Numbers 19:7-10

7Then the priest must wash his clothes and bathe himself in water, and afterward he may come into the camp, but the priest will be ceremonially unclean until evening.

8The one who burns it must wash his clothes in water and bathe himself in water. He will be ceremonially unclean until evening.

9“‘Then a man who is ceremonially clean must gather up the ashes of the red heifer and put them in a ceremonially clean place outside the camp. They must be kept for the community of the Israelites for use in the water of purification – it is a purification for sin.

10The one who gathers the ashes of the heifer must wash his clothes and be ceremonially unclean until evening. This will be a permanent ordinance both for the Israelites and the resident foreigner who lives among them.