This cache is located in an area where two train tracks run side-by-side. Long cargo trains occationally go by on the tracks below the nearby bridge, while a Metro train may rush in or out of the tunnel that runs beneath the cache itself.
Rest assured, you will not go anywhere near the trian tracks while searching for this cache.
Optional: I recommend parking on the sidestreet across the bridge from this cache, rather than directly at the cache site. There is a parking waypoint available.