Section 611.1007  Source Water Monitoring Requirements:  Grandfathering Previously Collected Data

a)         Initial Source Monitoring and Cryptosporidium Samples

1)         A supplier may comply with the initial source water monitoring requirements of Section 611.1001(a) by grandfathering sample results collected before the supplier is required to begin monitoring (i.e., previously collected data).  To be grandfathered, the sample results and analysis must meet the criteria in this Section and the Agency must approve the use of the data by a SEP.

2)         A filtered system supplier may grandfather Cryptosporidium samples to meet the requirements of Section 611.1001(a) when the supplier does not have corresponding E. coli and turbidity samples.  A supplier that grandfathers Cryptosporidium samples without E. coli and turbidity samples is not required to collect E. coli and turbidity samples when it completes the requirements for Cryptosporidium monitoring under Section 611.1001(a).

b)         E. coli Sample Analysis.  The analysis of E. coli samples must meet the analytical method and approved laboratory requirements of Sections 611.1004 and 611.1005.

c)         Cryptosporidium Sample Analysis.  The analysis of Cryptosporidium samples must meet the criteria in this subsection (c).

1)         Laboratories must analyze Cryptosporidium samples using one of the following filtration, immunomagnetic separation, and immunofluorescence assay analytical methods, incorporated by reference in Section 611.102, or alternative methods approved by the Agency under Section 611.480:

A)        USEPA 1623 (05);

B)        USEPA 1622 (05);

C)        USEPA 1623 (01);

D)        USEPA 1622 (01); or

E)        USEPA 1623 (99)

2)         For each Cryptosporidium sample, the laboratory analyzed at least 10 ℓ of sample or at least 2 mℓ of packed pellet or as much volume as could be filtered by two filters that USEPA approved for the methods listed in subsection (c)(1).

d)         Sampling Location.  The sampling location must meet the conditions in Section 611.1003.

e)         Sampling Frequency.  Cryptosporidium samples were collected no less frequently than each calendar month on a regular schedule, beginning no earlier than January 1999.  Sample collection intervals may vary for the conditions specified in Section 611.1002(b)(1) and (b)(2) if the supplier provides documentation of the condition when reporting monitoring results.

1)         The Agency may, by a SEP, approve grandfathering of previously collected data where there are time gaps in the sampling frequency if the supplier conducts additional monitoring that the Agency has specified by a SEP to ensure that the data used to comply with the initial source water monitoring requirements of Section 611.1001(a) are seasonally representative and unbiased.

2)         A supplier may grandfather previously collected data where the sampling frequency within each month varied.  If the Cryptosporidium sampling frequency varied, the supplier must follow the monthly averaging procedure in Section 611.1010(b)(5) or Section 611.1012(a)(3), as applicable, when calculating the bin classification for a filtered system supplier or the mean Cryptosporidium concentration for an unfiltered system supplier.

f)         Reporting Monitoring Results for Grandfathering.  A supplier that requests to grandfather previously collected monitoring results must report the following information by the applicable dates listed in this subsection.  A supplier must report this information to the Agency.

1)         A supplier must report that it intends to submit previously collected monitoring results for grandfathering.  This report must specify the number of previously collected results the supplier will submit, the dates of the first and last sample, and whether a supplier will conduct additional source water monitoring to meet the requirements of Section 611.1001(a).  The supplier must report this information no later than the applicable date set forth in Section 611.1002.

2)         A supplier must report previously collected monitoring results for grandfathering, along with the associated documentation listed in subsections (f)(2)(A) through (f)(2)(D), no later than two months after the applicable date listed in Section 611.1001(c).

A)        For each sample result, a supplier must report the applicable data elements in Section 611.1006.

B)        A supplier must certify that the reported monitoring results include all results that it generated during the time period beginning with the first reported result and ending with the final reported result.  This applies to samples that were collected from the sampling location specified for source water monitoring under this Subpart Z, which were not spiked, and which were analyzed using the laboratory's routine process for the analytical methods listed in this Section.

C)        The supplier must certify that the samples were representative of a plant's source waters and the source waters have not changed.  It must report a description of the sampling locations, which must address the position of the sampling location in relation to its water sources and treatment processes, including points of chemical addition and filter backwash recycle.

D)        For Cryptosporidium samples, the laboratory or laboratories that analyzed the samples must provide a letter certifying that the quality control criteria specified in the methods listed in subsection (c)(1) were met for each sample batch associated with the reported results.  Alternatively, the laboratory may provide bench sheets and sample examination report forms for each field, matrix spike, initial precision and recovery, ongoing precision and recovery, and method blank sample associated with the reported results.

g)         If the Agency determines that a previously collected data set submitted for grandfathering was generated during source water conditions that were not normal for the supplier, such as a drought, the Agency may, by a SEP, disapprove the data.  Alternatively, the Agency may, by a SEP, approve the previously collected data if the supplier reports additional source water monitoring data, as determined by the Agency, to ensure that the data set used under Section 611.1010 or Section 611.1012 represents average source water conditions for the supplier.

h)         If a supplier submits previously collected data that fully meet the number of samples required for initial source water monitoring under Section 611.1001(a), and some of the data are rejected due to not meeting the requirements of this Section, the supplier must conduct additional monitoring to replace rejected data on a schedule that the Agency has approved by a SEP.  A supplier is not required to begin this additional monitoring until two months after notification that data have been rejected and additional monitoring is necessary.

BOARD NOTE:  Derived from 40 CFR 141.707.

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