Chemical Safety Board: Regs needed to prevent catastrophic fertilizer tank collapse (5/28)
On November 12, 2008, an aboveground storage tank catastrophically failed releasing two million gallons of liquid urea ammonium nitrate (UAN) fertilizer and seriously injuring two workers. The release overtopped a containment dike and flooded sections of a nearby residential neighborhood, requiring remediation of the soil. At least 200,000 gallons of spilled fertilizer could not be accounted for, and some reached the nearby Elizabeth River, which flows into the Chesapeake Bay.
CSB Board Member William Wark said, “By recommending regulation of similar storage tanks located on the Elizabeth River, we hope to protect not only communities and workers but also the vitality of the Chesapeake watershed.”
CSB investigators found that the tank involved in the accident – referred to as Tank 201 – had undergone welding work. Contractors removed the vertical riveted seams and replaced them with horizontal welded plates with the intent of strengthening the joints. Similar work was done to three other tanks at the facility.
“The CSB’s investigation found that the welding performed on the tanks did not conform with recommended industry practices,” said Supervisory Investigator Robert Hall. “Additionally the company did not ensure that post welding inspections were conducted prior to refilling the tank to its maximum capacity.”
The report noted that the U.S. Environmental Protection Agency regulates the safety of petroleum storage tanks, but liquid fertilizer and other non-petroleum tanks are regulated by individual states. Virginia is one of 33 states that do not currently have regulations for liquid fertilizer tanks, the CSB said.
In addition to calling for state action to regulate storage tanks, the Board urged the EPA to revise and reissue a safety bulletin on liquid fertilizer tank hazards and asked The Fertilizer Institute (TFI), a trade association, to urge member companies to require appropriate inspections of tanks used to store liquid fertilizer at terminal facilities.
In December 2008, the board issued an urgent recommendation calling on Allied Terminals to take immediate action to reduce the risk of a catastrophic failure of three tanks located at its facility - one about 250 feet from the South Hill Neighborhood. The CSB also recommended that Allied Terminals select an independent engineering firm to evaluate the specified tanks and within 30 days provide a report prepared by the independent tank engineering firm to the City of Chesapeake. The independent report resulted in Allied Terminals significantly reducing the maximum liquid levels of the remaining tanks.
The CSB investigation identified 16 other tank failures at nine facilities in other states between 1995 and 2008. These 16 failures resulted in one death, four hospitalizations, one community evacuation, and two releases into waterways.