EPA 815-Z-03-005
Monday,
August 18, 2003
Part II
Environmental
Protection Agency
40 CFR Parts 141, 142, and 143
National Primary Drinking Water
Regulations: Stage 2 Disinfectants and
Disinfection Byproducts Rule; National
Primary and Secondary Drinking Water
Regulations: Approval of Analytical
Methods for Chemical Contaminants;
Proposed Rule
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
ENVIRONMENTAL PROTECTION
AGENCY
40 CFR Parts 141,142 and 143
[FRL-7530-3]
RIN 2040-AD38
National Primary Drinking Water
Regulations: Stage 2 Disinfectants and
Disinfection Byproducts Rule; National
Primary and Secondary Drinking Water
Regulations: Approval of Analytical
Methods for Chemical Contaminants
AGENCY: Environmental Protection
Agency.
ACTION: Proposed rule.
SUMMARY: In this document, the
Environmental Protection Agency (EPA)
is proposing maximum contaminant
level goals (MCLGs) for chloroform,
monochloroacetic acid (MCAA) and
trichloroacetic acid (TCAA); National
Primary Drinking Water Regulations
(NPDWRs) which consist of maximum
contaminant levels (MCLs) and
monitoring, reporting, and public
notification requirements for total
trihalomethanes (TTHM—a sum of
chloroform, bromodichIoromethane,
dibromochloromethane, and
bromoform) and haloacetic acids
(HAA5—a sum of mono-, di-, and
trichloroacetic acids and mono- and
dibromoacetic acids); and revisions to
the reduced monitoring requirements
forbromate. This document also
specifies the beet available technologies
(BATs) for the proposed MCLs. EPA is
also proposing additional analytical
methods for the determination of
disinfectants and disinfection
byproducts (DBFs) in drinking water
and proposing to extend approval of
DBF methods for the determination of
additional chemical contaminants. This
set of regulations proposed today is
known as the Stage 2 Disinfectants and
Disinfection Byproducts Rule (Stage 2
DBPR). EPA's objective for the Stage 2
DBPR is to reduce the potential risks of
reproductive and developmental health
effects and cancer associated with
disinfection byproducts (DBFs) by
reducing peak and average levels of
DBFs in drinking water supplies.
The Stage 2 DBPR applies to public
water systems (PWS) that are
community water systems (CWSs) or
nontransient noncommunity water
systems (NTNCWs) that add a primary
or residual disinfectant other than
ultraviolet light or deliver water that has
been treated with a primary or residual
disinfectant other than ultraviolet light.
DATES: The Agency requests comments
on today's proposal. Comments must be
received or post-marked by midnight
November 17, 2003.
ADDRESSES: Comments may be
submitted by mail to: Water Docket,
Environmental Protection Agency, Mail
Code 4101T, 1200 Pennsylvania Ave.,
NW., Washington, DC 20460, Attention
Docket ID No. OW-2002-0043.
Comments may also be submitted
electronically or through hand delivery/
courier by following the detailed
instructions as provided in section I.C.
of the SUPPLEMENTARY INFORMATION
section.
FOR FURTHER INFORMATION CONTACT: For
technical inquiries, contact Tom
Grubbs, Office of Ground Water and
Drinking Water (MC 4607M), U.S.
Environmental Protection Agency, 1200
Pennsylvania Ave., NW., Washington,
DC 20460; telephone (202) 564-5262.
For regulatory inquiries, contact Jennifer
McLain at the same address; telephone
(202) 564-5248. For general information
contact the Safe Drinking Water Hotline,
Telephone (800) 426-4791. The Safe
Drinking Water Hotline is open Monday
through Friday, excluding legal
holidays, from 9 a.m. to 5:30 p.m.
Eastern Time.
SUPPLEMENTARY INFORMATION:
I. General Information
A. Who Is Regulated by This Action?
Entities potentially regulated by the
Stage 2 DBPR are community and
nontransient noncommunity water
systems that add a primary or residual
disinfectant other than ultraviolet light
or deliver water that has been treated
with a primary or residual disinfectant
other than ultraviolet light. Regulated
categories and entities are identified in
the following chart.
Category
State, Local, Tribal, or Federal Governments ....
Examples of regulated entities
Community and nontransient noncommunity water systems that add
infectant other than ultraviolet light or deliver water that has been
residual disinfectant other than ultraviolet light.
Community and nontransient noncommunity water systems that add
infectant other than ultraviolet light or deliver water that has been
residual disinfectant other than ultraviolet light.
a primary or residual dis-
treated with a primary or
a primary or residual dis-
treated with a primary or
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 of which EPA is
now aware that could potentially be
regulated by this action. Other types of
entities not listed in this table could
also be regulated. To determine whether
your facility is regulated by this action,
you should carefully examine the
definition of "public water system" in
§ 141.2 and the section entitled
"coverage" (§141.3) in Title 40 of the
Code of Federal Regulations and
applicability criteria in § 141.600 and
141.620 of today's proposal. If you have
questions regarding the applicability of
the Stage 2 DBPR to a particular entity,
contact one of the persons listed in the
preceding section entitled FOR FURTHER
INFORMATION CONTACT.
B. How Can I Get Copies of This
Document and Other Related
Information?
1. Docket. EPA has established an
official public docket for this action
under Docket ID No. OW-2002-0043.
The official public docket consists of the
documents specifically referenced in
this action, any public comments
received, and other information related
to this action. Although a part of the
official docket, the public docket does
not include Confidential Business
Information (CBI) or other information
whose disclosure is restricted by statute.
The official public docket is the
collection of materials that is available
for public viewing at the Water Docket
in the EPA Docket Center, (EPA/DC)
EPA West, Room B102, 1301
Constitution Ave., NW., Washington,
DC. The EPA Docket Center 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 the Public Reading Room is
(202) 566-1744, and the telephone
number for the Water Docket is (202)
566-2426. For access to docket material,
please call (202) 566-2426 to schedule
an appointment.
2. Electronic Access. You may access
this Federal Register document
electronically through the EPA Internet
under the "Federal Register" listings at
http://nrww.epa.gov/fedrgstr/.
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49549
An electronic version of the public
docket is available through EPA's
electronic public docket and comment
system, EPA Dockets. You may use EPA
Dockets at http://www.epa.gov/edocket/
to submit or view public comments,
access the index listing of the contents
of the official public docket, and to
access those documents in the public
docket that are available electronically.
Once in the system, select "search,"
then key in the appropriate docket
identification number.
Certain types of information will not
be placed in the EPA Dockets.
Information claimed as CBI and other
information whose disclosure is
restricted by statute, which is not
included in the official public docket,
will not be available for public viewing
in EPA's electronic public docket. EPA's
policy is that copyrighted material will
not be placed in EPA's electronic public
docket but will be available only in
printed, paper form in the official public
docket. Although not all docket
materials may be available
electronically, you may still access any
of the publicly available docket
materials through the docket facility
identified in section I.B.I.
For public commenters, it is
important to note that EPA's policy is
that public comments, whether
submitted electronically or in paper,
will be made available for public
viewing in EPA's electronic public
docket as EPA receives them and
without change, unless the comment
contains copyrighted material, CBI, or
other information whose disclosure is
restricted by statute. When EPA
identifies a comment containing
copyrighted material, EPA will provide
a reference to that material in the
version of the comment that is placed in
EPA's electronic public docket. The
entire printed comment, including the
copyrighted material, will be available
in the public docket.
Public comments submitted on
computer disks that are mailed or
delivered to the docket will be
transferred to EPA's electronic public
docket. Public comments that are
mailed or delivered to the Docket will
be scanned and placed in EPA's
electronic public docket. Where
practical, physical objects will be
photographed, and the photograph will
be placed in EPA's electronic public
docket along with a brief description
written by the docket staff.
C. How and to Whom Do J Submit
Comments?
You may submit comments
slectronically, by mail, or through hand
delivery/courier. To ensure proper
receipt by EPA, identify the appropriate
docket identification number in the
subject line on the first page of your
comment. Please ensure that your
comments are submitted within the
specified comment period. Comments
received after the close of the comment
period will be marked "late." EPA is not
required to consider these late
comments.
1. Electronically. If you submit an
electronic comment as prescribed
below, EPA recommends that you
include your name, mailing address,
and an e-mail address or other contact
information in the body of your
comment. Also include this contact
information on the outside of any disk
or CD ROM you submit, and in any
cover letter accompanying the disk or
CD ROM. This ensures that you can be
identified as the submitter of the
comment and allows EPA to contact you
in case EPA cannot read your comment
due to technical difficulties or needs
further information on the substance of
your comment. EPA's policy is that EPA
will not edit your comment, and any
identifying or contact information
provided in the body of a comment will
be included as part of the comment that
is placed in the official public docket,
and made available in EPA's electronic
public docket. If EPA cannot read your
comment due to technical difficulties
and cannot contact you for clarification,
EPA may not be able to consider your
comment.
a. EPA Dockets. Your use of EPA's
electronic public docket to submit
comments to EPA electronically is
EPA's preferred method for receiving
comments. Go directly to EPA Dockets
at http://www.epa.gov/edocket, and
follow the online instructions for
submitting comments. Once in the
system, select "search," and then key in
Docket ID No. OW-2002-0043. The
system is an "anonymous access"
system, which means EPA will not
know your identity, e-mail address, or
other contact information unless you
provide it in the body of your comment.
b. E-mail. Comments may be sent by
electronic mail (e-mail) to OW-
Docket@epa.gov, Attention Docket ID
No. OW-2002-0043. In contrast to
EPA's electronic public docket, EPA's e-
mail system is not an "anonymous
access" system. If you send an e-mail
comment directly to the Docket without
going through EPA's electronic public
docket, EPA's e-mail system
automatically captures your e-mail
address. E-mail addresses that are
automatically captured by EPA's e-mail
system are included as part of the
comment that is placed in the official
public docket, and made available in
EPA's electronic public docket.
c. Disk or CD ROM. You may submit
comments on a disk or CD ROM that
you mail to the mailing address
identified in section I.C.2. These
electronic submissions will be accepted
in WordPerfect or ASCII file format.
Avoid the use of special characters and
any form of encryption.
2. By Mail. Send three copies of your
comments and any enclosures to: Water
Docket, Environmental Protection
Agency, Mail Code 4101T, 1200
Pennsylvania Ave., NW., Washington,
DC 20460, Attention Docket ID No. OW-
2002-0043.
3. By Hand Delivery or Courier.
Deliver your comments to: Water
Docket, EPA Docket Center,
Environmental Protection Agency,
Room B102,1301 Constitution Ave.,
NW., Washington, DC, Attention Docket
ID No. OW-2002-0043. Such deliveries
are only accepted during the Docket's
normal hours of operation as identified
in section I.B.I.
D. What Should I Consider as I Prepare
My Comments for EPA?
You may find the following
suggestions helpful for preparing your
comments:
1. Explain your views as clearly as
possible.
2. Describe any assumptions that you
used.
3. Provide any technical information
and/or data you used that support your
views.
4. If you estimate potential burden or
costs, explain how you arrived at your
estimate.
5. Provide specific examples to
illustrate your concerns.
6. Offer alternatives.
7. Make sure to submit your
comments by the comment period
identified.
8. To ensure proper receipt by EPA,
identify the appropriate docket
identification number in the subject line
on the first page of your response. It
would also be helpful if you provided
the name, date, and Federal Register
citation related to your comments.
Abbreviations Used in This Document
AIPC All Indian Pueblo Council
ALT Alanine aminotransferase
AST Aspartate aminotransferase
ASTM American Society for Testing
and Materials
AWWA American Water Works
Association
AwwaRF American Water Works
Association Research Foundation
BAT Best available technology
BCAA Bromochloroacetic acid
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BDCM Bromodichloromethnne
CWS Community water system
DBAA Dibromoacetic acid
DBCM Dibromochloromethane
DBF Disinfection byproduct
DBPR Disinfectants and Disinfection
Byproducts Rule
DCAA Dichloroacetic acid
DOC Dissolved organic carbon
EA Economic analysis
EC Enhanced coagulation
EDA Ethylenediamine
EDio Maximum likelihood estimate of
a dose producing effects in 10
percent of animals
EPA United States Environmental
Protection Agency
FACA Federal Advisory Committee
Act
FBRR Filter Backwash Recycling Rule
GAG Granular activated carbon
GC/ECD Gas chromatography using
electron capture detection
GWUDI Ground water under the direct
influence of surface water
HAAS Haloacetic acids (five) (sum of
monochloroacetic acid,
dichloroacetic acid, trichloroucotic
acid, monobromoacetic acid, and
dibromoacetic acid)
1C Ion chromatography
ICR Information Collection Request
IC/ICP-MS Ion chromatograph—
coupled to an inductively coupled
plasma mass spectrometer
IDSE Initial distribution system
evaluation
ILSI International Life Sciences
Institute
IESWTR Interim Enhanced Surface
Water Treatment Rule
IPCS International Programme on
Chemical Safety
IRIS Integrated Risk Information
System (EPA)
kWh/yr Kilowatt hours per year
LEDio Lower 95 percent confidence
bound of the maximum likelihood
estimate of the dose producing
effects in 10 percent of animals
LH Luteinizing hormone
LOAEL Lowest observed adverse effect
level
LRAA Locational running annual
average
LT1ESWTR Long Term 1 Enhanced
Surface Water Treatment Rule
LT2ESWTR Long Term 2 Enhanced
Surface Water Treatment Rule
MBAA Monobromoacetic acid
MCAA Monochloroacetic acid
MCL Maximum contaminant level
MCLG Maximum contaminant level
goal
M-DBP Microbial and disinfection
byproducts
mg/L Milligram per liter
MRL Minimum reporting level
MRDL Maximum residual disinfectant
level
MRDLG Maximum residual
disinfectant level goal
MTBE Methyl tertiary butyl ether
mWh Megawatt-hours
NATICH National Air Toxics
Information Clearinghouse
NDIR Nondispersive infrared detection
MDMA N-nitrosodimethylamine
NDWAC National Drinking Water
Advisory Council
NF Nanofiltration
NOAEL No Observed Adverse Effect
Level
NODA Notice of data availability
NPDWR National primary drinking
water regulation
NRWA National Rural Water
Association
NTNCWS Nontransient
noncommunity water system
NTP National Toxicology Program
NTTAA National Technology Transfer
and Advancement Act
ODA o-dianisidine dihydrochloride
OMB Office of Management and
Budget
OSTP Office of Science and
Technology Policy
PAR Population attributable risk
PE Performance evaluation
PWS Public water system
QC Quality control
RAA Running annual average
RFA Regulatory Flexibility Act
RfD Reference dose
RSC Relative source contribution
RSD Relative standard deviation
SAB Science Advisory Board
SAC Selective anion concentration
SBAR Small Business Advisory
Review
SBREFA Small Business Regulatory
Enforcement Fairness Act
SDWA Safe Drinking Water Act, or the
"Act," as amended in 1996
SER Small Entity Representative
SGA Small for gestational age
SUVA Specific ultraviolet absorbance
SWAT Surface Water Analytical Tool
SWTR Surface Water Treatment Rule
TAME Tertiary amyl methyl ether
TCAA Trichloroacetic acid
TCR Total Coliform Rule
THM Trihalomethane
TOG Total organic carbon
TTHM Total trihalomethanes (sum of
four THMs: chloroform,
bromodichloromethane,
dibromochloromethane, and
bromoform)
TWG Technical work group
UMRA Unfunded Mandates Reform
Act
USDOE EIA U.S. Department of
Energy, Energy Information
Administration
UV 254 Ultraviolet absorption at 254
nm
WTP Willingness To Pay
Table of Contents
I. Summary
A. Why is EPA Proposing the Stage 2
DBPR?
B. What Does the Stage 2 DBPR Require?
C, What are the Economic Impacts of the
Stage 2 DBPR?
II. Background
A. What is the Statutory Authority for the
Stage 2 DBPR?
B. What is the Regulatory History of the
Stage 2 DBPR?
C. How were Stakeholders Involved in
Developing the Stage 2 DBPR?
1. Federal Advisory Committee process
2. Other outreach processes
III. Public Health Risk
A. Reproductive and Developmental
Epidemiology
l.Reifef al. 2000
a. Fetal growth
b. Fetal viability
c. Fetal malformations and other
developmental anomalies
2. Bove et al. 2002
a. Fetal growth
b. Fetal viability
c. Fetal malformations
3. Nieuwenhuijsen et al. 2000
4. Additional epidemiology studies
B. Reproductive and Developmental
Toxicology
1. EPA analysis and research
2. Tyl, 2000
a. Developmental defects
b. Whole litter resorption
c. Fetal toxicity
d. Male reproductive effects
3. World Health Organization review of the
reproductive and developmental
toxicology literature (2000)
4. New Studies
C. Conclusions Drawn from the
Reproductive and Developmental Health
Effects Data
D. Cancer Epidemiology
1. Population Attributable Risk analysis
2. New epidemiological cancer studies
a. New bladder cancer studies
b. New colon cancer studies
c. New rectal cancer studies
d. Other cancers
3, Review of the cancer epidemiology
literature (WHO 2000)
E. Cancer and Other Toxicology
1. EPA criteria documents
2. Other byproducts with carcinogenic
potential
a. 3-chloro-4-(dichloromethyl)-5-hydroxy-
2(5H)-furanone) (MX)—multisite cancer
b. N-nitrosodimethylamine (NDMA)—
multisite cancer
3. Other toxicological effects
4. WHO review of the cancer toxicology
literature (2000)
F. Conclusions Drawn from the Cancer
Epidemiology and Toxicology
G. Request for Comment
IV. DBF Occurrence within Distribution
Systems
A. Data Sources
1. Information Collection Rule Data
2. Other Data Sources Used to Support the
Proposal
B. DBFs in Distribution Systems
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49551
1. DBFs above the MCL occur at some
locations in a substantial number of
plants
2. Specific locations in distribution
systems are not protected to MCL levels
3. Stage 1 DBPR maximum residence time
location may not reflect the highest DBF
occurrence levels
C. Request for Comment
V. Discussion of Proposed Stage 2 DBPR
Requirements
A. MCLG for Chloroform
1. What is EPA proposing today?
2. How was this proposal developed?
a. Background
b. Basis of the new chloroform MCLG
i. Mode of action
ii. Metabolism
c. How the MCLG is derived
i. Reference dose
ii. Relative source contribution
iii. Water ingestion and body weight
assumptions
iv. MCLG calculation
v. Other considerations
d. Feasibility of other options
3. Request for comment
B. MCLGs for THMs and HAAs
1. What is EPA proposing today?
2. How was this proposal developed?
a. Trichloroacetic acid
b. Monochloroacetic acid
3. Request for comment
C. Consecutive Systems
1. What is EPA proposing today?
a. Definitions
b. Monitoring
c. Compliance schedules
d. Treatment
e. Violations
f. Public notice and consumer confidence
reports
g. Recordkeeping and reporting
h. State special primacy conditions
2. How was this proposal developed?
3. Request for comment
D. MCLs for TTHM and HAA5
1. What is EPA proposing today?
2. How was this proposal developed?
a. Definition of an LRAA
b. Consideration of regulatory alternatives
c. Basis for the LRAA
d. Basis for phasing LRAA compliance
e. TTHM and HAA5 as Indicators
3. Request for comment
E. Requirements for Peak TTHM and HAAS
Levels
1. What is EPA proposing today?
2. How was this proposal developed?
3. Request for comment
F. BAT for TTHM and HAAS
1. What is EPA proposing today?
2. How was this proposal developed?
a. Basis for the BAT
i. BAT analysis using the Information
Collection Rule treatment studies
ii. BAT analysis using the SWAT
b. Basis for the Consecutive System BAT
3. Request for comment
G. MCL, BAT, and Monitoring for Bromate
1. What is EPA proposing today?
2. How was this proposal developed?
a. Bromate MCL
b. Bromate in hypochlorite solutions
c. Criterion for reduced bromate
monitoring
3. Request for comment
H. Initial Distribution System Evaluation
(IDSE)
1. What is EPA proposing today?
a. Applicability
b. Data collection
i. Standard monitoring program
ii. System specific study
iii. 40/30 certification
c. Implementation
2. How was this proposal developed?
a. Applicability
b. Data collection
c. Implementation
3. Request for comment
a. Applicability
b. Data collection
c. Implementation
I. Monitoring Requirements and
Compliance Determination for Stage 2A
and Stage 2B TTHM and HAAS MCLs
1. What is EPA proposing today?
a. Stage 2A
b. IDSE
c. Stage 2B
i. Subpart H systems serving 10,000 or
more people
ii. Subpart H systems serving 500 to 9,999
people
iii. Subpart H systems serving fewer than
500 people
iv. Ground water systems serving 10,000 or
more people
v. Ground water systems serving fewer
than 10,000 people
vi. Consecutive systems
2. How was this proposal developed?
a. Sampling intervals for quarterly
monitoring
b. Reduced monitoring frequency
c. Different IDSE sampling locations by
disinfectant type
d. Population-based monitoring
requirements for certain consecutive
systems
3. Request for comment
a. Proposed IDSE and Stage 2B monitoring
requirements
b. Plant-based vs. population-based
monitoring requirements
i. Issues with plant-based monitoring
requirements
ii. Approaches to addressing issues with
plant-based monitoring
J. Compliance Schedules
1. What is EPA proposing?
2. How did EPA develop this proposal?
3. Request for comments
K. Public Notice Requirements
1. What is EPA proposing?
2. Request for comments
L. Variances and Exemptions
1. Variances
2. What are the affordable treatment
technologies for small systems?
M. Requirements for Systems to Use
Qualified Operators
N. System Reporting and Recordkeeping
Requirements
1. Confirmation of applicable existing
requirements
2, Summary of additional reporting
requirements
3. Request for comment
O. Analytical Method Requirements
1. What is EPA proposing today?
2. How was this proposal developed?
3. Which new methods are proposed for
approval?
a. EPA Method 327.0 for chlorine dioxide
and chlorite.
b. EPA Method 552.3 for HAAS and
dalapon
c. ASTM D 6581-00 for bromate, chlorite,
and bromide
d. EPA Method 317.0 revision 2 for
bromate, chlorite, and bromide
e. EPA Method 326.0 for bromate, chlorite,
and bromide
f. EPA Method 321.8 for bromate
g. EPA 415.3 for TOC and SUVA (DOC and
4. What additional regulated contaminants
can be monitored by extending approval
of EPA Method 300.1?
5. Which methods in the 20th edition and
2003 On-Line Version of Standard
Methods are proposed for approval?
6. What is the updated citation for EPA
Method 300.1?
7. How is the HAA5 sample holding time
being standardized?
8. How is EPA clarifying which methods
are approved for magnesium
determinations?
9. Which methods can be used to
demonstrate eligibility for reduced
bromate monitoring?
10. Request for comments
P. Laboratory Certification and Approval
1. What is EPA proposing today?
2. What changes are proposed for the PE
acceptance criteria?
3. What minimum reporting limits are
being proposed?
4. What are the requirements for analyzing
IDSE samples?
5. Request for comments
VI. State Implementation
A. State Primacy Requirements for
Implementation Flexibility
B. State Recordkeeping Requirements
C. State Reporting Requirements
D. Interim Primacy
E. IDSE Implementation
F. State Burden
VII. Economic Analysis
A. Regulatory Alternatives Considered by
the Agency
B. Rationale for the Proposed Rule Option
1. Reducing peak exposure
2. Reducing average exposure
C. Benefits of the Proposed Stage 2 DBPR
1. Non-quantifiable health and non-health
related benefits
2. Quantifiable health benefits
3. Benefit sensitivity analyses
D. Costs of the Proposed Stage 2 DBPR
1. National cost estimates
2. Water system costs
3. State costs
4. Non-quantifiable
E. Expected System Treatment Changes
1. Pre-Stage 2 DBPR baseline conditions
2. Predicted technology distributions post-
Stage 2 DBPR
F. Estimated Household Costs of the
Proposed Rule
G. Incremental Costs and Benefits of the
Proposed Stage 2 DBPR
H. Benefits From the Reduction of Co-
Occurring Contaminants
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I. Are there Increased Risks Prom Other
Contaminants?
J. Effects on General Population end
Subpopulation Groups
K. Uncertainties in Baseline, Risk, Benefit,
and Cost Estimates
L. Benefit/Cost Determination for the
Proposed Stage 2 DBPR
M. Request for Comment
VIII. 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 or Low Income
Populations
K. Consultations with the Science
Advisory Board, National Drinking
Water Advisory Council, and the
Secretary of Health and Human Services
L. Plain Language
IX. References
I. Summary
A. Why Is EPA Proposing the Stage 2
DBPfJ?
The Environmental Protection Agency
is committed to ensuring that all public
water systems provide clean and safe
drinking water. Disinfectants are often
an essential element of drinking water
treatment because of the barrier they
provide against harmful waterborne
microbial pathogens. However,
disinfectants react with naturally
occurring organic and inorganic matter
in source water and distribution systems
to form disinfection byproducts (DBFs)
that may pose health risks. The Agency
is proposing the Stage 2 Disinfectants
and Disinfection Byproduct Rule
(DBPR) to reduce potential cancer,
reproductive, and developmental risks
from DBFs.
The Stage 2 DBPR augments the Stage
1 DBPR that was finalized in 1998. The
proposed Stage 2 DBPR focuses on
monitoring and reducing concentrations
of two classes of DBFs: total
tribalomethanes (TTHM) and haloacetic
acids (HAAS). In part, these two groups
of DBFs are used as indicators of the
various byproducts that are present in
disinfected water. This means that
concentrations of TTHM and HAAS are
monitored for compliance, but their
presence in drinking water is
representative of many other DBFs that
may also be present in the water;
likewise, a reduction in TTHM and
HAAS indicates a reduction of total
DBFs.
The Stage 2 DBPR is designed to
reduce the level of exposure from
disinfectants and DBFs without
undermining the control of microbial
pathogens. The Long Term 2 Enhanced
Surface Water Treatment Rule
(LT2ESWTR) will be finalized and
implemented simultaneously with the
Stage 2 DBPR to ensure that drinking
water is microbiologically safe at the
limits set for disinfectants and DBFs.
New information on health effeqts,
occurrence, and treatment has become
available since the Stage 1 DBPR, which
supports the need for die Stage 2 DBPR.
Several reproductive and developmental
studies have recently become available,
and EPA has completed a more
extensive analysis of reproductive and
developmental effects associated with
DBFs since the Stage 1 DBPR. Both
human epidemiology studies and
animal toxicology studies have shown
associations between chlorinated
drinking water and reproductive and
developmental endpoints such as
spontaneous abortion, stillbirth, neural
tube defects, pre-term delivery,
intrauterine growth retardation, and low
birth weight. New epidemiology and
toxicology studies evaluating bladder
and rectal cancers have also increased
the weight of evidence linking these
health effects to DBF exposure. The
large number of people (254 million
Americans) exposed to DBFs and the
identified potential cancer,
reproductive, and developmental risks
played a significant role in EPA's
decision to move forward with
regulatory changes that target lowering
DBF exposures beyond the requirements
of the Stage 1 DBPR.
While the Stage 1 DBPR provided a
major reduction in DBF exposure, new
national survey data suggest that some
customers are receiving drinking water
with elevated, or peak DBF
concentrations even when their
distribution systems are in compliance
with the Stage 1 DBPR. Some of these
peak concentrations can be substantially
greater than the Stage 1 DBPR maximum
contaminant levels (MCLs). The new
survey results also showed that Stage 1
DBPR monitoring sites may not be
representative of peak DBF
concentrations that occur in distribution
systems. In addition, the new
information indicates that cost-effective
technologies including ultraviolet light
(UV) and granular activated carbon
(GAG) may be very effective at lowering
DBF levels. EPA's analysis of this new
information concludes that significant
public health benefits may be achieved
through further cost-effective reduction
of DBFs in distribution systems.
Congress required EPA to promulgate
the Stage 2 DBPR as part of the 1996
Safe Drinking Water Act (SDWA)
Amendments (section 1412(b)(2)(C)).
Today's proposal reflects consensus
recommendations from the Stage 2
Microbial/Disinfection Byproducts (M-
DBP) Federal Advisory Committee (the
Advisory Committee). These
recommendations are set forth in the M-
DBP Agreement in Principle (USEPA
2000g), which can he accessed on the
edocket Web site (www.epa.gov/
edocket}.
After considering the new occurrence
and health effects data and analyses,
EPA has determined that there is an
opportunity to further reduce potential
risks from DBFs. The Stage 2 DBPR
being proposed today presents a cost-
effective, risk targeting approach to
reduce risks from DBFs. The new
requirements provide for more
consistent protection from DBFs across
the entire distribution system and the
reduction of DBF peaks. New risk
targeting provisions require only those
systems with the greatest risk to make
capital improvements. The Stage 2
DBPR, in conjunction with the
LT2ESWTR, will help public water
systems deliver safer water to
Americans with the benefits of
disinfection to control pathogens but
with fewer risks from DBFs.
B. What Does the Stage 2 DBPR Require?
The Stage 2 DBPR applies to
community or nontransient
noncommunity water systems that add
a primary or residual disinfectant other
than ultraviolet light or deliver water
that has been treated with a primary or
residual disinfectant other than
ultraviolet light. The TTHM and HAAS
MCL yalues will remain the same as in
the Stage 1 DBPR, although compliance
calculations will be different. The
proposed Stage 2 DBPR includes new
MCLGs for chloroform,
monochloroacetic acid, and
trichloroacetic acid, but these new
MCLGs do not affect the MCLs for
TTHM or HAAS.
The risk targeting components of the
Stage 2 DBPR will focus the greatest
amount of change where the greatest
amount of risk may exist. The
provisions of the Stage 2 DBPR focus on
identifying and reducing exposure by
reducing DBF peaks in distribution
systems. The first provision, designed to
address significant variations in
exposure, is the Initial Distribution
System Evaluation (IDSE). The purpose
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49553
of the IDSE is to identify Stage 2 DBPR
compliance monitoring sites for
capturing peaks. Because Stage 2 DBPR
compliance will be determined at these
new monitoring sites, distribution
systems that identify elevated
concentrations of TTHM and HAAS will
need to make treatment or process
changes to bring the system into
compliance with the Stage 2 DBPR. By
identifying compliance monitoring sites
with elevated concentrations of TTHM
and HAAS, the IDSE will offer increased
assurance that MCLs are being met
across the distribution system. Both
treatment changes and awareness of
TTHM and HAAS levels resulting from
the IDSE will allow systems to better
control for distribution system peaks.
