USEPA. 2018a. Summary Report on Federalism: Lead and Copper Rule.
USEPA. 2018b. 3Ts for Reducing Lead in Drinking Water in Schools and
Child Care Facilities: A Training, Testing, and Taking Action
Approach (Revised Manual). October 2018. Office of Water. EPA 815-B-
18-007. https://www.epa.gov/ground-water-and-drinking-water/3ts-reducing-lead-drinking-water-toolkit.
USEPA. 2019a. America's children and the environment. EPA-100K19004.
https://www.epa.gov/sites/production/files/2019-10/documents/ace2019-v17s.pdf.
USEPA. 2019b. Review of Dust-Lead Standards and the Definition of
Lead-Based Paint. Federal Register 84(131):32632. July 9, 2019.
Washington, DC: Government Printing Office. https://www.govinfo.gov/content/pkg/FR-2019-07-09/pdf/2019-14024.pdf.
USEPA. 2019c. Learn About Lead and Copper Rule Compliance. Office of
Water. EPA-815-F-19-007 https://www.epa.gov/sites/production/files/2019-10/documents/lcr_data_factsheet_10-9-2019.pdf.
USEPA. 2019d. National Primary Drinking Water Regulations: Proposed
Lead and Copper Rule Revisions. Federal Register 84(219):61684.
November 13, 2019. Washington, DC: Government Printing Office.
USEPA. 2019e. Strategies to Achieve Full Lead Service Line
Replacement. October 2019. Office of Water. EPA 810-R-19-003 https://www.epa.gov/sites/production/files/2019-10/documents/strategies_to_achieve_full_lead_service_line_replacement_10_09_19.pdf
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USEPA. 2019f. Economic Analysis for the Proposed Lead and Copper
Rule Revisions. October 2019. Office of Water. EPA docket ID: EPA-
HQ-OW-2017-0300-0003.
USEPA. 2019g. Economic Analysis Appendices for the Proposed Lead and
Copper Rule Revisions. October 2019. Office of Water. EPA docket ID:
EPA-HQ-OW-2017-0300-0002.
USEPA. 2019h. Lead Service Line Replacement Rate Analysis Workbook.
Unpublished raw data.
USEPA. 2019i. Strategies to Achieve Full Lead Service Line
Replacement.
USEPA, 2019j. Memorandum of Understanding on Reducing Lead in
Drinking Water in Schools and Child Care Facilities. September 2019.
https://www.epa.gov/sites/production/files/2019-10/documents/mou_reducing_lead_in_drinking_water_in_schools_final.pdf.
USEPA. 2020a. Economic Analysis for the Final Lead and Copper Rule
Revisions. December 2020. Office of Water.
USEPA. 2020b. Technologies and Costs for Corrosion Control to Reduce
Lead in Drinking Water. December 2020. Office of Water.
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Final Report: Lead Service Line Replacement A Benefit-to-Cost
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65(218):67249. November 9, 2000. Washington, DC: Government Printing
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Research 12(1):29-34.

List of Subjects

40 CFR Part 141

    Environmental protection, Copper, Indians--lands, Intergovernmental
relations, Lead, Lead service line, National Primary Drinking Water
Regulation, Reporting and recordkeeping requirements, Water supply.

40 CFR Part 142

    Environmental protection, Administrative practice and procedure,
Copper, Indians--lands, Intergovernmental relations, Lead, Lead service
line, National Primary Drinking Water Regulation, Reporting and
recordkeeping requirements, Water supply.

Andrew Wheeler,
Administrator.

    For the reasons stated in the preamble, the Environmental
Protection Agency amends 40 CFR parts 141 and 142 as follows:

PART 141--NATIONAL PRIMARY DRINKING WATER REGULATIONS

0
1. The authority citation for part 141 continues to read as follows:

    Authority:  42 U.S.C. 300f, 300g-1, 300g-2, 300g-3, 300g-4,
300g-5, 300g-6, 300j-4, 300j-9, and 300j-11.

0
2. Amend Sec.  141.2 by:
0
a. Revising the definition of ``Action level'';
0
b. Adding in alphabetical order the definitions of ``Aerator'', ``Child
care facility'', ``Elementary schools'', ``Fifth liter sample'', and
``Find-and-fix'';
0
c. Revising the definition for ``First draw sample'';
0
d. Adding in alphabetical order the definitions of ``Full lead service
line replacement,'' ``Galvanized service line'', and ``Gooseneck,
pigtail, or connector'';
0
e. Revising the definition of ``Lead service line'';

0
f. Adding in alphabetical order the definitions of ``Lead status
unknown service line'' and ``Lead trigger level'';
0
g. Revising the definition of ``Medium-size water system'';
0
h. Adding in alphabetical order the definitions of ``Method detection
limit (MDL)'', ``Partial lead service line replacement'', and ``Pitcher
filter'';
0
i. Removing the definition of ``Point-of-use treatment device (POU)'';
0
j. Adding in alphabetical order the definitions ``Point-of-use
treatment device or point of use device (POU),'' ``Practical
quantitation limit (PQL)'', ``Pre-stagnation flushing'', ``School'',
and ``Secondary school''.
0
k. Removing the definition ``Service line sample''.
    l. Adding in alphabetical order the definitions ``System without
corrosion control treatment'', ``Tap sampling monitoring period'',
``Tap sampling period'', ``Tap sampling protocol'', and ``Wide-mouth
bottles''.
    The revisions and additions read as follows:

Sec.  141.2  Definitions.

* * * * *
    Action level means the concentrations of lead or copper in water as
specified in Sec.  141.80(c) which determines requirements under
subpart I of this part. The action level for lead is 0.015 mg/L and the
action level for copper is 1.3 mg/L.
    Aerator means the device embedded in the water faucet to enhance
air flow with the water stream and to prevent splashing.
* * * * *
    Child care facility means a location that houses a licensed
provider of child care, day care, or early learning services to
children, as determined by the State, local, or tribal licensing
agency.
* * * * *
    Elementary school, for the purposes of subpart I of this part only,
means a school classified as elementary by state and local practice and
composed of any span of grades (including pre-school) not above grade
8.
* * * * *
    Fifth liter sample, for purposes of subpart I of this part, means a
one-liter sample of tap water collected in accordance with Sec.
141.86(b).
* * * * *
    Find-and-fix means the requirements under subpart I of this part
that water systems must perform at every tap sampling site that yielded
a lead result above 15 [mu]g/L.
* * * * *
    First draw sample means the first one-liter sample of tap water
collected in accordance with Sec.  141.86(b)(2).
* * * * *
    Full lead service line replacement means the replacement of a lead
service line (as well as galvanized service lines requiring
replacement), as defined in this section, that results in the entire
length of the service line, regardless of service line ownership,
meeting the Safe Drinking Water Act (SDWA) Section 1417 definition of
lead free applicable at the time of the replacement. A full lead
service line replacement includes a replacement where only one portion
of the service line is lead, such as where a partial lead service line
was previously conducted, as long as, upon completion of the
replacement, the entire service line meets the SDWA Section 1417
definition of lead-free applicable at the time of the replacement.
Galvanized service lines that are or were downstream of a lead service
line must also be replaced for a service line to be a full lead service
line replacement. A lead service line that is left in place in the
ground but remains out-of-service may be full lead service line
replacement where a new non-lead service line is installed for use
instead of the out-of-service lead service line.
* * * * *
    Galvanized service line means iron or steel piping that has been
dipped in zinc to prevent corrosion and rusting.
    Gooseneck, pigtail, or connector is a short section of piping,
typically not exceeding two feet, which can be bent and used for
connections between rigid service piping. For purposes of this subpart,
lead goosenecks, pigtails, and connectors are not considered to be part
of the lead service line but may be required to be replaced pursuant to
Sec.  141.84(c).
* * * * *
    Lead service line means a portion of pipe that is made of lead,
which connects the water main to the building inlet. A lead service
line may be owned by the water system, owned by the property owner, or
both. For the purposes of this subpart, a galvanized service line is
considered a lead service line if it ever was or is currently
downstream of any lead service line or service line of unknown
material. If the only lead piping serving the home is a lead gooseneck,
pigtail, or connector, and it is not a galvanized service line that is
considered a lead service line the service line is not a lead service
line. For purposes of Sec.  141.86(a) only, a galvanized service line
is not considered a lead service line.
    Lead status unknown service line means a service line that has not
been demonstrated to meet or not meet the SDWA Section 1417 definition
of lead free. It is not necessary to physically verify the material
composition (for example, copper or plastic) of a service line for its
lead status to be identified (e.g., records demonstrating the service
line was installed after a municipal, State, or Federal lead ban).
    Lead trigger level means a particular concentration of lead in
water that prompts certain activities under subpart I of this part. The
trigger level for lead is a concentration of 10 [mu]g/L.
* * * * *
    Medium-size water system, for the purpose of subpart I of this part
only, means a water system that serves greater than 10,000 persons and
less than or equal to 50,000 persons.
* * * * *
    Method detection limit (MDL) means the minimum concentration of a
substance that can be measured and reported with 99 percent confidence
that the analyte concentration is greater than zero and is determined
from analysis of a sample in a given matrix containing the analyte.
* * * * *
    Partial lead service line replacement means replacement of any
portion of a lead service line or galvanized service line requiring
replacement, as defined in this section, that leaves in service any
length of lead service line or galvanized service line requiring
replacement upon completion of the work. Partial lead service line
replacements are permitted under limited circumstances under Sec.
141.84(d) but do not count towards the mandatory or goal-based lead
service line replacement rate.
* * * * *
    Pitcher filter means a non-plumbed water filtration device which
consists of a gravity fed water filtration cartridge and a filtered
drinking water reservoir that is certified by an American National
Standards Institute accredited certifier to reduce lead in drinking
water.
* * * * *
    Point-of-use treatment device or point of use device (POU) is a
water treatment device physically installed or connected to a single
fixture, outlet, or tap to reduce or remove contaminants in drinking
water. For the purposes of subpart I of this part, it must be certified
by an American National Standards Institute accredited certifier to
reduce lead in drinking water.
    Practical quantitation limit (PQL) means the minimum concentration
of an analyte (substance) that can be

