require the system to conduct additional water quality parameter
monitoring in accordance with Sec.  141.87(b) to assist the State in
reviewing the system's recommendation for a designation of optimal
corrosion control treatment. Large systems must complete the study in
paragraph (c)(2) of this section.
    (6) Based upon the results of lead and copper tap sampling and
water quality parameter monitoring, any small system with corrosion
control treatment exceeding an action level shall recommend designation
of one or more of the corrosion control treatments listed in paragraph
(c)(2) of this section as the optimal corrosion control for that system
or State approval of one of the small system options listed in
paragraph Sec.  141.93. The State may require the system to conduct
additional water quality parameter monitoring in accordance with Sec.
141.87(b) to assist the State in reviewing the system's recommendation.
    (7) Based upon the results of lead and copper tap sampling and
water quality parameter monitoring, any small system with corrosion
control treatment exceeding the lead trigger level shall recommend
designation of one or more of the corrosion control treatments listed
in paragraph (c)(2) of this section as the optimal corrosion control
treatment for that system or State approval of one of the small system
options listed in paragraph Sec.  141.93. This corrosion control
treatment or small system option shall be implemented if the lead or
copper action level is subsequently exceeded. The State may require the
system to conduct additional water quality parameter monitoring in
accordance with Sec.  141.87(b) to assist the State in reviewing the
system's recommendation.
    (b) State decision to require studies to identify initial optimal
corrosion control treatment (applicable to small and medium-size
systems) and re-optimized corrosion control treatment. (1) The State
may require any small or medium-size system without corrosion control
that exceeds either the lead or copper action level to perform
corrosion control treatment studies under paragraph (c)(1) of this
section to identify optimal corrosion control treatment for the system.
    (2) The State may require any small or medium-size system without
corrosion control that exceeds the lead trigger level to perform
corrosion control treatment studies under paragraph (c)(1) of this
section to identify optimal corrosion control treatment for the system.
This corrosion control treatment shall be installed if the lead or
copper action level is subsequently exceeded.
    (3) The State may require any small or medium-size water systems
with corrosion control treatment exceeding either the lead trigger
level or copper action level to perform corrosion control treatment
studies under paragraph (c)(3) of this section to identify re-optimized
optimal corrosion control treatment for the system (i.e. optimal
corrosion control treatment after a re-optimization evaluation).
    (c) Performance of corrosion control studies. (1) Water systems
without corrosion control that are conducting corrosion control studies
shall complete the following:
    (i) Any water system without corrosion control treatment shall
evaluate the effectiveness of each of the following treatments, and if
appropriate, combinations of the following treatments to identify the
optimal corrosion control treatment for the system:
    (A) Alkalinity and pH adjustment;
    (B) The addition of an orthophosphate- or silicate-based corrosion
inhibitor at a concentration sufficient to maintain an effective
residual concentration in all test tap samples;
    (C) The addition of an orthophosphate-based corrosion inhibitor at
a concentration sufficient to maintain a 1 mg/L orthophosphate residual
concentration in all tap test samples, and;
    (D) The addition of an orthophosphate-based corrosion inhibitor at
a concentration sufficient to maintain a 3 mg/L orthophosphate residual
concentration in all tap test samples.
    (ii) The water system shall evaluate each of the corrosion control
treatments using either pipe rig/loop tests, partial-system tests, or
analyses based on documented analogous treatments with other systems of
similar size, water chemistry, and distribution system configurations.
Metal coupon tests can be used as a screen to reduce the number of
options that are evaluated using pipe rig/loops to the current
conditions and two options.
    (iii) The water system shall measure the following water quality
parameters in any tests conducted under this paragraph before and after
evaluating the corrosion control treatments previously listed in this
section:
    (A) Lead;
    (B) Copper;
    (C) pH;
    (D) Alkalinity;
    (E) Orthophosphate (when an orthophosphate-based inhibitor is
used), and;
    (F) Silicate (when a silicate-based inhibitor is used).
    (iv) The water system shall identify all chemical or physical
constraints that limit or prohibit the use of a particular corrosion
control treatment and

document such constraints with one of the following:
    (A) Data and documentation showing that a particular corrosion
control treatment has adversely affected other water treatment
processes when used by another water system with comparable water
quality characteristics. Systems using coupon studies to screen and/or
pipe loop/rig studies to evaluate treatment options shall not exclude
treatment strategies from the studies based on the constraints
identified in this section.
    (B) Data and documentation demonstrating that the water system has
previously attempted to evaluate a particular corrosion control
treatment and has found that the treatment is ineffective or adversely
affects other water quality treatment processes. Systems using coupon
studies to screen and/or pipe loop/rig studies to evaluate treatment
options shall not exclude treatment strategies from the studies based
on the constraints identified in this section unless the treatment was
found to be ineffective in a previous pipe loop/rig study.
    (v) The water system shall evaluate the effect of the chemicals
used for corrosion control treatment on other water quality treatment
processes. Systems using coupon studies to screen and/or pipe loop/rig
studies to evaluate treatment options shall not exclude treatment
strategies from the studies based on the effects identified in this
section.
    (vi) On the basis of an analysis of the data generated during each
evaluation, the water system shall recommend to the State in writing
the treatment option that the corrosion control studies indicate
constitutes optimal corrosion control treatment for that system. The
water system shall provide a rationale for its recommendation along
with all supporting documentation specified in paragraphs (c)(2)(i)
through (v) of this section.
    (2) Systems with a pH and alkalinity corrosion control treatment
process conducting re-optimization corrosion control studies shall
complete the following:
    (i) Any system with a pH and alkalinity corrosion control treatment
process shall evaluate the effectiveness of each of the following
treatments, and if appropriate, combinations of the following
treatments to identify the optimal corrosion control treatment for the
system:
    (A) Additional alkalinity and/or pH adjustment;
    (B) The addition of an orthophosphate- or silicate-based corrosion
inhibitor at a concentration sufficient to maintain an effective
residual concentration in all test tap samples;
    (C) The addition of an orthophosphate-based corrosion inhibitor at
a concentration sufficient to maintain a 1 mg/L orthophosphate residual
concentration in all tap test samples, and;
    (D) The addition of an orthophosphate-based corrosion inhibitor at
a concentration sufficient to maintain a 3 mg/L orthophosphate residual
concentration in all tap test samples.
    (ii) The system shall evaluate each of the corrosion control
treatments using either pipe rig/loop tests, partial-system tests, or
analyses based on documented analogous treatments with other systems of
similar size, water chemistry, and distribution system configurations.
Coupon tests can be used as a screen to reduce the number of options
that are evaluated using pipe rig/loops to the current conditions and
two options.
    (iii) The water system shall measure the following water quality
parameters in any tests conducted under this paragraph before and after
evaluating the corrosion control treatments listed above:
    (A) Lead;
    (B) Copper;
    (C) pH;
    (D) Alkalinity;
    (E) Orthophosphate (when an orthophosphate-based inhibitor is
used), and;
    (F) Silicate (when a silicate-based inhibitor is used).
    (iv) The water system shall identify all chemical or physical
constraints that limit or prohibit the use of a particular corrosion
control treatment and document such constraints with one of the
following:
    (A) Data and documentation showing that a particular corrosion
control treatment has adversely affected other water treatment
processes when used by another water system with comparable water
quality characteristics. Systems using coupon studies to screen and/or
pipe loop/rig studies to evaluate treatment options shall not exclude
treatment strategies from the studies based on the constraints
identified in this section.
    (B) Data and documentation demonstrating that the water system has
previously attempted to evaluate a particular corrosion control
treatment and has found that the treatment is ineffective or adversely
affects other water quality treatment processes. Systems using coupon
studies to screen and/or pipe loop/rig studies to evaluate treatment
options shall not exclude treatment strategies from the studies based
on the constraints identified in this section unless the treatment was
found to be ineffective in a previous pipe loop/rig study.
    (v) The water system shall evaluate the effect of the chemicals
used for corrosion control treatment on other water quality treatment
processes. Systems using coupon studies to screen and/or pipe loop/rig
studies to evaluate treatment options shall not exclude treatment
strategies from the studies based on the effects identified in this
section.
    (vi) On the basis of an analysis of the data generated during each
evaluation, the water system shall recommend to the State in writing
the treatment option that the corrosion control studies indicate
constitutes optimal corrosion control treatment for that system. The
water system shall provide a rationale for its recommendation along
with all supporting documentation specified in paragraph (c)(1)(i)
through (v) of this section.
    (3) Systems with an inhibitor corrosion control treatment process
conducting re-optimization corrosion control studies shall complete the
following:
    (i) Any system with an inhibitor corrosion control treatment
process shall evaluate the effectiveness of each of the following
treatments, and if appropriate, combinations of the following
treatments to identify the optimal corrosion control treatment for the
system:
    (A) Alkalinity and/or pH adjustment;
    (B) The addition of an orthophosphate-based corrosion inhibitor at
a concentration sufficient to maintain a 1 mg/L orthophosphate residual
concentration in all tap test samples unless the current inhibitor
process already meets this residual, and;
    (C) The addition of an orthophosphate-based corrosion inhibitor at
a concentration sufficient to maintain a 3 mg/L orthophosphate residual
concentration in all tap test samples unless the current inhibitor
process already meets this residual.
    (ii) The system shall evaluate each of the corrosion control
treatments using either pipe rig/loop tests, partial-system tests, or
analyses based on documented analogous treatments with other systems of
similar size, water chemistry, and distribution system configurations.
Coupon tests can be used as a screen to reduce the number of options
that are evaluated using pipe rig/loops to the current conditions and
two options.
    (iii) The water system shall measure the following water quality
parameters in any tests conducted under this

