A distribution box shall be provided to receive the effluent from the septic tank to assure equal distribution to each individual line of the disposal field as shown in § 53.075(D), in accordance with the following items.
   (A)   Connection. The distribution box should be connected to a septic tank by a tight sewer (cast iron with mechanical joints) lines and be located at the upper end of the disposal field.
   (B)   Invert level. The invert of the inlet pipe should be located six inches above the bottom of the box. The invert of the lets to each distribution line should be located four inches above the bottom of the box and set at the same elevation.
   (C)   Inspection. The sides of the box should extend to within a short distance of the ground surface to permit inspection. The box should be kept to the minimum size necessary to accommodate the inlet and outlets.
(1975 Code, § 38.37)