(A) Samples collected to satisfy reporting requirements of the permit shall be representative of the user’s discharge and obtained through appropriate sampling techniques. The data analysis of the samples collected shall be performed during the period covered by the report, based on data that is representative of conditions occurring during the reporting period.
(B) Except as indicated in divisions (C) and (D) below, the user shall collect wastewater samples using 24-hour flow proportional composite collection techniques. In the event flow proportional sampling is not feasible, the Superintendent may authorize, in writing, the use of time proportional sampling or a minimum of four grab samples where the user demonstrates that this will provide a representative sample of the effluent being discharged. 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 oil and grease, the samples may be composited in the laboratory. Composite samples for other parameters unaffected by composting procedures as documented in approved EPA methodologies may be authorized by the Superintendent, as appropriate. In addition, grab samples may be required to show compliance with instantaneous discharge limits.
(C) Samples for oil and grease, temperature, pH, cyanide, phenols, sulfides, and volatile organic compounds shall be obtained using grab collection techniques.
(D) Samples for monitoring compliance by categorical industries should be taken immediately downstream from the pretreatment facilities if such facilities exist or immediately downstream from the regulated process if no pretreatment facilities exist. If other wastewaters are mixed with the regulated wastewater prior to treatment, the user should measure the flows and concentration necessary to allow use of the combined waste stream in order to evaluate compliance with pretreatment standards. When an alternate concentration or mass limit has been calculated this adjusted limit along with the supporting data shall be submitted to the Superintendent.
(E) For sampling required in support of baseline monitoring and 90-day compliance reports required by this chapter and 40 C.F.R. 403.12(b) and (d), a minimum of four grab samples shall 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 Superintendent may authorize, in writing, a lower minimum number of samples. For the reports required by this chapter and 40 C.F.R. 403.12(e) and (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.
(Ord. 1476, passed 6-18-07; Am. Ord. 1531, passed 8-16-10; Am. Ord. 1639, passed 12-19-16) Penalty, see § 52.999