Deer Park, Texas — At least two workers at a Houston-area oil refinery were killed Thursday in a hydrogen sulfide leak at the plant, triggering urgent warnings to nearby residents to stay indoors until until authorities later determined that the public was not in danger.
Nearly three dozen other people were transported to hospitals or treated at the scene, Harris County Sheriff Ed Gonzalez said. Hours after the leak began, Gonzalez said the area was still dangerous for investigators and authorities might not be able to enter until Friday.
The plant is operated by Pemex, Mexico’s state-owned oil company, and located in suburban Deer Park.
Gonzalez said the gas release occurred during work on a flange at the facility, which is part of a group of refineries and oil plants that makes Houston the nation’s petrochemical heartland.
Pemex said in a statement that investigations were ongoing and operations had been “proactively halted” at two units in an effort to mitigate the impact.
Local officials issued a stay-at-home order, but lifted it a few hours later after air monitoring showed no risk to the surrounding community, Deer Park Mayor Jerry Mouton said.
CBS Houston affiliate KHOU-TV chief meteorologist David Paul said the wind was calm Thursday evening.
Hydrogen sulfide is a foul-smelling gas that can be toxic at high levels.
“Other than the odor, we have had no verifiable air monitoring to confirm that anything came out of the facility,” Mouton said.
Television crews showed several ambulances and emergency vehicles at the scene. Gonzalez initially posted on the social platform
The leak prompted Deer Park’s second shelter-in-place order in the span of a few weeks. Last month, a pipeline fire that burned for four days forced surrounding neighborhoods to evacuate.