Section 611.261  Unfiltered PWSs:  Reporting and Recordkeeping

A supplier using a groundwater source under the direct influence of surface water not providing filtration treatment must report monthly to the Agency the information this Section specifies beginning six months after the Agency determines that the groundwater source is under the direct influence of surface water.  When the Agency issues a SEP requiring filtration treatment and specifying appropriate alternative reporting requirements until the supplier applies filtration treatment.

a)         The supplier must report source water quality information to the Agency within ten days after the end of each month the supplier serves water to the public. The information must include certain information:

1)         The cumulative number of months for which the supplier reports results.

2)         The number of fecal or total coliform samples, whichever the supplier analyzed during the month (if a supplier monitors for both, the supplier needs only report fecal coliform samples), the dates the supplied collected the samples, and the dates when the turbidity level exceeded 1 NTU.

3)         The number of samples during the month that had equal to or fewer than 20/100 ml fecal coliforms or equal to or fewer than 100/100 ml total coliforms, whichever the supplier analyzed.

4)         The cumulative number of fecal or total coliform samples, whichever the supplier analyzed, during the previous six months the supplier served water to the public.

5)         The cumulative number of samples that had equal to or fewer than 20/100 ml fecal coliforms or equal to or fewer than 100/100 ml total coliforms, whichever the supplier analyzed, during the previous six months the supplier served water to the public.

6)         The percentage of samples that had equal to or fewer than 20/100 ml fecal coliforms or equal to or fewer than 100/100 ml total coliforms, whichever the supplier analyzed, during the previous six months the supplier served water to the public.

7)         The maximum turbidity level the supplier measured during the month, the dates of occurrence for any measurements exceeding 5 NTU, and the dates the supplier reported the occurrences to the Agency.

8)         For the first 12 months of recordkeeping, the dates and cumulative number of events during which the turbidity exceeded 5 NTU.  After one year of recordkeeping for turbidity measurements, the dates and cumulative number of events during which the turbidity exceeded 5 NTU in the previous 12 months the supplier served water to the public.

9)         For the first 120 months of recordkeeping, the dates and cumulative number of events during which the turbidity exceeded 5 NTU.  After ten years of recordkeeping for turbidity measurements, the dates and cumulative number of events during which the turbidity exceeded 5 NTU in the previous 120 months the supplier served water to the public.

b)         The supplier must report the Agency disinfection information Section 611.532 specifies within ten days after the end of each month the supplier serves water to the public.  The information the supplier reports must include specific information:

1)         For each day, the lowest RDC measurement in mg/L in water entering the distribution system.

2)         The date and duration of each period during which the RDC in water entering the distribution system fell below 0.2 mg/L and the supplier notified the Agency of the occurrence.

3)         The daily RDCs (in mg/L) and disinfectant contact times (in minutes) the supplier used for calculating the CT values.

4)         If the supplier uses chlorine, the daily pH measurements of disinfected water following each point of chlorine disinfection.

5)         The daily water temperature measurements (in °C) following each point of disinfection.

6)         The daily CT_calc and A_i values for each disinfectant measurement or sequence and the sum of all A_i values (B) before or at the first customer.

7)         The daily determination whether disinfection achieves adequate Giardia cyst and virus inactivation, i.e., whether A_i is at least 1.0.  If the supplier uses a disinfectant other than chlorine, the supplier must use other indicator conditions the Agency determines appropriate under Section 611.241(a)(1).

8)         Specific information on the supplier's distribution system samples the supplier took for total coliform monitoring under Sections 611.240 through 611.242:

A)        The number of times when the supplier measured the RDC;

B)        The number of times when the supplier did not measure the RDC but did measure HPC;

C)        The number of times the supplier measured but did not detect RDC and measured HPC;

D)        The number of times when the supplier measured but did not detect the RDC, and the HPC is greater than 500/ml;

E)        The number of times when the supplier did not measure the RDC, and the HPC is greater than 500/ml;

F)         For the current and previous month the supplier served water to the public, the value of "V" in the following formula:

where:

G)        Subsections (b)(8)(A) through (b)(8)(F) do not apply if the Agency determines, under Section 611.213, that a supplier has no means for having a sample analyzed for HPC by a certified laboratory under the requisite time and temperature conditions specified by Section 611.531(a) and that the supplier adequately provides disinfection in the distribution system.

9)         A supplier needs not report the data subsections (b)(1) and (b)(3) through (b)(6) require if all data subsections (b)(1) through (b)(8) require remain on file at the system, and the Agency issues a SEP making specific determinations:

A)        That the supplier submitted all the information subsections (b)(1) through (b)(8) require to the Agency for at least 12 months; and

B)        That the supplier needs not provide filtration treatment.

c)         By October 10 of each year, every supplier must provide a report to the Agency summarizing its compliance with all watershed control program requirements in Section 611.232(b).

d)         By October 10 of each year, every supplier must provide a report to the Agency on the on-site inspection the supplier conducted during that year under Section 611.232(c), unless the Agency conducted the on-site inspection.  If the Agency conducted the inspection, the Agency must provide a copy of its report to the supplier.

e)         Reporting Health Threats

1)         Upon discovering that a waterborne disease outbreak occurred that is potentially attributable to its water system, a supplier must report that occurrence to the Agency as soon as possible but no later than by the end of the next business day.

2)         If at any time the turbidity exceeds 5 NTU, the supplier must consult with the Agency as soon as practical, but no later than 24 hours after the supplier knows of the exceedance, under Section 611.903(b)(3).

3)         If at any time the RDC falls below 0.2 mg/L in the water entering the distribution system, the supplier must notify the Agency as soon as possible but no later than by the end of the next business day.  The supplier must also notify the Agency by the end of the next business day whether or not the supplier restored the RDC to at least 0.2 mg/L within four hours.

BOARD NOTE:  This Section derives from 40 CFR 141.75(a).

(Source:  Amended at 47 Ill. Reg. 16486, effective November 2, 2023)