Giant ITC tank farm fire caused by failed circulation pump – US CSB

HOUSTON (ICIS)–A failed circulation pump caused a giant 2019 fire at a tank farm on the Houston Ship Channel owned by Intercontinental Terminals Co (ITC), disrupting shipping along the critical waterway of one of the nation’s major refining, petrochemical and energy hubs, according to a final report of the accident.

The fire also destroyed the 15 tanks, causing property damage exceeding $150m, according to the US Chemical Safety Board (CSB), which issued the final report.

The fire had started on 17 March 2019 at Tank 80-8, an 80,000 bbl above-ground atmospheric storage tank that held a blend of naphtha and butane. The fire spread to the other 14 tanks and burned for three days.

The fire caused a breach in the containment wall, releasing 470,000-523,000 bbl of hydrocarbons and petrochemicals as well as firefighting foam and contaminated water.

A seven-mile (11km) stretch of the Houston Ship Channel was shut. The restrictions on the channel persisted for a month, disrupting chemical markets and causing some producers to declare force majeure.

The fire did not cause any injuries or deaths.

The fire was caused by a failed circulation pump at Tank 80-8, which led to the release of butane-enriched naphtha vapour. The CSB report noted an absence of a flammable gas detection system, which would have alerted the operators about the release of the vapour.

Instead, the leak continued for 30 minutes before the vapour ignited, causing the fire.

In addition, the CSB report noted the absence remotely operated emergency isolation valves. Such valves could have secured the flammable liquids in Tank 80-8 and the surrounding tanks.

The report also found problems with the design of the tank farm, which contributed to the severity of the fire. Those shortcomings include the spacing, subdivisions, the drainage system and the location of the engineering controls for the pumps. Those controls were placed inside of the containment area.

The report found shortcomings in US safety and environmental regulations. Atmospheric storage tanks are exempt from the process safety management (PSM) standard of the Occupational Safety and Health Administration (OSHA).

Because of that exemption, ITC did not have to develop a formal PSM programme for Tank 80-8. Such a programme could have developed a process that, in turn, could have found the equipment failures that caused the fire.

Also, the report flagged the flammability exemption in the risk management program (RMP) of the Environmental Protection Agency (EPA).

The owner of ITC, Mitsui & Co, acknowledged the final report and its findings. Mitsui & Co referred other questions to ITC.

In a statement, ITC noted that it has long made instrumentation upgrades and other projects at the terminal that improve the site’s ability to respond to emergencies, including those concerning safety and the environment.

Many upgrades are already completed, ITC said. Others are well underway. The company will continue to review the report and work with all regulators that investigated the accident.

“ITC is committed to maintaining a safe and operationally effective workplace,” the company said. “All of our people work hard every day to maintain good environmental stewardship and to protect our local community.”

The CSB is an independent federal agency that conducts investigations on chemical accidents. Its board does not issue citations or fines, but does make safety recommendations to companies, industry organisations, labour groups and regulators.

(adds comments from Mitsui & Co, paragraph 14)
(adds comments from ITC, paragraph 15-17)