1. No standard, rule or regulation or any amendment or repeal thereof shall be adopted except after a public hearing to be held after thirty days’ prior notice by advertisement of the date, time and place of the hearing and opportunity given to the public to be heard. Notice of the hearings and copies of the proposed standard, rule or regulation or any amendment or repeal thereof shall also be given by regular mail, at least thirty days prior to the scheduled date of the hearing, to any person who has registered with the director for the purpose of receiving notice of such public hearings in accordance with the procedures prescribed by the commission at least forty-five days prior to the scheduled date of the hearing. However, this provision shall not preclude necessary changes during this thirty-day period.

2. At the hearing, opportunity to be heard by the commission with respect to the subject thereof shall be afforded any interested person upon written request to the commission, addressed to the director, not later than seven days prior to the hearing, and may be afforded to other persons if convenient. In addition, any interested persons, whether or not heard, may submit, within seven days subsequent to the hearings, a written statement of their views. The commission may solicit the views, in writing, of persons who may be affected by, or interested in, proposed rules and regulations, or standards. Any person heard or represented at the hearing or making written request for notice shall be given written notice of the action of the commission with respect to the subject thereof.

3. Any standard, rule or regulation or amendment or repeal thereof shall not be deemed adopted or in force and effect until it has been approved in writing by at least four members of the commission. A standard, rule or regulation or an amendment or repeal thereof shall not become effective until a certified copy thereof has been filed with the secretary of state as provided in chapter 536.

4. Unless prohibited by any federal water pollution control act, any standard, rule or regulation or any amendment or repeal thereof which is adopted by the commission may differ in its terms and provisions as between particular types and conditions of water quality standards or of water contaminants, as between particular classes of water contaminant sources, and as between particular waters of the state.

5. Any listing required by Section 303(d) of the federal Clean Water Act, as amended, 33 U.S.C. § 1251, et seq., to be sent to the U.S. Environmental Protection Agency for its approval that will result in any waters of the state being classified as impaired shall be adopted by the commission after a public hearing, or series of hearings, held in accordance with the following procedures. The department of natural resources shall publish in at least six regional newspapers, in advance, a notice by advertisement the availability of a proposed list of impaired waters of the state and such notice shall include at least ninety days’ advance notice of the date, time, and place of the public hearing and opportunity given to the public to be heard. Notice of the hearings and copies of the proposed list of impaired waters also shall be posted on the department of natural resources’ website and given by regular mail, at least ninety days prior to the scheduled date of the hearing, to any person who has registered with the director for the purpose of receiving notice of such public hearings. The proposed list of impaired waters shall identify the water segment, the uses to be made of such waters, the uses impaired, identify the pollutants causing or expected to cause violations of the applicable water quality standards, and provide a summary of the data relied upon to make the preliminary determination. Contemporaneous with the publication of the notice of public hearing, the department shall make available on its website all data and information it relied upon to prepare the proposed list of impaired waters, including a narrative explanation of how the department determined the water segment was impaired. At any time after the public notice and until seven days after the public hearing, the department shall accept written comments on the proposed list of impaired waters. After the public hearing and after all written comments have been submitted, the department shall prepare a written response to all comments and a revised list of impaired waters. The commission shall adopt a list of impaired waters in a public meeting during which the public shall be afforded an opportunity to respond to the department’s written response to comments and revised list of impaired waters. Notice of the meeting shall include the date, time, and place of the public meeting and shall provide notice that the commission will give interested persons the opportunity to respond to the department’s revised list of impaired waters and written responses to comments. At its discretion, the commission may extend public comment periods or hold additional public hearings on the proposed and revised lists of impaired waters. The commission shall not vote to add to the list of impaired waters any waters not recommended by the department in the proposed or revised lists of impaired waters without granting the public at least thirty additional days to comment on the proposed addition. The list of impaired waters adopted by the commission shall not be deemed to be a rule as defined by section 536.010. The listing of any water segment on the list of impaired waters adopted by the commission shall be subject to judicial review by any adversely affected party under section 536.150.