BP came to my campus the day before the interview and had a massive Q&A with all majors from industrial engineering to chemical engineering and everything in between. I met with my interviewer and introduced myself.
The actual interview was very easy and straightforward, typical of an intern-level behavior analysis interview. Then there was a simple technical question. He handed me a piece of paper with a process on it and asked multiple different questions. There was NO math, and it was all conceptual.
Overall, the HR people and the interviewer were friendly and seemed like they wanted me to do well.