Mississippi Code Title 41. Public Health § 41-67-4

(1) The department shall determine the feasibility of establishing centralized wastewater treatment systems upon the submission by the developer of a preliminary design and feasibility study prepared by a licensed professional engineer. The developer may request and obtain a hearing before the board if the developer is dissatisfied with the department's determination of feasibility. The determination that a centralized wastewater treatment system must be established shall be made without regard to whether the establishment of a centralized wastewater treatment system is authorized by law or is subject to approval by one or more state or local government or public bodies. Whenever a developer requests a determination of feasibility, the department must make the determination within thirty (30) days after receipt of the preliminary design and feasibility study from the developer. The department shall state in writing the reasons for its determination. If the department does not make a determination within thirty (30) days, all sites within the subdivision shall be approved, if a certified installer attests or a department environmentalist determines that each site can be adequately served by an individual on-site wastewater disposal system.

(2) Where subdivisions are proposed that are composed of fewer than thirty-five (35) building sites, and no centralized wastewater treatment system is available, the department may waive the requirement for a feasibility study. If the feasibility study is waived, all sites within the subdivision shall be approved, if a certified installer attests or a department environmentalist determines that each site can be adequately served by an individual on-site wastewater disposal system.

(3) No feasibility study or centralized wastewater treatment system shall be required for subdivisions designed, laid out, platted or partially constructed before July 1, 1988, or for any subdivision that was platted and recorded during the period from July 1, 1995, through June 30, 1996.

(4) “Feasibility study” means a written evaluation and analysis of the potential of a proposed project that is based on investigation and research by a licensed professional engineer to give cost comparison between centralized or decentralized treatment and disposal and individual on-site wastewater disposal systems.