Leviticus 16
27 Ref And the bullock of the sin-offering, and the goat of the sin-offering, whose blood was brought in to make atonement in the holy place, shall be carried forth without the camp; and they shall burn in the fire their skins, and their flesh, and their dung.
28 And he that burneth them shall wash his clothes, and bathe his flesh in water, and afterward he shall come into the camp.