A. Samples collected to satisfy reporting requirements must be based on data obtained through appropriate sampling and analyses performed during the period covered by the report and be representative of conditions occurring during the reporting period.

B. Except as indicated in subsections C and D below, the IU 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 director. Where time proportional composite sampling or grab sampling is authorized by the director, 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.

C. Samples for oil and grease, temperature, pH, cyanide, total phenols, sulfides, and volatile organic compounds must be obtained using grab collection techniques.

D. For sampling required in support of baseline monitoring reports and ninety-day compliance reports pursuant to Sections 13.08.170 and 13.08.510 (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 director may authorize a lower minimum. For the reports required by Section 13.08.200 (40 CFR 403.12(e) and (h)), the IU is required to collect the number of grab samples necessary to assess and assure compliance with applicable pretreatment standards and requirements.

E. If an IU subject to the reporting requirement in this section monitors any regulated pollutant at the appropriate sampling location more frequently than required by the director, using the procedures set forth in Section 13.08.270, the results of this monitoring shall be included in the report.

F. All required sampling shall be done at the IU’s expense. (Ord. 1598 § 1 (part), 2014)