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Then and Now: The History of Storage Tank Systems


The means to store hazardous liquids significantly changed since August 1859, when the first oil well gusher erupted in a small town in Titusville, Pennsylvania. The visionaries who funded and developed the oilrig and drill firmly believed that “rock oil” would provide an excellent source of energy for illuminating buildings. It did so for several years, but not until Thomas Edison found a way to harness electricity during the early 1880s. Fortunately for the oil industry, other innovators in the United States and in Europe have already made the first steps toward redefining transportation by developing a four-stroke engine and adapting the motor to power a vehicle.

The automotive industry was a growth industry that continued to advance further, with no signs of slowing down. From that point on, a new need for storing petroleum products grew. The first service stations required only a small tank storage capacity. At the time, it was common for products to be stored within the dispenser itself. As the demand for hydrocarbons increased, the ability to store the products safely became a vital growth factor for the fuel and automotive industries.

The storage tank industry traces its early beginnings to these events that forever altered society…

The Past
America’s use of steel tanks to store petroleum and chemicals is a microcosm of the efforts in other countries. The story of that experience covers the earliest days of discovering how oil could change society for the better; and more recent times as environmental awareness and public safety issues gave way to the compelling need to store the energy source safely.

Come the Industrial Age, and people discovered more and more uses for petroleum. Oil companies had to find the most effective means of storing the energy source. In the distant past, wooden barrels served as storage vessels. But soon enough, petroleum producers and suppliers realized that they needed a more reliable, long-term, larger-capacity solution.

During the last two decades of the 1800s, wooden barrels were replaced by riveted steel tanks to store petroleum as well as liquid chemical products. Whether it was used aboveground or underground, these riveted tanks became the standard for storage when the required capacity was beyond a few barrels.

Tank Standardization
In the early 1900s, the United States developed codes to regulate flammable and combustible liquids, and standards for performance testing and construction. The goal of standardizing tanks appealed tank owners, manufacturers, fire officials and insurers in the country. Some organizations with a stake in the manufacture and use of tanks began to address issues regarding oil storage safety.

An association of Midwestern tank and boiler fabricators – which later became the Steel Tank Institute (STI) – was established in 1916. During the same time, a third-party testing laboratory – Underwriters Laboratories (UL) – developed its first safety standards for atmospheric steel storage tanks.

Another standard critical to the growth of the storage tank industry preceded the UL developments. Around 1904, the National Board of Fire Underwriters issued NBFU 30, which, as its title states, covered “rules and requirements for the construction and installation of systems for storing 250 gallons or less of liquids which, at ordinary temperatures, give off inflammable vapors, as recommended by its committee of consulting engineers.”

Eventually, NBFU’s codes and standards became the responsibility of the National Fire Protection Association (NFPA), which revised the storage system standard’s code designation to NFPA 30L, in 1913. It is what we now know as NFPA 30, or the Flammable and Combustible Liquids Code – a document that was first published in 1957.

As the use of petroleum products increased, hydrocarbon producers and companies that install tanks soon created their own associations. In 1919, the American Petroleum Institute (API) was formed and the Petroleum Equipment Institute (PEI) was founded in 1951. Both groups have developed several important storage tank system standards and guidelines that are widely respected in many countries.

Urbanization and Industrialization
As the automobile industry began to grow, petroleum dealers had to adapt their practices to enable mass distribution. This led to the construction of the first service stations in the US – facilities that required minimal storage tank capacity.
For safety reasons and aesthetic purposes, most of the fuel tanks were installed underground, particularly at public retail service stations. This also allowed business owners to use real estates for other, more productive purposes. The burial of USTS also eliminated concerns regarding vehicular accidents or other damage that could result in fuel spill.

Advent of Welding
During the early days of steel tank production, riveting was the most common method of joining steel. In the 1920s and 1930s, many steel fabricators turned to arc welding, which led to higher quality tanks. Galvanized steel sheet was often used in the production of tanks but when World War II struck, the US had seen a shortage of galvanized products. Recognizing the scarcity, UL began to allow the manufacture of tanks using black carbon steel.
The basic cylindrical design remained unchanged for several decades but in the mid-1950s, product innovations began to surface. STI advocated placing the product line on the bottom of a heating oil tank to prevent water accumulation. This design carried the water with the heating oil to the burner, leading to evaporation.
In 1956, STI issued its Midwest 56 Standard, a widely-recognized method to designing the size and location of opening along the top of an underground storage tank.

The Anti-Corrosion Sentiment
Corrosion control on underground storage tanks relied heavily on standards development, especially in the US. For the past 30 years, tank fabricators have remarkably prolonged the expected and actual service life of steel tanks.

Between 1960 and 1970, issues concerning lost inventory became a driving force to prevent underground steel storage tanks from corroding. The ‘60s gave rise to a new material and new designs for underground flammable and combustible liquid tanks. The first design breakthrough was a non-metallic tank.

