Utah Administrative Code
Topic - Environmental Quality
Title R309 - Drinking Water
Rule R309-215 - Monitoring and Water Quality: Treatment Plant Monitoring Requirements
Section R309-215-14 - Disinfection Profiling and Benchmarking
Universal Citation: UT Admin Code R 309-215-14
Current through Bulletin 2024-18, September 15, 2024
A disinfection profile is a graphical representation of your system's level of Giardia lamblia or virus inactivation measured during the course of a year. Community or non-transient non-community water systems which use surface water or ground water under the direct influence of surface must develop a disinfection profile unless the Director determines that a system's profile is unnecessary. The Director may approve the use of a more representative data set for disinfection profiling than the data set required under R309-215-14.
(1) Determination of systems required to profile. A public water system subject to the requirements of this subpart shall determine its TTHM annual average using the procedure in paragraph (1)(a) of this section and its HAA5 annual average using the procedure in paragraph (1)(b) of this section. The annual average is the arithmetic average of the quarterly averages of four consecutive quarters of monitoring.
(a) The TTHM annual average shall
be the annual average during the same period as is used for the HAA5 annual
average.
(i) Those systems that collected
data under the provisions of 40 CFR 141.142 subpart M (Information Collection
Rule) shall use the results of the samples collected during the last four
quarters of required monitoring.
(ii) Those systems that use grandfathered
HAA5 occurrence data that meet the provisions of paragraph (1)(b)(ii) of this
section shall use TTHM data collected at the same time under the provisions of
R309-200-5(3)(c)(vii)
and
R309-210-9.
(iii) Those systems that use HAA5 occurrence
data that meet the provisions of paragraph (1)(b)(iii)(A) of this section shall
use TTHM data collected at the same time under the provisions of
R309-200-5(3)(c)(vii)
and
R309-210-9.
(b) The HAA5 annual average shall
be the annual average during the same period as is used for the TTHM annual
average.
(i) Those systems that collected
data under the provisions of 40 CFR 141.142 subpart M (Information Collection
Rule) shall use the results of the samples collected during the last four
quarters of required monitoring.
(ii) Those systems that have collected four
quarters of HAA5 occurrence data that meets the routine monitoring sample
number and location requirements for TTHM in
R309-200-5(3)(c)(vii)
and
R309-210-9 and handling and analytical method requirements of
R309-200-4(3)
may use those data to determine whether the requirements of this section
apply.
(iii) Those systems that
have not collected four quarters of HAA5 occurrence data that meets the
provisions of either paragraph (1)(b)(i) or (ii) of this section by March 16,
1999 shall either:
(A) Conduct monitoring for
HAA5 that meets the routine monitoring sample number and location requirements
for TTHM in
R309-200-5(3)(c)(vii)
and
R309-210-9 and handling and analytical method requirements of
R309-200-4(3)
to determine the HAA5 annual average and whether the requirements of paragraph
(2) of this section apply. This monitoring shall be completed so that the
applicability determination can be made no later than March 31, 2000,
or
(B) Comply with all other
provisions of this section as if the HAA5 monitoring had been conducted and the
results required compliance with paragraph (2) of this section.
(c) The system may
request that the Director approve a more representative annual data set than
the data set determined under paragraph (1)(a) or (b) of this section for the
purpose of determining applicability of the requirements of this
section.
(d) The Director may
require that a system use a more representative annual data set than the data
set determined under paragraph (1)(a) or (b) of this section for the purpose of
determining applicability of the requirements of this section.
(e) The system shall submit data to the
Director on the schedule in paragraphs (1)(e)(i) through (v) of this section.
(i) Those systems that collected TTHM and
HAA5 data under the provisions of subpart M (Information Collection Rule), as
required by paragraphs (1)(a)(i) and (1)(b)(i) of this section, shall submit
the results of the samples collected during the last 12 months of required
monitoring under 40 CFR section 141.142 (Information Collection Rule) not later
than December 31, 1999.
(ii) Those
systems that have collected four consecutive quarters of HAA5 occurrence data
that meets the routine monitoring sample number and location for TTHM in
R309-200-5(3)(c)(vii)
and
R309-210-9 and handling and analytical method requirements of
R309-200-4(3),
as allowed by paragraphs (1)(a)(ii) and (1)(b)(ii) of this section, shall
submit those data to the Director not later April 16, 1999. Until the Director
has approved the data, the system shall conduct monitoring for HAA5 using the
monitoring requirements specified under paragraph (1)(b)(iii) of this
section.
