[Federal Register Volume 86, Number 10 (Friday, January 15, 2021)]
[Rules and Regulations]
[Pages 4198-4312]
[FR Doc No: 2020-28691]

Vol. 86

Friday,

No. 10

January 15, 2021

Part II

Environmental Protection Agency

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40 CFR Parts 141 and 142

National Primary Drinking Water Regulations: Lead and Copper Rule
Revisions; Final Rule

Federal Register / Vol. 86, No. 10 / Friday, January 15, 2021 / Rules
and Regulations

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 141 and 142

[EPA-HQ-OW-2017-0300; FRL-10019-23-OW]
RIN 2040-AF15

National Primary Drinking Water Regulations: Lead and Copper Rule
Revisions

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: The Environmental Protection Agency (EPA) is publishing final
regulatory revisions to the National Primary Drinking Water Regulation
(NPDWR) for lead and copper under the authority of the Safe Drinking
Water Act (SDWA). These revised requirements provide greater and more
effective protection of public health by reducing exposure to lead and
copper in drinking water. The rule will better identify high levels of
lead, improve the reliability of lead tap sampling results, strengthen
corrosion control treatment requirements, expand consumer awareness and
improve risk communication. This final rule requires, for the first
time, community water systems to conduct lead-in-drinking-water testing
and public education in schools and child care facilities. In addition,
the rule will accelerate lead service line replacements by closing
existing regulatory loopholes, propelling early action, and
strengthening replacement requirements.

DATES:
    Effective date: This final rule is effective as of March 16, 2021.
For judicial review purposes, this final rule is promulgated as of
January 15, 2021.
    Compliance dates: The compliance date for the revisions to 40 CFR
part 141, subpart I, is set forth in Sec.  141.80(a). The compliance
date for the revisions to 40 CFR 141.2 is January 16, 2024, and the
compliance date for 40 CFR 141.31 is January 16, 2024. The compliance
date for changes made to 40 CFR part 141, subpart O (40 CFR
141.153(d)(4)(vi) and (xi) and 141.154(d)(1)), is January 16, 2024. The
compliance date for changes made to 40 CFR part 141, subpart Q (Sec.
141.202 and appendices A and B), is January 16, 2024.

ADDRESSES: EPA has established a docket for this action under Docket ID
No. EPA-HQ-OW-2017-0300. All documents in the docket are listed on the
http://www.regulations.gov website. Although listed in the index, some
information is not publicly available, e.g., Confidential Business
Information or other information whose disclosure is restricted by
statute. Certain other material, such as copyrighted material, is not
placed on the internet and will be publicly available only in hard copy
form.

FOR FURTHER INFORMATION CONTACT: Jeffrey Kempic, Standards and Risk
Management Division, Office of Ground Water and Drinking Water, U.S.
Environmental Protection Agency, 1200 Pennsylvania Ave. NW, Mail Code
4607M, Washington, DC 20460; telephone number:<PHONE_NUMBER> (TTY 800-
877-8339); email address<EMAIL_ADDRESS>For more information
visit https://www.epa.gov/dwreginfo/lead-and-copper-rule.

SUPPLEMENTARY INFORMATION:

I. General Information
    A. What are EPA's final revisions?
    B. Does this action apply to me?
II. Background
    A. Health Effects of Lead and Copper
    B. Statutory Authority
    C. Regulatory History
III. Revisions to 40 CFR Part 141, Subpart I, Control of Lead and
Copper
    A. Lead Trigger Level
    1. Proposed Revisions
    2. Public Comment and EPA's Response
    3. Final Rule Requirements
    B. Corrosion Control Treatment
    1. Proposed Revisions
    2. Public Comment and EPA's Response
    3. Final Rule Requirements
    C. Lead Service Line Inventory
    1. Proposed Revisions
    2. Public Comment and EPA's Response
    3. Final Rule Requirements
    D. Lead Service Line Replacement
    1. Proposed Revisions
    2. Public Comment and EPA's Response
    3. Final Rule Requirements
    E. Compliance Alternatives for a Lead Action Level Exceedance
for Small Community Water Systems and Non-Transient, Non-Community
Water Systems
    1. Proposed Revisions
    2. Public Comment and EPA's Response
    3. Final Rule Requirements
    F. Public Education
    1. Proposed Revisions
    2. Public Comment and EPA's Response
    3. Final Rule Requirements
    G. Tap Water Sampling
    1. Proposed Revisions
    2. Public Comment and EPA's Response
    3. Final Rule Requirements
    H. Water Quality Parameter Monitoring
    1. Proposed Revisions
    2. Public Comment and EPA's Response
    3. Final Rule Requirements
    I. Source Water Monitoring
    1. Proposed Revisions
    2. Public Comment and EPA's Response
    3. Final Rule Requirements
    J. Public Education and Sampling at Schools and Child Care
Facilities
    1. Proposed Revisions
    2. Public Comment and EPA's Response
    3. Final Rule Requirements
    K. Find-and-Fix
    1. Proposed Revisions
    2. Public Comment and EPA's Response
    3. Final Rule Requirements
    L. Water System Reporting Requirements
    1. Proposed Revisions
    2. Public Comment and EPA's Response
    3. Final Rule Requirements
IV. Other Revisions to 40 CFR Part 141
    A. Consumer Confidence Report
    1. Proposed Revisions
    2. Public Comment and EPA's Response
    3. Final Rule Requirements
    B. Public Notification
    1. Proposed Revisions
    2. Public Comment and EPA's Response
    3. Final Rule Requirements
    C. Definitions
    1. Proposed Revisions
    2. Public Comment and EPA's Response
    3. Final Rule Requirements
V. Rule Implementation and Enforcement
    A. What are State recordkeeping and reporting requirements?
    1. Proposed Revisions
    2. Public Comment and EPA's Response
    3. Final Rule Requirements
    B. What are the special primacy requirements?
    1. Proposed Revisions
    2. Public Comment and EPA's Response
    3. Final Rule Requirements
VI. Economic Analysis
    A. Public Comments on the Economic Analysis of the Proposed Rule
and EPA Response
    B. Affected Entities and Major Data Sources Used To Characterize
the Sample Universe
    C. Overview of the Cost-Benefit Model
    D. Cost Analysis
    1. Drinking Water System Implementation and Administrative Costs
    2. Sampling Costs
    3. Corrosion Control Treatment Costs
    4. Lead Service Line Inventory and Replacement Costs
    5. Point-of-Use Costs
    6. Public Education and Outreach Costs
    7. Annualized Per Household Costs
    8. Primacy Agency Costs
    9. Costs and Ecological Impacts Associated With Additional
Phosphate Usage
    10. Summary of Rule Costs
    E. Benefits Analysis
    1. Modeled Drinking Water Lead Concentrations
    2. Impacts on Childhood IQ
    3. Impacts on Adult Blood Lead Levels
    4. Total Monetized Benefits
    F. Cost-Benefit Comparison
    1. Non-Monetized Costs
    2. Non-Quantified Non-Monetized Benefits
    G. Other Regulatory Options Considered
    1. Lead Public Education and Sampling at Schools and Child Care
Facilities
    2. Lead Tap Sampling Requirements for Water Systems With Lead
Service Lines
    3. Reporting of LSL-Related Information
    4. Small System Flexibility
VII. Administrative Requirements
    A. Executive Order 12866: Regulatory Planning and Review and
Executive Order 13563: Improving Regulation and Regulatory Review

    B. Executive Order 13771: Reducing Regulations and Controlling
Regulatory Cost
    C. Paperwork Reduction Act (From the Office of Mission Support's
Information Collection Request Center) (PRA)
    D. Regulatory Flexibility Act as Amended by the Small Business
Regulatory Fairness Act (RFA)
    E. The Unfunded Mandates Reform Act (UMRA)
    F. Executive Order 13132: Federalism
    G. Executive Order 13175: Consultation and Coordination With
Indian Tribal Governments
    H. Executive Order 13045: Protection of Children From
Environmental Health and Safety Risks
    I. Executive Order 13211: Actions That Significantly Affect
Energy Supply, Distribution, or Use
    J. National Technology Transfer and Advancement Act of 1995
    K. Executive Order 12898: Federal Actions To Address
Environmental Justice in Minority Populations and Low-Income
Populations
    L. Consultations With the Science Advisory Board and the
National Drinking Water Advisory Council
    M. Consultation With the Department of Health and Human Services
Under SDWA Section 1412(d)
    N. Congressional Review Act (CRA)
VIII. References

I. General Information

    The United States has made tremendous progress in lowering
children's blood lead levels. As a result of multiple Federal laws and
regulations, including the 1973 phase-out of lead in automobile
gasoline (40 CFR part 80, subpart B), the 1978 Federal regulation
banning lead paint for residential and consumer use (16 CFR part 1303),
the 1991 LCR (40 CFR part 141, subpart I), and the 1995 ban on lead in
solder in food cans (21 CFR 189.240), the median concentration of lead
in the blood of children aged 1 to 5 years dropped from 15 micrograms
([micro]g) per deciliter in 1976-1980 to 0.7 [micro]g per deciliter in
2015-2016, a decrease of 95 percent (USEPA, 2019a).
    Although childhood blood lead levels have been substantially
reduced as a result of these actions, exposure to lead in the
environment continues to be a concern, especially for vulnerable
populations such as children and pregnant women. Data evaluated by the
National Toxicology Program (NTP, 2012) demonstrates that there is
sufficient evidence to conclude that there are adverse health effects
associated with low-level lead exposure. Moreover, no safe blood lead
level in children has been identified (https://www.cdc.gov/nceh/lead/prevention/default.htm). Sources of lead include lead-based paint,
drinking water, and soil contaminated by historical sources. The
Federal Action Plan (Action Plan) to Reduce Childhood Lead Exposures
and Associated Health Impacts, issued in December 2018, provides a
blueprint for reducing further lead exposure and associated harm
through collaboration among Federal agencies and with a range of
stakeholders, including states, tribes, and local communities, along
with businesses, property owners, and parents. The Action Plan is the
product of the President's Task Force on Environmental Health Risks and
Safety Risks to Children (Task Force). The Task Force is comprised of
17 Federal departments and offices including the U.S. Department of
Health and Human Services (HHS) and the U.S Department of Housing and
Urban Development, which co-chaired the development of the Action Plan
with EPA.
    Through this plan, EPA committed to reducing lead exposures from
multiple sources including paint, ambient air, and soil and dust
contamination, especially to children who are among the most vulnerable
to the effects of lead.
    On June 21, 2019, EPA announced new, tighter standards for lead in
dust on floors and windowsills to protect children from the harmful
effects of lead exposure. The standards were lowered from 40 [micro]g
of lead in dust per square foot (ft\2\) on floors and 250 [micro]g of
lead in dust per ft\2\ on interior windowsills, to 10 [micro]g/ft\2\
and 100 [micro]g/ft\2\, respectively. The lead hazard standards help
property owners, lead paint professionals, and government agencies
identify lead hazards in residential paint, dust and soil. On June 19,
2020 EPA released a proposal to lower the clearance levels for lead in
dust on floors and windowsills after lead removal activities from 40
[micro]g/ft\2\ to 10 [micro]g/ft\2\ for floor dust and from 250
[micro]g/ft\2\ to 100 [micro]g/ft\2\ for windowsill dust (85 FR 37810).
The dust lead clearance levels are used to demonstrate that abatement
activities effectively and permanently eliminate those hazards. They
apply in most pre-1978 housing and child-occupied facilities. The
proposed, tighter standards would increase the effectiveness of
abatement in pre-1978 homes and child care facilities.
    To address lead in soil, EPA will continue to remove, remediate,
and take corrective actions at contaminated sites, including Superfund,
Resource Conservation and Recovery Act (RCRA) Corrective Action, and
other cleanup sites. EPA will also continue to work with state and
tribal air agencies to help nonattainment areas meet the National
Ambient Air Quality Standards. EPA is also focused on conducting
critical research and improving public awareness by consolidating and
streamlining Federal messaging.
    Lead and copper enter drinking water mainly from the corrosion of
plumbing materials containing lead and copper. Lead was widely used in
plumbing materials until Congress prohibited the use or introduction
into commerce of pipes and pipe fittings and fixtures that contained
more than eight percent lead and solder or flux that contained more
than 0.2 percent lead in 1986. On September 1, 2020, EPA published the
final rule: Use of Lead Free Pipes, Fittings, Fixtures, Solder, and
Flux for Drinking Water. The Lead-Free final rule significantly limits
the lead content allowed in plumbing materials (e.g., pipes, fittings,
and fixtures) used in new construction and replacement of existing
plumbing. Specifically, the Lead-Free rule reduces the percentage of
lead content allowed in these materials from eight percent to 0.25
percent in accordance with the 2011 Reduction of Lead in Drinking Water
Act.
    Many buildings were constructed prior to the restrictions on the
use of plumbing materials that contained lead. There are currently an
estimated 6.3 to 9.3 million homes served by lead service lines (LSLs)
in thousands of communities nationwide, in addition to millions of
older buildings with lead solder and faucets that contain lead. To
reduce exposure to lead through drinking water, the Action Plan
highlights several key actions, including EPA's commitment to making
regulatory changes to implement the statutory definition of lead-free
plumbing products and assisting schools and child care centers with the
3Ts approach (Training, Testing, and Taking Action) for lead in
drinking water. The Action Plan also highlights EPA's support to states
and communities by identifying funding opportunities through the
Drinking Water State Revolving Fund and the Water Infrastructure
Finance and Innovation Act loan program for updating and replacing
drinking water infrastructure. In addition, the Action Plan highlights
three newly authorized grant programs under the Water Infrastructure
Improvements for the Nation (WIIN) Act, for which Congress appropriated
$50 million in fiscal year (FY) 2018, to fund grants to small and
disadvantaged communities for developing and maintaining
infrastructure, for lead reduction projects, and to support the
voluntary testing of drinking water in schools and child care centers.
The Action Plan also highlights the importance of preventing lead
exposure from drinking water by working with states, tribes, and local