measured with a high degree of confidence that the analyte is present
at or above that concentration.
* * * * *
    Pre-stagnation flushing is the opening of tap(s) to flush standing
water from plumbing prior to the minimum 6-hour stagnation period in
anticipation of lead and copper tap sampling under subpart I of this
part.
* * * * *
    School, for the purpose of subpart I of this part only, means any
building(s) associated with public, private, or charter institutions
that primarily provides teaching and learning for elementary or
secondary students.
* * * * *
    Secondary school, for the purpose of subpart I of this part only,
means a school comprising any span of grades beginning with the next
grade following an elementary or middle school (usually 7, 8, or 9) and
ending with or below grade 12. Both junior high schools and senior high
schools are included.
* * * * *
    System without corrosion control treatment means a public water
system that does not have or purchases all of its water from a system
that does not have:
    (1) An optimal corrosion control treatment approved by the State;
or
    (2) Any pH adjustment, alkalinity adjustment, and/or corrosion
inhibitor addition resulting from other water quality adjustments as
part of its treatment train infrastructure.
    Tap sampling monitoring period, for the purposes of subpart I of
this part, means the period of time during which each water system must
conduct tap sampling for lead and copper analysis. A tap sampling
monitoring period is determined by lead and copper concentrations in
tap samples and the frequency can range from every six months (i.e.,
semi-annual) up to once every nine years. Water systems on semi-annual
tap sampling monitoring must collect samples no less frequently than
every six months while those on annual monitoring must sample no less
frequently than every year. Water systems on triennial monitoring must
collect samples no less frequently than every three years; and those on
monitoring waivers must sample no less frequently than every nine
years. The start of each new tap sampling monitoring period, with the
exception of semi-annual monitoring, must begin on January 1.
    Tap sampling period, for the purpose of subpart I of this part
only, means the time period, within a tap sampling monitoring period,
during which the water system is required to collect samples for lead
and copper analysis. For systems monitoring at a reduced frequency, the
tap sampling period must be between the months of June and September,
unless a different 4-month period of time is approved in writing to be
more appropriate by the State.
    Tap sampling protocol means the instructions given to residents or
those sampling on behalf of the water system to conduct tap sampling
under subpart I of this part.
* * * * *
    Wide-mouth bottles, for the purpose of subpart I of this part only,
means bottles configured with a mouth that is at least 55 mm wide that
are one liter in size.

0
3. Amend Sec.  141.28 by revising paragraph (a) to read as follows:

Sec.  141.28  Certified laboratories.

    (a) For the purpose of determining compliance with Sec.  141.21
through 141.27, 141.30, 141.40, 141.74, 141.89 and 141.402, samples may
be considered only if they have been analyzed by a laboratory certified
by the State except that measurements of alkalinity, disinfectant
residual, orthophosphate, pH, silica, temperature, and turbidity may be
performed by any person acceptable to the State.
* * * * *

0
4. Amend Sec.  141.31 by revising paragraph (d) to read as follows:

Sec.  141.31  Reporting requirements.

* * * * *
    (d)(1) The public water system, within 10 days of completing the
public notification requirements under subpart Q of this part for the
initial public notice and any repeat notices, must submit to the
primary agency a certification that it has fully complied with the
public notification regulations. For Tier 2 and 3 notices, the public
water system must include with this certification a representative copy
of each type of notice distributed, published, posted, and made
available to the persons served by the system and to the media.
    (2) For Tier 1 notices for a lead action level exceedance, public
water systems must provide a copy of any Tier 1 notice to the
Administrator and the head of the primacy agency as soon as
practicable, but not later than 24 hours after the public water system
learns of the violation or exceedance.
* * * * *

0
5. Amend Sec.  141.80 by:
0
a. Revising paragraphs (a), (b), (c), and (d)(1);
0
b. Adding paragraphs (d)(3) and (4);
0
c. Revising paragraphs (e), (f), (g), and (k); and
0
d. Adding paragraph (l).
    The revisions and additions read as follows:

Sec.  141.80  General requirements.

    (a) Applicability, effective date, and compliance deadlines. The
requirements of this subpart constitute the national primary drinking
water regulations for lead and copper.
    (1) The provisions of this subpart apply to community water systems
and non-transient, non-community water systems (in this subpart
referred to as ``water systems'' or ``systems'') as defined at Sec.
141.2.
    (2) The requirements of this subpart are effective as of March 16,
2021.
    (3) Community water systems and non-transient, non-community water
systems must comply with the requirements of this subpart no later than
January 16, 2024, except where otherwise specified at Sec. Sec.
141.81, 141.84, 141.85, 141.86, and 141.90, or where an exemption in
accordance with 40 CFR part 142, subpart C or F, has been established
by the Administrator.
    (4)(i) Between March 16, 2021 and January 16, 2024, community water
systems and non-transient, non-community water systems must comply with
40 CFR 141.80 through 141.91, as codified on July 1, 2020.
    (ii) If an exemption from subpart I of this part has been issued in
accordance with 40 CFR part 142, subpart C or F, prior to March 16,
2021, then the water systems must comply with 40 CFR 141.80 through
141.91, as codified on July 1, 2020, until the expiration of that
exemption.
    (b) Scope. The regulations in this subpart establish a treatment
technique that includes requirements for corrosion control treatment,
source water treatment, lead service line inventory, lead service line
replacement, public notice, monitoring for lead in schools and child
care facilities, and public education. Several of the requirements in
this subpart are prompted by the lead and copper action levels or the
lead trigger level, specified in paragraph (c) of this section, as
measured in samples collected at consumers' taps. The requirements for
sampling for lead in schools and child care facilities and public
education requirements in this subpart apply to all community water
systems regardless of the results of the compliance tap sampling.
    (c) Lead trigger level, lead action level, and copper action level.
Trigger levels and action levels must be determined based on tap water
samples collected in accordance with the tap sampling

monitoring requirements of Sec.  141.86 for the purpose of calculating
the 90th percentile and tested using the analytical methods specified
in Sec.  141.89. The trigger level and action levels described in this
paragraph (c) are applicable to all sections of subpart I of this part.
Trigger level and action levels for lead and copper are as follows:
    (1) The lead trigger level is exceeded if the 90th percentile
concentration of lead as specified in paragraph (c)(4) of this section
is greater than 10 [mu]g/L.
    (2) The lead action level is exceeded if the 90th percentile
concentration of lead as specified in paragraph (c)(4) of this section
is greater than 15 [mu]g/L.
    (3) The copper action level is exceeded if the 90th percentile
concentration of copper as specified in paragraph (c)(4) of this
section is greater than 1.3 mg/L.
    (4) For purposes of this subpart, the 90th percentile concentration
shall be computed as follows:
    (i) For systems that do not have lead service line sites and only
have sites identified as Tier 3, 4, or 5 under Sec.  141.86(a).
    (A) The results of all lead or copper samples taken during a tap
sampling period shall be placed in ascending order from the sample with
the lowest concentration to the sample with the highest concentration.
Each sampling result shall be assigned a number, ascending by single
integers beginning with the number 1 for the sample with the lowest
contaminant level. The number assigned to the sample with the highest
contaminant level shall be equal to the total number of samples taken.
    (B) The number of samples taken during the tap sampling period
shall be multiplied by 0.9.
    (C) The contaminant concentration in the numbered sample yielded by
the calculation in paragraph (c)(4)(i)(B) of this section is the 90th
percentile concentration.
    (D) For water systems serving fewer than 100 people that collect 5
samples per tap sampling period, the 90th percentile concentration is
the average of the highest and second highest concentration.
    (E) For a public water system that has been allowed by the State to
collect fewer than five samples in accordance with Sec.  141.86(c), or
has failed to collect five samples, the sample result with the highest
concentration is considered the 90th percentile value.
    (ii) For public water systems with lead service lines with sites
identified as Tier 1 or 2 under Sec.  141.86(a) with enough Tier 1 or 2
sites to meet the minimum number of sites listed in Sec.  141.86(c):
    (A) The results of all lead or copper samples taken at Tier 1 or
Tier 2 sites during a tap sampling period shall be placed in ascending
order from the sample with the lowest concentration to the sample with
the highest concentration. Sample results from Tier 3, 4, or 5 sites
shall not be included in this calculation. Each sampling result shall
be assigned a number, ascending by single integers beginning with the
number 1 for the sample with the lowest contaminant level. The number
assigned to the sample with the highest contaminant level shall be
equal to the total number of samples taken.
    (B) The number of samples taken at Tier 1 or Tier 2 sites during
the tap sampling period shall be multiplied by 0.9.
    (C) The contaminant concentration in the numbered sample yielded by
the calculation in paragraph (c)(4)(ii)(B) of this section is the 90th
percentile concentration.
    (D) For water systems serving fewer than 100 people that collect 5
samples per tap sampling period, the 90th percentile concentration is
the average of the highest and second highest concentration.
    (E) For a public water system that has been allowed by the State to
collect fewer than five samples in accordance with Sec.  141.86(c), or
has failed to collect five samples, the sample result with the highest
concentration is considered the 90th percentile value.
    (iii) For systems with lead service lines with sites identified as
Tier 1 or 2 under Sec.  141.86(a) with insufficient number of Tier 1 or
2 sites to meet the minimum number of sites listed in Sec.  141.86(c):
    (A) The results of all lead or copper samples taken at Tier 1 or
Tier 2 sites along with the highest results from Tier 3, 4, or 5 sites
sufficient to meet the minimum number of sites shall be placed in
ascending order from the sample with the lowest concentration to the
sample with the highest concentration. Sample results from any
remaining Tier 3, 4, and 5 sites shall not be included in this
calculation. Each sampling result shall be assigned a number, ascending
by single integers beginning with the number 1 for the sample with the
lowest contaminant level. The number assigned to the sample with the
highest contaminant level shall be equal to the total minimum number of
sites listed in Sec.  141.86(c).
    (B) The required minimum number of sites listed in Sec.  141.86(c)
shall be multiplied by 0.9.
    (C) The contaminant concentration in the numbered sample yielded by
the calculation in paragraph (c)(4)(iii)(B) is the 90th percentile
concentration.
    (D) For water systems serving fewer than 100 people that collect 5
samples per tap sampling period, the 90th percentile concentration is
the average of the highest and second highest concentration.
    (E) For a public water system that has been allowed by the State to
collect fewer than five samples in accordance with Sec.  141.86(c), or
has failed to collect five samples, the sample result with the highest
concentration is considered the 90th percentile value.
    (d) Corrosion control requirements. (1) All water systems shall
install and operate corrosion control treatment in accordance with
Sec. Sec.  141.81 and 141.82, and that meets the definition of optimal
corrosion control treatment at Sec.  141.2.
* * * * *
    (3) Any small or non-transient non-community water system that
complies with the applicable small system compliance flexibility
requirements specified by the State under Sec. Sec.  141.81(a)(3) and
141.93 is deemed to be in compliance with the treatment requirement in
paragraph (d)(1) of this section.
    (4) Any water system shall notify the State in writing pursuant to
Sec.  141.90(a)(3) of any upcoming long-term change in treatment or
addition of a new source as described in Sec.  141.90(a)(3). 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 any such water system to conduct additional
monitoring or to take other action the State deems appropriate to
ensure that such water system maintains minimal levels of corrosion
control in its distribution system.
    (e) Source water requirements. (1) Any system exceeding the lead or
copper action level shall implement all applicable source water
treatment requirements specified by the State under Sec.  141.83.
    (2) Any system that changes their source water or makes long-term
treatment changes shall submit written documentation to the State
describing the change in accordance with Sec. Sec.  141.81(a)(3),
141.86(d)(2)(iv), and 141.90(a)(3). The State must review and approve
the change before it is implemented by the water system.
    (f) Lead service line replacements and inventory. Lead service line
replacements must be conducted as follows:
    (1) Any water system exceeding the lead action level specified at
paragraph

