That's an excellent and very important safety question. The direct and crucial answer is: No, you should never dispose of hot ashes or coals from a public barbecue into a standard urban trash bin.
While these bins are sturdy, they are not designed to be fire-resistant. The materials inside—plastic liners, paper waste, food scraps, and other flammable debris—can easily ignite from the residual heat. A seemingly "cool" ash pile can retain intense heat at its core for many hours, even a full day after the barbecue is out.
Disposing of them in a public bin creates a serious fire hazard, risking a bin fire that can spread to surrounding areas. So, what should you do?
1. Use Designated Ash Receptacles: Some parks provide special, metal ash disposal units near barbecue areas. Always look for these first.
2. The Water Drench Method: If no special unit exists, thoroughly douse the ashes and coals with water. Stir them carefully and douse them again until they are completely cold to the touch. *Then* you can dispose of them.
3. Wait It Out: If water isn't available, let the coals cool in the barbecue grill for several hours, ensuring they are fully extinguished and cold before considering disposal.
4. Pack Them Out: As a last resort, once completely cold, you can seal them in a metal container and take them home for disposal.
Protecting our public spaces is a shared responsibility. Taking those extra few minutes to cool coals properly prevents dangerous fires and keeps maintenance workers safe. Always err on the side of caution—when in doubt, let them cool longer.