California Code, Public Resources Code - PRC § 736

The board shall maintain its headquarters in Sacramento and shall hold meetings at such times and at such places as shall be determined by it.  Five members of the board shall constitute a quorum for the purpose of transacting any business of the board.  A majority affirmative vote of the total authorized membership of the board shall be necessary to adopt, amend, or repeal rules and regulations of the board adopted pursuant to Article 4 (commencing with Section 4551) of Chapter 8 of Part 2 of Division 4.  All meetings of the board shall be open to the public.