(c) of this section must complete mandatory lead service line
replacement. Lead service line replacement must be conducted in
accordance with Sec.  141.84(g) and must include public education
pursuant to Sec.  141.85(a) and (b).
    (2) Any water system exceeding the lead trigger level specified at
paragraph (c) of this section must complete goal-based lead service
line replacement pursuant to Sec.  141.84(f) and public education
pursuant to Sec.  141.85(g) and (h).
    (3) All water systems must prepare an inventory of service lines
connected to its distribution system, whether or not they are owned or
controlled by the water system, to identify those service lines that
are made of lead or of unknown material. The inventory must be prepared
in accordance with Sec.  141.84(a).
    (g) Public education and notification requirements. Pursuant to
Sec.  141.85(d), all water systems must provide notification of lead
tap water monitoring results to persons served at the sites (taps) that
are tested. All community water systems must conduct annual outreach to
local and State health agencies pursuant to Sec.  141.85(i). In
addition:
    (1) Any water system exceeding the lead action level specified at
paragraph (c) of this section shall implement the public education
requirements in accordance with Sec.  141.85(a) and (b).
    (2) Any water system exceeding the lead trigger level specified at
paragraph (c) of this section shall provide notification to all
customers with a lead service line in accordance with Sec.  141.85(g).
    (3) Any water system exceeding the lead action level specified at
paragraph (c) of this section shall notify the public in accordance
with the public notification requirements in subpart Q of this part.
    (4) Any water system with lead service lines, galvanized requiring
replacement or lead status unknown service lines in their inventory as
specified in Sec.  141.84(a) shall inform all consumers with a lead
service line, galvanized requiring replacement, or a lead status
unknown service line in accordance with Sec.  141.85(e).
    (5) Any water system that fails to reach its goal lead service line
replacement rate as required under Sec.  141.84(f) shall conduct
outreach activities in accordance with Sec.  141.85(h).
* * * * *
    (k) Violation of national primary drinking water regulations.
Failure to comply with the applicable requirements of this section and
Sec. Sec.  141.81 through 141.93, including requirements established by
the State pursuant to the provisions in this subpart, is a violation of
the national primary drinking water regulations for lead and copper.
    (l) Testing in schools and child care facilities. All community
water systems must collect samples from all schools and child care
facilities within its distribution system in accordance with Sec.
141.92.

0
6. Revise Sec.  141.81 to read as follows:

Sec.  141.81  Applicability of corrosion control treatment steps to
small, medium, and large water systems.

    (a) Corrosion control treatment. This section sets forth when a
system must complete the corrosion control treatment steps for systems
in paragraph (d) or (e) of this section to optimize or re-optimize
corrosion control treatment based on size, whether the system has
corrosion control treatment, and whether it has exceeded the lead
trigger and/or action level and/or the copper action level.
    (1) Large water system (serving 50,000 people). (i)
Large water systems with corrosion control treatment that exceed either
the lead trigger level or copper action level shall complete the
corrosion control treatment steps specified in paragraph (d) of this
section.
    (ii) Large water systems without corrosion control treatment with
90th percentile results as calculated in accordance with Sec.
141.80(c)(4) that exceed either the lead practical quantitation level
of 0.005 mg/L or the copper action level shall complete the corrosion
control treatment steps specified in paragraph (e) of this section.
    (iii) Large water systems with corrosion control treatment with
90th percentile results as calculated in accordance with Sec.
141.80(c)(4) that exceed the lead practical quantitation level but do
not exceed lead trigger level or the copper action level may be
required by the State to complete the corrosion control treatment steps
in paragraph (d) of this section.
    (2) Medium-size water systems (serving 10,000 and
<=50,000 people). (i) Medium-size water systems with corrosion control
treatment that exceed either the lead trigger level or copper action
level shall complete the corrosion control treatment steps specified in
paragraph (d) of this section.
    (ii) Medium-size water systems without corrosion control treatment
that exceed either the lead or copper action level shall complete the
corrosion control treatment steps specified in paragraph (e) of this
section.
    (iii) Medium-size water systems without corrosion control treatment
that exceed the lead trigger level but do not exceed the lead or copper
action levels shall complete the treatment recommendation step
specified in paragraph (e)(1) of this section (Step 1). The water
system shall complete the remaining steps in paragraph (e) of this
section if it subsequently exceeds either the lead or copper action
level.
    (3) Small water systems (serving <=10,000 people) and non-
transient, non-community water systems. (i) Small and non-transient
non-community water systems with corrosion control treatment that
exceed the lead trigger level or the lead action level but do not
exceed the copper action level, shall complete the corrosion control
treatment steps specified in paragraph (d) of this section, if
corrosion control treatment is approved by the State as a compliance
option under Sec.  141.93(a).
    (ii) Small and non-transient, non-community water systems with
corrosion control treatment that exceed the copper action level shall
complete the corrosion control treatment steps specified in paragraph
(d) of this section.
    (iii) Small and non-transient, non-community water systems without
corrosion control treatment that exceed the lead action level shall
complete the corrosion control treatment steps specified in paragraph
(e) of this section if corrosion control treatment is approved by the
State as a compliance option under Sec.  141.93.
    (iv) Small and non-transient, non-community water systems without
corrosion control treatment that exceed the copper action level shall
complete the corrosion control treatment steps specified in paragraph
(e) of this section.
    (b) Systems deemed to have optimized corrosion control. A system is
deemed to have optimal corrosion control treatment (OCCT) or re-
optimized OCCT if the system satisfies one of the criteria specified in
paragraphs (b)(1) through (3) of this section. Any such system deemed
to have OCCT under this paragraph and which has corrosion control
treatment in place shall continue to operate and maintain that
treatment and meet any additional requirements that the State
determines to be appropriate to ensure optimal corrosion control
treatment is maintained.
    (1) A small or medium-size water system without corrosion control
treatment is deemed to have optimal

corrosion control if the water system does not exceed the lead action
level and copper action level during two consecutive 6-month tap
sampling monitoring periods and thereafter remains at or below the lead
trigger level and copper action level in all tap sampling periods
conducted in accordance with Sec.  141.86.
    (2) A small or medium-size water system with corrosion control
treatment is deemed to have optimal corrosion control treatment if the
water system does not exceed the lead trigger level and copper action
level during two consecutive 6-month monitoring periods conducted in
accordance with Sec.  141.86 and thereafter remains at or below the
lead trigger level and copper action level in all tap sampling periods
conducted in accordance with Sec.  141.86. Small or medium-size systems
with corrosion control treatment that exceed the lead trigger level but
do not exceed the lead and copper action levels during two consecutive
6-month monitoring periods and thereafter remains at or below the lead
and copper action levels in all tap sampling periods conducted in
accordance with Sec.  141.86 are deemed to have re-optimized optimal
corrosion control treatment if the system meets the requirements of
this section. Where the State has set optimal water quality parameters
(OWQPs) under paragraph (d) or (e) of this section a system will not be
eligible to be deemed to have optimized or re-optimized OCCT pursuant
to paragraph (b) of this section.
    (3) Any water system is deemed to have optimized or re-optimized
corrosion control if it submits results of tap water monitoring in
accordance with Sec.  141.86 demonstrating that the 90th percentile tap
water lead level is less than or equal to the lead practical
quantitation level of 0.005 mg/L and does not exceed the copper action
level for two consecutive 6-month tap sampling monitoring periods, and
does not have optimal water quality parameters that were set by the
State under paragraph (d) or (e) of this section. Any such system with
90th percentile tap sample results that thereafter exceeds the lead
practical quantitation level or copper action level during any tap
sampling period shall not be eligible to be deemed to have optimized
OCCT in accordance with this paragraph (b)(3) without first completing
the treatment steps specified in paragraph (d) or (e) of this section
    (i) [Reserved]
    (ii) Any water system deemed to have optimized corrosion control in
accordance with this paragraph (b)(3) shall continue monitoring for
lead and copper at the tap no less frequently than once every three
calendar years using the reduced number of sites specified in Sec.
141.86(c) and collecting samples at times and locations specified in
Sec.  141.86(d)(4)(v).
    (iii) through (v) [Reserved]
    (c) Corrosion control steps completion for small and medium-size
water systems without corrosion control treatment. Any small or medium-
sized system without corrosion control treatment required to complete
the corrosion control steps in paragraph (e) of this section due to its
exceedance of the lead or copper action level that does not exceed
either the lead or copper action levels during each of two consecutive
6-month tap sample monitoring periods pursuant to Sec.  141.86 prior to
the start of Step 3 in paragraph (e)(3) of this section or Step 5 in
paragraph (e)(5) of this section may cease completing the steps and is
not required to complete Step 3 or Step 5, respectively, except that
medium-sized systems with lead service lines and small systems with
lead service lines that choose the corrosion control option pursuant to
Sec.  141.93 must complete a corrosion control treatment study under
paragraph (e)(3)(i) of this section. Any system that initiates Step 5
must complete all remaining steps in paragraphs (e)(6) through (8) of
this section and is not permitted to cease the steps. Any system that
ceases the steps either prior to Step 3 or Step 5 and thereafter
exceeds either the lead or copper action level shall not be permitted
to cease the steps a second time and shall complete the applicable
treatment steps beginning with the first treatment step which was not
previously completed in its entirety. The State may require a water
system to repeat treatment steps previously completed by the water
system when the State determines that this is necessary to implement
the treatment requirements of this section. The State must notify the
system in writing of such a determination and explain the basis for its
decision.
    (d) Treatment steps and deadlines for water systems re-optimizing
corrosion control treatment. Except as provided in paragraph (b) of
this section or Sec.  141.93, water systems with corrosion control
treatment shall complete the following corrosion control treatment
steps (described in the referenced portions of Sec. Sec.  141.82,
141.86, and 141.87) by the indicated time periods.
    (1) Step 1. (i) A water system other than those covered in
paragraph (d)(1)(ii) of this section shall recommend re-optimized
optimal corrosion control treatment (Sec.  141.82(c)) within six months
after the end of the tap sampling period during which it exceeds either
the lead trigger level or copper action level. States may approve
modifications of the existing corrosion control treatment without a
study for systems that exceed the lead trigger level, but do not exceed
the lead or copper action level. The State shall specify re-optimized
corrosion control treatment within six months of receiving the
treatment recommendation. The system shall complete modifications to
corrosion control treatment to have re-optimized corrosion control
treatment installed within six months of the State specifying re-
optimized corrosion control treatment.
    (ii) A water system with lead service lines that exceeds the lead
action level must harvest lead pipes from the distribution system and
construct flow-through pipe loops and operate the loops with finished
water within one year after the end of the tap sampling period during
which it exceeds the lead action level. These water systems must
proceed to Step 3 in paragraph (d)(3) of this section and conduct the
corrosion control studies for re-optimization under paragraph (d)(3)(i)
of this section using the pipe loops.
    (2) Step 2. (i) Large water systems shall conduct the corrosion
control studies for re-optimization under paragraph (d)(3) of this
section (Step 3) unless the system is at or below the lead action level
and the State has approved the modification of the existing corrosion
control treatment made under paragraph (d)(3)(i) of this section (Step
1).
    (ii) Within 12 months after the end of the tap sampling period
during which a small or medium-size water system with corrosion control
treatment exceeds the lead trigger level or copper action level, the
State may require the water system to perform corrosion control studies
for re-optimization (Sec.  141.82(c)(2) or (3)). If the State does not
require the system to perform such studies, the State must specify re-
optimized corrosion control treatment (Sec.  141.82(d)(2)) within the
timeframes specified in paragraphs (d)(2)(ii)(A) and (B) of this
section. The State must provide its determination to the system in
writing.
    (A) For medium-size water systems, within 12 months after the end
of the tap sampling period during which such water system exceeds the
lead trigger level or copper action level.
    (B) For small water systems, within 18 months after the end of the
tap sampling period during which such water system exceeds the lead
trigger level or copper action level.

