The Board shall meet at least once every three months and at such other times, on the call of the chairman or of a majority of the members, as may be deemed necessary to transact such business as may properly be brought before it. Six members shall constitute a quorum of the Board for all purposes. For a transportation project valued in excess of $25 million that is located wholly within a single highway construction district, the Board shall hold at least one hearing in the highway construction district where such project being considered is located to discuss such project prior to a meeting at which a vote to program funds pursuant to § 33.2-214 for such project will be taken. It shall be the duty of the Board to keep accurate minutes of all meetings of the Board, in which shall be set forth all acts and proceedings of the Board in carrying out the provisions of this title.