14.12.320 Sampling, analysis and flow measurements.
A. Periodic measurements of flow rates, flow volumes, BOD and suspended solids for use in determining the annual industrial wastewater treatment surcharge and such measurements of other constituents believed necessary by the city engineer shall be made by all industrial wastewater dischargers, unless specifically relieved of such obligation by the city engineer. All sampling, analyses and flow measurements of industrial wastewaters shall be performed by a state-certified independent laboratory, by a laboratory of an industrial discharger approved by the city engineer or by personnel of the city. Prior to submittal to the city of data developed in the laboratory of an industrial discharger, the results shall be verified by a responsible administrative official of the industrial discharger under the penalty of perjury.
B. All pollutant analyses, including sampling techniques, to be submitted as part of a wastewater discharge permit application or report shall be performed in accordance with the techniques prescribed in 40 CFR Part 136 and amendments thereto, unless otherwise specified in an applicable categorical pretreatment standard. Where 40 CFR Part 136 does not contain sampling or analytical techniques for the pollutant in question, or where the Regional EPA Administrator determines that the Part 136 sampling and analytical techniques are inappropriate for the pollutant in question, sampling and analysis shall be performed by using validated analytical methods or any other applicable sampling and analytical procedures, including procedures suggested by the city or other parties, approved by the Regional EPA Administrator. Any independent laboratory or discharger performing tests shall furnish any required test data or information on the test methods or equipment used, if requested to do so by the city engineer.
C. All dischargers making periodic measurements shall furnish and install at the control manhole or other appropriate location a calibrated flume, weir, flow meter or similar device approved by the city engineer and suitable to measure the industrial wastewater flow rate and total volume. A flow indicating, recording and totalizing register may be required by the city engineer in lieu of wastewater flow measurement, the city engineer may accept records of water usage and adjust the flow volumes by suitable factors to determine peak and average flow rates for the specific industrial wastewater discharge.
D. The sampling, analysis and flow measurement procedures, equipment and results shall be subject at any time to inspection by the city. Sampling and flow measurement facilities shall be such as to provide safe access to authorized personnel.
E. Those industrial wastewater dischargers required by the city engineer to make periodic measurements of industrial wastewater flows and constituents shall annually make the minimum number of such measurements required. The minimum requirement for such periodic measurements shall be at least two twenty-four-hour measurements per year. Representative samples of the industrial wastewater shall be obtained at least once per hour over the twenty-four-hour period, properly refrigerated, composited according to measured flow rates during the twenty-four hours and analyzed for the specified wastewater constituents.
Dischargers required to sample on only a few days per year shall sample during the periods of highest wastewater flow and wastewater constituent discharges. Industrial plants with large fluctuations in quantity or quality of wastewater may be required to provide continuous sampling and analyses for every working day. When required by the city engineer, dischargers shall install and maintain in proper order automatic flow proportional sampling equipment and/or automatic analysis and recording equipment.
F. Measurements to verify the quantities of waste flows and waste constituents reported by industrial dischargers will be conducted on a random basis by personnel of the city.
G. Each industrial discharger, including those subject to self-monitoring and reporting requirements, shall retain for a minimum of three years records of monitoring activities and results required by this chapter, including documentation associated with best management practices established under Section 14.12.220(B)(22), and shall make such records available upon request for inspection and copying by inspectors and other authorized personnel of the city acting pursuant to Section 14.12.100 or otherwise pursuant to this chapter. Such records shall be retained during the pendency of any litigation regarding industrial discharge or for such additional periods as may be requested by county, state or federal entities.
H. Samples collected to satisfy reporting requirements must be based on data obtained through appropriate sampling and analysis performed during the period covered by the report, based on data that is representative of conditions occurring during the reporting period.
1. Except as indicated in subsections 2 and 3 below, the user must collect wastewater samples using twenty-four-hour flow-proportional composite sampling techniques, unless time-proportional composite sampling or grab sampling is authorized by the city. Where time-proportional composite sampling or grab sampling is authorized by the city, the samples must be representative of the discharge. Using protocols (including appropriate preservation) specified in 40 CFR Part 136 and appropriate EPA guidance, multiple grab samples collected during a twenty-four-hour period may be composited prior to the analysis as follows: for cyanide, total phenols, and sulfides the samples may be composited in the laboratory or in the field; for volatile organics and oil and grease, the samples may be composited in the laboratory. Composite samples for other parameters unaffected by the compositing procedures as documented in approved EPA methodologies may be authorized by the city, as appropriate. In addition, grab samples may be required to show compliance with instantaneous limits.
2. Samples for oil and grease, temperature, pH, cyanide, total phenols, sulfides, and volatile organic compounds must be obtained using grab collection techniques.
3. For sampling required in support of baseline monitoring and ninety-day compliance reports required in Section 14.12.325(A) and (C) [40 CFR 403.12(b) and (d)], a minimum of four grab samples must be used for pH, cyanide, total phenols, oil and grease, sulfide and volatile organic compounds for facilities for which historical sampling data do not exist; for facilities for which historical sampling data are available, the city may authorize a lower minimum. For the reports required by Section 14.12.325(D) (40 CFR 403.12(e) and (h)), the industrial user is required to collect the number of grab samples necessary to assess and assure compliance by with applicable pretreatment standards and requirements. (Ord. 4740 § 1, 2013; Ord. 3667 § 1, 1995)