[Federal Register: January 4, 2007 (Volume 72, Number 2)]
[Rules and Regulations]
[Page 367-398]
[DOCID:fr04ja07-18]

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Part II

Environmental Protection Agency

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40 CFR Parts 9, 141, and 142

Unregulated Contaminant Monitoring Regulation (UCMR) for Public Water
Systems Revisions; Final Rule

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 9, 141 and 142

[Docket No. OW-2004-0001; FRL-8261-7]
RIN 2040-AD93

Unregulated Contaminant Monitoring Regulation (UCMR) for Public
Water Systems Revisions

AGENCY: Environmental Protection Agency.

ACTION: Final rule.

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SUMMARY: The Safe Drinking Water Act (SDWA), as amended in 1996,
requires the United States Environmental Protection Agency (EPA) to
establish criteria for a program to monitor unregulated contaminants
and to publish a list of contaminants to be monitored every five years.
EPA published the first set of contaminants in 1999. This final
regulation meets the SDWA requirement by publishing the next set of
unregulated contaminants to be monitored and the requirements for such
monitoring.
    This final rule describes the design for the second Unregulated
Contaminant Monitoring Regulation (UCMR) cycle (i.e., UCMR 2) of 2007-
2011. EPA is requiring monitoring of 25 chemicals using 5 different
analytical methods. UCMR 2 monitoring will occur during 2008-2010.
Implementation of this final rule will benefit the environment by
providing EPA and other interested parties with scientifically valid
data on the occurrence of these contaminants in drinking water, thereby
permitting the assessment of the population potentially being exposed
and the levels of that exposure. These data are the primary source of
occurrence and exposure data for the Agency to determine whether to
regulate these contaminants.

DATES: This final rule is effective on February 5, 2007. For purposes
of judicial review, this rule is promulgated as of 1 p.m. eastern time
on January 4, 2007 as provided in 40 CFR 23.7. The incorporation by
reference of certain publications listed in this rule is approved by
the Director of the Federal Register as of February 5, 2007.

ADDRESSES: EPA has established a docket for this action under Docket ID
No. OW-2004-0001. All documents in the docket are listed in the index
at http://www.regulations.gov. Although listed in the index, some information

is not publicly available, e.g., confidential business information or
other information whose disclosure is restricted by statute. Certain
other material, such as copyrighted material, is not placed on the
Internet and will be publicly available only in hard copy form.
Publicly available docket materials are available either electronically
at http://www.regulations.gov or in hard copy at the Water Docket, EPA/

DC, EPA West, Room 3334, 1301 Constitution Ave., NW., Washington, DC.
This Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday
through Friday, excluding legal holidays. The telephone number for this
Public Reading Room is<PHONE_NUMBER>, and the telephone number for the
Water Docket is<PHONE_NUMBER>.

FOR FURTHER INFORMATION CONTACT: David J. Munch, Technical Support
Center, Office of Ground Water and Drinking Water, United States
Environmental Protection Agency, Office of Water, 26 West Martin Luther
King Drive (MS 140), Cincinnati, OH 45268, telephone<PHONE_NUMBER>; e-
mail address<EMAIL_ADDRESS>For general information, contact the
Safe Drinking Water Hotline. Callers within the United States may reach
the Hotline at<PHONE_NUMBER>. The Hotline is open Monday through
Friday, excluding legal holidays, from 10 a.m. to 4 p.m., eastern time.

SUPPLEMENTARY INFORMATION:

I. General Information

Does This Action Apply to Me?

    Entities regulated by this action are public water systems (PWSs).
All large community and non-transient non-community water systems
serving more than 10,000 people will be required to monitor. A
community water system means a PWS which serves at least 15 service
connections used by year-round residents or regularly serves at least
25 year-round residents. Non-transient non-community water system means
a PWS that is not a community water system and that regularly serves at
least 25 of the same people over 6 months per year. Only a nationally
representative sample of community and non-transient non-community
systems serving 10,000 or fewer people will be required to monitor.
Transient non-community systems (i.e., systems that do not regularly
serve at least 25 of the same people over 6 months per year) will not
be required to monitor. States, Territories, and Tribes that qualify
for treatment as a State for purposes of this program, may participate
in the implementation of the second cycle of the Unregulated
Contaminant Monitoring Regulation (i.e., UCMR 2) through a Partnership
Agreement. These agencies may choose to conduct analyses to measure for
contaminants in water samples collected for the UCMR 2, in which case
they will be regulated by this action.
    Regulated categories and entities are identified in the following
table.

------------------------------------------------------------------------
                                    Examples of potentially
             Category                 regulated entities       NAICS\a\
------------------------------------------------------------------------
State, local, & tribal             States, local and tribal       924110
 Governments.                       governments that
                                    analyze water samples
                                    on behalf of PWSs
                                    required to conduct
                                    such analysis; States,
                                    local and tribal
                                    governments that
                                    directly operate
                                    community and non-
                                    transient non-community
                                    water systems required
                                    to monitor.
Industry.........................  Private operators of           221310
                                    community and non-
                                    transient non-community
                                    water systems required
                                    to monitor.
Municipalities...................  Municipal operators of        924110
                                    community and non-
                                    transient non-community
                                    water systems required
                                    to monitor.
------------------------------------------------------------------------
\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 lists the types of entities that EPA is now aware
could potentially be regulated by this action. Other types of entities
not listed in the table could also be regulated. To determine whether
your facility is regulated by this action, you should carefully examine
the definition of PWS in Sec.  141.2 of title 40 of the Code of Federal
Regulations, and applicability criteria in Sec.  141.40(a)(1) and (2)
of this final action. If you have questions regarding the applicability
of this action to a particular entity, consult the person

listed in the preceding FOR FURTHER INFORMATION CONTACT section.

Abbreviations and Acronyms

HBB 2,2',4,4',5,5'-hexabromobiphenyl
[mu]g/L Microgram per liter
ASDWA Association of State Drinking Water Administrators
BDE-47 2,2',4,4'-tetrabromodiphenyl ether
BDE-99 2,2',4,4',5-pentabromodiphenyl ether
BDE-100 2,2',4,4',6-pentabromodiphenyl ether
BDE-153 2,2',4,4',5,5'-hexabromodiphenyl ether
CCL Contaminant Candidate List
CFR Code of Federal Regulations
DBP Disinfection Byproduct
DBPR Stage 1 or Stage 2 Disinfectants and Disinfection Byproducts Rule
DSMRT Distribution system maximum residence time
DQO Data quality objective
DWSRF Drinking Water State Revolving Fund
EPA United States Environmental Protection Agency
EPTDS Entry point to the distribution system
ESA Ethane sulfonic acid
FR Federal Register
GC Gas chromatography
GWUDI Ground water under the direct influence of surface water
HAA5 Haloacetic acid 5 (5 HAAs currently regulated)
HPLC High performance liquid chromatography
HRPIR Half range prediction interval of results
ICR Information collection request
IDC Initial demonstration of capability
IDSE Initial distribution system evaluation
IHS Indian Health Service
LC Liquid chromatography
LCMRL Lowest concentration minimum reporting level
LFSM Laboratory fortified sample matrix
LFSMD Laboratory fortified sample matrix duplicate
MCL Maximum contaminant level
MRL Minimum reporting level
MS Mass spectrometry
NAICS National American Industry Classification System
NCOD National Drinking Water Contaminant Occurrence Database
NDBA N-nitroso-di-n-butylamine
NDEA N-nitrosodiethylamine
NDMA N-nitrosodimethylamine
NDPA N-nitroso-di-n-propylamine
NMEA N-nitrosomethylethylamine
NPDWR National Primary Drinking Water Regulation
NPYR N-nitrosopyrrolidine
NTTAA National Technology Transfer and Advancement Act
OA Oxanilic acid
OMB Office of Management and Budget
PA Partnership agreement
PIR Prediction interval of results
PT Proficiency testing
PWS Public water system
PWSID Public water system identification
QA Quality assurance
QC Quality control
RDX Hexahydro-1,3,5-trinitro-1,3,5-triazine
RFA Regulatory Flexibility Act
RSD Relative standard deviation
SBA Small Business Administration
SDWA Safe Drinking Water Act
SDWARS Safe Drinking Water Accession and Review System
SDWIS Safe Drinking Water Information System
SPE Solid phase extraction
TNT 2,4,6-trinitrotoluene
TTHM Total trihalomethanes
UCMR Unregulated Contaminant Monitoring Regulation
UMRA Unfunded Mandates Reform Act of 1995
USEPA United States Environmental Protection Agency

Table of Contents

I. General Information
    Does This Action Apply to Me?
II. Statutory Authority and Background
    A. What Is the Statutory Authority for UCMR?
    B. How Does EPA Meet These Statutory Requirements?
III. Summary of This Rule
    A. What Are the Major Changes between the Proposed and Final
Rule?
    Exhibit 1: Changes to UCMR 2 between Proposed and Final Rule
    B. Which Water Systems Must Monitor?
    1. This Rule
    2. Summary of Major Comments
    C. What Are the UCMR 2 Priority Contaminants and Associated
Methods?
    1. List Compilation
    Exhibit 2: Analytical Methods Approved for UCMR 2 Monitoring
    2. Acetanilide Pesticides, Degradation Products, and Related
Methods
    3. Explosives and Related Methods
    4. Perchlorate and Related Methods
    5. Nitrosamines/NDMA and Related Methods
    6. Flame Retardants, Other Priority Contaminants, and Related
Methods
    7. Triazines Chlorodegradates and Parent Compounds
    8. Other Compounds That Were Considered
    D. How Are Laboratories Approved for UCMR 2 Monitoring?
    1. This Rule
    2. Summary of Major Comments
    E. What Is A System's Responsibility Regarding the Use of
Laboratories?
    1. This Rule
    2. Summary of Major Comments
    F. What Specific Quality Control Requirements Must Be Followed?
    1. Method Development Approach and Method Defined Quality
Control
    2. Minimum Reporting Level
    3. Lowest Concentration Minimum Reporting Level
    4. Laboratory Fortified Sample Matrix and Laboratory Fortified
Sample Matrix Duplicate
    G. When Are Samples Collected?
    1. This Rule
    2. Summary of Major Comments
    H. Where Are Samples Collected?
    1. Entry Points to the Distribution System
    2. Distribution System Maximum Residence Time
I. How Should Samples Be Collected?
    1. This Rule
    2. Summary of Major Comments
    J. What Are the UCMR 2 Reporting Requirements?
    1. Information Required Prior to Monitoring
    2. Reporting of Required Data Elements
    3. Reporting Process
    4. Cross-Media Reporting and Data Availability
    K. What Constitutes a Violation Under UCMR 2?
    L. Technical Correction Rule Changes in This Rule
    1. Changes Pertaining to Aldicarb Monitoring
    2. Changes Pertaining to State Primacy
IV. State and Tribal Participation
    A. Partnership Agreements
    1. This Rule
    2. Summary of Major Comments
    B. Governors' Petition and State-Wide Waivers
V. Cost and Benefits of This Rule
VI. Statutory and Executive Order Reviews
    A. Executive Order 12866: Regulatory Planning and Review
    B. Paperwork Reduction Act
    C. Regulatory Flexibility Act
    D. Unfunded Mandates Reform Act
    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 and Safety Risks
    H. Executive Order 13211: Actions That Significantly Affect
Energy Supply, Distribution, or Use
    I. National Technology Transfer and Advancement Act
    J. Executive Order 12898: Federal Actions To Address
Environmental Justice in Minority Populations and Low-Income
Populations
    K. Congressional Review Act
VII. Public Involvement in Regulation Development
VIII. References

List of Exhibits

Exhibit 1: Changes to UCMR 2 between Proposed and Final Rule
Exhibit 2: Analytical Methods Approved for UCMR 2 Monitoring

II. Statutory Authority and Background

A. What Is the Statutory Authority for UCMR?

    Section 1445(a)(2) of the Safe Drinking Water Act (SDWA), as
amended in 1996, requires that once every five years, beginning in
August 1999, the United States Environmental Protection Agency (EPA)
shall issue a list of no more than 30 unregulated contaminants to be
monitored by public water systems (PWSs), and that EPA enter the
monitoring data into the National Drinking Water Contaminant Occurrence
Database (NCOD). EPA's UCMR program must ensure that only a nationally
representative sample of PWSs serving 10,000 or fewer people will be
required to monitor; however, there are no such restrictions on the
number of systems serving more than 10,000 people. EPA must vary the
frequency and schedule for monitoring based on the number of people a
system serves, the source of supply, and the contaminants likely to be
found.

