A faulty pressure relief valve is being blamed for the release of 325 pounds of sulfur dioxide at the Delaware City Refinery owned by PBF Energy.
The incident occurred Saturday at 10 a.m., with information released by the Delaware Department of Natural Resources Environmental Release Notification System.
The release remains under investigation.
Sulfur dioxide is associated with the refining process. Releases occur when pressures build due to equipment failures or other causes.
This chemical or substance is considered to be hazardous by the EPA. This incident is under investigation by DNREC.