Current through Register Vol. 48, No. 38, September 20, 2024
a)
General
1) This Section applies to non-CWS
suppliers that use only groundwater (except groundwater under the direct
influence of surface water, as defined in Section
611.102
) and which serve 1,000 or fewer people.
2) Following any total coliform-positive
sample taken under this Section, a supplier must comply with the repeat
monitoring requirements and E. coli analytical requirements in Section
611.1058.
3) Once all monitoring required by this
Section and Section
611.1058
for a calendar month has been completed, a supplier must determine whether any
coliform treatment technique triggers specified in Section
611.1059
have been exceeded. If any trigger has been exceeded, the supplier must
complete assessments as required by Section 611.1059.
4) For the purpose of determining eligibility
for remaining on or qualifying for quarterly monitoring under the provisions of
subsections (f)(4) and (g)(2), respectively, for transient non-CWS suppliers,
the Agency may elect to not count monitoring violations under Section
611.1060(c)(1)
if the missed sample is collected no later than the end of the monitoring
period following the monitoring period in which the sample was missed. The
supplier must collect the make-up sample in a different week than the routine
sample for that monitoring period and should collect the sample as soon as
possible during the monitoring period. The Agency may not use this provision
under subsection (h). This authority does not affect the provisions of Sections
611.1060(c)(1)
and
611.1061(a)(4).
b) Monitoring Frequency for Total
Coliforms. A supplier must monitor each calendar quarter that the supplier
provides water to the public, except for a seasonal system supplier or as
provided under subsections (c) through (h) and (j). A seasonal system supplier
must meet the monitoring requirements of subsection (i).
c) Transition to This Subpart AA. The Agency
must perform a special monitoring evaluation during each sanitary survey to
review the status of the supplier's system, including the distribution system,
to determine whether the supplier is on an appropriate monitoring schedule.
After the Agency has performed the special monitoring evaluation during each
sanitary survey, the Agency may modify the supplier's monitoring schedule, as
the Agency determines is necessary, or the Agency may allow the supplier to
stay on its existing monitoring schedule, consistent with the provisions of
this Section. The Agency may not allow a supplier to begin less frequent
monitoring under the special monitoring evaluation unless the supplier has
already met the applicable criteria for less frequent monitoring in this
Section. For a seasonal system supplier on quarterly or annual monitoring, this
evaluation must include review of the approved sample siting plan, which must
designate the time periods for monitoring based on site-specific considerations
(e.g., during periods of highest demand or highest vulnerability to
contamination). The seasonal system supplier must collect compliance samples
during these time periods.
d)
Annual Site Visits. A supplier on annual monitoring, including a seasonal
system supplier, must have an initial and recurring annual site visit by the
Agency that is equivalent to a Level 2 assessment or an annual voluntary Level
2 assessment that meets the criteria in Section
611.1059(b)
to remain on annual monitoring. The periodic required sanitary survey may be
used to meet the requirement for an annual site visit for the year in which the
sanitary survey was completed.
e)
Criteria for Annual Monitoring. The Agency may, by a SEP, reduce the monitoring
frequency for a well-operated GWS supplier from quarterly routine monitoring to
no less than annual monitoring, if the supplier demonstrates that it meets the
criteria for reduced monitoring in subsections (e)(1) through (e)(3), except
for a supplier that has been on increased monitoring under the provisions of
subsection (f). A supplier on increased monitoring under subsection (f) must
meet the provisions of subsection (g) to go to quarterly monitoring and must
meet the provisions of subsection (h) to go to annual monitoring.
1) The supplier's system has a clean
compliance history for a minimum of 12 months;
2) The most recent sanitary survey shows that
the supplier's system is free of sanitary defects or has corrected all
identified sanitary defects, has a protected water source, and meets
Agency-approved construction standards; and
3) The Agency has conducted an annual site
visit within the last 12 months, and the supplier has corrected all identified
sanitary defects. The supplier may substitute a Level 2 assessment that meets
the criteria in Section
611.1059(b)
for the Agency annual site visit.
f) Increased Monitoring
Requirements for Suppliers on Quarterly or Annual Monitoring. A supplier on
quarterly or annual monitoring that experiences any of the events identified in
subsections (f)(1) through (f)(4) must begin monthly monitoring the month
following the event. A supplier on annual monitoring that experiences the event
identified in subsections (f)(5) must begin quarterly monitoring the quarter
following the event. The supplier must continue monthly or quarterly monitoring
until the requirements in subsection (g) for quarterly monitoring or subsection
(h) for annual monitoring are met. A supplier on monthly monitoring for reasons
other than those identified in subsections (f)(1) through (f)(4) is not
considered to be on increased monitoring for the purposes of subsections (g)
and (h).
1) The supplier's system triggers a
Level 2 assessment or two Level 1 assessments under the provisions of Section
611.1059
in a rolling 12-month period.
2)
The supplier's system has an E. coli MCL violation.
3) The supplier's system has a coliform
treatment technique violation.
4)
The supplier's system has two Subpart AA monitoring violations or one Subpart
AA monitoring violation and one Level 1 assessment under the provisions of
Section
611.1059
in a rolling 12-month period for a system on quarterly monitoring.
