(MCT) — PAULSBORO, N.J. — Residents near the site of a freight train derailment Friday that knocked out a recently rebuilt bridge in Paulsboro and spewed thousand of gallons of a hazardous chemical into the air are not quite out of danger.

While the immediate threat passed within three hours of the 7 a.m. EST accident, removing the remaining vinyl chloride from a tanker car that ruptured, and pulling three others carrying the toxic chemical from the Mantua Creek, will require what several officials called a delicate operation.