The order, which was an update from a shelter-in-place issued earlier Wednesday, was put in place due to elevated levels of 1,3-Butadeine, a chemical made from the processing of petroleum.
The Jefferson County Office of Emergency Management said Thursday afternoon that TPC staff had been working to stop leaks that contributed to those levels.
"As a result of the actions taken, the levels have now been greatly reduced to non-irritating amounts. Air monitoring will continue to ensure the levels are being maintained at their current measurements. Due to the improved current conditions, the City of Port Neches and Jefferson County Judge Branick are lifting the shelter-in-place and voluntary evacuation order for the City of Port Neches," the office of emergency management posted.
Last week's blast at the plant 95 miles east of Houston injured two employees and a contractor.
A second blast was captured on camera while flames were still raging from the original explosion.
The video above is from a previous report.
Impact and thunderous sound of Texas explosion caught on camera
Residents try to readjust after seeing their homes damaged
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