Leviticus 4:7-8

7And the priest shall put some of the blood on the horns of the altar of fragrant incense before the Lord that is in the tent of meeting, and all the rest of the blood of the bull he shall pour out at the base of the altar of burnt offering that is at the entrance of the tent of meeting.

8And all the fat of the bull of the sin offering he shall remove from it, the fat that covers the entrails and all the fat that is on the entrails