(iii) Those systems that
conduct monitoring for HAA5 using the monitoring requirements specified by
paragraphs (1)(a)(iii) and (1)(b)(iii)(A) of this section, shall submit TTHM
and HAA5 data not later than April 1, 2000.
(iv) Those systems that elect to comply with
all other provisions of this section as if the HAA5 monitoring had been
conducted and the results required compliance with this section, as allowed
under paragraphs (1)(b)(iii)(B) of this section, shall notify the Director in
writing of their election not later than December 31, 1999.
(v) If the system elects to request that the
Director approve a more representative annual data set than the data set
determined under paragraph (1)(b)(i) of this section, the system shall submit
this request in writing not later than December 31, 1999.
(f) Any system having either a TTHM annual
average greater than or equal to 0.064 mg/L or an HAA5 annual average greater
than or equal to 0.048 mg/L during the period identified in paragraphs (1)(a)
and (b) of this section shall comply with paragraph (2) of this
section.
(g) The Director may only
determine that a system's profile is unnecessary if a system's TTHM and HAA5
levels are below 0.064 mg/L and 0.048 mg/L, respectively. To determine these
levels, TTHM and HAA5 samples must be collected after January 1, 1998, during
the month with the warmest water temperature, and at the point of maximum
residence time in your distribution system. The Director may approve a more
representative TTHM and HAA5 data set to determine these levels.
(2) Disinfection profiling.
(a) Any system that is required by paragraph
(1) of this section shall develop a disinfection profile of its disinfection
practice for a period of up to three years. A disinfection profile consists of
the following 3 steps:
(i) The system must
collect data for several parameters from the plant over the course of 12
months. If your system serves between 500 and 9,999 persons you must begin to
collect data no later than July 1, 2003. If your system serves fewer than 500
persons you must begin to collect data no later than January 1, 2004. If your
system serves 10,000 persons or greater than the requirements of R309-215-14(2)
are only required if it meets the criteria in paragraph
R309-215-14(1)(f).
(ii) The system
must use this data to calculate weekly log inactivation as discussed in
paragraph (d) of this section.
(iii) The system must use these weekly log
inactivations to develop a disinfection profile.
(b) The system shall monitor daily for a
period of 12 consecutive calendar months to determine the total logs of
inactivation for each day of operation, based on the CT99.9 values in Tables
1.1-1.6, 2.1, and 3.1 of Section 141.74(b)(3) in the code of Federal
Regulations (also available from the Division), as appropriate, through the
entire treatment plant. This system shall begin this monitoring not later than
April 1, 2000. As a minimum, the system with a single point of disinfectant
application prior to entrance to the distribution system shall conduct the
monitoring in paragraphs (2)(b)(i) through (iv) of this section. A system with
more than one point of disinfectant application shall conduct the monitoring in
paragraphs (2)(b)(i) through (iv) of this section for each disinfection
segment. The system shall monitor the parameters necessary to determine the
total inactivation ratio, using analytical methods in
R309-200-4(3),
as follows:
(i) The temperature of the
disinfected water shall be measured once per day at each residual disinfectant
concentration sampling point during peak hourly flow.
(ii) If the system uses chlorine, the pH of
the disinfected water shall be measured once per day at each chlorine residual
disinfectant concentration sampling point during peak hourly flow.
(iii) The disinfectant contact time(s) ("T")
shall be determined for each day during peak hourly flow.
(iv) The residual disinfectant
concentration(s) ("C") of the water before or at the first customer and prior
to each additional point of disinfection shall be measured each day during peak
hourly flow.
(v) For systems
serving less than 10,000 persons, the above parameters shall be monitored once
per week on the same calendar day, over 12 consecutive months for the purposes
of disinfection profiling.
(c) In lieu of the monitoring conducted under
the provisions of paragraph (2)(b) of this section to develop the disinfection
profile, the system may elect to meet the requirements of paragraph (2)(c)(i)
of this section. In addition to the monitoring conducted under the provisions
of paragraph (2)(b) of this section to develop the disinfection profile, the
system may elect to meet the requirements of paragraph (2)(c)(ii) of this
section.
(i) A PWS that has three years of
existing operational data may submit those data, a profile generated using
those data, and a request that the Director approve use of those data in lieu
of monitoring under the provisions of paragraph (2)(b) of this section not
later than March 31, 2000. The Director shall determine whether these
operational data are substantially equivalent to data collected under the
provisions of paragraph (2)(b) of this section. These data shall also be
representative of Giardia lamblia inactivation through the entire treatment
plant and not just of certain treatment segments. Until the Director approves
this request, the system is required to conduct monitoring under the provisions
of paragraph (2)(b) of this section.
