Deuteronomy 23:10-13

10If there is any man among you who becomes unclean by some occurrence in the night, then he shall go outside the camp; he shall not come inside the camp.

11But it shall be, when evening comes, that he shall wash with water; and when the sun sets, he may come into the camp.

12“Also you shall have a place outside the camp, where you may go out;

13and you shall have an implement among your equipment, and when you sit down outside, you shall dig with it and turn and cover your refuse.