A hydrogen sulfide gas leak killed two people and injured another 35 at the PEMEX facility in Deer Park Thursday.
The leak led to both sides of Highway 225 being shut down and the entire city of Deer Park being put under a shelter-in-place order.
The City of Deer Park says that their CodeRED alert system malfunctioned during the incident, resulting in some residents receiving duplicated or incorrect messages. Meanwhile, other residents didn't receive any alerts at all.
PEMEX, or Petroleos Mexicanos, is the Mexican state oil company and took control of the facility just two years ago after buying the majority stake of the refinery from Shell.
The U.S. Chemical Safety Board is investigating the leak.
Around 10:00 p.m. last night, the city of Deer Park announced that the shelter-in-place order had been lifted. There may still be a lingering smell of rotten eggs in the area, but according to Deer Park Mayor Jerry Mouton Jr., there is no danger.