Emergency crews were dispatched around 8:30 a.m. to the 1300 block of Melvin Road near City Line Avenue in Schuylkill Township, according to the Phoenixville Fire Department.
The Chester County Hazardous Materials Response Team was at the scene, fire officials said.
No injuries were reported.
A shelter-in-place was temporarily issued for nearby Phoenixville Middle School and Phoenixville High School, 6abc reports.
The scene was cleared a little after 12 p.m.
The cause of the incident was undetermined, Valley Forge Volunteer Fire Company Chief Rafael Henin told Daily Voice.
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