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How Common are Petroleum Leaks from USTs?

One of the most frequent environmental concerns associated with commercial or industrial properties is the presence of petroleum underground storage tanks (USTs).  Leaks and spills of petroleum fuels (primarily gasoline and fuel oil) from USTs are the cause of the vast majority of groundwater contamination cases throughout the United States.  Because of the likelihood of leaks, if a petroleum UST has been used on a property, the assumption is generally made that some degree of soil or groundwater contamination exists.

Why Do UST Systems Leak So Often?

UST systems are comprised of the storage tanks and attached piping and dispensers.  Until the early 1980s, most UST systems were constructed of bare steel that were highly vulnerable to corrosion.  Although the tanks often leaked as a result of rust, more common sources of fuel releases included faulty piping connections and spillage into leaky fill ports during fuel deliveries.  As the result of increasingly strict state and federal UST regulations that began in 1985, dramatic improvements have been made to UST system materials, installation methods, leak-detection equipment, and system operation.  The result is far fewer cases of new spills and leaks. Despite the improvements, many thousands of undiscovered historical UST spills and leaks are believed to remain today.

How Are USTs Regulated?

Most states have an environmental regulatory agency that is charged with enforcing rules that apply to the installation and operation of regulated UST systems.  The rules are generally enforced through inspections by government officials to assure the proper use of spill prevention and leak-detection systems.  The most common non-regulated categories of USTs include heating oil tanks, industrial process tanks, and fuel storage tanks that were out-of-operation prior to 1974.

What If I am Responsible for a Spill or Leak from a Petroleum UST?

Each state has a regulatory agency that oversees the operation of a UST Clean-Up Trust Fund.  These funds provide varying degrees of financial and civil liability protections to parties responsible for soil and groundwater contamination as a result of UST system spills and leaks. 

In 1988, the State of South Carolina created a fund that serves as a “safety net” for UST owners and operators responsible for soil and groundwater contamination from USTs used for motor vehicle fuel storage.  The State administers the disbursement of monies from this fund known as the State Underground Petroleum Environmental Response Bank (SUPERB) Fund.   SUPERB is primarily funded by a 0.5 cent per gallon State gasoline tax that generates over $1 million per month for the assessment and clean-up of contamination caused by leaking USTs.  All State-mandated and pre-approved assessment and clean-up costs are paid by the SUPERB Fund after a qualified responsible party pays a deductible of $25,000 per release.  The Fund also includes third-party liability coverage for costs associated with claims of property damage or devaluation as the result of contamination caused by UST spills and leaks.



Disclaimer:  This sheet has been prepared by EnviroSouth, Inc. for general informational purposes only. The contents of this publication shall not be construed as legal or professional advice. Readers should consult an environmental professional before acting on the provided information..