[Federal Register Volume 80, Number 238 (Friday, December 11, 2015)]
[Proposed Rules]
[Pages 76897-76923]
[FR Doc No: 2015-30824]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 141

[EPA-HQ-OW-2015-0218; FRL-9935-74-OW]
RIN 2040-AF10

Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4)
for Public Water Systems and Announcement of a Public Meeting

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule and notice of public meeting.

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SUMMARY: The U.S. Environmental Protection Agency (EPA) is proposing a
Safe Drinking Water Act (SDWA) rule that requires public water systems
to collect occurrence data for contaminants that may be present in tap
water but are not yet subject to EPA's drinking water standards set
under SDWA. This rule, revised every five years as required by SDWA,
benefits public health by providing EPA and other interested parties
with scientifically valid data on the national occurrence of selected
contaminants in drinking water, such as cyanotoxins associated with
harmful algal blooms. This data set is one of the primary sources of
information on occurrence, levels of exposure and population exposure
the Agency uses to develop regulatory decisions for emerging
contaminants in the public drinking water supply. This proposal
identifies eleven analytical methods to support water system monitoring
for a total of 30 chemical contaminants/groups, consisting of ten
cyanotoxins/groups; two metals; eight pesticides plus one pesticide
manufacturing byproduct (hereinafter collectively referred to as
``pesticides''); three brominated haloacetic acid groups of
disinfection byproducts; three alcohols; and three semivolatile organic
chemicals. EPA is also announcing a public webinar to discuss this
proposal of the fourth Unregulated Contaminant Monitoring Rule.

DATES: Comments must be received on or before February 9, 2016. Under
the Paperwork Reduction Act (PRA), comments on the information
collection provisions are best assured of consideration if the Office
of Management and Budget (OMB) receives a copy of your comments on or
before January 11, 2016. The public webinar will be held on January 13,
2016, from 1:00 p.m.. to 4:30 p.m., eastern time. Persons wishing to
participate in the webinar must register

by January 10, 2016, as described in section II.M.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-HQ-OW-
2015-0218, at http://www.regulations.gov. Follow the online
instructions for submitting comments. Once submitted, comments cannot
be edited or removed from Regulations.gov. The EPA may publish any
comment received to its public docket. Do not submit electronically any
information you consider to be Confidential Business Information (CBI)
or other information whose disclosure is restricted by statute.
Multimedia submissions (audio, video, etc.) must be accompanied by a
written comment. The written comment is considered the official comment
and should include discussion of all points you wish to make. The EPA
will generally not consider comments or comment contents located
outside of the primary submission (i.e. on the web, cloud, or other
file sharing system). For additional submission methods, the full EPA
public comment policy, information about CBI or multimedia submissions,
and general guidance on making effective comments, please visit http://www2.epa.gov/dockets/commenting-epa-dockets.

FOR FURTHER INFORMATION CONTACT: Brenda D. Parris, Standards and Risk
Management Division (SRMD), Office of Ground Water and Drinking Water
(OGWDW) (MS 140), Environmental Protection Agency, 26 West Martin
Luther King Drive, Cincinnati, OH 45268; telephone number: (513) 569-
7961; or email address<EMAIL_ADDRESS>or Melissa Simic, SRMD,
OGWDW (MS 140), Environmental Protection Agency, 26 West Martin Luther
King Drive, Cincinnati, Ohio 45268; telephone number:<PHONE_NUMBER>;
or email address<EMAIL_ADDRESS>For general information,
contact the Safe Drinking Water Hotline. Callers within the United
States can reach the Hotline at<PHONE_NUMBER>. The Hotline is open
Monday through Friday, excluding federal holidays, from 10 a.m. to 4
p.m., eastern time. The Safe Drinking Water Hotline can also be found
on the Internet at: http://water.epa.gov/drink/hotline/.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. General Information
    A. Does this action apply to me?
    B. What action is the Agency taking and why?
    C. What is the Agency's authority for taking this action?
    D. What is the estimated cost of this proposed action?
II. Background
    A. How has EPA implemented the Unregulated Contaminant
Monitoring Program?
    B. How are the Contaminant Candidate List (CCL), the UCMR
program, the Regulatory Determination process and the NCOD
interrelated?
    C. What notable changes are being proposed for UCMR 4?
    D. How did EPA prioritize candidate contaminants and what
contaminants are proposed for UCMR 4?
    E. What is the proposed applicability date?
    F. What are the proposed UCMR 4 sampling design and timeline of
activities?
    1. Sampling Frequency, Timing
    2. Sampling Locations
    3. Phased Sample Analysis for Microcystins
    4. Representative Sampling
    5. Summary
    G. What are reporting requirements for UCMR 4?
    1. Data Elements
    2. Duplicate Samples
    H. What are Minimum Reporting Levels (MRLs) and how were they
determined?
    I. How do laboratories become approved to conduct UCMR 4
analyses?
    1. Request to Participate
    2. Registration
    3. Application Package
    4. EPA's Review of Application Package
    5. Proficiency Testing
    6. Written EPA Approval
    J. What documents are being incorporated by reference?
    1. Methods From the U.S. Environmental Protection Agency
    2. Methods From ``ASTM International''
    3. Methods From ``Standard Methods for the Examination of Water
& Wastewater''
    4. Methods From ``Standard Methods Online''
    5. Method From ``Ohio EPA''
    K. What is the states' role in the UCMR program?
    L. What stakeholder meetings have been held in preparation for
UCMR 4?
    M. How do I participate in the upcoming stakeholder meeting?
    1. Webinar Participation
    2. Webinar Materials
    N. How did EPA consider Children's Environmental Health?
    O. How did EPA address Environmental Justice?
III. Statutory and Executive Order Reviews
    A. Executive Order 12866: Regulatory Planning and Review and
Executive Order 13563: Improving Regulation and Regulatory Review
    B. Paperwork Reduction Act (PRA)
    C. Regulatory Flexibility Act (RFA)
    D. Unfunded Mandates Reform Act (UMRA)
    E. Executive Order 13132: Federalism
    F. Executive Order 13175: Consultation and Coordination With
Indian Tribal Governments
    G. Executive Order 13045: Protection of Children From
Environmental Health Risks and Safety Risks
    H. Executive Order 13211: Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution or Use
    I. National Technology Transfer and Advancement Act and 1 CFR
Part 51
    J. Executive Order 12898: Federal Actions To Address
Environmental Justice in Minority Populations and Low-Income
Populations
IV. References

Abbreviations and Acronyms

[mu]g/L Microgram per liter
ADDA (2S, 3S, 8S, 9S, 4E, 6E)-3-amino-9-methoxy-2,6,8-trimethyl-10-
phenyl-4, 6-decadienoic acid
ASDWA Association of State Drinking Water Administrators
ASTM ASTM International
CAS Chemical Abstract Service
CBI Confidential Business Information
CCC Continuing Calibration Check
CCL Contaminant Candidate List
CFR Code of Federal Regulations
CLDA Chlorine Dioxide Applied After SR Sample Location
CLDB Chlorine Dioxide Applied Before SR Sample Location
CWS Community Water System
DBPR Disinfectants and Disinfection Byproducts Rule
DSMRT Distribution System Maximum Residence Time
ELISA Enzyme-linked Immunosorbent Assay
EPA United States Environmental Protection Agency
EPTDS Entry Point to the Distribution System
FR Federal Register
GC Gas Chromatography
GC/ECD Gas Chromatography/Electron Capture Detection
GC/MS Gas Chromatography/Mass Spectrometry
GW Ground Water
GWUDI Ground Water Under the Direct Influence of Surface Water
HAAs Haloacetic Acids
HAA5 Dibromoacetic Acid, Dichloroacetic Acid, Monobromoacetic Acid,
Monochloroacetic Acid, Trichloroacetic Acid
HAA6Br Bromochloroacetic Acid, Bromodichloroacetic Acid,
Dibromoacetic Acid, Dibromochloroacetic Acid, Monobromoacetic Acid,
Tribromoacetic Acid
HAA9 Bromochloroacetic Acid, Bromodichloroacetic Acid,
Chlorodibromoacetic Acid, Dibromoacetic Acid, Dichloroacetic Acid,
Monobromoacetic Acid, Monochloroacetic Acid, Tribromoacetic Acid,
Trichloroacetic Acid
HPXA Hydrogen Peroxide Applied After Source Water Sample Location
HPXB Hydrogen Peroxide Applied Before Source Water Sample Location
IC-MS/MS Ion Chromatography/Tandem Mass Spectrometry
ICP-MS Inductively Coupled Plasma Mass Spectrometry
ICR Information Collection Request
IDC Initial Demonstration of Capability
IS Internal Standard
LFB Laboratory Fortified Blank

LRB Laboratory Reagent Blank
LCMRL Lowest Concentration Minimum Reporting Level
LC/ECI-MS/MS Liquid Chromatography/Electrospray Ionization/Tandem
Mass Spectrometry
LC/MS/MS Liquid Chromatography/Tandem Mass Spectrometry
LT2 Long Term 2 Enhanced Surface Water Treatment Rule
M Million
MRL Minimum Reporting Level
NAICS North American Industry Classification System
NCOD National Drinking Water Contaminant Occurrence Database
NPDWRs National Primary Drinking Water Regulations
NTNCWS Non-transient Non-community Water System
OGWDW Office of Ground Water and Drinking Water
OMB Office of Management and Budget
PA Partnership Agreement
PEMA Permanganate Applied After Source Water Sample Location
PEMB Permanganate Applied Before Source Water Sample Location
PRA Paperwork Reduction Act
PT Proficiency Testing
PWS Public Water System
QCS Quality Control Sample
QH Quality HAA Sample
RFA Regulatory Flexibility Act
SDWA Safe Drinking Water Act
SDWARS Safe Drinking Water Accession and Review System
SDWIS/Fed Federal Safe Drinking Water Information System
SM Standard Methods
SMP State Monitoring Plan
SOP Standard Operating Procedure
SPE Solid Phase Extraction
SR Source Water
SRF Drinking Water State Revolving Fund
SRMD Standards and Risk Management Division
SUR Surrogate Standard
SVOCs Semivolatile Organic Chemicals
SW Surface Water
TNCWS Transient Non-Community Water System
TOC Total Organic Carbon
UCMR Unregulated Contaminant Monitoring Rule
UMRA Unfunded Mandates Reform Act of 1995
USEPA United States Environmental Protection Agency

I. General Information

A. Does this action apply to me?

    Public water systems (PWSs) would be regulated by this proposed,
fourth Unregulated Contaminant Monitoring Rule (UCMR 4). PWSs are
systems that provide water for human consumption through pipes, or
other constructed conveyances, to at least 15 service connections or
that regularly serve an average of at least 25 individuals daily at
least 60 days out of the year. Under this proposal, all large community
and non-transient non-community water systems (NTNCWSs) serving more
than 10,000 people would be required to monitor. A community water
system (CWS) means a PWS that has at least 15 service connections used
by year-round residents or regularly serves at least 25 year-round
residents. A NTNCWS means a PWS that is not a CWS and that regularly
serves at least 25 of the same people over six months per year. A
nationally representative sample of CWSs and NTNCWSs serving 10,000 or
fewer people would also be required to monitor (see ``Statistical
Design and Sample Selection for the Unregulated Contaminant Monitoring
Regulation'' (USEPA, 2001b) for a description of the statistical
approach for the nationally representative sample). As is generally the
case for UCMR monitoring, transient non-community water systems
(TNCWSs) (i.e., non-community water systems that do not regularly serve
at least 25 of the same people over six months per year) would not be
required to monitor under UCMR 4. States, territories and tribes, with
primary enforcement responsibility (primacy) to administer the
regulatory program for PWSs under SDWA, can participate in the
implementation of UCMR 4 through Partnership Agreements (PAs) (see
discussion of PAs in section II.K). Primacy agencies with PAs can
choose to be involved in various aspects of the UCMR 4 monitoring for
PWSs they oversee; however, the PWS remains responsible for compliance.
Potentially regulated categories and entities are identified in the
following table.

