The documents says that the default read_repair_chance value is 0.1, and it is also declared so in CFMetaDeta. However, when creating a column family with "create column family foo" via cli and checking with "show keyspaces" shows that the read_repair_chance=1.0. This also happens when creating the column family through Hector.
Going through the code, I find that in CfDef class, the constructor without any parameters sets the read_repair_chance to 1. Changing this value to 0.1 seems to create a column family with the 0.1 read_repair_chance. The best might be to remove it from the CfDef as the read_repair_chance is set to the default value in CFMetaDeta.