The steel industry concentrated on producing these non-metallic tanks, as did major oil producers. So, steel tank manufacturers responded with their own research efforts by focusing on methods to make steel tanks resistant to corrosion.

Shop-fabricated steel tanks were built with various forms of corrosion protection design through the use of plastic wraps or “baggies”, thick fiberglass reinforced coatings, and galvanic anodes in conjunction with coal-tar epoxy coatings. Many existing non-protected steel tanks were also upgraded in situ with internal linings and impressed-current design to protect complete bare steel systems.

Environmental and Fire Safety Awareness
Throughout the early 1970s, a strong concern for the environment led to technological advancements concerning safe storage of hazardous liquids underground.

Secondary containment is one desirable feature in tank design. Steel tanks were built with a second steel wall or with a non-metallic jacket made of FRP of HDPE. Thick urethane or FRP-coated tanks are popular without anodes. Over 250,000 sti-P3 cathodic protected tanks have been installed in the US alone since the late 1960s.

The Present
Today, the tank industry has experienced further revolutionary change. The last decade saw the emergence of many new UST system technologies and trends. Tank fabricators and system designers laid out UST enhancements in advance of the December 22, 1998 EPA deadline for upgrading underground tank systems.

A lot of small service station operators used the federal regulatory deadline as a reason to sell or shut down their fuelling facilities. Some tank owners, however, were quite receptive to the new designs because their businesses were committed to using underground storage for the long haul.

An increasing number of tank owners also revisited the question of why petroleum and chemicals had to be stored underground. The 1990s gave way to a completely new and unexpected trend – an extraordinary demand for aboveground storage tanks. Because of the negative connotations regarding expensive UST clean-ups – including contaminated soils and water resources – tank owners began to weigh down the pros and cons of owning an underground tank system. Many chose to close their tanks. For those who needed tanks for fuelling vehicles, they began sending their drivers to a nearby retail service station.

AST’s Market Impact

Tank owners began to study the advantages of an aboveground tank system. First, it is simple, cheap, convenient and trustworthy in terms of visual release detection. Second, the operator did not have to meet financial responsibility requirements of regulated UST systems. Third, the operator can eliminate problems regarding regulated, expensive soil clean-ups, which seemed to be constantly scrutinized by the public via local and national headlines. Lastly, many operators felt that aboveground tank systems were cheaper to install and less regulated – though this perception was often flawed. This new era of aboveground tanks was about to change the market.

However, the issue wasn’t as simple as how to switch from underground to aboveground. Many local jurisdictions, particularly in the US, did not allow aboveground tank systems. They followed various national fire codes that imposed restrictions upon ASTs, or simply prohibited fuel storage aboveground for dispensing automobiles. Despite this, fleet owners and industrial companies saw tremendous benefits from owning ASTs.

The typical owner of a public-accessible retail service station continued to prefer underground storage tanks over often-unsightly and potentially hazardous aboveground tanks, as did most fire inspectors.

Photo courtesy of DaveCrosby

Fire Code Revisions and Harmonization
With the sudden increase in demand for aboveground tanks, fire safety and environmental codes needed to find a way to allow the safe sitting of aboveground fuelling facilities at service stations.

Major provisions were added to the codes in early ‘90s. As the fire codes proposed new language, environmental regulators also examined what would constitute safe operation of aboveground tanks. One such federal proposal called for ASTs to employ containment that would be impermeable for 3 days. As such ideas surfaced for the first time, the shop-fabricated AST market saw a major change in customer demand. Tank operators were asking for steel dikes or tubs within which a tank would be installed. Steel, an impermeable material, met the requirements of the federal proposal. There was also an increased demand for integral double-wall ASTs.

By 1997, STI developed a statistically valid database of insulated protected tanks and double-wall F921 tanks. These insulated tanks were called Fireguard – the specification for which was published in 1994. Less than 4% of these ASTs were installed in public retail service outlets. Private fleet facilities were the primary and dominant users of these tanks for fuelling vehicles. Nearly two-thirds of stored product applications were for less flammable Class II or III liquids like diesel, kerosene and lube oils.

Despite the many significant changes in national codes, especially regarding ASTs, new proposals continue to surface every year. STI expects more revisions as regulators monitor the safety performance of aboveground tank systems within their areas.

The market-driven developments of the last 3 decades have redefined the industries that, for many years made – and used – tanks the same way, day after day. Looking back and looking forward, it’s quite evident that we have come a long way from the wooden barrels and wash basins of Titusville. But improvements are still on the horizon.

TNphoto Tatsuya Nakagawa
Tatsuya Nakagawa is the VP of Marketing and co-founder of Castagra Products, a storage tank and wastewater coatings manufacturing company that is highly acclaimed for its sustainable coatings, cold weather tank coating applications, and its durable frac tank coatings. Castagra is used by the world’s top oil and gas field services companies.