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. The monitoring frequency necessary to assess and assure compliance by the user with applicable pretreatment standards and requirements shall be indicated in the user’s control mechanism issued by the IPD.
(A) Except as indicated in divisions (B) and (C) below, the user must collect wastewater samples using 24-hour flow proportional composite collection techniques unless time-proportional composite sampling or grab sampling is authorized by the IPD. Where time-proportional composite sampling or grab sampling is authorized by the IPD, the samples must be representative of the discharge and the decision to allow the alternative sampling must be documented in the industrial user file for that facility or facilities. Using protocols (including appropriate preservation) specified in 40 C.F.R. Part 136 and appropriate EPA guidance, multiple grab samples collected during a 24-hour period may be composited prior to analysis as follows: for cyanide, total phenols, and sulfides the samples may be composited in the laboratory or 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 IPD, as appropriate. In addition, grab samples may be required to show compliance with instantaneous discharge limits.
(B) Samples for oil and grease, temperature, pH, cyanide, total phenols, sulfides, and volatile organic compounds must be obtained using grab collection techniques as specified in 40 C.F.R. Part 136.
(C) For sampling required in support of baseline monitoring and 90-day compliance reports required in §§ 53.095 and 53.097 of this subchapter, 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 IPD may authorize a lower minimum. For the reports required by § 53.098 (40 C.F.R. §§ 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 with applicable pretreatment standards and requirements.
(D) When 24-hour composite sampling is required, the composite sample must be taken within a 24-hour period, however this period only covers the period during which the industrial user is discharging.
(Prior Code, § 53.075) (Ord. 1590, passed 4-14-2009)