paragraph before and after evaluating the corrosion control treatments
listed above:
    (A) Lead;
    (B) Copper;
    (C) pH;
    (D) Alkalinity;
    (E) Orthophosphate (when an orthophosphate-based inhibitor is
used), and;
    (F) Silicate (when a silicate-based inhibitor is used).
    (iv) The water system shall identify all chemical or physical
constraints that limit or prohibit the use of a particular corrosion
control treatment and document such constraints with one of the
following:
    (A) Data and documentation showing that a particular corrosion
control treatment has adversely affected other water treatment
processes when used by another water system with comparable water
quality characteristics. Systems using coupon studies to screen and/or
pipe loop/rig studies to evaluate treatment options shall not exclude
treatment strategies from the studies based on the constraints
identified in this section.
    (B) Data and documentation demonstrating that the water system has
previously attempted to evaluate a particular corrosion control
treatment and has found that the treatment is ineffective or adversely
affects other water quality treatment processes. Systems using coupon
studies to screen and/or pipe loop/rig studies to evaluate treatment
options shall not exclude treatment strategies from the studies based
on the constraints identified in this section unless the treatment was
found to be ineffective in a previous pipe loop/rig study.
    (v) The water system shall evaluate the effect of the chemicals
used for corrosion control treatment on other water quality treatment
processes. Systems using coupon studies to screen and/or pipe loop/rig
studies to evaluate treatment options shall not exclude treatment
strategies from the studies based on the effects identified in this
section.
    (vi) On the basis of an analysis of the data generated during each
evaluation, the water system shall recommend to the State in writing
the treatment option that the corrosion control studies indicate
constitutes optimal corrosion control treatment for that system. The
water system shall provide a rationale for its recommendation along
with all supporting documentation specified in paragraph (c)(3)(i)
through (v) of this section.
    (d) State designation of optimal corrosion control treatment and
re-optimized corrosion control treatment. (1) Designation of Initial
OCCT for medium systems. (i) Based upon considerations of available
information including, where applicable, studies conducted under
paragraph (c)(1) of this section and a system's recommended corrosion
control treatment option, the State shall either approve the corrosion
control treatment option recommended by the medium-size water system or
designate alternative corrosion control treatment(s) from among those
listed in paragraph (c)(1)(i) of this section. When designating optimal
corrosion control treatment, the State shall consider the effects that
additional corrosion control treatment will have on water quality
parameters and on other water quality treatment processes.
    (ii) The State shall notify the medium-size water system of its
decision on optimal corrosion control treatment in writing and explain
the basis for this determination. If the State requests additional
information to aid its review, the water system shall provide the
information.
    (2) Small systems. (i) Based upon considerations of available
information including, where applicable, studies conducted under
paragraph (c)(1) of this section and a system's recommended treatment
alternative, the State shall either approve the corrosion control
treatment option recommended by the small water system or designate
alternative corrosion control treatment(s) from among those listed in
paragraph (c)(1)(i) of this section or a small water system compliance
flexibility under Sec.  141.93. When designating optimal corrosion
control treatment, the State shall consider the effects that additional
corrosion control treatment will have on water quality parameters and
on other water quality treatment processes.
    (ii) The State shall notify the small water system of its decision
on either optimal corrosion control treatment or a small water system
compliance flexibility in writing and explain the basis for this
determination. If the State requests additional information to aid its
review, the water system shall provide the information.
    (3) Designation of Re-optimized OCCT for large and medium systems.
(i) Based upon considerations of available information including, where
applicable, studies conducted under paragraph (c)(2) or (c)(3) of this
section and a system's recommended treatment alternative, the State
shall either approve the corrosion control treatment modification
option recommended by the water system or designate alternative
corrosion control treatment(s) from among those listed in paragraph
(c)(2)(i) or (c)(3)(i) of this section. When designating re-optimized
corrosion control treatment, the State shall consider the effects that
additional corrosion control treatment will have on water quality
parameters and on other water quality treatment processes.
    (ii) The State shall notify the water system of its decision on re-
optimized corrosion control treatment in writing and explain the basis
for this determination. If the State requests additional information to
aid its review, the water system shall provide the information.
    (4) Designation of Re-optimization of OCCT or small water system
compliance flexibility. (i) Based upon considerations of available
information including, where applicable, studies conducted under
paragraph (c)(2) or (c)(3) of this section and a system's recommended
treatment alternative, the State shall either approve the corrosion
control treatment modification recommended by the small water system or
designate alternative corrosion control treatment(s) from among those
listed in paragraph (c)(2)(i) or (c)(3)(i) of this section or an
applicable small water system compliance flexibility under Sec.
141.93. When designating re-optimized corrosion control treatment, the
State shall consider the effects that additional corrosion control
treatment will have on water quality parameters and on other water
quality treatment processes.
    (ii) The State shall notify the water system of its decision on re-
optimized corrosion control treatment in writing and explain the basis
for this determination. If the State requests additional information to
aid its review, the water system shall provide the information.
    (e) Installation of optimal corrosion control treatment and re-
optimization of corrosion control treatment. (1) Each medium-size water
system shall properly install and operate throughout its distribution
system the optimal corrosion control treatment designated by the State
under paragraph (d)(1) of this section.
    (2) Each small water system shall properly install and operate
throughout its distribution system the optimal corrosion control
treatment or implement the small water system compliance flexibility as
designated by the State under paragraph (d)(2) of this section.
    (3) Each medium-size water system shall properly modify and operate
throughout its distribution system the re-optimized corrosion control

treatment designated by the State under paragraph (d)(3) of this
section.
    (4) Each small water system shall properly modify and operate
throughout its distribution system the re-optimized corrosion control
treatment or implement the small water system compliance flexibility
designated by the State under paragraph (d)(2) of this section.
    (f) State review of treatment and specification of optimal water
quality control parameters for optimal corrosion control treatment and
re-optimized corrosion control treatment. (1) The State shall evaluate
the results of all lead and copper tap sampling and water quality
parameter sampling submitted by the water system and determine whether
the water system has properly installed and operated the optimal
corrosion control treatment designated by the State in paragraph (d)(1)
or (d)(2) of this section, respectively. Upon reviewing the results of
tap water and water quality parameter monitoring by the water system,
both before and after the water system installs optimal corrosion
control treatment, the State shall designate:
    (i) A minimum value or a range of values for pH measured at each
entry point to the distribution system.
    (ii) A minimum pH value measured in all tap samples. Such a value
shall be equal to or greater than 7.0, unless the State determines that
meeting a pH level of 7.0 is not technologically feasible or is not
necessary for the system to optimize corrosion control.
    (iii) If a corrosion inhibitor is used, a minimum concentration or
a range of concentrations for orthophosphate or silicate measured at
each entry point to the distribution system.
    (iv) If a corrosion inhibitor is used, a minimum orthophosphate or
silicate concentration measured in all tap samples that the State
determines is necessary to form a passivating film on the interior
walls of the pipes of the distribution system. When orthophosphate is
used, such a concentration shall be equal to or greater than 0.5 mg/L
as orthophosphate, unless the State determines that meeting an
orthophosphate residual of 0.5 mg/L is not technologically feasible or
is not necessary for the system to optimize corrosion control.
    (v) If alkalinity is adjusted as part of optimal corrosion control
treatment, a minimum concentration or a range of concentrations for
alkalinity, measured at each entry point to the distribution system and
in all tap samples.
    (vi) The values for the applicable water quality control
parameters, previously listed in this section, shall be those that the
State determines to reflect optimal corrosion control treatment for the
water system. The State may designate values for additional water
quality control parameters determined by the State to reflect optimal
corrosion control for the water system. The State shall notify the
system in writing of these determinations and explain the basis for its
decisions.
    (2) The State shall evaluate the results of all lead and copper tap
sampling and water quality parameter monitoring submitted by the water
system and determine whether the water system has properly installed
and operated the re-optimized corrosion control treatment designated by
the State in paragraph (d)(3) or (d)(4) of this section, respectively.
Upon reviewing the results of tap sampling and water quality parameter
monitoring by the water system, both before and after the water system
installs re-optimized corrosion control treatment, the State shall
designate:
    (i) A minimum value or a range of values for pH measured at each
entry point to the distribution system.
    (ii) A minimum pH value measured in all tap samples. Such a value
shall be equal to or greater than 7.0, unless the State determines that
meeting a pH level of 7.0 is not technologically feasible or is not
necessary for the system to optimize corrosion control.
    (iii) If a corrosion inhibitor is used, a minimum concentration or
a range of concentrations for orthophosphate or silicate measured at
each entry point to the distribution system.
    (iv) If a corrosion inhibitor is used, a minimum orthophosphate or
silicate concentration measured in all tap samples that the State
determines is necessary to form a passivating film on the interior
walls of the pipes of the distribution system. When orthophosphate is
used, such a concentration shall be equal to or greater than 1.0 mg/L
as orthophosphate, unless the State determines that meeting an
orthophosphate residual of 1.0 mg/L is not technologically feasible or
is not necessary for the system to optimize corrosion control.
    (v) If alkalinity is adjusted as part of optimal corrosion control
treatment, a minimum concentration or a range of concentrations for
alkalinity, measured at each entry point to the distribution system and
in all tap samples.
    (vi) The values for the applicable water quality control
parameters, previously listed in this section, shall be those that the
State determines to reflect optimal corrosion control treatment for the
water system. The State may designate values for additional water
quality control parameters determined by the State to reflect optimal
corrosion control for the water system. The State shall notify the
system in writing of these determinations and explain the basis for its
decisions.
    (g) Continued operation and monitoring for optimal corrosion
control treatment and re-optimized corrosion control treatment. (1) All
systems optimizing corrosion control shall continue to operate and
maintain optimal corrosion control treatment, including maintaining
water quality parameters at or above minimum values or within ranges
designated by the State under paragraph (f)(1) of this section, in
accordance with this paragraph for all samples collected under Sec.
141.87(d) through (f). The requirements of this paragraph (g) apply to
all systems, including consecutive systems that distribute water that
has been treated to control corrosion by another system. Any water
system with optimal corrosion control treatment or re-optimized
corrosion control treatment that is not required to monitor water
quality parameters under Sec.  141.87 shall continue to operate and
maintain such treatment. Compliance with the requirements of this
paragraph shall be determined every six months, as specified under
Sec.  141.87(d). A water system is out of compliance with the
requirements of this paragraph for a six-month period if it has
excursions for any State-specified parameter on more than nine days
during the period. An excursion occurs whenever the daily value for one
or more of the water quality parameters measured at a sampling location
is below the minimum value or outside the range designated by the
State. Daily values are calculated as follows. States have discretion
to delete results of obvious sampling errors from this calculation.
    (i) On days when more than one measurement for the water quality
parameter is collected at the sampling location, the daily value shall
be the average of all results collected during the day regardless of
whether they are collected through continuous monitoring, grab
sampling, or a combination of both. If the EPA has approved an
alternative formula under Sec.  142.16(d)(1)(ii) of this chapter in the
State's application for a program revision submitted pursuant to Sec.
142.12 of this chapter, the State's formula shall be used to aggregate
multiple measurements taken at a sampling point for the water quality
parameters in lieu of the formula in this paragraph.

    (ii) On days when only one measurement for the water quality
parameter is collected at the sampling location, the daily value shall
be the result of that measurement.
    (iii) On days when no measurement is collected for the water
quality parameter at the sampling location, the daily value shall be
the daily value calculated on the most recent day on which the water
quality parameter was measured at the sampling location.
    (2) All systems re-optimizing corrosion control shall continue to
operate and maintain re-optimized corrosion control treatment,
including maintaining water quality parameters at or above minimum
values or within ranges designated by the State under paragraph (f)(2)
of this section, in accordance with this paragraph for all samples
collected under Sec.  141.87(d) through (f). Compliance with the
requirements of this paragraph shall be determined every six months, as
specified under Sec.  141.87(d). A water system is out of compliance
with the requirements of this paragraph for a six-month period if it
has excursions for any State-specified parameter on more than nine days
during the period. An excursion occurs whenever the daily value for one
or more of the water quality parameters measured at a sampling location
is below the minimum value or outside the range designated by the
State. Daily values are calculated as follows. States have discretion
to delete results of obvious sampling errors from this calculation.
    (i) On days when more than one measurement for the water quality
parameter is collected at the sampling location, the daily value shall
be the average of all results collected during the day regardless of
whether they are collected through continuous monitoring, grab
sampling, or a combination of both. If the EPA has approved an
alternative formula under Sec.  142.16(d)(1)(ii) of this chapter in the
State's application for a program revision submitted pursuant to Sec.
142.12 of this chapter, the State's formula shall be used to aggregate
multiple measurements taken at a sampling point for the water quality
parameters in lieu of this formula in this paragraph.
    (ii) On days when only one measurement for the water quality
parameter is collected at the sampling location, the daily value shall
be the result of that measurement.
    (iii) On days when no measurement is collected for the water
quality parameter at the sampling location, the daily value shall be
the daily value calculated on the most recent day on which the water
quality parameter was measured at the sampling location.
    (h) Modification of State treatment decisions for optimal corrosion
control and re-optimized corrosion control. Upon its own initiative or
in response to a request by a water system or other interested party, a
State may modify its determination of the optimal corrosion control
treatment under paragraph (d)(1), (d)(2), (d)(3), or (d)(4) of this
section, or optimal water quality control parameters under paragraph
(f)(1) or (f)(2) of this section. A request for modification by a
system or other interested party shall be in writing, explaining why
the modification is appropriate, and providing supporting
documentation. The State may modify its determination where it
concludes that such change is necessary to ensure that the water system
continues to optimize corrosion control treatment re-optimized
corrosion control treatment. A revised determination shall be made in
writing, set forth the new treatment requirements and/or water quality
parameters, explain the basis for the State's decision, and provide an
implementation schedule for completing the treatment modifications for
re-optimized corrosion control treatment.
    (i) Treatment decisions by the EPA in lieu of the State on optimal
corrosion control treatment and re-optimized corrosion control
treatment. (1) Pursuant to the procedures in Sec.  142.19 of this
chapter, the EPA Regional Administrator may review optimal corrosion
control treatment determinations made by a State under paragraph
(d)(1), (d)(2), (d)(3), (d)(4), (f)(1), (f)(2), or (h) of this section
and issue Federal treatment determinations consistent with the
requirements of those paragraphs where the Regional Administrator finds
that:
    (i) A State has failed to issue a treatment determination by the
applicable deadlines contained in Sec.  141.81.
    (ii) A State has abused its discretion in a substantial number of
cases or in cases affecting a substantial population; or
    (iii) The technical aspects of a State's determination would be
indefensible in an expected Federal enforcement action taken against a
water system.
    (j) Find-and-fix assessment for tap sample sites that exceed the
lead action level. The water system shall conduct the following steps,
when a tap sample site exceeds the lead action level under monitoring
conducted under Sec.  141.86.
    (1) Step 1. The water system shall sample at a new water quality
parameter site that is on the same size water main in the same pressure
zone and located within a half mile of the location with the action
level exceedance within 5 days of receiving the sample results. The
water system shall measure the following parameters:
    (i) pH;
    (ii) Alkalinity;
    (iii) Orthophosphate, when an inhibitor containing an
orthophosphate compound is used;
    (iv) Silica, when an inhibitor containing a silicate compound is
used; and
    (v) Water systems with an existing water quality parameter location
that meets the requirements of this section can conduct this sampling
at that location. All water systems required to meet optimal water
quality control parameters shall add new sites to the minimum number of
sites as described in Sec.  141.87(g).
    (2) Step 2. Water systems shall collect a follow-up sample at any
tap sample site that exceeds the action level within 30 days of
receiving the sample results. These follow-up samples may use different
sample volumes or different sample collection procedures to assess the
source of elevated lead levels. Samples collected under this section
shall be submitted to the State but shall not be included in the 90th
percentile calculation for compliance monitoring under Sec.  141.86. If
the water system is unable to collect a follow-up sample at a site, the
water system shall provide documentation to the State, explaining why
it was unable to collect a follow-up sample.
    (3) Step 3. Water systems shall evaluate the results of the
monitoring conducted under this paragraph to determine if either
localized or centralized adjustment of the optimal corrosion control
treatment (initial, modified, or re-optimized) is necessary and submit
the recommendation to the State within six months after the end of the
monitoring period in which the site(s) exceeded the lead action level.
Corrosion control treatment modification may not be necessary to
address every exceedance. Water systems shall note if the cause of the
elevated lead level if known in their recommendation to the State.
    (4) Step 4. The State shall approve the treatment recommendation or
specify a different approach within six months of completion of
paragraph (j), Step 3 of this section.
    (5) Step 5. If the State-approved treatment recommendation requires
the water system to adjust the optimal corrosion control treatment
process, the water system shall complete modifications to its corrosion
control

