Mich. Admin. Code R. 323.1201
Rule 1201. The rules in this part shall be used to establish toxic substance water quality-based effluent limits (WQBELs) for point source discharges that are protective of the designated uses of the surface waters of the state as established in R 323.1100. WQBELs for certain toxic substances may be very low and in some cases less than what current analytical techniques can detect or quantify. In some effluents, the low levels may not be amenable to regulatory control through end-of-pipe treatment technology in a cost-effective manner. To achieve compliance with the low WQBELs and associated regulatory requirements, the department is committed to, and strongly encourages, the use of pollution prevention, source control, and other waste minimization programs. End-of-pipe treatment for the low WQBELs which is extraordinary or beyond that which would be necessary if not for the low WQBELs will not be required by the department unless it is determined to be the most cost-effective means or the only means to achieve the applicable water quality-based effluent limit. The provisions of R 323.1103 may provide an alternative to extraordinary end- of-pipe treatment where such treatment would result in unreasonable economic effects on the discharger. The rules of this part shall not be used as a basis for establishing controls on the discharge of toxic substances from intermittent wet-weather point sources.
Mich. Admin. Code R. 323.1201