(1) A person who is registered as a waste water specialist under ORS 700.053 shall not perform the duties of a registered environmental health specialist, except that the person may:
(a) Evaluate soils for subsurface or surface disposal of waste water or for the land application of sludge; and
(b) Based on the soil evaluation, determine the appropriate design of systems that use soil in the final stage of the waste water treatment process.
(2) This section does not prohibit a registered environmental health specialist from performing the duties of a waste water specialist.