(a) Any person or other entity discharging effluents is relieved of the requirements for such effluents contained in section 550.2(e)(3) and (4) of this Part if at all times of the year the waters into which the discharge enters meet the requirements of section 550.2(c) of this Part. The foregoing applies only if the discharger who is discharging biochemical oxygen demand or total suspended solids or both has a permit from the United States Environmental Protection Agency or the State pursuant to section 402 of the Federal Water Pollution Control Act amendments of 1972 (33 USC 1342), which permit has requirements or limitations relating to discharge of biochemical oxygen demand, total suspended solids, or both, as the case may be, and the discharger is complying with those requirements or limitations.

(b) Nothing in these regulations shall be construed to encourage or give the sanction of the Interstate Environmental Commission to the degradation of any waters which are of a quality consistent with these regulations. Accordingly, it is the responsibility of any discharger determining that he will proceed under these variance provisions to plan and operate his facilities and processes with due regard for present and changing conditions of, and affecting the waters in, his area. It shall not be a defense to a violation that the discharger did not anticipate or was not aware of changes which have resulted in the applicability of section 550.2(e)(3) and (4) of this Part, to his effluent discharge.