Thanks to a complete lack of material in this niche, the site (http://pengapplicant.ca) gets a decent amount of organic search traffic given the niche size (2k page views per month) and I make about $15/month in Adsense. Recently I was also contacted by someone who sells materials for the application and exam and have become an affiliate for them. It's only been one month, but i've already made one referral which netted me $100. So passive income on this after hosting costs is probably $220-ish and will be more in 2017 hopefully with more affiliate sales. Obviously very small potatoes, but I never set out to make any money for this and it looks like now it will at least cover my yearly professional dues ;)
To be honest, the best part is the messages I get from people saying how I helped them get their license. That's a much nicer feeling than the $.