It can be hard to judge scale because the race track is so large. Here's the aerial view of the area:
https://goo.gl/maps/rBjv8FK6zry
The small parking lot in between the train station and the treed area south of the grandstand is a little bigger than the land we're talking about as the location for the Flames' new arena at Stampede Park.
That would be the most logical location because of its proximity to the train station.
Here's the original redevelopment study from 2008:
https://cdn.esd.ny.gov/subsidiaries_...ELMONT0-12.pdf