Is it permissible for a cohain to visit the mikvah of the Arizal in Tzefat, which is on the descent to the beit kevarot?

I don't know of any Halachic permit for Cohanim to enter a cemetery for a Mikveh. though, I have just seen a response from Rav Shmuel Eliyahu, the rabbi of Tzefat, dated Av 5763, he wrote that you can walk through the upper dirt path near the water reservoir, that path in supposedly clear from graves.