Monongahela River tank collapse
The Monongahela River tank collapse refers to a significant environmental disaster that occurred on January 2, 1988, when an oil storage tank at the Ashland Oil terminal in Floreffe, Pennsylvania, ruptured. This incident resulted in the release of approximately 3.9 million gallons of diesel oil, making it the worst inland oil spill in U.S. history at that time. The oil spilled over containment measures and flowed into a nearby ravine, eventually reaching the Monongahela River, particularly impacting wildlife and water quality in the region. Emergency response efforts began almost immediately but were hampered by freezing temperatures and darkness, complicating containment efforts.
The spill led to the deaths of thousands of fish and waterfowl, with estimates indicating around 11,000 fish and 2,000 waterfowl perished due to the environmental impact. Investigations revealed that a structural flaw in the tank, compounded by inadequate testing and lack of permits, led to the collapse. Ashland Oil was held responsible for the damages, incurring significant fines and cleanup costs. The event has had lasting implications, as oil spills continue to be reported along the Monongahela River, raising ongoing environmental concerns.
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Monongahela River tank collapse
THE EVENT: Collapse of an oil storage tank near the Monongahela River in Pennsylvania that resulted in a massive oil spill
DATE: January 2, 1988
When a faulty storage tank released millions of gallons of oil near the Monongahela River, creating the worst inland oil spill in US history to that date, the environmental damage included the deaths of thousands of fish and waterfowl.
In the early evening of January 2, 1988, the rupture of a storage tank at the Ashland Oil terminal in Floreffe, Pennsylvania, 40 kilometers (25 miles) southeast of Pittsburgh, released 3.9 million gallons of diesel oil. The oil spilled over a containment and flowed across a road into a ravine, and much of the oil eventually found its way into a storm leading to the Monongahela River.
Because of darkness and freezing weather, the extent of the damage was not fully recognized until the next morning, by which time nearly 750,000 gallons of oil had flowed through the into the Monongahela. Nevertheless, response efforts from a number of agencies, including the local volunteer fire department, borough police, and the Mt. Pleasant Hazardous Materials Team, began almost immediately. Within hours, a team from the Pennsylvania Emergency Management Agency (PEMA) was en route.
The first concern of those responding was to stop the flow of fuel, but darkness and cold made the operation difficult. Moreover, a strong odor of gasoline indicated an additional gas leak of unknown origin. The mixture of gasoline and diesel fuel presented a dangerous situation made even more serious by the presence of hazardous chemicals at a nearby chemical plant, and the decision was made to evacuate twelve hundred nearby residents. Emergency crews and firefighters worked throughout the night to contain the oil.
A coordinator from the US Environmental Protection Agency (EPA) arrived the following morning and discovered the condition of the river to be worse than expected, as the oil had dispersed through the water volume rather than remaining on the surface. Water intakes for communities downstream on the Monongahela and the Ohio River were shut off as a preventive measure.
Containment booms placed downstream had little effect, so deflection booms were used to move the oil to collection areas. Because of the cold temperatures, the oil formed heavy globs that could be picked up from the river edges and bottom. Over the next two months, nearly 205,000 gallons of oil, or 29 percent of the total spilled into the river, were recovered.
The damage caused to wildlife in and near the river was difficult to assess, as many species were hibernating or otherwise inactive in the winter weather. Researchers estimated that the spill killed eleven thousand fish and two thousand waterfowl.
Investigations into the cause of the collapse discovered a small flaw in the steel plates at the base of the storage tank. The tank’s forty-year-old steel had been weakened by reassembly, and the temperature was low enough to cause a brittle fracture. When the tank was filled, the resulting stress caused a crack near a weld.
Ashland Oil had not secured a written permit before constructing the tank, and the tank had not been properly tested before it was filled. The company was held liable for all damages, and it paid a federal fine of $2.25 million for violating the Clean Water Act and the Refuse Act; it also paid $11 million in cleanup costs and tens of millions more to other injured parties.
In 2023, additional oil spills were reported on the Monongahela. These spills created sheens, which are shiny patches on the water. Some of these sheens were 18 miles (29 kilometers) long. The source of these oil leaks was not immediately apparent.
Bibliography
DeRose, Christopher. "Pennsylvania DEP Investigating Oil on Monogahela River Near McKeesport." CBS News, 27 Oct. 2023, www.cbsnews.com/pittsburgh/news/oil-monongahela-river-mckeesport/. Accessed 19 July 2024.
Fingas, Merv. The Basics of Oil Spill Cleanup. 2d ed. Boca Raton, Fla.: CRC Press, 2001.
Lehr, Jay, et al. “Oil Spills and Leaks.” In Handbook of Complex Environmental Remediation Problems. New York: McGraw-Hill, 2002.
Marusic, Kristina. "Numerous Miles-Long Oil Spills Have Been Reported on One of Pittsburgh's Iconic Three Rivers." The Daily Climate, 7 Nov. 2023, www.dailyclimate.org/pittsburgh-river-oil-spill-2666171916.html. Accessed 18 July 2024.