1. The commission, in consultation with the department, the department of health and each municipality located in whole or in part within the park, and subject to approval by the department and department of health, shall adopt, after public hearing according to the provisions of the state administrative procedure act, rules and regulations for the discharge of sewage or treated sewage effluent onto the land or into the groundwater of the park to ensure optimum protection of ground and surface waters within the park. Such rules and regulations may be more stringent than rules and regulations adopted by the department. For purposes of this section, the discharges shall include sewage or treated sewage effluent applied to the soil or entering the groundwater through runoff, seepage, percolation, spray irrigation and ground and spring water flow.

2. The rules and regulations adopted by the commission under subdivision one of this section shall be applicable to all development within the park with respect to the discharge of wastewater; provided, however, that nothing shall prevent a municipality from adopting a law, code, ordinance or regulation which is more stringent than such rules and regulations adopted by the commission.

3. The commission may delegate all or some of its authority under this section to any municipality located in whole or in part within the park subject to such conditions as the commission may establish.