What caused a leak at Dow Chemical in La Porte?

A leak at Dow Chemical Wednesday morning is still causing concern. 

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The road leading to the Dow Chemical Bayport Plant in La Porte is still closed as emergency officials try to figure out what caused Hydroxy Ethyl Acrylate, an acrylic used in coatings and adhesives to leak from a truck there at the plant.

"We don’t know yet how the materials inside that tanker became unstable," explained Harris County Judge Lina Hidalgo. "It is a silver tanker truck like the ones you see going down the highway."

Hours after the chemical Hydroxy Ethyl Acrylate began leaking from a valve in the truck at the Dow Chemical Bayport Plant area leaders were working to find out everything about the leak even after it apparently ended. 

"What is not clear is whether it stopped because the reaction has stopped or whether it stopped because there’s so much reaction, so much heat and pressure being built up within that tanker that it’s clogging that vent," said Hidalgo.

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"Our Harris County Fire Marshals Office, Pollution Control, public health, we are all part of that Unified Command and so is Dow. We have approximately 75 people on site," says Harris County Fire Marshal Laurie Christensen. 

The shelter in place that had been ordered in La Porte was lifted by lunchtime as emergency officials learned in addition to the HEA in the tanker, there is also MMA Methyl Methacrylate. 

"Dow informed us that those are chemicals that are used in plasticizers and so we’re just waiting for this to calm down and cool off so it doesn’t polymerize and create an explosion," adds Dr. Latrice Babin with Harris County Pollution Control Services. 

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An evacuation of everyone within a half-mile radius of the leak was ordered. Although, two residents chose to stay and two other chemical plants continued their operations with a small staff in place. 

"The plants are blast-proof but of course, it’s a concern," says Judge Hidalgo. 

Breathing the chemicals, according to pollution control, can cause nose and throat irritation but we’re told the air quality is continuously being monitored and no dangerous levels have been detected.

By the way, after the big ITC fire, Harris County received $1-million in damages. 

On Wednesday, Harris County Attorney Christian Menefee said "We’re considering all legal options to keep Harris County residents safe."

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