TEXAS CITY — Phones rang out across Texas City early Sunday morning telling residents they should stay inside their homes and turn off air conditioners.
A mechanical failure at Valero’s refinery on FM197 caused the release of a plume of sulfur dioxide about 2:20 a.m.
When Texas City officials were notified of the release, they were initially told that the gas was contained to the refineries perimeter, said Derek Duckett, the city’s emergency manager.
But when emergency responders rushed to the scene, they relayed to Duckett white gas was visible and being carried by the wind outside the perimeter of the refinery facility.
Sulfur dioxide, commonly referred to as SO2, is a sour gas that smell like ammonia, Duckett said.
Exposure to it can cause a burning sensation in the nose and throat and make breathing difficult for some people, particularly asthmatics.
The release came from one of the plant’s sulfur recovery units, a device that is used to recover elemental sulfur that is removed from crude oil in the refinement process. Recovered sulfur can be used in other products, such as fertilizer.
After receiving reports from the scene of the refinery, Duckett made the decision to issue a shelter-in-place alert.
Using Texas City’s alert system, more than 22,000 phone calls were made advising people in the area of the plant to avoid going out doors.
“Any gas they release that is not normally in the air is a threat,” Duckett said. “If you breath it in, it’s probably not good for you.”
Duckett said he made the decision not to use the city’s siren system to amplify the alert.
“I know some people were upset that we didn’t use the sirens,” Duckett said, referring to some posts that were made on Texas City’s Office of Emergency Manager Facebook page.
He said there was a fear that if sirens were used, people would walk outside to confirm that they heard something and expose themselves to the substance that emergency management officials wanted residents to avoid.
Duckett said the loss of power was limited to the plant. He said initial reports made to him indicated that an equipment failure had caused the power outage.
“What they told me was there was a short in one of the wires, which caused a fuse to blow, which in turn shuts the power down,” Duckett said.
Bill Day, a Valero spokesman, said the cause of the outage was being investigated.
Day said the plant never completely lost power and that the release was caused by an “upset,” or mechanical issue at the facility.
Valero was able to repair the sulfur recovery unit and an all-clear was issued at 5:15 a.m.
No injuries or medical issues were reported in relation to the gas release or the subsequent shelter-in-place order.
The Valero Plant is Texas City’s second-largest refinery and has the ability to refine about 225,000 barrels per day of oil.
The loss of power at the Valero refinery is nothing new. The refinery has a history of power issues that often lead to increased flaring and minor releases.
Few over the years have resulted in a shelter-in-place order.
The last major power outage happened in November.
In 2011, the refinery had four major power outages and complained that Texas-New Mexico Power Co., the area’s electrical provider, needed to make fixes to its local electrical grid system.
In April 2011 all of the city’s industrial sites lost power and had to order emergency shutdowns because of issues with Texas-New Mexico Power’s grid system.
City officials issued a citywide shelter-in-place order because of the outages three years ago.
Duckett said the refinery acted responsibly by informing city of the gas release.
To sign up for Texas City’s Emergency Alert System, visit www.texas-city-tx.org/emergency_management/index.php or call 409-643-5840.