5) The supplier's system has one Subpart AA
monitoring violation for a system on annual monitoring.
g) Requirements for Returning to Quarterly
Monitoring. The Agency may, by a SEP, reduce the monitoring frequency for a
supplier on monthly monitoring triggered under subsection (f) to quarterly
monitoring if the supplier's system meets the criteria in subsections (g)(1)
and (g)(2).
1) Within the last 12 months, the
supplier must have a completed sanitary survey or a site visit of its system by
the Agency or a voluntary Level 2 assessment of its system by a party approved
by the Agency, the supplier's system must be free of sanitary defects, and the
supplier's system must have a protected water source; and
2) The supplier's system must have a clean
compliance history for a minimum of 12 months.
h) Requirements for a Supplier on Increased
Monitoring to Qualify for Annual Monitoring. The Agency may, by a SEP, reduce
the monitoring frequency for a supplier on increased monitoring under
subsection (f) if the supplier's system meets the criteria in subsection (g)
and the criteria in subsections (h)(1) and (h)(2).
1) An annual site visit by the Agency and
correction of all identified sanitary defects. The supplier may substitute a
voluntary Level 2 assessment by a party approved by the Agency for the Agency
annual site visit in any given year.
2) The supplier must have in place or adopt
one or more of the following additional enhancements to the water system
barriers to contamination:
A) Cross connection
control, as approved by the Agency.
B) An operator certified by an appropriate
Agency certification program or regular visits by a circuit rider certified by
an appropriate Agency certification program.
C) Continuous disinfection entering the
distribution system and a residual in the distribution system in accordance
with criteria specified by the Agency.
D) Demonstration of maintenance of at least a
four-log removal or inactivation of viruses as provided for under Section
141.403(b)(3).
E) Other equivalent
enhancements to water system barriers as approved by the State.
i) Seasonal Systems
1) All seasonal system suppliers must
demonstrate completion of an Agency-approved start-up procedure, which may
include a requirement for startup sampling prior to serving water to the
public.
2) A seasonal system
supplier must monitor every month that it is in operation unless it meets the
criteria in subsections (i)(2)(i) through (iii) to be eligible for monitoring
less frequently than monthly, except as provided under subsection (c).
A) Seasonal a system supplier monitoring less
frequently than monthly must have an approved sample siting plan that
designates the time period for monitoring based on site-specific considerations
(e.g., during periods of highest demand or highest vulnerability to
contamination). A seasonal system supplier must collect compliance samples
during this time period.
B) To be
eligible for quarterly monitoring, the supplier must meet the criteria in
subsection (g).
C) To be eligible
for annual monitoring, the supplier must meet the criteria under subsection
(h).
3) The Agency may,
by a SEP, exempt any seasonal system supplier from some or all of the
requirements for seasonal system suppliers if the entire distribution system
remains pressurized during the entire period that the supplier's system is not
operating, except that a supplier that monitors less frequently than monthly
must still monitor during the vulnerable period designated by the Agency.
j) Additional Routine
Monitoring the Month Following a Total Coliform-Positive Sample. A supplier
that collects samples on a quarterly or annual frequency must conduct
additional routine monitoring the month following one or more total
coliform-positive samples (with or without a Level 1 treatment technique
trigger). The supplier must collect at least three routine samples during the
next month, except that the Agency may, by a SEP, waive this requirement if the
conditions of subsection (j)(1), (j)(2), or (j)(3) are met. The supplier may
either collect samples at regular time intervals throughout the month or may
collect all required routine samples on a single day if samples are taken from
different sites. The supplier must use the results of additional routine
samples in coliform treatment technique trigger calculations under Section
611.1059(a).
1) The Agency may, by a SEP, waive the
requirement to collect three routine samples the next month in which the
supplier provides water to the public if the Agency, or an agent approved by
the Agency, performs a site visit before the end of the next month in which the
supplier's system provides water to the public. Although a sanitary survey need
not be performed, the site visit must be sufficiently detailed to allow the
Agency to determine whether additional monitoring or any corrective action is
needed. The Agency cannot approve an employee of the supplier to perform this
site visit, even if the employee is an agent approved by the Agency to perform
sanitary surveys.
2) The Agency
may, by a SEP, waive the requirement to collect three routine samples the next
month in which the supplier provides water to the public if the Agency has
determined why the sample was total coliform-positive and has established that
the supplier has corrected the problem or will correct the problem before the
end of the next month in which the supplier's system serves water to the
public. In this case, the Agency must document this decision to waive the
following month's additional monitoring requirement in writing, have it
approved and signed by the supervisor of the Agency official who recommends
such a decision, and make this document available to USEPA and public. The
written documentation must describe the specific cause of the total
coliform-positive sample and what action the supplier has taken or will take to
correct this problem.
3) The Agency
may not waive the requirement to collect three additional routine samples the
next month in which the supplier's system provides water to the public solely
on the grounds that all repeat samples are total coliform-negative. If the
Agency determines that the supplier has corrected the contamination problem
before the supplier takes the set of repeat samples required in Section
611.1058, and all repeat samples were total coliform-negative, the Agency may,
by a SEP, waive the requirement for additional routine monitoring the next
month.
BOARD NOTE: Derived from
40
CFR 141.854.