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                                     Examples of
           Category             potentially regulated      NAICS \a\
                                       entities
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State, local, & tribal          States, local and                 924110
 governments.                    tribal governments
                                 that analyze water
                                 samples on behalf of
                                 PWSs required to
                                 conduct such
                                 analysis; states,
                                 local and tribal
                                 governments that
                                 directly operate
                                 CWSs and NTNCWSs
                                 required to monitor.
Industry......................  Private operators of              221310
                                 CWSs and NTNCWSs
                                 required to monitor.
Municipalities................  Municipal operators               924110
                                 of CWSs and NTNCWSs
                                 required to monitor.
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\a\ NAICS = North American Industry Classification System.

    This table is not intended to be exhaustive, but rather provides a
guide for readers regarding entities likely to be regulated by this
action. This table summarizes the types of entities that EPA is aware
could potentially be regulated by this action. If you are uncertain
whether your entity is regulated by this action after carefully
examining the definition of PWS found in Sec. Sec.  141.2 and 141.3,
and the applicability criteria found in Sec.  141.40(a)(1) and (2) of
Title 40 in the Code of Federal Regulations (CFR), please consult the
contacts listed in the preceding FOR FURTHER INFORMATION CONTACT
section.

B. What action is the Agency taking and why?

    EPA is proposing a rule to require PWSs to analyze drinking water
samples for unregulated contaminants that do not have health based
standards set under SDWA and to report their results to EPA. This will
be the fourth national monitoring effort under the UCMR program (see
section II.D). The monitoring provides data to inform future regulatory
actions to protect public health.
    The public will benefit from information about whether or not
unregulated contaminants are present in their drinking water. If
contaminants are not found, consumer confidence in their drinking water
will improve. If contaminants are found, illnesses may be avoided when
subsequent actions, such as regulations, reduce or eliminate those
contaminants.

C. What is the Agency's authority for taking this action?

    As part of its responsibilities under SDWA, EPA implements section
1445(a)(2), Monitoring Program for Unregulated Contaminants. This
section, as amended in 1996, requires that once every five years,
beginning in August 1999, EPA issue a list of no more than 30
unregulated contaminants to be monitored by PWSs. SDWA requires that
EPA enter the monitoring data into the Agency's publically available
National Contaminant Occurrence Database (NCOD). EPA's UCMR program
must ensure that systems serving a population larger than 10,000
people, as well as a nationally representative

sample of PWSs serving 10,000 or fewer people, are required to monitor.
EPA must vary the frequency and schedule for monitoring based on the
number of persons served, the source of supply and the contaminants
likely to be found. EPA is using this authority as the basis for
monitoring 29 of the 30 contaminants/groups proposed under this rule.
    Section 1445(a)(1)(A) of SDWA, as amended in 1996, requires that
every person who is subject to any SDWA requirement establish and
maintain such records, make such reports, conduct such monitoring and
provide such information as the Administrator may reasonably require by
regulation to assist the Administrator in establishing SDWA
regulations. Pursuant to this provision, EPA can also require the
monitoring of contaminants already subject to EPA's drinking water
standards. EPA is using this authority as the basis for monitoring one
of the chemical groups (Haloacetic Acids 5 (HAA5)) proposed under this
rule. Sample collection and analysis for HAA5 can be done concurrent
with the unregulated HAA monitoring described in section II.F
(resulting in no substantive additional burden) and would allow EPA to
better understand co-occurrence between regulated and unregulated
disinfection byproducts.
    Hereinafter, all 30 proposed contaminants/groups are collectively
referred to as ``contaminants.''

D. What is the estimated cost of this proposed action?

    EPA estimates the total average national cost of this proposed
action will be $25.3 million per year from 2017-2021. EPA has
documented the assumptions and data sources used in the preparation of
this estimate in the Information Collection Request (ICR) (USEPA,
2015a). EPA proposes using eleven analytical methods (eight EPA-
developed analytical methods, one state-developed methodology and two
alternate equivalent consensus organization-developed methods) to
analyze samples for 30 UCMR 4 chemical contaminants. EPA's estimate of
the analytical cost for the UCMR 4 contaminants and related indicators
is $2,562 per sample set. EPA calculated these costs by summing the
laboratory unit cost of each method. Exhibit 1 presents a breakdown of
EPA estimated annual average national costs. Estimated PWS (i.e., large
and very large) and EPA costs reflect the analytical cost (i.e., non-
labor) for all UCMR 4 methods. EPA pays for the analytical costs for
all systems serving a population of 10,000 or fewer people. Laboratory
analysis and sample shipping account for approximately 80% of the total
national cost for UCMR 4 implementation. EPA estimated laboratory unit
costs based on consultations with multiple commercial drinking water
laboratories and, in the case of new methods, a review of the costs of
analytical methods similar to those proposed in this action. The cost
of the laboratory methods includes shipping as part of the cost for the
analysis.
    EPA expects that states would incur labor costs associated with
voluntary assistance with UCMR 4 implementation. EPA estimated state
costs using the relevant assumptions from the State Resource Model that
was developed by the Association of State Drinking Water Administrators
(ASDWA) (ASDWA, 2013) to help states forecast resource needs. Model
estimates were adjusted to account for actual levels of state
participation under UCMR 3. State participation is voluntary; thus, the
level of effort is expected to vary among states and would depend on
their individual agreements with EPA.
    EPA assumes that one-third of the systems would monitor during each
of the three monitoring years from January 2018 through December 2020.
The total estimated annual costs (labor and non-labor) would be
incurred as follows:

           Exhibit 1--Estimated Average Annual Costs of UCMR 4
------------------------------------------------------------------------
                                                        Avg. annual cost
                      Respondent                        all respondents
                                                        (2017-2021) \ 1\
------------------------------------------------------------------------
Small Systems (25-10,000), including labor \2\ only              $0.16 m
 (non-labor costs \3\ paid for by EPA)...............
Large Systems (10,001-100,000), including labor and              $15.7 m
 non-labor costs.....................................
Very Large Systems (100,001 and greater), including               $4.3 m
 labor and non-labor costs...........................
States, including labor costs related to                         $0.50 m
 implementation coordination.........................
EPA, including labor for implementation, non-labor                $4.7 m
 for small system testing............................
------------------------------------------------------------------------
    AVERAGE ANNUAL NATIONAL TOTAL....................            $25.3 m
------------------------------------------------------------------------
\1\ Totals may not equal the sum of components due to rounding.
\2\ Labor costs pertain to systems, states and EPA. Costs include
  activities such as reading the rule, notifying systems selected to
  participate, sample collection, data review, reporting and record
  keeping.
\3\ Non-labor costs would be incurred primarily by EPA and by very large
  and large PWSs. They include the cost of shipping samples to
  laboratories for testing and the cost of the laboratory analyses.

    Additional details regarding EPA's cost assumptions and estimates
can be found in the ``DRAFT Information Collection Request for the
Unregulated Contaminant Monitoring Rule (UCMR 4)'' (USEPA, 2015a) ICR
Number 2192.07, which presents estimated cost and burden for the 2017-
2019 period, consistent with the 3-year time frame for ICRs. Estimates
of costs over the entire 5-year UCMR 4 sequence of 2017-2021 are
attached as an appendix to the ICR. Copies of the ICR and its appendix
may be obtained from the EPA public docket for this proposed rule,
under Docket ID No. EPA-HQ-OW-2015-0218.

II. Background

A. How has EPA implemented the unregulated contaminant monitoring
program?

    EPA published the list of contaminants for the first UCMR (UCMR 1)
in the Federal Register (FR) on September 17, 1999 (64 FR 50556,
(USEPA, 1999)), the second UCMR (UCMR 2) on January 4, 2007 (72 FR 368,
(USEPA, 2007)) and the third UCMR (UCMR 3) on May 2, 2012 (77 FR 26072,
(USEPA, 2012c)). EPA established a three-tiered approach for monitoring
contaminants under the UCMR program that takes into account the
availability of analytical methods, the source of water supply and the
contaminants likely to be found. Assessment Monitoring for ``List 1''
contaminants typically relies on analytical methods, techniques or
technologies that are in common use by drinking water laboratories.
Screening Survey monitoring for ``List 2''

contaminants typically relies on newer analytical methods that are not
as commonly used, such that laboratory capacity to perform List 2
analyses may be limited. Finally, Pre-Screen Testing for ``List 3''
contaminants is often associated with analytical methods that are very
recently developed and/or are particularly complex. In addition to
method complexity and laboratory capacity, EPA considers sampling
frequency and/or the relevant universe of PWSs when deciding which of
the three tiers is appropriate for a contaminant.
    EPA designed the Assessment Monitoring sampling approach (USEPA,
2001b) to ensure that sample results would yield a high level of
confidence and a low margin of error. The design for a nationally
representative sample of small systems called for the sample to be
stratified by water source type (ground water (GW) or surface water
(SW)), service size category and state (where each state is allocated a
minimum of two systems in its state monitoring plan (SMP)).
    This action proposes 30 contaminants for List 1, Assessment
Monitoring from 2018-2020, with pre-monitoring activity in 2017 and
post-monitoring activity in 2021. EPA developed this proposal after
considering input from an EPA-state workgroup as well as other
stakeholders.

B. How are the Contaminant Candidate List (CCL), the UCMR program, the
Regulatory Determination process and the NCOD interrelated?

    Under the 1996 amendments to SDWA, Congress established a stepwise,
risk-based approach for determining which contaminants would become
subject to drinking water standards. Under the first step, EPA is
required to publish, every five years, a list of contaminants that are
not yet regulated but which are known or anticipated to occur in PWSs;
this is the Contaminant Candidate List (CCL). Under the second step,
EPA must require, every five years, monitoring of up to 30 unregulated
contaminants to determine their occurrence in drinking water systems;
this is the UCMR program. Under the third step, EPA is required to
determine, every five years, whether or not at least five contaminants
from the CCL warrant regulation, based in part on the UCMR occurrence
information; this is known as a Regulatory Determination where the
following questions are evaluated:
    (1) Which contaminants may have an adverse effect on human health?
    (2) Which contaminants are known to occur or are likely to occur in
drinking water with a frequency and at levels of public health concern?
    (3) Does regulation of such contaminants present a meaningful
opportunity for risk reduction? Finally, SDWA requires EPA to issue
national primary drinking water regulations (NPDWRs) for contaminants
the Agency determines should be regulated.
    The CCL process identifies contaminants that may require
regulation, while the UCMR program helps provide the data necessary for
the Regulatory Determination process outlined above. The data collected
through the UCMR program are stored in the NCOD to facilitate analysis
and review of contaminant occurrence, and support the Administrator's
determination on whether regulation of a contaminant is in the public
health interest, as required under SDWA section 1412(b)(1). UCMR
results can be viewed by the public at: http://www2.epa.gov/dwucmr.

C. What notable changes are being proposed for UCMR 4?

    This proposed action refines the existing UCMR, as reflected in the
Code of Federal Regulations, to address the contaminants proposed for
UCMR 4 monitoring and to reflect lessons learned through prior
experience implementing UCMRs. EPA's proposed approach and rationale
for changes are described in the following sections. Key aspects of the
UCMR program that would remain the same, and are outside the scope of
today's proposal, include direct implementation of the rule by EPA; the
number and types of systems included in Assessment Monitoring for the
majority of the proposed contaminants; and EPA funding for the small
system testing. Proposed changes include the list of UCMR 4
contaminants, the analytical methods, monitoring time frame, sampling
locations, the revised data elements outlined in Exhibit 2 and
conforming and editorial changes, such as those necessary to remove
requirements solely related to UCMR 3. A track-changes version of the
rule language comparing UCMR 3 to the proposed changes for UCMR 4 is
included in the public docket (Docket ID No. EPA-HQ-OW 2015-0218) for
this proposed rule (USEPA, 2015h).

