The twenty-one members of the commission shall be residents of the areas to which their membership is apportioned, and the total membership shall be divided among the participating counties as follows: 1. Richland County: nine members 2. Lexington County: six members 3. Newberry County: three members 4. Fairfield County: three members The membership from each county must be constituted as provided for in SECTION 43-39-30.