treatment within 12 months after completion of paragraph (j), Step 4 of
this section. Systems without corrosion control treatment required to
install optimal corrosion control treatment shall follow the schedule
in Sec.  141.81(e).
    (6) Step 6. Water systems adjusting its optimal corrosion control
treatment shall complete follow-up sampling (Sec.  141.86(d)(2) and
Sec.  141.87(c)) within 12 months after completion of paragraph (j),
Step 5 of this section.
    (7) Step 7. For water systems adjusting its optimal corrosion
control treatment, the State shall review the water system's
modification of corrosion control treatment and designate optimal water
quality control parameters (Sec.  141.82(f)(1)) within six months of
completion of paragraph (j), Step 6 of this section.
    (8) Step 8. For water systems adjusting its optimal corrosion
control treatment, the water system shall operate in compliance with
the State-designated optimal water quality control parameters (Sec.
141.82(g)(1)) and continue to conduct tap sampling (Sec. Sec.
141.86(d)(3) and 141.87(d)).
0
7. Revise Sec.  141.84 to read as follows:

Sec.  141.84  Lead service line inventory and replacement requirements.

    (a) Lead service line inventory. All water systems must develop and
maintain a publicly accessible inventory of lead service lines and
service lines of unknown materials in its distribution system. The
inventory must meet the following requirements:
    (1) Deadlines. All water systems must develop the initial inventory
by [DATE 3 YEARS AFTER DATE OF PUBLICATION IN THE Federal Register] and
submit it to the primacy agency in accordance with Sec.  141.90.
    (2) A water system shall use the information on lead and galvanized
steel that it is required to collect under Sec.  141.42(d) of this part
when conducting the inventory of service lines in its distribution
system for the initial inventory under paragraph (a)(1) of this
section. The water system shall also review the sources of information
listed below to identify service line materials for the initial
inventory. In addition, the water system shall seek to collect such
information where possible in the course of its normal operations
(e.g., checking service line materials when reading water meters or
performing maintenance activities):
    (i) All plumbing codes, permits, and records in the files of the
building department(s) which indicate the service line materials used
to connect water system- and customer-owned structures to the
distribution system.
    (ii) All water system records, including distribution system maps
and drawings, historical records on each service connection, meter
installation records, historical capital improvement or master plans,
and standard operating procedures.
    (iii) All inspections and records of the distribution system that
indicate the material composition of the service connections that
connect a structure to the distribution system.
    (iv) Any resource required by the State to asses service line
materials for structures built prior to 1989.
    (3) The initial inventory must include all service lines connected
to the public water distribution system regardless of ownership status
(e.g., where service line ownership is shared, the inventory would
include both the portion of the service line owned by the water system
and the customer-owned portion of the service line). Service lines
shall be categorized in the following manner:
    (i) Lead where either the water system portion, customer portion or
both portions of the service line are made of lead or where the
customer-owned portion is a galvanized pipe where the water system's
portion is or was a lead service line.
    (ii) Non-lead where both the water system portion and customer
portion are non-lead.
    (iii) Unknown where the service line material is only known to be
non-lead on either the water system portion or the customer portion of
the service line or the service line material for both portions of the
line is unknown.
    (4) Systems shall update the inventory on an annual basis to
address any lead service line replacement or service line material
identification at sites with lines characterized as unknown. The
updated inventory shall be submitted to the State on an annual basis.
    (5) Service lines listed as unknown in the initial inventory or the
updated inventory in paragraph (a)(4) of this section must be counted
as lead service lines for purposes of calculating lead service line
replacement rates as well as for issuing targeted public education to
consumers served by a lead or unknown service line.
    (i) These service lines must be considered lead service lines
unless they are demonstrated to be non-lead by records or physical
examination.
    (ii) Service lines of unknown material shall not be used for Tier 1
sampling sites.
    (iii) When a service line initially listed as a lead service line
on an inventory is later determined to be non-lead, the water system
must update its inventory and shall subtract it from the number of lead
service lines used to calculate lead service line replacement rates.
Such service lines must not be considered replaced.
    (iv) Service lines initially characterized as non-lead that are
later found to be made of lead on either the system or customer portion
shall be re-characterized as a lead service line and added to the
number of lead service lines used to calculate the lead service line
replacement rates.
    (6) The primacy agency may designate acceptable methods to
determine the service line material of unknown lines.
    (7) All water systems with lead service lines must make its
inventory publicly accessible.
    (i) The inventory must include a location identifier, such as a
street, intersection, or landmark, served by each lead service line.
Water systems are not required to list the exact address of each lead
service line.
    (ii) Water systems serving greater than 100,000 persons must make
the inventory available electronically.
    (b) Lead service line replacement plan. All water systems with lead
service lines in their distribution system shall, by [DATE 3 YEARS
AFTER PUBLICATION OF FINAL RULE IN Federal Register], submit a lead
service line replacement plan and lead service line inventory to the
primacy agency described in paragraph (a) of this section. The plan
must include procedures to conduct full lead service line replacement,
a strategy for informing customers before a full or partial lead
service line replacement, a lead service line replacement goal rate in
the event of a lead trigger level exceedance, a pitcher filter tracking
and maintenance system, a procedure for customers to flush service
lines and premise plumbing of particulate lead, and a funding strategy
for conducting lead service line replacements.
    (c) Operating procedures for replacing lead goosenecks, pigtails,
or connectors. (1) The water system must replace any lead gooseneck,
pigtail, or connector it owns when encountered during emergency repairs
or planned water system infrastructure work.
    (2) The water system must offer to replace a customer-owned lead
gooseneck, pigtail, or connector; however, the water system is not
required to bear the cost of replacement of the customer-owned parts.
    (3) The water system is not required to replace a customer-owned
lead gooseneck, pigtail, or connector if the customer objects to its
replacement.
    (4) The replacement of a lead gooseneck, pigtail, or connector does
not count for the purposes of meeting

the requirements for goal-based or mandatory lead service line
replacements, in accordance with paragraphs (e)(2) and (f)(2) of this
section, respectively.
    (5) Upon replacement of any gooseneck, pigtail, or connector that
is attached to a lead service line, the water system must follow risk
mitigation procedures specified in 141.85(e)(5)(ii).
    (d) Requirements for conducting lead service line replacement that
may result in partial replacement. (1) Any water system that plans to
partially replace a lead service line (e.g., replace only the portion
of a lead service line that it owns) in coordination with planned
infrastructure work must provide notice to the owner of the lead
service line, or the owner's authorized agent, as well as non-owner
resident(s) served by the lead service line at least 45 days prior to
the replacement. The notice must explain that the system will replace
the portion of the line it owns and offer to replace the portion of the
service line not owned by the water system. The water system is not
required to bear the cost of replacement of the portion of the lead
service line not owned by the water system.
    (i) The water system must provide notification explaining that
consumers may experience a temporary increase of lead levels in their
drinking water due to the replacement, information about the health
effects of lead, and actions consumers can take to minimize their
exposure to lead in drinking water. In instances where multi-family
dwellings are served by the lead service line to be partially replaced,
the water system may elect to post the information at a conspicuous
location instead of providing individual notification to all residents.
    (ii) The water system must provide information about service line
flushing in accordance with Sec.  141.84(b).
    (iii) The water system must provide the consumer with a pitcher
filter certified to remove lead, three months of replacement
cartridges, and instructions for use. If the lead service line serves
more than one residence or non-residential unit (e.g., a multi-unit
building), the water system must provide a pitcher filter, three months
of replacement cartridges and use instructions to every residence in
the building.
    (iv) The water system must take a follow up tap sample between
three months and six months after completion of any partial lead
service line replacement. The water system must provide the results of
the sample to the consumer in accordance with Sec.  141.85(d).
    (2) Any water system that replaces the portion of the lead service
line it owns due to an emergency repair, must provide notice and risk
mitigation measures to the customer served by the lead service line
within 24 hours. The water system must provide notification and risk
mitigation measure in accordance with (d)(1)(i)-(iv) of this section.
    (3) A water system must replace the lead service line it owns when
it is notified that the customer has replaced the customer-owned
portion of the lead service line. When a water system is notified by
the customer that he or she intends to replace the customer portion of
the lead service line the water system has 45 days from the day of
their notification to conduct the replacement of the system-owned
portion. The water system must make a good faith effort to coordinate
simultaneous replacement. The water system must provide notification
and risk mitigation measure in accordance with (d)(1)(i)-(iv) of this
section.
    (4) When a water system is notified by the customer that he or she
has replaced the customer-owned portion and that replacement has
occurred within the previous 3 months, the water system must replace
its portion within 45 days from the day of their notification. The
water system must provide notification and risk mitigation measures in
accordance with (d)(1)(i)-(iv) of this section.
    (5) When a water system is notified by the customer that he or she
has replaced the customer-owned portion and the replacement has
occurred more than three months in the past, the water system is not
required to complete the lead service line replacement of the system-
owned portion.
    (e) Requirements for conducting full lead service line replacement.
(1) Any water system that conducts a full lead service line replacement
(e.g., replace both the portion of a lead service line owned by the
customer and by the water system) must provide notice to the owner of
the lead service line, or the owner's authorized agent, as well as non-
owned resident(s) served by the lead service line within 24 hours of
the replacement.
    (i) The water system must provide notification explaining that
consumers may experience a temporary increase of lead levels in their
drinking water due to the replacement, information about the health
effects of lead, and actions consumers can take to minimize their
exposure to lead in drinking water. In instances where multi-family
dwellings are served by the lead service line to be replaced, the water
system may elect to post the information at a conspicuous location
instead of providing individual notification to all residents.
    (ii) The water system must provide information about service line
flushing in accordance with Sec.  141.84(b).
    (iii) The water system must provide the consumer with a pitcher
filter certified to remove lead, three months of replacement
cartridges, and instructions for use. If the lead service line serves
more than one residence or non-residential unit (e.g., a multi-unit
building), the water system must provide a pitcher filter, three months
of replacement cartridges and use instructions to every residence in
the building.
    (iv) The water system must take a follow up tap sample between
three months and six months after completion of any partial lead
service line replacement. The water system must provide the results of
the sample to the consumer in accordance with Sec.  141.85(d).
    (f) Water systems whose 90th percentile lead level from tap samples
is above the trigger level but at or below the action level. Water
systems whose 90th percentile lead level from tap samples taken
pursuant to Sec.  141.86 is above the lead trigger level but at or
below the lead action level must conduct goal-based lead service line
replacement.
    (1) Within six months following completion of the initial
invention, pursuant to paragraph (a) of this section, water systems
serving over 10,000 persons must determine a goal rate at which it will
replace lead service lines after their 90th percentile lead level
exceeds of the trigger level but is below the lead action level. This
lead service line replacement goal rate must be approved by the State
pursuant to (b) of this section.
    (2) Water systems must apply the goal replacement rate to the
initial number of lead service lines, including service lines of
unknown material, in the water system's LSL inventory. If the water
system at any time determines a service line of unknown material is
non-lead, the water system may subtract it from the initial number of
lead service lines used for calculating the lead service line
replacement rate.
    (3) Lead service line replacement must be conducted in accordance
with the requirements of paragraphs (d) or (e) of this section.
    (4) Only full lead service line replacements count towards a water
system's annual replacement goal. Partial lead service line
replacements do not count towards the goal.