    (3) Step 3. (i) Any water system with lead service lines that
exceeded the lead action level shall complete the corrosion control
treatment studies for re-optimization within 30 months after the end of
the tap sampling period during which it exceeds the lead action level.
    (ii) If the water system is required to perform corrosion control
studies under paragraph (d)(2) of this section (Step 2), the water
system shall complete the studies (Sec.  141.82(c)(2)) within 18 months
after the State requires that such studies be conducted.
    (4) Step 4. (i) The State shall designate re-optimized corrosion
control treatment (Sec.  141.82(d)(3)) within six months after
completion of paragraph (d)(3)(i) of this section (Step 3).
    (ii) If the water system has performed corrosion control studies
under paragraph (d)(2) of this section (Step 2), the State shall
designate re-optimized corrosion control treatment (Sec.  141.82(d)(2)
or (4)) within six months after completion of paragraph (d)(3)(ii) of
this section (Step 3).
    (5) Step 5. (i) Large water systems shall complete modifications to
corrosion control treatment to have re-optimized corrosion control
treatment installed within 12 months after completion of paragraph
(d)(4)(i) of this section (Step 4).
    (ii) Small or medium-size water systems shall install re-optimized
corrosion control treatment (Sec.  141.82(e)(1)) within 12 months after
completion of paragraph (d)(4)(ii) of this section (Step 4).
    (6) Step 6. Water systems must complete follow-up sampling
(Sec. Sec.  141.86(d)(2) and 141.87(c)) within 12 months after
completion of paragraph (d)(5)(i) or (ii) of this section (Step 5).
    (7) Step 7. The State must review the water system's installation
of treatment and designate optimal water quality control parameters
(Sec.  141.82(f)(1)) within six months of completion of paragraph
(d)(6) of this section (Step 6).
    (8) Step 8. The water system must operate in compliance with the
State-designated optimal water quality control parameters (Sec.
141.82(g)) and continue to conduct tap sampling (Sec.  141.86(d)(3) and
water quality parameter monitoring under Sec.  141.87(d)).
    (e) Treatment steps and deadlines for systems without corrosion
control treatment. Except as provided in paragraph (b) of this section
or Sec.  141.93, water systems without corrosion control treatment must
complete the following corrosion control treatment steps (described in
the referenced portions of Sec. Sec.  141.82, 141.86, and 141.87) by
the indicated time periods.
    (1) Step 1. (i) A water system other than those covered in
paragraph (e)(1)(ii) or (iii) of this section must recommend optimal
corrosion control treatment (Sec.  141.82(a)(1), (2), (3), or (4))
within six months after the end of the tap sampling period during which
it exceeds either the lead trigger level or copper action level.
    (ii) A water system with lead service lines that exceeds the lead
action level must harvest lead pipes from the distribution system and
construct flow-through pipe loops and operate the loops with finished
water within one year after the end of the tap sampling period during
which it exceeds the lead action level. These water systems must
proceed to Step 3 in paragraph (e)(3) of this section and conduct the
corrosion control studies for optimization under paragraph (e)(3)(i) of
this section using the pipe loops.
    (iii) Large water systems under paragraph (a)(1)(ii) of this
section must conduct the corrosion control studies for optimization
under paragraph (e)(3) of this section (Step 3).
    (2) Step 2. Within 12 months after the end of the tap sampling
period during which a water system exceeds the lead or copper action
level, if not otherwise required by this rule, the State may require
the water system to perform corrosion control studies (Sec.
141.82(b)(1)). The State must notify the system in writing of this
requirement. If the State does not require the system to perform such
studies, the State must specify optimal corrosion control treatment
(Sec.  141.82(d)(1) or (2)) within the timeframes established in
paragraphs (e)(2)(i) and (ii) of this section. The State must provide
its determination to the system in writing.
    (i) For medium-size water systems, within 18 months after the end
of the tap sampling monitoring period during which such water system
exceeds the lead trigger level or copper action level.
    (ii) For small water systems, within 24 months after the end of the
tap sampling monitoring period during which such water system exceeds
the lead trigger level or copper action level.
    (3) Step 3. (i) Large water systems with or without lead service
line and medium or small systems with lead service lines that exceed
the lead action level shall complete the corrosion control treatment
studies for optimization within 30 months after the end of the tap
sampling period during which it exceeds the lead action level.
    (ii) If the State requires a water system to perform corrosion
control studies under paragraph (e)(2) of this section (Step 2), the
water system must complete the studies (Sec.  141.82(c)(1)) within 18
months after the State notifies the system in writing that such studies
must be conducted.
    (4) Step 4. (i) The State shall designate re-optimized corrosion
control treatment (Sec.  141.82(d)(3)) within six months after
completion of paragraph (d)(3)(i) of this section (Step 3).
    (ii) If the water system has performed corrosion control studies
under paragraph (e)(2) of this section (Step 2), the State must
designate optimal corrosion control treatment (Sec.  141.82(d)(1))
within six months after completion of paragraph (e)(3) of this section
(Step 3).
    (5) Step 5. The water system must install optimal corrosion control
treatment (Sec.  141.82(e)(1)) within 24 months after the State
designates optimal corrosion control treatment under paragraph (e)(2)
or (4) of this section (Step 2 or Step 4).
    (6) Step 6. The water system shall complete follow-up sampling
(Sec. Sec.  141.86(d)(2)(i) and 141.87(c)) within 12 months after
completion of paragraph (e)(5) of this section (Step 5).
    (7) Step 7. The State must review the water system's installation
of treatment and designate optimal water quality control parameters
(Sec.  141.82(f)(1)) within six months of completion of paragraph
(e)(6) of this section (Step 6).
    (8) Step 8. The water system must operate in compliance with the
State-designated optimal water quality control parameters (Sec.
141.82(g)(1)) and continue to conduct tap sampling (Sec.  141.86(d)(3)
and water quality parameter monitoring under Sec.  141.87(d)).
    (f) Treatment steps and deadlines for small community water systems
and non-transient non-community water systems electing corrosion
control treatment (CCT) as a compliance option under Sec.  141.93, or
as required by the State. Water systems selecting the corrosion control
small system compliance flexibility option must complete the following
steps by the indicated time periods.
    (1) Step 1. A water system recommends corrosion control treatment
as a small system compliance flexibility option under Sec.
141.93(a)(2) within six months after the end of the tap sampling period
during which it exceeds either the lead trigger level or the lead
action level.
    (2) Step 2. The State approves in writing the recommendation of
corrosion control treatment as a small system compliance flexibility
option or designates an alternative option in accordance with Sec.
141.93(a) within six months of the recommendation by the water system
in paragraph (f)(1) of this

section (Step 1). Water systems required by the State to optimize or
re-optimize corrosion control treatment must follow the schedules in
paragraph (d) or (e) of this section, beginning with Step 3 in
paragraph (d)(3) or (e)(3) of this section unless the State specifies
optimal corrosion control treatment pursuant to either paragraph
(d)(2)(ii) or (e)(2)(ii) of this section, as applicable.

0
7. Revise Sec.  141.82 to read as follows:

Sec.  141.82  Description of corrosion control treatment requirements.

