(a) Any seepage pit, drainage field or other leaching facility receiving any form of household effluent, regardless of whether it receives toilet wastes, is subject to the sewage disposal system setback restrictions.

(b) Any outhouse privy or other pit privy which is not a self-contained system is subject to the sewage disposal system setback restrictions.

(c) Any lawfully existing onsite wastewater treatment system which is in non-conformance with the agency shoreline setback requirements, when proposed to be replaced, must be replaced in conformance with the setback requirements to the greatest extent possible, and in any case, no closer to the mean high water mark. No variance will be required for a replacement system which meets this requirement and which will also provide enhanced treatment over the lawfully existing system as determined by the agency, provided such system is not also being expanded to meet an actual or potential occupancy increase.

(d) Any proposed expansion of a non-conforming onsite wastewater treatment system designed to service an actual or potential increase in occupancy of the shoreline structure served must meet all existing standards for such systems, including the shoreline setback requirements. Otherwise, a variance will be required for the system expansion.