B. How Does EPA Meet These Statutory Requirements?

    To fulfill the initial SDWA requirements, EPA published ``Revisions
to the Unregulated Contaminant Monitoring Regulation for Public Water
Systems; Final Rule,'' on September 17, 1999 (64 FR 50556, (USEPA,
1999)). Several supplemental rules were published to establish
analytical methods and to provide clarifications and refinements to the
initial rule: 65 FR 11372, March 2, 2000 (USEPA, 2000); 66 FR 2273,
January 11, 2001 (USEPA, 2001a); and 67 FR 65888, October 29, 2002
(USEPA, 2002b). SDWA, as amended in 1996, requires that at least once
every five years EPA identify a list of no more than 30 unregulated
contaminants to be monitored. This final action fulfills this statutory
obligation, identifying 25 priority contaminants for monitoring using
five analytical methods. EPA has developed a contaminant list (Exhibit
2, in Section III.C.1) and sampling design for UCMR 2 (2007-2011) with
input from both stakeholders and an EPA working group. This list is the
same as was presented in the proposed rule, with one exception:
perchlorate has been removed from the UCMR 2 monitoring requirements
(see Section III.C. 4 for further discussion).

III. Summary of This Rule

A. What Are the Major Changes Between the Proposed and Final Rule?

    EPA published ``Revisions to the Unregulated Contaminant Monitoring
Regulation for Public Water Systems; Proposed Rule,'' on August 22,
2005 (70 FR 49094, (USEPA, 2005a)). EPA received comments from 36
public commenters.
    In response to comments received and further consideration, EPA
removed perchlorate from the list of contaminants to be monitored for
under UCMR 2, and revised or clarified requirements pertaining to
system applicability criteria, reporting, monitoring, and quality
control. In addition, to accommodate PWS preparation for rule
implementation and to provide additional assurance of sufficient
laboratory capacity, this rule contains revised language that changes
the start of monitoring from July 2007 to January 2008, such that the
effective monitoring period is now January 2008 through December 2010.
Exhibit 1 provides a summary of these changes, and a listing of the
corresponding preamble section, which provides a more detailed
discussion of the revisions and related public comments. Sections
III.B-K summarize the different aspects of this rule and the associated
major comments received in response to the August 2005 proposed rule
and their impact, if any, on this rule.
    This summary focuses on the changes between the proposed and final
rule, and requirements with deadlines that are triggered by the
publication date of this final rule. EPA has compiled a document
containing all public comments and EPA's responses entitled ``UCMR 2
Categorized Public Comments,'' which can be obtained by going to http://www.regulations.gov
, and searching for Docket ID No. OW-2004-0001

under the advanced search tab.

                          Exhibit 1.--Changes to UCMR 2 between Proposed and Final Rule
----------------------------------------------------------------------------------------------------------------
                         Rule section
---------------------------------------------------------------  Description of change    Corresponding preamble
                Number                    Title/description                                      section
----------------------------------------------------------------------------------------------------------------
141.35(a)............................  General applicability..  Defines ``finished       III.B.
                                                                 water'' to clarify the
                                                                 definition of
                                                                 ``population served''.
141.35(c)(3)(i)......................  Documenting ground       Clarifies that approved  III.J.1.c.
                                        water representative     representative well
                                        sampling locations.      plans from previous
                                                                 UCMR cycles can be
                                                                 submitted to identify
                                                                 representative entry
                                                                 point(s).
141.35(c)(5).........................  PWS notification of EPA  Provides exception to    III.J.1.d.
                                        if sampling schedule     notification
                                        cannot be met.           requirement for PWS
                                                                 with ground water
                                                                 sampling location that
                                                                 can collect second
                                                                 sample sets within 5-7
                                                                 months of the first
                                                                 sample set.
141.35(e)............................  Data Elements..........  Revises Table 1 of Sec.  III.J.2.
                                                                   141.35 to:
                                                                1. Clarify the
                                                                 definition of ``Water
                                                                 Source Type'' for a
                                                                 sampling point..
                                                                2. Change the name of
                                                                 ``Sampling Point Type
                                                                 Identification Code''
                                                                 to ``Sampling Point
                                                                 Type Code'' and
                                                                 distinguish this data
                                                                 element from
                                                                 ``Sampling Point
                                                                 Identification Code''..
                                                                3. Clarify the
                                                                 definition for
                                                                 ``Disinfectant
                                                                 Residual Type''..
141.40(a)(3).........................  Analytes to be           Revises Table 1 of       III.G.
                                        monitored and            141.40 to:              III.C.4.
                                        monitoring period.      1. Change monitoring     III.F.2.
                                                                 begin date to January
                                                                 2008, and Screening
                                                                 Survey monitoring
                                                                 period to coincide
                                                                 with Assessment
                                                                 Monitoring..
                                                                2. Delete perchlorate
                                                                 from table and
                                                                 associated footnotes..
                                                                3. Revise minimum
                                                                 reporting levels to
                                                                 one significant
                                                                 figure..

141.40(a)(4)(i)(A)...................  Monitoring schedules...  Clarifies that EPA or    III.G. and III.J.1.d.
                                                                 the State will
                                                                 determine PWS
                                                                 monitoring schedules.
141.40(a)(4)(i)(B)...................  Frequency..............  1. Requires PWSs with    III.G.
                                                                 ground water sampling
                                                                 locations that cannot
                                                                 collect their second
                                                                 samples within 5-7
                                                                 months of the first
                                                                 samples to contact EPA.
                                                                2. Changes Table 2 to
                                                                 indicate that ground
                                                                 water sample events
                                                                 must occur 5-7 months
                                                                 apart..
141.40(a)(4)(i)(D)...................  Sampling Instructions..  1. Clarifies that        III.C.2; III.F.1; and
                                                                 acetanilide parent and   III.C.4.
                                                                 degradates must be
                                                                 sampled at the same
                                                                 time and location.
                                                                2. Deletes reference to
                                                                 collection methods for
                                                                 perchlorate samples.
141.40(a)(4)(i)(G)...................  Laboratory errors or     Changes resampling       III. I.
                                        sampling deviations.     deadline from within
                                                                 14 days to within 30
                                                                 days.
141.40(a)(5)(i)......................  Sample collection        Deletes reference to     III.C.4.
                                        preservation.            preservation methods
                                                                 for perchlorate
                                                                 samples.
141.40(a)(5)(iii)(B)(2)..............  Quality control          Deletes additional       III.C.4.
                                        requirements.            quality control
                                                                 requirements for
                                                                 perchlorate methods.
141.40(a)(5)(iv).....................  Laboratory accuracy and  Changes method           III.F.4.
                                        precision.               requirement to fortify
                                                                 the matrix at the
                                                                 minimum reporting
                                                                 level (MRL)
                                                                 concentration to
                                                                 within ;+/-50% vs. +/-
                                                                 20%.
141.40(a)(5)(v)......................  Detection confirmation   Deletes requirements in  III.C.4 and III.F.1.
                                        for perchlorate.         this section; and
                                                                 renumbers subsequent
                                                                 paragraphs accordingly.
----------------------------------------------------------------------------------------------------------------

B. Which Water Systems Must Monitor?

1. This Rule
    This rule requires that Assessment Monitoring be conducted by all
large community and non-transient, non-community water systems serving
more than 10,000 people, and a nationally representative sample of 800
small water systems serving 10,000 or fewer people. Transient non-
community water systems and those systems that purchase all of their
finished water from another system are excluded from the requirements
of UCMR 2. Assessment Monitoring is the largest in scope of the three
UCMR 2 monitoring components (or tiers). Under Assessment Monitoring,
``List 1'' contaminants, for which standard analytical methods are
available, are monitored to assess national occurrence in drinking
water. These are the priority contaminants for which analytical method
technologies are well established.
    The second tier of UCMR 2 is referred to as ``List 2'' or Screening
Survey monitoring. List 2 contaminants are those for which analytical
methods have been recently developed, and for which the technologies
are not widely used; laboratory capacity, therefore, may be
insufficient to conduct the larger scale Assessment Monitoring. The
Screening Survey will be conducted by approximately 400 PWSs serving
more than 100,000 people (all systems in this largest size category),
by a randomly selected sample of 320 PWSs serving between 10,001 and
100,000 people, and by 480 small PWSs.
    Pre-Screen Testing, the third tier of UCMR monitoring that is
designed for priority ``List 3'' contaminants, whose methods are very
new or specialized, is not required in this action, although EPA is
retaining the regulatory language that supports Pre-Screen Testing
authority as part of the three-tiered UCMR framework. If EPA ultimately
decides to include Pre-Screen Testing as part of this or a future UCMR,
EPA will initiate a rulemaking action to propose List 3 contaminants
(and their associated analytical methods) and to solicit public
comments.
    This rule also defines ``population served'' as ``the number of
people served directly by the PWS'' plus those served ``by any
consecutive system receiving all or part of its finished water from
that PWS.'' To help clarify the definition of population served, the
final regulation will also include the definition of ``finished water''
that was recently finalized as part of the ``Stage 2 Disinfectants and
Disinfection Byproducts Rule'' (71 FR 388, January 4, 2006 (USEPA,
2006a)) as follows: ``Finished water is water that is introduced into
the distribution system of a public water system and is intended for
distribution and consumption without further treatment, except the
treatment necessary to maintain water quality in the distribution
system (e.g., booster disinfection, addition of corrosion control
chemicals).'' This final regulation also specifies the PWS system's
water source and population served, as of June 30, 2005, as the basis
for establishing a defined list of PWSs that are subject to the rule
requirements.
2. Summary of Major Comments
    Comments included a recommendation for EPA to define the term
``finished water'' in EPA's definition of ``population served,'' and
support for the designation of the June 30, 2005, applicability date
because it would eliminate some of the confusion that occurred under
UCMR 1 and avoid extra effort to keep monitoring plans accurate and
current. In response to these comments, this final regulation contains
the definition of ``finished water'' that was recently finalized as
part of the Stage 2 Disinfection Byproducts Rule and retains the
proposed applicability date. EPA agrees that the specific applicability
date of June 30, 2005, will help to streamline the implementation
process.
    Other comments included recommendations to publish the list of
systems that are subject to UCMR 2. Such a list, including preliminary
schedules, is posted on the UCMR Web page: http://www.epa.gov/safewater/ucmr/ucmr2
.

C. What Are the UCMR 2 Priority Contaminants and Associated Methods?

1. List Compilation
a. This Rule
    This rule specifies 25 contaminants for monitoring, along with five
EPA

Methods for analysis as listed in Exhibit 2. EPA began with a list of
over 200 contaminants, compiled from a variety of different sources,
including: UCMR 1 reserved contaminants; Candidate Contaminant List 1
(CCL 1) ``deferred pesticides''; CCL 1 suspected endocrine disruptors;
and other emerging contaminants. The CCL is a list of contaminants that
are not subject to any proposed or promulgated National Primary
Drinking Water Regulation (NPDWR), are known or anticipated to occur at
PWSs, and may require regulation under SDWA. The first CCL, published
in March 1998 (referred to as ``CCL 1''), identified 60 contaminants or
contaminant groups (63 FR 10274, March 2, 1998 (USEPA, 1998b)) that
were divided into categories to represent research and data needs for
each of the following: (1) Regulatory determination priorities; (2)
health effects research priorities; (3) treatment research priorities;
(4) analytical methods research priorities; and (5) occurrence
priorities. Through a multi-stepped review and prioritization process
(with relative health effects the top priority), the UCMR analyte list
was narrowed and prioritized, as described in the August 2005 proposed
rule, and 26 contaminants were identified. However, based on public
comment and further consideration, EPA has removed the requirement for
monitoring perchlorate under the UCMR 2 program (see Section III.C.4).

