Leviticus 4:7-8

7The priest shall also put some of the blood on the horns of 1the altar of fragrant incense which is before the Lord 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, which is at the doorway of the tent of meeting.

8And 2he shall remove from it all the fat of the bull of the sin offering: the fat that covers the entrails, and all the fat which is on the entrails,