    (5) The water system must provide notification to customers with
lead service lines as required in Sec.  141.85(f).
    (6) Any water system that fails to meet its lead service line
replacement goal must:
    (i) Conduct public outreach activities pursuant to Sec.  141.85(g)
until either the water system meets its replacement goal, or tap
sampling shows the 90th percentile of lead is below the trigger level
for two consecutive monitoring periods.
    (ii) Recommence its goal-based lead service line replacement
program pursuant to this paragraph if the 90th percentile lead value
anytime thereafter exceeds the lead trigger level.
    (7) The first year of lead service line replacement shall begin on
the first day following the end of the monitoring period in which the
lead action level was exceeded. If monitoring is required annually or
less frequently, the end of the monitoring period is September 30 of
the calendar year in which the sampling occurs. If the State has
established an alternate monitoring period, then the end of the
monitoring period will be the last day of that period.
    (8) Pursuant to the procedures in Sec.  142.19, the EPA Regional
Administrator may review the lead service line replacement goal rate
determination made by a State under paragraph Sec.  141.84(b) of this
section and issue a Federal goal-based lead service line replacement
rate determination where the Regional Administrator finds that a higher
goal-based lead service line replacement rate is feasible for a water
system.
    (g) Lead service line replacement for water systems that exceed the
lead action level in tap samples. Water systems that exceed the lead
action level in tap samples taken pursuant to Sec.  141.86 must replace
full lead service lines at a minimum annual rate.
    (1) Water systems must annually replace three percent of the
initial number of lead service lines in the inventory, including
service lines of unknown material at time of the action level
exceedance. The water system must meet the replacement rate with full
lead service line replacements but is not required to bear the cost of
removal of the portion of the lead service line it does not own. If the
water system later determines a service line of unknown material is
non-lead, the water system may subtract it from the initial number of
lead service lines used for calculating the lead service line
replacement rate.
    (2) Lead service line replacement must be conducted in accordance
with the requirements of paragraphs (c) or (d) of this section.
    (3) Only full lead service line replacements count towards a water
system's mandatory replacement rate. Partial lead service line
replacements do not count towards the mandatory replacement rate.
    (4) Water systems must conduct notification to customers with lead
service lines as required in Sec.  141.85(f).
    (5) Community water systems serving 10,000 or fewer persons may
elect to conduct a corrosion control treatment or point-of-use filter
compliance approach as described in section Sec.  141.93 instead of
lead service line replacement. Non-transient non-community water
systems may elect to conduct a corrosion control treatment, point-of-
use filter compliance approach, or choose a replacement of lead-bearing
plumbing approach, as described in section Sec.  141.93.
    (6) A water system may cease mandatory lead service line
replacement when its lead 90th percentile level, calculated under Sec.
141.80(c)(4), is at or below the lead action level during each of four
consecutive monitoring periods. If first draw tap samples collected in
any such system thereafter exceed the lead action level, the system
shall recommence mandatory lead service line replacement.
    (7) The water system may cease mandatory lead service line
replacement if it obtains refusal to conduct full lead service line
replacement from every customer in its distribution area served by a
lead service line on the customer's portion. If the water system
exceeds the action level again, it must reach out to any customers
served by a lead service line where there has been a change in
residents with an offer to replace the customer-owned portion. The
water system is not required to bear the cost of replacement of the
customer-owned lead service line.
    (8) The first year of lead service line replacement shall begin on
the first day following the end of the monitoring period in which lead
action level was exceeded under paragraph (a) of this section. If
monitoring is required annually or less frequently, the end of the
monitoring period is September 30 of the calendar year in which the
sampling occurs. If the State has established an alternate monitoring
period, then the end of the monitoring period will be the last day of
that period.
    (9) The State shall require a system to replace lead service lines
on a shorter schedule than that required by this section, taking into
account the number of lead service lines in the system, where a shorter
replacement schedule is feasible. The State shall make this
determination in writing and notify the system of its finding within
six months after the system is required to begin lead service line
replacement based on monitoring referenced in paragraph (f) of this
section.
    (h) State reporting to demonstrate compliance. To demonstrate
compliance with paragraphs (a) through (f) of this section, a system
shall report to the State the information specified in Sec.  141.90(e).
0
8. Amend Sec.  141.85 by:
0
a. Revising the introductory text, paragraphs (a)(1)(ii),
(b)(2)(ii)(B), and (b)(2)(ii)(B)(1);
0
b. Adding paragraph (b)(2)(ii)(B)(7) and removing paragraph
(b)(2)(ii)(C);
0
c. Revising paragraphs (d)(1), (2), and (4) ; and
0
d. Adding paragraphs (e), (f), and (g).
    The revisions and additions read as follows:

Sec.  141.85  Public education and supplemental monitoring
requirements.

    All water systems must deliver a consumer notice of lead tap water
monitoring results to persons served by the water system at sites that
are tested, as specified in paragraph (d) of this section. A water
system with lead service lines must deliver public education materials
to persons with a lead service line as specified in paragraph (e) and
(f) of this section. All water systems must conduct annual outreach to
healthcare providers and caregivers as outlined in section (g) of this
section. A water system that exceeds the lead action level based on tap
water samples collected in accordance with Sec.  141.86 shall deliver
the public education materials contained in paragraph (a) of this
section and in accordance with the requirements in paragraph (b) of
this section. Water systems that exceed the lead action level must
sample the tap water of any customer who requests it in accordance with
paragraph (c) of this section.
    (a) * * *
    (1) * * *
    (ii) Health effects of lead. Exposure to lead can cause serious
health effects in all age groups. Infants and children who drink water
containing lead could have decreases in IQ and attention span and
increases in learning and behavior problems. Lead exposure among women
who are pregnant increases prenatal risks. Lead exposure among women
who later become pregnant has similar risks if lead stored in the
mother's bones is released during pregnancy. Recent science suggests
that adults who drink water containing lead have increased

risks of heart disease, high blood pressure, kidney or nervous system
problems.
* * * * *
    (b) * * *
    (2) * * *
    (ii) * * *
    (B) * * *
    (1) Schools, child care facilities and school boards.
* * * * *
    (7) Obstetricians-Gynecologists and Midwives.
    (d) Notification of results. (1) Reporting requirement. All water
systems must provide a notice of the individual tap results from lead
tap water monitoring carried out under the requirements of Sec.  141.86
to the persons served by the water system at the specific sampling site
from which the sample was taken (e.g., the occupants of the residence
where the tap was tested).
    (2) Timing of notification. A water system must provide the
consumer notice as soon as practical, in accordance to the following
timeframes:
    (i) For individual samples that do not exceed the lead action
level, no later than 30 days after the water system learns of the tap
monitoring results.
    (ii) For individual samples that exceed the lead action level, no
later than 24 hours after the water system learns of the tap monitoring
results.
* * * * *
    (4) Delivery. (i) For lead tap sample results that do not exceed
the lead action level of 0.015 mg/L, the water systems must provide
consumer notice to persons served at the tap that was tested, either by
mail or by another method approved by the State. For example, upon
approval by the State, a non-transient non-community water system could
post the results on a bulletin board in the facility to allow users to
review the information. The system must provide the notice to
consumers, including customers at taps where sampling was conducted.
    (ii) For tap sample results that exceed the lead action level of
0.015 mg/L, the water systems must provide consumer notice to consumers
served at the tap that was tested electronically or by phone or another
method approved by the State.
    (e) Notification of lead service line. (1) Notification
requirements. All water systems with lead service lines must provide
notification to all consumers with a lead service line or a service
line of unknown material informing them they have a lead service line
or a service line of unknown material.
    (2) Timing of notification. A water system must provide the initial
notification within 30 days of completion of the lead service line
inventory required under Sec.  141.84 and repeat the notification on an
annual basis until the customer no longer has a lead service line. For
new customers, water systems shall provide the notice at the time of
service initiation.
    (3) Content. (i) Consumers with a confirmed lead service line. The
notice must include a statement that the consumer's service line is
lead, an explanation of the health effects of lead, steps consumers can
take to reduce exposure to lead in drinking water, information about
opportunities to replace lead service lines and information about
programs that provide innovative financing solutions to assist
consumers with replacement of their portion of a lead service line, and
a statement that the water system is required to replace its portion of
a lead service line when the consumer notifies them they are replacing
their owned portion of the lead service line.
    (ii) Customers with a service line of unknown material. The notice
must include a statement that the customer's service line is of unknown
material that may be lead, an explanation of the health effects of
lead, steps customers can take to reduce exposure to lead in drinking
water and information about opportunities to verify the material of the
service line.
    (4) Delivery. The notice must be provided to persons served by a
lead service line or service line of unknown material, either by mail
or by another method approved by the primacy agency.
    (5) Notification due to a disturbance of a lead service line. (i)
Water systems that cause disturbance to a lead service line that
results in the water being shut off, and without conducting a partial
or full lead service line replacement, must provide the consumer with
information about the potential for elevated lead in drinking water a
result of the disturbance as well as a flushing procedure to remove
particulate lead.
    (ii) If the disturbance of a lead service line results from the
replacement of the water meter or gooseneck, pigtail, or connector, the
water system must comply with the requirements in paragraph (e)(5)(i)
of this section as well as provide the consumer with a pitcher filter
certified to remove lead, instructions to use the filter, and three
months of filter replacement cartridges.
    (iii) A water system that conducts a partial or full lead service
line replacement must comply with the requirements in paragraph
(e)(5)(i) of this section as well as provide the consumer with a
pitcher filter certified to remove lead, instructions to use the
filter, and three months of filter replacement cartridges.
    (iv) The water system must comply with the requirements of
paragraphs (e)(5) of this section before the consumer's water is turned
back on after it has been shut off by the water system.
    (f) Notification of exceedance of the lead trigger level. (1) All
water systems with lead service lines that exceed the lead trigger
level of 0.010 mg/L must provide customers that have a lead service
line information regarding the water system's goal-based lead service
line replacement program and opportunities for replacement of the lead
service line.
    (2) Timing. Waters Systems shall send notification within 30 days
of the end of the monitoring period in which the trigger level
exceedance occurred. Water systems must repeat the notification
annually until the results of sampling conducted under Sec.  141.86 is
at or below the lead trigger level.
    (3) Delivery. The notice must be provided to persons served by a
lead service line, either by mail or by another method approved by the
State.
    (g) Outreach activities for failure to meet the lead service line
replacement goal. (1) In the first year that a water system that does
not meet its annual lead service line replacement goal as required
under Sec.  141.84, it must conduct one outreach activity from the
following list in the following year until the water system meets it
replacement goal or until tap sampling shows that the 90th percentile
for lead is at or below the trigger level of 0.010 mg/L. Any water
system that thereafter continues to fail to meet its lead service line
replacement goal must conduct two outreach activities per year from the
following list:
    (i) Conduct social media campaign.
    (ii) Contact organizations representing plumbers and contractors by
mail to provide information about lead in drinking water including
health effects, sources of lead, and the importance of using lead free
plumbing materials.
    (iii) Send certified mail to customers with a lead service line to
inform them about the water system's goal-based lead service line
replacement program and opportunities for replacement of the lead
service line.
    (iv) Conduct a town hall meeting or participate in a community
event to provide information about its lead service line replacement
program and distribute public education materials.
    (v) Visit targeted customers to discuss the lead service line
replacement program and opportunities for replacement.