      Exhibit 2.--Analytical Methods Approved for UCMR 2 Monitoring
------------------------------------------------------------------------
     Analytical method \1\            Contaminant        UCMR 2 ``List''
------------------------------------------------------------------------
EPA Method 527 (SPE/GC/MS)....  2,2',4,4'-              List 1,
                                 tetrabromodiphenyl      Assessment
                                 ether (BDE-47).         Monitoring: 7
                                                         contaminants.
                                2,2',4,4',5-
                                 pentabromodiphenyl
                                 ether (BDE-99).
                                2,2',4,4',5,5'-
                                 hexabromobiphenyl
                                 (HBB).
                                2,2',4,4',5,5'-
                                 hexabromodiphenyl
                                 ether (BDE-153).
                                2,2',4,4',6-
                                 pentabromodiphenyl
                                 ether (BDE-100).
                                Dimethoate............
                                Terbufos sulfone......
EPA Method 529 (SPE/GC/MS)....  1,3-dinitrobenzene....  List 1,
                                                         Assessment
                                                         Monitoring: 3
                                                         contaminants.
                                2,4,6-trinitrotoluene
                                 (TNT).
                                Hexahydro-1,3,5-
                                 trinitro-1,3,5-
                                 triazine (RDX).
EPA Method 521 (SPE/GC/CI/MS/   N-nitrosodiethylamine   List 2,
 MS).                            (NDEA).                 Screening
                                                         Survey: 6
                                                         contaminants.
                                N-nitrosodimethylamine
                                 (NDMA).
                                N-nitroso-di-n-
                                 butylamine (NDBA).
                                N-nitroso-di-n-
                                 propylamine (NDPA).
                                N-
                                 nitrosomethylethylami
                                 ne (NMEA).
                                N-nitrosopyrrolidine
                                 (NPYR).
EPA Method 535 (SPE/LC/MS/MS).  Acetochlor ethane       List 2,
                                 sulfonic acid (ESA).    Screening
                                                         Survey: 6
                                                         contaminants.
                                Acetochlor oxanilic
                                 acid (OA).
                                Alachlor ESA..........
                                Alachlor OA...........
                                Metolachlor ESA.......
                                Metolachlor OA........
EPA Method 525.2 (SPE/GC/MS)..  Acetochlor............  List 2,
                                                         Screening
                                                         Survey: 3
                                                         contaminants.
                                Alachlor..............
                                Metolachlor...........
Total of 25 UCMR 2
 contaminants .
------------------------------------------------------------------------
\1\ EPA Method 521: Determination of Nitrosamines in Drinking Water by
  Solid Phase Extraction and Capillary Column Gas Chromatography with
  Large Volume Injection and Chemical Ionization Tandem Mass
  Spectrometry (MS/MS) (USEPA, 2004a).
EPA Method 525.2: Determination of Organic Compounds in Drinking Water
  by Liquid-Solid Extraction and Capillary Column Gas Chromatography/
  Mass Spectrometry (USEPA, 1995).
EPA Method 527: Determination of Selected Pesticides and Flame
  Retardants in Drinking Water by Solid Phase Extraction and Capillary
  Column Gas Chromatography/Mass Spectrometry (GC/MS) (USEPA, 2004b).
EPA Method 529: Determination of Explosives and Related Compounds in
  Drinking Water by Solid Phase Extraction and Capillary Column Gas
  Chromatography/Mass Spectrometry (GC/MS) (USEPA, 2002a).
EPA Method 535, Revision 1.1: Measurement of Chloroacetanilide and Other
  Acetamide Herbicide Degradates in Drinking Water by Solid Phase
  Extraction and Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/
  MS) (USEPA, 2004c).

b. Summary of Major Comments
    Some commenters supported the contaminant selection process in
general, but disagreed with EPA's criterion that pesticides must be
currently registered to be considered for UCMR 2 because pesticides can
persist even after they are no longer in use. EPA agrees that the issue
of pesticides and their degradates is an important one and will
consider, in future contaminant selection processes, the commenters'
concern about the requirement that pesticides be registered. EPA did
not receive comments on its health effects prioritization process.
    Comments were received recommending that EPA substantially increase
the number of UCMR 2 contaminants because of the large number of
contaminants that are manufactured and sold in the United States.
Section 1445(a)(2)(B)(i) of SDWA specifically limits the number of
unregulated contaminants to 30 in each UCMR five-year cycle. The UCMR 2
list represents what EPA believes to be the highest priority drinking
water contaminants for which monitoring information is needed and
obtainable.
    Further comments indicated that EPA needs to clarify the process
for prioritization of both UCMR and CCL contaminants. In general,
concern was expressed that EPA did not sufficiently explain the status
of CCL research

priorities, especially with respect to the UCMR contaminant selection
process.
    In the August 2005 preamble to the proposed rule, as well as in
other past Federal Register notifications, EPA has explained in detail
the connections between the CCL and the UCMR programs (http://www.epa.gov/safewater/ucmr
). The preamble to the proposed UCMR 2

regulation presented the logic behind the consideration of potential
analytes for the UCMR. Section III ``Requirements of the Unregulated
Contaminant Monitoring Program'' detailed all aspects of how EPA
selected the contaminants proposed in this regulation with subsections
describing what priority contaminants were selected for UCMR 2; a
compilation of the initial list of potential UCMR 2 candidates; how EPA
established priorities for UCMR 2; EPA's health effects prioritization
approach; and the specific information and considerations that went
into EPA's decisions on each analyte selected.
    EPA has also been engaged in a multi-year process designed to
create an improved CCL process. This process began after the first CCL
was published in 1998 and EPA expects the next CCL (CCL 3) to reflect
substantial progress in implementing this new process. Because the new
CCL process was underway but not yet completed in 2005, CCL 2 carried
over the previous list and did not reflect the changes EPA is expecting
to make in identifying contaminants for possible regulation. EPA
expects that CCL 3 will reflect a more robust, transparent, and
systematic process to identify priority contaminants in drinking water
that will form the primary basis for future UCMR lists.
    Before EPA can list a chemical compound or microbiological
parameter on UCMR, adequate analytical methods must be available. For
some of the chemicals (i.e., organotins, triazines and algal toxins)
and for all the microbiological parameters listed on the CCL, adequate
analytical methods have not yet been developed. EPA is actively engaged
in analytical method development research for these parameters both in-
house and through its various contracts and grant mechanisms. EPA
regularly publishes journal articles and other reports on the progress
of all of these research activities that are available for the public
to review.
2. Acetanilide Pesticides, Degradation Products, and Related Methods
a. This Rule
    Under this rule, the three highest-use parent acetanilide
compounds, acetochlor, alachlor, and metolachlor, and their ESA and OA
degradation products are specified as List 2, Screening Survey
contaminants. The final rule also specifies EPA Method 525.2 for
analysis of the parent compounds and EPA Method 535 for analysis of the
acetanilide degradates. There were no changes between the proposed and
final rule language regarding these priority contaminants and their
associated methods. However, this rule contains revised language to
clarify that acetanilide parent and degradation product sampling must
be conducted at the same time and same location.
b. Summary of Major Comments
    Some commenters did not agree with EPA's proposal to monitor the
three parent acetanilide compounds because some water systems include
these as part of their regulated volatile organic compound analyses
using EPA Method 525.2. Another recommendation was that no special
certification for Method 525.2 be required, since many laboratories are
already approved to conduct this analysis for regulated contaminants.
EPA is requiring monitoring of these three parent pesticides because it
is essential that the acetanilide parent and the degradation products
analysis be conducted using samples collected in the same location and
at the same time to provide data on their relative concentrations
(i.e., to establish relationships, if any, between the two). In
addition, because UCMR requires only a sample of PWSs to conduct
monitoring, and the resulting occurrence data is used to support EPA
decisions about whether to regulate a contaminant to protect public
health, the quality of data collected, at minimum reporting levels that
are considerably lower than those used for compliance monitoring, is
very important. Therefore, the analyses must meet even more stringent
quality control procedures than those used for other national drinking
water analyses, and special approval of laboratories is warranted for
both EPA Method 535 and 525.2. These analyses are required as part of
the Screening Survey, and therefore analytical costs to PWSs are
limited to approximately 720 large systems (EPA is paying for the
analytical costs of small system monitoring).
    EPA agreed with recommendations in public comment to require
monitoring for acetanilide parents and their degradation products at
the same location and time to provide data on their relative
concentrations. The final regulation contains revised language to
include this requirement.
    Finally, concern was expressed in public comments that EPA may
develop a single maximum contaminant level (MCL) for the parents plus
their degradates; commenters specifically pointed out that different
toxicity endpoints may exist for parents and degradates, and that a
single MCL could conflict with some state standards. EPA has made no
decision regarding whether or how to regulate these compounds. Such
decisions are beyond the scope of this rule.
3. Explosives and Related Methods
a. This Rule
    Under this rule, EPA is requiring that three explosives: Hexahydro-
1,3,5-trinitro-1,3,5-triazine (RDX), 1,3-dinitrobenzene, and, 2,4,6-
trinitrotoluene (TNT) be monitored as part of List 1, Assessment
Monitoring. The final rule also specifies EPA Method 529 for analysis
of these compounds. There were no changes between the proposed and
final rule language regarding these priority contaminants and their
associated method.
b. Summary of Major Comments
    Some commenters thought that other contaminants may be more
widespread and should take priority over explosives for testing.
However, if monitoring for explosives was required, the commenters
recommended that it be limited to areas near munitions facilities. The
explosives have not yet undergone a sufficiently widespread occurrence
study for EPA to be confident that these contaminants are only a
concern near munitions facilities. The decision to monitor for these
contaminants, versus others considered, was driven by their potential
health effects through the process described previously.
4. Perchlorate and Related Methods
a. This Rule
    Under this rule, EPA has removed the requirement for monitoring
perchlorate under the UCMR 2 program. All references to perchlorate,
its associated methods, and specific quality control requirements have
been removed from the final rule. As a result, the requirements of
Sec.  141.40(a)(5)(v), Detection Confirmation, were deleted, and all
subsequent sections have been renumbered accordingly. The other rule
sections that were impacted by this decision (with reference to
perchlorate or relevant analytical methods being removed) are: Sec.
141.40(a)(3)--Analytes

to be monitored; Sec.  141.40(a)(4)(i)(D)--Sampling Instructions; Sec.
141.40(a)(5)(i)--Sample collection/preservation; and Sec.
141.40(a)(5)(iii)(B)(2)--Quality control requirements for validation of
laboratory performance at or below the MRL.
b. Summary of Major Comments
    Approximately 75 percent of commenters submitted comments on the
topic of perchlorate. The majority of the commenters did not support an
additional round of perchlorate monitoring, the most common reason
being the added cost of monitoring, without the perceived potential for
gaining sufficient, new information.
    Monitoring for perchlorate was conducted during UCMR 1 in over
3,800 PWSs, with a minimum reporting level of 4.0 micrograms per liter
([mu]g/L). The data collected during this survey represents a
statistically valid set of high quality data that will inform EPA on
the occurrence and potential exposure to perchlorate from public
drinking water supplies. EPA will continue to evaluate these exposure
data along with other available information (e.g., health effects) as
the Agency makes its regulatory determination. Until that evaluation is
complete, EPA agrees with the commenters that it is not clear that the
Agency needs additional information on the occurrence of perchlorate in
drinking water. As a result, imposing additional perchlorate monitoring
costs on water systems is not warranted at this time. Therefore, EPA
has removed the requirement for monitoring perchlorate under the UCMR 2
program. If EPA later decides that additional perchlorate monitoring is
warranted, the Agency will undertake an appropriate rulemaking action.
5. Nitrosamines/NDMA and Related Methods
a. This Rule
    This rule requires systems to monitor for six nitrosamines as part
of the List 2, Screening Survey. The final rule also specifies EPA
Method 521 for analysis of these compounds. There were no changes
between the proposed and final rule language regarding these priority
contaminants and their associated method.
b. Summary of Major Comments
    Some commenters thought that nitrosamine sampling would be more
appropriately conducted as part of the Stage 1 and Stage 2 DBPRs. EPA
disagrees with these comments for several reasons. While in fact, to
date, the scientific literature identifies only N-nitroso-dimethylamine
(NDMA) and N-nitrosodiethylamine (NDEA) as disinfection byproducts, the
Screening Survey for nitrosamines is designed to aid in understanding
the proportion of nitrosamines, particularly NDMA, that results from
source water contamination versus that which results from disinfection.
Also, the nitrosamines in this regulation are all compounds projected
to have significant adverse health effects. All of these compounds are
probable human carcinogens with 10-\6\ cancer risk levels
that are in the low nanogram per liter range. These compounds would be
high priorities for monitoring whether their occurrence is the result
of source water contamination or disinfection.
    Several commenters disagreed with the use of Method 521, mostly
because of questions on the scope and extent of interlaboratory testing
and validation. Commenters thought that methods that are already being
used by laboratories should be allowed under UCMR. Several commenters
gave specific suggestions as to which methods were commonly in use that
could be used for UCMR monitoring.
    The methods developed by EPA, for this and other chemical methods
needs for the analysis of drinking water, were subjected to a rigorous
process that included a series of testing, validation studies and peer
review, which went beyond the proficiency testing or round robin study
of the alternative draft unpublished methods suggested by the
commenters. Each individual procedure of every method proposed by EPA
was subjected to rigorous testing for a minimum of two years using
scientifically sound procedures. EPA's review of the suggested
alternative draft methods also identified technical deficiencies that
preclude their approval for monitoring under UCMR 2.
6. Flame Retardants, Other Priority Contaminants, and Related Methods
a. This Rule
    Under this rule, EPA is requiring monitoring for five flame
retardants, as well as terbufos sulfone and dimethoate, as part of List
1, Assessment Monitoring. The final rule also specifies EPA Method 527
for analysis of these compounds. There were no changes between the
proposed and final rule language regarding these priority contaminants
and their associated method.
b. Summary of Major Comments
    Concern was raised through public comment that only one citation
was provided in the proposed rule preamble supporting the rationale for
choosing this group of contaminants. Public comment suggestions were
made that there may be other groups of contaminants, such as endocrine
disruptors, that would be a better choice than the flame retardants.
EPA notes that both Darnerud, 2001 and Hites, 2004 were cited in the
preamble of the proposed regulation as sources of the statements
concerning flame retardants. There are however, many additional
articles in the scientific literature which could have also been cited.
In an article entitled ``An overview of brominated flame retardants in
the environment'' by Cynthia A. deWit, which was published in
Chemosphere, 46 (2002), the author cites over 180 published articles on
flame retardants. In addition, three published articles; T.E. Stoker,
``Toxicology and Applied Pharmacology'', 207 (2005); T.A. McDonald,
``Chemosphere'', 46 (2002); and I.A.T.M. Meerts, ``Environmental Health
Perspectives'', 109 Vol. 4 (2001) concern tests that have been
performed which support that the flame retardants specified for
monitoring in UCMR 2 are endocrine disruptors.
7. Triazines Chlorodegradates and Parent Compounds
a. This Rule
    In the proposed rule preamble, EPA solicited public comment
regarding three triazine chlorodegradates and three of their parent
compounds because the Agency is conducting a cumulative risk assessment
for the chlorodegradates as a group with atrazine, simazine, and
propazine. While atrazine and simazine are already regulated under
NPDWRs, EPA was considering UCMR monitoring for these parent compounds
concurrent with the collection of UCMR data for their degradation
products to determine the degree of correlation between the occurrence
of the parents and their degrades. Though public comment was requested,
triazines were not officially proposed for inclusion under UCMR 2
monitoring. There were no changes between the proposed and final rule
language, and thus, the triazines are not part of the UCMR 2 monitoring
requirements.
b. Summary of Major Comments
    Commenter opinion varied regarding inclusion of triazines in UCMR 2
monitoring. For those that supported their inclusion, the primary
reason was health effects. One of these commenters also recommended
that cyanizine be included in this contaminant group. Of those who
opposed including this group, the following reasons were given:

