(1) Not less than fifteen calendar days after a hearing has been requested as provided in this article, the commission shall grant such request and set a time and place therefor not more than ninety calendar days following receipt of such request, unless a shorter period is otherwise specifically provided for in this article. Notice of such hearing shall be printed in a newspaper of general circulation in the area in which the proposed project or activity is located at least thirty days prior to the date of said hearing.

(2) The division shall appear as a party in any hearing before the commission and shall have the same rights to judicial review as any other party.

(2.5) The division or the federal environmental protection agency, or both, may appear as parties pursuant to subsection (5) of this section in any hearing before the commission. The federal environmental protection agency is encouraged to participate in the hearing process early and often so that its interpretations are heard. If the federal environmental protection agency does not comply with the provisions of this subsection (2.5), the commission may not receive evidence from such agency in any hearing related to stationary sources conducted pursuant to this section, and any subsequent opinions by such agency shall carry no weight before the commission or in any judicial proceeding.

(3) All testimony taken at any such hearing before the commission shall be under oath or affirmation. A full and complete record of all proceedings and testimony presented shall be taken and filed. The stenographer shall furnish, upon payment and receipt of any fees allowed therefor, a certified transcript of the whole or any part of the record to any party in such hearing requesting the same.

(4) Any information relating to secret processes or methods of manufacture or production which may be required, ascertained, or discovered shall not be publicly disclosed in public hearings or otherwise and shall be kept confidential by any member, officer, or employee of the commission or the division. Any person seeking to invoke the protection of this subsection (4) in any hearing shall bear the burden of proving its applicability. Except as provided in the federal act, information claimed to be related to secret processes or methods of manufacture or production but which constitutes emission data may not be withheld as confidential; except that such information may be submitted under a claim of confidentiality, and the division shall not disclose any such information to the public unless required under the federal act.

(5) At any hearing, any person who is affected by the proceeding and whose interests are not already adequately represented shall have the opportunity to be a party thereto upon prior application to and approval by the commission in its sole discretion, as deemed reasonable and proper by said commission, and such person shall have the right to be heard and to cross-examine any witness.

(6) After due consideration of the written and oral statements, the testimony, and the arguments presented at any such hearing, the commission shall make its findings and order, based upon evidence in the record, or make such determination of the matter as it shall deem appropriate, consistent with the provisions of this article and any rule, regulation, or determination promulgated by the commission pursuant thereto. Unless a time period is otherwise specifically provided for in this article, such finding and order or determination shall be made within thirty calendar days after the completion of such hearing.

(7) In all proceedings before the commission with respect to any alleged violation of any provision of this article, regulation of the commission, order or permit or terms or conditions thereof, or requirement of the state implementation plan, the burden of proof shall be upon the division.

(8) The applicant for a permit or delayed compliance order, or any modification thereof, and the petitioner for any amendment to the state implementation plan shall bear the burden of proof with respect to the justification therefor and the information, data, and analysis supportive thereof or required with respect to such application or petition.

(9) Repealed.

(10) Every hearing granted by the commission shall be conducted by the commission, and every hearing shall comply with the provisions of this article and the provisions of article 4 of title 24, C.R.S.