Current through Register Vol. 48, No. 38, September 20, 2024
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.