concern about laboratory capacity if two similar analyses using liquid
chromatography/tandem mass spectrometry (LC/MS/MS) were required to be
conducted in the same time frame; concern regarding the status of
method development; the belief that the manufacturer should pay for
occurrence testing; and the fact that information on the parent
compounds is already available.
    Although validation of a new triazine method has been completed,
EPA agrees that requiring the use of two LC/MS/MS methods in the same
UCMR cycle could present a laboratory capacity problem. Due to these
concerns, EPA has concluded that triazine monitoring should be
postponed until a future cycle of the UCMR.
8. Other Compounds That Were Considered
a. This Rule
    In identifying the target contaminants for this rule, EPA began
with a list of over 200 contaminants, compiled from a variety of
different sources, including: UCMR 1 reserved contaminants; CCL 1
deferred pesticides; CCL 1 suspected endocrine disruptors; and other
emerging contaminants. Through a multi-stepped review and
prioritization process, the list was narrowed and prioritized. EPA's
final prioritization was based on the available relative health effects
information for each compound.
b. Summary of Major Comments
    EPA received comment encouraging the Agency to include some
endocrine disruptors on the UCMR 2 contaminant list. The initial list
that EPA compiled included several contaminants that were identified as
suspected endocrine disruptors during CCL 1 development, as well as
others that are widely suspected to be endocrine disruptors. EPA used a
multi-stepped review and prioritization process to select 25
contaminants for monitoring from the broader pool of 200 contaminants.
Several different health effects criteria were used to prioritize
contaminants in addition to endocrine disruption, such as cancer
classification and toxicity. Although some contaminants that are
considered endocrine disruptors are not part of the final monitoring
list, all five flame retardants that are part of UCMR 2 are suspected
endocrine disruptors. In addition, EPA will consider these other
contaminants for monitoring in future rounds of UCMR monitoring.

D. How Are Laboratories Approved for UCMR 2 Monitoring?

1. This Rule
    The UCMR 2 laboratory approval process is designed to assess
whether laboratories meet the required equipment, laboratory
performance, and data reporting criteria. Laboratories wishing to
participate in UCMR 2 must contact EPA to be considered. This rule
requires laboratories to complete and submit their registration to EPA
by April 4, 2007 (i.e., within 90 days of final rule publication). To
be approved to conduct UCMR testing, this rule requires that the
laboratory be certified under Sec.  141.28 for one or more compliance
analyses; demonstrate, for each analytical method it plans to use for
UCMR testing, that it can meet the Initial Demonstration of Capability
(IDC) requirements and successfully participate in the UCMR Proficiency
Testing (PT) Program; and has the capability to post monitoring data to
EPA's electronic reporting system. Laboratories are encouraged to apply
for UCMR 2 approval as early as possible. The steps for the laboratory
approval process are as follows:
a. Request To Participate
    The laboratory must contact EPA requesting to participate in the
UCMR 2 laboratory approval process. Laboratories must send this request
to: UCMR 2 Laboratory Approval Coordinator, USEPA, Technical Support
Center, 26 West Martin Luther King Drive (MS 140), Cincinnati, OH
45268; or e-mail at<EMAIL_ADDRESS>EPA began
accepting participation requests for the methods associated with UCMR 2
(including List 1, Assessment Monitoring, and List 2, Screening Survey)
following publication of the proposed rule on August 22, 2005. The
laboratory must complete and submit the necessary registration by April
4, 2007.
b. Registration
    EPA will send each laboratory that requests a registration package
a list of information that EPA will need to process that application.
This registration information will provide EPA with the basic
information about the candidate laboratory including: Laboratory name;
mailing address; shipping address; contact name; phone number; fax
number; e-mail address; and UCMR 2 methods for which the laboratory is
seeking approval. Thus, the purpose of the registration step is to
ensure that EPA has all of the necessary contact information and that
each laboratory receives a customized application package, which will
include materials and instructions for the methods that it plans to
use.
c. Application Package
    When EPA receives the registration information, an application
package will be sent to the laboratory for completion. This application
package will be customized to address only those EPA methods selected
in the laboratory's registration. EPA may provide analytical standards
to be used when conducting monitoring; however, laboratories will be
required to procure their own standards, where commercially available,
to be used to complete the application process. Information requested
in the application will include:
     IDC data, including precision, accuracy, and MRL studies;
     Information regarding analytical equipment;
     Proof of current drinking water laboratory certification;
and
     Example chromatograms for each method under review.
    The laboratory must also confirm that it will post UCMR 2
monitoring results (on behalf of its PWS clients) to EPA's UCMR
electronic data reporting system.
d. EPA Review of Application Package
    EPA will review the application package and, if necessary, request
follow-up information. Satisfactory completion of this portion of the
process will allow the laboratory to participate in the UCMR 2 PT
program.
e. Proficiency Testing
    A PT sample is a synthetic sample containing a concentration of an
analyte that is known to EPA, but unknown to the laboratory being
tested. To complete the initial laboratory approval process, a
laboratory must successfully analyze UCMR 2 PT sample(s) for each
method for which the laboratory is seeking approval. A laboratory must
pass only one PT for each of the UCMR 2 methods. Laboratories applying
for UCMR 2 approval, and laboratories conducting UCMR 2 analyses, may
be subject to on-site laboratory audits. No PT studies will be
conducted after the start of monitoring. Laboratories will not be
approved if they did not successfully complete a PT study.
f. Written EPA Approval
    After the first five steps (a-e, above) have been successfully
completed, EPA will send the laboratory a letter listing the methods
for which approval is granted. These letters will also include a
reminder that the laboratory may be subject to on-site audits. A list
of

laboratories approved for UCMR 2 will be posted to EPA's UCMR Web site:
http://www.epa.gov/safewater/ucmr/ucmr2/labs.html.

2. Summary of Major Comments
    Several comments recommended that EPA continue to oversee the
laboratory approval process and offer PTs throughout the UCMR 2 period
to ensure that approved laboratories are maintaining data quality. EPA
notes that the laboratory approval process is meant to establish a list
of laboratories that have demonstrated their ability to perform the
Quality Assurance/Quality Control (QA/QC) requirements for UCMR 2
methods. EPA and its supporting contractor will be assisting candidate
laboratories to achieve the required proficiency during the laboratory
approval process. Once the approvals are completed, EPA does not intend
to invest the resources to maintain an ongoing laboratory monitoring
program. However, EPA will continue to provide technical assistance to
laboratories that request it. In addition, EPA will conduct a limited
number of on-site laboratory audits. PWSs also have a role to play in
data quality. In selecting a laboratory for conducting UCMR 2 analyses,
the PWS should consider the laboratory's commitment to data quality. As
a partner in the commitment to quality data, the PWS should request and
review the QC data associated with their UCMR 2 occurrence samples.
    Public comments also expressed concern that there may not be
adequate time for laboratories to receive certification, resulting in
reduced laboratory capacity at the onset of monitoring. Recommendations
included: Adjusting monitoring schedules in instances of inadequate
laboratory capacity; conducting the laboratory approval process prior
to rule promulgation; and extending the deadline for laboratories to
report monitoring results. EPA began offering the first round of
preliminary laboratory PTs in mid-2006. Additional rounds were
conducted before and are scheduled to be conducted after promulgation
of the final regulation. EPA is confident that sufficient laboratory
capacity will be available, but will also closely evaluate the results
of these preliminary PTs.
    In addition, this rule contains language that revises the Screening
Survey and Assessment Monitoring time frame to January 2008 through
December 2010. This revision extends the start date of UCMR 2
monitoring by 6 months from the proposed July 2007 start date and
allows the Screening Survey to be conducted across three years as
opposed to the two-year time frame that was proposed. This will allow
PWSs more time for UCMR 2 planning and budgeting and provide additional
assurance of sufficient laboratory capacity.

E. What Is A System's Responsibility Regarding the Use of Laboratories?

1. This Rule
    Under this rule, systems selected to participate in monitoring will
be required to use laboratories that are approved by EPA for UCMR 2
monitoring (see Section III.D, above). Large systems must ensure that
the laboratories conducting their analyses meet UCMR 2 QC requirements
and post the data in EPA's electronic data reporting system within 120
days of the sample collection date.
2. Summary of Major Comments
    Several comments were received regarding PWSs' responsibility for
laboratory compliance with QC and reporting requirements, indicating
that EPA should be responsible for ensuring laboratory compliance, as a
condition of certification.
    PWSs have always been responsible for the quality of the results
produced by the laboratory they employ, whether that monitoring was
conducted in support of UCMR 1 or compliance monitoring under SDWA.
Large PWSs (serving greater than 10,000 people) must ensure that their
laboratories have received appropriate EPA approvals to conduct UCMR 2
methods and must ensure that laboratories follow the specific UCMR 2 QC
requirements. EPA recommends that laboratory requirements be addressed
in the contractual language between the PWS and laboratory. EPA's UCMR
Web site at: http://www.epa.gov/safewater/ucmr/ucmr2 provides

informational materials that PWSs can use to help them evaluate their
data. These materials include: a laboratory approval manual, the
analytical methods (each of which contain a table summarizing QC
requirements of that method), and a general reference guide designed to
help PWSs develop laboratory contracts.