    (vi) In the case where all lead service line customers refuse to
participate in the lead service line replacement program, obtain a
signed letter from each customer stating such refusal.
    (h) Public education to local and State health agencies. (1) All
water systems shall provide public education materials that meet the
content requirements of paragraph (a)(1) of this section.
    (2) Timing. Water systems must send public education materials no
later than January 15 of each calendar year.
    (3) Delivery. Water systems shall send public education materials
or provide public education by mail or by another method approved by
the State.
0
9. Amend Sec.  141.86 by:
0
a. Revising paragraphs (a), (b)(1), and (b)(2);
0
b. Reserving paragraph (b)(3);
0
c. Revising paragraphs (d) and (e);
0
d. Revising the heading of paragraph (f); and
0
e. Adding paragraphs (h) and (i).
    The revisions and additions read as follows:

Sec.  141.86  Monitoring requirements for lead and copper in tap water.

    (a) Sample site location. (1) By the applicable date for
commencement of monitoring under paragraph (d)(1) of this section, each
water system shall complete a lead service line inventory of its
distribution system and identify a pool of targeted sampling sites that
meet the requirements of this section, and which is sufficiently large
enough to ensure that the water system can collect the number of lead
and copper tap samples required in paragraph (c) of this section. Water
systems with lead service lines or service lines of unknown material
must re-evaluate the tap sampling locations based on a lead service
line inventory conducted under Sec.  141.84(a), which must be updated
annually thereafter, including identifying any changes to the sampling
locations. Sites may not include faucets that have point-of-use (POU)
or point-of-entry (POE) treatment devices designed to remove inorganic
contaminants, except for systems monitoring under Sec.  141.93 (Small
System Compliance Flexibility). Lead and copper sampling results for
systems monitoring under 141.93(c)(3) and (d)(3) may not be used for
the purposes of meeting the criteria for reduced monitoring specified
in (d)(4) of this section.
    (2) A water system shall use the information on lead, copper, and
galvanized steel that is required to be collected under Sec.  141.42(d)
(special monitoring for corrosivity characteristics) when conducting a
materials evaluation. A water system shall use the information on lead
service lines that is required to be collected under Sec.  141.84(a) to
identify potential lead service line sampling sites. When an evaluation
of the information collected pursuant to Sec.  141.42(d) and 141.84(a)
is insufficient to locate the requisite number of lead and copper
sampling sites that meet the targeting criteria in paragraph (a) of
this section, the water system shall review the sources of information
listed below to identify a sufficient number of sampling sites. In
addition, the system shall seek to collect such information where
possible in the course of its normal operations (e.g., checking service
line materials when reading water meters or performing maintenance
activities):
    (i) All plumbing codes, permits, and records in the files of the
building department(s) that indicate the plumbing materials that are
installed within publicly and privately-owned structures connected to
the distribution system;
    (ii) All inspections and records of the distribution system that
indicate the material composition of the service connections that
connect a structure to the distribution system; and
    (iii) All existing water quality information, which includes the
results of all prior analyses of the system or individual structures
connected to the system, indicating locations that may be particularly
susceptible to high lead or copper concentrations.
    (3) The sampling sites selected for a community water system's
sampling pool (``Tier 1 sampling sites'') shall consist of single-
family structures that are served by a lead service line. When
multiple-family residences comprise at least 20 percent of the
structures served by a water system, the system may include these types
of structures in its Tier 1 sampling pool, if served by a lead service
line. Service lines of unknown material must not be used as Tier 1
sampling sites.
    (4) Any community water system with insufficient Tier 1 sampling
sites shall complete its sampling pool with ``Tier 2 sampling sites,''
consisting of buildings, including multiple-family residences that are
served by a lead service line.
    (5) Any community water system with insufficient Tier 1 and Tier 2
sampling sites shall complete its sampling pool with ``Tier 3 sampling
sites,'' consisting of single-family structures that contain copper
pipes with lead solder.
    (6) A community water system with insufficient Tier 1, Tier 2, and
Tier 3 sampling sites shall complete its sampling pool with ``Tier 4
sampling sites,'' consisting of single-family structures or buildings,
including multiple family residences that are representative of sites
throughout the distribution system. For the purpose of this paragraph,
a representative site is a site in which the plumbing materials used at
that site would be commonly found at other sites served by the water
system.
    (7) The sampling sites selected for a non-transient non-community
water system (``Tier 1 sampling sites'') shall consist of buildings
that are served by a lead service line. Service lines of unknown
material must not be used as Tier 1 sampling sites.
    (8) A non-transient non-community water system with insufficient
Tier 1 sites that meet the targeting criteria in paragraph (a)(7) of
this section shall complete its sampling pool with ``Tier 3 sampling
sites,'' consisting of sampling sites that contain copper pipes with
lead solder.
    (9) A non-transient non-community water system with insufficient
Tier 1 and Tier 3 sampling sites shall complete its sampling pool with
``Tier 4 sampling sites,'' consisting of sampling sites that are
representative of sites throughout the distribution system. For the
purpose of this paragraph, a representative site is a site in which the
plumbing materials used at that site would be commonly found at other
sites served by the water system.
    (10) Any water system whose distribution system contains lead
service lines shall collect all samples for monitoring under this
section from sites served by a lead service line. A water system that
cannot identify a sufficient number of sampling sites served by lead
service lines shall still collect samples from every site served by a
lead service line, and collect the remaining samples in accordance with
tiering requirements under (a)(2)(iii) of this section.
    (b) Sample collection methods. (1) All tap samples for lead and
copper collected in accordance with this subpart, with the exception of
samples collected under paragraph (b)(5) and paragraph (h) of this
section, shall be first draw samples.
    (2) Each first-draw tap sample for lead and copper shall be one
liter in volume and have stood motionless in the plumbing system of
each sampling site for at least six hours. Bottles used to collect
these samples shall be wide-mouth one-liter sample bottles. First-draw
samples from residential housing shall be collected from the cold-water
kitchen tap or bathroom sink tap. First-draw samples from a
nonresidential building shall be one liter in volume and collected at
an interior tap from which water is typically drawn for consumption.
Non-first-draw samples

collected in lieu of first-draw samples pursuant to paragraph (b)(5) of
this section shall be one liter in volume and shall be collected at an
interior tap from which water is typically drawn for consumption.
First-draw samples may be collected by the system or the system may
allow residents to collect first-draw samples after instructing the
residents of the sampling procedures specified in this paragraph.
Sampling instructions provided to customers shall not include
instructions for aerator removal and cleaning or flushing of taps prior
to the start of the minimum six-hour stagnation period. To avoid
problems of residents handling nitric acid, acidification of first-draw
samples may be done up to 14 days after the sample is collected. After
acidification to re-solubilize the metals, the sample must stand in the
original container for the time specified in the approved EPA method
before the sample can be analyzed. If a system allows residents to
perform sampling, the system may not challenge, based on alleged errors
in sample collection, the accuracy of sampling results.
* * * * *
    (d) Timing of monitoring (1) Initial tap sampling. (i) All water
systems with lead service lines deemed optimized under Sec.
141.81(b)(3) and systems that did not conduct monitoring that meets the
requirements of this section prior to the compliance date of this
section must begin the first six-month monitoring period on January 1
in the year following the compliance date of this section.
    (ii) Systems that conducted monitoring that meets the requirements
of this section prior to the effective date of this section shall
conduct the next round of monitoring on the following schedules based
on the results of that monitoring:
    (A) Systems that exceed the action levels for lead or copper shall
begin the first six-month monitoring period on January 1 in the year
following the effective date of this section.
    (B) Systems that exceed the lead trigger level and meet the lead
and copper action levels shall begin the first annual monitoring period
on January 1 in the year following the effective date of this section.
Samples shall be analyzed for lead on an annual basis. Samples shall be
analyzed for copper on a triennial basis. Systems without corrosion
control treatment that meet the lead trigger level in three annual
monitoring periods may reduce monitoring in accordance with paragraph
(d)(4) of this section.
    (C) Lead service line systems that do not exceed the lead trigger
level and copper action level shall begin the next annual monitoring
period on January 1 of the year following the effective date of this
section. Samples shall be analyzed for lead on an annual basis. Samples
shall be analyzed for copper on a triennial basis. Systems that do not
exceed the lead trigger level in three annual monitoring periods may
reduce monitoring in accordance with paragraph (d)(4) of this section.
    (D) Systems without lead service lines that do not exceed the lead
trigger level and the copper action level shall begin the next
triennial monitoring period within three calendar years of the previous
round.
    (2) Monitoring after installation of initial or re-optimized
corrosion control treatment and installation of source water treatment.
(i) Any water system that installs or re-optimizes corrosion control
treatment shall continue to monitor for lead and copper every six
months until the State specifies water quality parameter values for
optimal corrosion control.
    (ii) Any system that re-optimizes corrosion control treatment as a
result of exceeding the lead trigger level shall monitor annually for
lead. Samples shall be analyzed for copper on a triennial basis. Small
and medium-size systems for which the State did not specify water
quality control parameters under Sec.  141.82 that meet the lead
trigger level in three annual monitoring periods may reduce monitoring
in accordance with paragraph (d)(4) of this section.
    (iii) Any system that installs source water treatment pursuant to
Sec.  141.83(a)(3) shall monitor every six months until the system
meets the lead and copper action levels for two consecutive six-month
monitoring periods. Systems that meet the lead and copper action
levels, but not the lead trigger level for two consecutive 6-month
monitoring periods may reduce monitoring in accordance with paragraph
(d)(4) of this section.
    (3) Monitoring after State specifies water quality parameter values
for optimal corrosion control treatment. (i) After the State specifies
the values for water quality control parameters under Sec.  141.82(f),
all large and any small or medium size systems that exceeded an action
level shall continue to monitor every six months until the system does
not exceed the lead and copper action levels for two consecutive 6-
month monitoring periods. Systems that do not exceed the lead and
copper action levels, but exceed the lead trigger level (10
[micro]g/L) shall monitor annually at the standard number of sites
listed in (c) of this section. Systems that do not exceed the lead
trigger level and copper action level in three annual monitoring
periods may reduce monitoring in accordance with paragraph (d)(4) of
this section.
    (ii) Any small or medium size system which exceeded the lead
trigger level for which the State has specified water quality parameter
values for optimal corrosion control treatment shall continue to
monitor every six months until the system meets the lead and copper
action levels for two consecutive 6-month monitoring periods. Systems
that do not exceed the lead and copper action levels, but exceed the
lead trigger level shall monitor annually at the standard number of
sites listed in paragraph (c) of this section. Systems that do not
exceed the lead trigger level and copper action level in three annual
monitoring periods may reduce monitoring in accordance with paragraph
(d)(4) of this section.
    (4) Reduced Monitoring based on 90th percentile lead levels. (i)
(A) A small or medium-size system that meets the lead trigger level and
copper action level under paragraph (d)(1)(i) of this section may
reduce the frequency of sampling to annual monitoring. This monitoring
shall begin in the calendar year immediately following the end of the
second consecutive 6-month monitoring period.
    (B) A small or medium-size water system that meets the lead trigger
level and copper action level under paragraph (d)(1)(ii)(D) of this
section may reduce the number of samples in accordance with paragraph
(c) of this section and reduce the sampling frequency to triennial
monitoring. This monitoring shall begin during the calendar year three
years after the monitoring conducted under paragraph (d)(1)(ii)(D) of
this section. A small or medium system collecting fewer than five
samples as specified in paragraph (c) of this section that meets the
lead trigger level and copper action level under paragraph
(d)(1)(ii)(D) of this section may reduce the sampling frequency to
triennial monitoring. In no case may the system reduce the number of
samples below the minimum of one sample per available tap. This
monitoring shall begin during the calendar year three years after the
monitoring conducted under paragraph (d)(1)(ii)(D) of this section.
    (C) Any small or medium-size system without corrosion control
treatment that exceeds the lead trigger level, but meets copper action
level, shall collect the standard number of samples on an annual basis.
This sampling shall begin in the calendar year following the monitoring
conducted under paragraph (d)(1)(i) or (d)(1)(ii)(B) of this section. A
small or medium system collecting