    This section sets forth the requirements applicable to systems and
states in the designation of optimal corrosion control treatment for a
system that is optimizing or reoptimizing corrosion control treatment.
Each system must complete the corrosion control treatment requirements
in this section as applicable to such system under Sec.  141.81.
    (a) System recommendation regarding corrosion control treatment for
systems that do not contain lead service lines and systems with lead
service lines that do not exceed the lead action level. (1) Any system
under this paragraph (a) without corrosion control treatment that is
required to recommend a treatment option in accordance with Sec.
141.81(e) must, based on the results of lead and copper tap sampling
and water quality parameter monitoring, recommend designation of one or
more of the corrosion control treatments listed in paragraph (c)(1)(i)
of this section. Small community water systems and non-transient non-
community water systems that exceed the copper action level must comply
with this paragraph (a)(1). The State may require the system to conduct
additional water quality parameter monitoring to assist the State in
reviewing the system's recommendation.
    (2) Any small community water system or non-transient non-community
water system in this paragraph (a) without corrosion control treatment
that chooses to pursue a small water system compliance flexibility
option and is required to recommend an option in accordance with Sec.
141.81(f) must, based on the results of lead tap sampling and water
quality parameter monitoring, recommend designation of one of the
options listed in Sec.  141.93. Systems with no lead service lines that
exceed the lead action level and select corrosion control under Sec.
141.93(a)(2) must recommend designation of one or more of the corrosion
control treatments listed in paragraph (c)(1) of this section as the
optimal corrosion control treatment for that system.
    (3) Any system under this paragraph (a) that exceeds the lead
action level and selects corrosion control under Sec.  141.93(a)(2)
must recommend designation of one or more of the corrosion control
treatments listed in paragraph (c)(1)(i) of this section as the optimal
corrosion control treatment for that system. A corrosion control study
under paragraph (c) of this section is not required for medium and
small systems that exceed the lead trigger level but do not exceed the
lead and copper action levels, unless required by the state.
    (4) Any small community water system or non-transient, non-
community water system with corrosion control treatment that that
exceeds the lead action level and selects corrosion control under Sec.
141.93(a)(2) must 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.
    (5) States may waive the requirement for a system to recommend OCCT
if the State requires the system, in writing, to complete a corrosion
control study within 3 months after the end of the tap sampling period
during which the exceedance occurred. Such systems shall proceed
directly to paragraph (c) of this section and complete a corrosion
control study.
    (b) State decision to require studies to identify initial optimal
corrosion control treatment and re-optimized optimal corrosion control
treatment except for large systems and small and medium systems with
lead service lines that exceed the lead action level. Corrosion control
treatment studies are always required for large systems that exceed the
lead action level, large water systems without corrosion control
treatment with 90th percentile results that exceed either the lead
practical quantitation level of 0.005 mg/L or the copper action level,
medium sized systems with lead service lines that exceed the lead
action level, and small systems with lead service lines that exceed the
lead action level and select the corrosion control treatment option
under Sec.  141.93(a).
    (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 but not 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. 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)(2) 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 treatment that are required to conduct
corrosion control studies must complete the following:
    (i) Any water system without corrosion control treatment must
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
corrosion inhibitor residual concentration in all test samples;
    (C) The addition of an orthophosphate-based corrosion inhibitor at
a concentration sufficient to maintain an orthophosphate residual
concentration of 1 mg/L (as PO4) in all test samples; and
    (D) The addition of an orthophosphate-based corrosion inhibitor at
a concentration sufficient to maintain an orthophosphate residual
concentration of 3 mg/L (as PO4) in all test samples.
    (ii) The water system must evaluate each of the corrosion control
treatments using either pipe rig/loop tests, metal coupon tests,
partial-system tests, or analyses based on documented analogous
treatments with other systems of similar size, water chemistry, and
distribution system configurations. Large and medium systems and small
community water systems and non-transient non-community water systems
that select the corrosion control treatment option under Sec.  141.93
with lead service lines that exceed the lead action level must conduct
pipe rig/loop studies using harvested lead service lines from their
distribution systems to assess the effectiveness of corrosion control
treatment options on the existing pipe scale. For these systems,

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 must measure the following water quality
parameters in any tests conducted under this paragraph (c)(1)(iii)
before and after evaluating the corrosion control treatments listed in
paragraphs (c)(1)(i) and (ii) of this section:
    (A) Lead;
    (B) Copper;
    (C) pH;
    (D) Alkalinity;
    (E) Orthophosphate as PO4 (when an orthophosphate-based
inhibitor is used); and
    (F) Silicate (when a silicate-based inhibitor is used).
    (iv) The water system must 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 drinking 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 must 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 drinking water quality treatment processes. Systems using
coupon studies to screen and/or pipe loop/rig studies to evaluate
treatment options must 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 must evaluate the effect of the chemicals used
for corrosion control treatment on other drinking 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 must recommend to the State in writing the
treatment option that the corrosion control studies indicate
constitutes optimal corrosion control treatment for that system as
defined in Sec.  141.2. The water system must 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 corrosion control treatment that are required to
conduct corrosion control studies to determine re-optimized OCCT must
complete the following:
    (i) The water system must evaluate the effectiveness of the
following treatments, and if appropriate, combinations of the following
treatments to identify the re-optimized optimal corrosion control
treatment for the system:
    (A) Alkalinity and/or pH adjustment, or re-adjustment;
    (B) The addition of an orthophosphate- or silicate-based corrosion
inhibitor at a concentration sufficient to maintain an effective
corrosion inhibitor residual concentration in all test samples if no
such inhibitor is utilized;
    (C) The addition of an orthophosphate-based corrosion inhibitor at
a concentration sufficient to maintain an orthophosphate residual
concentration of 1 mg/L (PO4) in all test samples unless the
current inhibitor process already meets this residual; and
    (D) The addition of an orthophosphate-based corrosion inhibitor at
a concentration sufficient to maintain an orthophosphate residual
concentration of 3 mg/L (PO4) in all test samples unless the
current inhibitor process already meets this residual.
    (ii) The water system must evaluate each of the corrosion control
treatments using either pipe rig/loop tests, metal coupon tests,
partial-system tests, or analyses based on documented analogous
treatments with other systems of similar size, water chemistry, and
distribution system configurations. If the water system has lead
service lines and exceeds the lead action level, it must conduct pipe
rig/loop studies using harvested lead service lines from their
distribution systems to assess the effectiveness of corrosion control
treatment options on the existing pipe scale. For these systems, 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 must measure the following water quality
parameters in any tests conducted under this paragraph (c)(2)(iii)
before and after evaluating the corrosion control treatments listed in
paragraphs (c)(2)(i) and (ii) of this section:
    (A) Lead;
    (B) Copper;
    (C) pH;
    (D) Alkalinity;
    (E) Orthophosphate as PO4 (when an orthophosphate-based
inhibitor is used); and
    (F) Silicate (when a silicate-based inhibitor is used).
    (iv) The water system must 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 drinking 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 must 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 drinking 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 must evaluate the effect of the chemicals used
for corrosion control treatment on other drinking 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 must recommend to the State in writing the
treatment option that the corrosion control studies indicate
constitutes optimal corrosion control treatment for that system as
defined in Sec.  141.2. The water system must provide a rationale for
its recommendation along with all supporting documentation specified in
paragraph (c)(1)(i) through (v) of this section.

    (d) State designation of optimized optimal corrosion control
treatment and re-optimized optimal corrosion control treatment. When
designating optimal corrosion control treatment, the State must
consider the effects that additional corrosion control treatment will
have on water quality parameters and on other drinking water quality
treatment processes. The State must notify the water system of its
designation of 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 must provide
the information.
    (1) Designation of OCCT for systems without corrosion control
treatment. Based upon considerations of available information
including, where applicable, studies conducted under paragraph (c)(1)
of this section and/or a system's recommended corrosion control
treatment option, the State must either approve the corrosion control
treatment option recommended by the system or designate alternative
corrosion control treatment(s) from among those listed in paragraph
(c)(1)(i) of this section or, where applicable, an alternate small
water system compliance flexibility option under Sec.  141.93(a).
    (2) Designation of re-optimized OCCT for systems with corrosion
control treatment. Based upon considerations of available information
including, where applicable, studies conducted under paragraph (c)(2)
of this section and/or a system's recommended treatment alternative,
the State must either approve the corrosion control treatment option
recommended by the water system or designate alternative corrosion
control treatment(s) from among those listed in paragraph (c)(2)(i) of
this section or, where applicable, an alternate small water system
compliance flexibility option under Sec.  141.93.
    (e) Installation of optimal corrosion control treatment and re-
optimization of corrosion control treatment. Each system must properly
install and operate throughout its distribution system the optimal
corrosion control treatment designated by the State under paragraph (d)
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. The State must 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 (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 must designate:
    (1) A minimum value or a range of values for pH measured at each
entry point to the distribution system.
    (2) 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.
    (3) If a corrosion inhibitor is used, a minimum concentration or a
range of concentrations for orthophosphate (as PO4) or
silicate measured at each entry point to the distribution system.
    (4) 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 an orthophosphate concentration shall be equal to or greater
than 0.5 mg/L (asPO4) for OCCT designations under paragraph
(d)(1) of this section and 1.0 mg/L for OCCT designations under
paragraph (d)(2) of this section, unless the State determines that
meeting the applicable minimum orthophosphate residual is not
technologically feasible or is not necessary for optimal corrosion
control treatment.
    (5) 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.
    (6) 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 treatment for the water system. The State must 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 optimal corrosion control treatment.
All systems optimizing or re-optimizing corrosion control must 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) of this
section, in accordance with this paragraph (g) 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, and any water system with corrosion control treatment, optimal
corrosion control treatment, or re-optimized OCCT that is not required
to monitor water quality parameters under Sec.  141.87. Compliance with
the requirements of this paragraph (g) 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 (g) for a six-month
period if it has excursions for any State-specified parameter on more
than nine days, cumulatively, 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 set out in paragraphs (g)(1) through (3) of this section.
States have discretion to not include results of obvious sampling
errors from this calculation. Sampling errors must still be recorded
even when not included in calculations.
    (1) On days when more than one measurement for the water quality
parameter is collected at the sampling location, the daily value must
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 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 (g)(1).
    (2) 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.
    (3) 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) of this section, or optimal water quality
control parameters under paragraph (f) 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. A revised
determination must 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 EPA in lieu of the State on optimal
corrosion control treatment and re-optimized corrosion control
treatment. Pursuant to the procedures in Sec.  142.19 of this chapter,
EPA Regional Administrator may review optimal corrosion control
treatment determinations made by a State under paragraph (d)(1) or (2),
(f), or (h) of this section and issue Federal treatment determinations
consistent with the requirements of paragraph (d)(1) or (2), (f), or
(h) of this section where the Regional Administrator finds that:
    (1) A State has failed to issue a treatment determination by the
applicable deadlines contained in Sec.  141.81;
    (2) A State has abused its discretion in a substantial number of
cases or in cases affecting a substantial population; or
    (3) The technical aspects of a State's determination would be
indefensible in a 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: corrosion control treatment assessment. The water
system must 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. Small water systems without
corrosion control treatment may have up to 14 days to collect the
samples. The water system must measure the following parameters:
    (i) pH;
    (ii) Alkalinity;
    (iii) Orthophosphate (as PO4), 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.
    (vi) All water systems required to meet optimal water quality
control parameters but that do not have an existing water quality
parameter location that meets the requirement of this section must add
new sites to the minimum number of sites as described in Sec.
141.87(g). Sites must be added until a system has twice the minimum
number of sites listed in Table 1 to Sec.  141.87(a)(2). When a system
exceeds this upper threshold for the number of sites, the State has
discretion to determine if the newer site can better assess the
effectiveness of the corrosion control treatment and to remove existing
sites during sanitary survey evaluation of OCCT.
    (2) Step 2: Site assessment. 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 must 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 must 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 (j)(3) to determine if either
localized or centralized adjustment of the optimal corrosion control
treatment or other distribution system actions are necessary and submit
the recommendation to the State within six months after the end of the
tap sampling period in which the site(s) exceeded the lead action
level. Corrosion control treatment modification may not be necessary to
address every exceedance. Other distribution system actions may include
flushing to reduce water age. Water systems must note the cause of the
elevated lead level, if known from the site assessment, in their
recommendation to the State as site-specific issues can be an important
factor in why the system is not recommending any adjustment of
corrosion control treatment or other distribution system actions.
Systems in the process of optimizing or re-optimizing optimal corrosion
control treatment under paragraphs (a) through (f) of this section do
not need to submit a treatment recommendation for find-and-fix.
    (4) Step 4. The State shall approve the treatment recommendation or
specify a different approach within six months of completion of Step 3
as described in paragraph (j)(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 must complete modifications to its corrosion
control treatment within 12 months after completion of Step 4 as
described in paragraph (j)(4) of this section. Systems without
corrosion control treatment required to install optimal corrosion
control treatment must follow the schedule in Sec.  141.81(e).
    (6) Step 6. Water systems adjusting its optimal corrosion control
treatment must complete follow-up sampling (Sec. Sec.  141.86(d)(2) and
141.87(c)) within 12 months after completion of Step 5 as described in
paragraph (j)(5) of this section.
    (7) Step 7. For water systems adjusting its optimal corrosion
control treatment, the State must 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 Step 6 as described in paragraph (j)(6) of this section.
    (8) Step 8. For a water system adjusting its optimal corrosion
control treatment, the water system must operate in compliance with the
State-designated optimal water quality control parameters (Sec.
141.82(g)) and continue to conduct tap sampling (Sec. Sec.
141.86(d)(3) and 141.87(d)).

