A fatal explosion at a waste treatment plant in Germany was likely caused by a chemical reaction, according to an interim report.
Seven people were killed in the explosion in the Chempark industrial zone of Leverkusen on July 27, and 31 others were injured. All of the victims worked at the chemical site.
Storage tanks containing chlorinated solvents caught fire in the Currenta company’s waste treatment center, sending a huge plume of black smoke into the air.
A “significant” quantity of particles was then released in the surroundings after the explosion.
A first investigation into the incident was presented by local officials to the Cologne district government on Monday.
The report found that a chemical reaction “probably” caused the waste liquid in a waste storage tank to self-heat rapidly, resulting in an increase in pressure that the tank could not withstand.
“The whole process went so quickly that the security mechanisms were no longer able to take the pressure off,” the report adds. “When the pressure exceeded the design pressure of the tank, it exploded.”
Currenta said in a statement that the initial findings were consistent with his own investigations.
The Cologne district government said it was waiting for further expert analysis before it could draw firm conclusions about the cause of the explosion.
The Cologne prosecutor’s office and police have also opened an investigation for “suspected negligence leading to the explosion and manslaughter”.