fewer than five samples as specified in paragraph (c) of this section
that meets the lead trigger level and copper action level under
paragraph (d)(1)(i) or (d)(1)(ii)(D) of this section shall collect the
standard number of samples on an annual basis. In no case may the
system reduce the number of samples below the minimum of one sample per
available tap. This sampling shall begin in the calendar year following
the monitoring conducted under paragraph (d)(1)(i) or (d)(1)(ii)(B) of
this section.
    (D) Any small or medium-size system with corrosion control
treatment that exceeds the lead trigger level but meets the lead and
copper action levels and is not required by the State to make changes
to the corrosion control treatment as a result of the re-optimization
assessment under Sec.  141.82, shall collect the standard number of
samples on an annual basis. This sampling shall begin in the calendar
year following the monitoring conducted under paragraph (d)(1)(i) or
(d)(1)(ii)(B) of this section. A small or medium system collecting
fewer than five samples as specified in paragraph (c) of this section
that meets the lead trigger level and copper action level under
paragraph (a)(ii)(D) of this section shall collect the standard number
of samples on an annual basis. In no case may the system reduce the
number of samples below the minimum of one sample per available tap.
This monitoring shall begin in the calendar year following the
monitoring conducted under paragraph (d)(1)(i) or (d)(1)(ii)(B) of this
section.
    (ii) (A) Any water system that meets the lead trigger level and
copper action level and maintains the range of values for the water
quality parameters for optimal corrosion control treatment specified by
the State under Sec.  141.82(f) during each of two consecutive six-
month monitoring periods may reduce the sampling frequency for the
standard number of samples to annual monitoring. This sampling shall
begin in the calendar year immediately following the end of the second
consecutive six-month monitoring period. The State shall review
monitoring, treatment, and other relevant information submitted by the
water system in accordance to Sec.  141.90 and shall notify the system
in writing when it determines the system is eligible to commence
reduced monitoring pursuant to this paragraph. The State shall review,
and where appropriate, revise its determination when the system submits
new monitoring or treatment data, or when other data relevant to the
frequency of tap sampling becomes available.
    (B) Any water system that exceeds the lead trigger level but meets
the lead and copper action levels and maintains the range of values for
the water quality parameters reflecting optimal corrosion control
treatment specified by the State under Sec.  141.82(f) during each of
two consecutive six-month monitoring periods may reduce the monitoring
frequency at the standard number of sites to annual monitoring. This
sampling shall begin in the calendar year immediately following the end
of the second consecutive 6-month monitoring period. The State shall
review monitoring, treatment, and other relevant information submitted
by the water system in accordance to Sec.  141.90 and shall notify the
system in writing when it determines the system is eligible to commence
reduced monitoring pursuant to this paragraph. The State shall review,
and where appropriate, revise its determination when the system submits
new monitoring or treatment data, or when other data relevant to the
frequency of monitoring becomes available.
    (iii) (A) A small or medium-size water system that meets the lead
trigger level and copper action level under paragraph (d)(4)(i)(D) of
this section may reduce the number of samples in accordance with
paragraph (c) of this section and reduce the monitoring frequency to
triennial monitoring. This sampling should begin during the calendar
year three years after the monitoring conducted under paragraph
(d)(ii)(D) of this section. A small or medium system collecting fewer
than five samples as specified in paragraph (c) of this section that
meets the lead trigger level and copper action level under paragraph
(d)(ii)(D) of this section may reduce the monitoring frequency to
triennial monitoring. This monitoring should begin during the calendar
year three years after the monitoring conducted under paragraph
(d)(ii)(D) of this section. In no case may the system reduce the number
of samples below the minimum of one sample per available tap. This
sampling should begin during the calendar year three years after the
monitoring conducted under paragraph (a)(ii)(D) of this section.
    (B) Any small or medium-size system monitoring under Sec.
141.86(d)(4)(i)(A) or (B) that meets the lead trigger level and the
copper action level in three consecutive rounds of annual monitoring
may reduce the number of samples in accordance with paragraph (c) of
this section and reduce the sampling frequency to triennial monitoring.
This sampling should begin during the calendar year three years after
the monitoring conducted under paragraph (a)(ii)(D) of this section. A
small or medium system collecting fewer than five samples as specified
in paragraph (c) of this section that meets the lead trigger level and
copper action level under paragraph (a)(ii)(D) of this section may
reduce the sampling frequency to triennial monitoring. In no case may
the system reduce the number of samples below the minimum of one sample
per available tap. This monitoring must begin during the calendar year
three years after the monitoring conducted under paragraph (a)(ii)(D)
of this section.
    (iv) A water system that reduces the frequency of sampling shall
collect these samples from representative sites included in the pool of
targeted sampling sites identified in paragraph (a) of this section.
Systems monitoring annually or less frequently shall conduct the lead
and copper tap sampling during the months of June, July, August, or
September unless the State has approved a different monitoring period
in accordance with paragraph (d)(iv)(A) of this section.
    (A) The State at its discretion may approve a different period for
conducting the lead and copper tap sampling for systems collecting
samples at a reduced frequency. Such a period shall be no longer than
four consecutive months and must represent a time of normal operation
where the highest levels of lead are most likely to occur. For a non-
transient non-community water system that does not operate during the
months of June through September and for which the period of normal
operation where the highest levels of lead are most likely to occur is
not known, the State shall designate a period that represents normal
operation for the system. This monitoring shall begin during the period
approved or designated by the State in the calendar year immediately
following the end of the second 6-month monitoring period for systems
initiating annual monitoring and during the 3-year period following the
end of the third consecutive year of annual monitoring for systems
initiating triennial monitoring.
    (B) Systems monitoring annually that have been collecting samples
during the months of June through September and that receive State
approval to alter their monitoring period under paragraph (d)(4)(iv)(A)
of this section must collect their next round of samples during a time
period that ends no later than 21 months after the previous round of
sampling. Systems monitoring triennially that have been collecting
samples during the month of June through September and receive State
approval to alter their sampling

collection period as per paragraph (d)(4)(iv)(A) of this section must
collect their next round of samples during a time period that ends no
later than 45 months after the previous monitoring period. Subsequent
monitoring must be conducted annually or triennially, as required by
this section. Small systems with waivers, granted pursuant to paragraph
(g) of this section that have been collecting samples during the months
of June through September and receive State approval to alter their
monitoring period as per paragraph (d)(4)(iv)(A) of this section must
collect their next round of samples before the end of the 9-year
period.
    (v) Any water system that demonstrates for two consecutive 6-month
monitoring periods that its 90th percentile lead level, calculated
under Sec.  141.80(c)(4), is less than or equal to 0.005 mg/L and the
90th percentile copper level, calculated under Sec.  141.80(c)(4), is
less than or equal to 0.65 mg/L may reduce the number of samples in
accordance with paragraph (c) of this section and reduce the frequency
of monitoring to triennial monitoring.
    (vi)(A)(1) A small or medium-size water system on reduced triennial
monitoring that exceeds the lead or copper action level shall resume
monitoring in accordance with paragraph (d)(3)(i) of this section and
collect the number of samples specified for standard monitoring under
paragraph (c) of this section. Such a system shall also conduct water
quality parameter monitoring in accordance with Sec.  141.87(b), (c) or
(d) (as appropriate) during the monitoring period in which it exceeded
the action level. Any such water system may resume annual monitoring
for lead and copper and discontinue water quality parameter monitoring
in accordance with Sec.  141.87(b), (c) or (d) (as appropriate) after
it has completed two consecutive 6-month rounds of monitoring that meet
the criteria of (d)(4)(i)(A) of this section, and may resume triennial
monitoring for lead and copper at the reduced number of sites after it
demonstrates through subsequent rounds of monitoring that it meets the
criteria of either paragraph (d)(4)(iii)(B) or (d)(4)(v) of this
section.
    (2) A small or medium-size water system subject to annual
monitoring that exceeds the lead or copper action level shall resume
sampling in accordance with paragraph (d)(3)(i) of this section. Such a
system shall also conduct water quality parameter monitoring in
accordance with Sec.  141.87(b), (c) or (d) (as appropriate) during the
monitoring period in which it exceeded the action level. Any such
system may resume annual monitoring for lead and copper and discontinue
water quality parameter monitoring in accordance with Sec.  141.87(b),
(c) or (d) (as appropriate) after it has completed two subsequent
consecutive 6-month rounds of monitoring that meet the criteria of
(d)(4)(i)(A) of this section, and may resume triennial monitoring for
lead and copper at the reduced number of sites after it demonstrates
through subsequent rounds of monitoring that it meets the criteria of
either paragraph (d)(4)(iii)(B) or (d)(4)(v) of this section.
    (3) A small or medium-size system subject to reduced triennial
monitoring that exceeds the lead trigger level shall resume sampling in
accordance with (d)(4)(ii)(B) of this section and collect the number of
samples specified for standard monitoring under paragraph (c) of this
section. If required by the State, such a system shall also conduct
water quality parameter monitoring in accordance with Sec.  141.87(b),
(c) or (d) (as appropriate) during the monitoring period in which it
exceeded the action level. Any such system may resume triennial
monitoring for lead and copper and discontinue water quality parameter
monitoring in accordance with Sec.  141.87(b), (c) or (d) (as
appropriate) after it demonstrates through subsequent rounds of
monitoring that it meets the criteria of either paragraph (d)(4)(iii)
or (d)(4)(v) of this section.
    (B)(1) Any water system subject to the reduced triennial monitoring
frequency that fails to meet the lead or copper action level during any
four-month monitoring period or fails to operate at or above the
minimum value or within the range of values for the water quality
parameters specified by the State under Sec.  141.82(f) for more than
nine days in any 6-month monitoring period specified in Sec.  141.87(d)
shall conduct tap water monitoring for lead and copper at the frequency
specified in paragraph (d)(3)(i) of this section, collect the number of
samples specified for standard monitoring under paragraph (c) of this
section, and shall resume sampling for water quality parameters in
accordance with Sec.  141.87(d). This standard tap water monitoring
shall begin no later than the 6-month period beginning January 1 of the
calendar year following the lead action level exceedance or water
quality parameter excursion. Such a system may resume reduced
monitoring for lead and copper at the tap and for water quality
parameters within the distribution system under the following
conditions:
    (i) The system may resume annual monitoring for lead and copper
after it has completed two subsequent 6-month rounds of monitoring that
meet the criteria of paragraph (d)(4)(ii)(A) of this section and the
system has received written approval from the State that it is
appropriate to resume reduced monitoring on an annual frequency. This
monitoring shall begin during the calendar year immediately following
the end of the second consecutive 6-month monitoring period.
    (ii) The system may resume triennial monitoring for lead and copper
at the tap at the reduced number of sites after it demonstrates through
subsequent rounds of monitoring that it meets the criteria of either
paragraph (d)(4)(iii) or (d)(4)(v) of this section and the system has
received written approval from the State that it is appropriate to
resume triennial monitoring.
    (iii) The system may reduce the number of water quality parameter
tap water samples required in accordance with Sec.  141.87(e)(1) and
the frequency with which it collects such samples in accordance with
Sec.  141.87(e)(2). Such a system may not resume triennial monitoring
for water quality parameters at the tap until it demonstrates, in
accordance with the requirements of Sec.  141.87(e)(2), that it has re-
qualified for triennial monitoring.
    (2) Any water system subject to the reduced annual monitoring
frequency that fails to meet the lead or copper action level during any
four-month monitoring period or fails to operate at or above the
minimum value or within the range of values for the water quality
parameters specified by the State under Sec.  141.82(f) for more than
nine days in any 6-month monitoring period specified in Sec.  141.87(d)
shall conduct tap water monitoring for lead and copper at the frequency
specified in paragraph (d)(3)(i) of this section, and shall resume
sampling for water quality parameters in accordance with Sec.
141.87(d). This standard monitoring shall begin no later than the 6-
month period beginning January 1 of the calendar year following the
lead action level exceedance or water quality parameter excursion. Such
a system may resume reduced monitoring for lead and copper at the tap
and for water quality parameters within the distribution system under
the following conditions:
    (i) The system may resume annual monitoring for lead and copper
after it has completed two subsequent 6-month rounds of monitoring that
meet the criteria of paragraph (d)(4)(ii)(A) of this section and the
system has received written approval from the State that it is
appropriate to resume reduced monitoring on an annual frequency.