0
8. 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 an
inventory to identify the materials of service lines connected to the
public water distribution system. The inventory must meet the following
requirements:
    (1) All water systems must develop an initial inventory by January
16, 2024,

and submit it to the primacy agency in accordance with Sec.  141.90.
    (2) The 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).
    (3) A water system must use any information on lead and galvanized
iron or steel that it has identified pursuant to Sec.  141.42(d) 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 must also review the sources of information listed in
paragraphs (a)(3)(i) through (iv) of this section to identify service
line materials for the initial inventory. The water system may use
other sources of information not listed in paragraphs (a)(3)(i) through
(iv) of this section if approved by the State.
    (i) All construction and plumbing codes, permits, and existing
records or other documentation which indicates the service line
materials used to connect 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, information, or identification method provided
or required by the State to assess service line materials.
    (4) Each service line, or portion of the service line where
ownership is split, must be categorized in the following manner:
    (i) ``Lead'' where the service line is made of lead.
    (ii) ``Galvanized Requiring Replacement'' where a galvanized
service line is or was at any time downstream of a lead service line or
is currently downstream of a ``Lead Status Unknown'' service line. If
the water system is unable to demonstrate that the galvanized service
line was never downstream of a lead service line, it must presume there
was an upstream lead service line.
    (iii) ``Non-lead'' where the service line is determined through an
evidence-based record, method, or technique not to be lead or
galvanized requiring replacement. The water system may classify the
actual material of the service line (i.e., plastic or copper) as an
alternative to classifying it as ``Non-lead.''
    (iv) ``Lead Status Unknown'' where the service line material is not
known to be lead, galvanized requiring replacement, or a non-lead
service line, such as where there is no documented evidence supporting
material classification. The water system may classify the line as
``Unknown'' as an alternative to classifying it as ``Lead Status
Unknown,'' however, all requirements that apply to ``Lead Status
Unknown'' service lines must also apply to those classified as
``Unknown.'' Water systems may elect to provide more information
regarding their unknown lines as long as the inventory clearly
distinguishes unknown service lines from those where the material has
been verified through records or inspection.
    (5) Water systems shall identify and track service line materials
in the inventory as they are encountered in the course of its normal
operations (e.g., checking service line materials when reading water
meters or performing maintenance activities).
    (6) Water systems must update the inventory based on all applicable
sources described in paragraphs (a)(3) and (5) of this section and any
lead service line replacements or service line material inspections
that may have been conducted. The water system may use other sources of
information if approved by the State and must use other sources of
information provided or required by the State. Water systems must
submit the updated inventory to the State in accordance with Sec.
141.90(e). The inventory updates must be reflected in the publicly
accessible inventory no less frequently than when required to be
submitted to the State.
    (i) Water systems whose inventories contain only non-lead service
lines are not required to provide inventory updates to the State or to
the public. If, in the future, such a water system finds a lead service
line within its system, it must prepare an updated inventory in
accordance with paragraph (a) of this section on a schedule established
by the State.
    (ii) [Reserved]
    (7) To calculate the number of service line replacements applicable
to paragraphs (f) and (g) of this section, the replacement rate must be
applied to the sum of known lead and galvanized requiring replacement
service lines when the system first exceeds the trigger or action level
plus the number of lead status unknown service lines in the beginning
of each year of a system's annual goal or mandatory lead service line
replacement program.
    (i) Each service line shall count only once for purposes of
calculating the required number of service line replacements, even
where the ownership of the service line is split and both the customer-
owned and system-owned portions require replacement.
    (ii) The number of service lines requiring replacement must be
updated annually to subtract the number of lead status unknown service
lines that were discovered to be non-lead and to add the number of non-
lead service lines that were discovered to be a lead or galvanized
requiring replacement service line.
    (iii) Verification of a lead status unknown service line as non-
lead in the inventory does not count as a service line replacement.
    (8) The service line materials inventory must be publicly
accessible.
    (i) The inventory must include a location identifier, such as a
street address, block, intersection, or landmark, associated with each
lead service line and galvanized requiring replacement service line.
Water systems may, but are not required to, include a locational
identifier for lead status unknown service lines or list the exact
address of each service line.
    (ii) Water systems serving greater than 50,000 persons must make
the publicly accessible inventory available online.
    (9) When a water system has no lead, galvanized requiring
replacement, or lead status unknown service lines (regardless of
ownership) in its inventory, it may comply with the requirements in
paragraph (a)(8) of this section using a written statement, in lieu of
the inventory, declaring that the distribution system has no lead
service lines or galvanized requiring replacement service lines. The
statement must include a general description of all applicable sources
described in paragraphs (a)(3), (5), and (6) of this section used to
make this determination.
    (10) Instructions to access the service line inventory (including
inventories consisting only of a statement in accordance with paragraph
(a)(9) of this section) must be included in Consumer Confidence Report
in accordance with Sec.  141.153(d)(4)(xi).
    (b) Lead service line replacement plan. All water systems with one
or more lead, galvanized requiring replacement, or lead status unknown
service lines in their distribution system must, by January 16, 2024,
submit a lead service line replacement plan to the

State in accordance with Sec.  141.90(e). The lead service line
replacement plan must be sufficiently detailed to ensure a system is
able to comply with the lead service line replacement requirements in
accordance with this section. The plan must include a description of:
    (1) A strategy for determining the composition of lead status
unknown service lines in its inventory;
    (2) A procedure for conducting full lead service line replacement;
    (3) A strategy for informing customers before a full or partial
lead service line replacement;
    (4) For systems that serve more than 10,000 persons, a lead service
line replacement goal rate recommended by the system in the event of a
lead trigger level exceedance;
    (5) A procedure for customers to flush service lines and premise
plumbing of particulate lead;
    (6) A lead service line replacement prioritization strategy based
on factors including but not limited to the targeting of known lead
service lines, lead service line replacement for disadvantaged
consumers and populations most sensitive to the effects of lead; and
    (7) A funding strategy for conducting lead service line
replacements which considers ways to accommodate customers that are
unable to pay to replace the portion they own.
    (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 planned or
unplanned 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 (f) and (g) 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 Sec.  141.85(f)(2).
    (6) The requirements of paragraphs (c)(1), (2), (3), and (5) of
this section do not apply if state law includes lead connectors in the
definition of lead service lines, prohibits partial lead service line
replacements, and requires systems to remove all lead service lines
irrespective of a system's 90th percentile lead level.
    (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 affected
service line, or the owner's authorized agent, as well as non-owner
resident(s) served by the affected 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 affected service line not owned by the water system.
    (i) Before the affected service line is returned to service, the
water system must provide notification meeting the content requirements
of Sec.  141.85(a) 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 affected 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 the procedure developed in paragraph (b)(5)
of this section before the affected service line is returned to
service.
    (iii) The water system must provide the consumer with a pitcher
filter or point-of-use device certified by an American National
Standards Institute accredited certifier to reduce lead, six months of
replacement cartridges, and instructions for use before the affected
service line is returned to service. If the affected service line
serves more than one residence or non-residential unit (e.g., a multi-
unit building), the water system must provide a filter, six months of
replacement cartridges and use instructions to every residence in the
building.
    (iv) The water system must offer to collect a follow up tap sample
between three months and six months after completion of any partial
replacement of a lead service line. The water system must provide the
results of the sample 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 persons served by the affected service line
in accordance with paragraphs (d)(1)(i) through (iii) of this section
before the affected service line is returned to service.
    (3) When a water system is notified by the customer that the
customer's portion of the lead service line will be replaced, the water
system must make a good faith effort to coordinate simultaneous
replacement of its portion of the service line. If simultaneous
replacement cannot be conducted, the water system must replace its
portion as soon as practicable but no later than 45 days from the date
the customer replaces its portion of the lead service line. The water
system must provide notification and risk mitigation measure in
accordance with paragraphs (d)(1)(i) through (iii) of this section. If
the water system fails to replace its portion of the lead service line
within 45 days from the date the customer replaces the customer's
portion of the lead service line, the water system must notify the
State within 30 days of failing to meet the deadline in accordance with
Sec.  141.90(e) and complete the replacement no later than 180 days of
the date the customer replaces its portion.
    (4) When a water system is notified or otherwise learns that
replacement of a customer-owned lead service line has occurred within
the previous six months and left in place a system-owned lead service
line, the water system must replace its portion within 45 days from the
day of becoming aware of the customer replacement. The water system
must provide notification and risk mitigation measures in accordance
with paragraphs (d)(1)(i) through (iii) of this section within 24 hours
of becoming aware of the customer replacement. If the water system
fails to replace its portion of the affected service line within 45
days of becoming aware of the customer replacement, it must notify the
State within 30 days of failing to meet the deadline in accordance with
Sec.  141.90(e). The water system must complete the replacement no
later than 180 days after the date the customer replaces its portion.
    (5) When a water system is notified or otherwise learns of a
replacement of a customer-owned lead service line which has occurred
more than six months in the past, the water system is not