The IDSE is designed to offer
flexibility to public water systems. The
IDSE requires TTHM and HAAS
monitoring for one year on a regular
schedule that is determined by source
water type and system size. Systems
have the option of performing a site-
specific study based on historical data,
water distribution system models, or
other data; and waivers are available
under certain circumstances. The
proposed IDSE requirements are
discussed in sections V.H., V.I., and V.J.
of this preamble and in subpart U of the
proposed rule.
The second provision of the Stage 2
DBPR, which is designed to address
variations in temporal and spatial
exposure, is the new compliance
calculation of the MCLs. The Stage 1
DBPR running annual average (RAA)
calculation allows some locations
within a distribution system to have
higher DBF annual averages than others
as long as the system-wide average is
below the MCL. The Stage 2 DBPR will
base compliance on a locational running
annual average (LRAA) calculation
where the annual average at each
sampling location in the distribution
system will be used to determine
compliance with the MCLs. The LRAA
will reduce exposures to peak DBP
concentrations by ensuring that each
monitoring site is in compliance with
the MCLs as an annual average, and it
will provide all customers drinking
water that more consistently meets the
MCLs.
EPA is proposing that systems comply
with the Stage 2 DBPR MCLs in two
phases, designated as Stage 2A and
Stage 2B. In Stage 2A, beginning three
years after the rule is final, all systems
must comply with MCLs of 0.120 mg/L
for TTHM and 0.100 mg/L for HAAS as
LRAAs at Stage 1 DBPR sampling sites,
in addition to continuing to comply
with the Stage 1 DBPR MCLs of 0.080
mg/L and 0.060 mg/L as RAAs for
TTHM and HAAS, respectively. In Stage
2B, systems must comply with MCLs of
0.080 mg/L and 0.060 mg/L as LRAAs
for TTHM and HAAS, respectively,
based on sampling sites identified
through the IDSE. A more detailed
discussion of the proposed Stage 2
DBPR MCL requirements can be found
in sections V.D., V.I., and V.). of this
preamble and in § 141.64(b)(2) and (3),
and § 141.136, and subpart V of the rule
language.
The IDSE and LRAA calculation will
lead to overall reductions in DBP
concentrations and reduce short term
exposures to high DBP concentrations,
but even with this strengthened
approach to regulating DBFs it will be
possible for individual DBP samples to
exceed the MCLs when systems are in
compliance with the Stage 2 DBPR. The
Stage 2 DBPR requires systems that
experience significant excursions to
evaluate distribution system operational
practices and identify opportunities to
reduce DBP concentrations in the
distribution system. This provision will
curtail peaks and reduce exposure to
high DBP levels. Significant excursions
are discussed in greater detail in section
V.E.
The Stage 2 DBPR also contains
provisions for regulating consecutive
systems, defined in the Stage 2 DBPR as
public water systems that buy or
otherwise receive some or all of their
finished water from another public
water system on a regular basis.
Uniform regulation of consecutive
systems provided by the Stage 2 DBPR
will ensure that consecutive systems
deliver drinking water that meets
applicable DBP standards. More
information on regulation of
consecutive systems can be found in
sections V.C., V.H., V.I. and V.}.
Today's document proposes plant-
based monitoring requirements for non-
consecutive systems and certain
consecutive systems. Plant-based
monitoring means that the number of
compliance monitoring locations within
a distribution system is based on the
number of plants, population served,
and type of source water used by the
distribution system. EPA is proposing
population-based monitoring for
consecutive systems that buy all their
finished water from other public water
systems. EPA is also requesting
comment on whether this approach
should be extended to all systems
covered by today's rule. Under a
population-based monitoring structure,
the number of compliance monitoring
locations is based only on the
population served and source water
type. Section V.I. describes population-
based monitoring and how it might
affect systems complying with this rule.
C. What Are the Economic Impacts of
the Stage 2 DBPR?
EPA quantified the potential benefits
of the Stage 2 DBPR by estimating the
reduction in bladder cancer cases that
may result from the decrease in average
DBP concentrations in disinfected
water. Estimated reductions in DBF-
related bladder cancers (including both
fatal and non-fatal cases) result in
annualized benefits ranging from $0 to
$986 million (using a three percent
discount rate), depending on the risk
level assumed.
There may also be a number of
important nonquantifiable benefits
associated with reducing DBFs in
drinking water, the primary ones being
reduced potential risk of adverse
reproductive and developmental effects
including miscarriage, stillbirth, neural
tube defects, heart defects, and cleft
palate. Although a number of studies
have found an association between
reproductive and developmental
endpoints and short-term exposure to
elevated DBP levels, a causal link has
not yet been established and
information is not yet available to
quantify potential effects. As a result,
the Agency has not included an estimate
of the potential benefits from reducing
reproductive and developmental risks in
its primary economic impact analysis of
the Stage 2 DBPR. However, an
illustrative calculation of potential fetal
loss risk is discussed in Section VII and
presented in more detail in the
Economic Analysis (USEPA 2003iJ to
illustrate the benefits that could be
associated with this rule. Reduction in
other cancers potentially associated
with DBP exposure represent additional
unquantified health benefits.
EPA estimates the total annualized
costs of the Stage 2 DBPR to be $54 to
$64 million. This estimate includes
costs associated with treatment changes,
the Initial Distribution System
Evaluation, changes in compliance
monitoring, and rule implementation
activities for both public water systems
and States. EPA estimates that
approximately 2.8 percent of all plants
will need to convert to chloramines or
add advanced treatment to comply with
the Stage 2 DBPR.
Table 1-1 presents the estimated
quantified and unquantified benefits of
the Stage 2 DBPR and the estimated
costs. Analyses of unquantified benefits
suggest that the total benefits associated
with the Stage 2 DBPR might be much
greater than these estimates. By
targeting risks and building on the solid
foundation of the Stage 1 DBPR, the
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Stage 2 DBPR will deliver cost-effective reductions in DBF levels and associated
potential public health risks.
TABLE M.—COSTS AND BENEFITS OF THE STAGE 2 DBPR BASED ON ANNUALIZATION DISCOUNT RATE OF 3%
Costs
$54-64 M
Benefits
$0-986 M
Unqualified benefits
and rectal cancer, improved taste and odor of drinking water, control of contaminants that may be
regulated in the future.
II. Background
A combination of factors have
influenced the development of the
proposed Stage 2 DBPR. These include
the initial 1992-1994 Microbial and
Disinfection Byproduct (M-DBP)
stakeholder deliberations and EPA's
Stage 1 DBPR proposal; the 1996 Safe
Drinking Water Act (SDWA)
Amendments; the 1996 Information
Collection Rule; the 1998 Stage 1 DBPR;
other new data, research, and analysis
on disinfection byproduct (DBF)
occurrence, treatment, and health effects
since the Stage 1 DBPR; and the Stage
2 DBPR Microbial and Disinfection
Byproducts Federal Advisory
Committee. The following shows how
EPA arrived at this proposal for
regulating disinfection byproducts.
A, What Is the Statutory Authority for
the Stage 2 DBPR?
Jhe SDWA, as amended in 1996,
authorizes EPA to promulgate a national
primary drinking water regulation
(NPDWR) and publish a maximum
contaminant level goal (MCLG) for
contaminants the Administrator
determines "may have an adverse effect
on the health of persons," is "known to
occur or there is a substantial likelihood
that the contaminant will occur in
public water systems with a frequency
and at levels of public health concern,"
and for which "in the sole judgement of
the Administrator, regulation of such
contaminant presents a meaningful
opportunity for health risk reduction for
persons served by public water
systems" (SDWA section 1412(b}(l)(A)).
MCLGs are non-enforceable health goals
set at a level at which "no known or
anticipated adverse effects on the health
of persons occur and which allows an
adequate margin of safety". These
health goals are published at the same
time as the NPDWR (sections 1412(b)(4)
and 1412(a)(3)).
The Agency may also consider
additional health risks from other
contaminants and establish an MCL "at
a level other than the feasible level, if
the technology, treatment techniques,
and other means used to determine the
feasible level would result in an
increase in the health risk from drinking
water by—(i) increasing the
concentration of other contaminants in
drinking water; or (ii) interfering with
the efficacy of drinking water treatment
techniques or processes that are used to
comply with other national primary
drinking water regulations" (section
1412(b)(5)(A)). When establishing an
MCL or treatment technique under this
authority, "the level or levels of
treatment techniques shall minimize the
overall risk of adverse health effects by
balancing the risk from the contaminant
and the risk from other contaminants
the concentrations of which may be
affected by the use of a treatment
technique or process that would be
employed to attain the MCL or levels"
(section 1412(b)(5)(B)).
Finally, section 1412(b)(2)(C) of the
Act requires EPA to promulgate a Stage
2 DBPR 18 months after promulgation of
the Long Term 1 Enhanced Surface
Water Treatment Rule (LTlESWTR).
Consistent with statutory requirements
for risk balancing (section
1412(b)(5)(B)), EPA will finalize the
LT2ESWTR concurrently with the Stage
2 DBPR to ensure simultaneous
protection from microbial and DBP
risks.
B. What Is the Regulatory History of the
Stage 2 DBPR?
The first rule to regulate DBPs was
promulgated on November 29, 1979.
The Total Trihalomethanes Rule (44 FR
68624) (USEPA 1979} set an MCL of
0.10 mg/L for total trihalomethanes
(TTHMs). Compliance was based on the
running annual average (RAA) of
quarterly averages of all samples
collected throughout the distribution
system. This TTHM standard applied
only to community water systems using
surface water and/or ground water that
served at least 10,000 people and added
a disinfectant to the drinking water
during any part of the treatment process.
Under the Surface Water Treatment
Rule (SWTR) (54 FR 27486, June 29,
1989) (USEPA 1989a), EPA set MCLGs
of zero for Giardia lamblia, viruses, and
LegioneUa; and promulgated NPDWRs
for all public water systems using
surface water sources or ground water
sources under the direct influence of
surface water. The SWTR includes
treatment technique requirements for
filtered and unfiltered systems that are
intended to protect against the adverse
health effects of exposure to Giardia
lamblia, viruses, and LegioneUa, as well
as other pathogenic organisms.
EPA also promulgated the Total
Coliform Rule (TCR) on June 29, 1989
(54 FR 27544)(USEPA 1989b) to provide
protection from microbial
contamination in distribution systems of
all types of public water supplies. The
TCR established an MCLG of zero for
total and fecal coliform bacteria, and an
MCL based on the percentage of positive
samples collected during a compliance
period. Under the TCR, no more than 5
percent of distribution system samples
collected in any month may contain
coliform bacteria.
Together, the SWTR and the TCR
were intended to address risks
associated with microbial pathogens
that might be found in source waters or
associated with distribution systems.
However, while reducing exposure to
pathogenic organisms, the SWTR also
increased the use of disinfectants in
some public water systems and, as a
result, exposure to DBPs in those
systems.
In 1992, prompted by concerns about
health risk tradeoffs between
disinfection byproducts and microbial
pathogens, EPA initiated a negotiated
rulemaking with a wide range of
stakeholders. The negotiators included
representatives of State and local health
and regulatory agencies, public water
systems, elected officials, consumer
groups, and environmental groups. The
Regulatory Negotiating Committee met
from November 1992 through June 1993.
Following months of intensive
discussions and technical analyses, the
Regulatory Negotiating Committee
recommended the development of three
sets of rules: an Information Collection
Rule, a two-staged approach for
regulating DBPs, and an "interim"
Enhanced Surface Water Treatment Rule
(IESWTR) to be followed by a "final"
Enhanced Surface Water Treatment Rule
(USEPA 1996a, USEPA 1998c, USEPA
1998d). EPA took the first step towards
implementing this strategy by proposing
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49555
the Stage 1 DBPR and IESWTR in 1994.
Congress affirmed the phased microbial
and disinfection byproduct rulemaking
strategy in the 1996 SDWA
Amendments by requiring that EPA
develop these three sets of rules on a
specific schedule that stipulates
simultaneous promulgation of
requirements governing microbial
protection and DBFs.
In March 1997, the Agency
established the Microbial and
Disinfection Byproduct (M-DBP)
Advisory Committee under the Federal
Advisory Committee Act (FACA) to
collect, share, and analyze new
information and data available since the
1994 proposals of the Stage 1 DBPR and
the IESWTR, as well as to build
consensus on the regulatory
implications of the new information.
The Advisory Committee consisted of
17 members representing EPA, State and
local public health and regulatory
agencies, local elected officials, drinking
water suppliers, chemical and
equipment manufacturers, and public
interest groups. The Advisory
Committee met five times in March
through July 1997 to discuss issues
related to the IESWTR and the Stage 1
DBPR. The Advisory Committee reached
consensus on a number of major issues
that were incorporated into the Stage 1
DBPR and the IESWTR.
The Stage 1 DBPR and IESWTR,
finalized in December 1998, were the
first rules to be promulgated under the
1996 SDWA Amendments (USEPA
1998c and 1998d). The Stage 1 DBPR
applies to all community and
nontransient noncommunity water
systems that add a chemical disinfectant
to water. Thexule established maximum
residual disinfectant level goals
(MRDLGs) and enforceable maximum
residual disinfectant level (MRDL)
standards for three chemical
disinfectants—chlorine, chloramine,
and chlorine dioxide; maximum
contaminant level goals (MCLGs) for
three THMs, two haloacetic acids
^HAAs), bromate, and chlorite; and
enforceable maximum contaminant
level (MCL) standards for TTHM, five
lialoacetic acids (HAAS), chlorite, and
bromate calculated as running annual
averages (RAAs). The Stage 1 DBPR uses
TTHMs and HAAS as indicators of the
various DBPs that are present in
disinfected water. Under the Stage 1
DBPR, water systems that use surface
water or ground water under the direct
influence of surface water and use
conventional filtration treatment are
required to remove specified
percentages of organic materials,
measured as total organic carbon (TOC),
:hat may react with disinfectants to form
DBPs. Removal is achieved through
enhanced coagulation or enhanced
softening, unless a system meets
alternative compliance criteria.
EPA finalized the IESWTR at the same
time as the Stage 1 DBPR to ensure
simultaneous compliance and address
risk tradeoff issues. The IESWTR
applies to all water systems that use
surface water or ground water under the
direct influence of surface water that
serve at least 10,000 people. The
purpose of the IESWTR is to improve
control of microbial pathogens in
drinking water, specifically the
protozoan Cryptosporidium.
The Filter Backwash Recycle Rule
(FBRR) and the Long Term 1 Enhanced
Surface Water Treatment Rule
(LT1ESWTR) round out the first group
of regulations balancing microbial and
DBF risks. EPA promulgated the FBRR
in 2001 (USEPA 2001c) and the
LT1ESWTR in 2002 (USEPA 2002b) to
increase protection of finished drinking
water supplies from contamination by
Cryptosporidium and other microbial
pathogens. The LTlESWTR extends
protection against Cryptosporidium and
other disease-causing microbes to water
systems that use surface water or ground
water under the direct influence of
surface water that serve fewer than
10,000 people. While the Ground Water
Rule, proposed in May 2000, (USEPA
2000h) will add significant protection
from pathogens in vulnerable ground
water systems, it does not pose as many
risk-risk tradeoff considerations as the
surface water rules because only a small
percentage of ground water systems
subject to the Stage 2 DBPR have high
DBF levels.
EPA reconvened the Advisory
Committee in March 1999 to develop
recommendations on issues pertaining
to the Stage 2 DBPR and LT2ESWTR.
The Advisory Committee collected,
developed, and evaluated new
information that became available after
the Stage 1 DBPR was published. The
Information Collection Rule provided
new data on DBF exposure, and control;
it also included new data on occurrence
and treatment of pathogens. The
unprecedented amount of information
collected under the Information
Collection Rule was supplemented by a
survey conducted by the National Rural
Water Association, data provided by
various States, the Water Utility
Database (which contains data collected
by the American Water Works
Association), and Information
Collection Rule Supplemental Surveys.
This large body of data allowed the
Advisory Committee to reach new
conclusions regarding DBF exposure
and new treatment options.
After analyzing the data, the Advisory
Committee reached three significant
conclusions that led the Advisory
Committee to recommending further
control of DBPs in public water systems.
The data from the Information
Collection Rule show that the RAA
compliance calculation allows elevated
DBF levels to regularly occur at some
locations in the system when the overall
average at all locations is below the
MCL. Customers served at those
sampling locations that regularly exceed
the MCLs are experiencing higher
exposure compared to customers served
at locations that consistently meet the
MCLs.
Second, the new data demonstrated
how single samples can be substantially
above the MCLs. The new information
showed that it is possible for customers
to receive drinking water with
concentrations of DBPs up to 75% above
the MCLs even when their water system
is in compliance with the Stage 1 DBPR.
Studies have shown that DBF exposure
during short, critical time windows may
adversely impact reproductive and
developmental health.
Third, data from the Information
Collection Rule revealed that the highest
TTHM and HAAS levels are not always
located at the maximum residence time
monitoring sites specified by the Stage
1 DBPR. These sites were required for
monitoring by the Stage 1 DBPR because
previous data suggested that water in
the distribution system for the
maximum residence time would have
the highest TTHM levels. The fact that
the locations with the highest DBF
levels varied in different public water
systems indicates that the Stage 1 DBPR
monitoring sites may not be
representative of the high DBF
concentrations that actually exist in
distribution systems, and additional
monitoring is needed to identify
distribution system locations with
elevated DBF levels. This information
encouraged the Advisory Committee to
recommend additional measures to
identify locations with high LRAAs.
Section IV provides a complete
discussion of the new occurrence data.
The analysis of the new data also
indicates that certain technologies are
effective at reducing DBF
concentrations. Bench- and pilot-scale
studies for granular activated carbon
(GAC) and membrane technologies
required by the Information Collection
Rule provided information on the
effectiveness of the two technologies.
Other studies found UV light to be
highly effective for inactivating
Cryptosporidium and Giardia at low
doses without promoting the formation
of DBPs (Malley et al. 1996; Zheng et al.
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1999). This new treatment information
added to the treatment options available
to utilities for controlling DBFs beyond
the requirements of the Stage 1 DBPR.
New data on the health effects of
DBFs also influenced the Advisory
Committee's recommendation to further
regulate DBFs. Although bladder cancer
risks were the focus of the Stage 1 M-
DBF negotiations, potential
reproductive and developmental health
effects were central to the Stage 2 M-
DBP Advisory Committee discussions.
Recent human epidemiology studies
and animal toxicology studies have both
shown associations between chlorinated
drinking water and reproductive and
developmental health effects such as
spontaneous abortion, stillbirth, neural
tube defects, pre-term delivery,
intrauterine growth retardation, and low
birth weight. A critical review of the
epidemiology literature pertaining to
reproductive and developmental effects
of exposure to DBFs completed in 2000
(Reif et al. 2000) concluded that "the
weight of evidence from the
epidemlological studies also suggests
that they [DBPs] are likely to be
reproductive toxicants in humans under
appropriate exposure conditions * * *
and that measures aimed at reducing the
concentrations of byproducts could
have a positive impact on public
health."
While there has been substantial
research to date, the Advisory
Committee recognized that significant
uncertainty remains regarding the risk
associated with DBPs in drinking water.
The Advisory Committee carefully
considered the analyses described
previously, as well as costs and
potential impacts on public water
systems, and concluded that a targeted
protective public health approach
should be taken to address exposure to
DBPs beyond the requirements of the
Stage 1 DBPR. After reaching this
conclusion, the Advisory Committee
developed an Agreement in Principle
(USEPA 2000g) that laid out their
recommendations on how to further
control DBPs in public water systems.
In the Agreement in Principle, the
Advisory Committee recommended
maintaining the MCLs for TTHM and
HAAS at 0.080 mg/L and 0.060 mg/L
respectively, but changing the
compliance calculation in two phases to
facilitate systems moving from the
running annual average (RAA)
calculation to a locational running
annual average (LRAA) calculation. In
the first phase, systems would continue
to comply with the Stage 1 DBPR MCLs
as RAAs and, at the same time, comply
with MCLs of 0.120 mg/L for TTHM and
0.100 mg/L for HAAS calculated as
LRAAs. RAA calculations average all
samples collected within a distribution
system over a one-year period, but
LRAA calculations average all samples
taken at each individual sampling
location in a distribution system during
a one-year period. Systems would also
carry out an Initial Distribution System
Evaluation (IDSE) to select new
compliance monitoring sites that more
accurately reflect higher TTHM and
HAAS levels occurring in the
distribution system. The second phase
of compliance would require MCLs of
0.080 mg/L for TTHM and 0.060 mg/L
for HAAS calculated as LRAAs at
individual monitoring sites identified
through the IDSE.
The Agreement in Principle also
provided recommendations for
simultaneous compliance with the
LT2ESWTR so that the reduction of
potential health hazards of DBPs does
not compromise microbial protection.
The recommendations for the
LT2ESWTR included treatment
requirements for Cryptosporidmm based
on the results of source water
monitoring, a toolbox of options for
providing additional treatment at high
risk facilities, use of microbial
indicators to reduce Cryptosporidium
monitoring burden on small systems,
and future monitoring to determine if
source water quality remains constant
after completion of initial monitoring.
The Agreement also encouraged EPA to
develop guidance and criteria to
facilitate the use of UV light for
compliance with drinking water
disinfection requirements. The complete
text of the Agreement in Principle
(USEPA 2000g) can be found at the
edocket Web site (http://www.epa.gov/
edocket).
After extensive analysis and
investigation of available data and rule
options considered by the Advisory
Committee, EPA is proposing a Stage 2
DBPR control strategy that is consistent
with the key elements of the Agreement
in Principle signed in September 2000
by the participants in the Stage 2 M-
DBP Advisory Committee. EPA
determined that the risk-targeting
measures recommended in the
Agreement in Principle will require
only those systems with the greatest risk
to make treatment and operational
changes and will maintain simultaneous
protection from the potential health
hazards of DBPs and microbial
contaminants. EPA has carefully
evaluated and expanded upon the
recommendations of the Advisory
Committee to more fully develop
today's proposal. EPA also made
simplifications where possible to
minimize complications for public
water systems as they transition to
compliance with the Stage 2 DBPR
while expanding public health
protection. The proposed requirements
of the Stage 2 DBPR are described in
detail in section V of this preamble.
C. How Were Stakeholders Involved in
Developing the Stage 2 DBPR?
1. Federal Advisory Committee Process
The Stage 2 M-DBP Advisory
Committee consisted of 21
organizational members representing
EPA, State and local public health and
regulatory agencies, local elected
officials, Native American Tribes, large
and small drinking water suppliers,
chemical and equipment manufacturers,
environmental groups, and other
stakeholders. Technical support for the
Advisory Committee's discussions was
provided by a technical working group
established by the Advisory Committee.
The Advisory Committee held ten
meetings to discuss issues pertaining to
the Stage 2 DBPR and LT2ESWTR from
September 1999 to July 2000 which
were open to the public. There was also
an opportunity for public comment at
each meeting.
In September 2000, the Advisory
Committee signed the Agreement in
Principle, a full statement of the
consensus recommendations of the
group. The agreement was published by
EPA in a December 29, 2000 Federal
Register notice (65 FR 83015), together
with the list of committee members and
their organizations. The Agreement is
divided into Parts A and B. The
recommendations in each part stand
alone and are independent of one
another. The entire Advisory Committee
reached consensus on Part A, which
contains provisions that directly apply
to the proposed Stage 2 DBPR and
LT2ESWTR. The full Advisory
Committee, with the exception of the
National Rural Water Association
(NRWA), also agreed to Part B, which
has recommendations for future
activities by EPA in the areas of
distribution systems and microbial
water quality criteria.
2. Other Outreach Processes
EPA received valuable input from
small system operators as part of an
Agency outreach initiative under the
Regulatory Flexibility Act (RFA). EPA
also conducted outreach conference
calls to solicit feedback and information
from Small Entity Representatives
(SERs) on issues related to Stage 2 DBPR
impacts on small systems. The Agency
consulted with State, local, and Tribal
governments on the proposed Stage 2
DBPR. Section VIII includes a complete
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description of the many stakeholder
activities which contributed to the
development of the Stage 2 DBPR.
The Agency held two meetings to
discuss consecutive system issues
relevant to the proposal (February 22-
23, 2001 in Denver, CO and March 28,
2001 in Washington, DC).
Representatives from States, EPA
Regions, and public water systems
participated in the discussions. EPA
also briefed the National Drinking Water
Advisory Committee at their November
2001 meeting on consecutive system
issues associated with the rule to
receive input on the implementation
strategy selected. This Advisory
Committee generally supported EPA's
approach. Section V describes EPA's
analysis of consecutive system issues,
comments and input received during
these sessions, and how the proposed
requirements will apply to consecutive
systems. EPA also consulted with the
Science Advisory Board in December
2001 on the requirements of the Stage 2
DBPR.
Finally, EPA posted a pre-proposal
draft of the Stage 2 DBPR preamble and
regulatory language on an EPA Internet
site (http://www.epa.gov/safewater/
mdbp/st2dis.html) on October 17, 2001.
This public review period allowed
readers to comment on the Stage 2
DBPR's consistency with the Agreement
in Principle of the Stage 2 M-DBP
Advisory Committee. EPA received
important suggestions on this pre-
proposal draft from 14 commenters
which included public water systems,
State governments, laboratories, and
other stakeholders. While EPA will not
formally respond to these comments,
EPA has carefully considered them in
developing today's proposal.
III. Public Health Risk
Chlorine has been widely used as a
chemical disinfectant, serving as a
principal barrier to microbial
contaminants in drinking water.
However, the microbial risk reduction
attributes of chlorination have been
increasingly scrutinized due to concerns
about potential increased health risks
from exposure to disinfection
byproducts, which are formed when
certain disinfectants interact with
organic and inorganic material in source
waters. Since the discovery of
chlorination byproducts in drinking
water in 1974, numerous toxicological
studies have shown several DBPs (e.g.,
bromodichloromethane, bromoform,
chloroform, dichloroacetic acid,
trichloroacetic acid and bromate) to be
carcinogenic in laboratory animals.
These findings of carcinogenicity
influenced EPA to promulgate the
TTHM Rule in 1979 and the Stage 1
DBPR in 1998. The Stage 1 DBPR
primarily addressed possible
carcinogenic effects (e.g., bladder, colon
and rectal cancers} reported in both
human epidemiology and laboratory
animal studies. Since the Stage 1 DBPR,
new health studies continue to support
an association between bladder, colon
and rectal cancers from long-term
exposure to chlorinated surface water.
In addition to cancer effects, recent
studies have reported associations
between use of chlorinated drinking
water and a number of reproductive and
developmental endpoints including
spontaneous abortion, still birth, neural
tube defect, pre-term delivery, low birth
weight and intrauterine growth
retardation (small for gestational age).
Short-term, high-dose animal screening
studies on individual byproducts (e.g.,
bromodichloromethane (BDCM), and
certain haloacetic acids) have also
reported adverse reproductive and
developmental effects (e.g., whole litter
resorption, reduced fetal body weight}
that are similar to those reported in the
human epidemiology studies. This
section discusses the new studies that
have become available since
promulgation of the Stage 1 DBPR and
how they contribute to the weight of
evidence for an association between
health effects and exposure to
chlorinated surface water.
While the Stage 1 DBPR was targeted
primarily at reducing long-term
exposures to elevated levels of DBPs to
address chronic health risks from
cancer, the Stage 2 DBPR targets
reducing short-term exposures to
address potential reproductive and
developmental health risks and cancer
risks.
Based on the weight of evidence from
both the human epidemiology and
animal toxicology data on cancer and
reproductive and developmental health
effects and consideration of the large
number of people exposed to
chlorinated byproducts in drinking
water (approximately 254 million), EPA
concludes that: (1) Current reproductive
and developmental health effects data
support a hazard concern, (2) new
cancer data strengthens the evidence of
an association of chlorinated water with
bladder cancer and suggests an
association for colon and rectal cancers,
and (3) the combined health data
warrant regulatory action beyond the
Stage 1 DBPR.
A. Reproductive and Developmental
Epidemiology
The following section briefly
discusses reproductive and
developmental epidemiology
information EPA analyzed, some
conclusions of these studies and reports,
and implications for the Stage 2 DBPR.
Further discussion of the implications
and EPA's conclusions can be found in
the Stage 2 Economic Analysis (USEPA
2003i).
EPA has evaluated recently published
epidemiological studies examining the
relationship between exposure to
contaminants in chlorinated surface
water and adverse reproductive and
developmental outcomes. EPA also
considered critical reviews of the
epidemiological literature by Reif et al.
(2000), Bove et al (2002), and
Nieuwenhuijsen et al. (2000). Based on
these evaluations, EPA believes that the
reproductive and developmental
epidemiology data contribute to the
weight of evidence on the potential
health risks from exposure to
chlorinated drinking water. Although
the data are not suitable for a
quantitative risk assessment at this time,
due in part to inconsistencies in the
findings, they do suggest that exposure
to DBPs is a potential reproductive and
developmental health hazard.
1. Reif et al. 2000
Reif et al. (2000) completed a critical
review of the epidemiology literature
pertaining to reproductive and
developmental effects of exposure to
disinfection byproducts in drinking
water as a report to Health Canada. The
review focused on 16 peer-reviewed
scientific manuscripts and published
reports and evaluated associations
between DBF exposure and outcomes
grouped as effects on: (1) Fetal growth—
low birth weight (<2500g); very low
birth weight (<1500g); preterm delivery
(<37 weeks of gestation) and
intrauterine growth retardation (or small
for gestational age); (2) fetal viability
(spontaneous abortion and stillbirth)
and (3) fetal malformations (all
malformations, oral cleft defects, major
cardiac defects, neural tube defects, and
chromosomal abnormalities).
a. Fetal growth. Reif et al. (2000)
found inconsistent epidemiological
evidence for an association between
DBPs and fetal growth. Some studies
found weak but statistically significant
associations (Gallagher et al. 1998; Bove
etal 1992 and 1995), while two studies
found no association (Dodds et al. 1999;
and Savitz et al. 1995) with fetal growth.
b. Fetal viability. Reif et al. 2000's
review of the literature found
inconsistencies in the epidemiological
evidence for the association between
DBF exposure and fetal viability. For
instance, the study by Waller et al. 1998
found an apparent dose-dependent
increase in rates of spontaneous
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abortions associated with TTHMs in
California. On the other hand, Savitz et
al (1995) found little evidence of an
association using either the
concentration of TTHM £81 ug/L or a
dose estimate based on the amount of
tap water consumed. An increased risk
of stillbirth was reported for women in
Nova Scotia by Dodds et al. 1999, but
in New Jersey, Bove et al (1992,1995)
found little evidence of an association
with TTHM at 80 ug/L, but did report
a weak association between stillbirth
and use of surface water systems.