stakeholders to share best practices and tools to better implement the
NPDWR for Lead and Copper. For more information about the Federal Lead
Action Plan see https://www.epa.gov/sites/production/files/2018-12/documents/fedactionplan_lead_final.pdf.
    Since the implementation of the Lead and Copper Rule (LCR),
drinking water exposures have declined significantly, resulting in
major improvements in public health. For example, the number of the
nation's large drinking water systems that have exceeded the LCR action
level of 15 parts per billion has decreased by over 90 percent. Between
2017 and 2019, fewer than 5 percent of all water systems reported an
action level exceedance (EPA-815-F-19-007). Despite this progress,
there is a compelling need to modernize and improve the rule by
strengthening its public health protections and clarifying its
implementation requirements to make it more effective and more readily
enforceable.
    The LCR is a complicated rule due, in part, to the need to control
corrosivity of drinking water as it travels through often antiquated
distribution and plumbing systems on the way to the consumer's tap.
States and public water systems need expertise and resources to
identify the sampling locations and to work with customers to collect
samples for analysis. Even greater expertise is needed for systems and
states to identify the optimal corrosion control treatment and water
quality parameter monitoring to assure that lead and copper levels are
reduced to the extent feasible. The determination of the optimal
corrosion control treatment is specific to each water system because it
is based on the specific chemistry of the system's source water, and
must be designed and implemented to take into account treatments used
to comply with other applicable drinking water standards (56 FR 26487).
    Water systems cannot unilaterally implement all of the actions that
are needed to reduce levels of lead in drinking water. Homeowners must
also be engaged to assure successful LSL replacement because, in most
communities, a portion of the LSL is owned by the water system and the
remaining portion is the property of the homeowner. Water systems must
also engage with consumers to encourage actions such as flushing of
taps before use to reduce their exposure to lead in drinking water,
where necessary. The ability of water systems to successfully engage
with consumers is critical to reducing drinking water lead exposure.
    EPA sought input over an extended period on ways in which the
Agency could address the challenges to further reducing drinking water
lead exposure. Section VII of this preamble describes the engagements
the Agency has had with small water systems, state and local officials,
the Science Advisory Board, and the National Drinking Water Advisory
Council (NDWAC). The Science Advisory Board provided recommendations in
2012 (SAB, 2012) and provided recommendations on the proposed Lead and
Copper Rule revisions (LCRR) in 2020 (SAB, 2020). The NDWAC also
provided recommendations on potential LCR revisions to EPA. The NDWAC
provided written recommendations in December 2015 (NDWAC, 2015) and
provided input to the Agency as part of consultation on the proposed
LCRR in December 2019.
    This final rule includes a suite of actions to address lead
contamination in drinking water that, taken together, will improve the
LCR and further reduce lead exposure from the previous LCR, resulting
in an enduring positive public health impact. This approach focuses on
six key areas:
    a. Identifying areas most impacted. To help identify areas with the
greatest potential for lead contamination of drinking water and most in
need of remediation, EPA's final rule requires that all water systems
complete and maintain a LSL inventory and collect tap samples from
homes with LSLs if lead is present in the distribution system. To
reduce elevated levels of lead in certain locations, EPA's final rule
also requires water systems to engage in a ``find-and-fix'' process to
identify the causes of these elevated levels as well as take potential
actions to reduce lead levels.
    b. Strengthening treatment requirements. EPA is finalizing expanded
requirements for corrosion control treatment (CCT) based on tap
sampling results. The final rule also establishes a new trigger level
of 10 [micro]g/L. At this trigger level, systems that currently treat
for corrosion are required to re-optimize their existing treatment.
Systems that do not currently treat for corrosion will be required to
conduct a corrosion control study so that the system is prepared to
respond quickly if necessary. Flexibility is important for small
systems so that they can protect public health by taking the treatment
actions that make sense for their communities. The LCRR provides new
alternatives to CCT for small systems including Point-of-Use (POU)
treatment and replacement of lead bearing plumbing materials.
    c. Systematically replacing lead service lines. The final LCRR
requires water systems with high lead levels to initiate LSL removal,
permanently reducing a significant source of lead in many communities.
All water systems with LSLs or lead status unknown service lines must
create an LSLR plan by the rule compliance date. The more stringent
sampling requirements in the final rule will better identify elevated
lead levels, which will result in more systems replacing LSLs. Systems
that are above the trigger level but at or below the lead action level
must conduct replacements at a goal rate approved by the state, and,
systems that are above the action level, must annually replace a
minimum of three percent per year, based upon a 2 year rolling average
of the number of known or potential LSLs in the inventory at the time
the action level exceedance occurs. Systems cannot end their
replacement program until they demonstrate lead levels less than the
action level for two years. Only full LSL replacements will be counted
towards the required rate, not partials and not ``in lieu of'' samples.
The final rule requires water systems to provide awareness to homes
with LSLs annually, and replace the water system-owned portion of an
LSL when a customer chooses to replace their customer-owned portion of
the line within 45 days with the ability to have up to 180 days with
notification to the state.
    d. Increasing sampling reliability. EPA is changing the criteria
for selecting homes at which to collect tap samples and the way in
which those samples are collected. EPA is requiring tap sample site
selection to focus on sites with LSLs (where present) and is requiring
a new way to collect tap samples at these sites. Systems must collect
fifth liter samples that are representative of water that has been in
the LSL for several hours, which will provide better information on the
highest concentration of lead in drinking water. The final LCR
revisions prohibit tap sampling instructions that call for pre-
stagnation flushing or, the cleaning or removing of faucet aerators,
and include a requirement that tap samples be collected in bottles with
a wide-mouth configuration. Collectively, these new, more stringent
sampling requirements will better identify elevated lead levels and
result in more water systems taking required lead mitigation actions.
    e. Improving risk communication. EPA is requiring systems to notify
consumers of a system-wide action level exceedance within 24 hours. For
individual tap samples that exceed 15 [micro]g/L, EPA is requiring
systems to notify

the individual consumer within three days. EPA is also requiring the
consistent use of clear and concise language in public notifications
and all public education materials including the LCR Public Education
(PE) and Consumer Confidence Report (CCR) on the health effects of
exposure to lead in drinking water. The final rule increases the
number, forms, and comprehensiveness of public education materials on
lead in drinking water that are provided to the public. It also
requires systems to conduct regular outreach to customers with LSLs.
Systems must make their LSL inventory publicly available and must
notify occupants of homes with LSL every year about their LSL, drinking
water exposure risks, and mitigation options, including removal. The
final rule's requirements to provide understandable and consistent
information about the levels of lead in drinking water, the sources of
lead in a system, and the risks of lead in drinking water, will
increase public actions to limit exposure to lead in drinking water.
    f. Protecting children in schools. Since children are at most risk
of significant harm from lead exposure, EPA is requiring that community
water systems (CWS) test for lead in drinking water in schools and
child care facilities. Systems must conduct drinking water sampling at
each elementary school and each child care facility they serve over no
more than five years, testing 20 percent of the facilities they serve
each year. The system will be required to provide sampling results to
the school or child care facility and information on actions that can
be taken by the school or child care facility to reduce lead in the
drinking water. The system will also be required to provide information
to the school or child care facility on methods to communicate results
to users of the facility and parents. CWSs are also required to provide
testing to secondary schools on request during the 5 years of mandatory
elementary and child care facility testing, and also to elementary
schools and child care facilities on request after the first round of
mandatory testing. These requirements will provide schools and child
care facilities with an understanding of how to create and manage a
drinking water testing program that is customizable to their needs and
an appreciation of the benefits of such a program.
    Through strengthened treatment procedures, expanded sampling, and
improved protocols for identifying lead in drinking water, EPA's LCR
revisions will require more water systems to progressively take more
actions to reduce lead levels at the tap. Additionally, by improving
transparency and communication, the rule is expected to increase
community awareness and accelerate the replacement of LSLs. By taking
these collective actions EPA, states, and water systems will implement
a proactive, holistic approach to more aggressively manage lead in
drinking water.

A. What are EPA's final revisions?

    EPA is promulgating revisions to the LCR that strengthen public
health protection and improve implementation of the regulation in the
following areas: Lead tap sampling; CCT; LSLR; consumer awareness; and
public education (PE). This final rule adopts a regulatory framework
recommended, in part, by state co-regulators through the Association of
State Drinking Water Administrators (ASDWA) and incorporates many
recommendations provided to EPA by the National Drinking Water Advisory
Council (NDWAC). NDWAC is a Federal Advisory Committee established
pursuant to section 1446 of the Safe Drinking Water Act (SDWA) that
provides EPA with advice and recommendations related to the national
drinking water program. EPA is finalizing revisions to the LCR that
will require water systems to take actions at lower lead tap water
levels than previously required; this will reduce lead in drinking
water and better protect public health. The Agency is establishing a
new lead ``trigger level'' of 10 [micro]g/L in addition to the 15
[micro]g/L lead action level. Public health improvements will be
achieved as water systems are required to take a progressive set of
actions to reduce lead levels at the tap. These actions are designed to
reduce lead and copper exposure by ensuring effective CCT and re-
optimization of CCT when the lead trigger level or action level is
exceeded; enhancing water quality parameter (WQP) monitoring; establish
a ``find-and-fix'' process to evaluate and remediate elevated lead at a
site where the individual tap sample exceeds 15 [micro]g/L; require
water systems to create an LSL inventory to identify the full extent of
LSLs in the system; ensure tap sampling pools are targeted to the sites
with elevated lead; and make consumers aware of the presence of a LSL,
if applicable, to facilitate replacement of LSLs. The LCR revisions
will improve tap sampling by improving the tap sampling protocol,
taking samples that are more representative of the highest levels of
lead in drinking water taps and better targeting higher risk sites for
lead contamination, i.e., sites with LSLs or lead containing plumbing
materials. EPA's revisions to the LCR Public Education (PE) and
Consumer Confidence Report (CCR) requirements will improve
communication with consumers. In addition, this final rule includes
requirements for CWSs to conduct lead in drinking water testing and PE
in schools and child care facilities.
    Together, these revisions to the existing framework and new
requirements will result in greater public health protection at all
sizes of CWSs and non-transient non-community water systems (NTNCWSs).
Implementation of the revisions will better identify when and where
lead contamination occurs, or has the potential to occur, and require
systems to take actions to address it more effectively and sooner than
under the previous rule.
    The following table compares the major differences between the
previous Lead and Copper Rule (LCR) (promulgated in 1991 and last
revised in 2007), the 2019 proposed Lead and Copper Rule revisions
(LCRR), and the final rule requirements. In general, requirements that
are unchanged are not listed.