F. What Specific Quality Control Requirements Must Be Followed?

1. Method Development Approach and Method Defined Quality Control
a. This Rule
    Under this rule, UCMR 2 analyses will be conducted using five EPA
methods. This final rule revises several aspects of the methods QC
requirements compared to those that were established under UCMR 1,
including: revising the definition of and procedures for MRL detection
limits (see Section III.F.2. for more detail); and no longer requiring
QC samples because standards are generally not available. The final
rule language also contains other revisions to QC requirements that
were necessary because of the removal of perchlorate from the final
UCMR 2 monitoring list. See Section III.C.4 for a listing of those
changes.
b. Summary of Major Comments
    A few commenters were concerned that the methods have not been
properly validated, potentially increasing costs if repeat sampling is
needed. These commenters also believe that laboratory capacity would be
insufficient to conduct all required monitoring.
    As noted elsewhere, EPA is confident that the analytical method
validation procedures that it has followed provide the appropriate
evaluation of analytical methods and that the design of the Assessment
Monitoring and Screening Surveys ensures that adequate laboratory
capacity will be available. Moreover, as noted elsewhere, the final
rule extends the time frame for Screening Survey monitoring from two
years (as originally proposed) to three years, coinciding with
Assessment Monitoring. This extended timeframe will further enable
approved laboratories to handle the analyses associated with UCMR 2
monitoring.
    EPA received comments disagreeing with its proposal to no longer
require QC samples, arguing that this will diminish the quality of the
analyses, and that companies that manufacture QC standards will have
them available in 2006. A quality control sample, in this context, is a
primary dilution standard of methods analytes that is obtained from a
source external to the laboratory and different from the source of
calibration standards. Although EPA agrees that the periodic
measurement of a QC sample is an important element of standard
laboratory quality control, it is not feasible to require the use of QC
samples that do not currently exist and may or may not exist in the
future. In addition, all laboratories will be required to pass an EPA
performance study, which will help to assure the quality of the
calibration standards being used. However, EPA is strongly encouraging
all UCMR laboratories to analyze an independently prepared quantitative
standard on a quarterly basis. If commercially prepared QC standards
are available, they should be used. If not, laboratories should have a
second analyst prepare a separate set of quantitative standards to
serve as

independent quality control checks of the calibration standards being
used by the laboratory. EPA will continue to require that UCMR
laboratories analyze a variety of other samples (i.e., duplicate
samples, laboratory fortified reagent and matrix samples, etc.)
designed to assess the quality of their analyses, as specified in each
analytical method and in the ``UCMR 2 Laboratory Approval Manual''
(USEPA, 2004d).
2. Minimum Reporting Level
a. This Rule
    Under this rule, all laboratories certified to conduct UCMR
analysis must be able to demonstrate their ability to detect each UCMR
contaminant at the specified MRL. MRLs represent an estimate of the
lowest concentration of a compound that can be quantitatively measured
by a group of experienced drinking water laboratories. Previously, MRLs
had been determined by analytical laboratories using expert
professional judgment, but standard criteria for MRL determinations had
not been established. For this rule, EPA has revised the process for
developing MRLs as follows. The MRLs are now based on Lowest
Concentration Minimum Reporting Levels (LCMRLs) which were determined
by each laboratory that developed or subsequently tested the methods.
LCMRLs represent the lowest concentration of a compound that can be
quantitatively determined in each individual laboratory. In the
interest of greater consistency, EPA has developed a statistical
protocol for single-laboratory determinations of LCMRLs, using linear
regression and prediction intervals.
b. Summary of Major Comments
    Several comments were received regarding the number of significant
figures associated with the MRLs. These commenters wanted the number of
significant figures reduced. In considering public comments, EPA agrees
that the MRLs should be reported to one significant figure. The final
regulation contains revised language reflecting that MRLs are rounded
to one significant figure.
    Commenters also thought that having a different MRL for each
analyte may lead to calibration errors. They suggested revising the
MRLs within each method to achieve some proportional relationship among
the MRLs. EPA does not agree with this comment. The MRLs are based upon
a statistical analysis of the quantitation levels achieved at multiple
laboratories. To adjust those to some proportional level would be
arbitrary.
3. Lowest Concentration Minimum Reporting Level
a. This Rule
    EPA has developed a protocol for developing MRLs based on LCMRLs
determined by each laboratory that developed or subsequently tested the
methods listed in this action. For UCMR 1, EPA specified MRLs and a
requirement for recovery at the MRL so that data quality was documented
daily. In the interest of greater consistency, EPA developed a
statistical protocol for single-laboratory determinations of LCMRLs
using linear regression and prediction intervals. This approach has
been evaluated through expert peer review conducted in accordance with
the Agency's formal peer review process and through the performance of
a pilot-scale interlaboratory study. A free tool for calculating the
LCMRL was developed and is available for download on the Web: http://www.epa.gov/safewater/methods/sourcalt.html#Mlcmrl
.

b. Summary of Major Comments
    Some public commenters disagreed with the 50-150 percent acceptance
criteria for MRLs, arguing that it exceeds routinely accepted criteria,
and suggested instead to use  10-20 percent. EPA believes
that these commenters are referring to  10-20% relative
standard deviation (RSD) and notes that the MRL verification
requirement is based on the three sigma prediction interval being
within 50-150 percent. EPA believes that the 50-150 percent criteria is
in fact, a very stringent requirement comparable to that advocated by
the commenters. As an example, to meet the 50-150 percent criteria for
the 99 percent prediction interval, as specified in Sec.
141.40(a)(5)(iii), and assuming 100 percent accuracy, would require an
RSD of 13.5 percent. Since both precision and accuracy are measured by
this criterion, any errors in accuracy would serve to reduce the
required RSD even further, and make the precision criteria more
stringent.
    Other comments expressed concern that acceptance criteria were not
consistently applied, possibly leading to inconsistencies in the
precision and accuracy of reported values. EPA agrees that the LCMRL
process, as specified in the proposed regulation, does not apply
consistent acceptance criteria over the analytical range of the test
method. EPA has always recognized that precision and accuracy of
analytical methods are a function of concentration, and has generally
published differing acceptance criteria for its methods in recognition
of this fact. These concentration-based criteria do not in any way
represent a change in policy, rather, recognition of the reality of
analytical measurements.
4. Laboratory Fortified Sample Matrix and Laboratory Fortified Sample
Matrix Duplicate
a. This Rule
    Under this rule, all participating laboratories will be required to
analyze Laboratory Fortified Sample Matrix (LFSM) samples for accuracy,
and Laboratory Fortified Sample Matrix Duplicate (LFSMD) samples for
precision, for all UCMR 2 contaminants. LFSM/LFSMD samples must be
prepared using a sample collected and analyzed in accordance with UCMR
2 requirements and analyzed at a frequency of 5 percent (or one LFSM/
LFSMD set per every 20 samples) or with each sample batch, whichever is
more frequent. In addition, the LFSM/LFSMD fortification concentrations
must be alternated between a low-level fortification and mid-level
fortification approximately 50 percent of the time. The low-level LFSM/
LFSMD fortification concentration must be within  50
percent of the MRL for each contaminant, and the mid-level LFSM/LFSMD
fortification concentration must be within  20 percent of
the mid-level calibration standard for each contaminant. The low-level
method fortification level requirement of  50 percent
represents a revision to the proposed rule language based on public
comments that  20 percent was too restrictive.
b. Summary of Major Comments
    Some commenters expressed concerned about the added expense of
extra bottles and the time needed to coordinate with laboratories and
other utilities to ensure that the proper number of LFSM/LFSMD samples
will be submitted. Although EPA has changed the way that QC data will
be tracked, EPA has not changed the number of sample bottles which need
to be collected. The requirement to fortify at least one UCMR field
sample per analytical batch, and to report these data to EPA, has not
changed from UCMR 1. The only change compared to UCMR 1 is in how the
data are to be reported. Previously, laboratories were required to
report the percent recoveries of each analyte in the fortified field
samples; in UCMR 2 they are required to report the analytical result
and EPA will compute the recoveries.
    Other commenters suggested using the same sample for duplicates
instead of a second sample and using more

laboratory blanks to decrease cost. EPA notes that data from laboratory
blanks and fortified matrix samples provide very different information.
Data from fortified reagent water samples help the data user understand
how well the laboratory is performing the analysis. Fortified matrix
samples are used to determine if there are interfering compounds in the
matrix that preclude accurate analysis and to assess the precision and
accuracy of the database of field results. Since fortified reagent
water samples are not subject to the same type of matrix interferences
that field samples are, data from reagent water samples are not a
scientifically valid way to determine the precision and accuracy of
field data.

G. When Are Samples Collected?

1. This Rule
    To accommodate PWS preparation for rule implementation and to
provide additional assurance of sufficient laboratory capacity, this
rule contains revised language that changes the start of monitoring
from July 2007 to January 2008, such that the effective monitoring
period is now January 2008 through December 2010. This rule also
contains language that revises the Screening Survey time frame to match
that of Assessment Monitoring. Thus, Screening Survey systems will be
scheduled to monitor during a continuous 12-month period during January
2008 through December 2010.
    In addition, as under UCMR 1, ground water sampling points must be
monitored twice in a consecutive 12-month period. However, to provide
PWSs with more flexibility, the final rule contains revised language to
allow the second sampling event for ground water sampling points to
occur within 5-7 months of the first sampling event instead of within 6
months, as proposed. EPA will establish schedules for all systems to
ensure adequate laboratory capacity for the analysis of UCMR
contaminants and to improve the oversight of monitoring and data
reporting. EPA will use the State Monitoring Plans to identify all
systems that will participate in the UCMR 2 program, and to identify
the monitoring schedule for each system.
    This action also contains language that clarifies the definition of
a sampling location's source type. The final rule language specifies
that if any percentage of the total water associated with a sampling
point originates either from surface water or ground water under the
direct influence of surface water (GWUDI) during the 12-month
monitoring period, then that source should be reported as ``SW'' or
``GU'' as appropriate. These sampling points must be monitored for four
consecutive quarters, with sample events occurring three months apart
(e.g., a system could conduct monitoring in either: (1) January, April,
July, October; (2) February, May, August, November; or (3) March, June,
September, December).
2. Summary of Major Comments
    Many commenters did not support EPA's proposal to designate each
PWS's month and year of monitoring, expressing concern for budget and
scheduling, and some specific concerns that the assigned schedule could
conflict with the Initial Distribution System Evaluation (IDSE) that is
required under the Stage 2 DBPR. Alternatives recommended by commenters
included: setting a ``window'' in which monitoring must be completed;
allowing systems to conduct monitoring over the entire monitoring
period; and allowing systems to set their own schedules. Some
commenters recommended that EPA change the Screening Survey time frame
to match that of Assessment Monitoring; others recommended delaying the
start of the Screening Survey by one year. Based on its experience with
UCMR 1, EPA has determined that establishing a defined schedule (month
and year) for each PWS is necessary. Under UCMR 1, EPA did not
establish Assessment Monitoring schedules for large systems. This
resulted in delayed or incomplete monitoring for a number of large
systems, leading to enforcement actions that may have been avoided had
schedules been established. To help PWSs with scheduling and to provide
additional assurance of laboratory capacity, the final regulation
contains revised language that: (1) Changes the monitoring period for
UCMR 2 from July 2007 through June 2010 to January 2008 through
December 2010; and (2) extends the two-year monitoring period for the
List 2 Screening Survey contaminants to three years, such that the
Screening Survey will coincide with the three-year Assessment
Monitoring period of January 2008 through December 2010. In addition,
systems will have the opportunity to change their sampling schedules
either through EPA's electronic data reporting system by August 2,
2007, or after this date by fax, mail, or e-mail request to EPA.
    Some commenters indicated that wells may not be operating
continually and therefore, some systems with ground water sources will
be unable to meet EPA's schedule. Some recommended that EPA allow
systems to conduct the second sampling event within 5-7 months of the
first sample, as was done under UCMR 1. In response to this
recommendation, the final regulation contains revised language that
extends the time frame for collecting the second ground water sample to
5-7 months following the collection of the first round of samples. For
planning purposes, EPA will initially schedule these sampling events 6
months apart. However, systems will have the flexibility to sample
within a 5-7 month window. Systems will be required to notify EPA if
they cannot monitor within this 3-month window. Refer to Section
III.J.1.c for more detail on the requirement for a water system to
notify EPA if it is unable to monitor according to its assigned
schedule.

