By Jeff Karoub
The Associated Press

MELVINDALE, Mich. — A hydrochloric acid leak at a metal finishing plant Tuesday forced the evacuation of 3,000 residents and schoolchildren, authorities said. At least one injury was reported.

The acid leaked from a tank on the roof of Reilly Plating Co. and created a cloud over the area, authorities said. The leak was contained in an open 500-gallon container beneath it, Fire Chief Scott Wellman said.

Lori Stallings, a spokeswoman for Oakwood Hospital and Medical Center, said the hospital was treating a resident for respiratory symptoms, and the patient was in stable condition.

Three schools in the half-square-mile evacuation zone were cleared as a precaution. Students were taken to an ice arena and a college.

Authorities let residents return about 9:30 p.m.

Hydrochloric acid is a highly corrosive liquid that can cause burns if it comes into direct contact with skin or eyes.

With rain, the chemical potentially can turn into gas and be breathed in, burning lung tissue and causing respiratory problems.

Officials were worried that the acid leak could become more of a problem if it rained. Even though rain fell during portions of the afternoon, the leak remained stable and winds had helped dissipate the vapor, Wellman said.

Brian Schlieger, an Environmental Protection Agency representative at the scene, said the air quality within the evacuation zone was within acceptable levels.

Reilly Plating ran into minor troubles with the state this year when it didn't have required air quality permits, but was working to resolve the issue, said Robert McCann, spokesman for the state environmental quality department.

An environmental cleanup company was expected to pump the acid into a truck for removal, Wellman said. Once the chemical has been taken away, people would be returned to their homes and businesses, he said.

The plant provides metal finishing to the automotive industry and others. Phone calls to the plant went unanswered Tuesday morning.

Melvindale, a city of 11,000, is 8 miles southwest of Detroit.