required to complete the lead service line replacement of the system-
owned portion under this paragraph (d)(5), however the system-owned
portion must still be included in the calculation of a lead service
line replacement rate under paragraph (a)(7) of this section.
    (e) Requirements for conducting full lead service line replacement.
Any water system that conducts a full lead service line replacement
must provide notice to the owner of the affected service line, or the
owner's authorized agent, as well as non-owner resident(s) served by
the affected service line within 24 hours of completion of the
replacement. 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.
    (1) The notification must meet the content requirements of Sec.
141.85(a) 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.
    (2) The water system must provide information about service line
flushing in accordance with the procedure developed under paragraph
(b)(5) of this section before the replaced service line is returned to
service.
    (3) The water system must provide the consumer with a pitcher
filter or point-of-use device certified by an American National
Standards Institute accredited certifier to reduce lead, six months of
replacement cartridges, and instructions for use before the replaced
service line is returned to service. 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 filter and six months of
replacement cartridges and use instructions to every residence in the
building.
    (4) The water system must offer to the consumer to take a follow up
tap sample between three months and six months after completion of any
full replacement of a lead service line. The water system must provide
the results of the sample to the consumer in accordance with paragraph
(d) of this section.
    (f) Goal-based full lead service line replacement for water systems
whose 90th percentile lead level is above the trigger level but at or
below the lead action level. Water systems that serve more than 10,000
persons 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 full lead service
line replacement at a rate approved by the state.
    (1) The water system must calculate the number of full lead service
line replacements it must conduct annually in accordance with paragraph
(a)(7) of this section.
    (2) Replacement of lead service lines must be conducted in
accordance with the requirements of paragraph (d) or (e) of this
section.
    (3) 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.
    (4) The water system must provide information to customers with
lead, galvanized requiring replacement, or lead status unknown service
lines as required in Sec.  141.85(g).
    (5) Any water system that fails to meet its lead service line
replacement goal must:
    (i) Conduct public outreach activities pursuant to Sec.  141.85(h)
until either the water system meets its replacement goal, or tap
sampling shows the 90th percentile of lead is at or below the trigger
level for two consecutive one-year monitoring periods.
    (ii) Recommence its goal-based lead service line replacement
program pursuant to this paragraph (f)(5)(ii) if the 90th percentile
lead level anytime thereafter exceeds the lead trigger level but is at
or below the lead action level.
    (6) The first year of lead service line replacement shall begin on
the first day following the end of the tap sampling period in which the
lead trigger level was exceeded. If sampling is required annually or
less frequently, the end of the tap sampling 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.
    (g) Mandatory full lead service line replacement for water systems
whose 90th percentile lead level exceeds the lead action level. Water
systems serving more than 10,000 persons that exceed the lead action
level in tap samples taken pursuant to Sec.  141.86 must conduct
mandatory full lead service line replacement at an average annual rate
of at least three percent, calculated on a two-year rolling basis.
    (1) The average annual number of full lead service line
replacements must be calculated in accordance with paragraph (a)(7) of
this section.
    (2) Lead service line replacement must be conducted in accordance
with the requirements of paragraphs (d) and (e) of this section.
    (3) Only full lead service line replacement count towards a water
system's mandatory replacement rate of at least three percent annually.
Partial lead service line replacements do not count towards the
mandatory replacement rate.
    (4) Water systems must provide information to customers with lead,
galvanized requiring replacement, or lead status unknown service lines
consistent with Sec.  141.85(g).
    (5) Community water systems serving 10,000 or fewer persons and
Non-transient non-community water systems for which the state has
approved or designated lead service line replacement as a compliance
option must conduct lead service line replacement as described in Sec.
141.93(a)(1). Replacement of lead service lines must be conducted in
accordance with the requirements of paragraphs (d) and (e) of this
section.
    (6) A water system may cease mandatory lead service line
replacement when it has conducted a cumulative percentage of
replacements greater than or equal to 3%, or other percentage specified
in paragraph (g)(9) of this section, of the service lines specified in
paragraph (a)(7) of this section multiplied by the number of years that
elapsed from when the system most recently began mandatory lead service
line replacement and the date on which the system's 90th percentile
lead level, in accordance with Sec.  141.80(c)(4), has been calculated
to be at or below the lead action level during each of four consecutive
six-month tap sampling monitoring periods. If tap samples collected in
any such system thereafter exceed the lead action level, the system
shall recommence mandatory lead service line replacement at the same
two-year rolling average rate, unless the State has designated an
alternate replacement rate under paragraph (g)(9) of this section.
    (7) The water system may also cease mandatory lead service line
replacement if the system has no remaining lead status unknown service
lines in its inventory and obtains refusals to conduct full lead
service line replacement or non-responses from every remaining customer
in its distribution system served by either a full or partial lead
service line, or a galvanized requiring replacement service line. For
purposes of this paragraph (g)(7) and in accordance with Sec.
141.90(e), a water system must provide

documentation to the State of customer refusals including a refusal
signed by the customer, documentation of a verbal statement made by the
customer refusing replacement, or documentation of no response from the
customer after the water system made a minimum of two good faith
attempts to reach the customer regarding full lead service line
replacement. If the water system's 90th percentile exceeds the lead
action level again, it must contact all customers served by a full or
partial lead service line or a galvanized requiring replacement service
line with an offer to replace the customer-owned portion. Nothing in
this paragraph (g)(7) requires the water system 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 tap sampling period in which
lead action level was exceeded.
    (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 the State
determines 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 under paragraph (g) of this section.
    (h) Reporting to demonstrate compliance to State. To demonstrate
compliance with paragraphs (a) through (g) of this section, a system
shall report to the State the information specified in Sec.  141.90(e).

0
9. Amend Sec.  141.85 by:
0
a. Revising the section heading, introductory text, and paragraphs
(a)(1) introductory text and (a)(1)(ii);
0
b. Adding paragraph (a)(1)(vii);
0
c. Revising paragraphs (b)(2) introductory text, (b)(2)(ii)(B)
introductory text, and (b)(2)(ii)(B)(1);
0
c. Adding paragraph (b)(2)(ii)(B)(7);
0
d. Removing paragraph (b)(2)(ii)(C);
0
e. Revising paragraphs (b)(2)(vii), (b)(4) introductory text,
(b)(4)(iii), (b)(6), and (d)(1), (2), and (4); and
0
f. Adding paragraphs (e) through (j).
    The revisions and additions read as follows:

Sec.  141.85  Public education and supplemental monitoring and
mitigation 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 sampled, as specified in paragraph (d) of this section. A water
system with lead, galvanized requiring replacement, or lead status
unknown service lines must deliver public education materials to
persons with a lead, galvanized requiring replacement, or lead status
unknown service line as specified in paragraphs (e) through (g) of this
section. All community water systems must conduct annual outreach to
local and State health agencies as outlined in paragraph (i) of this
section. A community water system serving more than 10,000 persons that
fails to meet its annual lead service line replacement goal as required
under Sec.  141.84(f) shall conduct outreach activities as specified in
paragraph (h) 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 shall offer to sample the tap water of any customer who
requests it in accordance with paragraph (c) of this section. All small
community water systems and non-transient non-community water systems
that elect to implement POU devices under Sec.  141.93 must provide
public education materials to inform users how to properly use POU
devices in accordance with paragraph (j) of this section.
    (a) * * *
    (1) Community water systems and non-transient non-community water
systems. Water systems must include the following elements in printed
materials (e.g., brochures and pamphlets) in the same order as listed
in paragraphs (a)(1)(i) through (vii) of this section. In addition,
language in paragraphs (a)(1)(i), (ii), and (vi) of this section must
be included in the materials, exactly as written, except for the text
in brackets in paragraphs (a)(1)(i), (ii), and (vi) of this section for
which the water system must include system-specific information. Any
additional information presented by a water system must be consistent
with the information in paragraphs (a)(1) through (vii) of this section
and be in plain language that can be understood by the general public.
Water systems must submit all written public education materials to the
State prior to delivery. The State may require the system to obtain
approval of the content of written public materials prior to delivery.
Water systems may change the mandatory language in paragraphs (a)(1)(i)
and (ii) of this section only with State approval.
* * * * *
    (ii) Health effects of lead. Exposure to lead in drinking water can
cause serious health effects in all age groups. Infants and children
can have decreases in IQ and attention span. Lead exposure can lead to
new learning and behavior problems or exacerbate existing learning and
behavior problems. The children of women who are exposed to lead before
or during pregnancy can have increased risk of these adverse health
effects. Adults can have increased risks of heart disease, high blood
pressure, kidney or nervous system problems.
* * * * *
    (vii) Information on lead service lines. For systems with lead
service lines, discuss opportunities to replace lead service lines and
explain how to access the service line inventory so the consumer can
find out if they have a lead service line. Include information on
programs that provide financing solutions to assist property owners
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 property owner notifies them they are
replacing their portion of the lead service line.
* * * * *
    (b) * * *
    (2) A community water system that exceeds the lead action level on
the basis of tap water samples collected in accordance with Sec.
141.86, and that is not already conducting public education tasks under
this section, must conduct the public education tasks under this
section within 60 days after the end of the tap sampling period in
which the exceedance occurred:
* * * * *
    (ii) * * *
    (B) Contact customers who are most at risk by delivering materials
that meet the content requirements of paragraph (a) of this section to
the following organizations listed in paragraphs (b)(2)(ii)(B)(1)
through (7) of this section that are located within the water system's
service area, along with an informational notice that encourages
distribution to all the organization's potentially affected customers
or community water system's users:
    (1) Schools, child care facilities, and school boards.
* * * * *
    (7) Obstetricians-Gynecologists and Midwives.
* * * * *
    (vii) For systems that are required to conduct monitoring annually
or less