H. Where Are Samples Collected?

1. Entry Points to the Distribution System
a. This Rule
    This rule establishes that all UCMR 2 samples will be collected at
entry points to the distribution system (EPTDSs), and for nitrosamines,
within the distribution system, and eliminates the option of source
water monitoring (except for source water that leaves the EPTDS
untreated).
b. Summary of Major Comments
    Several commenters disagreed with EPA's proposal to eliminate
monitoring from ``raw source water'' samples. Several reasons were
given, including: Cost savings through coordination with compliance
monitoring; raw water samples would provide useful information for
determining which water treatment technologies are needed and potential
human exposure; and EPA allowed systems the option of sampling raw
water or EPTDS locations under UCMR 1. Other alternatives suggested
were to allow systems with multiple source water sampling locations to
collect a sample from the highest risk source based on their Source
Water Assessments, and to require a portion of large systems with
surface water sources to conduct raw water sampling under Assessment
Monitoring.
    In response to these comments, EPA notes that the UCMR design was
established in fulfillment of the 1996 SDWA Amendments (Section
1445(a)(2)), which states: ``The regulations shall require monitoring
of drinking water supplied by public water systems * * *'' The UCMR
program was designed to collect data that would provide information for
human exposure study. This is best achieved by conducting monitoring at
the EPTDS as opposed to a pre-treatment sampling

site. However, to provide flexibility during UCMR 1, systems were
allowed to collect ``raw source water'' samples in those States where
samples for regulated contaminants were collected prior to treatment.
If a system detected any contaminants above the MRL (and treatment was
subsequently applied), monitoring at EPTDSs was subsequently required.
This created substantial confusion and errant reporting during UCMR 1;
many systems did not fully understand or comply with the requirement to
conduct the required EPTDS monitoring following a raw water detection.
EPA anticipates that this confusion would be even more likely during
UCMR 2 if raw water monitoring was allowed because of the anticipated
occurrence rates for some UCMR 2 analytes. Moreover, since UCMR 2
methods are not used to support regulated contaminant monitoring, UCMR
2 samples cannot be used to meet compliance monitoring requirements.
2. Distribution System Maximum Residence Time
a. This Rule
    This rule requires systems that are participating in the Screening
Survey to collect nitrosamine samples both at EPTDSs and in the
distribution system to capture the occurrence of nitrosamines as
disinfection byproducts. This rule requires systems to collect their
nitrosamine samples at their distribution system maximum residence time
(DSMRT) location(s) for each treatment plant/water source as defined in
the Stage 1 DBPR. Water systems that do not have defined DSMRT sampling
points in the distribution system (e.g., systems that do not apply a
chemical disinfectant, wholesalers without retail customers) will be
required to collect nitrosamine samples at EPTDSs only.
b. Summary of Major Comments
    EPA requested comment on whether nitrosamines should be collected
at both EPTDSs and at the DSMRT for each treatment plant/water source
as defined in Stage 1 DBPR. A few commenters agreed that this
monitoring should occur at both sampling locations. Some commenters
disagreed with sampling finished water, saying that EPA will be unable
to determine whether NDMA occurs in the source or is formed as a
disinfection byproduct (DBP) without raw water data or information on
the disinfection level at the time of sample collection. In addition,
commenters pointed out that treatment can reduce the concentration of
some contaminants.
    EPA is requiring that nitrosamine samples be collected at two
locations to allow the Agency to evaluate whether exposure to
nitrosamines is influenced by the distribution system. Since the
nitrosamines may occur as source water contaminants and/or DBPs,
monitoring at both the EPTDSs and DSMRTs will provide EPA with the
range of human exposures to these contaminants in drinking water. In
addition, if a nitrosamine is present as a result of reactions with the
disinfectant, the concentration may increase the longer the water is in
contact with that disinfectant. EPA plans to compare the aggregated
concentration data from the two sample points to determine if there is
a significant difference in the concentrations. This information will
assist EPA in determining an appropriate sampling strategy if a
decision to regulate nitrosamines is made after the UCMR 2 exposure
information is available. EPA will also evaluate differences between
systems using free chlorine versus chloramines to determine if the type
of residual disinfectant is associated with nitrosamine levels.
    EPA agrees that the UCMR 2 data will not establish the source of
nitrosamines, if they are present in finished water. However, the
Agency does not agree that raw water data would necessarily establish
the source of nitrosamine contamination. Some coagulant aid polymers
used in drinking water treatment have been implicated as precursors of
nitrosamines. The inability to identify the source of the contaminant
is not limited to nitrosamines; it extends to all UCMR 2 contaminants.
The UCMR program was designed to collect data that would provide
information for human exposure study. This is best achieved by
conducting monitoring at the EPTDS as opposed to a pre-treatment
sampling site because the treatment process can influence the
concentration present in drinking water.
    Several public comments were received regarding the timing of UCMR
2 monitoring and the completion of IDSEs. Commenters were concerned
that most systems have not begun their IDSEs to identify the longest
residence time in their system, and thus, DSMRT locations may not be
available for nitrosamine occurrence testing. During UCMR 2
implementation, disinfecting systems will conduct monitoring at the
Stage 1 DBPR distribution system sampling locations. These locations
reflect the water system's and Primary Agency's judgment concerning
areas in the distribution system that have the ``oldest'' water (i.e.,
those locations with the greatest distribution system maximum residence
times or DSMRT). Under the Stage 2 DBPR, systems will be required to
conduct IDSEs to determine locations with representative high total
trihalomethanes (TTHM) and haloacetic acids (HAA5) concentrations. EPA
agrees that new information collected during the IDSE study may result
in the water system no longer using the Stage 1 DSMRT sampling
locations because other areas of the distribution system may have
higher concentrations of TTHM or HAA5. However, EPA believes it is
still appropriate to use the Stage 1 DSMRT sample locations for the
UCMR 2 monitoring because it is premature to link nitrosamine
occurrence levels to TTHM and HAA5 levels. In addition, no water system
is required to conduct Stage 2 compliance monitoring until 2012, long
after UCMR 2 monitoring is complete.

I. How Should Samples Be Collected?

1. This Rule
    This rule includes clarifying language that acetanilide parent
compounds and their degradates must be collected at the same time and
sampling location (Sec.  141.40(a)(4)(i)(D)). Refer to Section III.C.2
for a more detailed discussion of comments pertaining to acetanilides.
This rule also revises system resampling requirements related to
laboratory errors or sampling deviations (Sec.  141.40(a)(4)(i)(G)).
Previously, systems were required to resample within 14 days of
becoming aware of a sampling or laboratory error. Systems will now have
30 days to collect the resample. This rule also retains the instruction
that sample collection and shipping take place Monday-Thursday to
ensure that samples arrive at the laboratory at the required
temperature.
2. Summary of Major Comments
    EPA agreed with comments that recommended acetanilide parent and
the degradation products analysis be conducted using samples collected
in the same location, and at the same time, to provide data on their
relative concentrations. The final regulation contains revised language
to specify that acetanilide parent and degradation product sampling be
conducted at the same time and at the same site.
    Several public comments were received indicating that a resampling
period of 14 days is too short. Some made recommendations for extending
the period to within 30 days of receiving written notification that a
laboratory error had occurred or after the system determines that a
sampling error has

occurred. Others recommended up to two months. In response to these
comments, EPA has included revisions to the final regulation requiring
resampling to occur within 30 days of being informed or becoming aware
of the sampling or laboratory error. Extending the resampling period
beyond 30 days would result in a large number of resamples being
collected in the next quarterly monitoring period.

J. What Are the UCMR 2 Reporting Requirements?

1. Information Required Prior to Monitoring
a. Contact Information
    This rule finalizes the proposed requirement for water systems to
report contact information (i.e., the name, affiliation, mailing
address, phone number, fax number, and e-mail address of the PWS
Technical Contact and PWS Official) to EPA. Large systems (those
serving 10,000 or more people) must submit this information by April 4,
2007 using EPA's electronic data reporting system. Small systems, or
States (if acting on their behalf) must submit this information within
90 days of receiving a letter from EPA that requests contact
information. EPA did not receive any comments regarding these
requirements.
b. Sampling Location and Inventory Information
i. This Rule
    This rule finalizes the proposed requirement for large PWSs to
provide inventory information for each of their required sampling
locations by August 2, 2007 (i.e., within 210 days of final rule
publication) using EPA's electronic reporting system. For each sampling
location, or for each approved representative sampling location, large
systems must submit the following: public water system identification
(PWSID) code; PWS facility identification code; sampling point
identification code; sampling point type code; and sampling location
water type. Any changes to these data must be reported to EPA's
electronic reporting system within 30 days of the change. Section
III.J.3.b of this action includes a more detailed discussion of EPA's
electronic reporting system.
    ii. Summary of major comments
    Some commenters recommended that existing inventory information
from the Safe Drinking Water Accession and Review System (SDWARS) or
other databases, such as EPA's Safe Drinking Water Information System
(SDWIS), be used to pre-populate the database for UCMR 2 to reduce some
of the burden on water systems. EPA will use the large system inventory
that is currently stored in SDWARS 1 as much as possible, and
supplement that with new entry point facilities from SDWIS, as well as
new information provided by the State. PWSs will be responsible for
verifying, correcting, and updating inventory information. PWSs will
identify the facilities/sample points that are required to be sampled
(i.e., all EPTDSs or approved representative EPTDSs sampling points, as
well as applicable DSMRT sampling points). PWSs that are required to
monitor in the distribution system will have the opportunity in SDWARS
to associate the distribution system sample point with an entry point.
c. Proposals for Representative Sampling Locations
i. This Rule
    Under this action, some large systems that have multiple ground
water EPTDSs can request approval to monitor at representative entry
point(s) rather than at each EPTDS. Large PWSs can submit either
documentation of alternate EPTDS sampling locations that were approved
by the State or EPA for UCMR 1 or Phase II/V monitoring, or a proposal
for sampling at representative EPTDS(s), with supporting documentation
to demonstrate that any EPTDS selected as representative of the ground
water supplied from multiple wells is associated with an individual
well that draws from the same aquifer as the multiple wells (i.e.,
those being represented).
ii. Summary of Major Comments
    Many commenters agreed with EPA's proposal to allow ground water
systems to use representative entry points. Some indicated that EPA
should allow more flexibility in the type of data used to support the
selection of representative EPTDSs. In particular, some commenters
suggested that EPA allow any previously approved representative
monitoring plans used for UCMR 1 (including those approved by EPA) as
appropriate documentation. Commenters also indicated that some systems
may need more than 210 days after the publication date to prepare a
representative well proposal and that EPA should extend this deadline.
    In response to comments, the final regulation contains revised
language to allow PWSs to submit documentation of a representative well
plan approved in previous UCMR cycles (Sec.  141.35(c)(3)(i)). However,
EPA is not revising the rule language that lists examples of the types
of information a PWS may submit to demonstrate the representativeness
of a well (Sec.  141.35(c)(3)(ii)). The situation and available data
will vary too widely from PWS to PWS for EPA to specify the exact data
that are necessary. Further, EPA believes that the time frame for
submitting representative proposals is reasonable and notes that
systems were made aware of this opportunity shortly after the
publication of the proposed rule.
d. Reporting/Coordination of Monitoring Schedules for Large Systems
i. This Rule
    Under UCMR 2, EPA will establish monitoring schedules for all
participating systems. Large systems have until August 2, 2007 (i.e.,
210 days from the publication of this final rule) to revise their
schedule using the EPA electronic data reporting system. After August
2, 2007, if a large PWS cannot sample according to the required
schedule, the PWS Official must fax, mail, or e-mail a request to EPA
explaining the reason samples cannot be taken according to the assigned
schedule and requesting an alternative schedule. This rule also
contains revised language clarifying that the second set of samples
from ground water sources may be collected any time within 5-7 months
of the first sampling event without the PWS being required to notify
EPA.
ii. Summary of Major Comments
    Some commenters recommended that the 210-day deadline for
submitting a revised monitoring schedule be removed and systems be
allowed to conduct monitoring at any time during the entire three-year
time frame. Commenters indicated that the deadline would limit a water
system's ability to coordinate its monitoring schedule with a contract
laboratory's analytical capacity, and would result in an increased
likelihood of monitoring and reporting violations due to operational
failures beyond the water system's control. As discussed in Section
III.J.1.d of this preamble, EPA will establish a defined schedule
(month and year) for each PWS. During the 210-day period following
publication of the final regulation (i.e., August 2, 2007), a PWS can
simply revise its schedule using the EPA electronic data reporting
system. Barring a serious problem with large numbers of PWSs wanting to
change their scheduled monitoring to the same time frame, EPA will
honor all of these requests. After August 2, 2007, a PWS may request
that its schedule be changed; however, unlike the first 210-day period,
the PWS will need to