                                 Exhibit 2--Notable Changes Proposed for UCMR 4
----------------------------------------------------------------------------------------------------------------
                        CFR Rule section
----------------------------------------------------------------  Description of rule change     Corresponding
                Number                     Title/Description                                    preamble section
----------------------------------------------------------------------------------------------------------------
Sec.   141.40(a)(3)..................  Analytes to be monitored  Revises Table 1 to include a               II.D
                                        and related               new list of contaminants
                                        specifications.           and associated analytical
                                                                  methods.
Sec.  Sec.   141.35(a) and 141.40(a).  Applicability...........  Revises the Federal Safe                   II.E
                                                                  Drinking Water Information                II.F
                                                                  System (SDWIS/Fed)
                                                                  applicability date (i.e.,
                                                                  the date used to determine
                                                                  which systems are subject
                                                                  to monitoring) to December
                                                                  31, 2015.
                                                                 Revises the monitoring dates
                                                                  to January 2018 through
                                                                  December 2020.

Sec.   141.40(a)(4)..................  Sampling design           Updates Table 2 to change                  II.F
                                        requirements--Frequency.  the sample collection time
                                                                  frame to March--November,
                                                                  and excludes December--
                                                                  February. Additionally,
                                                                  updates the frequency such
                                                                  that, with the exception of
                                                                  cyanotoxins, monitoring
                                                                  would occur every two
                                                                  months (bi-monthly) for SW
                                                                  or ground water under the
                                                                  direct influence of surface
                                                                  water (GWUDI) systems and
                                                                  every six months for GW
                                                                  systems.
                                                                 Updates Table 2 to include
                                                                  monitoring requirements for
                                                                  cyanotoxins for PWSs with
                                                                  SW and GWUDI sources at a
                                                                  frequency of twice a month
                                                                  for four consecutive months
                                                                  (for a total of eight
                                                                  cyanotoxin sampling events).
Sec.   141.40(a)(4)..................  Sampling design           Specifies revised sampling                 II.F
                                        requirements--Location.   locations for Assessment
                                                                  Monitoring, including HAA5
                                                                  Stage 2 compliance and/or
                                                                  distribution system maximum
                                                                  residence time (DSMRT)
                                                                  locations for the
                                                                  brominated haloacetic acids
                                                                  (HAAs), and source water
                                                                  intake locations for total
                                                                  organic carbon (TOC), total
                                                                  microcystins (i.e. the sum
                                                                  of congeners as measured by
                                                                  ADDA-ELISA), pH and
                                                                  temperature.
Sec.   141.35(e).....................  Reporting requirements--  Updates, revises, adds and               II.G.1
                                        Data elements.            removes data elements to
                                                                  account for the
                                                                  contaminants being
                                                                  proposed, and requires the
                                                                  reporting of quality
                                                                  control data by all
                                                                  laboratories.
Sec.   141.40(a)(4)(ii)(F)...........  Small systems sampling    Removes the requirement for              II.G.2
                                        requirements--Duplicate   small system duplicate
                                        samples.                  quality control samples,
                                                                  although EPA may in the
                                                                  future select a subset of
                                                                  systems to collect
                                                                  duplicate samples if the
                                                                  Agency becomes aware of a
                                                                  need to include this type
                                                                  of quality control.
----------------------------------------------------------------------------------------------------------------

D. How did EPA prioritize candidate contaminants and what contaminants
are proposed for UCMR 4?

    In establishing the proposed list of contaminants for UCMR 4, EPA
started with a priority set of contaminants from the draft fourth
Contaminant Candidate List (CCL 4), which includes 100 chemicals or
chemical groups and 12 microbes (80 FR 6076, February 4, 2015 (USEPA,
2015b)). The evaluation and selection process that led to the draft CCL
4 carried forward the final list of CCL 3 contaminants (except for
those with regulatory determinations), requested and evaluated
contaminant nominations from the public and evaluated any new data from
previous negative regulatory determinations for potential inclusion on
CCL 4 (77 FR 27057, May 8, 2012 (USEPA, 2012b)).
    EPA selected the proposed UCMR 4 contaminants using a stepwise
prioritization process. The first step included identifying
contaminants that: (1) Were not monitored under UCMR 2 or UCMR 3; (2)
are anticipated to have significant occurrence nationally; and (3) are
expected to have a completed, validated drinking water method in time
for rule proposal. This resulted in a set of 45 draft CCL 4
contaminants and another set of related non-CCL analytes with potential
health effects of concern that can be measured concurrently using the
analytical methods for the CCL contaminants. Including related non-CCL
analytes creates a more cost-effective design and reduces the
likelihood of needing to include them in a subsequent UCMR.
    The next step was to select contaminants associated with one or
more of the following considerations: an available health assessment to
facilitate regulatory determinations; high public concern; critical
health endpoints (e.g., likely or suggestive carcinogen); active use
(e.g., pesticides); and an occurrence data gap. This step identified 31
CCL contaminants, and 18 related non-CCL analytes that can be measured
using the analytical methods for the CCL contaminants.
    During the final step, EPA considered workgroup and stakeholder
input; looked at cost-effectiveness of the method/contaminant groups;
considered implementation factors (e.g., laboratory capacity); and
further evaluated health, occurrence, and persistence/mobility data to
identify a proposed list of 30 UCMR 4 contaminants.
    Further information on this prioritization process, as well as
contaminant-specific information (source, use, production, release,
persistence, mobility, health effects and occurrence), that EPA used to
select the proposed analyte list, is contained in ``UCMR 4 Candidate
Contaminants--Information Compendium'' (USEPA, 2015i). Copies of the
Compendium may be obtained from the EPA public docket for this proposed
rule, under Docket ID No. EPA-HQ-OW-2015-0218.
    EPA invites comment on the proposed UCMR 4 contaminants and their
associated analytical methods identified in Exhibit 3, as well as any
other priority contaminants commenters wish to recommend. In
particular, the Agency welcomes comments on the following contaminants
that were considered by the workgroup, but not included in the proposed
list because they were deemed a lower UCMR 4 priority than the
contaminants identified in Exhibit 3: Legionella pneumophila and
Mycobacterium avium (both are part of the draft CCL 4); ammonia
(considered as an indicator of distribution system nitrification
potential); and the pesticides vinclozolin, hexazinone and disulfoton
(additional analytes in EPA Method 525.3). More specific information on
why these contaminants were not included on the proposed list can be
found in the Information Compendium (USEPA, 2015i) cited

above. In your comments, please identify the following: Any new
contaminant(s) that you think the Agency should include in UCMR 4
monitoring; any contaminant(s) in Exhibit 3 that you think represent a
lower priority than your new recommendation(s) or that should otherwise
be removed from the list; the recommended analytical method(s) for any
new contaminant(s) that you propose; and other relevant details (e.g.,
reporting level, sampling location and sampling frequency). Comments
that provide supporting data or rationale are especially helpful to the
Agency.

                 Exhibit 3--30 Proposed UCMR 4 Analytes
------------------------------------------------------------------------

------------------------------------------------------------------------
                             List 1 Analytes
------------------------------------------------------------------------
                  One Cyanotoxin Group Using ELISA \1\
------------------------------------------------------------------------
total microcystins
------------------------------------------------------------------------
        Seven Cyanotoxins Using EPA Method 544 (SPE LC/MS/MS) \2\
------------------------------------------------------------------------
microcystin-LA                              microcystin-RR
microcystin-LF                              microcystin-YR
microcystin-LR                              Nodularin
microcystin-LY
------------------------------------------------------------------------
         Two Cyanotoxins Using EPA Method 545 (LC/ECI-MS/MS) \3\
------------------------------------------------------------------------
anatoxin-a                                  Cylindrospermopsin
------------------------------------------------------------------------
  Two Metals Using EPA Method 200.8 (ICP-MS) \4\ or Alternate SM \5\ or
                                ASTM \6\
------------------------------------------------------------------------
Germanium                                   Manganese
------------------------------------------------------------------------
         Nine Pesticides Using EPA Method 525.3 (SPE GC/MS) \7\
------------------------------------------------------------------------
alpha-hexachlorocyclohexane                 Profenofos
chlorpyrifos                                Tebuconazole
Dimethipin                                  total permethrin (cis- &
                                             trans-)
Ethoprop                                    Tribufos
Oxyfluorfen
------------------------------------------------------------------------
 Three Brominated HAA Groups Using EPA Method 552.3 (GC/ECD) or 557 (IC/
                         ECI-MS/MS) \8\ \9\ \10\
------------------------------------------------------------------------
HAA5                                        HAA9
HAA6Br
------------------------------------------------------------------------
            Three Alcohols Using EPA Method 541 (GC/MS) \11\
------------------------------------------------------------------------
1-butanol                                   2-propen-1-ol
2-methoxyethanol
------------------------------------------------------------------------
 Three Semivolatile Organic Chemicals (SVOCs) Using EPA Method 530 (GC/
                                MS) \12\
------------------------------------------------------------------------
butylated hydroxyanisole                    quinolone
o-toluidine
------------------------------------------------------------------------
\1\ ELISA Standard Operating Procedure (SOP) (Ohio EPA, 2015). EPA
  anticipates having an EPA ELISA method available by the publication of
  the final rule and anticipates that this method will be similar to the
  Ohio EPA methodology. Monitoring includes measuring for pH using one
  of the following methods: EPA Method 150.1 and 150.2 (USEPA, 1983a and
  1983b), ASTM D1293-12 (ASTM, 2012a), SM 4500-H+ B (SM, 2005c), SM 4500-
  H+ B-00 (SM Online, 2000a). Monitoring also includes measuring for
  water temperature using one of the following methods: SM 2550 (SM,
  2005a) or SM 2550-10 (SM Online, 2010).
\2\ EPA Method 544 (Solid Phase Extraction (SPE) Liquid chromatography/
  tandem mass spectrometry (LC/MS/MS)) (USEPA, 2015f). This method would
  only be used if analyses by ELISA (for ``total microcystins'') yielded
  results above reporting limits.
\3\ EPA Method 545 (Liquid chromatography/electrospray ionization/tandem
  mass spectrometry (LC/ESI-MS/MS)) (USEPA, 2015g).
\4\ EPA Method 200.8 (Inductively coupled plasma mass spectrometry (ICP-
  MS)) (USEPA, 1994).
\5\ Standard Methods (SM) 3125 (SM, 2005b) or SM 3125-09 (SM Online,
  2009).
\6\ ASTM International (ASTM) D5673-10 (ASTM, 2010).
\7\ EPA Method 525.3 (SPE Gas chromatography/mass spectrometry (GC/MS))
  (USEPA, 2012a).
\8\ EPA Method 552.3 (GC/Electron capture detection (ECD)) (USEPA, 2003)
  and EPA Method 557 (Ion chromatography-electrospray ionization-tandem
  mass spectrometry (IC-ESI-MS/MS)) (USEPA, 2009b). HAA5 includes:
  dibromoacetic acid, dichloroacetic acid, monobromoacetic acid,
  monochloroacetic acid, trichloroacetic acid. HAA6Br includes:
  bromochloroacetic acid, bromodichloroacetic acid, dibromoacetic acid,
  dibromochloroacetic acid, monobromoacetic acid, tribromoacetic acid.
  HAA9 includes: bromochloroacetic acid, bromodichloroacetic acid,
  chlorodibromoacetic acid, dibromoacetic acid, dichloroacetic acid,
  monobromoacetic acid, monochloroacetic acid, tribromoacetic acid,
  trichloroacetic acid.
\9\ Regulated HAAs (HAA5) are included in the proposed monitoring
  program to gain a better understanding of co-occurrence with currently
  unregulated disinfection byproducts.
\10\ Brominated HAA monitoring also includes sampling for indicators TOC
  and bromide using methods approved for compliance monitoring. TOC
  methods include: SM 5310B, SM 5310C, SM 5310D (SM, 2005d, 2005e,
  2005f), or SM 5310B-00, SM 5310C-00, SM 5310D-00 (SM Online, 2000b,
  2000c, 2000d), EPA Method 415.3 (Rev. 1.1 or 1.2) (USEPA, 2005,
  2009a). Bromide methods include: EPA Methods 300.0 (Rev. 2.1), 300.1
  (Rev. 1.0), 317.0 (Rev. 2.0), 326.0 (Rev. 1.0) (USEPA, 1993, 1997,
  2001a, 2002) or ASTM D 6581-12 (ASTM, 2012b).
\11\ EPA Method 541 (GC/MS) (USEPA, 2015e).
\12\ EPA Method 530 (GC/MS) (USEPA, 2015d).

