SECTION 252:623-11-7. Sample collection

(a)   Permit applications required by OAC 252:623-7-4 and periodic compliance reports required by OAC 252:623-11-1 must be based upon data obtained through appropriate sampling and analysis performed during the period covered by the report, which data are representative of conditions occurring during the reporting period. The DEQ shall require that frequency of monitoring necessary to assess and assure compliance by Industrial Users with applicable Pretreatment Standards and Requirements. Grab samples must be used for pH, cyanide, total phenols, oil and grease, sulfide, and volatile organic compounds. For all other pollutants, 24-hour composite samples must be obtained through flow-proportional composite sampling techniques, unless time-proportional composite sampling or grab sampling is authorized by the DEQ. Where time-proportional composite sampling or grab sampling is authorized by the DEQ, 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 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 & 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 DEQ, as appropriate.

(b)   If an Industrial User subject to the reporting requirements in 252:623-11-1 monitors any pollutant(s) at the appropriate sampling location more frequently than required by the DEQ, using the procedures prescribed in 252:623-11-6, the results of all such monitoring shall be included in the report.

[Source: Added at 18 Ok Reg 1601, eff 6-1-01; Amended at 24 Ok Reg 1535, eff 6-15-07]