Senate committee substitute makes the following changes to the 3rd edition.

Modifies the membership of the On-Site Wastewater Task Force (Task Force) as follows. Removes the qualification that members are appointed. Now provides for a representative of rather than a member from each of the following: the NC Division of Public Health, On-Site Water Protection Branch; the NC Environmental Heath Supervisors Association; the NC Home Builders Association; the NC On-Site Wastewater Contractor Inspector Certification Board; the NC Septic Tank Association; the Consulting Soil Scientists Association of North Carolina; the NC Board of Examiners for Engineers and Surveyors with specified experience; and the NC Board for Licensing of Soil Scientists. Further specifies that representatives of the Consulting Soil Scientists Association of North Carolina and the NC Board for Licensing of Soil Scientists must have experience conducting private consultative services of sites evaluated for on-site wastewater systems. Adds to the membership a person currently certified as a Water Pollution Control Systems Operator and actively conducting business as an operator of on-site wastewater systems (replacing a member from the Department of Environmental Quality) and a representative of the NC Licensing Board for General Contractors (replacing a member from the Carolinas Association of General Contractors). 

More specifically establishes that the specified administrative rules regarding the treatment and disposal of domestic type sewage will remain in effect until replacement rules adopted by the Commission for Public Health become effective. Exempts the specified rules from the periodic review and expiration of existing rules process required by state law. 

Provides that the specified administrative rules regarding on-site wastewater treatment and dispersal adopted by the Commission for Public Health on August 8, 2018, and approved by the Rules Review Commission will not become effective if the enumerated rules of the act are in fact disapproved. 

Amends GS 130A-343, concerning the approval of on-site surface water systems. Modifies the definition of accepted wastewater dispersal system to include a wastewater dispersal system specifically identified in a rule adopted by the Public Health Commission (rather than other approved trench dispersal systems by the Department of Environmental Quality) meeting the existing criteria. Makes further conforming and technical changes. Concerning the Public Health Commission's designation of a wastewater dispersal system as an accepted wastewater dispersal system, requires the Commission to make the previously specified findings based on clear, convincing, and cogent evidence based on actual field surveys and county activity reports (previously, did not specify the bases for the evidence).

Modifies proposed GS 130A-336.2 by eliminating the provision which restricted a wastewater system owner's remedies against authorized on-site wastewater evaluators, certified contractors, and certified pollution control systems operators to the remedies provided in the laws and rules governing each individual profession.

Amends the act's short title.