Materials that are potentially explosive must be disposed of in very specific ways and should never be placed in directly into your regular trash before remediation.
Contact your local police department to dispose of firearms as well as gunpowder and ammunition.
Contact your local fire department to dispose of flares.
To dispose of used fireworks, residents should soak used fireworks for several days, then place them into a sealable plastic bag prior to putting them in the trash. By placing them in the sealable bag, it reduces the chances of them drying out. Use a similar technique for the disposal of unused fireworks. Residents should cut off the top of unused fireworks before submerging them in water until they are mushy. Place the mushy pieces into a sealed plastic bag before disposal in your regular trash.