Aschengrau et al. (1993) found an
association between stillbirth and the
use of a chlorinated vs. chloraminated
surface water supply, but not for
exposure to surface water.
c. Fetal malformations and other
developmental anomalies. Reif et al.
(2000) considered the data for
congenital anomalies to be inconsistent
across the six studies that have explored
these outcomes. For example, two of the
four studies on neural tube defects
(Bove etal. 1995; Magnus era/. 1999)
reported significant excess risks, but the
remaining two studies (Dodds et al.
1999; Klotz and Pyrch et al. 1999) did
not. These studies found lower risks or
no evidence of an association with
TTHM. However, those studies were
conducted in locations with either very
low or high concentrations of DBFs
which may have limited the contrast in
exposures, thereby reducing the ability
to detect increased risks. An assessment
of congenital anomalies is also difficult
due to the relatively small number of
cases available for evaluation.
Overall, Reif et al. (2000) conclude
that the weight of evidence from the
epidemiological studies suggest that
"DBFs are likely to be reproductive
toxicants in humans under appropriate
exposure conditions." Reif et al.
comment that data from animal studies
of individual DBFs provide biological
plausibility for the effects observed in
epidemiological studies. Although the
authors recognize that the "data are
primarily at the stage of hazard
identification," they conclude that
"measures aimed at reducing the
concentrations of byproducts could
have a positive impact on public
health."
2. Bove et al. 2002
Bove et al. (2002) conducted a
qualitative review of 14 epidemiological
studies that evaluated possible
developmental and reproductive
endpoints associated with exposure to
chlorination byproducts in drinking
water. Similar to Reif et al., Bove et ai.
evaluated associations between DBF
exposure and outcomes grouped as
effects on (1) fetal growth—small for
gestational age fSGA) as defined in each
study (usually defined as the fifth or
tenth percentile weight by gestational
week of birth); (2) fetal viability-
spontaneous abortion and stillbirth; and
(3) fetal malformations (neural tube
defects, oral clefts, and cardiac defects).
a. Fetal growth. Bove et al. found that,
although the studies that evaluated SGA
had several limitations, three studies
out of eight (Kramer et al. 1992, Bove et
al. 1995, and Gallagher et al. 1998)
"provided moderate evidence for a
causal relationship between a narrow
definition of SGA* * * and TTHM
levels that could be found currently in
some U.S. public water systems." They
also concluded that the study with the
best exposure assessment found the
strongest association between SGA and
TTHM exposure (Gallagher et al. 1998).
One study found a very weak
association (Dodds etal. 1999) and the
other four did not observe an
association (Yang etal 2000, Kanitz et
al. 1996, Kallen et al. 2000, and Jaakkola
et al. 2001).
b. Fetal viability. Bove et al. evaluated
three studies on spontaneous abortion
and three studies on stillbirth. Again,
Bove et al. found that the study
employing the best methods found the
strongest association between TTHM
exposure and spontaneous abortions
(Waller et a!. 1998). The other two
studies (Savitz et al. 1995 and
Aschengrau et al. 1989) found weak
associations. Two of the studies
investigating stillbirths found an
association between stillbirths and
chlorinated surface water (Dodds et al.
2001 and Aschengrau et al. 1993). The
third study (Bove et al. 1995) found no
association, however this study did not
evaluate individual THM levels or cause
of death information.
c. Fetal malformations. Bove et al.
evaluated seven studies that
investigated the relationship between
birth defects and DBF exposure. This
evaluation found "consistency among
these studies in the findings for neural
tube defects and oral cleft defects, but
not for cardiac defects. Associations
were found for neural tube defects in all
three studies that examined neural tube
defects. These studies also evaluated
levels of THM exposure (Bove et al.
1995; Dodds et al. 1999; Klotz et al.
1999)." Two studies evaluated oral cleft
defects and levels of THMs; one found
an association with TTHM (Bove et al.
1995) and the other found an
association with chloroform (Dodds et
al. 2001). A third study that did not
evaluate THM levels did not identify an
association with oral cleft defects
(Jaakkola et al. 2001). Bove et al 1995
found an association between cardiac
defects and TTHM, but Dodds et al.
1999, 2001 and Shaw et al 1991 did
not. An association between
chlorination and urinary tract defects
was found in the three studies that
evaluated that endpoint (Kallen et al.
2000; Magnus et al 1999; Aschengrau et
al 1993).
Bove et al (2002) concluded that the
current reproductive and developmental
epidemiological database for exposure
to chlorinated byproducts in drinking
water presents moderate evidence for
associations between DBF exposure and
SGA, neural tube defects and
spontaneous abortion. The authors
acknowledged the difficulties in
assessing exposure with any precision
in the studies reviewed, but held the
opinion that misclassification of
exposure would tend to underestimate
rather than overestimate the risk.
3. Nieuwenhuijsen et al 2000
Nieuwenhuijsen et al (2000)
reviewed the toxicological and
epidemiological literature and evaluated
the potential risk of chlorination DBFs
on human reproductive health. The
authors state that "some studies have
shown associations for DBFs and other
outcomes such as spontaneous
abortions, stillbirths and birth defects,
and although the evidence for these
associations is weaker it is gaining
weight." Nieuwenhuijsen et al. also
concluded that, "although studies report
small risks that are difficult to interpret,
the large number of people exposed to
chlorinated water supplies constitutes a
public health concern."
4. Additional Epidemiology Studies
Three new reproductive and
developmental epidemiological studies
were completed that were not included
in the Reif et al. 2000, Bove et al 2002,
or Nieuwenhuijsen et al 2000 literature
reviews.
Waller et al. 2001, recalculated the
total trihalomethane exposures from
their original publication (Waller et al
1998) to evaluate two exposure
assessment methods (closest site and
utility-wide average). The new
calculations were intended to reduce
exposure misclassification by
employing weighting factors and subset
analyses. As in the 1998 publication, the
new methods found a relationship
between spontaneous abortion and THM
exposure, although the unweighted
utility-wide point estimate was lower
than reported in the original
manuscript.
Hwang et al 2002, assessed the effect
of water chlorination byproducts on
specific birth defects in Norway by
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49559
classifying exposure on the basis of
chlorination (yes/no) and amount of
natural organic matter in the water.
Statistically significant associations
with exposure were found for risks of
any birth defect, cardiac, respiratory,
and urinary tract defects. For specific
birth defects, a statistically significant
association was found for a defect of the
septum in the heart.
Windham et al., 2003, assessed the
relationship between exposure to THMs
in drinking water and characteristics of
the menstrual cycle among 403 women
who provided daily urine samples for
an average of 5.6 cycles. Women whose
tap water had TTHM levels more than
0.060 mg/1 had statistically significantly
shorter menstrual cycles than women
whose tap water had lower TTHMs. On
average, the menstrual cycles of women
with the higher levels of TTHMs were
one day shorter than cycles of women
with the lower levels (adjusted
difference: -1.1 days, 95% confidence
interval: -1.8 days to - 0.4 days). This
shortening occurred during the first half
of the cycle, before ovulation (adjusted
difference: -0.9 days; 95% confidence
interval: -1.6 days to -0.2 days). There
were no changes in bleed length or in
the regularity of the cycles. Based on
their study, Windham et al., 2003,
suggested'that THM exposure may affect
ovarian function, but since this is the
first study to examine human menstrual
cycle variation in relation to THM
exposure, more research is needed to
confirm the relationship. The public
health implication of a small reduction
in menstrual cycle length is not clear,
but if THMs are related to disturbances
in ovarian function, that might provide
insight into the observed associations
between THMs and a variety of adverse
reproductive outcomes.
EPA's epidemiology research program
continues to examine the relationship
between exposure to DBFs and adverse
developmental and reproductive effects.
The Agency is supporting several
studies using improved study designs to
provide better information for
characterizing potential risks. Details on
EPA's epidemiology research program
can be found at http://
cfint.rtpnc.epa .gov/dwportal/cfm/
dwMDBP.cfm.
B. Reproductive and Developmental
Toxicology
Several new reproductive and
developmental toxicology studies have
become available since the December
1998 Stage 1 DBPR. This discussion
presents some conclusions derived from
these studies and reports, including
hazard identification, as well as
implications for the Stage 2 DBPR.
EPA conducted a literature search of
animal toxicology studies on chronic
and subchronic DBF exposures
associated with reproductive and
developmental health effects, evaluated
the current reproductive and
developmental toxicological database
for several individual DBFs, and
assessed two independent reviews (Tyl
2000 and WHO 2000). As a result of
these analyses, EPA has concluded that
although the database is not strong
enough to quantify risk, it is sufficient
to support a hazard concern. This
hazard concern supports the need to
address potential reproductive and
developmental health effects in the
Stage 2 DBPR. The following section
describes how this conclusion was
reached.
1. EPA Analysis and Research
Since the Stage 1 DBPR, EPA has
continued to support reproductive and
developmental toxicological research on
various disinfection byproducts through
extramural and intramural research
programs. Information on EPA's
toxicology programs can be found at
http://www.epa.gov/nheerl/. These
studies, along with data on several DBFs
published after the 1998 Stage 1 DBPR,
are summarized in the updated
children's health document, "Health
Risks to Fetuses, Infants, and Children:
A Review" (USEPA 2003a).
In addition to this compilation of
data, EPA has also prepared individual
health criteria documents that provide
detailed summaries of the relevant new
information, as well as an overall
characterization of the human health
risks from exposure to certain DBFs
(USEPA 2003b-USEPA 2003h, USEPA
20031). From these new evaluations,
EPA has concluded that several new
studies on individual byproducts
contribute to the weight of evidence for
an association between DBF exposure
and adverse effects on the developing
fetus and reproduction. These effects
include fetal loss, cardiovascular effects,
and male reproductive effects and are
associated with bromodichloromethane
(BDCM), dichloroacetic acid (DCAA),
trichloroacetic acid (TCAA),
bromochloroacetic acid (BCAA), and
dibromoacetic acid (DBAA). The data
from these new studies do not change
the MCLGs that were established as a
part of the Stage 1 DBPR.
2. Tyl 2000
Tyl (2000) conducted a
comprehensive review of the
reproductive and developmental
toxicology literature on DBFs
representing over thirty-five studies.
Adverse effects reported by these
studies include developmental effects,
whole litter resorption, reduced fetal
body weights, and male reproductive
effects (e.g., inhibited spermiation,
increased abnormal sperm). Many of
these studies are categorized as high-
dose, short-term screening studies that
can be used to assess potential hazard
(Table III-l), while the long term, two-
generation reproduction studies could
be an appropriate basis for quantitative
risk assessment.
Disinfectant/DBP
Screening
Developmental 2
Two-generation 3
reproductive
Chlorine
Chlorine Dioxide
Chloramine
Chloroform
Bromoform
Bromodichloromethane ...
Dibromochloromethane ...
Monochloroacetic acid
Dichloroacetic acid
Trichloroacetic acid
Monobromoacetic acid ....
Dibromoacetic acid
Tribromoacetic acid
Bromochloroacetic acid ...
Bromodichtoroacetic acid
Dibromochtoroacetic acid
in progress
in progress
in planning stage
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Disinfectant/DBP
MX
Chlorite
Screening 1
^
^
^
j/
^
^
^
^
^
^
^
^
^
Developmental 2
^
^
^
^
^
i/
i/
Two-generation 3
reproductive
^
• denotes the availability of at least one study in the following categories.
1 Screening studies are for hazard identification. These types of studies include the following: whole embryo culture, NTP 35-day screening
studies, Chernoff-Kavlock and its modified version, and short-term male reproductive toxicity screen.
2 Developmental studies are used for dose-response determinations.
3Two-generation reproductive studies are multi-generation reproductive toxicity studies used for dose-response determinations.
Tyl concluded that, "The screening
studies, performed for a number of '
DBFs, are 'adequate' and 'sufficient'
only to detect potent reproductive/
developmental toxicants for hazard
identification." Tyl further confirms
that the database identifies certain DBFs
with potential reproductive or
developmental effects (Table III-2) and
these are discussed further in the next
section.
TABLE 11I-2.— POTENTIAL HAZARDS OF DBPs FOR REPRODUCTIVE AND DEVELOPMENTAL EFFECTS (ADAPTED FROM TYL,
2000)
Type of hazard
Disinfection byproducts
Developmental defects
Whole litter resorption
Fetotoxicity {reduced fetal body weights, increased variations)
Male reproductive effects (spermatotoxic)
TCAA, DCAA, MCAA and chlorite.
Chloroform, bromoform, BDCM, DBCM, DCAA, TCAA, DCAN, and
TCAN.
Chloroform, BDCM, DBCM, DCAA, TCAA, DCAN, TCAN, DBAN,
BCAN, MCAN.
DCAA, DBAA, BDCM.
a. Developmental defects. Tyl noted
that adverse developmental effects that
were reported from whole embryo
culture tests on the developing heart,
neural tube, eye, pharyngeal arch, and
somites tended to be associated with
haloacetic acids tested at high doses
(Hunter et al. 1996; Saillenfait et al
1995, Smith et a]. 1989). Cardiovascular
effects were also observed in vivo for
TCAA and DCAA from developmental
segment II toxicity studies at high doses
(Smith efaA 1988,1990).
b. Whole litter resorption. Whole litter
resorption, likened to miscarriage or
spontaneous abortion by Tyl 2000, was
also observed at high doses in vivo for
a range of DBPs as indicated in Table
III-2 (Murray et a]. 1979, Balster and
Borzellca, 1982, Narotsky et al. 1992;
1997 a, b; Bielmeier et al 2001; Smith
et aL 1990; Smith et al. 1988). Tyl noted
that similar effects were observed in
several epidemiology studies.
c. Fetal toxicity. Fetal toxic effects
such as reduced fetal body weights and
increased variation were observed at
high doses in vivo for a range of DBPs
(e.g., chloroform, BDCM, DBCM, DCAA,
TCAA, DCAN, TCAN, DBAN, BCAN)
(Thompson et al. 1974; Schwetz et al.
1974; Murray et aL 1979; Ruddick et al.
1983; Narotsky et al. 1992, Balster and
Borzelleca, 1982; Smith et al. 1990).
Again, Tyl noted a similarity in effects
observed in epidemiology studies.
d. Male reproductive effects. Animal
toxicology studies report increased risks
of adverse effects on the male
reproductive system from high doses of
haloacetic acids and other DBPs that
have not been studied in human
epidemiology studies. Male
reproductive effects (e.g., inhibited
spermiation, reduced epididymus,
sperm number and motility, increased
abnormal sperm, testicular damage and
inhibited in vitro fertilization) were
reported for DCAA, DBAA, TCAA and
BDCM (Toth et al. 1992, Linder et al.
1997a, b; Linder et al. 1994a, b; Cosby
and Dukelow 1992). Dr. Tyl noted that
the adverse effects observed in the male
reproductive toxicity screening studies
(Toth el al. 1992; Linder et al. 1994a, b;
19,97a, b) are confounded by a short
dosing regimen and administration of
test doses to only adult males.
From her review of the
comprehensive animal toxicology
database on reproductive and
developmental health effects from DBF
exposure, Dr. Tyl concludes that "some
DBPs have an intrinsic capacity to do
harm, specifically to the developing
conceptus and the male (and possibly
the female) reproductive system". She
concludes that "there is hazard to
development from the haloacetic acids
(TCAA, DCAA, MCAA) and acetate; to
development from chloroform,
bromoform, BDCM, DBCM, DCAA,
TCAA, DCAN, and TCAN expressed as
full litter resorption (which most likely
indicates maternal endocrine/uterine
effects); and fetotoxicity for chloroform,
BDCM, DBCM, DCAA, TCAA, DCAN,
TCAN, DBAN, BCAN, CAN,
acetaldehyde, and possibly
formaldehyde. Reproductive hazard
exists for DCAA, DBAA, and possibly ,
formaldehyde in males and for TCE and
possibly formaldehyde in females."
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3. World Health Organization Review of
the Reproductive and Developmental
Toxicology Literature (2000)
The International Programme on
Chemical Safety (IPCS) published an
evaluation of Disinfectants and DBFs in
its Environmental Health Criteria
monograph series (WHO 2000). In this
review of the toxicology data on
reproductive and developmental effects
from DBF exposure, the World Health
Organization (WHO) concludes that
although the data on these effects are
not as robust as the cancer database,
these effects are of potential health
concern. The WHO concludes that
reproductive effects in females have
been principally embryolethality and
fetal resorptions associated with the
haloacetonitriles (trichioroacetonitrile,
dichloroacetonitrile,
bromochloroacetonitrile, and
dibromoacetonitrile) and the
dihaloacetates, while DCAA and DBAA
have both been associated with adverse
effects on male reproduction.
4. New Studies
Christian et ol. (2001) conducted a
developmental toxicity study with
pregnant New Zealand White rabbits
exposed to BDCM in drinking water at
concentrations of 0,15, 150, 450, and
900 ppm in drinking water on gestation
days 6-29. The no observed adverse
effect level (NOAEL) and lowest
observed adverse effect level (LOAEL)
identified for maternal toxicity in this
study were 13.4 mg/kg-day (150 ppm)
and 35.6 mg/kg-day (450 ppm),
respectively, based on decreased body
weight gain. The developmental NOAEL
was 55.3 mg/kg-day (900 ppm) based on
absence of statistically significant, dose-
related effects at any tested
concentration. Christian et al. (2001)
also conducted a developmental study
of BDCM in a second species, Sprague-
wley rats. Rats were exposed to
3DCM in the drinking water at
concentrations of 0, 50,150, 450, and
900 ppm on gestation days 6 to 21. The
concentration-based maternal NOAEL
and LOAEL for this study were 150 ppm
and 450 ppm, respectively, based on
statistically significant, persistent
eductions in maternal body weight and
»ody weight gains. Based on the mean
consumed dosage of
iromodichloromethane, these
concentrations correspond to doses of
18.4 mg/kg-day and 45.0 mg/kg-day,
espectively. The concentration-based
developmental NOAEL and LOAEL
were 450 ppm and 900 ppm,
espectively, based on a significantly
lecreased number of ossification sites
fetus for the forelimb phalanges
(bones of the hand or the foot) and the
hindlimb metatarsals and phalanges.
These concentrations correspond to
mean consumed doses of 45.0 mg/kg-
day and 82.0 mg/kg-day, respectively.
Christian et a!. (2002b) summarized
the results of a two-generation
reproductive toxicity study on
bromodichloromethane conducted in
Sprague-Dawley rats.
Bromodichloromethane was
continuously provided to test animals in
the drinking water at concentrations of
0, 50,150, or 450 ppm. Average daily
doses estimated for the 50, 150, and 450
ppm concentrations were reportedly 4.1
to 12.6,11.6 to 40.2, and 29.5 to 109 mg/
kg-day, respectively. The parental
NOAEL and LOAEL were 50 and 150
ppm, respectively, based on statistically
significant reduced body weight and
body weight gain; Fl and F2 generation
pup body weights were reduced in the
150 and 450 ppm groups during the
lactation period after the pups began to
drink the water provided to the dams.
Body weight and body weight gain were
also reduced in the 150 and 450 ppm Fl
generation males and females. A
marginal effect on estrous cyclicity was
observed in Fl females in the 450 ppm
exposure group. Small (<6%), but
statistically significant, delays in Fl
generation sexual maturation occurred
at 150 (males) and 450 ppm (males and
females) as determined by timing of
vaginal patency or preputial separation.
The study's authors considered these
effects to be a secondary response
associated with reduced body weight,
which appears to be dehydration
brought about by taste aversion to the
compound. The results of this study
identify NOAEL and LOAEL values for
reproductive effects of 50 ppm (4.1 to
12.6 mg/kg-day) and 150 ppm (11.6 to
40.2 mg/kg-day), respectively, based on
delayed sexual maturation.
Bielmeier et al. (2001) conducted a
series of experiments to investigate the
mode of action in
bromodichloromethane-induced full
litter resorption (FLR). The study
included a strain comparison of F344
and Sprague-Dawley (SD) rats. In the
strain comparison experiment, female
SD rats (13 to 14/dose group) were
dosed with 0, 75, or 100 mg/kg-day by
aqueous gavage in 10% Emulphor® on
CD 6 to 10. F344 rats (12 to 14/dose
group) were dosed with 0 or 75 mg/kg-
day administered in the same vehicle.
The incidence of FLR in the
bromodichloromethane-treated F344
rats was 62%, while the incidence of
FLR in SD rats treated with 75 or 100
mg/kg-day of bromodichloromethane
was 0%. Both strains of rats showed
similar signs of maternal toxicity, and
the percent body weight loss after the
first day of dosing was comparable for
SD rats and the F344 rats that resorbed
their litters. The rats were allowed to
deliver and pups were examined on
postnatal days 1 and 6. Surviving litters
appeared normal and no effect on post-
natal survival, litter size, or pup weight
was observed. The series of experiments
conducted by Bieimeier et al. (2001)
identified a LOAEL of 75 mg/kg-day (the
lowest dose tested) based on FLR in
F344 rats. A NOAEL was not identified.
Mechanistic studies indicate that
BDCM-induced pregnancy loss is likely
to be luteinizing hormone (LH)-
mediated (Bielmeier et al., 2001). It is
possible that BDCM alters LH levels by
disrupting the hypothalamic-pituitary-
gonadal axis or by altering the
responsiveness of the corpora lutea to
LH. Since these possible mechanisms
are potentially relevant to pregnancy
maintenance in humans, EPA believes
the finding of BDCM-induced pregnancy
loss in F344 rats is relevant to risk
assessment, and may provide insight
into the epidemiological finding of
increased risk of spontaneous abortion
associated with consumption of BDCM
(Waller efoj. 1998, 2001).
Christian et al. (2002a) recently
completed a two-generation drinking
water study of DBA in rats. Male and
female Sprague-Dawley rats (30/sex/
exposure group) were administered
DBA in drinking water at concentrations
of 0, 50, 250, or 650 ppm continuously
from initiation of exposure of the
parental (P) generation male and female
rats through weaning of the F2 offspring.
Based on testicular histomorphology
indicative of abnormal spermatogenesis
in P and Ft males, the parental and
reproductive/developmental toxi city
LOAEL and NOAEL are 250 and 50
ppm, respectively.
Previous studies by EPA have
reported adverse effects of DBA,
administered via oral gavage, on
spermatogenesis that impacted male
fertility (Linder et al. 1994a, 1995,
1997a) at doses-comparable to those
achieved in the Christian et al. (2002a)
study. Based on these studies
collectively, it is clear that DBA is
spermatotoxic. Moreover,
Veeramachaneni et al. (2000) reported
in an abstract that sperm from male
rabbits exposed to DBA in utero from
gestation days 15 and throughout life
reduced the fertility of artificially
inseminated females as evidenced by
reduced conceptions. When published,
this study may support the evidence
that DBA is a male reproductive system
toxicant.
In addition, research on DBA by
KHnefelter et al. (2001) has
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demonstrated statistically significant
delays in both vaginal opening and
preputial separation using the body
weight on the day of acquisition
(postnatal day 45) as the co-variant. This
was not found by Christian et a] (2002a)
using the body weight at weaning as the
statistical covariant. However, the
authors analyzed the data for preputial
separation and vaginal opening with
body weight on the day of weaning as
a co-variant rather than body weight on
the day of acquisition, i.e., the day that
the prepuce separates or the day the
vagina opens. It is likely that there was
an increase in body weight from
postnatal day 21 (weaning) until
preputial separation (day 45) that was
independent of the delay in sexual
maturation.
Although the Christian et al (2002a)
study was conducted in accordance
with EPA's 1998 testing guidelines, EPA
has incorporated newer, more
sophisticated measures into recent
intramural and extramural studies that
have not yet been incorporated into the
testing guidelines. Such measures
include measuring changes in specific
proteins in the sperm membrane
proteome and fertility assessments via
in utero insemination. EPA believes that
additional research is needed, utilizing
these newer toxicologicaJ measures, to
clarify the extent to which DBA poses
human reproductive or developmental
risk. The database on male reproductive
effects from exposure to DBA is
incomplete and is not suitable for
quantitative risk assessment at this time.
It does, however, identify reproductive
effects as an area of concern.
C. Conclusions Drawn From the
Reproductive and Developmental
Health Effects Data
EPA believes that the weight of
evidence of the best available science, in
conjunction with the widespread
exposure, supports regulatory changes
that target peak DBF exposures
specifically through the Stage 2 DBPR.
Several epidemiology studies found
statistically significant associations
between exposure to chlorinated
drinking water and fetal growth,
spontaneous abortion, stillbirth, and
neural tube defects. Although
uncertainties remain and the current
database does not support a quantitative
reproductive and developmental risk
assessment for most of the DBPs, the
weight of evidence provides an
indication of a hazard concern that
warrants additional regulatory action
beyond the Stage 1 DBPR.
Biological plausibility for the effects
observed in epidemiological studies has
been demonstrated through various
toxicological studies. Tyl 2000 states
that "effects observed in animal studies
included embryonic heart and neural
tube defects from haloacetic acids in
vitro and in vivo, and full litter
resorption, reduced numbers of
implants per litter, and reduced fetal
body weight per litter were also
observed from exposure to specific
trihalomethanes. Comparable effects
were also observed in children in some
(but not all) epidemiological studies,
with exposure to trihalomethanes
(THMs) usually used as a surrogate for
specific DBP classes or individual DBPs,
as follows: increased incidences of
cardiac defects (Bove et al 1995) and of
neural tube defects in children (Bove et
al 1995; Dodds et al 1999; Klotz and
Pyrch 1998) were reported. Intrauterine
growth retardation (IUGR,
approximately equivalent to reduced
fetal body weights per litter) was
reported to be associated with
waterborne chloroform (Kramer et al.
1992; Bove et al 1995; Gallagher et al.
1998). Miscarriage or spontaneous
abortion, or stillbirth (approximately
equivalent to whole litter resorption,
reduced numbers of total and/or live
implants per litter, and increased
resorptions per litter) were observed by
Waller et al., 1998; Dodds et al., 1999;
andBoveetaA, 1995."
Similarity of effects between animals
and humans lends credence to and
strengthens the weight of evidence for
an association between adverse
reproductive and developmental health
effects and exposure to chlorinated
surface water. EPA believes that the
weight of evidence of both the
reproductive and developmental
toxicological and epidemiological
databases suggests that exposure to
DBPs may induce potential adverse
health effects on reproduction and fetal
development at some DBP exposures.
However, additional toxicological work
is necessary to identify the mode of
action for the effects observed,
D. Cancer Epidemiology
Epidemiological studies on cancer
provide valuable information that
contributes to the overall evidence on
the potential human health hazards
from exposure to chlorinated drinking
water. In the area of epidemiology, a
number of studies have been conducted
to investigate the relationship between
exposure to chlorinated surface water
and cancer. While EPA cannot conclude
there is a causal link between exposure
to chlorinated surface water and cancer,
some studies have found an association
between bladder, rectal and colon
cancer and exposure to chlorinated
surface water.
1. Population Attributable Risk Analysis
Some epidemiological studies have
linked the consumption of chlorinated
surface waters to an increased risk of
two major causes of human mortality in
the United States, colorectal and
bladder cancers (Cantor 1998). Bladder
cancer was chosen as the primary
endpoint of concern in the Stage 1
DBPR (USEPA 1998f) economic analysis
because it had the most consistent
database for a possible association to
chlorinated surface water exposure.
More studies have considered bladder
cancer than any other cancer. EPA used
the published mean risk estimates from
five studies to quantify the potential
range of risk for bladder cancer from
DBP exposure. These risks were
expressed as a range of population
attributable risks (PAR) of 2-17%
(USEPA 1998f). This means that if the
associations reported in the studies turn
out to reflect a causal link, between 2
and 17% of new bladder cancer cases
could be attributable to DBPs. This PAR
range also represents that portion of the
bladder cancer cases that would not
have occurred if the exposure to
chlorinated drinking water were absent.
A complete discussion of the Stage 1
DBPR bladder cancer PAR evaluation,
including uncertainties and
assumptions, can be found in the Stage
2 DBPR Economic Analysis (USEPA
2003S).
While EPA recognized the limitations
of the epidemiological database for
making risk estimates, the Agency
believed that it was useful for
developing an estimate of bladder
cancer risk. The PARs were derived
from measured risks (Odds Ratios and
Relative Risk) based on the number of
years exposed to chlorinated surface
water. The uncertainties associated with
these PAR estimates are largely due to
the common prevalence of both the
disease (bladder cancer) and exposure
(chlorinated drinking water). EPA
recognizes that risks from chlorinated
drinking water may be lower or higher
than those estimated from the
epidemiological literature, and that the
PAR range could include zero or be
higher than 17%.
Using the PARs of 2% and 17%, EPA
estimated that the number of possible
bladder cancer cases per year
potentially associated with exposures to
DBPs in chlorinated drinking water
could range from 1,100 to 9,300 cases.
This was based on the estimate of
54,500 new bladder cancer cases per
year nationally, as projected by the
National Cancer Institute for 1997. A
thorough discussion of cancer studies
published prior to 1998 and possible
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49563
associations with DBF exposure can be
found in the Stage 1 DBPR (USEPA
1998c).
2. New Epidemiological Cancer" Studies
New studies published since the Stage
1 DBPR continue to support an
association between bladder, colon and
rectal cancers and exposure to
chlorinated surface water (Yang et al,
1998; Koivusalo et al. 1998; King et al
2000b). Based on the weight of evidence
provided by the cancer epidemiology
database, EPA has chosen to use the
same PAR analysis to estimate the
primary benefits from bladder cancer
cases potentially avoided as a
consequence of reducing the DBP levels
from the Stage 2 DBPR (see section VII).
For the Stage 2 DBPR analysis, EPA
updated the 1997 estimate of new
bladder cancer cases per year nationally
from 54,500 to 56,500 [projected by the
American Cancer Society, 2002) and
accounted for the reductions in DBP
exposure that were projected for the
Stage 1 DBPR.
a. New bladder cancer studies.
Bladder cancer and chlorinated DBP
exposure has historically been the most
strongly supported association of all the
possible cancers, based on human
evidence. Two new studies (Yang et al.
