properly close the tank to ensure it does not cause future issues.
The best option for closing an existing UST is removing the tank from the ground. Regulators typically prefer this solution since it eliminates any potential for leaks or contamination in the future. However, based on construction around a UST in the years following its installation, this is not always a safe or viable option.
Filling a UST with concrete is the next best solution because it makes the system unusable. The tradeoff is that it makes the tank heavy. A 20,000-gallon tank filled with concrete easily weighs 300 tons, so if a future facility renovation requires the tank to be removed, it’s a giant obstacle.
It is possible to fill a tank with foam instead, which is similar to a Styrofoam-like material when it dries. This option is lightweight so if the tank needs to be removed later, it won’t present a problem. However, several states do not allow this as a closure-in-place measure.
Sand was once a popular closure-in-place material, but it does not seal out water like concrete and foam. This leads to corrosion within the oil tank, which is why state regulators can restrict this option.
Planning for Replacement
If your facility’s underground storage tank is reaching the end of its warranty, proactively planning for its replacement can save you from additional costs, unexpected downtime, and regulatory complications. Here are some steps to consider:
Regular maintenance on the existing tank to avoid fuel leaks
Stay updated on current UST regulations at the local, state, and federal levels to avoid any violations
Begin budgeting for your new tank before needing to replace an old tank
GHP can help with your facility’s tasks by finding the right experts based on your system and location, pricing UST replacement costs, and being your trusted professional for any questions or issues that arise.