----------------------------------------------------------------------------------------------------------------
            Previous LCR                          Proposed LCRR                          Final LCRR
----------------------------------------------------------------------------------------------------------------
                                    Action Level (AL) and Trigger Level (TL)
----------------------------------------------------------------------------------------------------------------
[cir] 90th percentile (P90) level     [cir] 90th percentile (P90) level     [cir] 90th percentile (P90) level
 above lead AL of 15 [micro]g/L or     above lead AL of 15 [micro]g/L or     above lead AL of 15 [micro]g/L or
 copper AL of 1.3 mg/L requires        copper AL of 1.3 mg/L requires more   copper AL of 1.3 mg/L requires more
 additional actions.                   actions than the current rule.        actions than the previous rule.
                                      [cir] Defines lead trigger level      [cir] Defines lead trigger level
                                       (TL) of 10  <=15 [micro]g/L      (TL) of 10 15 [mu]g/L:      [cir] P90 15 [mu]g/L:
 number of consecutive years meeting   Semi-annually at the standard         Semi-annually at the standard
 the following criteria:               number of sites.                      number of sites.
[cir] Serves <=50,000 people and <=   [cir] P90 10 to 15 [mu]g/  [cir] P90 10 to 15 [mu]g/
 lead & copper ALs.                    L: Annually at the standard number    L: Annually at the standard number
[cir] Serves any population size,      of sites.                             of sites.
 meets state-specified optimal water  [cir] P90 <=10 [mu]g/L:               [cir] P90 <=10 [mu]g/L:
 quality parameters (OWQPs), and <=   [ssquf] Annually and triennially at   [ssquf] Annually at the standard
 lead AL.                              reduced number of sites using same    number of sites and triennially at
                                       criteria as current rule except for   reduced number of sites using same
                                       large systems and the copper 90th     criteria as previous rule except
                                       percentile level is not considered.   copper 90th percentile level is not
                                      [ssquf] Every 9 years based on         considered.
                                       current rule requirements for a 9-   [ssquf] Every 9 years based on
                                       year monitoring waiver.               current rule requirements for a 9-
                                                                             year monitoring waiver.
    [cir] Triennial monitoring also
     applies to any system with lead
     and copper 90th percentile
     levels <=0.005 mg/L and <=0.65
     mg/L, respectively, for 2
     consecutive 6-month monitoring
     periods.
    [cir] 9-year monitoring waiver
     available to systems serving
     <=3,300.
----------------------------------------------------------------------------------------------------------------
                      Corrosion Control Treatment (CCT) and Water Quality Parameters (WQPs)
----------------------------------------------------------------------------------------------------------------
CCT:                                  CCT:                                  CCT:
[cir] Systems serving >50,000 people  [cir] Specifies CCT requirements for  [cir] Specifies CCT requirements for
 were required to install treatment    systems with 10 15      [cir] Systems with P90 level >15
 CCT steps if no longer exceed both    [mu]g/L:                              [mu]g/L:
 ALs for two consecutive 6-month      [cir] No CCT: must complete CCT       [cir] No CCT: must complete CCT
 monitoring periods.                   installation regardless of their      installation regardless of their
[cir] Systems must operate CCT to      subsequent P90 levels.                subsequent P90 levels.
 meet any primacy agency-designated   [cir] With CCT: must re-optimize      [cir] With CCT: must re-optimize
 OWQPs that define optimal CCT.        CCT.                                  CCT.
[cir] There is no requirement for     [cir] CWSs serving <=10,000 people    [cir] CWSs serving <=10,000 people
 systems to re-optimize.               and non-transient water systems       and non-transient water systems
                                       (NTNCWSs) can select an option        (NTNCWSs) can select an option
                                       other than CCT to address lead. See   other than CCT to address lead. See
                                       Small System Flexibility.             Small System Flexibility.
CCT Options: Includes alkalinity and  CCT Options: Removes calcium          CCT Options: Removes calcium
 pH adjustment, calcium hardness       hardness as an option and specifies   hardness as an option and specifies
 adjustment, and phosphate or          any phosphate inhibitor must be       any phosphate inhibitor must be
 silicate-based corrosion inhibitor.   orthophosphate.                       orthophosphate.
Regulated WQPs:                       Regulated WQPs:                       Regulated WQPs:
[cir] No CCT: pH, alkalinity,         [cir] Eliminates WQPs related to      [cir] Eliminates WQPs related to
 calcium, conductivity, temperature,   calcium hardness (i.e., calcium,      calcium hardness (i.e., calcium,
 orthophosphate (if phosphate-based    conductivity, and temperature).       conductivity, and temperature).
 inhibitor is used), silica (if
 silica-based inhibitor is used).
    [cir] With CCT: pH, alkalinity,
     and based on type of CCT either
     orthophosphate, silica, or
     calcium.

WQP Monitoring:                       WQP Monitoring:                       WQP Monitoring:
[cir] Systems serving >=50,000        [cir] Systems serving >=50,000        [cir] Systems serving >=50,000
 people must conduct regular WQP       people must conduct regular WQP       people must conduct regular WQP
 monitoring at entry points and        monitoring at entry points and        monitoring at entry points and
 within the distribution system.       within the distribution system.       within the distribution system.
[cir] Systems serving <=50,000        [cir] Systems serving <=50,000        [cir] Systems serving <=50,000
 people conduct monitoring only in     people must continue WQP monitoring   people must continue WQP monitoring
 those periods > lead or copper AL.    until they no longer > lead and/or    until they no longer > lead and/or
[cir] Contains provisions to sample    copper AL for two consecutive 6-      copper AL for two consecutive 6-
 at reduced number of sites in         month monitoring periods.             month monitoring periods.
 distribution system less frequency   [cir] To qualify for reduced WQP      [cir] To qualify for reduced WQP
 for all systems meeting their         distribution monitoring, P90 must     distribution monitoring, P90 must
 OWQPs.                                be <=10 [micro]g/L and the system     be <=10 [micro]g/L and the system
                                       must meet its OWQPs.                  must meet its OWQPs.
Sanitary Survey Review:               Sanitary Survey Review:               Sanitary Survey Review:
[cir] Treatment must be reviewed      [cir] CCT and WQP data must be        [cir] CCT and WQP data must be
 during sanitary surveys; no           reviewed during sanitary surveys      reviewed during sanitary surveys
 specific requirement to assess CCT    against most recent CCT guidance      against most recent CCT guidance
 or WQPs.                              issued by EPA.                        issued by EPA.
Find-and-Fix: No required follow-up   Find-and-Fix: If individual tap       Find-and-Fix: If individual tap
 samples or additional actions if an   sample >15 [mu]g/L, systems must:     samples >15 [micro]g/L.
 individual sample exceeds 15 [mu]g/  [cir] Collect a follow-up sample at   [cir] Find-and-fix steps:
 L.                                    each location >15 [mu]g/L.           [cir] Collect tap sample at the same
                                      [cir] Conduct WQP monitoring at or     tap sample site within 30 days.
                                       near the site >15 [mu]g/L.           [cir] For LSL, collect any liter or
                                      [cir] Perform needed corrective        sample volume.
                                       action.                              [cir] If LSL is not present, collect
                                                                             1 liter first draw after
                                                                             stagnation.
                                                                            [cir] For systems with CCT.
                                                                            [cir] Conduct WQP monitoring at or
                                                                             near the site >15 [mu]g/L.
                                                                            [cir] Perform needed corrective
                                                                             action.
                                                                            [cir] Document customer refusal or
                                                                             nonresponse after 2 attempts.
                                                                            [cir] Provide information to local
                                                                             public health officials.
----------------------------------------------------------------------------------------------------------------
                                           LSL Inventory and LSLR Plan
----------------------------------------------------------------------------------------------------------------
Initial LSL Program Activities:       Initial LSL Program Activities:       Initial LSL Program Activities:
[cir] Systems were required to        [cir] All systems must develop an     [cir] All systems must develop an
 complete a materials evaluation by    LSL inventory or demonstrate          LSL inventory or demonstrate
 the time of initial sampling. No      absence of LSLs within first 3        absence of LSLs within 3 years of
 requirement to update materials       years of final rule publication.      final rule publication.
 evaluation.                          [cir] LSL inventory must be updated   [cir] LSL inventory must be updated
[cir] No LSLR plan is required.        annually.                             annually or triennially, based on
                                      [cir] All systems with known or        their tap sampling frequency.
                                       possible LSLs must develop an LSLR   [cir] All systems with known or
                                       plan.                                 possible LSLs must develop an LSLR
                                                                             plan.
LSLR:                                 LSLR:                                 LSLR:
[cir] Systems with LSLs with P90 >15  [cir] Rule specifies replacement      [cir] Rule specifies replacement
 [micro]g/L after CCT installation     programs based on P90 level for       programs based on P90 level for
 must annually replace >=7% of         CWSs serving >10,000 people:          CWSs serving >3,300 people:
 number of LSLs in their              [cir] If P90 >15 [micro]g/L: Must     [cir] If P90 >15 [micro]g/L: Must
 distribution system when the lead     fully replace 3% of LSLs per year     fully replace 3% of LSLs per year
 action level is first exceeded.       (mandatory replacement) for 4         based upon a 2 year rolling average
[cir] Systems must replace the LSL     consecutive 6-month monitoring        (mandatory replacement) for at
 portion they own and offer to         periods.                              least 4 consecutive 6-month
 replace the private portion at the   [cir] If P90 >10 to 15 [micro]g/L:     monitoring periods.
 owner's expense.                      Implement an LSLR program with       [cir] If P90 >10 to 15 [micro]g/L:
[cir] Full LSLR, partial LSLR, and     replacement goals in consultation     Implement an LSLR program with
 LSLs with lead sample results <=15    with the primacy agency for 2         replacement goals in consultation
 [micro]g/L (``test-outs'') count      consecutive 1-year monitoring         with the primacy agency for 2
 toward the 7% replacement rate.       periods.                              consecutive 1-year monitoring
[cir] Systems can discontinue LSLR    [cir] Small CWSs and NTNCWSs that      periods.
 after 2 consecutive 6-month           select LSLR as their compliance      [cir] Small CWSs and NTNCWSs that
 monitoring periods <= lead AL.        option must complete LSLR within 15   select LSLR as their compliance
                                       years if P90 >15 [micro]g/L See       option must complete LSLR within 15
                                       Small System Flexibility.             years if P90 >15 [micro]g/L See
                                      [cir] Annual LSLR rate is based on     Small System Flexibility.
                                       number of LSLs when the system       [cir] Annual LSLR rate is based on
                                       first exceeds the action level plus   number of LSLs and galvanized
                                       the current number of lead status     requiring replacement when the
                                       unknown service lines.                system first exceeds the action
                                      [cir] Only full LSLR (both customer-   level plus the current number of
                                       owned and system-owned portion)       lead status unknown service lines.
                                       count toward mandatory rate or goal- [cir] Only full LSLR (both customer-
                                       based rate.                           owned and system-owned portion)
                                                                             count toward mandatory rate or goal-
                                                                             based rate.

