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.
(a) Except as indicated in Section (b) and (c) below, the User must collect Wastewater Discharge samples using 24-hour flow proportional Composite Sample techniques, unless a time proportional Composite Sample or Grab Sample is authorized by the Director or specified in a WDP. Where a time proportional Composite Sample or Grab Sample is authorized by the Director, the sample(s) 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 24-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 Non Polar FOG, 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 in writing, as appropriate. In addition, Grab Samples may be required to show compliance with Instantaneous Limits.
(b) Samples for Non Polar FOG, temperature, pH, cyanide, total phenols, sulfides, dissolved hexavalent chromium, and volatile organic compounds must be obtained using Grab Sample techniques.
(c) For sampling required in support of baseline monitoring and 90-day compliance reports required in Section 915.34 and 915.36, a minimum of four (4) Grab Samples must be used for pH, cyanide, total phenols, Polar and Non Polar FOG, 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 915.37 (40 CFR 403.12 (e) and 403.12 (h), the Industrial User is required to collect the number of grab samples necessary to assess and assure compliance by the User with applicable Pretreatment Standards and Requirements.
(Ord. 2015-81. Passed 4-15-15.)