(ii) In addition to the disinfection profile
generated under paragraph (2)(b) of this section, a PWS that has existing
operational data may use those data to develop a disinfection profile for
additional years. Such systems may use these additional yearly disinfection
profiles to develop a benchmark under the provisions of paragraph (3) of this
section. The Director shall determine whether these operational data are
substantially equivalent to data collected under the provisions of paragraph
(2)(b) of this section. These data shall also be representative of inactivation
through the entire treatment plant and not just of certain treatment
segments.
(d) The system
shall calculate the total inactivation ratio as follows:
(i) If the system uses only one point of
disinfectant application, the system may determine the total inactivation ratio
for the disinfection segment based on either of the methods in paragraph
(2)(d)(i)(A) or (2)(d)(i)(B) of this section.
(A) Determine one inactivation ratio
(CTcalc/CT99.9) before or at the first customer during
peak hourly flow.
(B) Determine
successive CTcalc/CT99.9 values, representing sequential
inactivation ratios, between the point of disinfectant application and a point
before or at the first customer during peak hourly flow. Under this
alternative, the system shall calculate the total inactivation ratio by
determining (CTcalc/CT99.9) for each sequence and then
adding the (CTcalc/CT99.9) values together to determine
sum of (CTcalc/CT99.9).
(ii) If the system uses more than one point
of disinfectant application before the first customer, the system shall
determine the CT value of each disinfection segment immediately prior to the
next point of disinfectant application, or for the final segment, before or at
the first customer, during peak hourly flow. The
(CTcalc/CT99.9) value of each segment and sum of
(CTcalc/CT99.9) shall be calculated using the method in
paragraph (b)(4)(i) of this section.
(iii) The system shall determine the total
logs of inactivation by multiplying the value calculated in paragraph (2)(d)(i)
or (ii) of this section by 3.0.
(e) A system that uses either chloramines and
chlorine dioxide or ozone for primary disinfection shall also calculate the
logs of inactivation for viruses using a method approved by the
Director.
(f) The system shall
retain disinfection profile data in graphic form, as a spreadsheet, or in some
other format acceptable to the Director for review as part of sanitary surveys
conducted by the Director.
(3) Disinfection Benchmarking
(a) Any system required to develop a
disinfection profile under the provisions of paragraphs (1) and (2) of this
section and that decides to make a significant change to its disinfection
practice shall consult with the Director prior to making such change.
Significant changes to disinfection practice are:
(i) Changes to the point of
disinfection;
(ii) Changes to the
disinfectant(s) used in the treatment plant;
(iii) Changes to the disinfection process;
and
(iv) Any other modification
identified by the Director.
(b) Any system that is modifying its
disinfection practice shall calculate its disinfection benchmark using the
procedure specified in paragraphs (3)(b)(i) through (ii) of this section.
(i) For each year of profiling data collected
and calculated under paragraph (2) of this section, the system shall determine
the lowest average monthly Giardia lamblia inactivation in each year of
profiling data. The system shall determine the average Giardia lamblia
inactivation for each calendar month for each year of profiling data by
dividing the sum of daily Giardia lamblia of inactivation by the number of
values calculated for that month.
(ii) The disinfection benchmark is the lowest
monthly average value (for systems with one year of profiling data) or average
of lowest monthly average values (for systems with more than one year of
profiling data) of the monthly logs of Giardia lamblia inactivation in each
year of profiling data.
(c) A system that uses either chloramines,
ozone or chlorine dioxide for primary disinfection must calculate the
disinfection benchmark from the data the system collected for viruses to
develop the disinfection profile in addition to the Giardia lamblia
disinfection benchmark calculated under paragraph (b)(i) above. This viral
benchmark must be calculated in the same manner used to calculate the Giardia
lamblia disinfection benchmark in paragraph (b)(i).
(d) The system shall submit information in
paragraphs (3)(d)(i) through (iv) of this section to the Director as part of
its consultation process.
(i) A description
of the proposed change;
(ii) The
disinfection profile for Giardia lamblia (and, if necessary, viruses) under
paragraph (2) of this section and benchmark as required by paragraph (3)(b) of
this section; and
(iii) An analysis
of how the proposed change will affect the current levels of
disinfection.
(iv) Any additional
information requested by the Director.
Disclaimer: These regulations may not be the most recent version. Utah may have more current or accurate information. We make no warranties or guarantees about the accuracy, completeness, or adequacy of the information contained on this site or the information linked to on the state site. Please check official sources.
This site is protected by reCAPTCHA and the Google
Privacy Policy and
Terms of Service apply.