                                         [cir] All systems must replace        [cir] All systems replace their
                                          their portion of an LSL if            portion of an LSL if notified by
                                          notified by consumer of private       consumer of private side
                                          side replacement within 45 days       replacement within 45 days of
                                          of notification of the private        notification of the private
                                          replacement.                          replacement. If the system
                                      [cir] Following each LSLR, systems        cannot replace the system's
                                       must:                                    portion within 45 days, it must
                                      [cir] Provide pitcher filters/            notify the state and replace the
                                       cartridges to each customer for 3        system's portion within 180
                                       months after replacement. Must be        days.
                                       provided within 24 hours for full    [cir] Following each LSLR, systems
                                       and partial LSLRs.                    must:
                                      [cir] Collect a lead tap sample at    [cir] Provide pitcher filters/
                                       locations served by replaced line     cartridges to each customer for 6
                                       within 3 to 6 months after            months after replacement. Provide
                                       replacement.                          pitcher filters/cartridges within
                                      [cir] Requires replacement of          24 hours for full and partial
                                       galvanized service lines that are     LSLRs.
                                       or ever were downstream of an LSL.   [cir] Collect a lead tap sample at
                                                                             locations served by replaced line
                                                                             within 3 to 6 months after
                                                                             replacement.
                                                                            [cir] Requires replacement of
                                                                             galvanized service lines that are
                                                                             or ever were downstream of an LSL.
LSL-Related Outreach:                 LSL-Related Outreach:                 LSL-Related Outreach:
[cir] When water system plans to      [cir] Inform consumers annually that  [cir] Inform consumers annually that
 replace the portion it owns, it       they are served by LSL or service     they are served by LSL or lead
 must offer to replace customer-       line of unknown lead status.          status unknown service line.
 owned portion at owner's expense.    [cir] Systems subject to goal-based   [cir] Systems subject to goal-based
[cir] If system replaces its portion   program must:                         program must:
 only:                                [cir] Conduct targeted outreach that  [cir] Conduct targeted outreach that
[cir] Provide notification to          encourages consumers with LSLs to     encourages consumers with LSLs to
 affected residences within 45 days    participate in the LSLR program.      participate in the LSLR program.
 prior to replacement on possible     [cir] Conduct an additional outreach  [cir] Conduct an additional outreach
 elevated short-term lead levels and   activity if they fail to meet their   activity if they fail to meet their
 measures to minimize exposure.        goal.                                 goal.
                                      [cir] Systems subject to mandatory    [cir] Systems subject to mandatory
                                       LSLR include information on LSLR      LSLR include information on LSLR
                                       program in public education (PE)      program in public education (PE)
                                       materials that are provided in        materials that are provided in
                                       response to P90 > AL.                 response to P90 > AL.
     [cir] Include offer to collect
      lead tap sample within 72
      hours of replacement.
     [cir] Provide test results
      within 3 business days after
      receiving results.
----------------------------------------------------------------------------------------------------------------
                                            Small System Flexibility
----------------------------------------------------------------------------------------------------------------
No provisions for systems to elect    Allows CWSs serving <=10,000 people   Allows CWSs serving <=10,000 people
 an alternative treatment approach     and all NTNCWSs with P90 >10          and all NTNCWSs with P90 >10
 but sets specific requirements for    [micro]g/L to elect their approach    [micro]g/L to select their approach
 CCT and LSLR.                         to address lead with primacy agency   to address lead with primacy agency
                                       approval:                             approval:
                                      [cir] Systems can choose CCT, LSLR,   [cir] Systems can choose CCT, LSLR,
                                       or provision and maintenance of       provision and maintenance of point-
                                       point-of-use devices.                 of-use devices; or replace all lead-
                                      [cir] NTNCWSs can also elect to        bearing plumbing materials.
                                       replace all lead-bearing materials.
----------------------------------------------------------------------------------------------------------------
                                          Public Education and Outreach
----------------------------------------------------------------------------------------------------------------
[cir] All CWSs must provide           [cir] CWSs must provide updated       [cir] CWSs must provide updated
 education material in the annual      health effects language in all PE     health effects language in all PE
 Consumer Confidence Report (CCR).     materials and the CCR.                materials and the CCR.
[cir] Systems with P90 >AL must       [cir] If P90 > AL:                    [cir] Customers can contact the CWS
 provide PE to customers about lead   [cir] Current PE requirements apply.   to get PE materials translated in
 sources, health effects, measures    [cir] Systems must notify consumers    other languages.
 to reduce lead exposure, and          of P90 > AL within 24 hours.         [cir] All CWSs are required to
 additional information sources.      [cir] In addition, CWSs must:          include information on how to
[cir] Systems must provide lead       [cir] Improve public access to lead    access the LSL inventory and how to
 consumer notice to individuals        information including LSL locations   access the results of all tap
 served at tested taps within 30       and respond to requests for LSL       sampling in the CCR.
 days of learning results.             information.                         [cir] Revises the mandatory health
[cir] Customers can contact the CWS   [cir] Deliver notice and educational   effects language to improve
 to get PE materials translated in     materials to consumers during water-  accuracy and clarity.
 other languages.                      related work that could disturb      [cir] If P90 > AL:
                                       LSLs.                                [cir] Current PE requirements apply.
                                      [cir] Provide increased information   [cir] Systems must notify consumers
                                       to local and state health agencies.   of P90 > AL within 24 hours.
                                      [cir] Provide lead consumer notice    [cir] In addition, CWSs must:
                                       to consumers whose individual tap    [cir] Deliver notice and educational
                                       sample is >15 [micro]g/L within 24    materials to consumers during water-
                                       hours.                                related work that could disturb
                                      [cir] Also see LSL-Related Outreach    LSLs.
                                       in LSLR section of table.            [cir] Provide information to local
                                                                             and state health agencies.
                                                                            [cir] Provide lead consumer notice
                                                                             to consumers whose individual tap
                                                                             sample is >15 [micro]g/L as soon as
                                                                             practicable but no later than 3
                                                                             days.
                                                                            Also see LSL-Related Outreach
                                                                             section of table.
----------------------------------------------------------------------------------------------------------------
                                          Change in Source or Treatment
----------------------------------------------------------------------------------------------------------------
Systems on a reduced tap monitoring   Systems on any tap monitoring         Systems on any tap monitoring
 schedule must obtain prior primacy    schedule must obtain prior primacy    schedule must obtain prior primacy
 agency approval before changing       agency approval before changing       agency approval before changing
 their source or treatment.            their source or treatment.            their source or treatment. These
                                                                             systems must also conduct tap
                                                                             monitoring biannually.
----------------------------------------------------------------------------------------------------------------

                                      Source Water Monitoring and Treatment
----------------------------------------------------------------------------------------------------------------
[cir] Periodic source water           [cir] Primacy Agencies can waive      [cir] Primacy Agencies can waive
 monitoring is required for systems    continued source water monitoring     continued source water monitoring
 with:                                 if the:                               if the:
[cir] Source water treatment; or      [cir] System has already conducted    [cir] System has already conducted
[cir] P90 > AL and no source water     source water monitoring for a         source water monitoring for a
 treatment.                            previous P90 > AL;                    previous P90 > AL;
                                      [cir] primacy agency has determined   [cir] primacy agency has determined
                                       that source water treatment is not    that source water treatment is not
                                       required; and                         required; and
                                      [cir] System has not added any new    [cir] System has not added any new
                                       water sources.                        water sources.
----------------------------------------------------------------------------------------------------------------
                           Lead in Drinking Water at Schools and Child Care Facilities
----------------------------------------------------------------------------------------------------------------
[cir] Does not include separate       [cir] CWSs must conduct lead in       [cir] CWS must conduct sampling at
 testing and education program for     drinking water testing and PE at      20% of elementary schools and 20%
 CWSs at schools and child care        20% of K-12 schools and licensed      of child care facilities per year
 facilities.                           child cares in service area every 5   and conduct sampling at secondary
[cir] Schools and child cares that     years.                                schools on request for 1 testing
 are classified as NTNCWSs must       [cir] Sample results and PE must be    cycle (5 years) and conduct
 sample for lead and copper.           provided to each sampled school/      sampling on request of all schools
                                       child care, primacy agency and        and child care facilities
                                       local or state health department.     thereafter.
                                      [cir] Excludes facilities built       [cir] Sample results and PE must be
                                       after January 1, 2014.                provided to each sampled school/
                                                                             child care, primacy agency and
                                                                             local or state health department.
                                                                            [cir] Excludes facilities built or
                                                                             replaced all plumbing after January
                                                                             1, 2014.
----------------------------------------------------------------------------------------------------------------
                                            Primacy Agency Reporting
----------------------------------------------------------------------------------------------------------------
Primacy Agencies must report          Expands current requirements to       Expands current requirements to
 information to EPA that includes      include:                              include:
 but is not limited to:               [cir] All P90 values for all system   [cir] All P90 values for all system
[cir] All P90 levels for systems       sizes.                                sizes.
 serving >3,300 people, and only      [cir] The current number of LSLs and  [cir] The current number of LSLs and
 levels >15 [micro]g/L for smaller     lead status unknown service lines     lead status unknown service lines
 systems.                              for every water system.               for every water system.
[cir] Systems that are required to    [cir] OCCT status of all systems      [cir] OCCT status of all systems
 initiate LSLR and the date            including primacy agency-specified    including primacy agency-specified
 replacement must begin.               OWQPs.                                OWQPs.
[cir] Systems for which optimal
 corrosion control treatment (OCCT)
 has been designated.
----------------------------------------------------------------------------------------------------------------

B. Does this action apply to me?

    Entities that could potentially be affected include the following:

------------------------------------------------------------------------
                                      Examples of potentially affected
             Category                             entities
------------------------------------------------------------------------
Public water systems..............  Community water systems (a public
                                     water system that (A) serves at
                                     least 15 service connections used
                                     by year-round residents of the area
                                     served by the system; or (B)
                                     regularly serves at least 25 year-
                                     round residents).
                                    Non-transient, non-community water
                                     systems (a public water system that
                                     is not a community water system and
                                     that regularly serves at least 25
                                     of the same persons over 6 months
                                     per year).
State and tribal agencies.........  Agencies responsible for drinking
                                     water regulatory development and
                                     enforcement.
------------------------------------------------------------------------

    This table is not intended to be exhaustive, but rather provides a
guide for readers regarding entities that could be affected by this
action. To determine whether your facility or activities could be
affected by this action, you should carefully examine this final rule.
    As part of this document for the LCRR, ``state'' refers to the
agency of the state or tribal government which has jurisdiction over
public water systems consistent with the definition of ``state'' in 40
CFR 141.2. During any period when a state or tribal government does not
have primary enforcement responsibility pursuant to section 1413 of the
SDWA, the term ``state'' means the applicable Regional Administrator of
the U.S. Environmental Protection Agency. If you have questions
regarding the applicability of this action to a particular entity,
consult the person listed in the FOR FURTHER INFORMATION CONTACT
section.

II. Background

A. Health Effects of Lead and Copper

    Exposure to lead is known to present serious health risks to the
brain and nervous system of children. Lead exposure causes damage to
the brain and kidneys and can interfere with the production of red
blood cells that carry oxygen to all parts of the body. Lead has acute
and chronic impacts on the body. The most robustly studied and most
susceptible subpopulations are the developing fetus, infants, and young
children. Even low level lead exposure is of particular concern to
children because their growing bodies absorb more lead than adults do,
and their brains and nervous systems are more sensitive to the damaging
effects of lead. EPA estimates that drinking water can make up 20
percent or more of a person's total exposure to lead. Infants who
consume mostly formula mixed with tap water can, depending on the level
of lead in the system and other sources of lead in the home, receive 40
percent to 60 percent of their exposure to lead from drinking water
used in the formula (USEPA, 1988). Scientists have linked lead's
effects on the brain with lowered intelligence quotient (IQ) and
attention disorders in children (USEPA, 2013). Young children and
infants are particularly vulnerable to lead because the physical and
behavioral effects of lead occur at lower exposure levels in children
than in adults. During

pregnancy, lead exposure may affect prenatal brain development. Lead is
stored in the bones and it can be released later in life. Even at low
levels of lead in blood, there is an increased risk of health effects
in children (e.g., less than 5 micrograms per deciliter) and adults
(e.g., less than 10 micrograms per deciliter) (National Toxicology
Program, 2012).
    The 2013 Integrated Science Assessment for Lead (USEPA, 2013) and
the HHS National Toxicology Program Monograph on Health Effects of Low-
Level Lead (National Toxicology Program, 2012) have both documented the
association between lead and adverse cardiovascular effects, renal
effects, reproductive effects, immunological effects, neurological
effects, and cancer. EPA's Integrated Risk Information System (IRIS)
Chemical Assessment Summary provides additional health effects
information on lead (USEPA, 2004a). For a more detailed explanation of
the health effects associated with lead for children and adults see
Appendix D of the Economic Analysis.
    Acute copper exposure causes gastrointestinal distress. Chronic
exposure to copper is particularly a concern for people with Wilson's
disease because they are prone to copper accumulation in body tissue,
which can lead to liver damage, neurological, and/or psychiatric
symptoms. For a more detailed explanation of the health effects
associated with copper see Appendix E of the final rule Economic
Analysis (USEPA, 2020). EPA did not propose revisions to the copper
requirements; thus, the final rule does not revise the copper
requirements.

