Thousands of gallons of oil have spilled into a bayou.
The Coast Guard, Environmental Protection Agency and the Texas General Land Office are working to clean up the mess in Highland Bayou, which is near Hitchcock.
Officials said an oil and waste water tank owned by Dune Energy released about 84,000 gallons of an oil and waste water mixture on Thursday morning.
The tank was surrounded by a spill containment berm that was able to hold a majority of the spill.
About 4,200 gallons of oil got into the bayou, officials said.
Containment booms have been put out in three areas to minimize the environmental impact.
The cause of the incident is under investigation.