Two more Houston-area school districts near a burning petrochemical tank farm have called off classes.
The Galena Park and Sheldon school districts joined the Deer Park and La Porte public school systems in cancelling Friday classes.
The systems' officials were taking a cautious approach for fear of a repeat of Thursday's shelter-in-place warning because of conditions at the Intercontinental Terminals Co. tank farm, where a fire this week raised fears of toxic contamination.
Classes have been canceled for Friday in two public school systems near a Houston-area petrochemical storage site where a fire this week raised fears of toxic contamination.
In statements issued Thursday afternoon, the Deer Park and La Porte school districts announced the cancellations because of what the La Porte district statement called "an abundance of caution."
The Deer Park district statement noted that conditions at the Intercontinental Terminals Co. that led to a shelter-in-place warning Thursday could recur Friday. It said the district wanted to "avoid a situation where another shelter-in-place might be called as children are arriving at or leaving school."
Meanwhile, teams and contractors from local, state and federal officials are working under a unified command to evaluate what effect the fire and efforts to extinguish it have had on Tucker Bayou and the Houston Ship Channel, waterways that surround the ITC site.
Officials with a Houston-area petrochemical storage facility say crews are working to empty a storage tank that they believe emitted dangerous benzene vapors that led authorities to ask residents to remain indoors for several hours.
Intercontinental Terminals Co. spokeswoman Alice Richardson said Thursday company officials believe winds shifted foam that was sprayed over the tank, which has a gasoline component, allowing benzene vapors to escape.
The foam has been reapplied and crews are transferring its contents to another tank.
Authorities issued a shelter-in-place order early Thursday before lifting it hours later.
A fire at the facility began Sunday and was extinguished Wednesday before briefly flaring up.
The Environmental Defense Fund and researchers from Texas A&M University say they will collect water samples from Galveston Bay to measure what pollutants might be flowing from the shipping channel near where a fire raged at a petrochemical storage facility.
The samples will be collected Friday and will be tested for such chemicals as benzene and toluene.
Elena Craft, a senior health scientist at the Environmental Defense Fund, says the researchers will get real-time results for most pollutants.
She says samples will also be collected to test for perfluoroalkyl and polyfluoroalkyl compounds, or PFAS, which are found in foam firefighters were using Thursday to try to prevent flare-ups at the Intercontinental Terminals Co. facility in Deer Park.
Those test results would not be available for a few weeks.
Officials have lifted an order to remain indoors after several readings showed that the air quality had improved near a scorched petrochemical storage facility in suburban Houston.
City officials in Deer Park lifted the order Thursday and reopened roads around the Intercontinental Terminals Co., where a fire burned for the previous three days.
They say several state and other agencies will continue to monitor the air after elevated levels of benzene were detected early Thursday, prompting the shelter-in-place order.
The fire began Sunday and sent a huge, dark plume of smoke thousands of feet into the air before being extinguished Wednesday.
The tanks that caught fire contained components of gasoline and materials used in nail polish remover, glues and paint thinner. ITC says 11 of the 15 storage tanks located in the area where the fire occurred were damaged.
Authorities haven't revealed the cause of the blaze.
A woman who lives near a Houston-area petrochemical storage facility that burned for days says she decided to leave home with her two children after authorities told people to stay indoors due to elevated levels of benzene in the air.
Kristin Crump said Thursday that she placed damp wash cloths over her mouth and those of her 13- and 6-year-old children as they walked to their car and left to stay with family elsewhere.
It is the second time Crump has left her home since the fire began Sunday at the Intercontinental Terminals Co., which is less than 2 miles (3.2 kilometers) away.
She left the area Tuesday with her children after they complained of headaches. The three returned a day later.
The fire was extinguished Wednesday but officials said early Thursday that elevated levels of benzene had been detected.
Authorities say it appears that the suppressive foam firefighters are using at a Houston-area petrochemicals storage facility is separating at times and allowing dangerous benzene vapors to escape before another layer of foam can be applied.
Harris County Fire Marshal Laurie Christensen said at a news conference Thursday that crews are applying layer after layer of foam where several storage tanks burned at the Intercontinental Terminals Co. in Deer Park, southeast of Houston.
The fire began Sunday and was extinguished Wednesday, but a flare-up occurred later Wednesday that crews are working to prevent from occurring again.
Authorities say winds are light Thursday so the vapors aren't spreading beyond the immediate area of the ITC plant.
They say orders to stay indoors are being done "out of an abundance of caution."
At least three area school districts cancelled classes Thursday.
National Guard troops are on the scene and residents are being told to stay inside after elevated levels of benzene were detected near a Houston-area petrochemicals storage facility that caught fire this week.
Harris County officials said Thursday that the Guard and hazardous materials teams have established perimeters around the Intercontinental Terminals Co. in Deer Park.
The Environmental Protection Agency said Wednesday that benzene levels near the facility didn't pose a health concern. But authorities now say a shelter-in-place order following "reports of action levels of benzene or other volatile organic compounds" within Deer Park.
Several school districts also canceled classes for the day, citing "unfavorable air quality conditions."
The fire started Sunday, sending a huge, dark plume into the air, and spread to storage tanks holding components of gasoline and materials used in nail polish remover, glues and paint thinner.
This story has been corrected by deleting an erroneous reference to the Texas Environmental Protection Agency. The EPA is a federal agency.
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