Leviticus 16:15, 21

Then shall he kill the goat of the sin-offering, that is for the people, and bring his blood within the veil, and do with his blood as he did with the blood of the bullock, and sprinkle it upon the mercy-seat, and before the mercy-seat

and Aaron shall lay both his hands upon the head of the live goat, and confess over him all the iniquities of the children of Israel, and all their transgressions, even all their sins; and he shall put them upon the head of the goat, and shall send him away by the hand of a man that is in readiness into the wilderness