(A) All measurements, tests and analyses of the characteristics of waters and wastes to which reference is made in this chapter shall be determined in accordance with the latest edition of “Standard Methods for the Examination of Water and Wastewater,” published by the American Public Health Association, and shall be determined at the control manhole provided, or upon suitable samples taken at that control manhole. In the event that no special manhole has been required, the control manhole shall be considered to be the nearest downstream manhole in the public sewer to the point at which the building sewer is connected. Sampling shall be carried out by customarily accepted methods to reflect the effect of constituents upon sewage works and to determine the existence of hazards to life, limb and property. The particular analyses involved will determine whether a 24-hour composite of all outfalls of a premise is appropriate or whether a grab sample or samples should be taken. Normally, but not always, BOD and suspended solids analyses are obtained from 24-hour composites of all outfalls where pH's are determined from periodic grab samples.
(B) (1) Those industries determined to be major contributors as defined in the City's National Pollution Discharge Elimination System permit will be required to self monitor their effluents for the parameters and at the frequencies approved by the State Board of Health, Division of Industrial Wastes. The monitoring information will be submitted to the city on a monthly basis for inclusion in the city's quarterly industrial waste monitoring report to the state.
(2) A major contributing industry is one that has a flow of 50,000 gallons or more per average workday; has a flow greater than 5% of the flow carried by the municipal system receiving the waste; has in its waste a toxic pollutant in toxic amounts as defined in standards issued under Section 307(a) of the 1972 Federal Water Quality Act; or has significant impact, either singly or in combination with other contributing industries, on the treatment works or the quality of its effluent.
('71 Code, § 51.13) (Ord. 1278, passed 7-27-65; Am. Ord. 5-76, passed 7-12-76)