The certainty of the Richmond Fair became a little less certain yesterday when word spread that the city police aren’t going to issue a permit for the 10-day carnival-style festival. “I spoke to Philip [Downing, the fair operator] yesterday and advised him that a permit for the carnival is not going to be issued by the PD and that he will be receiving a letter the first part of the week,“ Assistant Police Chief David M. McCoy said in an e-mail.