E. What is the proposed applicability date?

    EPA proposes (in Sec.  141.40(a)) a new applicability date of
December 31, 2015. That is, the determination of whether a PWS is
required to monitor under UCMR 4 is based on the type of system (e.g.,
CWS, NTNCWS, etc.) and its retail population served, as indicated by
the SDWIS/Fed inventory on December 31, 2015. If a PWS believes its
retail population served in SDWIS/Fed is inaccurate, the system should
contact its state to verify its population as of the applicability date
and request a correction if necessary. The 5-year UCMR 4 program would
take place from January 2017 through December 2021.

F. What are the proposed UCMR 4 sampling design and timeline of
activities?

    The proposed rule identifies sampling and analysis for List 1
contaminants within the 2018 to 2020 time frame. Preparations prior to
2018 are expected to include coordination of laboratory approval,
selection of representative small systems, development of SMPs and
establishment of monitoring schedules. EPA anticipates that there is
enough laboratory capacity to meet the needs of Assessment Monitoring.
Exhibit 4 illustrates the major activities that we expect will take
place in preparation for and during the implementation of UCMR 4.

                                Exhibit 4--Proposed Timeline of UCMR 4 Activities
----------------------------------------------------------------------------------------------------------------
               2017                       2018               2019               2020                2021
----------------------------------------------------------------------------------------------------------------
After proposed rule publication:             [larr] Assessment Monitoring [rarr]            Complete reporting
 EPA                                                                                and analysis of
 laboratory approval program                         List 1 Contaminants                     data.
 begins.
After final rule publication: EPA/    All large systems serving more than 10,000 people;
 state
 primacy authorities (1) develop       800 small systems serving 10,000 or fewer people
 SMPs
 (including the nationally                             for cyanotoxins;
 representa-
 tive sample); and (2) inform          800 small systems serving 10,000 or fewer people
 PWSs/
 establish monitoring plans.                   for the 20 additional chemicals.
----------------------------------------------------------------------------------------------------------------

    To minimize the impact of the rule on small systems (those serving
10,000 or fewer people), EPA pays for the sample kit preparation,
sample shipping fees and analysis costs for these systems. In addition,
no small system would be required to monitor for both cyanotoxins and
the 20 additional UCMR chemicals. Consistent with prior UCMRs, large
systems (those serving more than 10,000 people) pay for all costs
associated with their monitoring. A summary of the estimated number of
systems subject to monitoring is shown in Exhibit 5.

                             Exhibit 5--Systems To Participate in UCMR 4 Monitoring
----------------------------------------------------------------------------------------------------------------
                                                 National sample assessment monitoring
                                        ------------------------------------------------------  Total number of
 System size (number of people served)                                 20 Additional List 1     systems per size
                                           10 List 1 cyanotoxins            chemicals               category
----------------------------------------------------------------------------------------------------------------
Small Systems: \1\
    25-10,000..........................  800 randomly selected SW   800 randomly selected SW,              1,600
                                          or GWUDI systems.          GWUDI and GW systems.
Large Systems: \2\
    10,001 and over....................  All SW or GWUDI systems    All SW, GWUDI and GW                   4,292
                                          (1,987).                   systems (4,292).
                                        ------------------------------------------------------------------------
        Total..........................  2,787....................  5,092....................              5,892
----------------------------------------------------------------------------------------------------------------
\1\ Total for small systems is additive because these systems would only be selected for one component of UCMR 4
  sampling (10 cyanotoxins or 20 additional chemicals). EPA would pay for all analytical costs associated with
  monitoring at small systems.
\2\ Large system counts are approximate. The number of large systems is not additive. All SW and GWUDI systems
  would monitor for cyanotoxins; those same systems would also monitor for the 20 additional List 1 chemicals,
  as would the large GW systems.

1. Sampling Frequency, Timing
    The number of samples for SW, GWUDI and GW systems would generally
be consistent with those during prior UCMR cycles, with the exceptions
noted for the monitoring of cyanotoxins. Water systems would be
required to collect samples during the monitoring time frame of March
through November (excluding December, January and February). With the
exception of cyanotoxin monitoring, sampling would take place every two
months for SW and GWUDI systems (a total of four sampling events), and
at 6-month intervals for GW systems (a total of two sampling events).
For cyanotoxin monitoring, SW and GWUDI systems would collect samples
twice a month for four consecutive months (total of eight sampling
events). GW systems would be excluded from cyanotoxin monitoring.
    The Assessment Monitoring sampling time frame would take place
during the compressed period of March through November to better
reflect the times of year when contaminants are more likely to occur in
drinking water. Populations of cyanobacteria generally peak when water
temperature is highest (Graham et al., 2008). Seasonality of pesticide
occurrence in surface waters has been well documented, and generally
relates to the timing of pesticide applications in the watershed,
rainfall or irrigation patterns and watershed size (USGS, 2014; Ryberg
and Gilliom, 2015). Based on this information, EPA anticipates that
sampling in the December through February time period would not
accurately reflect occurrence for some of the contaminants,
particularly cyanotoxins and pesticides. Industry and laboratory
stakeholders have also observed that the traditional UCMR approach has
the potential to underestimate exposure for some contaminants because
of seasonal occurrence (Roberson and Eaton, 2014). Therefore, EPA is
proposing that no sampling take place during those winter months,
except for resampling purposes. EPA welcomes comments on this approach.
    Large system schedules (year and months of monitoring) would
initially be determined by EPA in conjunction

with the states (as described in section II.K) and these PWSs would
have an opportunity to modify this schedule for planning purposes or
other reasons (e.g., to conduct monitoring during the months the system
or the state believes are most vulnerable, spread costs over multiple
years, a sampling location will be closed during the scheduled month of
monitoring, etc.). PWSs would not be permitted to reschedule monitoring
specifically to avoid sample collection during a suspected vulnerable
period. EPA proposes to schedule and coordinate small system monitoring
by working closely with partnering states. SMPs provide an opportunity
for states to review and revise the initial sampling schedules that EPA
proposes (see discussion of SMPs in section II.K).
2. Sampling Locations
    Sample collection for the UCMR 4 contaminants would take place at
the entry point to the distribution system (EPTDS), with the following
exceptions/additions. Sampling for ``total microcystins'' (i.e., the
sum of congeners as measured by ADDA-ELISA) would also take place at
the source water intake (concurrent with the collection of cyanotoxin
samples at the EPTDS) unless the PWS purchases 100 percent of their
water. ``Consecutive systems'' would only sample for cyanotoxins at
their EPTDS. Measurements for temperature and pH would take place at
the source water intake (concurrent with total microcystin sampling).
HAA sampling would take place in the distribution system. Sampling for
TOC and bromide would take place at a single source water intake
(concurrent with HAA sampling in the distribution system). The
indicator data, along with the disinfectant type and water treatment
information, would aid in the understanding of brominated HAA and
cyanotoxin occurrence and treatment efficacy.
    For purposes of total microcystin sampling, temperature and pH
measurement, and TOC and bromide sampling, EPA defines source water
under UCMR as untreated water entering the water treatment plant (i.e.,
at a location prior to any treatment). Systems that are subject to the
Long Term 2 Enhanced Surface Water Treatment Rule (LT2) would use their
source water sampling site(s) that have been identified under that rule
(71 FR 654, January 5, 2006 (USEPA, 2006a)). Systems subject to the
Stage 1 Disinfectants and Disinfection Byproducts Rule (DBPR) would use
their TOC source water sampling site(s) (63 FR 69390, December 16, 1998
(USEPA, 1998c)). TOC source water sampling site(s) were set under Stage
1 DBPR and remain unchanged under Stage 2 DBPR. If a system has two
different source water sampling locations for LT2 and Stage 1 DBPR, the
system would be permitted to select the sample point that best
represents the definition of source water sample location(s) for UCMR.
    EPA proposes that PWSs monitor for HAAs only in the distribution
system. If the system's treatment plant/water source is subject to
sampling requirements under Sec.  141.622 (monitoring requirements for
Stage 2 DBPR), the water systems must collect samples for the HAAs at
the sampling locations identified under that rule (71 FR 388, January
4, 2006 (USEPA, 2006b)). If a treatment plant/water source is not
subject to Stage 2 DBPR monitoring, then the water system must collect
HAA distribution system samples at a location that represents the
DSMRT. UCMR 4 HAA samples and HAA5 Stage 2 DBPR compliance monitoring
samples may be collected by the PWS at the same time. However, in such
cases, PWSs would be required to arrange for UCMR 4 HAA samples to be
analyzed by a UCMR 4 approved laboratory using EPA Method 552.3 or 557
(compliance methods used for analysis of Stage 2 DBPR samples).
3. Phased Sample Analysis for Microcystins
    EPA is proposing a phased sample analysis approach for microcystins
to reduce analytical costs (i.e., PWSs must collect all required
samples for each sampling event but not all samples may need to be
analyzed). Two samples would be collected for ADDA ELISA (one source
water intake sample and one EPTDS), and one sample would be collected
for EPA Method 544 at the EPTDS. Initially, source water intake samples
(collected by ``non-consecutive'' SW and GWUDI PWSs) would be analyzed
for total microcystins as defined by an ADDA specific ELISA
methodology. ADDA ELISA is a widely used screening assay that allows
for the aggregate detection of numerous microcystin congeners; it does
not allow for measurement of the individual congeners (USEPA, 2015c;
Fischer et al., 2001; McElhiney and Lawton, 2005; Zeck et al., 2001).
If the source water intake ELISA result is less than 0.3 micrograms per
liter ([mu]g/L) (i.e., the reporting limit for total microcystins),
then the other collected samples (from the EPTDS) would not be analyzed
for that sample event and only the source water result would be
reported to EPA. If the ELISA result from the source water intake is
greater than or equal to 0.3 [mu]g/L, the result would be reported to
EPA and the sample from the EPTDS would then also be analyzed for total
microcystins by ELISA. ELISA analysis of the EPTDS sample would be the
first step for consecutive systems. If the EPTDS ELISA result is less
than 0.3 [mu]g/L, then no additional analyses would be required for
that particular sample event and the result would be reported to EPA.
If the EPTDS ELISA result is greater than or equal to 0.3 [mu]g/L, then
that result would be reported to EPA and the other microcystin sample
collected at the EPTDS would be analyzed using EPA Method 544 to
identify and quantify six particular microcystin congeners and a
related toxin, nodularin. Method 544 uses liquid chromatography with
tandem mass spectrometry (LC/MS/MS) to quantify and speciate
microcystin congeners at low concentrations. Using Method 544 to
analyze EPTDS samples that tested positive for microcystins by ELISA is
expected to help EPA and the states to establish the degree to which
particular congener occurrence compares with total microcystin
occurrence as measured by ADDA ELISA (USEPA, 2015c).
    This phased sample analysis approach for microcystins has the
potential to achieve significant cost savings. A similar approach is
not practical for cylindrospermopsin and anatoxin-a samples. Therefore,
EPA proposes that cylindrospermopsin and anatoxin-a sampling be
conducted simultaneously with the microcystins, twice a month for four
consecutive months only at the EPTDS, and that the samples be analyzed
using EPA Method 545.
4. Representative Sampling
    As during past UCMRs and as described in Sec.  141.35(c)(3), the
proposed rule would allow large GW systems that have multiple EPTDSs,
with prior approval, to sample at representative sampling locations
rather than at each EPTDS. Representative sampling plans approved under
prior UCMRs will be recognized as valid for UCMR 4 and these systems
must submit a copy of documentation from their state or EPA that
approves their alternative sampling plan. Any new GW representative
monitoring plans must be submitted to be reviewed by the state or EPA
within 120 days from publication of the final rule. Once approved,
these representative EPTDS locations, along with previously approved
EPTDS locations from prior UCMRs, must be loaded into the Safe Drinking
Water

Accession and Review System (SDWARS) by December 31, 2017.
5. Summary
    With the exception of the increased sample frequency, phased sample
analysis for microcystins, revised sampling locations and the
compressed monitoring schedule, the approach to UCMR 4 Assessment
Monitoring remains consistent with that established for UCMR 3.
    EPA invites comments regarding the cyanotoxin monitoring approach
and the usefulness of collecting temperature and pH data (concurrently
with the ELISA sample) at the source water intake, as well as
designating source water type (e.g., lakes/reservoirs or flowing
streams), as potential indicators of cyanotoxin occurrence. EPA also
invites comments on the appropriateness of other potential cyanotoxin
indicators, recognizing that the cost of any additional indicator
monitoring would need to be weighed with consideration given to the
likelihood of any other parameters serving as effective indicators.
    Finally, EPA recognizes the trade-off between PWS burden and
occurrence-data representativeness, and has attempted to strike a
reasonable balance in selecting the affected PWSs and establishing the
monitoring frequency. The Agency welcomes comment on this particular
point, including input regarding the appropriateness of collecting
occurrence data from fewer PWSs. This could include employing the
Screening Survey approach used in UCMR 3 or an alternative design. EPA
requests that commenters suggesting alternatives describe how their
proposed approach would be nationally representative of the frequency
and level of contaminant occurrence.

