Mississauga Train Wreck Presented to ES317 at UWO

Mississauga Train Wreck • Presented to ES-317 at UWO in 1999. • By Dick Hawrelak

The Incident • • • Midnight, 10 Nov 79. 24 of 106 railcars derailed at Mavis Road. 11 propane cars. 3 toluene cars. 4 caustic cars. 1 - 90 ton chlorine car.

The Incident Cont’d • Fire broke out almost immediately. • Within 30 minutes, 3 of 4 propane cars BLEVEd. • Sheets of steel were hurled 2, 000 ft. • Some property damage, no casualties. • There was no apparent Cl 2 release at this time.

What To Do? • First responders decided to perform Cl 2 dispersion studies in case Cl 2 had not been released at this time. • Called Dow Chemical for help. • Worst Case Scenario - 180, 000 lbs instantaneous loss.

Results Of Dispersion

Decision Time ? ? ? • Decided to evacuate 217, 000 people. • Used TV, radio, street patrol, knocked on doors. • Evacuation took 24 hours for total population. • Majority returned after third day. • All returned after sixth day.

Evacuation Data

The Failure • It was determined that the derailment was caused by a journal bearing failure, or “Hot Box” on a toluene car. • First responders had to withdraw to 1, 500 ft. • A brave photographer determined the Cl 2 car was within 40 ft. of propane car. • The Cl 2 car had a major hole 2. 5’ x 3’.

What happened to Cl 2? • 160, 000 lbs of Cl 2 was lost. • Propane fires created extreme heat island. • Cl 2 drifted upward with heat intense heat rise or was consumed in the reaction. • No one in Mississauga, at any time, ever smelled Cl 2. • For once, the Gods were with us this time!!