The point géodésique was/is located west of the Dorval VIA Rail station. At the level of the railroad, standing on the overpass above the Côte de Liesse Expressway (autoroute 520), looking at the fence to the south, one can see the faded orange witness sign for 70K4546. According to the witness sign, the marker is 5.25 metres away. It is likely that the marker was/is near the metal plate in the grass immediately south of the shelter for those awaiting the trains.
I am no longer able to gain access to the details for specific markers in the géodeq database.
http://webapp.geod.nrcan.gc.ca/geod/data-donnees/station/report-rapport.php?id=70K4546