567—62.6 (455B) Effluent limitations and pretreatment requirements for sources for which there are no federal effluent or pretreatment standards.
	 62.6(1) Definitions. As used in this rule:
	  a.   	 “Average” means the sum of the total daily discharges by weight, volume or concentration during the reporting period (as specified in the operation permit) divided by the total number of days during the reporting period when the facility was in operation. With respect to the monitoring requirements, the “daily average” discharge shall be determined by the summation of all the measured daily discharges by weight, volume or concentration divided by the number of days during the reporting period when the measurements were made.
	  b.   	 “Maximum” means the total discharge by weight, volume or concentration which cannot be exceeded during a 24-hour period.
	  c.   	 “Best engineering judgment” means a judgment that considers any or all of the following:
	 (1) 	 Known state-of-the-art (i.e., demonstrated treatment that is being done or can be done);
	 (2) 	 Published technical articles and research results;
	 (3) 	 Engineering reference books;
	 (4) 	 Consultation with acknowledged experts in the field;
	 (5) 	 Availability of equipment;
	 (6) 	 Known or suspected toxicity of the pollutants;
	 (7) 	 Safety, welfare and aesthetic effects on persons who may come in contact with the discharge; and
	 (8) 	 Standards and rules of other regulatory agencies and states.
	 62.6(2) Time of compliance. Effluent limitations and pretreatment limitations established pursuant to this rule shall be achieved within a reasonable time after receipt of notice from the department of the applicability of these limitations.
	 62.6(3) Effluent limitations. This subrule establishes effluent limitations on the discharge of pollutants from sources other than publicly owned treatment works and privately owned domestic sewage treatment works that are not subject to the federal effluent standards adopted by reference in 62.4(1) and 62.4(3) to 62.4(60).
	  a.   	 There shall be established an effluent limitation that represents the best engineering judgment of the department of the degree of effluent reduction consistent with the Act and Iowa Code chapter 455B.
	  b.   	 The following wastes shall not be introduced into privately owned treatment works subject to this subrule:
	 (1) 	 Wastes that create a fire or explosion hazard in the treatment works.
	 (2) 	 Wastes at a flow rate or pollutant discharge rate, or both, which is excessive over relatively short time periods so that there is a treatment process upset and subsequent loss of treatment efficiency such that the effluent limitations in the permit of the treatment works are violated.
	 62.6(4) Pretreatment requirements for incompatible wastes. This subrule establishes pretreatment requirements for incompatible pollutants that apply to sources other than those covered by 40 CFR §128.133, (i.e., sources other than existing “major contributing industries” as defined in 40 CFR §128.124), and to sources that are new or existing major contributing industries for which there is no federal pretreatment standard (i.e., sources which do not fall within a point source category or, if they do fall within a point source category, sources for which the administrator has not yet promulgated a pretreatment standard).
	  a.   	 For sources that are within a point source category adopted by reference in 62.4(455B) for which there are promulgated effluent limitation guidelines, but no promulgated pretreatment standards, the pretreatment standard for incompatible pollutants shall be the promulgated effluent limitation guideline. Provided, that if the treatment works which receives the pollutants is committed in its operation permit to remove a specified percentage of any incompatible pollutant, the pretreatment standard applicable to users of such treatment works shall be correspondingly reduced for that pollutant.
	  b.   	 For sources that are not subject to paragraph “a,” there shall be established an effluent limitation that represents the best engineering judgment in the department of the degree of effluent reduction consistent with the Act and Iowa Code chapter 455B.
	  c.   	 In no case shall a discharge into a publicly owned treatment works or a privately owned domestic sewage treatment works by a source subject to this subrule intermittently change the pH of the raw waste reaching the treatment plant by more than 0.5 pH unit or cause the pH of the waste reaching the plant to be less than 6.0 or greater than 9.0.