All measurements, tests, sampling and analysis of the characteristics of wastewaters discharged to the city’s wastewater facilities shall be determined in accordance with rules, specified in 40 C.F.R. pt. 136, or in the absence of 40 C.F.R. pt. 136 methods, by methods contained in the latest edition of Standard Methods of Examination of Water and Wastewater, as published by the American Public Health Association, and shall be determined at the location designated by the Public Works Director or designee.