Bava Batra 102: A Quick Burial
More on the spacing of found buried bodies - and when the presumption is that you have found an ancient burial ground, based on the spacing (depending on the dispute with regard to burial details). Also, a dispute between the sages and R. Shimon in the mishnah vs. that of both sides in the baraita. Plus, the contrast to a burial ground and a vineyard, in terms of proximity.