After Antonio Dawson and Kim Burgess stop the suspects in the van, Kim is sitting in the grass. She says to Sgt. Hank Voight that the bomb has been disarmed. As she is saying that, a train goes by above them on the El. If there was a bomb in a van below the El tracks, the CTA would not allow the trains to run until the bomb had been cleared from under the tracks.
In the very beginning Kim says to Adam that she had been Frank Toma's FTO Officer. "FTO" stands for Field Training Officer, so it's redundant/unnecessary to add "Officer" to the end of FTO. She basically said she had been his Field Training Officer Officer.