Disposing of used grease safely

The bucket is full and you're standing there holding it. Don't tip it down the sink. Here's what the official sources say instead.

Most of what follows comes from advice written for kitchen grease, which is what pellet grill drippings are. The sources don't mention grills. Your local council's rules come first, because they differ between places.

Step one: let it cool

Camp Chef's cleaning guide says to let grease fully cool before you handle it.¹ It also says to make sure the grill is completely cool and unplugged before any cleaning.¹

Step two: put it in a container and bin it

Clemson Cooperative Extension in the US gives a short routine. Can or bottle the grease, let it cool, then seal it. After that, take it to a local recycling centre or put it in household rubbish.²

New York City's environmental department gives some container ideas. Grease can go in a frozen juice container, a beverage carton or a take-out container. It also says you can put cooled grease in a plastic bag and freeze it before discarding.³

Camp Chef describes a grill-specific version of the freezing idea. You put the grease bucket in the freezer, pry out the frozen puck and toss it.¹

These are US sources. Rules in Australia, the UK, Canada and elsewhere are set by local councils or water and waste authorities, so check yours. Some places run a collection or recycling point for cooking fats, and some don't.

Why not the drain?

Clemson's page is blunt: never pour cooking oils or grease down the drain.² The reason it gives is that the grease cools and solidifies in your septic or sewer lines, causing backups.

New York's page says the same thing in other words. Grease can build up so much that it clogs pipes completely.³

Hot water and soap don't fix it. Clemson says they don't eliminate the grease, because it can reform and solidify in pipes.²

Soaked liners and the leftover film

Here the sources run out. The pages I've read cover liquid and solid grease, not a foil liner soaked in it. They don't say whether it counts as household rubbish where you live.

I can't point to an official page that covers it, so treat it as a question for your local council or waste service. Your grill's manual may also say something about its own liners.

Camp Chef's other cleaning method for the bucket is to wipe it with a paper towel once the grease has fully cooled.¹

Keep it out of the street drain too

New York's page also says nothing of any kind should be poured down a catch basin, storm sewer or street drain.³ That covers the gutter outside your house.

For what a bucket and liner do before you reach this point, see what the bucket and liner are for. For why it matters not to let it pile up, see build-up over time.