G. What are reporting requirements for UCMR 4?

1. Data Elements
    EPA proposes the following changes to the reporting requirements
listed in Table 1 of Sec.  141.35(e) to account for the UCMR 4
contaminants being proposed and the associated indicators.
Additionally, EPA proposes to collect quality control information
related to sample analysis. This information would further ensure that
methods are followed as written, and would provide continuous quality
assurance of data reported. EPA collected this information for small
systems in previous UCMRs and found that doing so helps ensure that
laboratories consistently follow the methods.
     Add Public Water System Name. New data element to be
assigned once by the PWS.
     Add Public Water System Facility Name. New data element to
be assigned once by the PWS for every facility identification code.
     Add Public Water System Facility Type. New data element to
be assigned once by the PWS for every facility.
     Update Sampling Point Identification Code. Added ``source
water'' as an example of applicable sampling locations.
     Add Sampling Point Name. New data element to be assigned
once by the PWS for every sampling point identification code.
     Update Sample Point Type Code. Add source water (SR) to
account for brominated HAA indicators and microcystin monitoring at the
intake to the treatment plant.
     Update Disinfectant Type. Adding the following primary
disinfectant/oxidation practices: Permanganate applied before SR sample
location (PEMB) and after (PEMA), hydrogen peroxide applied before SR
sample location (HPXB) and after (HPXA), and chlorine dioxide applied
before SR sample location (CLDB) and after (CLDA).
     Add Treatment Information. New data element to capture
treatment associated with the water being sampled.
     Add Disinfectant Residual Type. New data element to
capture disinfectant residual type information associated with the
water being sampled.
     Add Extraction Batch Identification Code. New data element
to allow evaluation of quality control elements associated with
extraction of samples in methods where extraction is required.
     Add Extraction Date. New data element identifying the date
of sample extraction.
     Add Analysis Batch Identification Code. New data element
to allow evaluation of quality control elements associated with
analyzing samples.
     Add Analysis Date. New data element identifying the start
date of sample analysis.
     Update Sample Analysis Type. The following elements are
proposed as quality assurance measures:
    [cir] Continuing calibration check (CCC), an element that verifies
the accuracy of method calibration;
    [cir] Internal standard (IS), an element that measures the relative
response of contaminants;
    [cir] Laboratory fortified blank (LFB), an element that verifies
method performance in the absence of a sample matrix;
    [cir] Laboratory reagent blank (LRB), an element that verifies the
absence of interferences in the reagents and equipment;
    [cir] Quality control sample (QCS), an element that verifies the
accuracy of the calibration standards;
    [cir] Quality HAA (QH), HAA sample collected and submitted for
quality control; and,
    [cir] Surrogate standard (SUR), an element that assesses method
performance for each extraction.
     Update Analytical Result--Value. Update to ``Analytical
Result--Measured Value.'' The measured value is the analytical result
for the contaminant.
     Add Additional Value. This element is used for quality
control samples and is the amount of contaminant added to a QCS.
     Update Sample Event Code. Revise sample event codes to
uniquely identify sampling events with specific codes for cyanotoxin
and additional chemical monitoring.
2. Duplicate Samples
    Currently, Sec.  141.40(a)(4)(ii)(F), requires EPA to randomly
select a small percentage of small water systems to collect duplicate
water samples for quality control purposes. Based on experience from
previous UCMRs, this requirement did not provide significant useful
information and EPA proposes to remove the requirement for the
collection of duplicate samples from UCMR 4.

H. What are Minimum Reporting Levels (MRLs) and how were they
determined?

    The analyte minimum reporting level (MRL) is a quantitation level
designed to be an estimate of the reporting level that is achievable,
with 95% confidence, by a capable analyst/laboratory at least 75% of
the time, using the prescribed method. Demonstration of the ability to
reliably make quality measurements at or below the MRL is intended to
ensure that high quality results are being reported by participating
laboratories. MRLs are generally established as low as is reasonable
(and are typically lower than the current health reference levels and
health advisories), so that the occurrence data reported to EPA will
support sound decision making, including those cases where new
information might lead to lower health reference levels. EPA
established the proposed MRL for each analyte/method by obtaining data
from several laboratories performing ``lowest concentration minimum
reporting level'' (LCMRL) studies. For further information on the LCMRL
and MRL

process, see ``Technical Basis for the Lowest Concentration Minimum
Reporting Level (LCMRL) Calculator'' (USEPA, 2010), available on the
Internet at (http://www2.epa.gov/dwanalyticalmethods/approved-drinking-water-analytical-methods). EPA will consider raising MRLs if the Agency
becomes aware of evidence that a proposed MRL is unattainable or
impractical.

I. How do laboratories become approved to conduct UCMR 4 analyses?

    The proposed rule would require EPA approval for all laboratories
conducting analyses for UCMR 4. EPA anticipates following the
traditional Agency approach to approving UCMR laboratories, which would
require laboratories seeking approval to: (1) Provide EPA with data
that demonstrate a successful completion of an initial demonstration of
capability (IDC) as outlined in each method; (2) verify successful
performance at or below the MRLs as specified in this action; (3)
provide information about laboratory operating procedures; and (4)
successfully participate in an EPA proficiency testing (PT) program for
the analytes of interest. Audits of laboratories may be conducted by
EPA prior to and/or following approval. The ``UCMR 4 Laboratory
Approval Requirements and Information Document'' (USEPA, 2015j) will
provide guidance on the EPA laboratory approval program and the
specific method acceptance criteria.
    EPA may supply analytical reference standards for select analytes
to participating/approved laboratories when reliable standards are not
readily available through commercial sources.
    The structure of the proposed UCMR 4 laboratory approval program is
the same as that employed in previous UCMRs, and would provide an
assessment of the ability of laboratories to perform analyses using the
methods listed in Sec.  141.40(a)(3), Table 1. The UCMR 4 laboratory
approval process is designed to assess whether laboratories possess the
required equipment and can meet laboratory-performance and data-
reporting criteria described in this action. Laboratory participation
in the UCMR laboratory approval program is voluntary. However, as in
previous UCMRs and as proposed for UCMR 4, EPA would require PWSs to
exclusively use laboratories that have been approved under the program.
EPA expects to post a list of approved UCMR 4 laboratories to: http://www2.epa.gov/dwucmr. Laboratories are encouraged to apply for UCMR 4
approval as early as possible, as EPA anticipates that large PWSs
scheduled for monitoring in the first year will be making arrangements
for sample analyses soon after the final rule is published. The
anticipated steps and requirements for the laboratory approval process
are listed in the following paragraphs, steps 1 through 6.
1. Request To Participate
    Laboratories interested in the UCMR 4 laboratory approval program
would first email EPA at<EMAIL_ADDRESS>to request
registration materials. EPA expects to accept such requests beginning
December 11, 2015. EPA anticipates that the final opportunity for a
laboratory to complete and submit the necessary registration
information will be 60 days after final rule publication.
2. Registration
    Laboratory applicants provide registration information that
includes: laboratory name, mailing address, shipping address, contact
name, phone number, email address and a list of the UCMR 4 methods for
which the laboratory is seeking approval. This registration step
provides EPA with the necessary contact information, and ensures that
each laboratory receives a customized application package.
3. Application Package
    Laboratories that wish to participate complete and return a
customized application package that includes the following: IDC data,
including precision, accuracy and results of MRL studies; information
regarding analytical equipment and other materials; proof of current
drinking water laboratory certification (for select compliance
monitoring methods); and example chromatograms for each method under
review.
    As a condition of receiving and maintaining approval, the
laboratory is expected to confirm that it will post UCMR 4 monitoring
results and quality control data that meet method criteria (on behalf
of its PWS clients) to EPA's UCMR electronic data reporting system,
SDWARS.
4. EPA's Review of Application Package
    EPA will review the application packages and, if necessary, request
follow-up information. Laboratories that successfully complete the
application process become eligible to participate in the UCMR 4 PT
program.
5. Proficiency Testing
    A PT sample is a synthetic sample containing a concentration of an
analyte or mixture of analytes that is known to EPA, but unknown to the
laboratory. To be approved, a laboratory is expected to meet specific
acceptance criteria for the analysis of a UCMR 4 PT sample(s) for each
analyte in each method, for which the laboratory is seeking approval.
EPA intends to offer up to four opportunities for a laboratory to
successfully analyze UCMR 4 PT samples. Up to three of these studies
will be conducted prior to the publication of the final rule, and at
least one study will be conducted after publication of the final rule.
This allows laboratories to complete their portion of the laboratory
approval process prior to publication of the final rule and receive
their approval immediately following the publication of the final rule.
A laboratory is expected to pass one of the PT studies for each
analytical method for which it is requesting approval, and will not be
required to pass a PT study for a method it already passed in a
previous UCMR 4 PT study. EPA does not expect to conduct additional PT
studies after the start of system monitoring; however, laboratory
audits will likely be ongoing throughout UCMR 4 implementation. Initial
laboratory approval is expected to be contingent on successful
completion of a PT study. Continued laboratory approval is contingent
on successful completion of the audit process and satisfactorily
meeting all the other stated conditions.
6. Written EPA Approval
    After successfully completing the preceding steps 1 through 5, EPA
expects to send each laboratory a letter listing the methods for which
approval is pending (i.e., pending promulgation of the final rule if
the PT studies have been conducted prior to that time), or for which
approval is granted (if after promulgation of the final rule).
Laboratories receiving pending approval are expected to be granted
approval without further action following promulgation of the final
rule if no changes have been made to the rule that impact the
laboratory approval program. EPA expects to contact the laboratory if
changes are made between the proposed and final rules that warrant
additional action by the laboratory.

