Leviticus 11:36-39

³⁶Only if the water be of fountains of water, or a pool, or confluence of water, it shall be clean; but he that touches their carcasses shall be unclean.

³⁷And if one of their carcasses should fall upon any sowing seed which shall be sown, it shall be clean.

³⁸But if water be poured on any seed, and one of their dead bodies fall upon it, it is unclean to you.

³⁹And if one of the cattle die, which it is lawful for you to eat, he that touches their carcasses shall be unclean till evening.