CSB to investigate Puerto Rico tank farm fire, blast

The US Chemical Safety Board will fully investigate an Oct. 23 tank explosion and fire at Caribbean Petroleum Refining in Puerto Rico that damaged homes and businesses more than a mile away, the board said Nov. 17.

Nick Snow
OGJ Washington Editor

WASHINGTON, DC, Nov. 17 -- The US Chemical Safety Board will fully investigate an Oct. 23 tank explosion and fire at Caribbean Petroleum Refining in Puerto Rico that damaged homes and businesses more than a mile away, the board said Nov. 17.

It said that at 12:23 a.m. on Oct. 23, a large vapor cloud ignited at the facility near San Juan that includes a refinery that was shut down in 2000 and a tank farm that is still in operation. CSB sent investigators to the site that day who have conducted interviews, requested hundreds of pages of documents, and catalogued key pieces of evidence, it said.

A tank was being filled with gasoline from a ship docked in San Juan’s harbor when the accident occurred, according to CSB. It said that investigators have determined that a likely cause was the tank’s being accidentally overfilled. Gasoline then leaked undetected and spread across the facility, creating a vapor cloud 2,000 ft in diameter until it reached an ignition source in the facility’s northwest section, it said.

It said that its investigators found that the tank’s liquid level could not be determined on the evening of the incident because the facility’s computerized level monitoring system was not fully operational and operators used a mechanical gauge on the tank’s exterior wall instead. “Therefore, as the gasoline level in the tank rose and eventually overflowed, employees located in the facility’s control room were unaware of the emergency,” CSB said.

“The filling of a tank without a functioning monitoring system is the type of activity the CSB will be examining very closely,” said Jeffrey Wanko, the investigator-in-charge. “The CSB’s investigation will examine operations particular to Caribbean Petroleum, but will also look at the regulations and best practices surrounding the industry as a whole in an effort to improve safety practices at similar facilities.”

Contact Nick Snow at nicks@pennwell.com.

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