1998 and Koivusalo et al, 1998) also
suggest an association of DBP exposure
with bladder cancer. Yang et al, 1998
found a positive association between
consumption of chlorinated drinking
water and bladder cancer. Koivusalo et
al. (1998) found evidence of increased
risk as a function of increasing DBP
exposure duration. Long exposure
durations (>45 years for Koivusalo et al.
1998) were associated with about a two-
fold increase in risk. The new bladder
cancer studies continue to support an
association and potential for a causal
relationship between exposure to
chlorination byproducts and risk for
bladder cancer.
A new publication by C.M. Villanueva
et al. (Villanueva et al. 2003) reports on
their meta-analysis of case-control and
cohort studies. This meta-analysis may
be useful for improving the estimate of
national population attributable risk
(fraction of bladder cancer cases in the
U.S. that may be attributed to
chlorinated drinking water). Compared
to EPA's current approach (i.e.,
providing a range of population
attributable risks (PAR)), use of the
meta-estimate would provide a more
stable result because:
• It provides a single (meta) estimate
of the odds ratio from which to calculate
the PAR, thereby summarizing the
results across studies, thus reducing the
influence of geographic and temporal
differences.
• It uses three additional high-quality
studies not included in the PAR range
analysis conducted by EPA (i.e., studies
by Koivusalo et al. 1998, Doyle et al.
1997, and Vena et al. 1993).
• It weights the individual studies
according to their precision, so more
precise estimates (due principally to
greater numbers of cases) carry greater
statistical weight and therefore have
greater influence on the meta-estimate.
* In addition to the primary analysis,
the authors conducted an evaluation of
the robustness of their conclusions.
They examined the sensitivity of
estimates to decisions made with
respect to exposure definitions, cut
points defining exposure groups,
inclusion/exclusion of individual
studies, and potential publication bias.
The meta-analysis provided at least
two meta-estimates that may be useful
for estimating national population
attributable risk:
• A combined odds ratio for ever-
exposure, with confidence intervals and
* A combined dose-response
regression slope coefficient, relating
increasing odds ratios to additional
years of chlorinated drinking water
consumption.
EPA conducted an estimate of the
impact of using the meta-analysis to
provide a perspective on the national
population attributable risk. This
estimate is based on the author's
correction of a minor transcription error
in their published manuscript (the
appropriate estimate for the King study
yields corrected over-all odds ratio for
ever-consumers of 1.2 with 95%
confidence interval of 1.091 to 1.320,
personal communication from M.
Kogevinas to M. Messner, 5/19/2003).
Assuming 70% of the U.S. population is
in the ever-consumed category (based
on the chlorinated surface water
exposed population), a point estimate of
the population attributable risk using
the odds ratio from the meta-analysis is
12% (95% interval 6% to 18%).
Although EPA's population attributable
risk range (2% to 17%) was not
intended to convey a quantified level of
confidence, it is not vastly different
from the meta-analysis' 95% confidence
range of 6% to 18%. EPA regards the
meta-range as additional support for
EPA's population attributable risk range.
The meta-analysis provides continued
support for an association between
exposure to chlorinated surface water
and bladder cancer.
EPA requests comment on the use of
a meta-estimated odds ratios to estimate
national population attributable risk for
the purpose of supporting the benefit
analysis for this rule, either based
specifically on the Villanueva et al.
publication or on the application of a
similar approach. EPA also solicits
comments and suggestions for use of the
combined dose-response regression
slope coefficient associated with the
increased risk of bladder cancer for each
additional year's exposure to DBFs in
drinking water for estimating the drop
in risk associated with a reduction in
DBFs as part of the benefit analysis of
this rule. EPA provides further
discussion and solicitation of comment
on how the slope factor might further be
considered in estimating the benefits of
this rule in the economic section of this
preamble.
b. New colon cancer studies.
Colorectal cancer is the third most
common type of new cancer cases and
deaths in both men and women in the
U.S. It is estimated that 148,300 new
colorectal cancer cases will be
diagnosed in 2002, with 56,600
resulting in deaths (American Cancer
Society, 2002). Human epidemiology
studies on chlorinated surface water
have reported associations with
colorectal cancer. Since the Stage 1
DBPR, two new human epidemiology
studies (Yang et al. 1998 and King et al.
2000b) have been conducted to
investigate the relationship between
colon cancer and exposure to
chlorinated surface water. Yang et al.
1998 did not identify an association
between consumption of chlorinated
drinking water and colon cancer. The
King et al. (2000b) study found evidence
of a DBP association with colon cancer
among males, but no association was
observed among females.
Similarity of effects reported in
animal toxicity and human
epidemiology studies strengthen the
weight of evidence for an association
between DBP exposure and colon
cancer. Effects observed in animal
studies which included tumors in
BDCM exposed rats and mice at several
sites (NTP 1987); colon tumors in
bromoform exposed rats (NTP 1989);
and development of aberrant crypt foci,
a preneoplastic lesion of colon cancer in
animals exposed to DBP mixtures
(DeAngelo et al. 2002), are comparable
to observations in some cancer
epidemiological studies showing an
association with colorectal cancer and
consumption of chlorinated water (King
et al. 2000b).
Even with the additional study
showing an association, the
epidemiological database on colon
cancer as a whole is not as strong as that
for bladder cancer. However, this new
study increases the weight of evidence
of an association between DBP exposure
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and colon cancer. The Stage 1 DBPR
(USEPA 1998c) includes additional
discussion of colon cancer risks
associated with DBF exposure.
c. New rectal cancer studies. The
evidence for an association between
DBFs and rectal cancer is stronger than
for colon cancer. Yang et al (1998) and
Hildesheim et al. (1998) both found
associations between chlorinated
drinking water exposure and rectal
cancer, and the associations had a
similar magnitude in both sexes.
Hildesheim et al. also found an
association in both sexes with lifetime
average THM concentration. The
consistency of the dose-response trends,
the consistency between sexes, and the
apparent control of important potential
confounders in this study all support
the observed associations.
d. Other cancers. Two new human
epidemiology studies support the
possibility of an association between
DBFs and kidney cancer. Yang et al.
(1998) found a positive association for
both males and females between
consumption of chlorinated drinking
water and kidney cancer. Koivusalo et
al. (1998) found a small, statistically
significant, exposure-related excess risk
for kidney cancer for males. The
association for females was not
significant in the Koivusalo et al, 1998
study. The current database for this
endpoint of cancer, however, is
insufficient to conclude an association.
Cantor et al. (1999) studied brain
cancer, focusing on gliomas. None of the
exposure variables were related to brain
cancer among females, but males
showed a statistically significant,
monotonically increasing risk associated
with duration of exposure to chlorinated
surface water. This study suggests a
possible association between
chlorination byproducts and gliomas;
however, the evidence from this study
is not strong enough to support a
conclusion of a causal association.
Infante-Rivard et al. (2001) conducted
a population-based case-control study in
Quebec Province, Canada, to examine
possible associations between
childhood acute lymphoblastic
leukemia and THMs. There were no
associations with leukemia for any of
the exposure indices for total THM, or
specific THMs. Therefore, the study
does not provide evidence of an
association between any of the exposure
variables and childhood leukemia.
3. Review of the Cancer Epidemiology
Literature (WHO 2000)
The International Programme on
Chemical Safety (IPCS) report on
disinfectants and disinfection
byproducts (WHO 2000) concludes that
results of analytical epidemiological
cancer studies are insufficient to
support a causal relationship for
bladder, colon, rectal, or any other
cancer and chlorinated drinking water
or THMs. The report notes that there is
better evidence for an association
between exposure to chlorinated surface
water and bladder cancer than for other
types of cancer. The WHO also
concludes that based on the large
number of people exposed to
chlorinated drinking water, there is a
need to address this potential health
concern.
E. Cancer and Other Toxicology
Few new cancer toxicology studies
have been completed since the Stage 1
DBPR was finalized in December 1998.
The information provided in the
following sections adds to the
toxicology database and provides
additional support for the Stage 2 DBPR
to control DBF peaks (e.g. high TTHM
and HAAS levels) throughout
distribution systems, but does not
change the quantitative assessment of
the MCLGs.
1. EPA Criteria Documents
To date, EPA has established lifetime
cancer risk levels for four DBFs
(bromoform, bromodichloromethane,
bromate, and dichloroacetic acid)
classified as "probable" carcinogens, as
promulgated in the Stage 1 DBPR and
reported in the Integrated Risk
Information System (IRIS). Although
researchers have continued to assess the
cancer risks of DBFs, there has been
little change in the overall DBF
carcinogenicity database since the Stage
1 DBPR.
The most significant new publication
since the Stage 1 DBPR was a study of
DCAA tumorigenicity in mice by
DeAngelo et al. (1999). The Agency has
used the data from this study to revise
the slope factor for DCAA and a
drinking water 10~6 lifetime cancer risk
concentration. The slope factor is a
measure of the potency of a carcinogen
while the 10~f) lifetime cancer risk
concentration provides an estimate of
the concentration of a contaminant in
drinking water that is associated with an
estimated excess lifetime cancer risk of
one in a million (Table III-3).
Another significant advancement
beyond the Stage 1 DBPR was the
evaluation of the chloroform
tumorigenicity data on the basis of its
nonlinear mode of action following the
draft 1999 proposed Guidelines for
Carcinogen Risk Assessment (USEPA
I999a). The new chloroform assessment
became available on IRIS (2001) in
October, 2001 (see section V for a more
detailed discussion).
The Criteria Documents for
bromoform, bromodichloromethane,
dibromochloromethane, and
dichloroacetic acid that support the
Stage 2 proposal include cancer slope
factors and 10~6 lifetime cancer risk
concentrations that have been modified
from their Stage 1 values in order to
reflect the methodology proposed in the
1996/1999 draft cancer guidelines
(USEPA 1999a) (Table III-3). These
include the values based on the
Maximum Likelihood Estimate of the
dose producing effects in 10 percent of
the animals (EDui) and from the lower
95 percent confidence bound on that
value (LEDio). Except for
dibromochloromethane, which is
classified as a possible human
carcinogen, the DBFs in Table III-3 (and
bromate as noted previously) are
classified as probable human
carcinogens.
TABLE III—3.—QUANTIFICATION OF CANCER RISK
Disinfection byproduct
Risk factors from LEDio
Slope factor
(mg/kg/day)-1
0.034
0.0045
0.04
0.048
10~6Risk
concentration
(mg/L)
0.001
0.008
0.0009
0.0007
Risk factors from ED10
Slope factor
(mg/kg/day) - '
0.022
0.0034
0.017
0.014
10-" Risk
concentration
(mg/L)
0.002
0.01
0.002
0.003
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49565
EPA believes that it is important to
pursue additional research on cancer
from DBFs. EPA has several ongoing
studies in addition to a collaboration
with the National Toxicology Program
of the National Institute of
Environmental Health Sciences. More
information on EPA's toxicology
research program can be found at http:/
/www. epa.gov/nheerl.
2. Other Byproducts with Carcinogenic
Potential
a. 3-chloro-4-(dich]oromethyl}-5-
hydroxy-2(5H)-furanone) (MX)—
multisite cancer. MX is a byproduct of
chlorination that is typically found at
very low concentrations {approximately
<0.000067 mg/L) in drinking water. The
information available on MX was
recently compiled in the Quantitative
Cancer Assessment for MX and
chlorohydroxyfuranones (USEPA
2000i). Overall, the weight of evidence
indicates that MX is a direct-acting
^enotoxicant in mammals, with the
ability to induce tumors in multiple
sites. The primary sites for tumor
formation are the thyroid and liver.
b. N-nitrosodimethylamine (NDMA)—
multisite cancer. Health effects data
indicate that NDMA is a probable
luman carcinogen, as described on IRIS
^1991). Risk assessments have estimated
that the 10~6 lifetime cancer risk level
is 0.000007 mg/L based on induction of
:umors at multiple sites. Recent studies
siave produced new information on the
occurrence and mechanism of formation
of NDMA but there is not enough
information at this time to draw
conclusions. More research is underway
to determine the mechanism by which
sJDMA is formed in drinking water, and
the extent of its occurrence in
chloraminated systems.
3. Other Toxicological Effects
The Agency has modified the
reference dose (RfD) values for 2 of the
chlorinated acetic acids since the Stage
1 DBPR. Under the .Stage 1 DBPR there
was no established RfD for
monochloroacetic acid (MCAA). Data
rom a drinking water exposure study of
MCAA in rats by DeAngelo et al (1997)
were used to establish an RfD of 0.004
mg/kg/day based on observed increases
n spleen weight. Data from DeAngelo
1997) were also used to calculate a new
tfD of 0.03 mg/kg/day for
richloroacetic acid (TCAA) based on
observed effects on body weight and
iver effects. Detailed discussions of the
new reference doses are located in
section V of this preamble.
4. WHO Review of the Cancer
Toxicology Literature (2000)
The IPCS report on Disinfectants and
Disinfection Byproducts (WHO 2000)
emphasizes that the bulk of the
toxicology data focuses primarily on
carcinogenesis. The Task Group found
BDCM to be of particular interest
because it produces tumors in both rats
and mice at several sites. Although the
HAAs appear to be without significant
genotoxic activity, the brominated
HAAs appear to induce oxidative
damage to DNA, leading to tumor
formation.
F. Conclusions Drawn From the Cancer
Epidemiology and Toxicology
EPA believes that the cancer
epidemiology and toxicology databases
provide important information that
contributes to the weight of evidence
evaluation of the potential health risks
from exposure to chlorinated drinking
water. At this time the cancer
epidemiology studies are insufficient to
establish a causal relationship between
exposure to chlorinated drinking water
and cancer, but EPA does believe there
is a potential association. The current
database is sufficient for quantitative
analysis on the endpoint of bladder
cancer, as presented previously in the
PAR analysis.
The association between DBP
exposure and colon cancer remains
more tenuous than the link to bladder
cancer, although similarity of effects
reported in animal toxicity and human
epidemiology studies strengthens the
weight of evidence for an association
between DBP exposure and colon
cancer. Studies finding potential
relationships between exposure to
chlorinated drinking water and rectal,
kidney, and brain cancer also add to the
weight of evidence for a public health
concern. EPA believes that the overall
cancer epidemiology and toxicology
data support the decision to pursue
additional DBP control measures as
reflected in the Stage 2 DBPR.
G. Request for Comment
EPA requests comment on the
conclusions drawn from the new health
information summarized in this section.
EPA requests comment on the weight of
evidence evaluation of the potential
reproductive and developmental
hazards from DBFs and its potential
implications for the regulatory
provisions for the final Stage 2 DBPR.
EPA solicits any additional data on the
reproductive or developmental effects
from DBFs that need to be considered
for the final Stage 2 DBPR.
EPA requests comment on EPA's
conclusions regarding cancer
epidemiology and toxicology, and the
new studies discussed in today's
proposal. EPA solicits any additional
cancer epidemiology and toxicology
data that need to be considered for the
final Stage 2 DBPR.
EPA also solicits any health
information available to further assess
risk to sensitive subpopulations,
especially children and the elderly.
IV. DBP Occurrence Within
Distribution Systems
New information on the occurrence of
DBFs in distribution systems raises
issues about the protection provided by
the Stage 1 DBPR. This section presents
the new information used to identify
key issues and to support the
development of the Stage 2 DBPR. For
a more detailed discussion see the Stage
2 Occurrence Assessment for
Disinfectants and Disinfection
Byproducts (USEPA 2003o).
Under the Stage 1 DBPR, compliance
with the DBP MCLs is determined by
averaging, annually and system-wide,
all DBP measurements. The following
discussion shows that compliance based
on system averages of DBP
concentrations allows a significant
number of sampling locations within
distribution systems to have DBP levels
above the MCLs. These peak DBP
occurrences are masked by averaging
with lower distribution system
occurrence levels. The populations
served by portions of the distribution
system with higher DBP concentrations
are not receiving the same level of
health protection.
The new information also shows that
the highest DBP levels often do not
occur at distribution system sites
identified as representing maximum
residence time. The information further
shows that the highest TTHM and
HAAS levels often do not occur at the
same site within the distribution
system. These two findings suggest that
it is appropriate to reevaluate the Stage
1 DBPR compliance monitoring sites in
order to target those sites with high DBP
levels. EPA believes that distribution
system compliance monitoring sites
need to be reevaluated to ensure
identification of sites that reflect both
high TTHM and HAAS occurrence.
A. Data Sources
1. Information Collection Rule Data
The Information Collection Rule
(USEPA 1996a) established monitoring
and data reporting requirements for
large public water systems. Under the
Information Collection Rule, systems
serving at least 100,000 people were
required to conduct DBP and DBP-
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related monitoring. The 18 months of
required monitoring, which began in
July 1997 and ended in December 1998.
applied to 296 public water systems
(500 treatment plants).
The Information Collection Rule data
show the national occurrence of: (1)
Influent water quality parameters; (2)
primary and secondary disinfectant Use
by the large plants; (3) occurrence of
DBFs and DBF precursors in treatment
plants, finished waters, and
distributions systems; (4) microbial
occurrence (in subpart H systems only);
and (5) treatment plant monthly
operation, and initial as well as final
treatment plant design. The data were
gathered after the Stage 1 DBPR was
finalized (USEPA 1998c) but well before
systems were required to meet Stage 1
DBPR requirements.
The Information Collection Rule
required a significant investment for the
water treatment industry, as well as for
the EPA to analyze the data. Overall, the
occurrence and treatment data collected
under the Information Collection Rule,
excluding microbial data, was estimated
to cost systems $54 million (USEPA
1996a). In addition, systems using
source waters with high DBF precursor
levels were required to conduct bench
and pilot studies to evaluate the
effectiveness of granular activated
carbon (GAG) and membrane technology
to control for DBFs. The estimated cost
for these studies totaled approximately
$57 million (USEPA 1996a).
In addition to the analysis of DBFs in
distribution systems, EPA used
occurrence data from the Information
Collection Rule to confirm selection of
TTHM and HAA5 as appropriate
contaminants for monitoring DBPs. EPA
also used occurrence data from the
Information Collection Rule to confirm
differences in monitoring requirements
for systems using surface water versus
those using ground water, as stipulated
under the Stage 1 DBR. Analysis of the
Information Collection Rule data
indicates that TTHM and HAAS
comprise on average, across all systems,
about 50% of the total mixture of
chlorinated DBPs and that TTHM and
HAA5 concentrations are much lower
and less variable in ground water
systems than in surface water systems.
These results support the basis for
continuing the use of TTHM and HAA5
as indicators for controlling chlorinated
DBPs. The data also reconfirmed that
ground water systems require jess
monitoring than surface water systems
based on lower and less variable DBF
occurrence. For detailed analysis, see
Stage 2 Occurrence Assessment for
Disinfectants and Disinfection
Byproducts (USEPA 2003o).
2. Other Data Sources Used To Support
the Proposal
Table IV-1 summarizes the data
sources other than the Information
Collection Rule used to support the
Stage 2 DBPR. The data from the
Information Collection Rule is from
large systems. To validate the
conclusions drawn from analysis of the
Information Collection Rule for small
and medium systems, EPA compared
these other data sources with the
Information Collection Rule data. EPA
found that there are significant
similarities between large systems and
medium and small systems with regard
to source water quality (affecting DBF
formation) and use of treatment
technologies. Because of these
similarities, EPA expects that small and
medium systems would find DBF
distribution system levels similar to
those found in large systems following
compliance with the Stage 1 DBPR
requirements. For detailed discussion of
this analysis, see Stage 2 Occurrence
Assessment for Disinfectants and
Disinfection Byproducts (USEPA 2003o)
and Economic Analysis for the Stage 2
Disinfection Byproducts Rule (USEPA
2003i).
TABLE IV-1 .—SUMMARY OF NON-INFORMATION COLLECTION RULE OCCURRENCE SURVEY DATA
Data source
Data collected
Geographic representation
Number of plants
(By population served)
Information Collection Rule
Supplemental Survey.
WaterStats
National Rural Water Asso-
ciation Survey (NRWAS).
State Data-Surface Water ..
State Data-Ground Water ..
Ground Water Supply Sur-
vey.
Raw source water-(Large Systems) TOC
Raw source water-(Small & Medium Survey Systems)
TOC, UV 254, bromide, turbidity, pH, & tempera-
ture.
Population served and flows
Raw source water—Water
Quality Parameters (WQPs),
Source water type.
Finished water-WQPs, TTHM, HAAs
Treatment-unit processes, disinfectant used.
Population served and flows
Raw source water-temperatures, turbidity, pH, and
source water type, bromide, TOC, UV 254, alka-
linity, calcium, and total hardness.
Finished water-residence time estimate, total and indi-
vidual THMs, individual HAAs and HAAS, HAA6,
HAA9.TOC, UV 254, Bromide, Temperature, pH,
free and total chlorine residual levels.
Treatment-unit processes, disinfectant used.
Distribution system TTHM occurrence data.
Distribution system TTHM occurrence data.
TOC and TTHM (one sample for each parameter at
the entry point to distribution system.)
Random national distribu-
tion by SW source type1.
Random national distribu-
tion.
Random national distribu-
tion.
47 serving 100,000 or
more.
40 serving 10,000-99,999.
40 serving fewer than
10,000.
219 serving 100,000 or
more.
623 serving 10,000-99,999.
30 serving fewer than
10,000.
117 serving fewer than
10,000.
AK, CA, IL, MN, MS, NC,
TX, WA2.
AK, CA, FL, IL, NC, TX,
WA2.
Random national distribu-
tion.
562 serving fewer than
10,000.
2336 serving fewer than
10,000.
979 total.
1 Source type designations include flowing stream and lake/reservoir (Except for 7 large plants pre-selected).
2 Over 50 percent of each State's systems are represented. EPA believes that the data reasonably represent a fufl range of source water qual-
ity in small systems at the national level.
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B. DBFs in Distribution Systems
EPA wanted to understand DBP
occurrence in distribution systems
likely to exist after implementation of
the Stage 1 DBPR. Such an
understanding would enable EPA to
recognize options on how to improve
protection under the Stage 2 DBPR. The
analysis of occurrence data to support
the Stage 2 DBPR is complicated
because available national occurrence
data do not reflect the changes in
occurrence resulting from the
implementation of the Stage 1 DBPR.
Many utilities have only recently
changed their treatment to comply with
the Stage 1 DBPR (subpart H systems
serving 10,000 people or more were
required to comply beginning January
2002) or are about to make changes in
treatment to comply with this rule
(subpart H systems serving fewer than
10,000 people and ground water
systems are required to comply
beginning January 2004).
To address the above issue, EPA
evaluated Stage 1 DBPR implications by
using Information Collection Rule data
from plants that would not exceed the
Stage 1 DBPR TTHM and HAA5 MCLs
as an annual average. The TTHM and
HAAS data consist of quarterly
measurements in four locations in
distribution systems associated with
each Information Collection Rule
treatment plant. Two samples were
collected at sites representing average
residence time (AVGl and AVG2), one
sample at a site intended to represent
the maximum residence time (MAX),
and one sample was reported as a
distribution system equivalent (DSE).
The DSE sample was generally
representative of average residence
times. EPA believes that the monitoring
locations of the Information Collection
Rule, while not necessarily being the
same as the Stage 1 DBPR compliance
monitoring sites, provide a close
approximation of monitoring under the
Stage 1 DBPR. EPA recognizes, however,
that data for plants that are in
compliance with Stage 1 MCLs even
without installing additional treatment
(perhaps because of low source water
TOG) are not necessarily reflective of
plants that make treatment changes to
comply with the Stage 1 DBPR.
1. DBPs Above the MCL Occur at Some
Locations in a Substantial Number of
Plants
Figure IV-1 compares the TTHM
running annual average (RAA) levels
with the single highest TTHM
concentration in the distribution
system. Twenty one percent (60 of 290)
of the Information Collection Rule
plants had single TTHM concentrations
higher than the 0.080 mg/L MGL. Figure
IV-2 makes the same comparison for
HAA5. Fourteen percent (40 of 290) of
the plants meeting the Stage 1 DBPR
MCL had single HAAS concentrations
higher than the 0.060 mg/L MCL. In
systems with a low RAA for TTHM and
HAAS, the highest single TTHM and
HAAS values are generally not much
higher than the respective Stage 1 DBPR
MCLs. However, as the RAAs increase,
there is a greater likelihood of having
peak levels above the MCLs. As the
RAAs approach the Stage 1 DBPR MCLs,
some of the distribution system single
highest concentrations approach levels
that are double the Stage 1 DBPR MCLs.
BILLING CODE 6560-50-P
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49569
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
2. Specific Locations in Distribution
Systems Are Not Protected to MCL
Levels
Data from the Information Collection
Rule show that the RAA compliance
calculation may allow specific locations
in a distribution system to regularly
receive water with DBP levels that
exceed the MCL. Figure IV-3 shows that
five percent of plants (15 out of 290) had
one or more locations that, on average,
exceeded 0.080 mg/L as a TTHM LRAA
for that same year. One of the 15 plants
that exceeded a TTHM LRAA of 0.080
mg/L did so at two locations. Of the 15
plants, the highest LRAA was between
0.080 and 0.090 mg/L at 10 plants, and
between 0.090 and 0.100 mg/L at 5
plants. Customers served at these
locations regularly received water with
TTHM concentrations somewhat higher
than the MCL.
Figure IV-4 shows similar results
based on Information Collection Rule
HAAS data. Three percent of plants
(eight of 290) exceeded 0.060 mg/L as an
LRAA, and three of these eight plants
did so at two or three locations. Of the
8 plants, the highest LRAA was between
0.060 and 0.070 mg/L at 5 plants, and
between 0.070 and 0.075 mg/L at 3
plants. Among the 290 plants in the
Information Collection Rule database
meeting the Stage 1 MCLs, 19 plants
have a maximum TTHM LRAA of 0.080
mg/1 or greater or a maximum HAAS
LRAA of 0.060 mg/1 or greater (four
plants exceeded both MCLs), though in
no case did DBP levels at a given
location consistently exceed the MCL by
more than 20%.
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49571
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49573
3. Stage 1 DBPR Maximum Residence
Time Location May Not Reflect the
Highest DBF Occurrence Levels
The 1979 TTHM rule and Stage 1
DBPR monitoring locations must
include a site reflection maximum
residence time in the distribution
system with the intent of capturing the
lighest DBF levels in the distribution
system. The Information Collection rule
referred to this specific location as
MAX. The Information Collection rule
data indicate two important results: (1)
that monitoring locations identified as
he maximum residence time locations
often did not represent those locations
with the highest DBF levels and (2) the
highest TTHM and HAA5 level often
occurred at different points in the
distribution system.
Figure IV-5 illustrates that the highest
TTHM and HAAS LRAAs could be at
any of the four Information Collection
Rule sample locations in the
distribution system or, in some cases, at
the finished water location. Fifty
percent of the plants evaluated have the
highest TTHM LRAA concentration
occurring at a site other than the
maximum residence time monitoring
site, over 60% of plants evaluated had
the highest HAAS LRAA at a location
other than the maximum residence time
monitoring site.
Figure IV-6, based on data from the
National Rural Water Survey (NRWS),
indicates that systems serving fewer
than 10,000 people also frequently have
their highest TTHM and HAAS levels at
locations other than those intended to
represent maximum residence time. The
occurrence patterns indicated in Figures
IV-5 and IV-6 may be due to several
factors, such as HHA5 degrading over
time in the distribution system,
maximum residence time monitoring
sites not actually representing the
maximum residence time, or that using
a simple estimation of maximum
residence time cannot characterize a
complex distribution system.
Figure IV-5. Frequency at Which Highest TTHM or HAAS Locational Annual Average
Concentrations Occurred at Each Information Collection Rule Sampling Location for
plants meeting Stage 1 MCLs1
60%
0
FIN
DSE
AVG1
AVG2
MAX
ICR Sampling Locations
1 Includes only the Information Collection Rule plants with at least 3 quarters of data and with each quarter having at
least 3 sampling locations for both TTHM and HAA5 during the last 4 quarters of the Information Collection Rule
sampling period.
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Figure IV-6 Frequency at Which Highest TTHM or HAAS Locational Annual Average
Concentrations Occurred at Each Monitoring Location in NRWA Survey
80% -
Note:
Finished Water Point
Average Residence
Time
Maximum Residence
Time
Sampling Locations
LRAA calculation is based on the results from two sampling events at each of sampling locations in the
NRWA survey (winter and summer months). Only plants having monitoring results for both winter and
summer months are included in the data set
EPA also analyzed whether the
highest LRAA for TTHM and HAA5
occurred at the same location. If TTHM
and HAAS occur at the same location
rather than different locations, fewer
monitoring sites would be needed to
represent TTHM and HAA5 occurrence.
However, this is not the case. The
Information Collection Rule and NRWA
data sets, respectively, indicate that
49% and 44% of plants experienced
their highest LRAA TTHM and HAA5
concentrations at different locations in
the distribution system.
For plants that did have their highest
LRAA TTHM and HAAS concentrations
at the same location, it was not
necessarily the maximum residence
time monitoring location. Figure IV-7
illustrates that for the Information
Collection Rule plants with the highest
TTHM and HAA5 levels occurring at the
same location, the highest TTHM and
HAA5 LRAA simultaneously occurred
at the maximum residence time
monitoring location in 50% of the cases.
Figure IV-8 illustrates that for the
NRWA plants with the highest TTHM
and HAAS levels occurring at the same
location, the highest TTHM and HAA5
LRAA simultaneously occurred at the
maximum residence time [MAX)
monitoring location in 64% of the cases.
C. Request for Comment
EPA requests comment on the
analysis presented in this section. Is
EPA's approach for representing post
Stage 1 DBPR occurrence appropriate?
What other approaches might be used?
Are the conclusions that EPA derives
from the analysis appropriate?
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49575
Figure IV-7. Frequency at Which Highest TTHM/HAA5 LRAAs Occurred at Same
Sampling Location (Based on the Information Collection Rule data) for plants meeting
Stage 1 MCLs.J
N=290
Maximum occurred
at different
locations for 48.6%
of plants
Maximum occurred
at same location
51.4% of plants
Highest LRAA
TTHM/HAA5
N=149
8.7% @ FINISH
8.7% @ DSE
15.4% @ AVG2
16.8%@ AVG1
50.3% @ MAX
Among Plants with Highest
LRAA TTH M/HAA5 at Same
Location
'Includes only the Information Collection Rule plants with at least 3 quarters of data and with each quarter having at
least 3 sampling locations for both TTHM and HAAS during the last 4 quarters of the Information Collection Rule
sampling period.
