CORPUS CHRISTI - A rare power outage at the MarkWest Javelina plant Saturday led to a backup of offgasses at each of the three refineries that feed it, causing simultaneous flaring at all the local plants about 11:20 a.m.
Flaring at the Javelina plant continued for about three hours, burning all the gas already in its pipelines, essentially destroying the gas the company normally would profit from, said Kevin Thompson, the plant's area manager.
MarkWest collects the offgasses from Flint Hills, Citgo and Valero, processes and sells the gas, he said. An estimate of the value of the gas burned throughout the day was not immediately available.
"When it's a sudden shutdown like it was today, a hard shutdown, it was instant and caused the safety release devices to be activated," Thompson said. "Of course, this is not a normal action. It's very abnormal to have power interruptions in a facility. When it's a scheduled shutdown we'll back that gas out slowly, to have a more controlled event."
In those cases, the gas is refrigerated and turned into a liquid for storage, Thompson said. Because the refrigerators also were nonoperational, the gas could not be saved, only burned. He did not know the last time the plant had lost power.
AEP serves the local plants with high voltage power, which each plant then converts using its own on-site substation, AEP spokesman Andy Heines said.
AEP officials and MarkWest employees were working to determine the initial cause of the outage and which company was responsible.
"The root cause of the initial power outage, we don't know. AEP experienced some outages as well. We are working with them to try to determine the cause, but we're certainly not blaming AEP for it," Thompson said.
MarkWest is among the top 20 power consumers in the state, Thompson said, so the plant is not equipped with generators capable of supplying that amount of power.
When the power went out, valves closed at MarkWest, prohibiting the refineries' offgasses from entering the building, Thompson said. In response, the backup prompted flaring at the individual plants, which is a safety response to ensure the gas does not remain inside the plant. The Texas Commission on Environmental Quality sent workers to determine if there was any threat from the flaring, and Thompson said they concluded the community never was in any danger.
MarkWest's flaring went on longer because there was more gas at that plant.
A large fireball could be seen from as far away as Robstown and Corpus Christi. Police dispatchers were inundated with calls about the thick, black smoke that blanketed much of the city's downtown for hours.
Thompson said intermittent flaring went on after the initial three-hour period but the plant expected to be operational late Saturday.
A second power outage about 12:15 p.m. affected the midtown area when an electrical cable burned out at the Morris Street substation.
The two events originally were believed to be part of the same outage.
"It could be a completely different outage, unrelated. With MarkWest they have their own electrical system within their plant," Heines said. "We just deliver high voltage to them. Sometimes it's on their side ... it's a different type of outage, really, so the large industrial customers take it from there."
As AEP workers manually replaced the cable at the substation, about 500 residential customers were without power, and Christus Spohn Hospital Memorial, which lost power for just seconds, switched to a backup generator.
Katy Kiser, a hospital spokeswoman, said the hospital lost power before noon and power was restored about 2:45 p.m. She said the hospital's patients were not adversely affected.
"The emergency generators did what they were supposed to do, according to maintenance. They're still looking into what happened," Kiser said. "It was more of a city issue, or an AEP issue, than a hospital issue."
Kiser said that staff will not perform a scheduled surgery when the hospital is operating on a backup generator.
She did not know how many surgeries were planned during that time period but said those surgeries would have been delayed until the generators no longer were the main source of power.
Copyright 2012 SCRIPPS Howard Publications. All Rights Reserved.
(Originally published August 11, 2012, in the Corpus Christi Caller-Times.)