Gradient Environmental Chemist interview questions

I inquired about an environmental chemist position through their continuous recruiting posting on their website. Received an email a week or two later about scheduling a phone interview with two Principals. A week or so following the phone interview, I was asked to come in for an informational interview. Prior to the date of the interview I was given an assignment of summarizing a scientific paper written by a Principal. The interview comprised of ~9 rapid, 30-minute interviews with Principals and Senior Associates, as well as lunch. The process was largely painless and did not have too many difficult questions. I am guessing that if I was more competitive I would have had a follow-up, more rigorous interview.