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Figure IV-8. Frequency at Which Highest TTHM/HAA5 LRAAs Occurred at Same
Sampling Location (Based on the data from NRWA Survey)
N=96
N=42
Maximum occurred
at different locations
for 56.3% of plants
Maximum occurred
at same locations for
43.8% of plants
64.3% @ MAX
30.9%@AVG
4.8% @ FINISH
Highest LRAA Among Plant with Highest
TTHM/HAA5 LRAA TTHM/HAA5 at Same
Location
Note: LRAA calculation is based on the results from two sampling events at each of sampling locations in the
NRWA survey (winter and summer months). Only plants having monitoring results for both winter and
summer months are included in the data set.
V. Discussion of Proposed Stage 2 DBPR
Requirements
A. MCLGfor Chloroform
\. What Is EPA Proposing Today?
EPA is proposing an MCLG for
chloroform of 0.07 mg/L based on a
cancer reference dose (RfD), an
assumption that a person drinks 2 liters
of water per day (the 90th percentile of
intake rate for the U.S. population), and
a relative source contribution (RSC) of
20 percent. The MCLG is proposed at a
level at which no adverse effects on the
health of persons is anticipated with an
adequate margin of safety. This
conclusion is based on toxicological
evidence that the carcinogenic effects of
chloroform are an ultimate consequence
of sustained tissue toxicity. The MCLG
is set at a daily dose for a lifetime at
which no adverse effects will occur
because the sustained tissue toxicity,
which is a key event in the cancer mode
of action of chloroform, will not occur
(USEPA 2001b).
EPA believes that the RfD used for
chloroform is protective of sensitive
groups, including children. This RfD
was developed by the EPA current
method for developing RfDs based on
animal data. The method is designed to
be protective by taking human
variability into account and assuming
that the average human will be as
sensitive as the most responsive animal
species. EPA's understanding of the
mode of action for chloroform does not
indicate a uniquely sensitive subgroup
or an increased sensitivity in children.
2, How Was This Proposal Developed?
a. Background. EPA proposed a zero
MCLG for chloroform in the 1994 Stage
1 DBPR proposal (USEPA 1994b).
Following the proposal, numerous
toxicological studies on chloroform
were published and were discussed in
two Notices of Data Availability
(NODAs) (USEPA 1997a; USEPA
1998e). The 1998 NODA presented
substantial scientific data related to the
mode of action as part of the chloroform
risk assessment and requested comment
on a chloroform MCLG of 0.3 mg/L that
reflected a nonlinear mode of action.
After considering comments on the
NODAs, EPA determined that further
deliberations with the Science Advisory
Board (SAB) and stakeholders were
needed before changing the MCLG for
chloroform. Thus, EPA promulgated a
chloroform MCLG of zero in the final
Stage 1 DBPR (USEPA 1998c) and
committed to conducting additional
deliberations with the SAB and
factoring the SAB's review into the
Agency's Stage 2 DBPR rulemaking
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49577
irocess. The Agency consulted with the
IAB in October 1999 (USEPA 2000f).
The Stage 1 DBPR MCLG of zero for
;hloroform was challenged, and the U.S.
>ourt of Appeals for the District of
Columbia Circuit issued an order
•acating the zero MCLG (Chlorine
Chemistry Council and Chemical
Manufacturers Association v. EPA, 206
.3d 1286 (D.C. Circuit 2000)). EPA
:ommitted to the Court to propose a
ion-zero MCLG for chloroform in the
ipcoming proposed Stage 2
)isinfectants and Disinfection
Jyproducts Rule. EPA removed the
.4CLG for chloroform from its Stage 1
)BP NPDWR (USEPA 2000e). No other
>rovision of the Stage 1 DBPR was
iffected.
b. Basis of the new chloroform MCLG.
iased on an analysis of all the available
cientific data on chloroform discussed
n more detail below, EPA believes that
:hloroform dose-response is nonlinear
ind that chloroform is likely to be
:arcinogenic only under high exposure
:onditions. EPA's assessment of the
;ancer risk associated with chloroform
exposure (USEPA 2001b) uses the
mnciples of the 1999 EPA Proposed
Guidelines for Carcinogen Risk
Assessment (USEPA 1999a). .
The Proposed Guidelines for
Carcinogen Risk Assessment, as
eviewed by the public and the EPA
?AB, reflect new science and are
:onsistent with, and an extension of, the
ixisting 1986 Guidelines for Carcinogen
iisk Assessment (USEPA 1986). The
[986 guidelines provide for departures
rom default assumptions such as low
lose linear extrapolation. For example,
he 1986 EPA guidelines reflect the
losition of the Office of Science and
fechnology Policy (OSTP) that (OSTP
1985; Principle 26) "[N]o single
nathematical procedure is recognized
is the most appropriate for low-dose
txtrapolation in carcinogenesis. When
elevant biological evidence on
nechanisms of action exists (e.g,
iharmacokinetics, target organ dose),
he models or procedure employed
ihould be consistent with the
evidence." The 1985 guidelines go on to
itate "The Agency will review each
issessment as to the evidence on
:arcinogenesis mechanisms and other
riological or statistical evidence that
ndicates the suitability of a particular
)xtrapolation model."
i. Mode of action. EPA has fully
ivaluated the science on chloroform and
;oncludes that chloroform is likely to be
:arcinogenic to humans under high
exposure conditions that lead to
cytotoxicity and regenerative
lyperplasia in susceptible tissue;
;hloroform is not likely to be
carcinogenic to humans at a dose level
that does not cause cytotoxicity and cell
regeneration (USEPA 1998e, USEPA
1998b, USEPA 2001b).
Chloroform's carcinogenic potential is
indicated by animal tumor evidence
(liver tumors in mice and renal tumors
in both mice and rats) from inhalation
and oral exposure. Data on metabolism,
toxicity, mutagenicity and cellular
proliferation contribute to an
understanding of the mode of
carcinogenic action. For chloroform,
sustained or repeated cytotoxicity with
secondary regenerative hyperplasia
precedes, and is a key event for, hepatic
and renal neoplasia.
EPA believes that a DNA reactive
mutagenic mode of action is not likely
to be the predominant influence of
chloroform on the carcinogenic process.
EPA has concluded that the
predominant mode of action involves
cytotoxicity produced by the oxidative
generation of highly reactive
metabolites, followed by regenerative
cell proliferation (USEPA 2001b). EPA
further believes that the chloroform
dose-response is nonlinear. The SAB
final report states "(t)he Subcommittee
agrees with EPA that sustained or
repeated cytotoxicity with secondary
regenerative hyperplasia in the liver
and/or kidney of rats and mice
precedes, and is probably a causal factor
for, hepatic and renal neoplasia"
(USEPA 2000f).
ii. Metabolism. The cytochrome P450
isoenzyme GYP 2E1 is the primary
enzyme catalyzing chloroform
metabolism at low concentrations.
Chloroform's carcinogenic effects
involve oxidative generation of reactive
and toxic metabolites (phosgene and
hydrochloric acid [HCl]) and thus are
related to its noncancer toxicities (e.g.,
liver or kidney toxicities). The
electrophilic metabolite phosgene could
react with macromolecules such as
phosphotidyl inositols or tyrosine
kinases which in turn could potentially
lead to interference with signal
transduction pathways (i.e., chemical
messages controlling cell division), thus
leading to carcinogenesis. Likewise, it is
also plausible that phosgene reacts with
cellular phospholipids, peptides and
proteins resulting in generalized tissue
injury. Glutathione, free cysteine,
histidine, methionine and tyrosine are
all potential reactants for electrophilic
agents.
At high concentrations, chloroform
may undergo reductive metabolism
which forms reactive dichloromethyl
free radicals. These free radicals can
contribute to lipid peroxidation and
cause cytotoxicity.
c. How the MCLG is derived. EPA
continues to recognize the strength of
the science in support of a nonlinear
approach for estimating the
carcinogenicity of chloroform. This
science was affirmed by the Chloroform
Risk Assessment Review Subcommittee
of the EPA SAB Executive Committee
which met on October 27-28,1999
(USEPA 2000f). The SAB Subcommittee
agreed that the nonlinear approach is
most appropriate for the risk assessment
of chloroform.
Nonzero MCLGs are scientifically and
statutorily supported. The statute
requires that the MCLG be set where no
known or anticipated adverse effects
occur, allowing for an adequate margin
of safety (56 FR 3533; USEPA 1991b).
Historically, EPA established MCLGs of
zero for known or probable human
carcinogens based on the principle that
any exposure to carcinogens might
represent some finite level of risk. If
there is substantial scientific evidence,
however, that indicates there is a "safe
threshold", then a nonzero MCLG can
be established with an adequate margin
of safety (56 FR 3533; USEPA 1991a)).
EPA would ideally like to use the
delivered dose (i.e., the amount of key
chloroform metabolites that actually
reach the liver and cause cell toxicity)
for calculating an RfD to support the
MCLG. However, the required
toxicokinetic data are not currently
available. Thus, the RfD is calculated
using the applied dose (i.e., the amount
of chloroform ingested). The RfD is
based on both the benchmark dose and
the traditional no observed adverse
effect level/lowest observed adverse
effect level (NOAEL/LOAEL)
approaches for hepatotoxicity in the
most sensitive species, the dog. The
MCLG is based on the RfD and
calculated as follows:
RfD x body weight x RSC
daily water consumption
i. Reference dose. The RfD for
chloroform was estimated based on
noncancer effects using both the
benchmark dose and the traditional
NOAEL/LOAEL approaches. For
benchmark analysis, five relevant data
sets including target organ toxicity,
labeling index, histopathology in
rodents, and liver toxicity in dogs
(Heywood 1979) were evaluated. The
effects seen in dogs are considered to be
early signs of liver toxicity, preceding
cytotoxicity, cytolethality and
regenerative hyperplasia. Thus, the
Heywood (1979) study, provides the
most sensitive end point in the most
sensitive species and is the most
appropriate basis for the RfD.
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The 95% confidence lower bound on
the dose associated with a 10% extra
risk (LED10) is based on tho prevalence
of animals demonstrating liver toxicity.
After an exposure adjustment to the
LED10 (1.2 mg/kg/day), an RfD of 0.01
mg/kg/day was calculated using an
overall uncertainty factor of 100 (10 for
interspecies extrapolation and 10 for
protection of sensitive individuals)
(USEPA 2001b).
Coincidentally, the benchmark dose
and the traditional NOAEL/LOAEL
approaches yield the same RfD number
(USEPA 2001bJ. The NOAEL/LOAEL
approach is also based on the Heywood
study (1979) which had a LOAEL of 15
mg/kg/day for evidence of liver toxicity.
After an exposure adjustment to the
LOAEL (yielding 12.9 mg/kg/day), an
RfD of 0.01 mg/kg/day was calculated
using an overall uncertainty factor of
1000 (10 for interspecies extrapolation,
10 for protection of sensitive
individuals, and 10 for using a LOAEL
instead of a NOAEL) (USEPA 2001bj.
ii. Relative source contribution.
Another factor in determining the
MCLG is the relative source
contribution (RSC). The RSC is used
when the MCLG is set at a level above
zero. Its purpose is to ensure that the
contribution to exposure from drinking
tap water does not cause the lifetime
daily exposure of persons to a
contaminant to exceed RfD. The RSC is
thus a factor used to make sure that the
MCLG is protective even if persons are
exposed to the contaminant by other
routes (inhalation, dermal absorption] or
other sources (e.g., food). If sufficient
quantitative data are not available on
exposure by other routes and sources,
EPA has historically assumed that the
RSC from drinking water is 20 percent
of the total exposure, a value considered
protective. If data indicate that
contributions from other routes and
sources are not significant, EPA has
historically assumed a less conservative
RSC of 80 percent (54 FR 22,062, 22,069
(May 22,1989)(USEPA 1989a), 56 FR at
3535 (Jan 30, 1990)(USEPA 1991a), 59
FR 38,668, 38,678 (July 29,
1994)(USEPA1994b)).
Today, EPA is proposing an
assumption of a 20 percent RSC. This is
in consideration of data which indicate
that exposure to chloroform by other
routes and sources of exposure may
potentially contribute a substantial
percentage of the overall exposure to
chloroform.
In the 1998 Stage 1 DBPR NODA, EPA
considered an MCLG of 0.3 mg/L that
was calculated using an RSC of 80
percent, based on the assumption that
most exposure to chloroform is likely to
come from ingestion of drinking water.
In the final Stage 1 DBPR, EPA
reconsidered this assumption in
response to comments and in the light
of data which indicate that exposure to
chloroform by inhalation and dermal
exposure may potentially contribute a
substantial percentage of the overall
exposure to chloroform depending on
the activity patterns of individuals
(USEPA 1998e) e.g., during showering,
bathing, swimming, boiling water,
clothes washing, and dishwashing.
There is also potential exposure to
chloroform by the dietary route. There
are uncertainties regarding other
possible highly exposed sub-
populations, e.g., swimmers, those who
use humidifiers, hot-tubs, and outdoor
misters, persons living near industrial
sources, people working in
laundromats, and persons working with
pesticides employing chloroform as a
solvent (USEPA 1998b).
A 1998 International Life Sciences
Institute (ILSI) report evaluated the
uptake of drinking water contaminants
through the skin and by inhalation. The
report noted that "(i)u the case of
chloroform, its high volatility leads to
its rapid movement from liquid to air.
Large water-use sources, such as
showers, become dominant sources with
respect to exposure" and "(t)he
inhalation route is demonstrated to be
the primary route for higher-volatility
compounds (e.g., chloroform)" (ILSI
1998). Weisel and Jo (1996) found that
"approximately equivalent amounts of
chloroform from water can enter the
body by three different exposure routes,
inhalation, dermal absorption, and
ingestion, for typical daily activities of
drinking and bathing."
Chloroform has been found in
beverages, especially soft drinks, and
food, particularly dairy products
(Wallace, 1997). Wallace states that
"ingestion (drinking tap water and soft
drinks and eating certain dairy foods),
inhalation (breathing peak amounts of
chloroform emitted during showers or
baths, and lower levels in indoor air
from other indoor sources), and dermal
absorption (during showers, baths, and
swimming)" each "appear to be
potentially substantial contributors to
total exposure".
EPA estimates that for the median
individual, ingestion of total tap water
(assuming certain activity patterns,
habits, and home characteristics) can
contribute roughly 28 percent of the
total dose of chloroform (USEPA 2001a).
With assumptions as described, tap
water ingestion is a portion of exposure
through fluid intake which contributes
about 34 percent of the total dose,
inhalation accounts for about 31 percent
of the total dose, ingestion of foods
contributes another 27 percent of the
overall dose, and dermal absorption
(primarily during showering) adds
slightly less than 8 percent of the total
dose. These exposure percentages are
based on average daily doses (mean
chloroform intake for adults) for each
source and route of exposure under
specific conditions. They do not take
into account the considerable variability
in several factors across the population.
For instance, intake of drinking water or
particular foods and length of shower
varies from day-to-day, as do home air
turnover rates and ventilation. Different
areas in the United States vary with
respect to these factors and chloroform
concentrations in food. Thus, although
the 28 percent for the median individual
is based on reasonable assumptions,
uncertainty remains.
Given the uncertainties of estimation,
EPA believes available analyses point to
the RSC of 20 percent as the appropriate
default (i.e., 20 percent of exposure to
chloroform comes from drinking tap
water alone). EPA also believes that this
default is protective of public health
and is a more reasonable choice than
choosing any particular estimate
because of the assumptions and
uncertainties involved with each
estimation. Hence, EPA is proposing the
MCLG based on the RSC default of 20
percent which supports the adequacy of
the margin of safety associated with the
MCLG.
iii. Water ingestion and body weight
assumptions. In MCLG calculations,
EPA assumes the 90th percentile water
ingestion of 2 liters (roughly equivalent
to a half gallon) per day (USEPA 2000a).
The use of a conservative consumption
estimate is consistent with the objective
of setting an MCLG that is protective.
EPA also uses a default adult body
weight of 70 kg (equal to 154 pounds)
for the RfD since dose is calculated from
lifetime studies of animals and
compared to lifetime exposure for
humans.
iv. MCLG calculation. The MCLG is
calculated to be 0.07 mg/L using the
following assumptions: an adult tap
water consumption of 2 L per day for a
70 kg adult, and a relative source
contribution of 20%:
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49579
x^.^.r ™ t O.Olmg/kg/dx 70kg x 0.2 nn_
MCLG for Chloroform = — = 0.07 mg/L (rounded)
2L/day
EPA concludes that an MCLG of 0.07
mg/L based on protection against liver
toxicity will be protective against
carcinogenicity given that the mode of
action for chloroform involves
cytotoxicity as a key event preceding
tumor development. Therefore, the
recommended MCLG for chloroform is
0.07 mg/L.
v. Other considerations. The evidence
supports similarity of potential response
in children and adults. The basic
biology of toxicity caused by cell
damage due to oxidative damage is
expected to be the same. There is
nothing about the incidence and
etiology of liver and kidney cancer in
children to indicate that they would be
inherently more sensitive to this mode
of action. Most importantly in this case,
children appear to be no different
quantitatively in ability to carry out the
oxidative metabolism step for the
induction of toxicity and cancer and
may, as fetuses, be less susceptible
(USEPA 1999c).
Some commenters on the March 1998
NODA were concerned that EPA did not
take drinking water epidemiology
studies into account in its evaluation of
chloroform risk. EPA believes that while
the epidemiologic evidence suggests
that chlorinated drinking water may be
associated with certain cancers and
reproductive, developmental effects
pertinent to the risk of disinfectant
byproduct mixtures, it does not provide
insight into the risk from chloroform
specifically. The SAB noted that "(t)he
goal of the draft risk assessment (the
isolation of the effect of chloroform in
drinking water) makes the extensive
epidemiologic evidence on drinking
water disinfection byproducts largely
irrelevant" to the specific question of
chloroform health risks because, in the
available studies, chloroform cannot be
isolated from other disinfection
byproducts that may be in the drinking
water (USEPA 2000f). The SAB noted
that "the epidemiologic evidence is
quite pertinent to the broader question
of most direct regulatory concern,
namely disinfection byproducts in the
aggregate".
d. Feasibility of other options. During
the development of the MCLG for
chloroform, EPA considered a number
of options for both the chloroform
MCLG and the TTHM MCL. Today, EPA
is proposing the preferred option of a
0.07 mg/L MCLG for chloroform. EPA
primarily considered two other options
which are discussed in more detail later:
a 0.07 mg/L MCLG for chloroform in
conjunction with developing MCLs for
each of the individual TTHMs [i.e., 4
MCLs and 4 MCLGs for the THMs); and
developing a single combined MCLG for
TTHM rather than developing a separate
MCLG for each of the THMs.
EPA considered developing separate
MCLGs and MCLs for each THM. Under
this strategy, EPA would determine an
MCL as close to the individual MCLGs
as is technically feasible, taking cost
into consideration, for each THM. EPA
would propose an MCLG of 0.07 mg/L
for chloroform and maintain the Stage 1
DBPR MCLGs for BDCM, DBCM, and
bromoform (USEPA 1998c). EPA
analyzed the impact such an MCL
strategy would have and ultimately
rejected this option. This approach
represents a fundamental shift from the
TTHM strategy agreed to by
stakeholders and EPA as part of the M—
DBF negotiation process and reflected in
the 1998 Stage 1 DBPR. In addition, one
important component of the existing
single MCL is that TTHMs are an
indicator for other DBFs. Developing a
separate MCL for each THM would
move away from this indicator
approach. Because precursor and DBF
occurrence measurements are highly
variable, both temporally and
geographically, determining technical
feasibility for best available technology
(BAT) would be difficult. Compliance
with individual THM standards would
be very different from compliance based
on a sum of the four THMs and it is not
clear what treatment technology shifts
would be needed. This problem would
be particularly exacerbated in areas with
high bromide, such as California. EPA
also projected that States would have a
difficult time overseeing (e.g., variances,
exemptions, etc.) the more complicated
rule that would result from this option.
EPA considered establishing a single
combined MCLG for TTHM. There is
precedent for using a toxicity
equivalency quotient (analogous to a
combined MCLG) for dioxin and
coplanar PCBs (USEFA 2000o, Draft
Dioxin Reassessment). From a scientific
standpoint, a combined MCLG approach
requires that the chemicals have a
similar mode of action and health
endpoint. Chemicals within each of the
dioxin and coplanar PCS classes have
the same mode of action and endpoint
(target tissue). Within the PCB class,
noncoplanar PCBs have a different
mode of action than the coplanar PCBs.
Noncoplanar PCBs are, therefore, not
included in the toxicity equivalency
quotient for coplanar PCBs. In the case
of the disinfection byproducts, EPA
believes that the THMs have different
modes of action and health endpoints.
One of the THMs is a liver carcinogen
(chloroform) with a mode of action
dependent on cytolethality; two are
DNA-reactive carcinogens
(bromodichloromethane—large intestine
and kidney tumors, and bromoform—
large intestine tumors); and one is a
nonlinear non-carcinogen
(dibromochloro me thane) which is a
liver toxicant. EPA therefore, chose not
to develop a combined MCLG for
TTHM. Consequently, after considering
this alternative option in some detail,
EPA is today proposing an MCLG of
0.07 mg/L for chloroform.
3. Request for Comment
Based on the information presented
previously, EPA is proposing an MCLG
for chloroform of 0.07 mg/L. EPA
requests comments on the MCLG and on
EPA's cancer assessment for chloroform.
EPA also requests comments on the RfD,
the default RSC of 20 percent, and the
tap water consumption and body weight
assumptions used in the MCLG
calculation. EPA solicits additional data
on chloroform exposure via other
sources and routes. EPA requests
comment on the other options for
developing the chloroform MCLG that
the Agency considered.
B. MCLGs for THMs and HAAs
1. What Is EPA Proposing Today?
Today EPA is proposing new MCLGs
of 0.02 mg/L for TCAA and 0.03 mg/L
for MCAA based on new toxicological
data. As a part of the Stage 1 DBPR, EPA
finalized an MCLG of 0.3 mg/L for
TCAA. The Stage 1 DBPR did not
include an MCLG for MCAA (although
it was included as one of the five
haloacetic acids in the HAAS MCL).
With the exception of chloroform,
discussed above, and these two HAAs,
EPA is not revising any of the other
MCLGs that were finalized in the Stage
1 DBPR. No significant new studies that
would change EPA's MCLG estimates
for BDCM, DBCM, bromoform, or DCAA
have been published since the Stage 1
DBPR. See section III for a summary of
new health effects data.
2. How Was This Proposal Developed?
EPA reviewed the available literature
on BDCM, DBCM, bromoform, DCAA
and determined that there was no new
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information that would cause EPA to
revise its MCLG estimates. New
toxicology studies on reproductive and
developmental effects and cancer are
summarized in sections III.B. and III.D.
of today's proposal.
EPA is proposing new MCLGs for
TCAA and MCAA. The health effects
information and studies described in the
following two sections that support the
proposed MCLGs are summarized from
the Addendum to the Criteria Document
for Monochloroacetic Acid and
Trichloroacetic Acid (USEPA 2003b).
The occurrence of MCAA and TCAA are
discussed in the Stage 2 Occurrence
Assessment for Disinfectants and
Disinfection Byproducts (USEPA
2003o). a, Trichloroacetic acid. In the
final Stage 1 DBPR, EPA based its health
effects assessment of TCAA on
developmental toxicity and limited
evidence of carcinogenicity (USEPA
1998c). Since then, the Agency has
decided that the RfD based on a
developmental LOAEL yields a less
conservative RfD than that based on
liver toxicity derived from the study by
DeAngelo et al. (1997). Thus, the
Agency has reassessed the health effects
of TCAA based on liver toxicity and
revised the RfD and MCLG.
TCAA induces systemic, noncancer
effects in animals and humans that can
be grouped into three categories:
metabolic alterations, liver toxicity; and
developmental toxicity. The primary
site of TCAA toxicity is the liver
(USEPA1994a; Dees and Travis, 1994;
Acharya et al. 1995; Acharya et al. 1997;
DeAngelo e(a/.1997).
The liver has consistently been
identified as a target organ for TCAA
toxicity in short-term (Goldsworthy and
Popp, 1987; DeAngelo et a!. 1989;
Sanchez and Bull, 1990) and longer-
term (Bull et al. 1990; Mather et al.
1990; Bhat et al. 1991) studies.
Peroxisome proliferation has been a
primary endpoint evaluated, with mice
reported to be more sensitive to this
effect than rats. More recent studies
have confirmed these earlier findings,
TCAA-induced peroxisome proliferation
was observed in B6C3F1 mice exposed
for 10 weeks to doses as low as 25 mg/
kg/day (Fairish et al. 1996), while in rats
exposed to TCAA for up to 104 weeks
(DeAngelo etal. 1997), peroxisome
proliferation was observed at 364 mg/
kg/day, but not at 32.5 mg/kg/day.
Increased liver weight and significant
increases in hepatocyte proliferation
have been observed in short-term
studies in mice at doses as low as 100
mg/kg/day (Dees and Travis, 1994), but
no increase in hepatocyte proliferation
was noted in rats given TCAA at similar
doses (DeAngelo etal 1997). More
clearly adverse liver toxicity endpoints,
including increased serum levels of
liver enzymes (indicating leakage from
cells) or histopathological evidence of
necrosis, have been reported in rats, but
generally only at high doses. For
example, in a rat chronic drinking water
study, increased hepatocyte necrosis
was observed at a dose of 364 mg/kg/
day (DeAngelo et al. 1997).
In the DeAngelo et a7.(1997) study,
groups of 50 male F344 rats were
administered TCAA in drinking water,
at 0, 50, 500, or 5000 mg/L, resulting in
time-weighted mean daily doses of 0,
3.6, 32.5, or 364 mg/kg for 104 weeks.
There were no significant differences in
water consumption or survival between
the control and treatment groups.
Exposure to the high dose of TCAA
resulted in a significant decrease in
body weight of 11 % at the end of the
study. The absolute but not relative liver
weight was decreased at the high dose.
Complete necropsy and histopathology
examination showed mild hepatic
cytoplasmic vacuolization in the two
low-dose groups, but not in the high-
dose group. The severity of hepatic
necrosis was increased mildly in the
high-dose animals. Analyses of serum
aspartate aminotransferase (AST) and
alanine aminotransferase (ALT)
activities at the end of exposure showed
a significant decrease in AST activity in
the mid-dose group and a significant
increase in ALT level in the high-dose
group. Since increased serum ALT or
AST levels reflect hepatocellular
necrosis, the increased ALT at the high
dose is considered an adverse effect,
while a non-dose related decrease of
AST is not. Peroxisome proliferation
was increased significantly in the high-
dose animals. There was no evidence of
any exposure-related increase in
hepatocyte proliferation. Based on the
significant decrease in body weight
(>10%), minimal histopathology
changes, and increased serum ALT
level, the high dose of 364 mg/kg/day is
considered the LOAEL and the mid dose
of 32.5 mg/kg/day is considered the
NOAEL.
There are no reproductive toxicity
studies of TCAA. The results of an in
vitro fertilization assay indicated that
TCAA might decrease fertilization
(Cosby and Dukelow, 1992). The
available data suggest that TCAA is a
developmental toxicant. TCAA
increased resorptions, decreased
implantations, and increased fetal
cardiovascular malformations when ,
administered to pregnant rats at 291 mg/
kg/day (Johnson et al 1998) on gestation
days 1-22. In another study, decreased
fetal weight and length, and increased
cardiovascular malformations were
observed when pregnant rats were
administered 330 mg/kg/day TCAA by
gavage during gestation days 6 to 15
(Smith et al 1989). Neither of these
studies identified a NOAEL. The results
of in vitro developmental toxicity
assays, including mouse and rat whole-
embryo culture (Saillenfait et al. 1995;
Hunter et al 1996) and frog embryo
teratogenesis assay—Xenopus (FETAX)
(Fort et al 1993) yielded positive
results. The Hydra test system (Fu el al
1990) produced negative results.
TCAA has been reported to induce
liver tumors in mice but not in rats
(USEPA 1994a). This observation has
also been made in more recent drinking
water studies, Pereira (1996) observed
an increased incidence of hepatocellular
adenomas and carcinomas in female
B6C3F1 mice at doses of 262 mg/kg/day
and higher after 82 weeks. In contrast,
no. increase in neoplastic liver lesions
were found in F344 rats given doses up
to 364 mg/kg/day for 104 weeks
(DeAngelo et al 1997). In addition, a
variety of recent mechanistic studies
have observed that TCAA either
induced or promoted liver tumors in
mice (Ferreira-Gonzalez et al 1995;
Pereira and Phelps, 1996; Tao et al
1996; Latendresse and Pereira, 1997;
Stauber and Bull, 1997; Tao et al 1998).
Recent mutagenicity data have
provided mixed results (Ciller et al
1997; DeMarini et al 1994; Harrington-
Brock et al 1998). TCAA did not induce
oxidative DNA damage in mice
following dosing for either 3 or 10
weeks (Parrish et al 1996). Studies on
DNA strand breaks and chromosome
damage produced mixed results (Nelson
and Bull, 1988; Chang et al 1991;
Mackay et al 1995; Harrington-Brock et
al 1998).
According to the 1999 Draft
Guidelines for Carcinogen Risk
Assessment (USEPA 1999a), a
compound is appropriately classified as
"Suggestive Evidence of
Carcinogenicity, but Not Sufficient to
Assess Human Carcinogenic Potential"
when "the evidence from human or
animal data is suggestive of
carcinogenicity, which raises a concern
for carcinogenic effects but is judged not
sufficient for a conclusion as to human
carcinogenic potential". Based on
uncertainty surrounding the relevance
of the liver tumor data in B6C3F1 mice,
TCAA can best be described as
"Suggestive Evidence of
Carcinogenicity, but Not Sufficient to
Assess Human Carcinogenic Potential"
under the 1999 Draft Guidelines for
Carcinogen Risk Assessment. Thus a
quantitative estimate of cancer potency
is not supported.
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49581
The RfD for TCAA of 0.03 mg/kg/day
is based on the NOAEL of 32.5 mg/kg/
day for liver histopathological changes
identified by DeAnge3o et al (1997).
The RfD includes an uncertainty factor
of 1000 (composite uncertainty factor
consisting of three factors of 10 chosen
to account for extrapolation from a
NOAEL in animals, inter-individual
variability in humans, and
insufficiencies in the database,
including the lack of full
histopathological data in a second
species, the lack of a developmental
toxicity study in second species, and the
lack of a multi-generation reproductive
study).