B. Statutory Authority

    EPA is publishing revisions to the LCR under the authority of the
Safe Drinking Water Act (SDWA), including sections 1412, 1413, 1414,
1417, 1445, and 1450 of the SDWA. 42 U.S.C. 300f et seq.
    Section 1412(b)(9) provides that ``[T]he Administrator shall, not
less often than every 6 years, review and revise, as appropriate, each
national primary drinking water regulation promulgated under this
subchapter. Any revision of a national primary drinking water
regulation shall be promulgated in accordance with this section, except
that each revision shall maintain, or provide for greater, protection
of the health of persons.'' 42 U.S.C. 300g-1(b)(9). In promulgating
this revised NPDWR, EPA followed the applicable procedures and
requirements described in section 1412 of the SDWA, including those
related to (1) the use of the best available, peer-reviewed science and
supporting studies; (2) presentation of information on public health
effects; and (3) a health risk reduction and cost analysis of the rule
in 1412(b)((3)(A), (B), (C) of the SDWA, 42 U.S.C. 300g-1(b)(3)(A)-(C).
    This rule revises the Lead and Copper Rule which established
treatment technique requirements instead of a maximum contaminant
level. Section 1412(b)(7)(A) of the SDWA authorizes EPA to ``promulgate
a national primary drinking water regulation that requires the use of a
treatment technique in lieu of establishing a maximum contaminant
level, if the Administrator makes a finding that it is not economically
or technologically feasible to ascertain the level of the
contaminant.'' EPA's decision to promulgate a treatment technique rule
for lead instead of a maximum contaminant level (MCL) in 1991 has been
upheld by the United States Court of Appeals for the District of
Columbia Circuit. American Water Works Association v. EPA, 40 F.3d
1266, 1270-71 (D.C. Cir. 1994).
    In establishing treatment technique requirements, the Administrator
is required to identify those treatment techniques ``which in the
Administrator's judgment, would prevent known or anticipated adverse
effects on the health of persons to the extent feasible.'' 42 U.S.C.
300g-1(b)(7)(A). ``Feasible'' is defined in Section 1412(b)(4)(D) of
the SDWA as ``feasible with the use of the best technology, treatment
techniques and other means which the Administrator finds after
examination for efficacy under field conditions and not solely under
laboratory conditions, are available (taking cost into
consideration).'' The legislative history for this provision makes it
clear that ``feasibility'' is to be defined relative to ``what may
reasonably be afforded by large metropolitan or regional public water
systems.'' A Legislative History of the Safe Drinking Water Act,
Committee Print, 97th Cong., 2d Sess. (1982) at 550. See also City of
Portland v. EPA, 507 F.3d 706 (D.C. Cir. 2007) (upholding EPA's
treatment technique for Cryptosporidium and the Agency's interpretation
that ``feasible'' means technically possible and affordable, rather
than a cost/benefit determination). If the ``feasible'' treatment
technique requirement would result in an increase in the health risk
from drinking water by increasing the concentration of other
contaminants in drinking water, or interfering with the efficacy of
treatment techniques or processes that are used to comply with other
national primary drinking water regulations, then the treatment
techniques ``shall minimize the overall risk of adverse health effects
by balancing the risk from the contaminant and the risk from other
contaminants''; however, the resulting requirements may not be more
stringent than what is ``feasible''. 42 U.S.C. 300g-1(b)(5).
    Section 1414(c) of the SDWA, as amended by the WIIN Act, requires
public water systems to provide notice to the public if the water
system exceeds the lead action level. 42 U.S.C. 300g-3(c). The SDWA
section 1414(c)(2) provides that the Administrator ``shall, by
regulation . . . prescribe the manner, frequency, form, and content for
giving notice'' under section 1414(c). 42 U.S.C. 300g-3(c)(2). The SDWA
section 1414(c)(2)(C) specifies additional requirements for those
regulations related to public notification of a lead action level
exceedance ``that has the potential to have serious adverse effects on
human health as a result of short-term exposure.'' The public notice
must be distributed as soon as practicable, but not later than 24 hours
after the water systems learns of the action level exceedance and the
system must report the exceedance to both the Administrator and the
primacy agency in that same time period. 42 U.S.C. 300g-3(c)(2)(C)(i)
and (iii). The requirement in Section 1414(c)(2)(C)(iii) to provide
notification to EPA as well as the primacy agency was enacted in 2016
as part of the WIIN Act. One purpose of this requirement is to allow
EPA to implement Section 1414(c)(2)(D), which was also enacted as part
of the WIIN Act. It directs EPA to issue the required public notice for
an exceedance of the lead action level, not later than 24 hours after
the Administrator is notified of the exceedance, if the water system or
the primacy agency has not issued the required public notice. EPA may
receive this information directly from water systems or states. Because
the Administrator's duty under Section 1414(c)(2)(D) is triggered only
in the event of an action level exceedance and not any violation of an
NPDWR, EPA interprets 1414(c)(2)(C)(iii) to require systems to report
only action level exceedances (ALEs) to the Administrator.
    Section 1417(a)(2) of the SDWA provides that public water systems
``shall identify and provide notice to persons that may be affected by
lead contamination of their drinking water where such contamination
results from the lead content of the construction materials of the
public water distribution system and/or corrosivity of the water supply
sufficient to cause

leaching of lead. 42 U.S.C. 300g-6(a)(2)(A)(i) and (ii). The notice
``shall be provided notwithstanding the absence of a violation of any
national drinking water standard.'' 42 U.S.C. 300g-6(a)(2)(A).
    Section 1445(a) of the SDWA authorizes the Administrator to
establish monitoring, recordkeeping, and reporting regulations, to
assist the Administrator in establishing regulations under the SDWA, in
determining compliance with the SDWA, and in administering any program
of financial assistance under the SDWA. 42 U.S.C. 300j-4(a). In
requiring a public water system to monitor under section 1445(a) of the
SDWA, the Administrator may take into consideration the water system
size and the contaminants likely to be found in the system's drinking
water. 42 U.S.C. 300j-4(a). The SDWA section 1445(a)(1)(C) provides
that ``every person who is subject to a national primary drinking water
regulation'' must provide such information as the Administrator may
reasonably require to assist the Administrator in establishing
regulations under section 1412. 42 U.S.C 300j-4(a)(1)(C). The
monitoring, recordkeeping, and reporting requirements in today's rule,
including the inventory requirements, are part of the NPDWR treatment
technique requirements; in addition, EPA expects to consider the
information collected in any future revisions to the Lead and Copper
Rule and in administering financial assistance programs (e.g., grant
programs for the replacement of LSLs and/or school sampling).
    Under section 1413(a)(1) of the SDWA a state may exercise primary
enforcement responsibility (``primacy'') for NPDWRs when EPA has
determined, among other things, that the state has adopted regulations
that are no less stringent than EPA's. 42 U.S.C. 300g-2(a)(1). To
obtain primacy for this rule, states must adopt regulations that are at
least as stringent as this rule within two years of EPA's promulgation,
unless EPA grants the state a two-year extension. State primacy
requires, among other things, adequate enforcement (including
monitoring and inspections) and reporting requirements. EPA must
approve or deny state primacy applications within 90 days of submission
to EPA. 42 U.S.C. 300g-2(b)(2). In some cases, a state submitting
revisions to adopt an NPDWR has interim primary enforcement authority
for the new regulation while EPA's decision on the revision is pending.
42 U.S.C. 300g-2(c). Section 1413(b)(1) of the SDWA requires EPA to
establish regulations governing the primacy application and review
process ``with such modifications as the Administrator deems
appropriate.'' In addition to the LCR revisions promulgated today which
are more stringent than the previous LCR, this rule includes changes to
primacy requirements related to this rule.
    Section 1450 of the SDWA authorizes the Administrator to prescribe
such regulations as are necessary or appropriate to carry out his or
her functions under the Act. 42 U.S.C. 300j-9.

C. Regulatory History

    EPA published the LCR on June 7, 1991, to control lead and copper
in drinking water at the consumer's tap. The rule established a NPDWR
for lead and copper consisting of treatment technique requirements that
include CCT, source water treatment, lead service line replacement
(LSLR), and PE. The rule established an action level of 0.015 mg/L or
15 [micro]g/L for lead and 1.3 mg/L or 1,300 [micro]g/L for copper. The
action level is a concentration of lead or copper in the water that
determines, in some cases, whether a water system must install CCT,
monitor source water, replace LSLs, and undertake a PE program. The
action level is exceeded if the concentration in more than 10 percent
of tap samples collected during any monitoring period is greater than
the action level (i.e., if the 90th percentile level is greater than
the action level). If the 90th percentile value for tap samples is
above the action level, it is not a treatment technique violation, but
rather compels actions, such as WQP monitoring, CCT, source water
monitoring/treatment, PE, and LSLR. Failure to take these actions
results in the water system being in violation of the treatment
technique or monitoring and reporting requirements.
    In 2000, EPA promulgated the Lead and Copper Rule Minor Revisions
or LCRMR, which streamlined requirements, promoted consistent national
implementation, and in many cases, reduced burden for water systems.
One of the provisions of the LCRMR required states to report the lead
90th percentile to EPA's Safe Drinking Water Information System (SDWIS)
database for all water systems serving greater than 3,300 persons.
States must report the lead 90th percentile value for water systems
serving 3,300 or fewer persons only if the water system exceeds the
action level. The new reporting requirements became effective in 2002.
In 2004, EPA published minor corrections to the LCR to reinstate text
that was inadvertently dropped from the rule during the previous
revision.
    In 2004, EPA undertook a national review of the LCR and performed a
number of activities to help identify needed actions to improve
implementation of the LCR. EPA collected and analyzed lead
concentration data and other information required by the LCR, carried
out review of implementation by states, held four expert workshops to
further discuss elements of the LCR, and worked to better understand
local and state efforts to test for lead in school drinking water,
including a national meeting to discuss challenges and needs. EPA used
the information collected during the national review to identify needed
short-term and long-term regulatory revisions to the LCR.
    In 2007, EPA promulgated a set of short-term regulatory revisions
and clarifications to strengthen implementation of the LCR in the areas
of monitoring, treatment, customer awareness, LSLR, and improve
compliance with the PE requirements to ensure drinking water consumers
receive meaningful, timely, and useful information needed to help them
limit their exposure to lead in drinking water. Long-term issues,
requiring additional research and input, were identified for a
subsequent set of rule revisions.
    EPA published proposed revisions to the LCR on November 13, 2019
for public review and comment (84 FR 61684). The proposal included
provisions to strengthen procedures and requirements related to health
protection and the implementation of the existing LCR in the following
areas: Lead tap sampling; corrosion control treatment; LSL replacement;
consumer awareness; and public education. In addition, the proposal
included new requirements for CWSs to conduct lead in drinking water
testing and public education in schools and child care facilities.