J. What documents are being incorporated by reference?

    The following methods are being incorporated by reference into this
section for UCMR 4 monitoring. All approved material except for the
Standard Method Online, is available for inspection electronically at
http://www.regulations.gov (Docket ID No. OW-2015-0218), or from the
sources listed for each method. EPA has worked to make these methods
and documents

reasonably available to interested parties. The versions of the EPA and
non-EPA methods that may be used to support monitoring under this rule
are as follows:
1. Methods From the U.S. Environmental Protection Agency
    The following methods are from the U.S. Environmental Protection
Agency, Water Docket, EPA/DC, EPA West, Room 3334, 1301 Constitution
Avenue NW., Washington, DC 20004.
    (i) EPA Method 150.1 ``pH Electrometric, in Methods for Chemical
Analysis of Water and Wastes,'' 1983, EPA/600/4-79/020. Available on
the Internet at http://www.nemi.gov. This is an EPA method for
measuring pH in water samples using a meter with a glass electrode and
reference electrode or a combination electrode. The proposal includes
measurement of pH as a potential indicator for cyanotoxins.
    (ii) EPA Method 150.2 ``pH, Continuous Monitoring (Electrometric),
in Methods for Chemical Analysis of Water and Wastes,'' 1983, EPA/600/
4-79/020. Available on the Internet at http://www.nemi.gov. This is an
EPA method for measuring pH of in-line water samples using a continuous
flow meter with a glass electrode and reference electrode or a
combination electrode.
    (iii) EPA Method 200.8 ``Determination of Trace Elements in Waters
and Wastes by Inductively Coupled Plasma--Mass Spectrometry,'' Revision
5.4, 1994. Available on the Internet at https://www.nemi.gov. This is
an EPA method for the analysis of elements in water by ICP-MS and is
proposed to measure germanium and manganese.
    (iv) EPA Method 300.0 ``Determination of Inorganic Anions by Ion
Chromatography Samples,'' Revision 2.1, 1993. Available on the Internet
at http://www.nemi.gov. This is an EPA method for the analysis of
inorganic anions in water samples using ion chromatography (IC) with
conductivity detection. The proposal includes measurement of bromide as
a potential indicator for HAAs.
    (v) EPA Method 300.1 ``Determination of Inorganic Anions in
Drinking Water by Ion Chromatography,'' Revision 1.0, 1997. Available
on the Internet at http://www2.epa.gov/dwanalyticalmethods/approved-drinking-water-analytical-methods. This is an EPA method for the
analysis of inorganic anions in water samples using IC with
conductivity detection.
    (vi) EPA Method 317.0 ``Determination of Inorganic Oxyhalide
Disinfection By-Products in Drinking Water Using Ion Chromatography
with the Addition of a Postcolumn Reagent for Trace Bromate Analysis,''
Revision 2.0, 2001, EPA 815-B-01-001. Available on the Internet at
http://www2.epa.gov/dwanalyticalmethods/approved-drinking-water-analytical-methods. This is an EPA method for the analysis of inorganic
anions in water samples using IC with conductivity detection.
    (vii) EPA Method 326.0 ``Determination of Inorganic Oxyhalide
Disinfection By-Products in Drinking Water Using Ion Chromatography
Incorporating the Addition of a Suppressor Acidified Postcolumn Reagent
for Trace Bromate Analysis,'' Revision 1.0, 2002, EPA 815-R-03-007.
Available on the Internet at http://www2.epa.gov/dwanalyticalmethods/approved-drinking-water-analytical-methods. This is an EPA method for
the analysis of inorganic anions in water samples using IC with
conductivity detection.
    (viii) EPA Method 415.3 ``Determination of Total Organic Carbon and
Specific UV Absorbance at 254 nm in Source Water and Drinking Water,''
Revision 1.1, 2005, EPA/600/R-05/055. Available on the Internet at
http://www2.epa.gov/water-research/epa-drinking-water-research-methods.
This is an EPA method for the analysis of TOC in water samples using a
conductivity detector or a nondispersive infrared detector.
    (ix) EPA Method 415.3 ``Determination of Total Organic Carbon and
Specific UV Absorbance at 254 nm in Source Water and Drinking Water,''
Revision 1.2, 2009, EPA/600/R-09/122.Available on the Internet at
http://www2.epa.gov/water-research/epa-drinking-water-research-methods.
This is an EPA method for the analysis of TOC in water samples using a
conductivity detector or a nondispersive infrared detector.
    (x) EPA Method 525.3 ``Determination of Semivolatile Organic
Chemicals in Drinking Water by Solid Phase Extraction and Capillary
Column Gas Chromatography/Mass Spectrometry (GC/MS),'' Version 1.0,
February 2012, EPA/600/R-12/010. Available on the Internet at http://www2.epa.gov/water-research/epa-drinking-water-research-methods. This
is an EPA method for the analysis of semivolatile organic chemicals in
drinking water using SPE and GC/MS and is proposed to measure nine
pesticides (alpha-hexachlorocyclohexane, chlorpyrifos, dimethipin,
ethoprop, oxyfluorfen, profenofos, tebuconazole, total cis- and trans-
permethrin, and tribufos).
    (xi) EPA Method 530 ``Determination of Select Semivolatile Organic
Chemicals in Drinking Water by Solid Phase Extraction and Gas
Chromatography/Mass Spectrometry (GC/MS),'' Version 1.0, January 2015,
EPA/600/R-14/442. Available on the Internet at http://www2.epa.gov/water-research/epa-drinking-water-research-methods. This is an EPA
method for the analysis of semivolatile organic chemicals in drinking
water using SPE and GC/MS and is proposed to measure butylated
hydroxyanisole, o-toluidine, and quinoline.
    (xii) EPA Method 541 ``Determination of 1-Butanol, 1,4-Dioxane, 2-
Methoxyethanol and 2-Propen-1-ol in Drinking Water by Solid Phase
Extraction and Gas Chromatography/Mass Spectrometry,'' November 2015,
EPA 815-R-15-011. Available on the Internet at http://www2.epa.gov/dwanalyticalmethods/approved-drinking-water-analytical-methods. This is
an EPA method for the analysis of selected alcohols and 1,4-dioxane in
drinking water using SPE and GC/MS and is proposed to measure 1-
butanol, 2-methoxyethanol and 2-propen-1-ol.
    (xiii) EPA Method 544 ``Determination of Microcystins and Nodularin
in Drinking Water by Solid Phase Extraction and Liquid Chromatography/
Tandem Mass Spectrometry (LC/MS/MS),'' Version 1.0, February 2015, EPA/
600/R-14/474. Available on the Internet at http://www2.epa.gov/water-research/epa-drinking-water-research-methods. This is an EPA method for
the analysis of selected cyanotoxins in drinking water using SPE and
LC-MS/MS with electrospray ionization (ESI) and is proposed to measure
six microcystins (microcystin-LA, microcystin-LF, microcystin-LR,
microcystin-LY, microcystin-RR, and microcystin-YR) and nodularin.
    (xiv) EPA Method 545 ``Determination of Cylindrospermopsin and
Anatoxin-a in Drinking Water by Liquid Chromatography Electrospray
Ionization Tandem Mass Spectrometry (LC/ESI-MS/MS),'' April 2015, EPA
815-R-15-009. Available on the Internet at http://www2.epa.gov/dwanalyticalmethods/approved-drinking-water-analytical-methods. This is
an EPA method for the analysis of selected cyanotoxins in drinking
water using LC-MS/MS with electrospray ionization (ESI) and is proposed
to measure cylindrospermopsin and anatoxin-a.
    (xv) EPA Method 552.3 ``Determination of Haloacetic Acids and
Dalapon in Drinking Water by Liquid-Liquid Microextraction,
Derivatization,

and Gas Chromatography with Electron Capture Detection,'' Revision 1.0,
July 2003, EPA 815-B-03-002. Available on the Internet at http://www2.epa.gov/dwanalyticalmethods/approved-drinking-water-analytical-methods. This is an EPA method for the analysis of haloacetic acids and
dalapon in drinking water using liquid-liquid microextraction,
derivatization, and GC with electron capture detection (ECD) and is
proposed to measure three HAA groups (HAA5, HAA6Br and HAA9).
    (xvi) EPA Method 557 ``Determination of Haloacetic Acids, Bromate,
and Dalapon in Drinking Water by Ion Chromatography Electrospray
Ionization Tandem Mass Spectrometry (IC-ESI-MS/MS),'' Version 1.0,
September 2009, EPA 815-B-09-012. Available on the Internet at http://www2.epa.gov/dwanalyticalmethods/approved-drinking-water-analytical-methods. This is an EPA method for the analysis of haloacetic acids,
bromate, and dalapon in drinking water using IC-MS/MS with electrospray
ionization (ESI) and is proposed to measure three HAA groups (HAA5,
HAA6Br and HAA9).
2. Methods From ``ASTM International''
    The following methods are from ``ASTM International'', 100 Barr
Harbor Drive, West Conshohocken, PA 19428-2959.
    (i) ASTM D1293-12 ``Standard Test Methods for pH of Water.''
Available for purchase on the Internet at http://www.astm.org/Standards/D1293.htm. This is an ASTM method for measuring pH in water
samples using a meter and associated electrodes.
    (ii) ASTM D5673-10 ``Standard Test Method for Elements in Water by
Inductively Coupled Plasma-Mass Spectrometry,'' approved August 1,
2010. Available for purchase on the Internet at http://www.astm.org/Standards/D5673.htm. This is an ASTM method for the analysis of
elements in water by ICP-MS and is proposed to measure germanium and
manganese.
    (iii) ASTM D6581-12 ``Standard Test Methods for Bromate, Bromide,
Chlorate, and Chlorite in Drinking Water by Suppressed Ion
Chromatography.'' Available for purchase on the Internet at http://www.astm.org/Standards/D6581.htm. This is an ASTM method for the
analysis of inorganic anions in water samples using IC with
conductivity detection. The proposal includes measurement of bromide as
a potential indicator for HAAs.
3. Methods From ``Standard Methods for the Examination of Water &
Wastewater''
    The following methods are from ``Standard Methods for the
Examination of Water & Wastewater'', 21st edition (2005), American
Public Health Association, 800 I Street NW., Washington, DC 20001-3710.
    (i) SM 2550 ``Temperature.'' This is a Standard Method for
temperature measurements using a thermometer (mercury). The proposal
includes measurement of temperature as a potential indicator for
cyanotoxins.
    (ii) SM 3125 ``Metals by Inductively Coupled Plasma/Mass
Spectrometry.'' This is a Standard Method for the analysis of metals
and metalloids in water by ICP-MS and is proposed for the analysis of
germanium and manganese.
    (iii) SM 4500-H+ B ``pH Value in Water by Potentiometry Using a
Standard Hydrogen Electrode.'' This is a Standard Method for measuring
pH of water samples using a meter, standard hydrogen electrode, and
reference electrode.
    (iv) SM 5310B ``The Determination of Total Organic Carbon by High-
Temperature Combustion Method.'' This is a Standard Method for the
analysis of TOC in water samples using a a conductivity detector or a
nondispersive infrared detector.
    (v) SM 5310C ``Total organic carbon by Persulfate-UV or Heated-
Persulfate Oxidation Method.'' This is a Standard Method for the
analysis of TOC in water samples using conductivity detector or a
nondispersive infrared detector.
    (vi) SM 5310D ``Total organic carbon by Wet-Oxidation Method.''
This is a Standard Method for the analysis of TOC in water samples
using a conductivity detector or a nondispersive infrared detector.
4. Methods From ``Standard Methods Online''
    The following methods are from ``Standard Methods Online,''
available for purchase on the Internet at http://www.standardmethods.org.
    (i) SM 2550-10 ``Temperature.'' This is a Standard Method for
temperature measurements using a thermometer (fluid filled or
electronic).
    (ii) SM 3125-09 ``Metals by Inductively Coupled Plasma/Mass
Spectrometry (Editorial revisions, 2011).'' This is a Standard Method
for the analysis of metals and metalloids in water by ICP-MS and is
proposed to measure germanium and manganese.
    (iii) SM 4500-H+ B-00 ``pH Value in Water by Potentiometry Using a
Standard Hydrogen Electrode.'' This is a Standard Method for measuring
pH in water samples using a meter, standard hydrogen electrode, and
reference electrode.
    (iv) SM 5310B-00 ``The Determination of Total Organic Carbon by
High-Temperature Combustion Method.'' This is a Standard Method for the
analysis of TOC in water samples using a conductivity detector or a
nondispersive infrared detector.
    (v) SM 5310C-00 ``Total organic carbon by Persulfate-UV or Heated-
Persulfate Oxidation Method.'' This is a Standard Method for the
analysis of TOC in water samples using a conductivity detector or a
nondispersive infrared detector.
    (vi) SM 5310D-00 ``Total organic carbon by Wet-Oxidation Method.''
This is a Standard Method for the analysis of TOC in water samples
using a conductivity detector or a nondispersive infrared detector.
5. Method From ``Ohio EPA''
    The following methodology is from Ohio EPA, Columbus, OH.
    (i) ELISA SOP ``Ohio EPA Total (Extracellular and Intracellular)
Microcystins--ADDA by ELISA Analytical Methodology,'' Version 2.0.
January 2015, available on the Internet at http://www.epa.ohio.gov/Portals/28/documents/habs/HAB_Analytical_Methodology.pdf. This is an
Ohio EPA method for the analysis of cyanotoxins (microcystins and
nodularin) in drinking water using an ELISA technique. The proposal
includes measurement of ``total microcystins'' using this technique.