The MCLG is calculated to be 0.02
mg/L using the following assumptions:
an adult tap water consumption of 2 L
of tap water per day for a 70 kg adult,
a relative source contribution (RSC) of
20%, and an additional safety factor to
account for possible carcinogen!city.
EPA has traditionally applied an
additional safety factor of 1-10 beyond
the uncertainty factors included in the
RfD to the MCLG to account for possible
carcinogenicity in cases where there is
limited evidence of carcinogenicity from
drinking water, considering weight of
evidence, pharmacokinetics, potency
and exposure (USEPA 1994b, p.38678).
EPA is proposing this additional safety
factor of 10 for TCAA for the following
reasons: TCAA causes liver tumors in
mice but does not do so in rats. In
addition, although peroxisome
proliferation (a mode of action of
limited relevance to humans) may play
a role in the development of the mouse
tumors, rats also exhibit a peroxisomal
proliferative response after exposure to
TCA, yet do not develop tumors. Other
data suggest that promotion of initiated
cells and/or disrupted cell signaling
may be involved in the mode of action
for the mouse tumors. Together these
factors argue against quantification of
the mouse liver tumors using linear
extrapolation from the dose-response
curve, but are not sufficient to rule out
concern for a tumorigenic response.
Accordingly, EPA has employed the ten-
fold additional safety factor in
determination of the Lifetime Health
Advisory for TCAA. EPA requests
comment on the use of 10 as the
additional safety factor for possible
carcinogenicity.
MCLG for TCAA =
(0'°3
(2 L/day)(10)
= 0.02 mg/L (rounded)
An RSC factor of 20% is used to
account for exposure to TCAA in
sources other than tap water, such as
ambient air and food. Although TCAA
is nonvolatile and inhalation while
showering is not expected to be a major
contribution to total dose, rain waters
contain 0.01-1.0 ug/L of TCAA
(Reimann et al. 1996} and it can be
assumed to be detected in the
atmosphere. Limited data on
concentrations of TCAA in air (NATICH
1993) indicate inhalation of TCAA in
ambient air may contribute to overall
exposure. Concentrations of TCAA that
have been measured in a limited
selection of foods including vegetables,
fruits, grain and bread (Reimann et al.
1996) are comparable to that in water.
About 3 to 33% of TCAA in cooking
water have been reported to be taken up
by the food during cooking in a recent
research summary (Raymer et al. 2001).
In addition, there are uses of chlorine in
food production and processing, and
TCAA may occur in food as a byproduct
of chlorination (USEPA 1994a).
Therefore, ingestion of TCAA in food
may also contribute to the overall
exposure. A recent dermal absorption
study of DCAA and TCAA from
chlorinated water suggested that the
dermal contribution to the total doses of
DCAA and TCAA from routine
household uses of drinking water is less
than 1% (Kim and Weisel, 1998).
b. Monochloroacetic acid. Subchronic
and chronic oral dosing studies suggest
that the primary targets for MCAA-
induced toxicity include the heart and
nasal epithelium. In a 13-week oral
savage study, decreased heart weight
was observed at 30 mg/kg/day and
cardiac lesions progressed in severity
with increasing dose. Liver and kidney
toxicity were only observed at higher
doses (NTP 1992). In a two-year study,
decreased survival and nasal and
forestomach hyperplasia were observed
in mice at 50 mg/kg/day (NTP 1992). A
more recent study confirms the heart
and nasal cavities as target sites for
MCAA. DeAngelo et al. (1997) noted
decreased body weight at 26.1 mg/kg/
day and myocardial degeneration and
inflammation of the nasal cavities in
rats exposed to doses of 59.9 mg/kg/day
for up to 104 weeks.
No studies were located on the
reproductive toxicity of MCAA and the
potential developmental toxicity of
MCAA has not been adequately tested.
Two developmental toxicity studies
were identified. Johnson et al. (1998)
reported markedly decreased maternal
weight gain, but no developmental
effects, in rats exposed to 193 mg/kg/
day MCAA through gestation days 1-22,
only fetal heart was examined. In
contrast, in a published abstract, Smith
et al. (1990) reported an increase in
cardiovascular malformations when
pregnant rats were exposed to 140 mg/
kg/day; this was also the LOAEL for
-maternal toxicity, based on marked
decreases in weight gain. MCAA was
noted as a potential developmental
toxicant in in vitro screening assays
using Hydra (Fu et al. 1990; Ji et al.
1998).
MCAA has yielded mixed results in
genotoxicity assays (USEPA 1994a;
Ciller et al. 1997), but has not induced
a carcinogenic response in chronic
rodent bioassays (NTP 1992; DeAngelo
et al. 1997). In chronic oral gavage
studies, a LOAEL of 15 mg/kg/day (the
lowest dose tested) for decreased
survival was identified in rats. In mice
the NOAEL was 50 mg/kg/day and the
LOAEL was 100 mg/kg/day for nasal
and forestomach epithelium hyperplasia
(NTP 1992). In a more recent chronic
study, DeAngelo et al. (1997) reported a
LOAEL of 3.5 mg/kg/day in rats given
MCAA in their drinking water, based on
increased absolute and relative spleen
weight. Although spleen weight was
decreased at the mid and high doses,
this might reflect the masking effect of
overt toxicity. As evidence for this,
decreased body weight (>10%), liver,
kidney, and testes weight changes were
reported beginning at the next higher
dose of 26.1 mg/kg/day. No increased
spleen weight was reported in the NTP
(1992) bioassays, but the lowest dose in
rats caused severe toxicity, and the
lowest dose in mice was more than an
order of magnitude higher than the
LOAEL in the DeAngelo et al. (1997)
study.
According to the 1999 Draft
Guidelines for Carcinogen Risk
Assessment (USEPA 1999a), a
compound is appropriately classified as
"Not Likely to be Carcinogenic to
Humans" when it has "been evaluated
in at least two well-conducted studies in
two appropriate animal species without
demonstrating carcinogenic effects."
MCAA can best be described as "Not
Likely to be Carcinogenic to Humans"
under the 1999 Draft Guidelines for
Carcinogen Risk Assessment.
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The RfD for MCAA of 0.004 mg/kg/
day is based on a LOAEL of 3.5 mg/kg/
day for increased spleen weight in rats
(DeAngelo et al. 1997) and application
of an uncertainty factor of 1000
(composite uncertainty factor consisting
of two factors of 10 chosen to account
for extrapolation from an animal study,
and inter-individual variability in
humans; as well as two factors of 3 for
extrapolation from a minimal effect
LOAEL, and insufficiencies in the
database, including the lack of adequate
developmental toxicity studies in two
species, and the lack of a multi-
generation reproductive study). Two
developmental toxicity studies have
been reported (Johnson et al. 1998;
Smith et al. 1990), but the NOAELs
yielded less conservative RfDs. The
study by DeAngelo et al (1997) is the
most appropriate for derivation of the
RfD because it identifies the lowest
LOAEL, and dosing was in drinking
water, which is more appropriate for
human health risk assessment.
The MCLG is calculated to be 0,03
mg/L using the following assumptions:
an adult tap water consumption of 2 L
of tap water per day for a 70 kg adult,
and a relative source contribution of
20%.
wnr H*-AA (0.004 mg/kg/day)(70 kg)(20%) ...
MCLG for MCAA = —-—— ~ = 0.03 mg/L (rounded)
(2 L/day)
An RSC factor of 20% is used to
account for exposure to MCAA in other
sources in addition to tap water.
Although MCAA is nonvolatile and
inhalation while showering is not
expected to be a major contribution to
total dose, rain waters contain 0.05-9
ug/L of MCAA (Reimann et al. 1996)
and it can be assumed to be detected in
the atmosphere. Presence of MCAA has
also been reported in rain waters; thus,
inhalation of MCAA in ambient air may
contribute to overall exposure.
Concentrations of MCAA that have been
measured in a limited selection of foods
including vegetables, fruits, grain and
bread (Reimann et al, 1996) are
comparable to that in water. About 2.5
to 62% of MCAA in cooking water has
been reported to be taken up by food
during cooking in a recent research
summary (Raymer et al. 2001). In
addition, there are uses of chlorine in
food production and processing, and
MCAA may occur in food as a
byproduct of chlorination (USEPA
1994a). Therefore, ingestion of MCAA in
food may also contribute to the overall
exposure. Assuming dermal absorption
rate of MCAA is similar to DCAA,
dermal contribution to the total doses of
MCAA from routine household uses of
drinking water should be minor (see
V.B.2.B.).
3. Request for Comment
EPA requests comment on the new
MCLGs for TCAA (0.02 mg/L) and
MCAA (0.03 mg/L) and all the factors
incorporated in the derivation of the
MCLGs, including the RfDs and RSCs.
EPA also solicits health effect
information on DBAA and
monobromoacetic acid (MBAA), for
which MCLGs have not yet been
established.
C. Consecutive Systems
Today's proposal includes provisions
for consecutive systems, which are
public water systems that purchase or
otherwise receive finished water from
another water system (a wholesale
system). As described in this section,
consecutive systems face particular
challenges in providing water that meets
regulatory standards for DBFs and other
contaminants whose concentration can
increase in the distribution system.
Moreover, current regulation of DBF
levels in consecutive systems varies
widely among States. In consideration
of these factors, EPA is proposing
monitoring, compliance schedule, and
other requirements specifically for
consecutive systems. These
requirements are intended to facilitate
compliance by consecutive systems
with MCLs for TTHM and HAA5 under
the Stage 2 DBPR. Further, this
approach will help to ensure that
consumers in consecutive systems
receive equivalent public health
protection. This section begins with a
summary of how EPA proposes to
regulate consecutive systems under the
Stage 2 DBPR. The intent of this section
is to provide an overview of all
consecutive system requirements in
today's proposal. Detailed explanations
of these requirements are provided in
later sections of this preamble. The
overview of consecutive system
requirements is followed by an
explanation of why EPA has taken this
approach to consecutive systems in
today's proposal, including
recommendations from the Stage 2 M-
DBP Federal Advisory Committee.
1. What Is EPA Proposing Today?
As public water systems, consecutive
systems must provide water that meets
the MCLs for TTHM and HAA5 under
the proposed Stage 2 DBPR, and must
carry out associated monitoring,
reporting, recordkeeping, public
notification, and other requirements.
The following discussion summarizes
how the Stage 2 DBPR requirements
apply to consecutive systems, beginning
with a series of definitions. Later
sections of this preamble provide
further details as noted.
a. Definitions. To address consecutive
systems in the Stage 2 DBPR, the
Agency must define them, along with a
number of related terms.
EPA is proposing to define a
consecutive system in the Stage 2 DBPR
as a public water system that buys or
otherwise receives some or all of its
finished water from one or more
wholesale systems for at least 60 days
per year. In addition to buying finished
water, some consecutive systems also
operate a treatment plant (meaning a
plant that treats source water to produce
finished water). As described in section
V.I., monitoring requirements under the
Stage 2 DBPR proposal differ depending
on whether a consecutive system buys
all of its finished water year-round or,
alternatively, produces some of its
finished water through treating source
water.
EPA proposes to define finished water
as water that has been introduced into
the distribution system of a public water
system and is intended for distribution
without further treatment, except that
necessary to maintain water quality
(such as booster disinfection). With this
definition, water entering the
distribution system is finished water
even if a system subsequently applies
additional treatment like booster
disinfection to maintain a disinfectant
residua] throughout the distribution
system.
In today's proposal, EPA defines a
wholesale system as a public water
system that treats source water and then
sells or otherwise delivers finished
water to another public water system for
at least 60 days per year. Delivery may
be through a direct connection or
through the distribution system of
another consecutive system. Under this
definition, a consecutive system that
passes water from a wholesaler to
another consecutive system, and that
does not also treat source water, is not
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49583
wholesale system. Rather, the system
hat actually produces the finished
vater is responsible for wholesale
ystem requirements under the
iroposed Stage 2 DBPR.
A consecutive system entry point is
lefined as a location at which finished
vater is delivered at least 60 days per
ear from a wholesale system to a
:onsecutive system. Section V.I.
iresents the relationship between
onsecutive system entry points and
>roposed Stage 2 DBPR monitoring
equirements. The combined
Distribution system is the
interconnected distribution system
onsisting of the distribution systems of
vholesale systems and of the
onsecutive systems that receive
inished water from those wholesale
ystem(s).
b. Monitoring. For consecutive
ystems that both purchase finished
Lvater and treat source water to produce
inished water for at least part of the
ear, EPA is proposing monitoring
equirements under a treatment plant-
ased approach, described in section
V.I. This is the approach proposed for
on-consecutive systems under the
tage 2 DBPR as well. Under this
pproach, the sampling requirements for
onsecutive systems will be influenced
y both the number of treatment plants
perated by the system and the number
f consecutive system entry points, as
l as population served and source
.vater type.
For consecutive systems that purchase
II of their finished water year-round,
PA is proposing monitoring
jquirements under a population-based
pproach, also described in section V.I.
;nder the population-based approach,
population of the consecutive
ystem will determine the sampling
iquirements. EPA believes this
pproach is more appropriate than
lant-based monitoring because these
onsecutive systems do not have
reatment plants. As noted in section
.1., EPA is requesting comment on
xtending population-based monitoring
o all systems, including non-
onsecutive systems. EPA has prepared
raft guidance for implementing the
DSE monitoring requirements
described in section V.H.) using the
opulation-based approach (USEPA
003j).
EPA is also proposing that States have
le opportunity to specify alternative
nonitoring requirements for multiple
onsecutive systems in a combined
istribution system. This option allows
tates to consider complex consecutive
ystem configurations for which
ternative monitoring strategies might
e more appropriate. As a minimum
under such an approach, each
consecutive system must collect at least
one sample among the total number of
samples required for the combined
distribution system and will base
compliance on samples collected within
its distribution system. The consecutive
system is responsible for ensuring that
required monitoring is completed and
the system is in compliance. The
consecutive system may conduct the
monitoring itself or arrange for the
monitoring to be done by the wholesale
system or another outside party.
Whatever approach it chooses, the
consecutive system must document its
monitoring strategy as part of its DBP
monitoring plan.
Finally, EPA is proposing that
consecutive systems not conducting
disinfectant residual monitoring comply
with the monitoring requirements and
MRDLs for chlorine and chloramines.
c. Compliance schedules. EPA is
proposing that consecutive systems of
any size comply with the requirements
of the Stage 2 DBPR on the same
schedule as required for the largest
system in the combined distribution
system. This includes the schedule for
carrying out the IDSE, described in
section V.H, and for meeting the Stage
2B MCLs for TTHM and HAA5,
described in section V.D. As discussed
later in this section, EPA is proposing
simultaneous compliance schedules
under the Stage 2 DBPR for all systems
(both wholesalers and consecutive
systems) in a combined distribution
system because this may allow for more
cost-effective compliance with TTHM
and HAA5 MCLs. This is also consistent
with the recommendations of the Stage
2 M-DBP Advisory Committee. See
section V.J for details of compliance
schedule requirements.
d. Treatment. While consecutive
systems often do not need to treat
finished water received from a
wholesale system, they may need to
implement procedures to control the
formation of DBFs in the distribution
system. For consecutive systems, EPA is
proposing that the BAT for meeting
TTHM and HAAS MCLs is
chloramination with management of
hydraulic flow and storage to minimize
residence time in the distribution
system. This BAT stems from the
recognition that treatment to remove
already-formed DBFs or minimize
further formation is different from
treatment to prevent or reduce their
formation. See section V.F for additional
information on BATs and their role in
compliance with MCLs.
e. Violations. Under this proposal,
monitoring and MCL violations are
assigned to the PWS where the violation
occurred. Several examples are as
follows:
—If a consecutive system has hired its
wholesale system under contract to
monitor in the consecutive system
and the wholesale system fails to
monitor, the consecutive system is in
violation because it has the legal
responsibility for monitoring under
State/EPA regulations.
—If monitoring results in a consecutive
system indicate an MCL violation, the
consecutive systems is in violation
because it has the legal responsibility
for complying with the MCL under
State/EPA regulations. The
consecutive system may set up a
contract with its wholesale system
that details water quality delivery
specifications.
—If a wholesale system has a violation
and provides that water to a
consecutive system, the wholesale
system is in violation. Whether the
consecutive system is in violation will
depend on the situation. The
consecutive system will also be in
violation unless it conducted
monitoring that showed that the
violation was not present in the
consecutive system.
f. Public notice and consumer
confidence reports. The responsibilities
for public notification and consumer
confidence reports rest with the
individual system. Under the Public
Notice Rule and Consumer Confidence
Report Rule, the wholesale system is
responsible for notifying the
consecutive system of analytical results
and violations related to monitoring
conducted by the wholesale system.
Consecutive systems are required to
conduct appropriate public notification
after a violation (whether in the
wholesale system or the consecutive
system). In their consumer confidence
report, consecutive systems must
include results of the testing conducted
by the wholesale system unless the
consecutive system conducted
equivalent testing that indicated the
consecutive system was in compliance,
in which case the consecutive system
reports its own compliance monitoring
results.
g. Recordkeeping and reporting.
Consecutive systems are required to
keep all records required of PWSs
regulated under this rule. They are also
required to report to the State
monitoring results, violations, and other
actions,.and are required to consult with
the State after a significant excursion.
h. State special primacy conditions.
EPA is aware that due to the
complicated wholesale system-
consecutive system relationships that
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exist nationally, there will be cases
where the standard monitoring
framework proposed today will be
difficult to implement. Therefore, the
Agency is proposing to allow States to
develop, as a special primacy condition,
a program under which the State can
modify monitoring requirements for
consecutive systems. These
modifications must not undermine
public health protection and all
systems, including consecutive systems,
must comply with the TTHM and HAAS
MCLs based on the LRAA. However,
such a program would allow the State
to establish monitoring requirements
that account for complicated
distribution system relationships, such
as where neighboring systems buy from
and sell to each other regularly
throughout the year, water passes
through multiple consecutive systems
before it reaches a user, or a large group
of interconnected systems have a
complicated combined distribution
system. EPA intends to develop a
guidance manual to address
development of a State program and
other consecutive system issues.
2. How Was This Proposal Developed?
The practice of public water systems
buying and selling water to each other
has been commonplace for many years.
Reasons include saving money on
pumping, treatment, equipment, and
personnel; assuring an adequate supply
during peak demand periods; acquiring
emergency supplies; selling surplus
supplies; delivering a better product to
consumers; and meeting Federal and
State water quality standards. EPA
estimates that there are at least 8500
consecutive systems nationally, based
on the definitions being proposed today.
Consecutive systems face particular
challenges in providing water that meets
regulatory standards for contaminants
that can increase in the distribution
system. Examples of such contaminants
include coliforms, which can grow if
favorable conditions exist, and some
DBFs, including THMs and HAAs,
which can increase when a disinfectant
and DBP precursors continue to react in
the distribution system.
EPA is proposing requirements
specifically for consecutive systems
because States have taken widely
varying approaches to regulating DBFs
in consecutive systems. For example,
some States do not regulate DBP levels
in consecutive systems that deliver
disinfected water but do not add a
disinfectant. Other States determine
compliance with DBP standards based
on the combined distribution system
that includes both the wholesaler and
consecutive systems. In this case, sites
in consecutive systems are treated as
monitoring sites within the combined
distribution system. Once fully
implemented, this proposed rule will
ensure similar protection for consumers
in consecutive systems.
EPA is proposing that consecutive
systems and wholesale systems be on
the same compliance schedule because
generally the most cost-effective way to
achieve compliance with TTHM and
HAAS MCLs is to treat at the source,
typically through precursor removal or
alternative disinfectants. For a
wholesale system to make the best
decisions concerning the treatment
steps necessary to meet TTHM and
HAAS LRAAs under the Stage 2 DBPR,
both in its own distribution system and
in the distribution systems of
consecutive systems it serves, the
wholesale system must know the DBP
levels throughout the combined
distribution system. Without this
information, the wholesale system may
design treatment changes that allow the
wholesale system to achieve
compliance, but leave the consecutive
system out of compliance. EPA also
recognizes that there may be cases
where a consecutive system needs to
add treatment even after a wholesale
system has optimized its own treatment
train.
In consideration of these issues, the
Stage 2 M-DBP Advisory Committee
recognized two principles related to
consecutive systems: (1) Consumers in
consecutive systems should be just as
well protected as customers of all
systems, and (2) monitoring provisions
should be tailored to meet the first
principle. Accordingly, the Advisory
Committee recommended that all
wholesale and consecutive systems
comply with provisions of the Stage 2
DBPR on the same schedule required of
the wholesale or consecutive system
serving the largest population in the
combined distribution system. In
addition, the Advisory Committee
recommended that EPA solicit
comments on issues related to
consecutive systems that the Advisory
Committee had not fully explored
(USEPA 2000g). EPA agrees with these
recommendations and they are reflected
in today's proposal.
3. Request for Comment
EPA requests comment on all
consecutive system issues related to this
rule. Specifically, EPA requests
comment on the following:
—Whether the proposed definitions
adequately address various wholesale
system-consecutive system
relationships and issues.
—Whether any additional terms need to
be defined and, if so, what the
definition should be.
—Whether the criteria for States' use of
the special primacy criteria and other
State responsibilities are appropriate
and adequate.
—Whether it is necessary to require that
consecutive system treatment be
installed on the same compliance
schedule as the wholesale system in
cases where the size of the
consecutive system might otherwise
allow it a longer compliance time
frame and the consecutive system
treatment does not affect water quality
in any other system.
D. MCLs for TTHM and HAAS
1. What Is EPA Proposing Today?
Today, EPA is proposing use of
locational running annual averages
(LRAAs) to determine compliance with
the MCLs for TTHM and HAAS.
Consistent with the Stage 2 M-DBP
Advisory Committee recommendation,
EPA is proposing a phased approach for
LRAA implementation to allow systems
to identify compliance monitoring
locations for Stage 2B while facilitating
transition to the new compliance
strategy and maintaining simultaneous
compliance schedules for the Stage 2
DBPR and the LT2ESWTR.
In Stage 2A, all systems must comply
with MCLs of 0.120 mg/L for TTHM and
0.100 mg/L for HAAS as LRAAs using
Stage 1 DBPR compliance monitoring
sites. In addition, during this time
period, all systems must continue to
comply with the Stage 1 DBPR MCLs of
0,080 mg/L TTHM and 0.060 mg/L
HAAS as RAAs.
In Stage 2B, all systems, including
consecutive systems, must comply with
MCLs of 0.080 mg/L TTHM and 0.060
mg/L HAAS as LRAAs using sampling
sites identified under the Initial
Distribution System Evaluation (IDSE)
(discussed in section V.H.).
Details of proposed monitoring
requirements and compliance schedules
are discussed in preamble sections V.I.
and V.J., respectively, and may be found
in §141.136 and subpart V of today's
rule.
2. How Was This Proposal Developed?
a. Definition of an LRAA. The primary
objective of the LRAA is to reduce
exposure to high DBP levels. For an
LRAA, an annual average must be
computed at each monitoring site. The
RAA compliance basis of the 1979
TTHM rule and the Stage 1 DBPR allows
a system-wide annual average under
which high DBP concentrations in one
or more locations are averaged with, and
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49585
dampened by, lower concentrations calculating compliance with the MCLs RAA, and the proposed Stage 2 DBPR
slsewhere in the distribution system. for TTHM between a Stage 1 DBPR LRAA.
Figure V—1 illustrates the difference in BILLING CODE eseo-so-p
Figure V-l. Comparison of RAA and LRAA compliance calculations1.
Stage 1 DBPR
First Quarter
Distribution System
Sampling Location
Second Quarter
Third Quarter
Fourth Quarter
Average of All Samples Average of All Samples Average of All Samples Average of Alt Samples
Y '
Running Annual Average of Quarterly Averages
MUST BE BELOW MCL
Stage 2 DBPR
First Quarter
Second Quarter
Third Quarter
Fourth Quarter
First Quarter
Second Quarter
Third Quarter
Fourth Quarter
LRAA J
MUST BE BELOW MCL
First Quarter •
Second Quarter 9 !
Third Quarter • f LRAA 3
Fourth Quarter* I MUST BE BELOW MCL
First Quarter A
Second Quarter A
Third Quarter A ,
Fourth Quarter A J MUST BE BELOW MCL
>
LRAA 2
First Quarter
Second Quarter
Third Quarter
Fourth Quarter
LRAA 4
MUST BE BELOW MCL
TStage 2 DBPR sampling locations will be selected based on the results of an IDSE study and may occur at locations
different from Stage 1 DBPR sampling sites.
IILUNG CODE 6560-50-P
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b. Consideration of regulatory
alternatives. This section will discuss
EPA's and the Stage 2 M-DBP Advisory
Committee's decision-making process as
an array of alternative MGL strategies
were considered. EPA believes that the
MCL alternative proposed today (MCLs
of 0.080 mg/L TTHM, 0.060 mg/L HAA5
as LRAAs) is supported by the best
available research, data, and analysis.
The science related to cancer and
reproductive and developmental health
effects that may be associated with
DBPs, in conjunction with occurrence
data that show that a significant number
of high DBF levels occur under current
regulatory scenarios, justify a change in
regulation. EPA believes that this
proposal achieves an appropriate
balance between the available science
and the uncertainties. EPA believes that
regulatory action is necessary and
prudent in the interest of further public
health protection and that the LRAA
alternative in combination with the
IDSE is a balanced and reasonable
approach. Although it will not remove
all DBP peaks (individual samples with
values greater than the MCL), this
proposed regulation will ensure that
DBP exposures across a system's
distribution system are further reduced,
are more equitable, and may reduce
cancer and reproductive and
developmental risk.
The Advisory Committee discussions
primarily focused on the relative
magnitude of exposure reduction versus
the expected impact on the water
industry and its customers. Initially,
this analysis compared expected
reductions in DBP levels and
predictions of treatment technology
changes associated with a wide variety
of Stage 2 DBPR MCL alternatives.
After initial discussions, EPA and the
Advisory Committee primarily focused
on four types of alternative rule
scenarios.
Preferred Alternative.—MCLs of 0.080
mg/L TTHM and 0.060 mg/L HAAS as
LRAAs. Bromate MCL of 0.010 mg/L.
Alternative 1.—MCLs of 0.080 mg/L
TTHM and 0.060 mg/L HAAS as
LRAAs. Bromate MCL of 0.005 mg/L.
Alternative 2.—MCLs of 0.080 mg/L
TTHM and 0.060 mg/L HAAS as
individual sample maximums (i.e., no
single sample could exceed the MCL}.
Bromate MCL of 0.010 mg/L.
Alternative 3.—MCLs of 0.040 mg/L
TTHM and 0.030 mg/L HAAS as
RAAs. Bromate MCL of 0.010 mg/L.
EPA and the Advisory Committee,
with assistance from the Technical
Workgroup, conducted an in-depth
analysis of these regulatory alternatives.
In the process of evaluating alternatives,
EPA and the Advisory Committee
reviewed vast quantities of data and
many analyses that addressed health
effects, DBP occurrence, predicted
reductions in DBP levels, predicted
technology changes, and capital, annual,
and household costs. Details of the
compliance, occurrence, and cost
forecasts for the four alternative rule
scenarios are described in the Stage 2
DBPR Economic Analysis (EA) (USEPA
2003i) and the Stage 2 DBPR Occurrence
Document (USEPA 2003o).
In the end, the Advisory Committee
recommended the Preferred Alternative
in combination with the IDSE which
they believed would reduce exposure to
high levels of DBPs. Today, EPA is
proposing the Preferred Alternative in
combination with the IDSE.
The only difference between the
Preferred Alternative and Alternative 1
is the bromate MCL. The Advisory
Committee's recommendation to
maintain the Stage 1 DBPR bromate
MCL of 0,010 mg/L is discussed in
section V.G. of today's proposal.
Alternatives 2 and 3 are significantly
more stringent than the Stage 1 DBPR
with respect to the TTHM and HAAS
requirements. Alternative 2 would
require that all samples be below the
MCL. Because DBP occurrence is
variable across the distribution system
and over time (as discussed in section
IV), systems would have to base their
disinfectant and treatment strategies on
controlling their highest DBP
occurrence levels. Alternative 3
maintains the Stage 1 DBPR RAA
compliance calculation, but reduces the
Stage 1 DBPR MCLs by 50 percent. Both
alternatives 2 and 3 would cause
significant changes in treatment for a
large number of systems. The estimated
costs for Alternatives 2 and 3 are
approximately an order of magnitude
above the costs for the Preferred
Alternative (see section VII.B.).
Consistent with this greater stringency
of alternatives 2 arid 3, the predicted
DBP reductions and the resulting health
benefits for them are greater than those
predicted for the Preferred Alternative.
Although all members of the Advisory
Committee believed that the science
showing reproductive and
developmental health effects that have
been associated with DBPs was
sufficient to cause concern and warrant
regulatory action, the Advisory
Committee did not believe that the
association was certain enough to justify
the substantial change in treatment
technologies that would be required to
meet these alternatives. Thus, the
Advisory Committee rejected
Alternatives 2 and 3.
c. Basis for the LRAA. This section
discusses the data and information EPA
used to determine that the LRAA is an
appropriate compliance strategy for
today's proposed rule. EPA has chosen
compliance based on an LRAA due to
concerns about levels of DBPs above the
MCL in some portions of the
distribution system. The LRAA standard
will eliminate system-wide averaging.
The individuals served in areas of the
distribution system with above average
DBP occurrence levels masked by
averaging under an RAA are not
receiving the same level of health
protection. Although an LRAA standard
still allows averaging at a single location
over an annual period, EPA believes
that changing the basis of compliance
from an RAA to an LRAA will result in
decreased exposure to above average
DBP levels (see section VILA, for
predictions of DBP reductions under the
LRAA MCLs). This conclusion is based
on three considerations:
(1) There is considerable evidence
that under the current RAA MCL
compliance monitoring requirements a
small but significant proportion of
monitoring locations experience high
DBP levels. As summarized in section
IV of this preamble, 14 and 21% of
Information Collection Rule systems
currently meeting the Stage 1 DBPR
RAA MCLs had TTHM and HAAS single
sample concentrations greater than the
Stage I MCLs and ranged up to 140 ug/
L and 130 ug/L respectively (Figures IV-
1 and IV-2), though most of these
exceedences were below 100 ug/L.
