Section 2091.5-6 - Congressional withdrawals and opening of lands(a) Congressional withdrawals become effective and are terminated as specified in the statute making the withdrawal. If the statute does not specify the date, duration and extent of segregation, the Secretary shall publish in the FEDERAL REGISTER a Public Land Order so specifying.(b) If the statute does not specify when and to what extent the lands are to be opened, the Secretary publishes in the FEDERAL REGISTER an opening order so specifying.