Leviticus 11:35-39

Moreover, everything on which part of their carcass may fall becomes unclean; an oven or a stove shall be smashed; they are unclean and shall continue as unclean to you.

Nevertheless, a spring or a cistern collecting water shall be clean, though the one who touches their carcass shall be unclean.

Now if a part of their carcass falls on any seed for sowing which is to be sown, it is clean.

But if water is put on the seed and a part of their carcass falls on it, it is unclean to you.

‘Also if one of the animals dies which you have for food, the one who touches its carcass becomes unclean until evening.