(2) In some situations, the populations
served by certain portions of the
distribution system consistently receive
water that exceeds the MCL even though
the system is in compliance. As
discussed in section IV of this preamble,
some Information Collection Rule
systems meeting the Stage 1 DBPR RAA
MCLs had monitoring locations that
exceeded 0.080 mg/L TTHM and/or
0.060 mg/L HAAS as an annual average
(i.e., as LRAAs) by up to 25% (Figures
W-3 and IV-4). Five percent of plants
that achieved compliance with the Stage
1 TTHM MCL of 0.080 mg/L based on
an RAA had a particular sampling
location that exceeded 0.080 mg/L as an
LRAA (Figure IV-3). Figure IV-4 shows
similar results based on Information
Collection Rule HAAS data. Three
percent of plants that met the Stage 1
HAAS MCL of 0.060 mg/L as an RAA
had a.sampling location that exceeded -
0.060 mg/L as an LRAA. Customers
served at these locations consistently
received water with TTHM and/or
HAAS concentrations higher than the
system-wide MCL.
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(3) Compliance based on an LRAA
will remove the opportunity for systems
to average out samples from high and
low quality water sources. Some
systems are able to comply with an RAA
MCL even if they have a plant with a
poor quality water source (that thus
produces high concentrations of DBFs)
because they have another plant that has
a better quality water source (and thus
lower concentrations of DBFs).
Individuals served by the plant with the
poor quality source will usually have
higher DBF exposure than individuals
served by the other plant.
d. Basis for phasing LRAA
compliance. EPA believes that a phased
approach for LRAA implementation will
facilitate transition to the new
compliance requirements. Stage 2A of
this proposed ruie does not require
systems to conduct any additional
monitoring. They will continue to
monitor at Stage 1 DBPR locations.
Because the LRAA calculation is the
same as the RAA calculation if there is
only one site, Stage 2A compliance only
applies to systems that monitor at more
than one site and will only affect
medium and large surface water systems
(serving at least 10,000 people) or
systems with multiple plants. Thus, the
majority of ground water systems, small
surface water systems, and some
consecutive systems are not affected by
the proposed Stage 2A requirements.
e. TTHM and HAAS as Indicators. In
part, both the TTHM and HAAS classes
are regulated because they occur at high
levels and represent chlorination
byproducts that are produced from
source waters with a wide range of
water quality. The combination of
TTHM and HAAS represent a wide
variety of compounds resulting from
bromine substitution and chlorine
substitution reactions (i.e., bromoform
has 3 bromines, TCAA has 3 chlorines,
BDCM has one bromine and two
chlorines, etc). EPA believes that the
TTHM and HAAS classes serve as an
indicator for unidentified and
unregulated DBFs. EPA believes that
controlling the occurrence levels of
TTHM and HAAS will control the levels
of all chlorination DBFs to some extent.
3. Request for Comment
EPA requests comment on the
alternative MCL strategies that were
considered by the Advisory Committee
and the determination to propose the
Preferred Alternative in combination
with the IDSE as the preferred
regulatory strategy. EPA also requests
comment on whether the proposed
approach will reduce peak DBF levels.
EPA requests comment on the phased
MCL strategy and whether or not it will
facilitate compliance with the LRAA.
EPA also requests comment on the Stage
2A MCLs of 0.120 mg/L TTHM and
0.100 mg/L HAAS as LRAAs and on the
long-term MCLs of 0.080 mg/L TTHM
and 0.060 mg/L HAA5 as LRAAs.
E. Requirements for Peak TTHM and
HAAS Levels
1. What Is EPA Proposing Today?
Today, EPA is proposing that,
concurrent with Stage 2B, systems must
specifically document occurrences of
peak DBP levels, termed significant
excursions. In support of this provision,
EPA is proposing that States, as a
special primacy condition, develop
criteria for determining whether a
system has a significant excursion. EPA
has developed draft guidance for
systems and States on how systems may
determine whether they have significant
excursions. EPA is also proposing that
a system that has a significant excursion
must: (1) Evaluate distribution system
operational practices to identify
opportunities to reduce DBP levels
(such as tank management to reduce
residence time and flushing programs to
reduce disinfectant demand), (2)
prepare a written report of the
evaluation, and (3) no later than the
next sanitary survey, review the
evaluation with their State. This review
will take place under the sanitary
survey components calling for the State
to review monitoring, reporting, and
data verification and system
management and operation.
2. How Was This Proposal Developed?
Because individual measurements
from a location are averaged over a four-
quarter period to determine compliance,
there may be occurrence levels that
exceed the MCL even when a system is
in compliance with an LRAA MCL. EPA
and the Advisory Committee were
concerned about these exposures to
peak levels of DBFs and the possible
risk they might pose. This concern was
clearly reflected in the Agreement in
Principle, which states,
"Recognizing that significant
excursions of DBP levels will sometimes
occur, even when systems are in full
compliance with the enforceable MCL,
public water systems that have
significant excursions during peak
periods are to refer to EPA guidance on
how to conduct peak excursion
evaluations, and how to reduce such
peaks. Such excursions will be reviewed
as part of the sanitary survey process.
EPA guidance on DBP level excursions
will be issued prior to promulgation of
the final rule and will be developed in
consultation with stakeholders."
In evaluating this recommendation,
EPA believes that the Advisory
Committee's intent was clear with
regard to the need for guidance on how
to evaluate and reduce significant
excursions. However, the Agreement is
less clear on how, and where, to define
what constitutes a significant excursion,
and how to define the scope of the
evaluation. EPA draft guidance
recommends several approaches for
determining whether significant
excursions have occurred. While today's
proposal requires an evaluation only of
distribution system operational
practices, EPA believes that many
systems would benefit from a broader
evaluation that includes treatment plant
and other system operations.
EPA recognizes that different
stakeholders have different points of
view on whether specific criteria that
initiate the evaluation of significant
excursions should be included in the
rule or in guidance. EPA also recognizes
that different stakeholders may have
different perspectives on how to
identify a significant excursion. For this
proposal, EPA has prepared draft
guidance for systems and States on how
to (1) determine whether a significant
excursion has occurred, using several
different options, (2) conduct significant
excursion evaluations, and (3) reduce
significant excursion occurrence.
3. Request for Comment
EPA requests comment on the
proposed approach for addressing
significant excursions and on the draft
guidance. Is a special primacy condition
the appropriate means for allowing
flexibility in identifying significant
excursions while ensuring that such
evaluations occur? Is the sanitary survey
the appropriate mechanism for
reviewing significant excursion data
with the State? Should a system be
required to take corrective action when
significant excursions occur? Should the
required scope of the evaluation be
expanded beyond distribution system
operations?
EPA also requests comment on
whether specific criteria that initiate the
evaluation of significant excursions
should be included in the rule or -in
guidance. EPA requests comment on
how to identify significant excursions
(regardless of whether the criteria are in
the rule or in guidance). For example,
should the significant excursion be
based on an individual measurement,
e.g., any measurement being 25 or 50%
over either the TTHM or HAAS MCLs?
Alternatively, should the determination
of a significant excursion be based on a
certain level of variability among
multiple measurements? For example,
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should the significant excursion be
based on the standard deviation of the
LRAA exceeding specific numerical
values for either TTHM (e.g., 0.020 rag/
1) or HAAS (e.g., 0.015 mg/L)? Or should
the excursion be based on a relative
measure of variability (e.g., a relative
standard deviation exceeding 25% or
50%) with the condition of a threshold
average concentration also being
exceeded (e.g., an LRAA needing to be
at least 0.040 mg/1 for TTHM or 0.030
mg/1 for HAA5)? EPA requests comment
on the above approaches or alternative
approaches for determining whether a
significant excursion has occurred. EPA
also requests comment on whether
different approaches maybe appropriate
for large and small systems.
F. BAT for TTHM and HAAS
1. What Is EPA Proposing Today?
Today, EPA is proposing that the best
available technology (BAT) for the
TTHM and HAAS LRAA MCLs (0.080
mg/L and 0.060 mg/L respectively) be
one of the three following technologies:
(1) GAG adsorbers with at least 10
minutes of empty bed contact time and
an annual average reactivation/
replacement frequency no greater than
120 days, plus enhanced coagulation or
enhanced softening.
(2) GAG adsorbers with at least 20
minutes of empty bed contact time and
an annual average reactivation/
replacement frequency no greater than
240 days.
(3) Nanofiltration (NF) using a
membrane with a molecular weight cut
off of 1000 Daltons or less (or
demonstrated to reject at least 80% of
the influent TOG concentration under
typical operating conditions).
EPA is proposing a different BAT for
consecutive systems than for wholesale
systems to meet the TTHM and HAAS
LRAA MCLs. The proposed consecutive
system BAT is chloramination with
management of hydraulic flow and
storage to minimize residence time in
the distribution system.
2. How Was This Proposal Developed?
a. Basis for the BAT. The Safe
Drinking Water Act directs EPA to
specify BAT for use in achieving
compliance with the MCL. Systems
unable to meet the MCL after
application of BAT can get a variance
(see section V.L. for a discussion of
variances). Systems are not required to
use BAT in order to comply with the
MCL. They can use other technologies
as long as they meet all drinking water
standards and are approved by the State.
EPA examined BAT using two
different methods: (1) EPA analyzed
data from the Information Collection
Rule treatment studies and (2) EPA used
the Surface Water Analytical Tool
(SWAT), a model developed to compare
alternative regulatory strategies. Both
analyses support the BAT options
proposed today. The results of each
analyses are presented in the following
two sections.
i. BAT analysis using the Information
Collection Rule treatment studies. EPA
analyzed data from the Information
Collection Rule treatment studies
(Information Collection Rule Treatment
Study Database CD-ROM, Version 1.0,
USEPA 2000m; Hooper and Allgeier
2002). The treatment studies were
designed to evaluate the technical
feasibility of using GAG and NF to
remove DBP precursors prior to the
addition of chlorine-based disinfectants.
Systems were required to conduct an
Information Collection Rule treatment
study based on TOG levels in the source
or finished water. Specifically, surface
water plants with annual average source
water TOG concentrations greater than 4
mg/L and ground water plants with
annual average finished water TOG
concentrations greater than 2 mg/L were
required to conduct treatment studies.
Thus, the plants required to conduct
treatment studies generally had waters
with organic DBP precursor levels that
were significantly higher than the
Information Collection Rule national
plant medians of 2.7 mg/L for source
water at surface water plants and 0.2
mg/L for finished water at ground water
plants (USEPA 2003o).
Plants that conducted GAG studies
typically evaluated performance at two
empty bed contact times, 10 and 20
minutes, over a wide range of
operational run times to evaluate the
variable nature of TOG removal by GAG.
This allowed GAG performance to be
assessed with respect to empty bed
contact time as well as reactivation/
replacement frequency. Plants that
conducted membrane treatment studies
evaluated one or two nanofiltration
membranes with molecular weight
cutoffs less than 1000 Daltons.
Regardless of the technology evaluated,
all treatment studies evaluated DBP
formation in the effluent from the
advanced process under simulated
distribution system conditions
representative of the average residence
time and using free chlorine as the
primary and residual disinfectant, (For
more information on the Information
Collection Rule treatment study
requirements and testing protocols, see
USEPA 1996 a and b.)
Based on the treatment study results,
GAG is effective for controlling DBP
formation for waters with influent TOG
concentrations below approximately 6
mg/L (based on the Information
Collection Rule and NRWA data, over
90 percent of plants have average
influent TOG levels below 6 mg/L
(USEPA 2003o)). Of the plants that
conducted an Information Collection
Rule GAG treatment study,
approximately 70% of the surface water
plants studies could meet the 0.080 mg/
L TTHM and 0.060 mg/L HAAS MCLs,
with a 20% safety factor (i.e., 0.064 mg/
L and 0.048 mg/L, respectively) using
GAG with 10 minutes of empty bed
contact time and a 120 day reactivation
frequency, and 78% of the plants could
meet the MCLs with a 20% safety factor
using GAG with 20 minutes of empty
bed contact time and a 240 day
reactivation frequency. As discussed
previously, the treatment studies were
conducted at plants with poorer water
quality than the national average.
Therefore, EPA believes that much
higher percentages of plants nationwide
could meet the MCLs with the proposed
GAG BATs.
Among plants using GAG, larger
systems would likely realize an
economic benefit from on-site
reactivation, which could allow them to
use smaller, ID-minute empty bed
contact time contactors with more
frequent reactivation (i.e., 120 days or
less). Most small systems would not
find it economically advantageous to
install on-site carbon reactivation
facilities, and thus would opt for larger,
20-minute empty bed contact time
contactors, with less frequent carbon
replacement (i.e., 240 days or less).
The proposed reactivation/
replacement interval for the 20 minute
contactor (i.e., 240 days) is double the
reactivation/replacement interval for 10
minute contactor (i.e., 120 days). This is
based on the assumption of a linear
relationship between empty bed contact
time and the reactivation interval (e.g.,
a doubling of the empty bed contact
time will result in a doubling of the
reactivation interval). The data from the
Information Collection Rule treatment
studies indicates that this linear
relationship may not always hold and
that doubling the empty bed contact
time generally results in more than a
doubling of the reactivation interval.
While there may be some operational
advantage in using larger empty bed
contact times, the larger contactors will
result in additional capital
expenditures. Furthermore, the
economic optimization of a GAG
process must also consider the number
of smaller contactors in parallel, since it
may be advantageous to operate a larger
number of smaller contactors in parallel,
allowing each individual contactor to be
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49589
operated for a longer period of time.
Based on these considerations, and the
analysis of subject matter experts, it was
concluded that the proposed
combination of GAG empty bed contact
times and reactivation/replacement
intervals were reasonable for BAT.
The Information Collection Rule
treatment study results also
demonstrated that nanofiltration was
the better DBF control technology for
ground water sources with high TOC
concentrations (i.e., above
approximately 6 mg/L). The results of
the membrane treatment studies showed
that all ground water plants could meet
the 0.080 mg/L TTHM and 0.060 mg/L
HAA5 MCLs, with a 20% safety factor
(i.e., 0.064 mg/L and 0.048 mg/L,
respectively) at the average distribution
system residence time using
nanofiltration. Nanofiltration would be
less expensive than GAG for high TOC
ground waters, which generally require
minimal pretreatment prior to the
membrane process. Also, nanofiltration
is an accepted technology for treatment
of high TOC ground waters in Florida
and parts of the Southwest, areas of the
country with elevated TOC levels in
ground waters.
ii. BAT analysis using the SWAT. The
second method that EPA used to
examine alternatives for BAT was the
SWAT model that was developed to
compare alternative regulatory
strategies. EPA modeled the following
BAT options: enhanced coagulation/
softening with chlorine (the Stage 1
DBPR BAT); enhanced coagulation/
softening with chlorine and no
predisinfaction; enhanced coagulation
and GAC10; enhanced coagulation and
GAC20; and enhanced coagulation and
chloramines. Enhanced coagulation/
softening is required under the Stage 1
DBPR at subpart H conventional
filtration plants. In the model, GAC10
was defined as granular activated
carbon with an empty bed contact time
of 10 minutes and a reactivation or
replacement interval of 90 days or
longer. GAC20 was defined as granular
activated carbon with an empty bed
contact time of 20 minutes and a
reactivation or replacement interval of
90 days or longer. EPA assumed that
systems would be operating to achieve
both the Stage 2B MCLs of 0.080 mg/L
TTHM and 0.060 mg/L HAA5 as an
LRA.A and the SWTR removal and
inactivation requirements of 3-log for
Giardia and 4-log for viruses. EPA also
evaluated the BAT options under the
assumption that plants operate to
achieve DBF levels 20% below the MCL
(safety factor). These assumptions along
with other inputs for the SWAT runs are
consistent with those used in the
Economic Analysis of today's proposed
rule (USEPA 2003i).
The compliance percentages
forecasted by the SWAT model are
indicated in Table V—1. EPA estimates
that more than 97% of large systems
will be able to achieve the Stage 2B
MCLs regardless of post-disinfection
choice if they were to apply one of the
proposed GAG BATs, i.e., enhanced
coagulation (EC) and GAC10 (Seidel
Memo, 2001). As shown in the Stage 2
DBPR Occurrence document (USEPA
2003o), the source water quality (e.g.,
DBP precursor levels) in medium and
small systems is expected to be
comparable to or better than that for the
large systems. Based on the large system
estimate, EPA believes it is conservative
to assume that at least 90% of medium
and small systems will be able to
achieve the Stage 2B MCLs if they were
to apply one of the proposed GAG
BATs. EPA assumes that small systems
may adopt GAC20 in a replacement
mode (with replacement every 240 days)
over GAC10 because it may not be
economically feasible for some small
systems to install and operate an on-site
GAG reactivation facility. Moreover,
some small systems may find
nanofiltration cheaper than the GAC20
in a replacement mode if their specific
geographic locations cause a relatively
high cost for routine GAG shipment.
TABLE v-1.—SWAT MODEL PREDICTIONS OF PERCENT OF LARGE PLANTS IN COMPLIANCE WITH TTHM AND HAA5
STAGE 2B MCLs AFTER APPLICATION OF SPECIFIED TREATMENT TECHNOLOGIES
Technology *
EC & GAC10
EC & GAC20
EC & All Chloramines :
Compliance with 0.080 mg/L (TTHM)/0.060 mg/L
(HAAS) LRAAs
Residual disinfectant
Chlorine
73.5
73.4
100
100
NA
Chloramine
76.9
88.0
97.1
100
83.9
All systems
74.8
78.4
99.1
100
NA
Compliance with 0.064 mg/L (TTHM)/0.048 mg/L
(HAAS) LRAAs (MCLs with 20% safety factor)
Residual disinfectant
Chlorine
57.2
44.1
100
100
NA
Chloramine
65.4
62.7
95.7
100
73.6
All systems
60.4
50.5
98.6
100
NA
' Enhanced coagulation/softening is required under the Stage 1 DBPR for conventional plants.
b. Basis for the Consecutive System
BAT. EPA believes that the best
compliance strategy for consecutive
systems is to collaborate with
wholesalers on the water quality they
need. For consecutive systems that are
having difficulty meeting the MCLs,
EPA is proposing a BAT of
chloramination with management of
hydraulic flow and storage to minimize
residence time in the distribution
system. EPA is proposing a different
BAT than for wholesale systems because
a consecutive system's source water has
already been disinfected and contains
DBPs that cannot be effectively removed
or controlled with the BATs proposed
for wholesale systems. EPA believes the
proposed consecutive system BAT is an
effective means for consecutive systems
to meet the MCLs.
Chloramination has been used for
residual disinfection for many years to
minimize the formation of chlorination
DBPs, including TTHM and HAA5
(Stage 2 Technology and Cost
Document, USEPA 2003k). The BAT
provision to manage hydraulic flow and
minimize residence time in the
distribution system is to facilitate the
maintenance of the chloramine residual
and minimize the likelihood for
nitrification. Nitrification, the process
by which microbes convert free
ammonia to nitrate and nitrite, is a
concern for systems using chloramines.
Nitrification, however, can be controlled
with appropriate chlorine to ammonia
ratios, increasing flow in low demand
areas, and increasing storage tank
turnover. EPA proposes that systems
implementing the consecutive system
BAT must do the following: (1)
Maintain a chloramine residual
throughout the distribution system, (2)
develop and submit a plan that
indicates actions that will be taken to
minimize the residence time of water
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within the distribution system, (3) have
the plan approved by the Primacy
Agency, and (4) implement the plan as
approved by the Primacy Agency.
Minimum components of the
management plan would include
periodic scheduled flushing of all dead
end pipes and storage vessels through
which water is delivered to customers,
and hydraulic flow control procedures
that routinely circulate water in all
storage vessels within the distribution
system.
EPA believes that the BATs proposed
for wholesale systems are not
appropriate for consecutive systems
because each of these BATs, when
applied to water with DBFs, raises other
concerns. GAG is not cost-effective for
removing DBPs. In addition, dioxin, a
carcinogen, may be formed during GAG
regeneration if GAG has been used to
adsorb chlorinated DBPs. Nanofiltration
is only moderately effective at removing
THMs or HAAs if membranes that have
a very low molecular weight cutoff and
very high cost of operation are
employed. Therefore, GAG and
nanofiltration are not appropriate BATs
for consecutive systems.
3. Request for Comment
EPA requests comment on the
proposed BATs including the BAT for
consecutive systems.
G. MCL, BAT, and Monitoring for
Bromate
1. What Is EPA Proposing Today?
EPA is proposing today that the MCL
for bromate for systems using ozone
remain at 0.010 mg/L as an RAA for
samples taken at the entrance to the
distribution system as established by the
Stage 1 DBPR and as provided for under
the risk-balancing provisions of section
1412(b)[5) of the SDWA. EPA's proposal
is consistent with the recommendation
of the Stage 2 M-DBP Advisory
Committee, which considered the
potential that reducing the bromate
MCL could both increase the
concentration of other DBPs in the
drinking water and interfere with the
efficacy of microbial pathogen
inactivation. In addition, as required by
the SDWA and as recommended by the
Advisory Committee, EPA will review
the bromate MCL as part of the 6-year
review process and determine whether
the MCL should remain at 0.010 mg/L
or be reduced to a lower level. As a part
of that review, EPA will consider the
increased utilization of alternative
technologies, such as UV, and whether
the risk/risk concerns reflected in
today's proposal remain valid.
Because EPA is not revising the Stage
1 DBPR bromate MCL, EPA is not
proposing a revised BAT for bromate.
The Stage 1 DBPR BAT for bromate is
defined as control of ozone treatment
processes to reduce production of
bromate. EPA also determined that it
was not necessary to regulate bromate in
non-ozone systems that use
hypochlorite.
Finally, EPA is proposing to modify
the criterion for a system that uses
ozone (and therefore must monitor for
bromate) to qualify for reduced bromate
monitoring from one sample per ozone
plant per month to one sample per plant
per quarter.
2. How Was This Proposal Developed?
a, Bromate MCL. Bromate is a
principal byproduct from ozonation of
bromide-containing source waters. As
described in more detail later, making
the bromate MCL more stringent has the
potential to decrease current levels of
microbial protection, impair the ability
of systems to control resistant pathogens
like Cryptospondium, and increase
levels of DBPs from other disinfectants
that may be used instead of ozone.
EPA estimates that the 1 in 10,000
excess lifetime cancer risk level for
bromate is 0.005 mg/L. EPA proposed
and ultimately finalized an MCL of
0.010 mg/L in the Stage 1 DBPR,
primarily because available analytical
detection methods for bromate could
only reliably measure to 0.01 mg/L
(USEPA 1994b). Analytical methods for
bromate are now available to quantify
bromate concentrations as low as 0.001
mg/L. Due to the availability of lower
detection methods for bromate, as part
of the Stage 2 M-DBP Advisory
Committee deliberations, EPA
considered revising the MCL to 0.005
mg/L or lower.
As a disinfectant, ozone is highly
effective against a broad range of
microbial pathogens including bacteria,
viruses, and protozoa. Moreover, ozone
is one of the few disinfectants available
in water treatment that is capable of
inactivating Cryptosporidium, a
protozoan which can cause severe
intestinal disorders and can be deadly to
those with compromised immune
systems. The oxidizing properties of
ozone are also valuable for treatment
objectives like control of tastes and
odors and removal of iron and
manganese. In contrast, chlorine, the
most common disinfectant and oxidant
in water treatment, is substantially less
effective for controlling
Cryptosporidium. Chlorine dioxide,
while capable of providing low levels of
inactivation for Cryptosporidium,
typically cannot be used at high doses
without violating the MCL for chlorite,
a byproduct of chlorine dioxide. UV
light is highly effective against
Cryptosporidium and Giardia and most
viruses, but has not been used
extensively to treat drinking water in
the United States.
As of early 2000, there were 332
plants of various sizes using ozone
(Overbeck 2000) and 58 plants that were
planning to install ozonation (Rice
2000—personal communication: email
7/14/2000). A significant percent of
current ozone plants use ozone for some
portion of their disinfection objective
(Rice, 2000—personal communication:
email 7/14/2000). An ozone system that
could not meet a 0.005 mg/L bromate
MCL would have three primary options:
decrease the ozone dose; switch to a
different disinfectant; or install an
advanced filtration process such as
membranes, sometimes in combination
with the first two options. Of these three
options, the third is likely effective but
very expensive, while the first two
create the risk either of reducing
microbial protection for a wide range of
microbial pathogens, or of increasing
formation of DBPs other than bromate.
In an attempt to achieve a lower level
of bromate, some systems might be
driven to reduce the applied ozone dose
to the minimum necessary for regulatory
compliance or switch to other treatment
processes. Many systems currently
achieve more disinfection than is
required by the SWTR and if a system
were to simply lower the ozone dose,
protection from pathogens may be
compromised. In addition, since
inactivation of Cryptosporidium
requires much higher ozone doses than
Giardia inactivation, systems cannot
achieve Cryptosporidium inactivation
with low ozone doses.
If a system were to lower the ozone
dose and supplement with an additional
disinfectant, or switch entirely to a
different disinfectant, the system may
not achieve the same level of microbial
protection as is afforded by ozonation.
Also, other potentially harmful
byproducts from the different
disinfectant would be produced.
During the Stage 2 M-DBP Advisory
Committee discussions, the TWG
evaluated the impact of reducing the
bromate MCL from 0.010 mg/L to 0.005
mg/L as an annual average. The TWG
concluded that many systems currently
using ozone or predicted to install
ozone to inactivate microbial pathogens
would have significant difficulty
maintaining bromate levels at or below
0.005 mg/L. In the Information
Collection Rule survey of systems
serving greater than 100,000 people, all
of the ozone plants had annual average
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49591
bromate concentrations below the 0.010
mg/L level (USEPA 2003o). However,
approximately 20% of these ozone
plants did not meet the 0.005 mg/L
level. Using the assumption that
systems operate their plants using a
safety margin of 20% below the MCL,
about 30% of ozone plants did not
reliably attain this level (0.004 mg/L).
During the Information Collection Rule,
for the first half of 1998, much of the
U.S. was wetter than normal (NOAA
1998). This hydrogeological condition
often leads to lower than normal
bromide concentrations due to dilution
by higher water flows. In the second
half of 1998, California continued to
experience El Nino rains (40% of
Information Collection Rule ozone
plants were located in California) but
many other areas of the country such as
Texas and Florida experienced a
drought. The percentage of ozone
systems unable to achieve 0.005 mg/L
bromate would likely increase during
years in which bromide concentrations
in California were elevated as
consequence of drought.
The ability of systems to use ozone to
meet Cryptosporidium treatment
requirements proposed under the
LT2ESWTR would be diminished if the
bromate MCL was decreased from 0.010
to 0.005 mg/L. The proposed
LT2ESWTR will require a subset of
systems, based on source water
pathogen levels, to provide from 1.0 to
2.5 logs of additional treatment for
Cryptosporidium, Ozone doses required
to inactivate Cryptosporidium are
substantially greater than those required
for Giardia and viruses. To assess the
potential impact of a lower bromate
MCL on the ability of systems to treat
for Cryptosporidium, the TWG
estimated the percentage of treatment
plants that could use ozone to inactivate
from 0.5 to 2.5 log of Cryptosporidium
without exceeding a bromate MCL of
either 0.005 or 0.010 mg/L (USEPA
2003i). These estimations were based on
analyses of Information Collection Rule
source water quality data, coupled with
projected ozone dose requirements for
Cryptosporidium. This analysis suggests
that 88% of systems could use ozone to
achieve 1 log of Cryptosporidium
inactivation and 47% could inactivate 2
log while complying with a bromate
MCL of 0.010 mg/L. With the bromate
MCL reduced to 0.005 mg/L, though,
these estimates drop to 67% of systems
able to inactivate 1 log of
Cryptosporidium with ozone and only
14% able to inactivate 2 log. The
number of plants predicted to be able to
treat for Cryptosporidium with ozone
and meet a 0.005 mg/L standard was
further reduced when periods of higher
bromide levels, similar to drought
conditions, were modeled. This trend is
further exacerbated since the proposed
LT2ESWTR would require more
stringent ozone operating conditions
(such as higher ozone doses and longer
contact times) than under current
surface water treatment requirements for
the subset of plants with higher
Cryptosporidium concentrations in their
source water and would thus result in
higher bromate formation than assumed
by the TWG. Thus, as systems are
required to meet more stringent
inactivation requirements, a large
number of systems would be forced to
select treatment processes other than
ozone if the bromate standard were
lowered to 0.005 mg/L.
The Stage 2 M-DBP Advisory
Committee considered that reducing the
bromate MCL to 0.005 mg/L could both
increase the concentration of other DBFs
in the drinking water and interfere with
the efficacy of microbial pathogen
inactivation. Therefore, the Advisory
Committee recommended, for purposes
of the Stage 2 DBPR, that the bromate
MCL remain at 0.010 mg/L. EPA will
review the bromate MCL as part of the
ongoing 6-year review process and
determine whether the MCL should
remain at 0.010 mg/L or be reduced to
a lower concentration based on new
information.
Today, EPA is proposing to leave the
bromate MCL at 0.010 mg/L, consistent
with the Advisory Committee's
recommendation. EPA believes that this
is a prudent step at this time, in order
to preserve microbial protection. EPA
will continue to analyze any new
bromate health effects data as they
become available. It is possible that EPA
may determine that the bromate MCL
should be decreased to 0.005 mg/L or
lower in a future rulemaking.
b. Bromate in hypochlorite solutions.
The Stage 2 M-DBP Advisory
Committee also discussed the issue of
hypochlorite solutions contaminated
with bromate. This contamination can
occur during the production of
hypochlorite solutions from natural salt
deposits. The range of bromate
concentrations in hypochlorite stock
solutions varies widely (Bolyard et a].
1992; Chlorine Institute 1999, 2000).
Moreover, the bromate contained in the
stock solution is diluted upon addition
to the drinking water. From data on
Information Collection Rule ozone
systems that used hypochlorite versus
those that used gaseous chlorine, the
TWG estimated that hypochlorite
solutions contributed an average of
0.001 mg/L bromate.
The Advisory Committee discussed
these results and, since the bromate
level resulting from hypochlorite
solutions was small compared to the
MCL, did not recommend regulating
bromate at systems not using ozone
(non-ozone systems). The Advisory
Committee recognized that ozone
systems also using hypochlorite will
have to be careful about the quality of
their stock solution.
c. Criterion for reduced bromate
monitoring. Because more sensitive
bromate methods are now available,
EPA is proposing a new criterion for
reduced bromate monitoring. In the
Stage 1 DBPR, EPA required ozone
systems to demonstrate that source
water bromide levels, as a running
annual average, did not exceed 0.05 mg/
L. EPA elected to use bromide as a
surrogate for bromate in determining
eligibility for reduced monitoring
because the available analytical method
for bromate was not sensitive enough to
quantify levels well below the bromate
MCL of 0.010 mg/L.
