Current through Register Vol. 48, No. 38, September 20, 2024
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.
BOARD NOTE: Derived from
40 CFR
141.175.
