Cooking oil or grease sticks to pipes when poured down the drain and may cause possible backups and/or sewage spillage. Flushing pipes with hot water will not always clear clogs. Use the following steps to safely dispose of any cooking oils.
Put a paper towel in a can and pour (cooled) cooking oil into the can and throw it in the trash. When grease is solid, scrape it into a can and throw it in the trash.
Check with a local restaurant or pizzeria to see if they allow the use of their drums or bulk tanks to pour a large amount of cooking oil into.