The best way to dispose of antifreeze to reduce the amount of damage it does to the environment, is to take your car to an auto service center that has an antifreeze recycling machine.

If there are no antifreeze recycling machines in your area, then flushing it down the drain is the next best step, though it is illegal in some areas and can still cause pollution. You should call your local waste water treatment facility to determine if they can accept antifreeze. If they can, then you can flush diluted anti freeze down your drain one gallon at a time. The best time to flush the diluted antifreeze is usually during the week, when the sewage system is in full use so that the antifreeze can be passed through the system quickly.

Additionally, some landfills accepts non hazardous antifreeze.

Additional Information

Antifreeze should not be poured down storm drains, into rivers or on the ground.

Store Antifreeze in a closed container away from animals, as they are sometimes attracted to its scent.

Do not mix antifreeze with any other waste product that is thrown in the trash.

Use new or clean containers to store antifreeze, so that it is not mixed with hazardous substances like gas.