Who do I contact to find out how to get rid of old half filled paint cans and unmarked cans containing various liquids in my garage?
Without knowing your whereabouts, it's difficult to give you much in the way of specific suggestions.
You might try the following:
Do a Google search to see if your city or county has a hazardous household waste drop-off center. My area has one that's open at specific times during the week, most items are accepted at no charge.
If you have paint (or other stuff) that's still usable, do another Google search to see if you have any local 're-use' centers. These places usually accept donations of usable goods (as long as they are not hazardous). The items are then either given to people in need or sold to people who prefer to 'go green' and buy recycled products.
Discarding oil-based and other dangerous paints: Oil-based paint is flammable and the fumes can be dangerous. Lead paint, mold-retardant paints, old paint and aerosol paints are also dangerous to health and the environment. To discard, take them to a hazardous waste disposal center. Many landfills also reserve certain days of the year when they collect old paint and other potentially toxic substances. Check with your local waste management office for a list of dates.
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