Application: I applied online. I received e-mail from the O2 manager to schedule a phone interview with her and the plant manager. Phone interview questions were based on Behavioral Questions and questions from my resume. A few weeks later, I was invited to an on site interview at 3M in July, 2016. Interview: There was an another candidate for the interview. There were three groups for the interview (Engineers, Managers with HR and current 02 Engineers). Each candidate interviewed with those groups and we took a tour of the plant. Overall the process was pretty informal. I had an offer the day after I interviewed.