Im not sure if everyone else's interview tone was the same, but mine seemed somewhat tense. They did not do any small talk or anything. They were all nice, just no chit chat. There were two BNSF guys there and 1 BNSF HR lady in the interview. I showed up about 20 minutes early and they were waiting for me, and the interview started immediately. They asked to give a little background on yourself, and then ask a ton of legal questions like "have you ever had a speeding ticket in the last seven years", "do you have felonies or misdemeanors"... Stuff like that. Then came the interview questions. The questions are all asked off of an interview guide. all of the questions are in the format of "tell me about a time this happened...". I would recommend being specific with your answers like using names and dates.
hope that helps. Let me know if you have more questions. The people on here have been very helpful with me.