The NTSB concluded that the torch had likely ignited flammable methane gas in the hold, triggering the explosion. This procedure, known as “innage reduction” was not done often and the report indicates it was last performed on the Hunts Point five years earlier. In the aftermath of the accident, the DEP issued two memos directing personnel to review procedures for hot work and hazards associated with sludge. Damage to the Hunts Point tanker is estimated at $10 million according to the NTSB report. For more details on the accident, see the full NTSB report.