Typically you have to be a member posted to the base, and have an airsoft club authorized by the base commander to be allowed to actually play in the facilities.
Like Brian said there is a thread on here if you run some searches for it, that covers this entire topic and the one success story that happened, but also ended up getting shut down so it became a non success story.
Saskatchewan Age Verifier! Contact for more Info.
http://airsoftcanada.com/showthread.php?t=174161 - Honour & Respect your fellow players! #Airsofthonourandrespect