K. What is the states' role in the UCMR program?

    UCMR is a direct implementation rule (i.e., EPA has primary
responsibility for its implementation) and state participation is
voluntary. Under previous UCMRs, specific activities that individual
states, tribes and territories agreed to carry out or assist with were
identified and established exclusively through Partnership Agreements
(PAs). Through PAs, states, tribes and territories can help EPA
implement the UCMR program and help ensure that the UCMR data are of
the highest quality possible to best support Agency decision making.
Under UCMR 4, EPA expects to continue to use the PA process to
determine and document the following: The process for review and
revision of the SMPs; replacing and updating system information; review
and approval of proposed ground water representative monitoring plans;
notification and instructions for

systems; and compliance assistance. EPA recognizes that states/primacy
agencies often have the best information about PWSs in their state and
encourages states to partner.
    SMPs include tabular listings of the systems that EPA selected and
the proposed schedule for their monitoring. Initial SMPs also typically
include instructions to states for revising and/or correcting system
information in the SMPs, including modifying the sampling schedules for
small systems. EPA expects to incorporate revisions from states,
resolve any outstanding questions and return the final SMPs to each
state.

L. What stakeholder meetings have been held in preparation for UCMR 4?

    EPA incorporates stakeholder involvement into each UCMR cycle.
Specific to the development of UCMR 4, EPA held two public stakeholder
meetings and is announcing a third in this proposal (see sections II.L
and II.M). EPA held a meeting focused on drinking water methods for CCL
contaminants on May 15, 2013, in Cincinnati, Ohio. Participants
included representatives of state agencies, laboratories, PWSs,
environmental organizations and drinking water associations. Meeting
topics included an overview of the regulatory process (CCL, UCMR and
Regulatory Determination) and drinking water methods under development,
primarily for CCL contaminants (see USEPA, 2013 for presentation
materials). EPA held a second stakeholder meeting on June 25, 2014, in
Washington, DC. Attendees representing state agencies, tribes,
laboratories, PWSs, environmental organizations and drinking water
associations participated in the meeting via webinar and in person.
Meeting topics included a status update on UCMR 3; UCMR 4 potential
sampling design changes relative to UCMR 3; UCMR 4 candidate analytes
and rationale; and the laboratory approval process (see USEPA, 2014 for
meeting materials).

M. How do I participate in the upcoming stakeholder meeting?

    EPA will hold the third public stakeholder meeting (via webinar) on
January 13, 2016. Topics will include the proposed UCMR 4 monitoring
requirements, analyte selection and rationale, analytical methods, the
laboratory approval process and ground water representative monitoring
plans.
1. Webinar Participation
    Those who wish to participate in the public webinar must register
in advance no later than 5:00 p.m., eastern time on January 10, 2016,
https://attendee.gotowebinar.com/register/7326881974233959170. To
ensure adequate time for public statements, individuals or
organizations interested in making a statement should identify their
interest when they register. We ask that only one person present on
behalf of a group or organization, and that the presentation be limited
to ten minutes. Any additional statements from attendees will be taken
during the webinar if time permits; alternatively, official comments
can be submitted to the docket. The number of webinar connections
available for the meeting is limited and will be available on a first-
come, first-served basis. Further details about registration and
participation in the webinar can be found on EPA's Unregulated
Contaminant Monitoring Program Meetings and Materials Web page at
http://www2.epa.gov/dwucmr/unregulated-contaminant-monitoring-rule-ucmr-meetings-and-materials.
2. Webinar Materials
    Meeting materials are expected to be sent by email to all
registered attendees prior to the public webinar. EPA will post the
materials on the Agency's Web site for persons who are unable to attend
the webinar. Please note, these materials could be posted after the
webinar.

N. How did EPA consider Children's Environmental Health?

    Executive Order 13045 does not apply to UCMR 4, however, EPA's
Policy on Evaluating Health Risks to Children is applicable (See III.G.
Executive Order 13045). By monitoring for unregulated contaminants that
may pose health risks via drinking water, UCMR furthers the protection
of public health for all citizens, including children. EPA considered
children's health risks during the proposed rule development process
for UCMR 4, including the decision-making process for prioritizing
candidate contaminants, and included a representative from EPA's Office
of Children's Health Protection as a participant on the UCMR 4
workgroup.
    The objective of UCMR 4 is to collect nationally representative
drinking water data on a set of unregulated contaminants. Wherever
feasible, EPA collects occurrence data for contaminants at levels below
current ``reference concentrations'' (e.g., health advisories and
health reference levels). By setting reporting levels as low as we
reasonably can, the Agency positions itself to better address updated
risk information in the future, including that associated with unique
risks to children. EPA requests comments regarding any further steps
that may be taken to evaluate and address health risks to children
within the scope of UCMR 4.

O. How did EPA address Environmental Justice?

    EPA did not identify any disproportionately high or adverse human
health or environmental effects on minority, low-income or indigenous
populations in the process of developing the proposed rule for UCMR 4
(See III.J. Executive Order 12898). By seeking to identify unregulated
contaminants that may pose health risks via drinking water from all
PWSs, UCMR furthers the protection of public health for all citizens.
EPA recognizes that unregulated contaminants in drinking water are of
interest to all populations and structured the rulemaking process and
implementation of the proposed UCMR 4 rule to allow for meaningful
involvement and transparency. EPA organized public meetings/webinars to
share information regarding the development of UCMR 4; coordinated with
tribal governments; and convened a workgroup with representatives from
the EPA Regions, EPA Program Offices, EPA's Office of Research and
Development and several states.
    EPA proposes to continue to collect U.S. Postal Service Zip Codes
for each PWS's service area, as collected under UCMR 3, to support an
assessment of whether or not minority, low-income and/or indigenous-
population communities are uniquely impacted by particular drinking
water contaminants. EPA solicits comment on additional actions the
Agency could take to further address environmental justice within the
UCMR program. EPA welcomes, for example, comments regarding sampling
and/or modeling approaches, and the feasibility and utility of applying
these approaches to determine disproportionate impacts.

III. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review and Executive
Order 13563: Improving Regulation and Regulatory Review

    This action is not a significant regulatory action and was
therefore not submitted to OMB.

B. Paperwork Reduction Act (PRA)

    The information collection activities in this proposed rule have
been submitted for approval to OMB under the PRA. The ICR document that
the EPA prepared has been assigned EPA ICR number 2192.07. You can find
a

copy of the ICR in the docket for this rule, and it is briefly
summarized here.
    The information that EPA proposes to collect under this rule
fulfills the statutory requirements of section 1445(a)(2) of SDWA, as
amended in 1996. The data will describe the source of the water,
location and test results for samples taken from PWSs. The information
collected will support Agency decisions as to whether or not to
regulate particular contaminants under SDWA. Reporting is mandatory.
The data are not subject to confidentiality protection.
    The annual burden and cost estimates described in this section are
based on the implementation assumptions described in section II.F.
Respondents to UCMR 4 include 1,600 small PWSs (800 for cyanotoxin
monitoring and a different set of 800 for monitoring the additional 20
chemicals), the ~4,292 large PWSs and the 56 states and primacy
agencies (~5,948 total respondents). The frequency of response varies
across respondents and years. System costs (particularly laboratory
analytical costs) vary depending on the number of sampling locations.
For cost estimates, EPA assumed that systems would conduct sampling
evenly across March 2018 through November 2020, excluding December,
January or February of each year, except for resampling purposes (i.e.,
one-third of the systems in each year of monitoring). Because the
applicable ICR period is 2017-2019, one year of monitoring activity
(i.e., 2020) is not captured in the ICR estimates; this will be
addressed in a subsequent ICR renewal for UCMR 4.
    Small PWSs that are selected for UCMR 4 monitoring would sample an
average of 6.7 times per PWS (i.e., number of responses per PWS) across
the 3-year ICR period. The average burden per response for small PWSs
is estimated to be 2.8 hours. Large PWSs (those serving 10,001 to
100,000 people) and very large PWSs (those serving more than 100,000
people) would sample and report an average of 11.4 and 14.1 times per
PWS, respectively, across the 3-year ICR period. The average burden per
response for large and very large PWSs is estimated at 6.1 and 9.9
hours, respectively. States are assumed to have an annual average
burden of 366.5 hours related to coordination with EPA and PWSs. In
aggregate, during the ICR period, the average response (e.g., responses
from PWSs and states) is associated with a burden of 6.9 hours, with a
labor plus non-labor cost of $1,705 per response.
    The annual average per-respondent burden hours and costs for the
ICR period are: Small PWSs--6.2 hours, or $171, for labor; large PWSs--
23.3 hours, or $682, for labor, and $6,047 for analytical costs; very
large PWSs--46.5 hours, or $1,248, for labor, and $16,298 for
analytical costs; and states--244.3 hours, or $11,598, for labor.
Annual average burden and cost per respondent (including both systems
and states) is estimated to be 23.4 hours, with a labor plus non-labor
cost of $3,470 per respondent. Burden is defined at 5 CFR 1320.3(b).
    An agency may not conduct or sponsor, and a person is not required
to respond to, a collection of information unless it displays a
currently valid OMB control number. The OMB control numbers for EPA's
rules in 40 CFR are listed in 40 CFR part 9.
    To comment on the Agency's need for this information, accuracy of
the burden estimates or to provide suggested methods for minimizing
respondent burden, reference the public docket for this rule, which
includes the ICR. Submit any comments related to the ICR to EPA and
OMB. See the ADDRESSES section at the beginning of this notice for
where to submit comments to EPA and OMB. OMB is required to make a
decision concerning the ICR between 30 and 60 days after December 11,
2015. Comments should be sent to OMB by January 11, 2016 for the
comment to be appropriately considered. The final rule will contain
responses to any OMB or public comments on the information collection
requirements contained in this proposal.

C. Regulatory Flexibility Act (RFA)

    For purposes of assessing the impacts of this proposed rule on
small entities, EPA considered small entities to be PWSs serving 10,000
or fewer people, because this is the system size specified in SDWA as
requiring special consideration with respect to small system
flexibility. As required by the RFA, EPA proposed using this
alternative definition in the FR, (63 FR 7606, February 13, 1998
(USEPA, 1998b)), requested public comment, consulted with the Small
Business Administration and finalized the alternative definition in the
Consumer Confidence Reports rulemaking, (63 FR 44512, August 19, 1998
(USEPA, 1998a)). As stated in that Final Rule, the alternative
definition would be applied to future drinking water rules, including
this rule.
    The evaluation of the overall impact on small systems, summarized
in the preceding discussion, is further described as follows. EPA
analyzed the impacts for privately-owned and publicly-owned water
systems separately, due to the different economic characteristics of
these ownership types, such as different rate structures and profit
goals. However, for both publicly- and privately-owned systems, EPA
used the ``revenue test,'' which compares annual system costs
attributed to the rule to the system's annual revenues. EPA used median
revenue data from the 2006 CWS Survey for public and private water
systems. The revenue figures were updated to 2014 dollars, and to
account for 3 percent inflation. EPA assumes that the distribution of
the sample of participating small systems will reflect the proportions
of publicly- and privately-owned systems in the national inventory. The
estimated distribution of the representative sample, categorized by
ownership type, source water and system size, is presented in Exhibit
6.

               Exhibit 6--Number of Publicly- and Privately-Owned Small Systems Subject to UCMR 4
----------------------------------------------------------------------------------------------------------------
              System size (number of people served)                 Publicly-owned    Privately-owned  Total \1\
----------------------------------------------------------------------------------------------------------------
                                                  Ground Water
----------------------------------------------------------------------------------------------------------------
500 and under....................................................                21                64         85
501 to 3,300.....................................................               161                62        223
3,301 to 10,000..................................................               179                41        220
                                                                  ----------------------------------------------
    Subtotal GW..................................................               361               167        528
----------------------------------------------------------------------------------------------------------------
                                            Surface Water (and GWUDI)
----------------------------------------------------------------------------------------------------------------
500 and under....................................................                18                21         39

501 to 3,300.....................................................               241                86        327
3,301 to 10,000..................................................               548               158        706
                                                                  ----------------------------------------------
    Subtotal SW..................................................               807               265      1,072
                                                                  ----------------------------------------------
        Total of Small Water Systems.............................             1,168               432      1,600
----------------------------------------------------------------------------------------------------------------
\1\ PWS counts were adjusted to display as whole numbers in each size category.

