HOUSTON (Reuters) - Two Houston-area cities told residents to stay indoors and closed schools on Thursday due to air pollution from a petrochemical plant fire, then lifted the travel restrictions after airborne levels of the chemicals abated.
The three-day blaze at Mitsui unit Intercontinental Terminals Co (ITC) in Deer Park, Texas, was extinguished on Wednesday after sending a plume of smoke over the area from 11 burning fuel tanks. No injuries were reported, but air monitors detected high levels of benzene, a toxic chemical linked to cancer.
The cities of Deer Park and Galena Park, both east of Houston, had issued shelter-in-place advisories to residents after reports of high levels of benzene or other volatile organic compounds (VOCs) were detected. Both orders were lifted by 2 p.m., officials said.
Residents had been advised to remain indoors, turn off air conditioning and heating systems, and close doors and windows, making sure to plug any gaps, holes or cracks with wet towels or sheets.
A state highway was closed in Deer Park. School districts in the two cities and four other nearby school systems cancelled classes.
“I’m not worried,” said Lillie Patton, a resident of Pasadena, Texas, one of the communities that closed schools because of danger from benzene fumes. “They’ve taken the necessary precautions. I appreciate they are using their brains and common sense.”
The benzene fumes likely originated from giant tanks of gasoline that had been breached by the fire and exposed to the air. Workers on Thursday were removing fuels from the damaged tanks, which each can hold up to 80,000 barrels.
An ITC spokeswoman declined to say when the work would be completed. Adam Adams, a U.S. Environmental Protection agency (EPA) official monitoring the site, estimated the effort could be finished on Thursday.
The fire, which began on Sunday morning, destroyed 11 of the 242 giant tanks at ITC’s terminal, capable of holding up to 13.1 million barrels of fuel. No one was injured during the fire, and a cause has yet to be determined.
Benzene has a pungent odour, and inhaling it can irritate the skin, eyes and the respiratory system, while severe exposure can harm the nervous system or lead to unconsciousness, according to experts. The EPA classifies benzene as a carcinogen.
The state’s environmental regulator said monitors detected up to 190.68 parts per billion of benzene in Deer Park early Thursday, a level that can cause headaches and nausea. Deer Park sits on the Houston Ship Channel, an area with nine oil refineries and dozens of energy related facilities.
Total Petrochemicals and Refining USA, a unit of France’s Total SA, emptied several of its petrochemical tanks as a precaution, it reported to the Texas Commission on Environmental Quality (TCEQ). The flaring released thousands of pounds of propene, a volatile organic compound, it said.
Royal Dutch Shell on Wednesday had ordered employees to avoid an area at its facility where it had detected elevated levels of benzene.
“Given our very conservative air quality standards we are at a level where out of an abundance of caution there should be a shelter in place,” Lina Hidalgo, the chief executive of Harris County which encompasses Houston and its suburbs, said during a morning news conference.
“This is a dynamic situation,” Hidalgo said.
Harris County Fire Marshal Laurie Christensen said firefighters have continued to apply a foam blanket on the burn area to stop the escape of dangerous fumes.
TCEQ, one of the groups investigating the incident, estimated that on the first day of the fire, 6.2 million pounds of carbon monoxide and thousands of pounds of nitrogen oxides, sulphur dioxide and toluene were released. The regulator has cited ITC for violations of state air-emissions rules 39 times over the past 16 years.
The EPA is to test local waterways for possible contamination from the millions of gallons of water and foam dropped on the fire since Sunday.
Reporting by Gary McWilliams, Erwin Seba and Jennifer Hiller in Houston; additional reporting by Brendan O'Brien in Milwaukee; Editing by Bernadette Baum and David Gregorio