Section 310.605  Periodic Reports on Compliance

a)         After the compliance date of a pretreatment standard, or, in the case of a new source, after commencement of the discharge into the POTW, any industrial user subject to a categorical pretreatment standard (except a non-significant categorical user, as defined in Section 310.110) must submit to the Control Authority a report indicating the nature and concentration of pollutants in the effluent that are limited by the categorical pretreatment standards.  The industrial user must submit the report in June and December unless the Control Authority or the pretreatment standard requires more frequent reporting.  In addition, this report must include a record of measured or estimated average and maximum daily flows for the reporting period for the discharge reported in Section 310.602(d), except that the Control Authority may require more detailed reporting of flows.  If the pretreatment standard requires compliance with a best management practice (or pollution prevention alternative), the industrial user must submit documentation required by the Control Authority or the pretreatment standard necessary to determine the compliance status of the industrial user.  In consideration of such factors as local high or low flow rates, holidays, budget cycles, etc., the Control Authority may alter the months during which the reports required by this subsection (a) are to be submitted.  For an industrial user for which USEPA or the Agency is the Control Authority, as of December 21, 2025 or a USEPA-approved alternative date (see 40 CFR 127.24(e) or (f)), all reports submitted in compliance with this Subpart F must be submitted electronically by the industrial user to the Control Authority or initial recipient, as defined in Section 310.106(b)(2), in compliance with this Subpart F and Section 310.106.

b)         The Control Authority must authorize the industrial user subject to a categorical pretreatment standard to forego sampling of a pollutant regulated by a categorical pretreatment standard if it determines that the industrial user has demonstrated through sampling and other technical factors that the pollutant is neither present nor expected to be present in the discharge or that the pollutant is present only at background levels from intake water and without any increase in the pollutant due to activities of the industrial user.  This authorization is subject to the following conditions:

1)         The Control Authority may authorize a waiver only if it determines that a pollutant is present solely due to sanitary wastewater discharged from the facility, the sanitary wastewater is not regulated by an applicable categorical standard, and the sanitary wastewater otherwise includes no process wastewater;

2)         The monitoring waiver is valid only for the duration of the effective period of the permit or other equivalent individual control mechanism, but in no case longer than five years.  The industrial user must submit a new request for the waiver before the waiver can be granted for each subsequent control mechanism;

3)         In making a demonstration that a pollutant is not present, the industrial user must provide data from at least one sampling of the facility's process wastewater prior to any treatment present at the facility that is representative of all wastewater from all processes.  The request for a monitoring waiver must be signed in accordance with Section 310.631 and include the certification statement in Section 310.221(b)(2).  Non-detectable sample results may only be used as a demonstration that a pollutant is not present only if the USEPA-approved method from 40 CFR 136, incorporated by reference in Section 310.107, with the lowest minimum detection level for that pollutant was used in the analysis;

4)         Any grant of a monitoring waiver by the Control Authority must be included as a condition in the industrial user's control mechanism.  The reasons supporting the waiver and any information submitted by the industrial user in its request for the waiver must be maintained by the Control Authority for three years after the expiration of the waiver;

5)         Upon approval of the monitoring waiver and revision of the industrial user's control mechanism by the Control Authority, the industrial user must certify on each report with the statement below, that there has been no increase in the pollutant in its wastestream due to activities of the industrial user:

Based on my inquiry of the person or persons directly responsible for managing compliance with the pretreatment standard for Subpart [Subpart number of the applicable national pretreatment standard] of 35 Ill. Adm. Code 307, I certify that, to the best of my knowledge and belief, there has been no increase in the level of [list pollutants] in the wastewaters due to the activities at the facility since filing of the last periodic report under 35 Ill. Adm. Code 310.605(a);

6)         If a waived pollutant is found to be present or is expected to be present based on changes that occur in the industrial user's operations, the industrial user must immediately comply with the monitoring requirements of subsection (a) or other more frequent monitoring requirements imposed by the Control Authority, and the industrial user must notify the Control Authority; and

7)         This subsection (b) does not supersede certification processes and requirements established in categorical pretreatment standards, except as otherwise specified in the categorical pretreatment standard.

c)         If the Control Authority has imposed mass limitations on industrial users as provided by Section 310.232, the report required by subsection (a) must indicate the mass of pollutants regulated by pretreatment standards in the discharge from the industrial user.

d)         For industrial users subject to equivalent mass or concentration limits established by the Control Authority in accordance with the procedures in Section 310.230, the report required by subsection (a) must contain a reasonable measure of the user's long-term production rate.  For all other industrial users subject to categorical pretreatment standards expressed only in terms of allowable pollutant discharge per unit of production (or another measure of operation), the report required by subsection (a) must include the user's actual average production rate for the reporting period.

BOARD NOTE:  Derived from 40 CFR 403.12(e).

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