This sampling shall begin during the calendar year immediately
following the end of the second consecutive 6-month monitoring period.
    (ii) The system may resume triennial monitoring for lead and copper
at the tap at the reduced number of sites after it demonstrates through
subsequent rounds of monitoring that it meets the criteria of either
paragraph (d)(4)(iii) or (d)(4)(v) of this section and the system has
received written approval from the State that it is appropriate to
resume triennial monitoring.
    (iii) The system may reduce the number of water quality parameter
tap water samples required in accordance with Sec.  141.87(e)(1) and
the frequency with which it collects such samples in accordance with
Sec.  141.87(e)(2). Such a system may not resume triennial monitoring
for water quality parameters at the tap until it demonstrates, in
accordance with the requirements of Sec.  141.87(e)(2), that it has
qualified for triennial monitoring.
    (3) Any water system subject to the reduced triennial monitoring
frequency that exceeds the lead trigger level during any four-month
monitoring period shall conduct tap water sampling for lead and copper
at the frequency specified in paragraph (d)(4)(ii)(B) of this section,
collect the number of samples specified for standard monitoring under
paragraph (c) of this section, and shall resume sampling for water
quality parameters in accordance with Sec.  141.87(d). This standard
tap water monitoring shall begin no later than the 6-month period
beginning January 1 of the calendar year following the lead trigger
level exceedance or water quality parameter excursion. Such a system
may resume reduced monitoring for lead and copper at the tap and for
water quality parameters within the distribution system under the
following conditions:
    (i) The system may resume triennial monitoring for lead and copper
at the tap at the reduced number of sites after it demonstrates through
subsequent rounds of monitoring that it meets the criteria of either
paragraph (d)(4)(iii) or (d)(4)(v) of this section and the system has
received written approval from the State that it is appropriate to
resume triennial monitoring.
    (ii) The system may reduce the number of water quality parameter
tap water samples required in accordance with Sec.  141.87(e)(1) and
the frequency with which it collects such samples in accordance with
Sec.  141.87(e)(2). Such a system may not resume triennial monitoring
for water quality parameters at the tap until it demonstrates, in
accordance with the requirements of Sec.  141.87(e)(2), that it has re-
qualified for triennial monitoring.
    (iii) Any water system subject to a reduced monitoring frequency
under paragraph (d)(4) of this section shall notify the State in
writing in accordance with Sec.  141.90(a)(3) of any upcoming long-term
change in treatment or addition of a new source as described in that
section. The State must review and approve the addition of a new source
or long-term change in water treatment before it is implemented by the
water system. The State may require the system to resume sampling in
accordance with paragraph (d)(3) of this section and collect the number
of samples specified for standard monitoring under paragraph (c) of
this section or take other appropriate steps such as increased water
quality parameter monitoring, or re-evaluation of corrosion control
treatment given the potentially different water quality considerations.
    (e) Additional monitoring by systems. The results of any monitoring
conducted in addition to the minimum requirements of this section (such
as customer-requested sampling) shall be considered by the system and
the State in making any determinations (i.e., calculating the 90th
percentile lead or copper level) under this subpart. Lead service line
water systems that are unable to collect the minimum number of samples
from Tier 1 or Tier 2 sites shall calculate the 90th percentile using
data from all the lead service lines sites and the highest values from
lower tier sites to meet the specified minimum number of sites. Data
from additional lower tier sites shall be submitted to the State but
shall not be used in the 90th percentile calculation. Customer-
requested samples from known lead service line sites shall be included
in the 90th percentile calculation when they meet the requirements of
paragraph (b) of this section.
    (f) Invalidation of lead and copper tap samples collected under
Sec.  141.86(d). * * *
* * * * *
    (h) Follow-up samples for ``find-and-fix'' under Sec.  141.82(j).
Systems shall collect a follow-up sample at any site that exceeds the
action level within 30 days of receiving the sample results. These
follow-up samples may use different sample volumes or different sample
collection procedures to assess the source of elevated lead. Samples
collected under this section shall be submitted to the State but shall
not be included in the 90th percentile calculation.
    (i) Public availability of tap monitoring results used in the 90th
percentile calculation. All water systems shall make available to the
public the results of the tap water monitoring used to make the 90th
percentile calculation under Sec.  141.80(c)(4). Water systems shall
not be required to list the addresses of the sites where the tap
samples were collected. Large systems shall make available the
monitoring results in a digital format. Small and medium-size systems
shall make available the monitoring results in either a written or
digital format.
* * * * *
0
11. Revise Sec.  141.87 to read as follows:

Sec.  141.87  Monitoring requirements for water quality parameters.

    All large water systems, and all small- and medium-size water
systems that exceed the lead or copper action level, and all small- and
medium-size water systems with corrosion control treatment that exceed
the lead trigger level shall monitor water quality parameters in
addition to lead and copper in accordance with this section. The
requirements of this section are summarized in the table at the end of
this section.
    (a) General requirements. (1) Sample collection methods. (i) Tap
samples shall be representative of water quality throughout the
distribution system, taking into account the number of persons served,
the different sources of water, the different treatment methods
employed by the system, and seasonal variability. Tap sampling under
this section is not required to be conducted at taps targeted for lead
and copper sampling under Sec.  141.86(a).
    Note to paragraph (a)(1)(i): Systems may find it convenient to
conduct tap sampling for water quality parameters at sites used for
coliform sampling under Sec.  141.21 in this chapter.
    (ii) Samples collected at the entry point(s) to the distribution
system shall be from locations representative of each source after
treatment. If a system draws water from more than one source and the
sources are combined before distribution, the system must sample at an
entry point to the distribution system during periods of normal
operating conditions (i.e., when water is representative of all sources
being used).
    (2) Number of samples. (i) Systems shall collect two tap samples
for applicable water quality parameters during each monitoring period
specified under paragraphs (b) through (e) of this section from the
following minimum number of sites. Systems that add sites as a result
of the ``find-and-fix'' requirements in Sec.  141.82(j) shall collect
tap samples for applicable water quality

parameters during each monitoring period under paragraphs (c) through
(e) of this section and shall sample from that adjusted minimum number
of sites.

                     Table 1 to Paragraph (a)(2)(i)
------------------------------------------------------------------------
                                                          Minimum number
                                                           of sites for
           System size (number people served)              water quality
                                                            parameters
------------------------------------------------------------------------
100,000.................................................              25
10,001-100,000..........................................              10
3,301-10,000............................................               3
501-3,300...............................................               2
101-500.................................................               1
<=100...................................................               1
------------------------------------------------------------------------

    (ii)(A) Except as provided in paragraph (c)(2) of this section,
water systems without corrosion control treatment shall collect two
samples for each applicable water quality parameter at each entry point
to the distribution system during each monitoring period specified in
paragraph (b) of this section. During each monitoring period specified
in paragraphs (c) through (e) of this section, water systems shall
collect one sample for each applicable water quality parameter at each
entry point to the distribution system.
    (B) During each monitoring period specified in paragraphs (b)
through (e) of the section, water systems with corrosion control
treatment shall continue to collect one sample for each applicable
water quality parameter at each entry point to the distribution system
no less frequently than once every two weeks.
    (b) Initial sampling for water systems without corrosion control
treatment. (1) Water systems without corrosion control treatment shall
measure the applicable water quality parameters at the locations
specified below during each 6-month monitoring period specified in
Sec.  141.86(d)(1), during which the water system exceeds the lead or
copper action level, and continue until the water system meets the lead
and copper action levels for two consecutive 6-month monitoring
periods.
    (i) At taps:
    (A) pH;
    (B) Alkalinity;
    (C) Orthophosphate, when an inhibitor containing an orthophosphate
compound is used;
    (D) Silica, when an inhibitor containing a silicate compound is
used;
    (ii) At each entry point to the distribution system all of the
applicable parameters listed in paragraph (b)(1) of this section.
    (2) All large water systems shall measure the applicable water
quality parameters as specified in paragraph (b)(1) of this section, at
taps and at each entry point to the distribution system during each 6-
month monitoring period specified in Sec.  141.86(d)(1). All small and
medium-size systems with corrosion control shall measure the applicable
water quality parameters at the locations specified below during each
6-month monitoring period specified in Sec.  141.86(d)(1) during which
the system exceeds the lead trigger level or copper action level.
    (i) At taps:
    (A) pH;
    (B) Alkalinity;
    (C) Orthophosphate, when an inhibitor containing an orthophosphate
compound is used;
    (D) Silica, when an inhibitor containing a silicate compound is
used;
    (ii) At each entry point to the distribution system, all of the
applicable parameters listed in paragraph (b)(2) of this section.
    (c) Monitoring after installation of optimal corrosion control or
re-optimized corrosion control treatment. (1) Any large water system
that re-optimizes corrosion control treatment pursuant to Sec.
141.81(d)(5)(i) and any small or medium-size water system that exceeds
the lead or copper action level and re-optimizes corrosion control
treatment pursuant to Sec.  141.81(d)(5)(ii) shall measure the water
quality parameters at the locations and frequencies specified in
paragraph (c)(1)(i) of this section, during each 6-month monitoring
period specified in Sec.  141.86(d)(2)(i). Any small or medium-size
system which installs optimal corrosion control treatment shall conduct
such monitoring during each 6-month monitoring period specified in
Sec.  141.86(d)(2)(i).
    (i) At taps, two samples for:
    (A) pH;
    (B) Alkalinity;
    (C) Orthophosphate, when an inhibitor containing an orthophosphate
compound is used;
    (D) Silica, when an inhibitor containing a silicate compound is
used;
    (ii) Except as provided in paragraph (c)(3) of this section, at
each entry point to the distribution system, at least one sample no
less frequently than every two weeks (biweekly) for:
    (A) pH;
    (B) When alkalinity is adjusted as part of optimal corrosion
control, a reading of the dosage rate of the chemical used to adjust
alkalinity, and the alkalinity concentration; and
    (C) When a corrosion inhibitor is used as part of optimal corrosion
control, a reading of the dosage rate of the inhibitor used, and the
concentration of orthophosphate or silica (whichever is applicable).
    (iii) Any groundwater system can limit entry point sampling
described in paragraph (c)(2) of this section to those entry points
that are representative of water quality and treatment conditions
throughout the system. If water from untreated groundwater sources
mixes with water from treated groundwater sources, the system must
monitor for water quality parameters both at representative entry
points receiving treatment and representative entry points receiving no
treatment. Prior to the start of any monitoring under this paragraph,
the water system shall provide to the State, written information
identifying the selected entry points and documentation, including
information on seasonal variability, sufficient to demonstrate that the
sites are representative of water quality and treatment conditions
throughout the system.
    (2) States have the discretion to require small and medium-size
systems that exceed the lead trigger level but not the lead and copper
action levels to conduct water quality parameter monitoring as
described in paragraph (c)(ii) of this section or the State can develop
its own water quality control parameter monitoring structure for these
systems.
    (d) Monitoring after State specifies water quality parameter values
for optimal corrosion control. (1) After the State specifies the values
for applicable water quality parameters reflecting optimal corrosion
control treatment under Sec.  141.87(f), all large systems shall
measure the applicable water quality parameters in accordance with
paragraph (c) of this section and determine compliance with the
requirements of Sec.  141.82(g) every six months with the first 6-month
period to begin on either January 1 or July 1, whichever comes first,
after the State specifies the optimal values under Sec.  141.82(f). Any
small or medium-size water system that exceeded an action level shall
conduct such monitoring until the water system meets the lead and
copper action levels and the optimal water quality control parameters
in two consecutive 6-month monitoring periods under Sec.
141.86(d)(3)(i) and this paragraph. For any such small and medium-size
system that is subject to a reduced monitoring frequency pursuant to
Sec.  141.86(d)(4) at the time of the action level exceedance, the
start of the applicable 6-month monitoring period under this paragraph
shall coincide with the start of the applicable monitoring period under
Sec.  141.86(d)(4). Compliance with State-

designated optimal water quality parameter values shall be determined
as specified under Sec.  141.82(g).
    (2) Any small or medium-size system that exceeds the lead trigger
level, but not the lead and copper action levels for which the State
has set optimal water quality control parameters shall monitor
according to the structure in paragraph (c)(ii) of this section, until
the system no longer exceeds the lead trigger level in three
consecutive annual monitoring periods. States have the discretion to
continue to require these systems to monitor optimal water quality
control parameters.
    (e) Reduced monitoring. (1) Any large water system that maintains
the range of values for the water quality parameters reflecting optimal
corrosion control treatment specified by the State under Sec.
141.82(f) and does not exceed the lead trigger level during each of two
consecutive 6-month monitoring periods under paragraph (d) of this
section shall continue monitoring at the entry point(s) to the
distribution system as specified in paragraph (c)(ii) of this section.
Such system may collect two tap samples for applicable water quality
parameters from the following reduced number of sites during each 6-
month monitoring period.