explain its rationale for the requested change. Budgetary issues or
well closings are examples of problems that will be considered
legitimate reasons for schedule changes. A system is subject to its
original assigned sampling schedule or its modified schedule
established prior to August 2, 2007 via EPA's electronic data reporting
system, unless and until it receives notification from EPA specifying a
new schedule.
    To help PWSs with scheduling and to provide additional assurance of
laboratory capacity, the final regulation contains revised language
that: (1)Changes the monitoring period for UCMR 2 from July 2007
through June 2010 to January 2008 through December 2010; and (2)
extends the two-year monitoring period for the List 2 Screening Survey
contaminants to three years, such that the Screening Survey will
coincide with the three-year Assessment Monitoring period of January
2008 through December 2010. In addition, because of the logistical
issues associated with sampling for UCMR 2 (e.g., seasonal operation of
some wells), the final regulation also contains revised language that
extends the time frame for collecting the second ground water sample to
5-7 months following the collection of the first round of samples. This
will allow systems that have multiple sampling points to schedule the
second sampling event across the 5-7 month window. However, for
planning purposes, EPA will preliminarily schedule these sampling
events 6 months apart.
    e. Notice regarding applicability or inability to meet sampling
schedule
i. This Rule
    This rule includes system reporting requirements to ensure
communication between PWSs and EPA regarding rule applicability and
compliance. These requirements include: reporting changes in system
status or other factors that affect a system's requirements under the
rule (e.g., a system believes it does not meet the applicability
criteria for UCMR); notifying EPA if a system believes it is subject to
UCMR requirements but has not been notified by either EPA or the State
regarding requirements; and reporting to EPA if a system cannot sample
according to its assigned schedule. The final regulation at Sec.
141.35(c)(5) contains revised language to clarify that systems
collecting samples from ground water sources can collect their second
set of samples within the 5-7 months of the first sampling event.
ii. Summary of Major Comments
    Some commenters suggested that EPA develop a list of acceptable
reasons for not monitoring from a source to eliminate the need for
systems to notify EPA. EPA believes that it is impractical to develop
an exhaustive list. It is important that EPA be notified of any reason
that a scheduled sampling event will be missed to allow for effective
coordination of compliance assistance and enforcement actions.
2. Reporting of Required Data Elements
a. This Rule
    This rule specifies 15 data elements in Sec.  141.35(e), Table 1,
to be reported with UCMR 2 sample test results. In this table, EPA is
providing clarifying language to the following four data elements:
Water Source Type (data element 3); Sampling Point
Identification Code (data element 4); Sampling Point Type Code
(data element 5); and Disinfectant Residual Type (data element
6). EPA received comments on Sample Analysis Type (data
element 11) and Sample Event Code (data element 15)
but did not revise these data elements in this action.
b. Summary of Major Comments
    Comments were received questioning whether systems would be
required to report source water changes that occur throughout the 12-
month monitoring period or only those that occur between sampling
events. To simplify UCMR 2 reporting, the definition of ``Water Source
Type'' (data element 3) contains revised language specifying
that if any percentage of the total water associated with that sampling
point originates either from surface water or GWUDI source during the
12-month monitoring period, then that source should be reported as
``SW'' or ``GU'' as appropriate. If a sampling point is served by both
a surface water and GWUDI source during the 12-month monitoring period,
then that source should be reported as SW (i.e., SW takes precedence
over GU in the hierarchy of source water reporting). The only time that
a source is to be considered ground water is if 100 percent of the
water associated with that sampling point is from a ground water source
during the entire 12-month monitoring period. By defining a sampling
point source over the entire 12-month monitoring period, many instances
where a system would otherwise need to report a change in its source to
EPA will be eliminated.
    Some commenters indicated that definitions for Sampling Point
Identification Code (data element 4), and Sampling Point Type
Identification Code (data element 5), seem redundant. In
response to comments, the final regulation contains revised language
changing the name of data element 5 to ``Sampling Point Type
Code'' and clarifying the definitions of these two data elements.
    Some commenters recommended that EPA clarify the definition of
``Disinfectant Residual Type'' (data element 6) because some
systems may periodically use an alternate disinfectant. EPA's intent in
the proposed rule language was that PWSs would report the type of
disinfectant used at the time of each specific sampling event. In
response to this comment, the final rule contains revised language to
Table 1 of Sec.  141.35(e) to clarify this point.
    Some commenters expressed concern that EPA will create
inconsistencies in water system and laboratory databases by retaining
the name ``Sample Analyses Type'' from UCMR 1 but changing the codes
associated with it. EPA revised the codes associated with this data
element (11) to better reflect the type of sample collected.
The values that laboratories used previously proved to be problematic,
since laboratories did not have enough information about the PWS's
treatment systems or sample locations to assign the correct sample
analysis type. Instead, EPA proposed and is finalizing in this rule
codes that will provide EPA with QC information at the field sample
level and with information about which UCMR field sample was fortified.
3. Reporting Process
a. Where to Report
    This rule specifies in Sec.  141.35(b)(1) the Web address for
information that must be submitted electronically as: http://www.epa.gov/safewater/ucmr/ucmr2/reporting.html.
 This paragraph of the

final rule also specifies that supporting documentation can be
submitted to: UCMR Sampling Coordinator, USEPA, Technical Support
Center, 26 West Martin Luther King Drive (MS 140), Cincinnati, OH
45268; or by e-mail at<EMAIL_ADDRESS>or by fax
at<PHONE_NUMBER>. EPA did not receive any comments related to this
aspect of the rule.
b. Electronic Reporting System
i. This Rule
    EPA's electronic data reporting system--called SDWARS, which can be
accessed on the Web at: http://www.epa.gov/safewater/ucmr/ucmr2/reporting.html_is
 the primary portal for PWSs and laboratories to

submit contact

and inventory information to EPA. The UCMR program requires that all
monitoring results and associated data elements be reported using this
system. There were no changes between the proposed and final rule
language regarding this data reporting system. The data review and
approval process is discussed in Section III.J.3.c.
ii. Summary of Major Comments
    EPA received several recommendations to provide more information
and guidance related to PWS and laboratory use of its electronic data
reporting system. In addition, several commenters requested that EPA
pre-populate the UCMR 2 database with contact and inventory information
that was collected under UCMR 1, or that it be easily accessible
through EPA's SDWIS database.
    EPA is not pre-populating the SDWARS 2 database with PWS contact
information for two reasons. First, the data that EPA currently has on
file are several years old and EPA is aware that many changes in
contact information are necessary. Second, EPA will use a PWS's entry
of this information into SDWARS to confirm that the system has
successfully set up its SDWARS account. However, EPA will upload all
inventory information that it has available (i.e., PWS identification
code; PWS facility identification code; sampling point identification
code; sampling point type code; and sampling location water type). PWSs
will be responsible for verifying, correcting, and updating inventory
information, as needed. In addition, EPA is finalizing the specific
process for the upload of monitoring results and will release the
details of the process and upload files as far ahead of the start of
monitoring as possible.
    Some comments were received expressing concern about the stability
of the UCMR 1/SDWARS 1 database, claiming that data was lost which
caused unnecessary notices of violation to be issued. Comments
suggested that reminder letters/notices for compliance assistance would
be more effective. Other comments were received suggesting that, to
minimize confusion, PWSs have the option to report using the process
they already use to report to their States, and States would then
report to EPA.
    EPA is not aware of any cases in which SDWARS lost data. In
general, where data appeared to be lost, closer review revealed other
reasons for the problem, including various situations that resulted in
data that was not officially ``approved'' or data transfer errors by
laboratories that caused SDWARS to reject all or parts of files. When
developing UCMR 1 and the overall UCMR program, EPA was concerned about
the problem of transcription errors in data reporting. Therefore, EPA
designed SDWARS such that the originator (i.e., the laboratory that
performed the analysis) was responsible for entering the data into the
database.
c. Data Review and Approval Process/Timeline
i. This Rule
    This rule requires large systems to ensure that their laboratory
posts the data in EPA's electronic data reporting system (http://www.epa.gov/safewater/ucmr/ucmr2/reporting.html
) within 120 days from

the sample collection date. Large systems then have 60 days from when
the laboratory posts the data in EPA's electronic data reporting system
to review, approve, and submit the data to the State and EPA via the
EPA electronic reporting system. If systems do not take action on the
data within 60 days of the laboratory's posting to the electronic
reporting system, the data will be considered approved by the system,
and available for EPA review, and subsequent public release.
    Because EPA pays for and organizes the small system testing
program, the review and approval steps for small systems differ. Small
systems are only required to record system and sample location
information on the sampling forms and bottles that are sent to them by
the UCMR Sampling Coordinator. Procedures for submitting this
information will be specified in the instructions sent to the system.
Small systems are not required to review monitoring results, although
they will be given a 60-day opportunity to review such results prior to
their results being posted to the publicly available Web site.
ii. Summary of Major Comments
    Several commenters expressed that PWSs could not be held
responsible for laboratory compliance with the UCMR 2 reporting
requirements. Section 141.35(c)(6)(ii) specifies that PWSs must ensure
that their laboratories post the required data to the electronic
database within 120 days of sampling. PWSs have the responsibility to
require that their laboratory meets this reporting deadline and PWSs
are ultimately responsible for ensuring the quality of their data.
    Regarding compliance with review and approval timelines, commenters
also were concerned that unnecessary enforcement notices were issued
during UCMR 1 often because PWSs had not correctly processed and
approved data through SDWARS. Several commenters recommended that
reminder notices would help to ensure reporting compliance during UCMR
2 and reduce the need for enforcement actions. Other commenters were
concerned about laboratory capacity and the ability of a limited number
of approved laboratories to successfully conduct analyses and reporting
within the required time frames.
    EPA is currently in the final stages of developing the SDWARS
electronic data entry system for entry of UCMR 2 monitoring results and
is including an automatic e-mail system that will alert PWSs that data
was entered by the laboratory, thereby reminding PWSs that they need to
review and approve their monitoring data.
4. Cross-Media Reporting and Data Availability
a. Cross-Media Electronic Reporting
    The reporting required under this final rule is consistent with the
requirements of the October 13, 2005, regulation, ``Cross-Media
Electronic Reporting'' (70 FR 59847, (USEPA, 2005b)).
b. Data Availability
    The data collected through the UCMR program is being stored in NCOD
to facilitate analysis and review of contaminant occurrence; to guide
the conduct of the CCL process; and to support the Administrator's
determination to regulate a contaminant in the interest of protecting
public health, as required under SDWA Section 1412(b)(1). Results of
the UCMR 1 monitoring can be viewed by the public at EPA's UCMR Web
site: http://www.epa.gov/safewater/ucmr/data.html.

K. What Constitutes a Violation Under UCMR 2?

    Under this rule, EPA will finalize the definitions for monitoring
and reporting violations as proposed. A monitoring violation under UCMR
2 is defined as: ``Any failure to monitor in accordance with Sec. Sec.
141.40(a)(3)-(5) is a monitoring violation.'' A reporting violation is
defined as: ``Any failure to report in accordance with Sec.  141.35 is
a reporting violation.'' EPA did not receive any comments related to
these violation definitions.

L. Technical Correction Rule Changes in This Rule

    This rule includes two technical corrections pertaining to:
Aldicarb monitoring and State primacy.

1. Changes Pertaining to Aldicarb Monitoring
    When EPA published ``Revisions to the Unregulated Contaminant
Monitoring Regulation for Public Water Systems; Final Rule,'' on
September 17, 1999 (64 FR 50556, (USEPA, 1999)), two references to
Sec.  141.40 in Sec.  141.24 became obsolete, but were not corrected in
the 1999 rule. EPA is correcting this technical error by revising the
references to requirements for monitoring for aldicarb, aldicarb
sulfone, and aldicarb sulfoxide in Sec.  141.24(h) and Sec.
141.24(h)(7)(v). EPA suspended monitoring for these regulated
contaminants in a 1992 Federal Register notice (57 FR 22178, May 27,
1992 (USEPA, 1992)), and there are no monitoring requirements for these
contaminants under UCMR.
2. Changes Pertaining to State Primacy
    Section 553 of the Administrative Procedure Act, 5 U.S.C.
553(b)(B), provides that, when an agency for good cause finds that
notice and public procedure are impracticable, unnecessary or contrary
to the public interest, the agency may issue a rule without providing
prior notice and an opportunity for public comment. In today's final
rule, EPA is removing the reference to Sec.  141.40 in Sec.  142.16(e),
a portion in the Code of Federal Regulations (CFR) that enumerates the
sections of the CRF subject to State primacy. The reference was first
removed on September 17, 1999 (64 FR 50556, (USEPA, 1999)), when EPA
published ``Revisions to the Unregulated Contaminant Monitoring
Regulation for Public Water Systems; Final Rule.'' However, in EPA's
subsequent publication of the ``Arsenic and Clarifications to
Compliance and New Source Contaminants Monitoring Final Rule'' (66 FR
6975, January 22, 2001, (USEPA, 2001b)), the Agency inadvertently
reinserted the reference to Sec.  141.40 in Sec.  142.16(e). EPA has
determined that there is good cause for making this rule change final
without prior proposal and opportunity for comment because removal of
this reference was the product of a prior notice-and-comment
rulemaking, (see 64 FR 50556, (USEPA, 1999)) and because the reference
to UCMR monitoring is erroneous and no longer has any substantive
effect. Thus, notice and public procedure are unnecessary. EPA finds
that this constitutes ``good cause'' under 5 U.S.C. 553(b)(B). For the
same reasons, EPA is making this rule change effective upon
publication.