III. Revisions to 40 CFR Part 141, Subpart I, Control of Lead and
Copper

A. Lead Trigger Level

1. Proposed Revisions
    EPA proposed a lead ``trigger level'' of 10 [micro]g/L in addition
to the LCR's current 15 [micro]g/L lead action level. The trigger level
is not a health based standard. EPA proposed 10 [micro]g/L as a
reasonable concentration that is below the action level and above the
Practical Quantitation Level of 5 [micro]g/L at which to require water
systems to take a progressive set of actions to reduce lead levels
prior to an action level exceedance and to have a plan in place

to rapidly respond if there is an action level exceedance. For large
and medium water systems, EPA proposed action that included optimizing
CCT, a goal based LSLR program, and annual tap sampling (no reduced
monitoring). EPA proposed that small water systems would be required to
designate the actions they would take if they exceed the action level.
2. Public Comment and EPA's Response
    A number of commenters supported the trigger level, stating that it
would be beneficial because it initiates actions by public water
systems to decrease their lead levels and requires the utility to take
proactive steps to remove lead from the distribution system, reducing
exposure to lead from drinking water throughout the utility's
community. A commenter suggested that the trigger level be lowered to 5
[micro]g/L (the stakeholder added a reference to ``CDC'' however, the
Centers for Disease Control and Prevention established a blood lead
reference level of 5 [micro]g/deciliter, that is not a drinking water
level). Other commenters suggested a trigger level of 1 [micro]g/L
(recommended by the American Academy of Pediatrics (AAP, 2016)).
    The use of a trigger level of 10 [micro]g/L in the implementation
of this treatment technique rule provides a reasonable concentration
that is below the action level and above the Practical Quantitation
Level of 5 [micro]g/L at which to require water systems to take a
progressive set of actions to reduce lead levels prior to an action
level exceedance and to have a plan in place to rapidly respond if
there is an action level exceedance. Requiring such actions of systems
only when a trigger level 10 [micro]g/L is exceeded, rather than all
systems prioritizes actions at systems with higher lead levels and
allows states to work proactively with water systems that are a higher
priority. The actions water systems will be required to undertake if
their 90th percentile exceeds the trigger level will require review and
oversight from states to assure that they are effective in reducing
drinking water lead levels. As shown in Exhibits 4-13 and 4-20 of the
Economic Analysis, setting a lower trigger level would substantially
increase the number of water systems required to obtain review and
input from their primacy agency to comply with the CCT and LSLR
requirements. EPA has concluded it is not practicable for this
significant number of water systems to obtain this state review and
approval.
    The LCR's action level prioritizes systems with the highest lead
levels for state interaction and mandates actions to reduce drinking
water lead levels. Similarly, the Agency has determined that 10
[micro]g/L is a reasonable level to trigger water systems with higher
(but not the highest) lead levels to have interactions with states to
prepare for and to undertake actions to reduce drinking water lead
levels.
    Other commenters expressed concerns about the potential for
confusion caused by separate trigger level and action level
requirements. One of these commenters stated that the trigger level
would be another decision-criterion for the public to mis-construe as a
level of health concern. EPA does not agree with these commenters. The
Agency has established a health based maximum contaminant level goal
(MCLG) of zero for lead. The trigger level is not a health based level,
rather it is a reasonable level at which to require systems to begin to
take a progressive set of actions based upon lead levels at the tap
that are appropriate to assure reduced exposure to lead. The concept of
including additional thresholds to compel actions before an action
level exceedance was suggested by the Association of State Drinking
Water Administrators as a way to focus actions towards the systems with
the greatest potential concerns (USEPA, 2018). This regulatory
framework is similar to other NPDWRs, such as the Long-Term 2 Enhanced
Surface Water Treatment Rule (LT2ESWTR), which requires increasing
levels of remedial action based on the concentration of the
contaminant. EPA has revised the regulatory text in the final rule to
improve its clarity and will work with primacy agencies and water
systems to assure they understand the different actions that must be
taken when systems exceed the trigger level or action level.
    Additional commenters suggested EPA lower the action level and
eliminate the trigger level, stating the trigger level makes the rule
unnecessarily complicated and needlessly adds to the regulatory burden.
EPA disagrees that the action level should be lowered. EPA established
the lead action level in 1991 to require small and medium-sized systems
exceeding it to install corrosion control treatment and to require
large systems and other systems with optimal corrosion control
treatment (OCCT) to conduct LSLR. The action level was based on
examination of data at 39 medium sized systems; while it was ``limited
as a basis for making broad-based estimates of treatment efficacy,''
EPA concluded that ``the data are useful as general indictors of the
range of levels systems have achieved with various treatment measures
in place.'' (56 FR 26490). EPA acknowledged in 1991 that the selection
of the action level ``is not based on a precise statistical analysis of
the effectiveness of treatment'' but it ``reflects EPA's assessment of
a level that is generally representative of effective corrosion control
treatment, and that is, therefore, useful as a tool for simplifying the
implementation of the treatment technique'' at those systems. (56 FR
26490). EPA decided to use the same action level as a screen to
determine which systems with CCT must also replace LSLs (56 FR 26491).
While EPA is not lowering the action level, the Agency is strengthening
the public health protections of the treatment technique by improving
the sampling procedures to better identify elevated levels of lead.
This will result in more systems exceeding the action level and more
actions to reduce drinking water exposure to lead.
    EPA disagrees with commenters that the trigger level results in
unnecessary complexity and regulatory burden. While there is burden
associated with the actions that systems must take when they exceed the
trigger level, EPA determined that a progressive set of actions based
upon lead levels at the tap are feasible to assure reduced exposure to
lead. EPA in its Health Risk Reduction Cost Analysis (HRRCA) has found
that a significant number of benefits accrue from systems being
required to take mitigation activities as a result of trigger level
exceedances. EPA also examined the costs and found that it is feasible
for systems to take the actions required when there is a trigger level
exceedance. Requiring these actions when a system's lead levels are
high, but not exceeding the action level, will help both systems and
states to engage in a manageable and orderly process to reduce lead
levels in drinking water so that they remain below the lead action
level. Accordingly, inclusion of the trigger level in the final rule
will provide for ``greater protection of the health of persons''
consistent with the statutory authority in Section 1412(b)(9) of the
Safe Drinking Water Act (SDWA) for revising existing drinking water
standards. Additionally, this proactive approach to lead contamination
in response to a trigger level will allow systems to quickly take
action if there is a ALE, while reducing the likelihood that a water
system will exceed the action level in the future or be faced with the
need to implement emergency measures such as the distribution of water
filters or bottled water in response to a lead crisis.

3. Final Revisions
    EPA is finalizing the lead trigger level of 10 [micro]g/L and
maintaining the lead action level of 15 [micro]g/L. In the event of a
trigger level exceedance, the actions water systems are required to
take vary based on characteristics of the system. Each of the
requirements brought about by a trigger level exceedance is discussed
in detail elsewhere in this document. However, in summary, small CWSs
serving populations of 10,000 or fewer persons and all sizes of NTNCWS
that exceed the lead trigger level, but not the lead action level, must
evaluate the small system flexibilities described in Section III.E of
this preamble and identify the action they will take if they exceed the
action level. Medium and large CWSs that exceed the trigger level, but
do not exceed the action level, must implement requirements based on
their CCT and LSL status as described below.
    Water systems with CCT in place and with no LSLs or service lines
of unknown lead status are required to re-optimize CCT (see Section
III.B); and conduct annual tap sampling (no reduced monitoring (see
Section III.G)).
    Water systems without CCT in place and with no LSLs or service
lines of unknown lead status are required to: conduct a CCT study and
obtain state approval for designated CCT (see Section III.B.); and
conduct annual tap sampling (no reduced monitoring (see Section
III.G)).
    Water systems with CCT in place and with LSLs or service lines of
unknown lead status are required to: Re-optimize CCT (see Section
III.B); notify customers with LSLs or unknowns (see Section III.F);
implement a goal-based LSLR program (see Section III.D); and conduct
annual tap sampling (no reduced monitoring (see Section III.G)).
    Water systems without CCT in place and with LSLs or service lines
(i.e., the pipe that connects the water main to the building) of
unknown lead status are required to: Conduct a CCT study and obtain
state approval for designated CCT (see Section III.B) notify customers
with an LSL or unknowns (see Section III.F); implement a goal based
LSLR program (see Section III.D); and conduct annual tap sampling (no
reduced monitoring (see Section III.G).

B. Corrosion Control Treatment Requirements Based on Lead 90th
Percentile

1. Proposed Revisions
    EPA proposed revised CCT requirements based on the water system's
lead 90th percentile level and CCT status. The proposed rule required
all water systems with CCT that have a lead trigger level exceedance
(>10 [mu]g/L but <=15 [mu]g/L) or a lead action level exceedance (>15
[mu]g/L) to re-optimize their CCT. The proposed rule would require
water systems to evaluate other corrosion control treatments, make a
re-optimization recommendation, and receive state approval of any
changes to CCT or water quality parameters (WQPs). The state could
require the water system to conduct a CCT study under the proposed
rule.
    The proposal required water systems without CCT that exceed the
lead trigger level (10 [micro]g/L) to conduct a CCT study and make a
CCT recommendation to the state. Once approved by the state, the CCT
recommendation would be implemented if the water system exceeds the
lead action level in subsequent tap sampling. Water systems without CCT
that have previously conducted a CCT study and made CCT recommendations
would not be required to prepare a new CCT study if they exceed the
trigger level again unless the state determines that a new study is
required due to changed circumstances, such as addition of a new water
source or changes in treatment or if revised CCT guidance has been
issued by EPA since the study was conducted. Under the proposed rule
the state could also determine that a new CCT study is needed due to
other significant information becoming available.
    EPA proposed changes to the CCT options that water systems must
consider and the methods by which water systems would evaluate those
options. EPA proposed removing calcium carbonate stabilization as a CCT
option. EPA also proposed requiring water systems to evaluate two
additional options for orthophosphate-based corrosion control:
Maintaining a 1 mg/L orthophosphate residual concentration and
maintaining a 3 mg/L orthophosphate residual concentration.
    EPA also proposed changes to the methodologies by which systems
evaluate CCT options. EPA proposed that metal coupon tests could only
be used as a screen to reduce the number of options that are evaluated
using pipe rig/loops and would no longer be able to be used as the
basis for determining the OCCT.
    EPA proposed that when systems choose to conduct coupon studies to
screen potential options and/or pipe rig/loop studies, these systems
cannot exclude a treatment option from the study based upon potential
effects on other water quality treatment processes. Systems that are
conducting coupon screening studies and/or pipe loop/rig studies should
identify potential constraints, such as the impact that CCT options or
treatment chemicals may have on other water quality treatment
processes. Those impacts should be noted and considered as part of the
CCT study design.
    EPA proposed that a medium or small water system that exceeds the
lead action level (15 [micro]g/L), that has previously not exceeded the
lead trigger level and does not have CCT installed, would be required
to conduct a CCT study, make a treatment recommendation, and obtain
state approval of the OCCT determination. EPA proposed that systems be
required to complete these steps even if the system meets the lead
action level in two subsequent, consecutive 6-month monitoring periods
over the course of this process. Water systems that meet the action
level for two consecutive 6-month monitoring periods before installing
the state-approved treatment would be required to install that CCT upon
any subsequent action level exceedance. EPA proposed to retain the
current LCR provision that allows a state to waive the requirement for
a CCT study.
2. Public Comment and EPA's Response
    Commenters generally supported the evaluation or re-evaluation of
corrosion control treatment based on a trigger level or action level
exceedance because it would increase public health protection by
prioritizing systems with the highest 90th percentiles. Many commenters
had objections to the proposed re-optimization process. Some commented
that the re-optimization process was too prescriptive, and that more
flexibility was needed. Commenters wrote that the steps needed to
optimize or reoptimize treatment varied based on factors including the
presence/absence of LSLs, system size, 90th percentile lead
concentration, and existing corrosion control treatment. Several
commenters suggested a toolbox or ``bin approach'' that allows
consideration of these factors by systems and states to determine which
optimization/re-optimization process or ``bin'' is most appropriate.
For example, water systems with LSLs and OCCT would be in a different
``bin'' than water systems with LSLs and no OCCT. Many commenters
suggested that systems be allowed to modify the existing corrosion
control treatment before considering alternate treatments. Commenters
stated that the proposed re-optimization process might limit a system's
ability to quickly and efficiently reduce lead levels. EPA agrees that
optimization and re-optimization processes should

