Waste household latex paint should be dried out so that it can be disposed of by your trash disposal company. The paint must be dried out because landfills are not allowed to accept liquid wastes. Procedures include:
For quantities less than 1/4 of a can of paint, remove the lid and allow the liquid to dry outdoors in a well-ventilated area away from potential ignition sources, children and pets. Periodic stirring may be necessary. Once dry, leave the lid off of the can so your trash hauler knows the paint is dry and dispose in the trash.
For quantities greater than 1/4 of a can, mix the paint with kitty litter or other clay-based absorbent in a plastic tray, bucket or a box lined with a plastic trash bag until the absorbent is moist, but not dripping.
Set the mixture outdoors in a well-ventilated area away from potential ignition sources, children and pets. Allow to dry. If you have additional paint, this procedure can be repeated in layers.
Wrap the dried absorbent in the trash bag and put it in your trash.
Some paint retailers sell a product specifically designed to dry paint in the can - check with your local paint or hardware store for information on these products. Once dry, leave the lid off of the can so your trash hauler knows the paint is dry and dispose in the trash.
Empty paint cans can also be placed in the trash. Leave the lids off of the cans so that your trash hauler can tell they are empty and/or dried out.
These procedures are intended for small quantities of paint from a household only.