| (A) Circumstances warranting the exercise of such discretion
may include:
(i) the public water system has failed to provide any
of the required compliance information to the executive director as
described in §290.111(h)(2) of this title (relating to Surface
Water Treatment) and the failure results in the inability of the executive
director to determine compliance as described in §290.111(i)
of this title or the existence of a potential or actual health hazard,
as described in §290.38 of this title (relating to Definitions);
or
(ii) waterborne emergencies for situations that do
not meet the definition of waterborne disease outbreak as defined
in 40 Code of Federal Regulations §141.2, but that still have
the potential to have serious adverse health effects as a result of
short-term exposure. These can include, but are not limited to, outbreaks
not related to treatment deficiencies, as well as situations that
have the potential to cause outbreaks, such as failures or significant
interruption in water treatment processes, natural disasters that
disrupt the water supply or distribution system, chemical spills,
or unexpected loading of possible pathogens into the source water.
(B) The executive director will provide written notification
to the public water system in the event a public water system is required
to institute special precautions, protective measures, or issue boil
water notices to customers at the discretion of the executive director.
Upon written notification from the executive director, the public
water system shall implement special precautions, protective measures,
or issue boil water notices to customers within 24 hours or within
the time period specified by the executive director. The executive
director may specify, in writing, additional required actions to the
requirements described in paragraph (6) of this subsection for a public
water system to rescind the notice.
(C) The public water system shall provide any required
information to the executive director to document that the public
water system has met the rescind requirements for special precautions,
protective measures, and boil water notices required at the discretion
of the executive director under this paragraph.
(6) Once the boil water notice, special precaution,
or protective measure is no longer in effect, the public water system
shall notify customers that the notice has been rescinded. A public
water system shall not rescind a notice or notify customers that a
notice has been rescinded until the public water system has met all
the applicable requirements, as described in subparagraph (A) of this
paragraph.
(A) Required actions prior to rescinding a boil water
notice include:
(i) water distribution system pressures in excess of
20 psi are consistently being maintained throughout the distribution
system in accordance with the flowchart found in §290.47(e) of
this title (relating to Appendices);
(ii) a minimum of 0.2 mg/L free chlorine residual or
0.5 mg/L chloramine residual (measured as total chlorine) is present
and is consistently being maintained in each finished water storage
tank and throughout the distribution system as described in subsection
(d) of this section;
(iii) finished water entering the distribution system,
produced by a treatment plant that is treating surface water or groundwater
under the direct influence of surface water, has a turbidity level
that is consistently below 1.0 NTU and the affected areas of the distribution
system have been thoroughly flushed;
(iv) additional actions may be required by the executive
director, in writing, and these additional actions shall be completed
and documentation provided to the executive director for approval
prior to the public water system rescinding the notice, and
(v) water samples for microbiological analysis, marked
as "special" on the laboratory sample submission form, were collected
from representative locations throughout the distribution system or
in the affected area(s) of the distribution system after the public
water system has met all other applicable requirements of this paragraph
and the water samples collected for microbiological analysis are found
negative for coliform organisms. The water samples described in this
subparagraph shall be analyzed at laboratories in accordance with §290.119
of this title (relating to Analytical Procedures).
(B) A public water system shall notify customers that
the notice has been rescinded within 24 hours or no later than the
next business day, using language and format specified by the executive
director once the public water system has met the requirements of
this paragraph. The method of delivery of the rescind notice must
be in a manner similar to the original notice.
(C) The public water system shall provide a copy of
the rescind notice, a copy of the associated microbiological laboratory
analysis results, as required by subparagraph (A) of this paragraph,
and a signed Certificate of Delivery to the executive director within
ten days after the public water system has issued the rescind notice
to customers in accordance with §290.122(f) of this title.
(r) Minimum pressures. All public water systems shall
be operated to provide a minimum pressure of 35 psi throughout the
distribution system under normal operating conditions. The system
shall also be operated to maintain a minimum pressure of 20 psi during
emergencies such as firefighting. As soon as safe and practicable
following the occurrence of a natural disaster, a public water system
that is an affected utility, as defined in TWC §13.1394 or §13.1395,
shall maintain a minimum of 20 psi or a pressure approved by the executive
director, or 35 psi, respectively, throughout the distribution system
during an extended power outage.
(s) Testing equipment. Accurate testing equipment or
some other means of monitoring the effectiveness of any chemical treatment
or pathogen inactivation or removal processes must be used by the
system.
(1) Flow-measuring devices and rate-of-flow controllers
that are required by §290.42(b) and (d) of this title (relating
to Water Treatment) shall be calibrated at least once every 12 months.
Well meters required by §290.41(c)(3)(N) of this title shall
be calibrated at least once every three years.
(2) Laboratory equipment used for compliance testing
shall be properly calibrated.
(A) pH meters shall be properly calibrated.
(i) Benchtop pH meters shall be calibrated according
to manufacturer specifications at least once each day.
(ii) The calibration of benchtop pH meters shall be
checked with at least one buffer each time a series of samples is
run, and if necessary, recalibrated according to manufacturer specifications.
(iii) On-line pH meters shall be calibrated according
to manufacturer specifications at least once every 30 days.
(iv) The calibration of on-line pH meters shall be
checked at least once each week with a primary standard or by comparing
the results from the on-line unit with the results from a properly
calibrated benchtop unit. If necessary, the on-line unit shall be
recalibrated with primary standards.
(B) Turbidimeters shall be properly calibrated.
(i) Benchtop turbidimeters shall be calibrated with
primary standards at least once every 90 days. Each time the turbidimeter
is calibrated with primary standards, the secondary standards shall
be restandardized.
(ii) The calibration of benchtop turbidimeters shall
be checked with secondary standards each time a series of samples
is tested, and if necessary, recalibrated with primary standards.
(iii) On-line turbidimeters shall be calibrated with
primary standards at least once every 90 days.
(iv) The calibration of on-line turbidimeters shall
be checked at least once each week with a primary standard, a secondary
standard, or the manufacturer's proprietary calibration confirmation
device or by comparing the results from the on-line unit with the
results from a properly calibrated benchtop unit. If necessary, the
on-line unit shall be recalibrated with primary standards.
(C) Chemical disinfectant residual analyzers shall
be properly calibrated.
(i) The accuracy of manual disinfectant residual analyzers
shall be verified at least once every 90 days using chlorine solutions
of known concentrations.
(ii) The accuracy of continuous disinfectant residual
analyzers shall be checked at least once every seven days with a chlorine
solution of known concentration or by comparing the results from the
on-line analyzer with the result of approved benchtop method in accordance
with §290.119 of this title.
Cont'd... |