provide more flexibility. EPA agrees that for some systems, lead
reductions can be achieved quickly with slight modifications of the
existing CCT and should not be delayed potentially by two years for the
results of the corrosion control study. EPA agrees it is appropriate
for states to approve modifications of the system's existing CCT for
the ``bin'' of systems that are between the trigger level and action
level without a corrosion control study.
    EPA agrees that the process to optimize/reoptimize CCT should be
determined based on system characteristics such as system size, the
presence of LSLs and 90th percentile value. EPA agrees that a ``bin
approach'' in which the steps of the optimization/re-optimization
process depend upon system characteristics can provide flexibility for
some systems to more effectively establish optimal CCT. EPA agrees that
requirements to conduct harvested pipe loop studies and coupon studies
are best delineated through such a bin approach. Harvested pipe loop
studies are only required for systems with LSLs that exceed the lead
action level. To the extent that there are any large systems without
corrosion control treatment that have LSLs and exceed the lead
practical quantitation level of 0.005 mg/L, those systems would also
need to conduct a harvested pipe loop study. EPA believes that the CCT
changes needed for systems of any size above the action level merit a
thorough investigation of the impacts of the options on the existing
LSL pipe scale. Commenters noted that some small systems may not have
the technical capacity to construct and operate a harvested pipe loop
study. EPA notes that in these cases the final rule provides
flexibility to these small systems to implement a LSLR program or POU
program. Coupon studies can serve as a screen to reduce the number of
options for the harvested pipe loop study. Commenters noted that the
construction of harvested flow-through pipe loops and the stabilization
of those loops can take six months to one year before options can be
evaluated. EPA agrees that more time is needed to construct pipe loops
from harvested pipes and therefore is removing the requirement for
initial treatment recommendations in the final rule for large and
medium systems. For these systems, the final rule directs them to start
constructing and operating the flow-through pipe loops after the action
level exceedance in place of the initial treatment recommendation step,
since the pipe loop study will be the basis for their treatment
recommendation. Commenters indicated that for some systems, coupon
studies rather than pipe loop studies may be an appropriate treatment
recommendation tool. EPA agrees that coupon studies can be used for
systems that do not have LSLs. The final rule only requires harvested
pipe loop studies for systems that have LSLs.
    Many commenters had concerns with orthophosphate impacts on
wastewater treatment. The use of orthophosphate for corrosion control
can increase the phosphorus loading to wastewater treatment facilities.
However, water systems conducting corrosion control studies cannot rule
out orthophosphate simply based on the increase in loading to
wastewater treatment facilities. The definition of optimal corrosion
control treatment means the corrosion control treatment that minimizes
lead and copper concentrations at users' taps while ensuring that the
system does not violate any national primary drinking water
regulations. SDWA Section 1412(b)(7)(A) requires that a treatment
technique prevent known or anticipated adverse effects on the health of
persons to the extent feasible. EPA has determined that orthophosphate
treatment is a feasible corrosion control technology in accordance with
SDWA Section 1412(b)(4)(E). Therefore, eliminating orthophosphate as an
option because of concerns unrelated to compliance with national
primary drinking water regulations may prevent a system from installing
the treatment technique that reduces to the extent feasible the risks
of adverse health effects from lead in drinking water. In designing the
CCT studies, water systems should evaluate the orthophosphate treatment
options in the coupon screening and/or pipe loop/rig studies. EPA has
examined the potential costs of additional phosphorus usage on
wastewater treatment systems and has included this in the Economic
Analysis for the final rule. Many commenters objected to the required
evaluations of orthophosphate addition at 1 mg/L and 3 mg/L. Some
commenters characterized these as high orthophosphate doses. EPA
disagrees that these orthophosphate doses are too high to be considered
in the corrosion control study. The commenters may have assumed that
the dose was measured as P which would be three times greater than the
dose measured as PO4. EPA is clarifying that the
orthophosphate doses to be studied are measured as PO4. The
high-end dose in the corrosion control study of 3 mg/L as
PO4 is at the low end of the typical range used in the
United Kingdom where 95 percent of public water supplies are dosed with
orthophosphate (Hayes and Hydes, 2010). EPA also notes that the 2018
edition of Recommended Standards for Water Works published by the Great
Lakes--Upper Mississippi Board of State and Provincial Public Health
and Environmental Managers includes a requirement that total phosphate
not exceed 10 mg/L as phosphate sequestering iron and manganese, which
are aesthetic concerns and not a health concern. There are also
standards in the document for orthophosphate and blended phosphates for
corrosion control noting that the system shall have a chemical feed
system capable of maintaining an orthophosphate residual of at least
1.0 mg/L as P (3.0 mg/L as PO4) throughout the distribution
system. The member states for this document are Illinois, Indiana,
Iowa, Michigan, Minnesota, Missouri, New York, Ohio, Pennsylvania, and
Wisconsin (Great Lakes, 2018).
    Some commenters supported the elimination of calcium carbonate
stabilization as a corrosion control treatment alternative because they
agreed with EPA's rationale that it is not an effective CCT option, but
others did not, stating that it worked in some specific circumstances.
EPA does not agree that calcium carbonate stabilization should remain
as a CCT option. Based upon the available peer reviewed science, EPA
has determined that calcium carbonate stabilization treatment does not
form a consistent scale on lead and copper pipes to a level that makes
it effective as a CCT option (AwwaRF and DVGW-Technologiezentrum
Wasser, 1996; Schock and Lytle, 2011; Hill and Cantor, 2011).
Therefore, EPA has determined it is not appropriate to require water
systems to evaluate it as an option as part of a corrosion control
study. Some commenters noted that some water systems have already been
deemed optimized using this technique. EPA notes that states will still
have the authority to designate the necessary water quality parameters
to allow these systems to maintain this treatment as optimal corrosion
control unless the system exceeds the lead trigger level or action
level.
3. Final Rule Requirements
    EPA has included a provision in the final LCRR to identify ``bins''
of systems for specific corrosion control treatment optimization
requirements. The first bin is to provide flexibility regarding
corrosion control studies for systems that are reoptimizing existing
corrosion control treatment following a trigger level exceedance. In
the final rule, states are allowed to approve existing

corrosion control treatment modifications without a corrosion control
study for systems with lead levels between the trigger level and the
action level. To clarify the systems that are not eligible for this
flexibility, EPA added a definition of ``systems without corrosion
control treatment'' that includes 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. Another bin created in the
final rule identifies the subset of systems that must do a harvested
pipe loop study. This bin includes large and medium systems with LSLs
that exceed the lead action levels and any small system with LSLs that
selected corrosion control treatment option. For the systems in this
bin, Step 1 of the optimization or re-optimization process is the
construction and operation of the flow-through pipe loops after the
action level exceedance, which must be completed within one year of the
exceedance. EPA retained the requirement that coupon studies can only
be used as a screening tool for these systems. The final rule includes
requirements to allow coupon studies to be the basis for a treatment
recommendation tool for other systems that do not have a lead action
level exceedance and LSLs.
    In the final rule, EPA has also clarified that the orthophosphate
doses and benchmarks are orthophosphate measured as PO4. EPA
removed calcium carbonate stabilization as a corrosion control
treatment alternative in the final rule.

C. Lead Service Line Inventory

1. Proposed Revisions
    EPA proposed to improve the available information regarding LSL
numbers and locations by requiring an inventory of service line
materials to be prepared by CWSs and NTNCWSs. EPA proposed to require
these systems to submit an initial inventory within three years of
publication of the rule, and for the water systems to update the
inventory annually as they gather more information through the course
of their normal activities. EPA proposed requiring the inventory to
identify not only LSLs but also galvanized service lines that are or
were downstream of an LSL, service lines whose material composition is
unknown, and service lines known not to be LSLs. The proposed rule
required each LSL to be associated with a locational identifier. EPA
proposed that the inventory be made publicly available and proposed
that water systems serving greater than 100,000 people would be
required to make their inventory available electronically.
2. Public Comment and EPA's Response
    Several commenters supported requiring systems to make the LSL
inventory publicly accessible because transparency is a critical step
for building trust, informing and educating consumers about the sources
of lead in drinking water, and reducing risk. Some commenters did not
support a requirement to make the inventory publicly accessible,
raising concerns that it could infringe on customer privacy and add to
confusion, panic, and distrust of the water system, especially if the
inventory identifies a high number of LSLs or service lines where the
lead status is unknown. Commenters also raised concerns that the
requirement could result in unintended impacts to economic development
for a community and property values for individual locations with LSLs
or lead status unknown service lines. Some commenters raised concerns
with the requirement because there are alternatives to allowing open
access to the general public (e.g., the requirement for the PWS to
provide annual disclosure to customers with LSLs; a requirement to
release the information after account verification; or other non-
binding measures such as pre-purchase residential inspections).
    Many commenters supported the inclusion of specific street
addresses in the inventory, citing the increased transparency and the
potential to drive proactive LSLR. Some commenters noted that an
inventory without addresses would be of limited utility to consumers,
given that LSLs impact the individual locations where they are found.
Some commenters did not support a requirement to include addresses in
the inventory, citing local or state privacy laws that they claim would
prohibit the publication of address-level information in their
inventory.
    EPA agrees with commenters who support a requirement for water
systems to make the inventory publicly accessible. Informed customers
are better able to take actions to limit exposure to lead in drinking
water and make decisions regarding replacement of their portion of a
LSL, and to better understand the prevalence of lead sources in
drinking water. A Federal requirement for a publicly accessible
inventory that uses specific addresses is not necessary, and could
complicate implementation of the inventory requirements for those
systems that may have concerns about potential conflicts with state or
local privacy laws or constitutional protections; therefore, the final
rule only requires systems to provide a general location identifier in
the publicly accessible inventory. An address is not the only means by
which water systems can convey the location of LSLs, other location
identifiers could be used such as blocks, streets, landmarks, or other
geographic markers that are associated with an individual service line.
An inventory that is publicly available with location information
provides communities with updated information regarding the total
number of LSLs, galvanized requiring replacement lines, lead status
unknown lines, and non-LSLs, as well as the general areas where LSLs
and galvanized requiring replacement service lines are located. Making
this information publicly available also allows the community to track
LSLR and material composition verification progress over time. In
addition, prospective homebuyers could use the publicly accessible
inventory to determine whether and how to work with the homeowner, real
estate agent, or home inspector to identify a service line's material
composition. For publicly available inventories that do not include
addresses as location identifiers, consumers will be individually
notified of their service line material classification under 40 CFR
141.85(e), after the water system conducts its initial inventory and
annually thereafter. Finally, even though EPA has determined not to
establish a Federal requirement to provide specific addresses in the
inventory, this does not preclude water systems from doing so. Nor are
states precluded by the SDWA from requiring water systems to do so.
    EPA received a comment suggesting the final rule strengthen
inventory public accessibility requirements, making the inventory
available online and extending this requirement to systems serving less
than the proposed benchmark of 100,000 people. Requiring more
inventories to be available online, commenters said, would allow
consumers to more easily access the inventories. EPA agrees with these
commenters and is requiring online publishing in the final rule for
water systems serving over 50,000 persons, given that websites, social
media platforms, and cloud-based file sharing applications are widely
available and

