Ill. Admin. Code tit. 35, § 611.745 - Reporting and Recordkeeping Requirements

In addition to the reporting and recordkeeping requirements in Sections 611.261 and 611.262, a PWS supplier subject to the requirements of this Subpart R that provides conventional filtration treatment or direct filtration must report monthly to the Agency the information specified in subsections (a) and (b). In addition to the reporting and recordkeeping requirements in Sections 611.261 and 611.262, a PWS supplier subject to the requirements of this Subpart R that provides filtration approved under Section 611.743(b) must report monthly to the Agency the information specified in subsection (a). The reporting in subsection (a) is in lieu of the reporting specified in Section 611.262(a).

a) Turbidity measurements, as required by Section 611.743, must be reported within ten days after the end of each month the system serves water to the public. Information that must be reported is the following:

1) The total number of filtered water turbidity measurements taken during the month.

2) The number and percentage of filtered water turbidity measurements taken during the month that are less than or equal to the turbidity limits specified in Section 611.743(a) or (b).

3) The date and value of any turbidity measurements taken during the month that exceed 1 NTU for a supplier using conventional filtration treatment or direct filtration, or that exceed the maximum level under Section 611.743(b).

b) A supplier must maintain the results of individual filter monitoring taken under Section 611.744 for at least three years. A supplier must report that it has conducted individual filter turbidity monitoring under Section 611.744 within ten days after the end of each month the system serves water to the public. A supplier must report individual filter turbidity measurement results taken under Section 611.744 within ten days after the end of each month the supplier serves water to the public only if measurements demonstrate one or more of the conditions in subsections (b)(1) through (b)(4). A supplier that uses lime softening may apply to the Agency for alternative exceedance levels for the levels specified in subsections (b)(1) through (b)(4) if they can demonstrate that higher turbidity levels in individual filters are due to lime carryover only and not due to degraded filter performance.

1) For any individual filter that has a measured turbidity level of greater than 1.0 NTU in two consecutive measurements taken 15 minutes apart, the supplier must report the filter number, the turbidity measurement, and the dates on which the exceedance occurred. In addition, the supplier must either produce a filter profile for the filter within seven days after the exceedance (if the supplier is not able to identify an obvious reason for the abnormal filter performance) and report that the profile has been produced or report the obvious reason for the exceedance.

2) For any individual filter that has a measured turbidity level of greater than 0.5 NTU in two consecutive measurements taken 15 minutes apart at the end of the first four hours of continuous filter operation after the filter has been backwashed or otherwise taken offline, the supplier must report the filter number, the turbidity, and the dates on which the exceedance occurred. In addition, the supplier must either produce a filter profile for the filter within seven days after the exceedance (if the supplier is not able to identify an obvious reason for the abnormal filter performance) and report that the profile has been produced or report the obvious reason for the exceedance.

3) For any individual filter that has a measured turbidity level of greater than 1.0 NTU in two consecutive measurements taken 15 minutes apart at any time in each of three consecutive months, the supplier must report the filter number, the turbidity measurement, and the dates on which the exceedance occurred. In addition, the supplier must conduct a self-assessment of the filter within 14 days after the exceedance and report that the self-assessment was conducted. The self-assessment must consist of at least the following components: assessment of filter performance; development of a filter profile; identification and prioritization of factors limiting filter performance; assessment of the applicability of corrections; and preparation of a filter self-assessment report.

4) For any individual filter that has a measured turbidity level of greater than 2.0 NTU in two consecutive measurements taken 15 minutes apart at any time in each of two consecutive months, the supplier must report the filter number, the turbidity measurement, and the dates on which the exceedance occurred. In addition, the supplier must arrange for the conduct of a comprehensive performance evaluation by the Agency or a third party approved by the Agency no later than 30 days following the exceedance and have the evaluation completed and submitted to the Agency no later than 90 days following the exceedance.

c) Additional Reporting Requirements

1) If at any time the turbidity exceeds 1 NTU in representative samples of filtered water in a system using conventional filtration treatment or direct filtration, the supplier must consult with the Agency as soon as possible, but no later than the end of the next business day.

2) If at any time the turbidity in representative samples of filtered water exceeds the maximum level set by the Agency under Section 611.743(b) for filtration technologies other than conventional filtration treatment, direct filtration, slow sand filtration, or diatomaceous earth filtration, the supplier must inform the Agency as soon as possible, but no later than the end of the next business day.

Notes

Ill. Admin. Code tit. 35, § 611.745

Amended at 27 Ill. Reg. 16447, effective October 10, 2003

Amended at 39 Ill. Reg. 15352, effective 11/13/2015 Amended at 42 Ill. Reg. 1140, effective 1/4/2018 Amended at 44 Ill. Reg. 6996, effective 4/17/2020

BOARD NOTE: Derived from 40 CFR 141.175.