IV. State and Tribal Participation

A. Partnership Agreements

1. This Rule
    Under UCMR 2, States may continue to have a role in rule
implementation through Partnership Agreements (PAs). Because specific
activities for individual States are identified and established through
the PAs, not through rule language, this rule does not contain
reference to PAs.
2. Summary of Major Comments
    Comments received regarding State participation in UCMR 2
included:Recommendations that non-partnering States have an opportunity
to review State Monitoring Plans; concerns regarding State resources to
help implement UCMR 2; and the need for more guidance from EPA
regarding PAs, including the need for a template for the sampling
protocols for States to use as the basis for their water system
notification. EPA sent the draft State Monitoring Plans to all States
prior to the negotiation of PAs. All States that agreed to partner with
EPA were asked to review and provide any needed revisions to the draft
plan. Each State could agree to accept additional responsibilities as
documented through each State's final PA with EPA. In addition, EPA
will provide States with guidance and templates for small system
instructions.

B. Governors' Petition and State-Wide Waivers

    This rule retains the UCMR 1 language that, consistent with SDWA,
allows a minimum of seven State Governors to petition EPA to add
contaminants to the UCMR Contaminant list. This rule also retains the
UCMR 1 language that allows States to waive monitoring requirements
with EPA approval and under very limited conditions. EPA did not
receive any comments on either of these topics.

V. Cost and Benefits of This Rule

    In this rule, EPA finalized a new set of contaminants for
monitoring in the second five-year UCMR cycle of 2007--2011. UCMR 2
Assessment Monitoring (for List 1 contaminants) will be conducted from
January 2008 through December 2010 by 800 systems serving 10,000 or
fewer, and by all systems serving more than 10,000 people. The
Screening Survey for List 2 contaminants will also be conducted from
January 2008 through December 2010 by 800 systems serving 100,000 or
fewer, and all systems serving more than 100,000 (approximately 400
systems). Small systems (those serving 10,000 or fewer people) will not
be subject to more than one component of UCMR 2 monitoring. For cost
estimation purposes, EPA assumes that one-third of systems will monitor
during each of the three monitoring years (2008-2010).
    Labor costs pertain to systems, States, and EPA. They include
activities such as reading the regulation, notifying systems selected
to participate, sample collection, data review, reporting, and
recordkeeping. Non-labor costs will be incurred primarily by EPA and by
large PWSs. They include the cost of shipping samples to laboratories
for testing and the cost of the actual laboratory analyses.
    In this rule, EPA specified five analytical methods to monitor for
25 new UCMR contaminants. Estimated system and EPA costs are based on
the projected analytical costs for these methods. With the exception of
Method 525.2, these methods are comparatively new and will not coincide
with other compliance monitoring (e.g., no cost savings for coincident
monitoring can be realized). Laboratory analysis and shipping of
samples account for approximately 71 percent of the national cost for
UCMR 2 implementation. These costs are calculated as follows: The
number of systems, multiplied by the number of sampling locations,
multiplied by the sampling frequency, multiplied by the cost of
laboratory analysis. Under UCMR 2, surface water (and GWUDI) sampling
points will be monitored four times during the applicable year of
monitoring, and ground water sampling points will be monitored twice
during the applicable year of monitoring. Screening Survey systems that
are required to monitor for DBPs will be required to sample for
nitrosamines at one distribution system sampling point per treatment
plant (i.e., at the DSMRT), as well as their EPTDS sampling locations.
    Following publication of the proposed rule, and EPA's initial cost
and burden estimates, EPA received several cost-related public
comments. Several public commenters felt that EPA's estimates of cost
and burden (e.g., laboratory, shipping fees and estimated labor burden)
to PWSs were too low.
    During the proposed rule and Information Collection Requirement
(ICR) development, EPA estimated laboratory fees based on consultations
with several national drinking water laboratories and based on costs of
similar analytical methods. In response to comments, EPA revisited the
estimates of UCMR 2 method pricing. EPA approached three additional
national drinking water laboratories

(different than those consulted previously) and requested pricing
estimates for UCMR 2 methods. EPA averaged the pricing estimates from
the laboratories that were consulted into the cost estimates. EPA also
revisited key shipping company pricing lists to ensure that shipping
cost assumptions were as accurate as possible.
    With respect to per system burden estimates, EPA notes that all
burden estimates represent average burden hours, which include surface
water systems that may have very few sampling points, and thus lower
sampling burden, as well as those systems with higher numbers of
sampling points that would therefore have greater sampling activity
labor burden. Moreover, a system's burden is primarily incurred during
its one year of required UCMR monitoring (between January 2008 and
December 2010). However, in compliance with the requirements of the
Paperwork Reduction Act (44 U.S.C. 3501 et seq.), these cost and burden
estimates are presented as an average over the applicable three-year
ICR period (2007-2009). Small systems (those serving 10,000 or fewer
people) will have the lowest burden not only because of the relative
smaller size of their infrastructure, but also because these systems
will receive a great deal of direct assistance from EPA and/or their
State.
    EPA estimates of laboratory fees are based on the average cost
determined through consultations with national drinking water
laboratories, unit costs are as follows:

------------------------------------------------------------------------

------------------------------------------------------------------------
Assessment Monitoring (List 1):
  EPA Method 527 (for 7 contaminants).........................      $220
  EPA Method 529 (for 3 contaminants).........................       215
                                                               ---------
    Total List 1..............................................       435
                                                               ---------
Screening Survey (List 2):
  EPA Method 521 (for 6 contaminants).........................       310
  EPA Method 535 (for 6 contaminants).........................       370
  EPA Method 525.2 (for 3 contaminants).......................       190
                                                               ---------
    Total List 2..............................................       870
------------------------------------------------------------------------

    Shipping is added to the calculated costs to derive the total
direct analytical non-labor costs. Estimated shipping costs were based
on the average cost of shipping a 15-pound package overnight, plus a
ground shipment cost of the empty package which is sent to the PWSs
prior to their required sampling.
    In preparing the UCMR 2 ICR, EPA relied on standard assumptions and
data sources used in the preparation of other drinking water program
ICRs. These include the PWS inventory, number of sampling points per
system, and labor rates. EPA expects that States will incur only labor
costs associated with UCMR 2 implementation. State costs were estimated
using the relevant modules of the State Resource Model that was
recently developed by the Association of State Drinking Water
Administrators (ASDWA) in conjunction with EPA (ASDWA, 2003) to help
States forecast resource needs. Model estimates were adjusted to
account for actual levels of State participation under UCMR 1. Because
State participation is determined through the PAs, level of effort will
vary across States and depend on their individual agreements with EPA.
    Over the UCMR 2 cycle of 2007-2011, EPA estimates that nationwide,
the average annual cost of UCMR 2 is approximately $8.87 million. These
total estimated annual costs and total estimated costs (labor and non-
labor) are incurred as follows:

------------------------------------------------------------------------
                                              Average          Total
                                            annual cost      estimated
               Respondent                     for all      costs for all
                                            respondents     respondents
                                            (2007-2011)     (2007-2011)
------------------------------------------------------------------------
Small Systems serving 25--10,000,                $0.06 m           $0.30
 including labor only (non-labor costs
 are paid for by EPA)...................
Large Systems serving 10,001--100,000,            3.84 m           19.20
 including labor and non-labor costs....
Large Systems serving 100,001 and                 1.91 m            9.55
 greater, including labor and non-labor
 costs..................................
States, including labor costs related to          0.49 m            2.45
 implementation coordination............
EPA, including labor for implementation           2.57 m           12.85
 coordination and non-labor for small
 system testing.........................
                                         -------------------------------
    National Total......................          8.87 m           44.35
------------------------------------------------------------------------

    Additional details regarding EPA's cost assumptions and estimates
can be found in the ICR Number 2192.01 amendment prepared for the final
rule (OMB number 2040-0270), which presents estimated cost and burden
for the 2007-2009 monitoring period. Estimates of costs over the entire
second five-year UCMR cycle of 2007-2011 are attached as an appendix to
the ICR. Copies of the ICR and its amendment may be obtained from the
EPA public docket for this rule, which includes this ICR, under Docket
ID Number OW-2004-0001.

VI. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review

    Under Executive Order (EO) 12866 (58 FR 51735, October 4, 1993),
this action is a ``significant regulatory action.'' Accordingly, EPA
submitted this action to the Office of Management and Budget (OMB) for
review under EO 12866 and any changes made in response to OMB
recommendations have been documented in the docket for this action.

B. Paperwork Reduction Act

    OMB has approved the information collection requirements contained
in this rule under the provisions of the Paperwork Reduction Act, 44
U.S.C. 3501 et seq. and has assigned OMB control number 2040-0270.
    The information to be collected under this rule fulfills the
statutory requirements of Section 1445(a)(2) of SDWA, as amended in
1996. The data to be collected will describe the source of the water,
location, and test results for samples taken from PWSs. The
concentrations of any identified UCMR contaminants will be evaluated
with respect to health effects and those contaminants will be
considered for future regulation accordingly. Reporting is mandatory.
The data are not subject to confidentiality protection.
    The annual burden and cost estimates described below are for the
implementation assumptions described in Section V, Cost and Benefits of
the Rule, of this action. Respondents to the

UCMR 2 will include 1,280 small water systems (those serving 10,000 or
fewer people; 800 for Assessment Monitoring and 480 for Screening
Survey monitoring), the 3,633 large PWSs (those serving more than
10,000 people), and the 56 States and primacy agencies (4,969 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. Cost estimates assumes
that most Assessment Monitoring and Screening Survey systems will
conduct sampling evenly across the January 2008-December 2010
monitoring period (i.e., one-third in each of the three consecutive 12-
month periods). Because the applicable ICR period is 2007-2009, only
two years of core monitoring activity are captured in the ICR
estimates. Some rule preparation, including reporting of contact and
inventory information, will occur during 2007.
    Small systems (those serving 10,000 or fewer) that are selected for
UCMR 2 monitoring will sample an average of 1.8 times per system (i.e.,
number of responses per system) across the three-year ICR period of
2007-2009. The average burden per response for small systems is
estimated to be 3.5 hours. Large systems serving 10,001 to 100,000
people and large systems serving more than 100,000 people will sample
and report an average of 2.0 and 2.4 times per system, respectively,
across the three-year ICR period of 2007-2009. The average burdens per
response for these two categories of large systems are estimated to be
9.8 and 15.2 hours, respectively. The larger burden per response for
the largest systems reflects the fact that these systems typically have
more sampling locations. States are assumed to have an average of 1.0
response per year, related to coordination with EPA and systems, with
an average burden per response of 203.2 hours. In aggregate, during the
ICR period of 2007-2009, the average response (including responses from
both systems and States) is associated with a burden of 12.1 hours,
with a labor plus non-labor cost of $2,170 per response.
    The annual average per respondent burden hours and costs for the
ICR period of 2007-2009 are: small systems--2.1 hour burden at $57 for
labor; large systems serving 10,001 to 100,000--6.6 hours at $197 for
labor, and $1,651 for analytical costs; large systems serving more than
100,000--12.1 hours at $431 for labor, and $4,840 for analytical costs;
and States--203.2 hours at $11,107 for labor. Annual average burden and
cost per respondent (including both systems and States) is estimated to
be 8.1 hours, with a labor plus non-labor cost of $1,456 per
respondent. Note that small systems do not pay for testing costs, so
they only incur labor costs. The total annual burden for the ICR
reporting period of 2007-2009 is 40,386 hours (with a labor cost of
$1.51 million); the total annual analytical cost is $5.73 million.
    The Agency estimates the annual burden to EPA for UCMR program
activities during the ICR years of 2007-2009 to be approximately 9,533