disposal
This word carries a strong association with finality and removal. When used in the context of waste, it implies a permanent exit from a system, often carrying a clinical or administrative tone. It is the standard term for official regulations regarding trash or chemicals, whereas words like throw away are too casual for legal or industrial settings. In the context of availability, it suggests a relationship of ownership or control. To have something at one's disposal creates an image of a toolkit or a resource bank where items are ready for immediate use. It implies a position of authority or privilege, as the person in control decides exactly how and when the resource is deployed.
Countable when referring to a specific mechanism like a garbage disposal in a kitchen sink. Uncountable when referring to the general process of getting rid of waste.