(a) The Board in its discretion may submit the following for publication in the Illinois Register as it deems appropriate: (1) a regulatory agenda to solicit comments concerning any rule that the Board is considering for proposal, but for which no notice of rulemaking activity has been submitted to the Illinois Register;(2) notices of all petitions for individual adjusted standards that have been filed with the Board;(3) notices of all public hearings to be held by the Board, including any hearings scheduled by the Board for consideration of an individual adjusted standard petition;(4) the results of Board determinations concerning the necessity for economic impact studies;(5) restricted status lists, on a quarterly basis; and(6) any other documents related to the activities of the Pollution Control Board that the Board deems appropriate for publication.(b) The Board shall publish the following in the Illinois Register:(1) pursuant to Section 5-40 of the Illinois Administrative Procedure Act, notice of all proposed regulations;(2) pursuant to Sections 5-45 and 5-50 of the Illinois Administrative Procedure Act, notice of all emergency and peremptory regulations; and(3) the results of Board determinations concerning adjusted standards proceedings.