Section 310.610  Monitoring and Analysis

a)         Except in the case of a non-significant categorical user, the reports required in Sections 310.602(e), 310.604, 310.605, and 310.611 must contain the results of sampling and analysis of the discharge, including the flow and the nature and concentration, or production and mass if requested by the Control Authority, of pollutants contained in the discharge that are limited by the applicable pretreatment standards. This sampling and analysis may be performed by the Control Authority instead of the industrial user. If the POTW performs the required sampling and analysis instead of the industrial user, the user is not required to submit the compliance certification required under Sections 310.602(f) and 310.604.  In addition, if the POTW itself collects all the information required for the report, including flow data, the industrial user is not required to submit the report.

b)         If sampling performed by an industrial user indicates a violation, the user must notify the Control Authority within 24 hours after becoming aware of the violation.  The user must also repeat the sampling and analysis and submit the results of the repeat analysis to the Control Authority within 30 days after becoming aware of the violation.  If the Control Authority has performed the sampling and analysis in lieu of the industrial user, the Control Authority must perform the repeat sampling and analysis, unless it notifies the industrial user of the violation and requires the industrial user to perform the repeat analysis.  Resampling is not required if the following conditions are fulfilled:

1)         The Control Authority performs sampling at the industrial user at a frequency of at least once per month; or

2)         The Control Authority performs sampling at the user between the time when the initial sampling was conducted and the time when the industrial user or the Control Authority receives the results of this sampling.

c)         The reports required in Sections 310.602, 310.604, 310.605, and 310.611 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 Control Authority must require the 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 Control Authority.  If time-proportional composite sampling or grab sampling is authorized by the Control Authority, 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 136, incorporated by reference in Section 310.107(b), and appropriate USEPA 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 the compositing procedures as documented in USEPA-approved methodologies may be authorized by the Control Authority, as appropriate.

d)         For sampling required in support of baseline monitoring and 90-day compliance reports required in Sections 310.602 and 310.604, 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 Control Authority may authorize a lower minimum.  For the reports required by Sections 310.605 and 310.611, the Control Authority must require the number of grab samples necessary to assess and assure compliance by industrial users with applicable pretreatment standards and requirements.

e)         All analyses must be performed in accordance with procedures referenced in 35 Ill. Adm. Code 307.1003, or with any other test procedure approved by the Agency.  Sampling must be performed in accordance with the techniques approved by the Agency.  If 35 Ill. Adm. Code 307.1003 does not reference sampling or analytical techniques for the pollutants in question or USEPA has determined as provided in Section 310.602 that sampling and analytical techniques are inappropriate, sampling and analyses must be performed using validated analytical methods or any other sampling and analytical procedures including procedures approved by the POTW or other persons.

f)         If an industrial user subject to the reporting requirement in Section 310.605 monitors any regulated pollutant at the appropriate sampling location more frequently than required by the Control Authority, using the procedures prescribed in subsection (e), the results of this monitoring must be included in the report.

BOARD NOTE:  Derived from 40 CFR 403.12(g) (2005), as amended at 70 Fed. Reg. 60134 (Oct. 14, 2005).

(Source:  Amended at 47 Ill. Reg. 5083, effective March 23, 2023)