Tosco Avon Fire
February 23, 1999
California Department of Industrial Relations
Division of Occupational Safety and Health
· Visible Leak observed at approximately 1:00 p.m. from the fractionator tower block valve on the naphtha draw line, 50-unit fractionator
· Steps taken to isolate and stop leak on naphtha draw line.
· Naphtha draw line stops leaking.
· Work requests for repair/replacement of naphtha draw line.
· Inspection determines thinning in top section of naphtha draw line.
· Additional inspection of naphtha draw line.
· On 2/13/99, leak reappears at site of leak noticed on 2/10/99; naphtha stripper refills with naphtha, valves are retightened and naphtha stripper is pumped out.
· Original leak site on naphtha draw line resumes weeping.
· Valves re-tightened, naphtha stripper pumped out again.
· Bleeder valves in line noted as plugged.
· Attempt to clear bleeder valves fails.
· Line work continues.
· Line again inspected.
· Preparation for line removal next day.
Timeline: Tosco Avon Fire (Continued)
· Work on naphtha draw line (NDL) in preparation for its removal.
· Attempts to drain reveal control valve sludged up after being blocked in.
· Top section of NDL is cut and removed to grade.
· Further attempts to drain NDL again fail. Solid plugging found.
· Liquid leaks from NDL as second cut is made.
· Draining operation continues and second cut on NDL resumes.
· Naphtha leaks out second cut, then top cut of NDL, dousing workers.
· Fire breaks out at 12:10 p.m.
· Initiation of emergency shutdown of 50-Unit Fractionator and firefighting/rescue efforts.
· Fire under control at 12:38 p.m.