    The basis for the proposed UCMR 4 RFA certification is as follows:
For the 1,600 small water systems that would be affected, the average
annual cost for complying with this rule represents no more than 0.8%
of system revenues (the highest estimated percentage is for GW systems
serving 500 or fewer people, at 0.8% of its median revenue). Exhibit 7
presents the yearly cost to small systems and to EPA for the small
system sampling program, along with an illustration of system
participation for each year of UCMR 4.

                                                  Exhibit 7--Implementation of UCMR 4 at Small Systems
--------------------------------------------------------------------------------------------------------------------------------------------------------
           Cost description                2017              2018                      2019                      2020               2021      Total \1\
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                              Costs to EPA for Small System Program (Assessment Monitoring)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                               $0  $5,971,948..............  $5,971,948..............  $5,971,948..............         $0   $17,915,845
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                     Costs to Small Systems (Assessment Monitoring)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                0  $273,210................  $273,210................  $273,210................          0      $819,631
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                     Total Costs to EPA and Small Systems for UCMR 4
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                0  $6,245,159..............  $6,245,159..............  $6,245,159..............          0   $18,735,476
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         System Monitoring Activity Timeline \2\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Assessment Monitoring: Cyanotoxins....  .........  1/3 PWSs Sample.........  1/3 PWSs Sample.........  1/3 PWSs Sample.........  .........           800
Assessment Monitoring: 20 Additional    .........  1/3 PWSs Sample.........  1/3 PWSs Sample.........  1/3 PWSs Sample.........  .........           800
 Chemicals.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Totals may not equal the sum of components due to rounding.
\2\ Total number of systems is 1,600. No small system conducts Assessment Monitoring for both cyanotoxins and the 20 additional chemicals.

    PWS costs are attributed to the labor required for reading about
UCMR 4 requirements, monitoring, reporting and record keeping. The
estimated average annual burden across the 5-year UCMR 4 implementation
period of 2017-2021 is 2.8 hours at $103 per small system. Average
annual cost, in all cases, is less than 0.8% of system revenues. By
assuming all costs for laboratory analyses, shipping and quality
control for small entities, EPA incurs the entirety of the non-labor
costs associated with UCMR 4 small system monitoring, or 96% of total
small system testing costs. Exhibit 8 and Exhibit 9 present the
estimated economic impacts in the form of a revenue test for publicly-
and privately-owned systems.

                    Exhibit 8--UCMR 4 Relative Cost Analysis for Small Publicly-Owned Systems
                                                   [2017-2021]
----------------------------------------------------------------------------------------------------------------
                                                                     Average         Average
                                                 Annual  number   annual hours     annual cost     Revenue test
     System size (number of people served)         of  systems     per system      per system        \2\ (%)
                                                  impacted \1\     (2017-2021)     (2017-2021)
----------------------------------------------------------------------------------------------------------------
                                              Ground Water Systems
----------------------------------------------------------------------------------------------------------------
500 and under..................................               4             1.6             $59             0.16
501 to 3,300...................................              32             1.7              63             0.04
3,301 to 10,000................................              36             1.9              67             0.01
----------------------------------------------------------------------------------------------------------------
                                        Surface Water (and GWUDI) Systems
----------------------------------------------------------------------------------------------------------------
500 and under..................................               4             3.3             118             0.17
501 to 3,300...................................              48             3.3             118             0.04

3,301 to 10,000................................             109             3.4             123             0.01
----------------------------------------------------------------------------------------------------------------
\1\ PWS counts were adjusted to display as whole numbers in each size category.
\2\ The Revenue Test was used to evaluate the economic impact of an information collection on small government
  entities (e.g., publicly-owned systems); costs are presented as a percentage of median annual revenue in each
  size category.

                   Exhibit 9--UCMR 4 Relative Cost Analysis for Small Privately-Owned Systems
                                                   [2017-2021]
----------------------------------------------------------------------------------------------------------------
                                                                     Average         Average
                                                 Annual  number   annual hours     annual cost     Revenue test
     System size (number of people served)         of  systems     per system      per system        \2\ (%)
                                                  impacted \1\     (2017-2021)     (2017-2021)
----------------------------------------------------------------------------------------------------------------
                                              Ground Water Systems
----------------------------------------------------------------------------------------------------------------
500 and under..................................              13             1.6             $59             0.81
501 to 3,300...................................              12             1.7              63             0.05
3,301 to 10,000................................               8             1.9              67             0.01
----------------------------------------------------------------------------------------------------------------
                                        Surface Water (and GWUDI) Systems
----------------------------------------------------------------------------------------------------------------
500 and under..................................               4             3.3             118             0.29
501 to 3,300...................................              17             3.3             118             0.04
3,301 to 10,000................................              32             3.4             123             0.01
----------------------------------------------------------------------------------------------------------------
\1\ PWS counts were adjusted to display as whole numbers in each size category.
\2\ The Revenue Test was used to evaluate the economic impact of an information collection on small government
  entities (e.g., privately-owned systems); costs are presented as a percentage of median annual revenue in each
  size category.

    The Agency has determined that 1,600 small PWSs (for Assessment
Monitoring), or approximately 4.2% of all small systems, would
experience an impact of no more than 0.8% of revenues; the remainder of
small systems would not be impacted.
    Although this proposed rule will not have a significant economic
impact on a substantial number of small entities, EPA has attempted to
reduce this impact by assuming all costs for analyses of the samples
and for shipping the samples from small systems to laboratories
contracted by EPA to analyze UCMR 4 samples (the cost of shipping is
now included in the cost of each analytical method). EPA has set aside
$2.0 million each year from the Drinking Water State Revolving Fund
(SRF) with its authority to use SRF monies for the purposes of
implementing this provision of SDWA. Thus, the costs to these small
systems will be limited to the labor associated with collecting a
sample and preparing it for shipping.
    I certify that this action will not have a significant economic
impact on a substantial number of small entities under the RFA. In
making this determination, the impact of concern is any significant
adverse economic impact on small entities. Although EPA has concluded
that this action will have no significant net regulatory burden for
directly regulated small entities, the Agency continues to be
interested in the potential impacts of the proposed rule on small
entities and welcomes comments on issues related to such impacts.

D. Unfunded Mandates Reform Act (UMRA)

    This action does not contain an annual unfunded mandate of $100
million or more as described in UMRA, 2 U.S.C. 1531-1538, and does not
significantly or uniquely affect small governments.

E. Executive Order 13132: Federalism

    This action does not have federalism implications. It will not have
substantial direct effects on the states, on the relationship between
the national government and the states, or on the distribution of power
and responsibilities among the various levels of government.
    Consistent with EPA policy to promote communications between EPA
and state and local governments, EPA specifically solicits comment on
the proposed rule from state and local officials.

F. Executive Order 13175: Consultation and Coordination With Indian
Tribal Governments

    This action will neither impose substantial direct compliance costs
on federally recognized tribal governments, nor preempt tribal law. As
described previously, this proposed rule requires monitoring by all
large PWSs. Information in the SDWIS/Fed water system inventory
indicates there are approximately 17 large tribal PWSs (ranging in size
from 10,001 to 40,000 customers). EPA estimates the average annual cost
to each of these large PWSs, over the 5-year rule period, to be $4,037.
This cost is based on a labor component (associated with the collection
of samples), and a non-labor component (associated with shipping and
laboratory fees), and represents less than 1.2% of average revenue/
sales for large PWSs. UCMR also requires monitoring by a nationally
representative sample of small PWSs. EPA estimates that less than 2% of
small tribal systems will be selected as a nationally representative
sample for Assessment Monitoring. EPA estimates the average annual cost
to small tribal systems over the 5-year rule period to be $103. Such
cost is based on the labor associated with collecting a sample and
preparing it for shipping

and represents less than 0.8% of average revenue/sales for small PWSs.
All other small-PWS expenses (associated with shipping and laboratory
fees) are paid by EPA.
    EPA consulted with tribal officials under the EPA Policy on
Consultation and Coordination with Indian Tribes early in the process
of developing this proposed rule to permit them to have meaningful and
timely input into its development. A summary of that consultation is
provided in the electronic docket listed in the ADDRESSES section at
the beginning of this notice. EPA specifically solicits additional
comment on this proposed rule from tribal officials.

G. Executive Order 13045: Protection of Children From Environmental
Health Risks and Safety Risks

    This action is not subject to Executive Order 13045 because it is
not economically significant as defined in Executive Order 12866, and
because EPA does not think the environmental health or safety risks
addressed by this action present a disproportionate risk to children.
This action's health and risk assessments are addressed in section II.N
of the preamble.

H. Executive Order 13211: Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution or Use

    This action is not subject to Executive Order 13211, because it is
not a significant regulatory action under Executive Order 12866.

I. National Technology Transfer and Advancement Act and 1 CFR Part 51

    This action involves technical standards. EPA proposes to use
methods developed by the Agency, three major voluntary consensus method
organizations and the Ohio EPA to support UCMR 4 monitoring. The
voluntary consensus method organizations are Standard Methods,
Association of Analytical Communities International and ASTM
International. EPA identified acceptable consensus method organization
standards for the analysis of manganese and germanium. Additionally,
EPA identified an Ohio EPA method for the analysis of total
microcystins using ADDA by ELISA. EPA therefore proposes using a
collection of analytical methods published by these parties for the
UCMR 4 analytes. In addition, there are several consensus standards
that are approved for compliance monitoring that will be available for
use in the analysis of TOC and bromide, and for the measurement of
temperature and pH. A summary of each method along with how the method
specifically applies to UCMR 4 can be found in section II.J of the
preamble.
    All of these standards are reasonably available for public use. The
Agency methods are free for download on EPA's Web site. The methods in
the Standard Method 21st edition are consensus standards, available for
purchase from the publisher, and are commonly used by the drinking
water community. The methods in the Standard Method Online are
consensus standards, available for purchase from the publisher's Web
site, and are commonly used by the drinking water community. The
methods from ASTM International are consensus standards, are free for
download from the publisher's Web site, and are commonly used by the
drinking water community. The Ohio EPA method is free for download on
their Web site and is increasingly being used by the drinking water
community.
    EPA welcomes comments on this aspect of the proposed rulemaking;
the Agency specifically invites the public to identify potentially-
applicable voluntary consensus standards and explain why such standards
should be used in this rule.

J. Executive Order 12898: Federal Actions To Address Environmental
Justice in Minority Populations and Low-Income Populations

    The EPA believes the human health or environmental risk addressed
by this action will not have potential disproportionately high and
adverse human health or environmental effects on minority, low-income
or indigenous populations. The results of this evaluation are contained
in section II.O of this preamble and an additional supporting document
has been placed in the docket.

IV. References

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Programs' Resources and Needs. December 2013.
ASTM. 2010. ASTM D5673-10--Standard Test Method for Elements in
Water by Inductively Coupled Plasma-Mass Spectrometry. Approved
August 1, 2010. Available for purchase on the Internet at http://www.astm.org/Standards/D5673.htm.
ASTM. 2012a. ASTM D1293-12--Standard Test Methods for pH of Water.
Available for purchase on the Internet at http://www.astm.org/Standards/D1293.htm.
ASTM. 2012b. ASTM D6581-12--Standard Test Methods for Bromate,
Bromide, Chlorate, and Chlorite in Drinking Water by Suppressed Ion
Chromatography. Available for purchase on the Internet at http://www.astm.org/Standards/D6581.htm.
Fischer, W.J., Garthwaite, I., Miles, C.O., Ross, K.M., Aggen, J.B.,
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Graham, J.L., Loftin, K.A., Ziegler, A.C., and Meyer, M.T. 2008.
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McElhiney, J., and Lawton, L.A. 2005. Detection of the
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purchase on the Internet at http://www.standardmethods.org.
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Ion Chromatography Samples. Revision 2.1. Available on the Internet
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Waters and Wastes by Inductively Coupled Plasma-Mass Spectrometry.
Revision 5.4. Available on the Internet at https://www.nemi.gov/.
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Drinking Water by Ion Chromatography. Revision 1.0. 1997. Available
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Disinfection By-Products in Drinking Water Using Ion Chromatography
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Dalapon in Drinking Water by Liquid-Liquid Microextraction,
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