Plot hole: During the flashback scene showing how Chloe and her father survive the house explosion it is explained that there was a team in the house and they grab Chloe and her father and rush them into a tunnel just seconds before the house explodes. However, as seen in the episode Covenant, Chloe is standing next to the door and Chloe's father is more than 15 feet away from her when the door of the house shuts. As soon as that door shuts the house explodes so unless this S.W.A.T. has Clark's super speed ability this would be very much impossible.
Plot hole: Mayor Tate and Lex have a discussion about bribes and Tate says this is his 4th term. In last season's episode "Crush", Pete gets a job as a summer intern on Mayor Spiegel's re-election campaign. So how is it possible for Tate to have been on his 4th term when in the previous year Spiegel was Mayor?