The Federal Railroad Administration says trains started using the Paulsboro bridge again Monday, one day after the last derailed tanker car was cleared from the site and testing was complete.
Repairs were being done even as the clean-up continued on the swivel-style structure on a line that serves several plants along the Delaware River.
A half-dozen cars derailed on Nov. 30. One tanker released vinyl chloride into the air.
While no one was seriously sickened, more than 300 homes and businesses were evacuated for parts of the next week.
The National Transportation Safety Board is investigating, but a full report is not expected for at least several months.