Section 611.979  Reporting and Recordkeeping Requirements

a)         Reporting

1)         A supplier must report the following information to the Agency within ten days after the end of any quarter in which monitoring is required for each monitoring location:

A)        The number of samples taken during the last quarter;

B)        The date and results of each sample taken during the last quarter;

C)        The arithmetic average of quarterly results for the last four quarters for each monitoring location (LRAA), beginning at the end of the fourth calendar quarter that follows the compliance date and at the end of each subsequent quarter.  If the LRAA calculated based on fewer than four quarters of data would cause the MCL to be exceeded regardless of the monitoring results of subsequent quarters, the supplier must report this information to the Agency as part of the first report due following the compliance date or anytime thereafter that this determination is made.  If the supplier is required to conduct monitoring at a frequency that is less than quarterly, it must make compliance calculations beginning with the first compliance sample taken after the compliance date, unless the supplier is required to conduct increased monitoring under Section 611.975;

D)        A statement whether, based on Section 611.312(b)(2) and this Subpart Y, the MCL was violated at any monitoring location; and

E)        Any operational evaluation levels that were exceeded during the quarter and, if so, the location and date, and the calculated TTHM and HAA5 levels.

2)         If a supplier is a Subpart B system supplier that seeks to qualify for or remain on reduced TTHM and HAA5 monitoring, it must report the following source water TOC information for each treatment plant that treats surface water or groundwater under the direct influence of surface water to the Agency within ten days after the end of any quarter in which monitoring is required:

A)        The number of source water TOC samples taken each month during last quarter;

B)        The date and result of each sample taken during last quarter;

C)        The arithmetic average of monthly samples taken during the last quarter or the result of the quarterly sample;

D)        The running annual average (RAA) of quarterly averages from the past four quarters; and

E)        Whether the RAA exceeded 4.0 mg/ℓ.

3)         The Agency may, by a SEP, choose to perform calculations and determine whether the MCL was exceeded or the system is eligible for reduced monitoring in lieu of having the system report that information under this Section.

b)         Recordkeeping.  A supplier must retain any Subpart Y monitoring plans and the supplier's Subpart Y monitoring results as required by Section 611.860.

BOARD NOTE:  Derived from 40 CFR 141.629.

(Source:  Amended at 44 Ill. Reg. 6996, effective April 17, 2020)