Most recipes will now produce additional useless Scrap which you must filter out and sequester. Scrap has no use and cannot be burned for fuel. Because every single recipe is affected, the scale of the waste is enormous and its polluting effects will quickly become a problem.

• Scrap: clutter which can't be used as an ingredient, burned or even stacked.
• Garbagefill: Polluting tiles which can be paved over to negate their polluting effects.
• SacrificeZone: Polluting tiles which can't be paved over! You can reclaim it by killing a biter atop the infected tile.
• Voiding Machines: These can sequester an infinite amount of scrap, but they are permanent.
• And don't even try to get rid of Scrap by putting it in a chest and then blowing it up with grenades!

Protip: When starting from scratch, you might want to rush the logistics research that adds filter inserters.