frequently, the end of the tap sampling period is September 30 of the
calendar year in which the sampling occurs, or, if the State has
established an alternate tap sampling period, the last day of that
period.
* * * * *
    (4) Within 60 days after the end of the tap sampling period in
which the exceedance occurred (unless it already is repeating public
education tasks pursuant to paragraph (b)(5) of this section), a non-
transient non-community water system shall deliver the public education
materials specified by paragraph (a) of this section as follows:
* * * * *
    (iii) For systems that are required to conduct monitoring annually
or less frequently, the end of the tap sampling period is September 30
of the calendar year in which the sampling occurs, or, if the State has
established an alternate tap sampling period, the last day of that
period.
* * * * *
    (6) A water system may discontinue delivery of public education
materials if the system is at or below the lead action level during the
most recent six-month tap sampling monitoring period conducted pursuant
to Sec.  141.86. Such a system shall recommence public education in
accordance with this section if it subsequently exceeds the lead action
level during any tap sampling period.
* * * * *
    (d) * * *
    (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 building where the tap was sampled).
    (2) Timing of notification. A water system must provide the
consumer notice as soon as practicable but no later than the following
timeframes:
    (i) For individual samples that do not exceed 15 [mu]g/L of lead,
no later than 30 days after the water system learns of the tap
monitoring results.
    (ii) For individual samples that exceed 15 [mu]g/L of lead, as soon
as practicable but no later than 3 calendar days after the water system
learns of the tap monitoring results. Water systems that choose to mail
the notification must assure those letters are postmarked within three
days.
* * * * *
    (4) Delivery. (i) For lead tap sample results that do not exceed 15
[mu]g/L, the water systems must provide consumer notice to persons
served at the tap that was sampled, 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.
    (ii) For lead tap sample results that exceed 15 [mu]g/L, the water
systems must provide consumer notice to persons served by the tap that
was sampled; such notice must be provided electronically or by phone,
hand delivery, by mail, or another method approved by the State.
    (e) Notification of known or potential service line containing
lead--(1) Notification requirements. All water systems with lead,
galvanized requiring replacement, or lead status unknown service lines
in their inventory pursuant to Sec.  141.84(a) must inform all persons
served by the water system at the service connection with a lead,
galvanized requiring replacement, or lead status unknown service line.
    (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 entire service connection is no longer a lead,
galvanized requiring replacement, or lead status unknown service line.
For new customers, water systems shall also provide the notice at the
time of service initiation.
    (3) Content--(i) Persons served by a confirmed lead service line.
The notice must include a statement that the person's service line is
lead, an explanation of the health effects of lead that meets the
requirements of paragraph (a)(1)(ii) of this section, steps persons at
the service connection can take to reduce exposure to lead in drinking
water, information about opportunities to replace lead service lines as
well as programs that provide financing solutions to assist property
owners 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 property owner notifies them they are
replacing their portion of the lead service line.
    (ii) Persons served by a galvanized requiring replacement service
line. The notice must include a statement that the person's service
line is galvanized requiring replacement, an explanation of the health
effects of lead, steps persons at the service connection can take to
reduce exposure to lead in drinking water, and information about
opportunities for replacement of the service line.
    (iii) Persons served by a lead status unknown service line. The
notice must include a statement that the person's service line material
is unknown but may be lead, an explanation of the health effects of
lead that meets the requirements of paragraph (a)(1)(ii) of this
section, steps persons at the service connection 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 the
water system at the service connection with a lead, galvanized
requiring replacement, or lead status unknown service line, by mail or
by another method approved by the State.
    (f) Notification due to a disturbance to a known or potential
service line containing lead. (1) Water systems that cause disturbance
to a lead, galvanized requiring replacement, or lead status unknown
service line that results in the water to an individual service line
being shut off or bypassed, such as operating a valve on a service line
or meter setter, and without conducting a partial or full lead service
line replacement, must provide the persons served by the water system
at the service connection with information about the potential for
elevated lead levels in drinking water as a result of the disturbance
as well as instructions for a flushing procedure to remove particulate
lead. The water system must comply with the requirements in this
paragraph (f)(1) before the affected service line is returned to
service.
    (2) If the disturbance of a lead, galvanized requiring replacement,
or lead status unknown service line results from the replacement of an
inline water meter, a water meter setter, or gooseneck, pigtail, or
connector, the water system must provide the person served by the water
system at the service connection with information about the potential
for elevated lead levels in drinking water as a result of the
disturbance, public education materials that meet the content
requirements in paragraph (a) of this section, a pitcher filter or
point-of-use device certified by an American National Standards
Institute accredited certifier to reduce lead, instructions to use the
filter, and six months of filter replacement cartridges. The water
system must comply with the requirements of this paragraph (f)(2)
before the affected service line is returned to service.

    (3) A water system that conducts a partial or full lead service
line replacement must follow procedures in accordance with the
requirements in Sec.  141.84(d)(1)(i) through (iv) and (e)(1)(i)
through (iv), respectively.
    (g) Information for persons served by known or potential service
lines containing lead when a system exceeds the lead trigger level--(1)
Content. All water systems with lead service lines that exceed the lead
trigger level of 10 [mu]g/L must provide persons served by the water
system at the service connection with a lead, galvanized requiring
replacement, or lead status unknown service line information regarding
the water system's lead service line replacement program and
opportunities for replacement of the lead service line.
    (2) Timing. Waters systems must send notification within 30 days of
the end of the tap sampling 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 are
at or below the lead trigger level.
    (3) Delivery. The notice must be provided to persons served at the
service connection with a lead, galvanized requiring replacement, or
lead status unknown service line, by mail or by another method approved
by the State.
    (h) Outreach activities for failure to meet the lead service line
replacement goal. (1) In the first year after a community water system
that serves more than 10,000 persons does not meet its annual lead
service line replacement goal as required under Sec.  141.84(f), it
must conduct one outreach activity from the following list in the
following year until the water system meets its replacement goal or
until tap sampling shows that the 90th percentile for lead is at or
below the trigger level of 10 [mu]g/L for two consecutive tap sampling
monitoring periods:
    (i) Send certified mail to customers with a lead or galvanized
requiring replacement service line to inform them about the water
system's goal-based lead service line replacement program and
opportunities for replacement of the service line.
    (ii) Conduct a townhall meeting.
    (iii) Participate in a community event to provide information about
its lead service line replacement program and distribute public
education materials that meet the content requirements in paragraph (a)
of this section.
    (iv) Contact customers by phone, text message, email, or door
hanger.
    (v) Use another method approved by the State to discuss the lead
service line replacement program and opportunities for lead service
line replacement.
    (2) After the first year following a trigger level exceedance, any
water system that thereafter continues to fail to meet its lead service
line replacement goal must conduct one activity from paragraph (h)(1)
of this section and two additional outreach activities per year from
the following list:
    (i) Conduct social media campaign.
    (ii) Conduct outreach via newspaper, television, or radio.
    (iii) 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.
    (iv) Visit targeted customers to discuss the lead service line
replacement program and opportunities for replacement.
    (3) The water system may cease outreach activities when tap
sampling shows that the 90th percentile for lead is at or below the
trigger level of 10 [mu]g/L for two consecutive tap sampling monitoring
periods or when all customer-side lead or galvanized requiring
replacement service line owners refuse to participate in the lead
service line replacement program. For purposes of this paragraph
(h)(3), a refusal includes a signed statement by the customer refusing
lead service line replacement, or documentation by the water system of
a verbal refusal or of no response after two good faith attempts to
reach the customer.
    (i) Public education to local and State health agencies--(1) Find-
and-fix results. All community water systems must provide information
to local and State health agencies about find-and-fix activities
conducted in accordance with Sec.  141.82(j) including the location of
the tap sample site that exceeded 15 [micro]g/L, the result of the
initial tap sample, the result of the follow up tap sample, the result
of water quality parameter monitoring, and any distribution system
management actions or corrosion control treatment adjustments made.
    (2) Timing and content. Community water systems must annually send
copies of the public education materials provided under paragraph (a)
of this section, and of paragraph (h)(1) of this section for actions
conducted in the previous calendar year no later than July 1 of the
following year.
    (3) Delivery. Community water systems shall send public education
materials and find-and-fix information to local and State health
agencies by mail or by another method approved by the State.
    (j) Public education requirements for small water system compliance
flexibility POU devices--(1) Content. All small community water systems
and non-transient non-community water systems that elect to implement
POU devices under Sec.  141.93 must provide public education materials
to inform users how to properly use POU devices to maximize the units'
effectiveness in reducing lead levels in drinking water.
    (2) Timing. Water systems shall provide the public education
materials at the time of POU device delivery.
    (3) Delivery. Water systems shall provide the public education
materials in person, by mail, or by another method approved by the
State, to persons at locations where the system has delivered POU
devices.

0
10. Amend Sec.  141.86 by revising paragraphs (a), (b), (d), (e), (f)
introductory text, and (g) introductory text and adding paragraphs (h)
and (i) to 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 identify a pool of targeted sampling sites based on
the service line inventory conducted in accordance with Sec.
141.84(a), 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. Sampling sites may not include sites with installed
point-of-entry (POE) treatment devices and taps used at sampling sites
may not have point-of-use (POU) devices designed to remove inorganic
contaminants, except for water systems monitoring under Sec.
141.93(a)(3)(iv) and water systems using these devices for the primary
drinking water tap to meet other primary and secondary drinking water
standards and all service connections have POEs or POUs to provide
localized treatment for compliance with the other drinking water
standards. Lead and copper sampling results for systems monitoring
under Sec.  141.93(a)(3)(iv) may not be used for the purposes of
meeting the criteria for reduced monitoring specified in paragraph
(d)(4) of this section.
    (2) A water system must use the information on lead, copper, and
galvanized iron or steel that is required to be identified under Sec.
141.42(d) when conducting a materials evaluation and 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.
    (3) The sampling sites for a community water system's sampling pool
must consist of single-family structures that are served by a lead
service line (``Tier 1 sampling sites''). When multiple-family
residences comprise at least 20 percent of the structures served by the
water system, the system may include these types of structures in its
Tier 1 sampling pool, if served by a lead service line. Sites with lead
status unknown service lines must not be used as Tier 1 sampling sites.
    (4) A community water system with insufficient Tier 1 sampling
sites must complete its sampling pool with ``Tier 2 sampling sites,''
consisting of buildings, including multiple-family residences that are
served by a lead service line. Sites with lead status unknown service
lines must not be used as Tier 2 sampling sites.
    (5) A community water system with insufficient Tier 1 and Tier 2
sampling sites must complete its sampling pool with ``Tier 3 sampling
sites,'' consisting of single-family structures that contain galvanized
lines identified as being downstream of a lead service line (LSL)
currently or in the past, or known to be downstream of a lead
gooseneck, pigtail or connector. Sites with lead status unknown service
lines must not be used as Tier 3 sampling sites.
    (6) A community water system with insufficient Tier 1, Tier 2, and
Tier 3 sampling sites must complete its sampling pool with ``Tier 4
sampling sites,'' consisting of single-family structures that contain
copper pipes with lead solder installed before the effective date of
the State's applicable lead ban. Sites with lead status unknown service
lines must not be used as Tier 4 sampling sites.
    (7) A community water system with insufficient Tier 1, Tier 2, Tier
3, and Tier 4 sampling sites must complete its sampling pool with
``Tier 5 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)(7), 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. Water systems may use non-residential