Sources are not in total agreement when it comes to this topic. According to Job-Applications.com, Circle K generally conducts drug testing and background checks as part of the interview process.
However, anecdotal reports from those who claimed to have worked for the company say that they do this kind of testing.
You may get some bits of info by contacting a local Circle K store or via their Facebook and Twitter accounts.
To apply for open positions, go to their Working With Us page.
Check out Monster.com's Interview Tips for a Retail Management Job.