                       Table 1 to Paragraph (e)(1)
------------------------------------------------------------------------
                                                              Reduced
                                                          minimum number
          System size (number of people served)            of sites for
                                                           water quality
                                                            parameters
------------------------------------------------------------------------
100,000.................................................              10
10,001-100,000..........................................               7
3,301-10,000............................................               3
501-3,300...............................................               2
101-500.................................................               1
<=100...................................................               1
------------------------------------------------------------------------

    (2)(i) Any water system that maintains the range of values for the
water quality parameters reflecting optimal corrosion control treatment
specified by the State under Sec.  141.82(f) and does not exceed the
lead trigger level during three consecutive years of monitoring may
reduce the frequency with which it collects the number of tap samples
for applicable water quality parameters specified in this paragraph
(e)(1) of this section, from every six months to annually. This
sampling begins during the calendar year immediately following the end
of the monitoring period in which the third consecutive year of 6-month
monitoring occurs. Any water system that maintains the range of values
for the water quality parameters reflecting optimal corrosion control
treatment specified by the State under Sec.  141.82(f) and meets the
lead trigger level during three consecutive years of annual monitoring
under this paragraph may reduce the frequency with which it collects
the number of tap samples for applicable water quality parameters
specified in paragraph (e)(1) of this section from annually to every
three years. This sampling begins no later than the third calendar year
following the end of the monitoring period in which the third
consecutive year of monitoring occurs.
    (ii) A water system may reduce the frequency with which it collects
tap samples for applicable water quality parameters specified in
paragraph (e)(1) of this section to every three years if it
demonstrates during two consecutive monitoring periods that its tap
water lead level at the 90th percentile is less than or equal to the
PQL for lead specified in Sec.  141.89(a)(1)(ii), that its tap water
copper level at the 90th percentile is less than or equal to 0.65 mg/L
in Sec.  141.80(c)(3), and that it also has maintained the range of
values for the water quality parameters reflecting optimal corrosion
control treatment specified by the State under Sec.  141.82(f).
Monitoring conducted every three years shall be done no later than
every third calendar year.
    (3) A water system that conducts sampling annually shall collect
these samples evenly throughout the year so as to reflect seasonal
variability.
    (4) Any water system subject to the reduced monitoring frequency
that fails to operate at or above the minimum value or within the range
of values for the water quality parameters specified by the State in
Sec.  141.82(f) for more than nine days in any 6-month period specified
in Sec.  141.82(g) shall resume distribution system tap water sampling
in accordance with the number and frequency requirements in paragraph
(d) of this section. Such a system may resume annual monitoring for
water quality parameters at the tap at the reduced number of sites
specified in paragraph (e)(1) of this section after it has completed
two subsequent consecutive 6-month rounds of monitoring that meet the
criteria of that paragraph and/or may resume triennial monitoring for
water quality parameters at the tap at the reduced number of sites
after it demonstrates through subsequent rounds of monitoring that it
meets the criteria of either paragraph (e)(2)(i) or (e)(2)(ii) of this
section.
    (f) Additional monitoring by systems. The results of any monitoring
conducted in addition to the minimum requirements of this section shall
be considered by the water system and the State in making any
determinations (i.e., determining concentrations of water quality
parameters) under this section or Sec.  141.82.
    (g) Additional sites added from Find-and-Fix. Any water system that
adds water quality parameter sites through the ``find-and-fix''
provisions pursuant to Sec.  141.82(j) shall add those sites to the
minimum number of sites specified under paragraphs (a) through (e) of
this section.
0
12. Amend Sec.  141.88 by:
0
a. Revising paragraphs (a)(1)(i), (b), paragraph (d) introductory text,
paragraph (d)(1) introductory text, paragraph (e)(1) introductory and
paragraph (e)(1)(i);
0
b. Removing and reserving paragraph (e)(1)(ii);
0
c. Revising paragraph (e)(2); and
0
d. Removing and reserving paragraph (e)(2)(ii).
    The revisions read as follows:

Sec.  141.88  Monitoring requirements for lead and copper in source
water.

    (a) * * *
    (1) * * *
    (i) Groundwater systems shall take a minimum of one sample at every
entry point to the distribution system after any application of
treatment or in the distribution system at a point which is
representative of each source after treatment (hereafter called a
sampling point). The system shall take one sample at the same sampling
point unless conditions make another sampling point more representative
of each source or treatment plant.
* * * * *
    (b) Monitoring frequency after system exceeds tap water action
level. Any system which exceeds the lead or copper action level at the
tap for the first time or for the first time after a change in source
or source water treatment required under Sec.  141.83(b)(2) shall
collect one source water sample from each entry point to the
distribution system no later than six months after the end of the
monitoring period during which the lead or copper action level was
exceeded. For monitoring periods that are annual or less frequent, the
end of the monitoring period is September 30 of the calendar year in
which the sampling occurs, or if the State has established an alternate
monitoring period, the last day of that period. If the State determines
that source water treatment is not required under Sec.  141.83(b)(2),
the system is not required to conduct additional source water
monitoring unless directed by the State. A system subject to
discontinued source water monitoring under this paragraph, shall notify
the State in writing

pursuant to Sec.  141.90(a)(3) of the addition of a new source.
    (1) The State may waive additional source water monitoring under
the following conditions:
    (i) The water system has already conducted source water monitoring
following a previous action level exceedance;
    (ii) The State has determined that source water treatment is not
required; and
    (iii) The system has not added any new water sources.
    (2) [Reserved].
* * * * *
    (d) Monitoring frequency after State specifies maximum permissible
source water levels. (1) A system shall monitor at the frequency
specified in paragraphs (d)(1) and (2) of this section, in cases where
the State specifies maximum permissible source water levels under Sec.
141.83(b)(4).
* * * * *
    (e) * * *
    (1) A water system using only groundwater may reduce the monitoring
frequency for lead and copper in source water to once during each nine-
year compliance cycle (as that term is defined in Sec.  141.2) provided
that the samples are collected no later than every ninth calendar year
and if the system meets the following criteria:
    (i) The system demonstrates that finished drinking water entering
the distribution system has been maintained below the maximum
permissible lead and copper concentrations specified by the State in
141.83(b)(4) during at least three consecutive compliance periods under
section (d)(1) of this section.
    (ii) [Reserved].
    (2) A water system using surface water (or a combination of surface
water and groundwater) may reduce the monitoring frequency in paragraph
(d)(1) of this section to once during each 9-year compliance cycle (as
that term is defined in Sec.  141.2 of this chapter) provided that the
samples are collected no later than every ninth calendar year and if
the system meets the following criteria:
    (i) * * *
    (ii) [Reserved].
* * * * *
0
13. Amend Sec.  141.89 by revising paragraph (a) introductory text,
paragraph (a)(1) introductory text and paragraph (a)(1)(iii) to read as
follows:

Sec.  141.89  Analytical methods.

    (a) Analyses for lead, copper, pH, alkalinity, orthophosphate, and
silica shall be conducted in accordance with methods in 141.23(k)(1).
    (1) Analyses for alkalinity, orthophosphate, pH, and silica may be
performed by any person acceptable to the State. Analyses under this
section for lead and copper shall only be conducted by laboratories
that have been certified by EPA or the State. To obtain certification
to conduct analyses for lead and copper, laboratories must:
* * * * *
    (iii) Achieve method detection limit for lead of 0.001 mg/L
according to the procedures in Appendix B of part 136 of this title.
* * * * *
0
14. Revise Sec.  141.90 to read as follows:

Sec.  141.90  Reporting Requirements.

    All water systems shall report all of the following information to
the State in accordance with this section.
    (a) Reporting requirements for tap water monitoring for lead and
copper and for water quality parameter monitoring except for small
systems using the point-of-use compliance flexibility option. (1)
Except as provided in paragraph (a)(1)(viii) of this section, a water
system shall report the information specified in paragraphs (a)(1)(i)
through (ix) of this section, for all tap water samples specified in
Sec.  141.86 and for all water quality parameter samples specified in
Sec.  141.87 within the first 10 days following the end of each
applicable monitoring period specified in Sec. Sec.  141.86 and 141.87
(i.e., every six months, annually, every three years, or every nine
years). For monitoring periods with a duration less than six months,
the end of the monitoring period is the last date samples can be
collected during that period as specified in Sec. Sec.  141.86 and
141.87.
    (i) The results of all tap samples for lead and copper including
the location of each site and the criteria under Sec.  141.86(a)(3)
through (8), and/or (9), under which the site was selected for the
water system's sampling pool;
    (ii) Documentation for each tap water lead or copper sample for
which the water system requests invalidation pursuant to Sec.
141.86(f)(2);
    (iii) For lead service line systems, documentation of sampling
pools with insufficient number of lead service line sites to meet the
minimum number of sites criterion in Sec.  141.86(c).
    (A) Community water systems shall document why the system was
unable to meet the minimum number of sites in Sec.  141.86(c) with
sites meeting the criteria under Sec.  141.86(a)(3) or (4) with the
inventory developed under Sec.  141.84(a).
    (B) Non-transient, non-community water systems shall document why
the system was unable to meet the minimum number of sites in Sec.
141.86(c) with sites meeting the criteria under Sec.  141.86(a)(7) with
the inventory developed under Sec.  141.84(a).
    (iv) The 90th percentile lead and copper concentrations measured
from among all lead and copper tap water samples collected during each
monitoring period (calculated in accordance with Sec.  141.80(c)(4) or
(c)(4)(ii)), unless the State calculates the water system's 90th
percentile lead and copper levels under paragraph (h) of this section;
    (v) The water system shall identify any site which was not sampled
during previous monitoring periods, and include an explanation of why
sampling sites have changed;
    (vi) The results of all tap samples for pH, and where applicable,
alkalinity, orthophosphate, or silica collected under Sec.  141.87(b)
through (e);
    (vii) The results of all samples collected at the entry point(s) to
the distribution system for applicable water quality parameters under
Sec.  141.87(b) through (e);
    (viii) A water system shall report the results of all water quality
parameter samples collected under Sec.  141.87(c) through (f) during
each 6-month monitoring period specified in Sec.  141.87(d) within the
first 10 days following the end of the monitoring period unless the
State has specified a more frequent reporting requirement.
    (ix) A copy of the tap sampling protocol provided to residents or
those sampling, to verify that pre-stagnation flushing, aerator
cleaning or removal and the use of narrow-necked collection bottles
were not included as recommendations.
    (2) For a non-transient non-community water system, or a community
water system meeting the criteria of Sec.  141.85(b)(7), that does not
have enough taps that can provide first-draw samples, the water system
must either:
    (i) Provide written documentation to the State identifying standing
times and locations for enough non-first-draw samples to make up its
sampling pool under Sec.  141.86(b)(5) by the start of the first
applicable monitoring period under Sec.  141.86(d) unless the State has
waived prior State approval of non-first-draw sample sites selected by
the water system pursuant to Sec.  141.86(b)(5); or
    (ii) If the State has waived prior approval of non-first-draw
sample sites selected by the water system, identify, in writing, each
site that did not meet the 6-hour minimum stagnation time and the
length of stagnation time for that particular substitute sample

collected pursuant to Sec.  141.86(b)(5) and include this information
with the lead and copper tap sample results required to be submitted
pursuant to paragraph (a)(1)(i) of this section.
    (3) At a time specified by the State, or if no specific time is
designated by the State, then as early as possible prior to the
addition of a new source or any long-term change in water treatment, a
water system shall submit written documentation to the State describing
the change or addition referred to in Sec.  141.86(d)(4). The State
must review and approve the addition of a new source or long-term
change in treatment before it is implemented by the water system.
Examples of long-term treatment changes include the addition of a new
treatment process or modification of an existing treatment process.
Examples of modifications include switching secondary disinfectants,