can host information for free or low-cost.
    EPA received comments on other aspects of the inventory
requirements such as the feasibility of creating initial inventories
within three years after publication of the final rule. Some commenters
believed an inventory could be created within three years, while others
claimed that such an effort is not feasible. Some commenters noted the
absence of a deadline to verify all service line materials, as is
required in Michigan's LCR, and suggested that the final rule include a
deadline. Some commenters needed clarification regarding methods for
identifying LSLs.
    The Agency determined it is practicable and feasible for water
systems to prepare the initial inventory by the rule compliance date,
as the rule does not require a deadline to verify each service line's
composition, allowing unidentified materials to be classified as lead
status unknown. It is important that water systems complete the initial
LSL inventory within three years of publication of the final rule to
facilitate, for example, selection of tap sampling sites under new
tiering criteria and to inform consumers about the presence of a known
or potential LSL by the compliance date, which is based on Section
1412(b)(10) of the SDWA. The inventory is also critical to determining
the number of LSLs to be applied to the LSLR rate under a lead trigger
level exceedance and action level exceedance.
    EPA disagrees that an end date by which all LSLs and lead status
unknown service lines must be verified is warranted or appropriate. The
LCR is a national rule which applies to over 60,000 water systems with
very different circumstances, including but not limited to the number
of service connections, system size, the proportion of LSLs to total
service lines, the age of the system, and the accessibility or
existence of service line materials records. Water systems with limited
or nonexistent records will be more reliant on physical inspection of
service line materials, which will require more time and resources than
systems with robust records. Additionally, some service line material
investigations may require access to private property, but the customer
may deny access or not respond to water system outreach, which could
challenge a water system's ability to comply with a verification
deadline. Some records used for the initial inventory may be outdated
or inaccurate, requiring the inventory to be updated over time as new
information becomes available. For other systems (such as those with
very few lead status unknown service lines), a Federal deadline may
discourage or unnecessarily prolong the water system's inventorying
efforts. Therefore, EPA determined it is impractical to impose a single
deadline for completing an accurate inventory; it is more appropriately
treated as an ongoing effort that systems must engage in, while clearly
communicating to the public and the state the progress towards
completion. The final rule facilitates timely development and
verification of the inventory by requiring service line materials to be
tracked as they are encountered and through incentives to verify
unknowns. By requiring water systems to issue annual notification to
consumers served by unknowns, to include unknowns in the replacement
rate if the water system exceeds the lead trigger or action level, and
to implement risk mitigation measures after disturbance of an unknown,
EPA has created incentives for water systems to reduce the number of
unknown service lines in their inventory. EPA also requires that water
systems include in their LSLR plan a strategy for verifying the
material composition of lead status unknown service lines. An inventory
verification strategy can improve efficiency by allowing the water
system to integrate material composition investigations into its
existing standard operating procedures for other activities. For
example, if water system personnel are already deployed on a street for
a main replacement, they may visually inspect system-owned lead status
unknown service lines on that street or engage with affected customers
to determine the material composition of the service line entering the
home. Water systems may also create a strategy that involves proactive
investigation of service line material compositions which is
independent of other water system activities, such as the use of
predictive models to evaluate the probability a service line is lead
and other methods provided or required by the state. Such predictive
models could also inform water systems in how they can approach LSLR in
a more efficient manner. EPA encourages but does not require this
practice as it allows consumers with lead status unknown service lines
to be informed sooner about their service line material.
    EPA requested comment on the scope of the inventory, including
whether it should be required to include customer-owned service lines,
galvanized service lines, and lead status unknown service lines. Some
commenters believed that the water system should only be responsible
for inventorying the service lines under its control, which would
exclude all customer-owned service lines. Some commenters suggested
that lead status unknown service lines should not be included because
inventories with large numbers of unknowns could cause public alarm.
Other commenters did not object to inclusion of unknowns but sought for
water systems to have the ability to make a judgment about the
probability of an unknown being an LSL (for example, a new
classification such as ``Unknown but likely non-lead''). Some
commenters suggested lead connectors be inventoried.
    EPA disagrees with comments suggesting that the inventory
requirement in the rule should only apply to service lines if they are
owned by the system. Customer owned service lines are connected to
either a system-owned service line or main and therefore, they are
accessible to the system and historically, the LCR has not been limited
to system-owned portions of the distribution system. The LCR has
required systems to take actions with respect to portions of the
distribution system that are not owned by the water system, including
actions related to the materials evaluation and the determination of
the number of LSLs in the distribution system for calculating the
number of service lines required to be replaced. For example, the LCR
has required that ``[t]he system shall identify the initial number of
LSLs in its distribution system, including an identification of the
portion(s) owned by the system. . . .'' Similarly, the previous LCR has
provided that ``where the system does not own the entire LSL, the
system shall notify the owner of the line that the system will replace
the portion of the line that it owns and shall offer to replace the
owner's portion of the line.'' Moreover, where service line ownership
is divided between the system and the customer, water system actions
can release lead from customer-owned pipes and cause subsequent
customer lead exposure. For example, partial LSLR of the system-owned
portion can result in a lead spike on the customer-owned portion from
physical disturbance as well as lead release from galvanic corrosion.
Regarding inventory development, EPA notes that customer-owned service
lines are connected to either a system-owned service line or system-
owned water main and are therefore accessible to the system. Accounting
for locations of customer-owned LSLs will continue to be an integral
part of the rule; without it, water systems would not be able to

coordinate replacement of customer-owned LSLs simultaneously with
system-owned LSL, take required risk mitigation actions after
replacement of a partial LSLR, or provide notice to persons served by
LSLs.
    EPA disagrees that lead status unknown service lines should be
excluded from the inventory. As EPA explained in the proposal,
``[b]ecause water systems may not have complete records to enable them
to identify the material for every service line'' the proposed rule
would require water systems to identify those lines as unknown, and
then update the inventory on an annual basis to reflect more precise
information about those lines. (84 FR 61695). EPA determined that such
an approach strikes an appropriate balance between a voluntary and
mandatory requirement to conduct an accurate and complete inventory of
the service line materials in the distribution system. It provides
significant flexibility that would not be available if the rule
required an accurate and complete inventory by a fixed date; on the
other hand, by structuring the replacement requirements so as to
incentivize systems to verify the materials of unknown service lines,
completion of an accurate inventory is more than an aspirational goal.
Including unknown service lines in the inventory will demonstrate
transparency, build trust, and present an opportunity for customer
engagement, all of which should mitigate commenter concerns about
potential customer alarm about the presence of lead status unknown
service lines. Exclusion of lead status unknown service lines from the
inventory would likely cause significantly more confusion and alarm to
the consumers at locations that are excluded from the inventory
entirely. Some commenters asked that multiple classifications be
introduced for unknowns, for example ``unknown but likely non-lead'' or
``unknown--not lead,'' where records do not exist, but the water system
believes the service line is likely not an LSL. A requirement to
distinguish the categories of unknown service lines is not necessary
for the portions of the rule that use the inventory, and therefore, EPA
concluded it would not be appropriate to require in the final rule.
Water systems may elect to provide more information in the inventory
regarding their unknown lines as long as it clearly distinguishes
service lines classified as ``Lead status unknown'' from those whose
material has been verified through records or inspection. The
distinction between unknown and verified service lines is critical to
implementation of the LSLR requirements and will also help to avoid
confusion. EPA adjusted the terminology for unknowns from ``service
line of unknown material'' in the proposal to ``lead status unknown
service line'' in the final rule. This change clarifies that water
systems may classify a service line as ``non-lead'' rather than
``service line of unknown material'' where it knows that the service
line is not an LSL but does not know the precise material, such as
copper or plastic.
    EPA disagrees that the final rule should require lead connectors to
be included in the inventory. In many cases, records on lead connectors
are often extremely limited or may not exist at all. Unlike an
inventory of service lines, whose material can be visually inspected
often without excavation from inside the home or in the meter box, a
complete and accurate inventory of connectors would require excavation
that disturbs road pavement and repaving post-inspection--an
undertaking that EPA expects would not be feasible or practical for
most systems. Instead, EPA addresses the presence of lead connectors by
requiring that water systems replace system-owned lead connectors
whenever they are encountered during water system activities, such as
emergency repairs or planned infrastructure work, and to offer to
replace a customer-owned connector at no cost to the system. EPA
encourages water systems to voluntarily include information about lead
connectors in the inventory where such records exist.
    Commenters suggested that annual submission of the inventory to the
state would create burden for the water system to submit its inventory
and for the state to review it. EPA agrees that for some water systems,
annual inventory updates may not be necessary. For example, water
systems below the lead trigger level are not required to execute a
system-wide LSLR program, meaning they will have fewer inventory
changes to report. EPA agrees that linking inventory update frequency
with the tap sampling monitoring period would be efficient for water
systems and states because tap sampling must be conducted at LSL sites.
Changes in the inventory and any resulting changes to the tap sampling
plan made to ensure samples are collected at LSL sites can be reviewed
by states concurrently. EPA also agrees that for water systems on 6-
month monitoring, annual inventory updates are more appropriate given
that LSLR rates apply annually.
3. Final Rule Requirements
    The final rule requires all water systems to create a publicly
accessible LSL inventory. The initial inventory must be available
within three years and updated over time to reflect changes, such as
verification of lead status unknown service line material compositions
or LSLs that have been replaced. All water systems must create an
inventory, regardless of size or other water system characteristics,
and the inventory must include all service lines in the distribution
system, without exclusions. Water systems with only non-LSLs are
required to conduct an initial inventory, but they are not required to
provide inventory updates to the state or the public and they may
fulfill the requirement to make the inventory publicly accessible with
a statement that there are no LSLs, along with a general description of
the methods used to make that determination. For example, water systems
where the entire distribution system (including customer-owned portions
of the service line) was constructed after a state or Federal lead ban
may designate applicable service lines as ``Non-lead.'' There is no
deadline to investigate the material composition of all lead status
unknown service lines. Water systems must create a strategy in their
LSLR plan for investigating lead status unknown service lines in their
inventory. This strategy, coupled with the incentive to investigate
unknowns to ease future LSLR burden, will encourage water systems to
verify all unknown service line materials in a timely manner. Other
rule provisions ensure that customers served by lead status unknown
service lines receive protections while inventory development is in
progress, such as the requirement to receive targeted information that
their service line material is unknown but may be an LSL.
    While EPA retained the proposed inventory classifications, the
final rule modifies some terminology. To avoid potential customer
confusion, galvanized service lines that are or were downstream of an
LSL are no longer required to be classified as an LSL. Instead, they
must be labeled ``Galvanized requiring replacement'' which allows their
correct material composition to be listed while maintaining they are
not to be classified as ``Non-lead'' because they must be replaced as
part of the system's LSLR program. As previously described, the
proposed ``Service lines of unknown material'' are referred to as
``Lead status unknown service lines'' in the final rule.

The classification of ``non-lead'' means that, as in the proposed rule,
the water system does not need to identify the exact material of a
service line, such as plastic or copper, if it is not an LSL or
galvanized requiring replacement service line.
    The final rule does not include a requirement to investigate or
inventory lead connectors for the reasons discussed above. EPA
recommends reviewing records on connector material composition during
the records search for the initial inventory. EPA also recommends but
is not requiring that water systems inventory connector materials where
records exist to provide additional information to consumers about
additional lead sources that could contribute to lead in drinking water
serving the residence.
    The final rule incorporates commenter suggestions to link the
inventory update submission frequency with the system's compliance
monitoring period or annually, whichever is greater. Because tap
sampling must be conducted at LSL sites, changes in the inventory and
any resulting changes to the tap sampling plan, to ensure samples are
collected at LSL sites, can be reviewed by states concurrently. Water
systems on triennial monitoring will be required to provide LSL
inventory updates every three years. Water systems that exceed the lead
trigger level must conduct tap sampling annually, and therefore, these
systems must provide LSL inventory updates annually. Water systems that
exceed the lead action level will conduct tap sampling every six
months; however, they are required to update the inventory annually.
    The final rule requires the LSL inventory to be publicly
accessible. The threshold required for water systems to publish their
inventory online was reduced to 50,000 persons from the threshold of
100,000 as proposed. Internet platforms, such as websites, cloud-based
file sharing applications, and social media, are widely available and
can host information for free or low-cost.
    These provisions will strengthen the public accessibility to
information in the inventory. EPA also added a requirement for the
Consumer Confidence Report to include a statement that a service line
inventory has been prepared and is available for review either online
or at the water system offices.
    The final rule requires the publicly accessible inventory to
provide a location identifier for lead service lines. The location
identifier could be a general location such as a street, block,
intersection, or landmark, or other geographic marker associated with
the service line. An inventory created and maintained internally by
water systems to track service line materials may use the specific
address of each service line in order for the water system to provide
the required notification under Sec.  141.85(e), but the final rule
does not require that the system make the exact street addresses
publicly available. Instead, the final rule gives the water system
flexibility to determine which location identifier best meets the needs
of its own community.

D. Lead Service Line Replacement

1. Proposed Revisions
    EPA proposed to accelerate lead service line replacement (LSLR) by
proposing LSLR requirements target systems with higher lead levels and
that address weaknesses in the current rule to achieve full LSLR in the
communities where they are needed most. EPA proposed to require all
water systems to replace the system-owned portion of an LSL after they
were notified of a customer-initiated replacement of their portion. EPA
proposed that water systems above the lead trigger level but at or
below the lead action level would be required to implement a ``goal-
based'' LSLR program at a rate approved by the state primacy agency.
Water systems that exceeded the lead action level would be required to
conduct mandatory, full LSLR at a minimum rate of three percent
annually. While the proposal did not include a prohibition on partial
replacements, it did not incentivize them and included required