Least we forget, Star Trek V: In Search of God, or whatever that crapfest was called. A fun list though.

Two others that should be noted were the New London, Texas school explosion that killed 295 grammer school students and faculty members in 1937, and the Dioxin contamination of Times Beach, Missouri that resulted in the evacuation of an entire town in 1983. Eventually the entire town was obliterated. The chemical clean-up took fourteen years.