In section V.O., EPA is proposing
several new analytical methods for
bromate that are far more sensitive than
the existing method. Since these
methods can measure bromate to levels
of 0.001 mg/L or lower, EPA is
proposing to replace the criterion for
reduced bromate monitoring (source
water bromide running annual average
not to exceed 0.05 mg/L) with a bromate
running annual average not to exceed
0.0025 mg/L.
In the past, EPA has often set the
criterion for reduced monitoring
eligibility at 50% of the MCL, which
would be 0.005 mg/L. However, as
discussed before, EPA is proposing that
the MCL for bromate remain at 0.010
mg/L, a level that is higher than EPA's
usual excess cancer risk range of 10(-4)
to 10(-6) at 2xlO(-4) because of risk
tradeoff considerations. EPA believes
that the decision for reduced monitoring
is separate from these risk tradeoff
considerations. Risk tradeoff
considerations influence the selection of
the MCL, while reduced monitoring
requirements are designed to ensure that
the MCL, once established, is reliably
and consistently achieved. Requiring a
running annual average of 0.0025 mg/L
for the reduced monitoring criterion
allows greater confidence that the
system is achieving the MCL and thus
ensuring public health protection.
3. Request for Comment
EPA requests comment on the
decision to maintain the Stage 1 DBPR
bromate BAT and MCL of 0.010 mg/L.
EPA also requests comment on the
decision not to require bromate
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monitoring at non-ozone systems that
use hypochlorite.
EPA requests comment on whether
the criterion for reduced bromate
monitoring should be set at a level other
than 0.0025 mg/L, and a rationale for
setting it at that level.
H. Initial Distribution System
Evaluation (IDSE)
The IDSE is an important part of
today's proposed regulation that is
intended to identify sample locations
for Stage 2B compliance monitoring that
represent distribution system sites with
high DBF concentrations.
I. What is EPA Proposing Today?
EPA is proposing a requirement for
systems to perform an Initial
Distribution System Evaluation (IDSE).
Systems will collect data on DBP levels
throughout their distribution system,
evaluate these data to determine which
sampling locations are most
representative of high DBP levels and
compile this information into a report
for submission to the primacy agency,
a. Applicability. All community water
systems, and large nontransient
noncommunity water systems (those
serving at least 10,000 people) that add
a primary or residual disinfectant other
than ultraviolet light, or that deliver
water that has been treated with a
primary or residual disinfectant other
than ultraviolet light (i.e., consecutive
systems) are required to conduct an
IDSE under the proposed rule. The IDSE
requirement for systems serving fewer
than 500 people may be waived if the
State determines that the monitoring
site approved for Stage 1 DBPR
compliance is sufficient to represent
both high HAA5 and high TTHM
concentrations. The State must submit
criteria for this waiver determination to
EPA as part of their primacy
application. States may decide to waive
the IDSE requirement for all systems
serving fewer than 500 or some subset
of all systems serving fewer than 500 if
the State determines that it is
appropriate. EPA is developing an IDSE
Guidance Manual that will include
guidance to States on situations for
which a waiver would be appropriate
(USEPA 2003J).
b. Data collection. IDSEs are intended
to help identify and select Stage 2B
compliance monitoring sites that
represent high concentrations of TTHMs
and HAAS. To be able to identify these
sites, systems and States must have
monitoring data collected from
throughout their distribution systems.
Therefore, under today's proposed rule,
systems are required to collect
monitoring data on the concentrations
of these DBFs. There are three possible
approaches by which a system can meet
the IDSE requirement.
i. Standard monitoring program. The
standard monitoring program requires
one year of monitoring on a specified
schedule throughout the distribution
system. The frequency and number of
samples required under the standard
monitoring program is determined by
source water type, number of treatment
plants, and system size (see section VJ.
for a more detailed discussion of the
specific monitoring requirements). Prior
to commencing the standard monitoring
program, systems must prepare a
monitoring plan. EPA's IDSE Guidance
Manual will provide guidance on
selecting monitoring sites and
conducting the standard monitoring
program (USEPA 2003J). As
recommended by the Advisory
Committee, EPA is proposing that the
standard monitoring program results are
not to be used for determining
compliance with MCLs and that systems
will not be required to report IDSE
results in the Consumer Confidence
Report.
ii. System specific study. Under this
approach, systems may choose to
perform a system-specific study based
on earlier monitoring studies or other
data analysis in lieu of the standard
monitoring program. These studies must
provide equivalent or better information
than the standard monitoring program
for selecting sites that represent high
TTHM and HAA5 levels. Examples of
alternative studies are: (1) Recent TTHM
and HAAS monitoring data that
encompass a wide range of sample sites
representative of the distribution
system, including those judged to
represent high TTHM and HAAS
concentrations and (2) hydraulic
modeling studies that simulate water
movement in the distribution system.
Historical TTHM and HAAS results
submitted by systems must have been
generated by certified laboratories and
must include the system's most recent
data. Treatment plant and distribution
system characteristics at the time of
historical data collection must reflect
the current plant operations and
distribution system. EPA's IDSE
Guidance Manual will include a
guidance for system-specific studies and
how to determine whether site-specific
data could be sufficient to meet the
IDSE requirements (USEPA 2003J).
iii. 40/30 certification. Under this
approach, systems certify to their
primacy agency that all required Stage
1 DBPR compliance samples were
properly collected and analyzed during
the two years prior to the start of the
IDSE, and all individual compliance
samples were < 0.040 mg/L for TTHM
and <0.030 mg/L for HAA5. Properly
collected and analyzed compliance
samples are those taken at required
locations at times specified in the
system's Stage 1 DBPR monitoring plan
and analyzed by certified laboratories.
Systems not required to collect Stage 1
DBPR compliance samples can not
utilize the 40/30 certification approach
because they do not have data to
determine sampling locations that
represent high concentrations of TTHMs
and HAAS. Systems that qualify for
reduced monitoring for the Stage 1
DBPR during the two years prior to the
start of the IDSE, may use results of both
routine and reduced Stage 1 DBPR
monitoring to prepare the 40/30
certification. Large ground water
systems may not have two years of
HAA5 data to evaluate due to the timing
of the Stage 1 DBPR and the IDSE
requirements. EPA is proposing that, if
two years worth of HAAS data are not
available, large ground water systems
evaluate the most recent two years of
TTHM data including data collected in
accordance with the 1979 TTHM rule
and all available HAA5 compliance data
collected up to nine months following
promulgation of this rule when making
the 40/30 certification. Similarly, small
wholesale and consecutive systems
required to submit their IDSE report no
later than two years after publication of
the final rule will evaluate al! available
Stage 1 DBPR compliance data collected
up to nine months following
promulgation.
c. Implementation. All systems
subject to the IDSE requirement under
the proposed rule (except those
receiving a very small system waiver
from the State) must submit a report to
the primacy agency. The requirements
for the report depend upon the IDSE
data collection alternative that the
system selects and are listed in Table V-
2.
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49593
TABLE V-2.—IDSE REPORT REQUIREMENTS
IDSE data collection
alternative
IDSE report requirements
Standard Monitoring Pro-
gram.
System Specific Study
W/30 Certification
All standard monitoring program TTHM and HAA5 analytical results, the original monitoring plan, and an expla-
nation of any deviations from that plan.
A schematic of the distribution system.
Recommendations and justification for where and during what month(s) Stage 2B monitoring should be con-
ducted.
All studies, reports, analytical results and modeling.
A schematic of the distribution system.
Recommendations and justification for where and during what month(s) Stage 2B monitoring should be con-
ducted
A certification that all required compliance samples were properly collected and analyzed during the two years
prior to the start of the IDSE and all individual compliance samples were < 0.040 mg/L for TTHM and <0.030
mg/L for HAAS.
Results of compliance samples taken after the IDSE was scheduled to begin and before the IDSE report was
submitted.
Recommendations for where and during what month(s) Stage 2B monitoring should be conducted.
All IDSE reports must include
ecommendations for the location and
schedule for the Stage 2B monitoring.
rhe number of sampling locations and
he criteria for their selection are
described in §141.605 of today's
proposed rule, and in section V.I.
jenerally, a system must recommend
ocations with the highest LRAAs unless
t provides a rationale (such as ensuring
'eographical coverage of the
distribution system instead of clustering
ill sites in a particular section of the
distribution system) for selecting other
ocations. Systems must consider both
:heir compliance data and IDSE data in
naking this determination. In addition
o specifying a protocol for identifying
•ecommended monitoring sites in the
Tile language, EPA will provide
.uidance for recommending compliance
nonitoring sites (including rationales
or systems to recommend sites that do
lot have the highest LRAA
:oncentrations) and preparing the IDSE
report. EPA will also provide a process
o address IDSE implementation issues
iuring the period prior to State primacy.
\t the time that systems serving fewer
han 10,000 people conduct their
nonitoring or analyze their site-specific
iata, many States may have primacy.
The compliance schedules for the
USE and other requirements of the
proposed rule are described in detail in
ection V.J. Systems serving at least
10,000 people (and those smaller
wholesale and consecutive systems
issociated with larger systems) will be
ollecting data for their IDSE prior to
State primacy. EPA intends to have an
DSE Guidance Manual available to
issist systems in performing the IDSE
USEPA 2003J). Primacy agencies will
specify requirements for systems that do
lot submit an IDSE report, or that have
lot, in the determination of the primacy
igency, conducted an adequate IDSE, in
addition to giving the system a
monitoring and reporting violation.
These requirements may include
repeating the IDSE while conducting
compliance monitoring at Stage 1
monitoring sites or conducting Stage 2
compliance monitoring at sites selected
by the State.
Consecutive systems are subject to the
IDSE requirements of today's proposed
rule. IDSE requirements for consecutive
systems are largely the same as for other
systems, but with two differences. First,
the schedule for completion of the IDSE
by a consecutive system is dependent
upon the population of the wholesale
system. If a consecutive system serving
fewer than 10,000 buys water from a
system that serves 10,000 or more
people, then this consecutive system
must comply within the same schedule
as that for systems > 10,000. Conversely,
if a wholesale system serves < 10,000
but sells water to a consecutive system
serving > 10,000, then both the
wholesale system and the consecutive
system must complete the IDSE within
the same schedule as that for systems >
10,000. The second difference for
consecutive systems is that the
procedure for recommending Stage 2B
compliance monitoring locations is
modified for consecutive systems
purchasing or receiving all of their
finished water from a wholesale system.
These modified procedures are
described in §141.605 of today's
proposed rule, and in section V.I.
2. How Was This Pr oposa! Developed?
The IDSE was recommended by the
Stage 2 M-DBP Advisory Committee.
The Advisory Committee believed that
maintaining Stage 1 DBPR sampling
sites for the Stage 2 DBPR would not
accomplish the objective of providing
consistent and equitable protection
across the distribution system.
a. Applicability. The M-DBP
Advisory Committee recommended that
an IDSE be performed on all community
systems to help to identify the locations
in the distribution system that represent
high DBF concentrations. EPA believes
that large nontransient noncommunity
water systems (those serving at least
10,000 people) also have distribution
systems that require further evaluation
to determine the most representative
locations of high DBF levels. Therefore,
large nontransient noncommunity
systems and all community systems are
required to perform an IDSE under
today's proposal.
States may waive the IDSE
requirement for those very small
systems (systems that serve fewer than
500 people) that monitor for Stage 1
DBPR compliance at the maximum
residence time site if the State
determines their maximum residence
time Stage 1 compliance monitoring site
is likely to capture both the high TTHM
and high HAAS levels within the
distribution system. The Advisory
Committee recommended this waiver be
included because many very small
systems have small distribution systems
and the high TTHM and high HAA5 site
is at the same location. The Advisory
Committee also recognized that not all
very small systems have a single
monitoring site that would represent
both high TTHM and high HAAS levels
(e.g., some rural systems with large
distribution systems) and thus did not
recommend a blanket IDSE waiver for
all very small systems.
b. Data collection. The data collection
requirements of the IDSE are designed
to find both high TTHM and high HAAS
sites (see section V.I. for IDSE
monitoring site locations). The IDSE is
intended as a one-time requirement.
High TTHM and HAA5 concentrations
often occur at different locations in the
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distribution system. The Stage 1 DBPR
monitoring sites identified as the
maximum location are selected
according to residence time. Because
HAAs can degrade in the distribution
system in the absence of sufficient
disinfectant residual (Baribeau et al.
2000), residence time alone is not an
ideal criterion for identifying high
HAAS sites. The Information Collection
Rule data show that of the four
monitoring locations sampled per
system, the one identified as the
maximum residence time location was
often not the location where the highest
DBF levels were found. In fact, over 60
percent of the highest HAAS LRAAs and
50 percent of the highest TTHM LRAAs
were found at sampling locations in the
system other than the maximum
residence time location (see section IV).
Thus the method and assumptions used
to select the Information Collection Rule
monitoring sites, and the Stage 1 DBPR
compliance monitoring sites, are not
sufficiently reliable to select Stage 2
DBPR compliance monitoring sites that
will capture high DBF levels.
This data analysis reveals that a
reevaluation of monitoring sites is
necessary at many systems to capture
sites with high DBP levels. The
Advisory Committee recommended
sample locations (based on distribution
disinfectant type) at widely distributed
sites (see section V.I. for details on IDSE
monitoring requirements). Monitoring at
additional sites across the distribution
system increases the chance of finding
sites with high DBP levels and targets
both DBFs that degrade, and DBFs that
form, as residence time increases in the
distribution system. EPA believes that
the required number of monitoring
locations plus Stage 1 monitoring
results provides an adequate
recharacterization of DBP levels
throughout the distribution system, at a
reasonable cost. With a
recharacterization of distribution
systems that focuses on both high
TTHM and HAAS occurrence, EPA
believes that high occurrence sites will
be better represented in this standard
monitoring program. Systems will be
required to take steps to address high
DBP levels at points that might
otherwise have gone undetected. EPA
believes that the decrease in DBP
exposure anticipated to result from the
transition from an RAA to an LRAA will
be augmented by the IDSE.
The frequency and number of samples
required for the standard monitoring
program decrease as system size
(population served) decreases and
depend on source water type. The
Advisory Committee believed that the
number of samples required for large
and medium surface water systems was
not necessary for small surface water
systems and ground water systems. The
majority of small systems have
distribution systems with simpler
designs than large systems. DBP
occurrence in ground water systems is
generally lower and less variable than in
surface water systems due to lower and
less variable precursor levels and much
less temperature variation (see section
IV).
Committee members recognized that
some systems have detailed knowledge
of their distribution systems by way of
hydraulic modeling and/or ongoing
widespread monitoring plans (well
beyond that required for compliance
monitoring) that would provide
equivalent or superior monitoring site
selection compared to IDSE monitoring.
Therefore, the Advisory Committee
recommended that such systems be
allowed to determine new monitoring
sites using system-specific data such as
historical monitoring data.
Systems that certify to their State that
all compliance samples taken in the two
years prior to the start of the IDSE were
< 0.040 mg/L TTHM and < 0.030 mg/L
HAA5 are not required to collect
additional DBP monitoring data because
the Advisory Committee determined
that these systems most likely would
not have high peak DBP levels. EPA
determined that this provision needed
to be more specific for three groups of
systems: (1) Those performing Stage 1
DBPR reduced monitoring, (2) large
ground water systems, and (3) small
systems required to conduct an early
IDSE. Today's proposal clarifies that
these systems may use a 40/30
certification. EPA recognizes that these
systems may have less compliance data
on which to base their 40/30
certifications. However, EPA believes
that the data that will be available are
sufficient to make a determination on
the most appropriate Stage 2B
monitoring locations.
c. Implementation. Systems are
required to submit an IDSE report so
that primacy agencies may review the
system's IDSE data collection efforts and
the Stage 2B monitoring locations
recommended by the system. Systems
serving at least 10,000 must submit their
IDSE report two years after rule
promulgation (which may be prior to
primacy for some States). The M-DBP
Advisory Committee recommended an
implementation schedule that would
allow systems sufficient time to make
site-specific risk determinations and
decisions regarding the simultaneous
implementation of the Stage 2 DBPR
and LT2ESWTR but not stretch out the
compliance time frame too far into the
future. This provision requires that
medium and large systems conduct and
complete site-specific risk
determinations (i.e., the IDSE and
LT2ESWTR Cryptosporidium
monitoring) as soon as possible after
rule promulgation. Since small systems
cannot begin their microbial monitoring
until after the results from the large
system microbial monitoring have been
analyzed, small systems have a longer
compliance time frame.
Systems that submit a 40/30
certification are required to submit that
certification as part of the IDSE report
and to include a recommended Stage 2B
monitoring plan. The monitoring plan is
required for these systems because the
Stage 2B MCL compliance monitoring
sites proposed today have
fundamentally different objectives than
the Stage 1 DBPR monitoring sites.
Additionally, many systems are
required to have more Stage 2
compliance monitoring sites than Stage
1 sites because high HAAS site may be
different than high TTHM sites.
3. Request for Comment
EPA requests comments on the IDSE
requirement and whether it is a good
tool to identify sites representative of
high TTHM and high HAA5 levels.
a. Applicability. EPA requests
comment on requiring large (serving
10,000 or more people) nontransient
noncommunity water systems to
perform an IDSE. Should NTNCWSs
serving fewer than 10,000 people be
required to conduct an IDSE? EPA also
requests comment upon whether States
should be able to waive IDSE
requirements for very small systems
(serving fewer than 500 people). Are
there objective criteria that the State
should use in waiving the requirement?
Should the State be allowed to grant
very small system waivers based on
some other criterion other than serving
a population <500? For example, should
the State be allowed to choose a higher
population cutoff? Should the State be
allowed to use a non-population
criterion such as simplicity of
distribution system to grant a very small
system waiver? If so, what should this
criterion be and how should
qualification be demonstrated?
b. Data collection. EPA requests
comment on the requirements for each
of the alternatives for data collection
under the proposed IDSE including: the
standard monitoring program, the
system-specific study, and the 40/30
certification. EPA requests comment on
whether systems with less than two
years of routine monitoring data should
be considered to have sufficient data to
utilize the 40/30 certification.
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49595
Specifically EPA requests comment on
whether systems on reduced
monitoring, large ground water systems,
and small systems required to conduct
an IDSE within the first two years after
promulgation should be prohibited from
submitting a 40/30 certification.
c. Implementation. EPA requests
comment on the requirement that large
and medium systems must collect data
and prepare their IDSE report prior to
State primacy. EPA requests comment
From the States regarding whether they
intend to be involved in the
consultations with systems collecting
data for IDSE or in the review of IDSE
reports that are submitted prior to State
arimacy. EPA is developing a plan to
.mplement the IDSE during the period
prior to State primacy. EPA requests
:omment on any issues that should be
addressed during this period to facilitate
:he IDSE.
r.. Monitoring Requirements and
Compliance Determination for Stage 2A
ind Stage 2B TTHM and HAAS MCls
1. What Is EPA Proposing Today?
Today's proposal includes new
-equirements for how systems must
nonitor TTHM and HAAS levels in
:heir distribution systems and how
systems must assess their monitoring
•esults to determine compliance with
ITHM and HAA5 MCLs. The new
nonitoring requirements are associated
,vith the IDSE (described in section V.H)
md Stage 2B of the proposed rule. The
lew compliance determination
•equirements relate to use of the
ocational running annual average
LRAA) for meeting proposed Stage 2A
md Stage 2B MCLs for TTHM and
iAAS (described in section V.D). This
section presents these proposed
nonitoring and compliance
letermination requirements for Stage
>A, the IDSE, and Stage 2B.
An important aspect of the proposed
PTHM and HAA5 monitoring
'equirements is the use of two different
ipproaches for determining the number
)f samples a system is required to
;ollect. One approach is plant-based.
Jnder the plant-based approach, a
iystem's TTHM and HAAS sampling
•equirements are determined by the
lumber of treatment plants in the
lystem and, in the case of consecutive
ystems, the number of consecutive
;ystem entry points. The second
ipproach is population-based. Under
he population-based approach, a
;ystem's sampling requirements are
nfiuenced by the number of people
erved, but not by the number of
reatment plants. EPA is proposing
topulation-based sampling
requirements only for IDSE and Stage
2B monitoring by consecutive systems
that purchase all of their finished water
year-round. However, EPA is requesting
comment on applying a population-
based approach to all systems for the
IDSE and Stage 2B compliance. The
discussion of monitoring requirements
in this section provides details on these
two approaches.
A number of factors affect DBP
formation, including the type and
amount of disinfectant used, water
temperature, pH, amount and type of
precursor material in the water, and the
length of time that water remains in the
treatment and distribution systems. For
this reason, and because DBF levels can
be highly variable throughout the
distribution system (as discussed in
section IV), today's proposal requires
systems to collect IDSE and Stage 2B
samples at specific locations in the
distribution system and in accordance
with a sampling schedule. For purposes
of determining the number of required
samples, EPA intends to maintain the
provision in the Stage 1 DBPR
(§ 141.132(a)(2)J that multiple wells
drawing raw water from a single aquifer
may, with State approval, be considered
one plant, and prior approvals will
remain in force unless withdrawn.
a. Stage 2A. For Stage 2A of the
proposed rule, compliance will be based
on the compliance sampling sites and
frequency established under the existing
Stage 1 DBPR. Systems must continue to
monitor for TTHM and HAAS using a
plant-based approach, as required under
40 CFR 141.132. Using these monitoring
results, systems must continue to
demonstrate compliance with Stage 1
MCLs of 0.080 mg/L for TTHM and
0.060 mg/L for HAA5, based on a
running annual average (see 40 CFR
141.133). In addition, systems must
comply with the Stage 2A MCLs of
0.120 mg/L for TTHM and 0.100 mg/L
for HAAS, based on the LRAA at each
Stage 1 DBPR monitoring location. Stage
1 DBPR provisions for systems to reduce
the frequency of TTHM and HAAS
monitoring will still apply.
Stage 2A will primarily affect surface
water systems serving at least 10,000
people or systems with multiple plants,
because these systems are required to
monitor at more than one location in the
distribution system. Most other systems
take compliance samples at only one
location under Stage 1 and in these
cases, the calculated LRAA will be
equal to the calculated RAA.
b. IDSE. IDSE monitoring
requirements are designed to identify
locations within the distribution system
with high TTHM and HAAS levels,
which will serve as Stage 2B monitoring
sites. The following discussion provides
details on the IDSE standard monitoring
program. Section V.H identifies other
approaches by which systems can meet
IDSE requirements of the rule.
For IDSE monitoring, subpart H
systems serving at least 10,000 people
must collect samples approximately
every 60 days at eight distribution
system sites per plant (these are in
addition to Stage 1 DBPR compliance
monitoring sites). The distribution
system residual disinfectant type
determines the location of the eight
sites, as shown in Table V-3.
Subpart H systems serving fewer than
10,000 people and all ground water
systems must collect IDSE samples at
two distribution system sites per plant
(at sites that are in addition to the Stage
1 DBPR compliance monitoring sites) as
shown in Table V-3. Subpart H systems
serving 500-9,999 people and ground
water systems serving at least 10,000
people must sample quarterly
(approximately every 90 days); subpart
H systems serving fewer than 500
people and ground water systems
serving fewer than 10,000 people must
sample semi-annually (approximately
every 180 days).
EPA is also proposing IDSE
monitoring requirements for
consecutive systems. For consecutive
systems that both purchase finished
water and treat source water to produce
finished water, IDSE requirements are
the same as for non-consecutive systems
with the same population and source
water type (see Table V-3}. For these
consecutive systems, each consecutive
system entry point (defined in section
V.C) is counted as one treatment plant
for purposes of determining sampling
requirements. However, the State may
allow a system to consider multiple
consecutive system entry points to be
considered a single point.
As noted previously, for consecutive
systems that purchase all of their
finished water year-round, EPA is
proposing a population-based
monitoring approach (see Table V-4)
instead of a plant-based approach.
Under the population-based approach,
monitoring requirements are not
influenced by the number of
consecutive system entry points, but are
based solely on the population served
and the type of source water used. EPA
believes the population-based approach
is equitable and will provide
representative DBP concentrations
throughout distribution systems.
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Federal Register/VoI. 68, No. 159/Monday, August 18, 2003/Proposed Rules
TABLE V-3.—PROPOSED IDSE MONITORING REQUIREMENTS
System type and population
served
Subpart H >10,000
Subpart H 500-9,999 or Ground
Water >10,000.
Subpart Any H <500 or Ground
Water <10,000.
Consecutive Systems
Distribution system disinfectant
type
Number
of moni-
toring
periods
26
26
34
24
Distribution system sample locations per plant per moni-
toring period 1
Total
8
8
2
2
Near
entry
point
2
1
0
0
Average
residence
time
2
2
0
0
High
TTHM
locations
2
3
1
1
High
HAAS
locations
2
2
1
1
—Consecutive systems that purchase 100% of their finished water
year-round — see Table V.4.
—Consecutive systems that also treat source water to produce finished
water— plant-based monitoring at same location and frequency as a
non-consecutive system with the same population and source water.
1 Samples must be taken at locations other than the existing Stage 1 DBPR monitoring locations. Dual sample sets (i.e., a TTHM and an HAAS
sample) must be taken at each site. Sampling locations should be distributed throughout the distribution system.
2 Approximately every 60 days.
3 Approximately every 90 days.
4 Approximately every 180 days.
TABLE V-4. POPULATION-BASED MONITORING FREQUENCIES AND LOCATIONS UNDER IDSE FOR CONSECUTIVE SYSTEMS
THAT PURCHASE 100% OF FINISHED WATER YEAR-ROUND
Source water type
Subpart H
Ground Water
Population size category
0-499
500-4,999
5,000-9,999
10,000-24,999
25,000-49,999
50,000-99,999
100,000-499,999
500,000-1,499,000
1,500,000-4,999,999
£5,000,000
0-499
500-9,999
10,000-99,999
100,000-499,999
£500,000
Monitoring periods and
frequency
Two 2 every 180 days) ...
Four (every 90 days)
Two (every 180 days)
Distribution system sample locations 1
Total
2
2
4
B
12
16
24
32
40
48
2
2
6
8
12
Near
entry
points 2
1
2
3
4
6
B
10
1
1
2
Average
residence
time
1
2
3
4
6
8
10
12
1
1
2
High
TTHM
locations
1
1
2
3
4
5
8
10
12
14
1
1
2
3
4
High
HAAS
locations
1
1
1
2
3
4
6
8
10
12
1
1
2
3
4
1 Samples must be taken at locations other than the existing Stage 1 DBPR monitoring locations. Dual sample sets (i.e., a TTHM and an HAAS
sample) must be taken at each site. Sampling locations should be distributed throughout the distribution system.
2 If the number of entry points to the distribution system is less than the specified number of sampling locations, additional samples must be
taken equally at high TTHM and HAA5 locations. If there is an odd extra location number, a sample at a high TTHM location must be taken If
the number of entry points to the distribution system is more than the specified number of sampling locations, samples must be taken at entry
points to the distribution system having the highest water flows.
As a part of the monitoring schedule,
all systems conducting IDSE monitoring
must collect samples during the peak
historical month for TTHM levels or
water temperature. EPA will provide
guidance to assist systems in choosing
IDSE monitoring locations, including
criteria for selecting high TTHM and
HAAS monitoring locations.
c. Stage 2B. For those systems
required to conduct an IDSE, Stage 2B
monitoring sites are based on the
system's IDSE results and Stage 1 DBPR
compliance monitoring results. For
those systems not required to conduct
an IDSE, Stage 2B monitoring locations
are based on the system's Stage 1 DBPR
compliance monitoring results and an
evaluation of the distribution system
characteristics to identify additional
monitoring locations, if required.
Consistent with the Advisory
Committee recommendations, the
monitoring frequency for Stage 2B is
structured so that systems that monitor
quarterly under the Stage 1 DBPR will
continue to monitor quarterly. In
addition, the monitoring schedule must
include the month with the highest
historical DBF concentrations.
Many systems on reduced monitoring
under the Stage 1 DBPR will conduct
Stage 2B compliance monitoring at
different or additional locations than
those used for Stage 1 compliance
monitoring. Such systems must conduct
routine monitoring for at least one year
before being eligible for reduced
monitoring under Stage 2B. Those
systems that monitor at the same
locations under both the Stage 1 DBPR
and Stage 2B DBPR and have qualified
for reduced monitoring under Stage 1
may remain on reduced monitoring at
the beginning of Stage 2B.
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49597
EPA is proposing to require all
systems to develop and maintain a DBF
monitoring plan that must include the
following information: monitoring
locations, monitoring dates, compliance
calculation procedures, and copies of
any permits, contracts, or other
agreements with third parties to sample,
analyze, report, or perform any other
monitoring requirement. Each system in
a combined distribution system (as
discussed in section V.C) must develop
and maintain its own monitoring plan.
To comply with the requirement for a
monitoring plan, systems may develop a
new plan or update the monitoring plan
required under the Stage 1 DBPR (see
§ 141.132(0). In either case, the system
must follow the monitoring plan, which
will be based on the IDSE report
submitted to the State, modified by any
changes required by the State.
Table V-5 summarizes proposed
routine and reduced monitoring
requirements for Stage 2B of today's rule
for non-consecutive systems and for
consecutive systems that also treat
source water. Tables V-6 and V—7
summarize proposed routine and
reduced Stage 2B monitoring
requirements for consecutive systems
that purchase all of their finished water
year-round. The proposed reduced
monitoring requirements are consistent
with the approach taken in the Stage 1
DBPR.
TABLE V-5.—PROPOSED STAGE 2B ROUTINE AND REDUCED MONITORING REQUIREMENTS FOR NON-CONSECUTIVE
SYSTEMS AND FOR CONSECUTIVE SYSTEMS THAT ALSO TREAT SOURCE WATER To PRODUCE FINISHED WATER 1
System size and source
water type
Subpart H systems serv-
ing >1 0,000 people.
Subpart H systems serv-
ing 500 to 9,999 peo-
ple.
Subpart H systems serv-
ing <500 people.
Ground water systems
serving £10,000 peo-
ple7.
Ground water systems
serving 500 to 9,999
people7.
Ground water systems
serving <500 people7.
Consecutive systems
that also treat source
water.
Routine monitoring (per
plant)2
Four dual sample sets
per quarter.
Two dual sample sets
per quarter3.
One dual sample set
per year56.
Two dual sample sets
per quarter3.
Two dual sample sets
per year35.
One dual sample set
per year66.
Requirements to qualify for reduced
monitoring
One year of completed routine moni-
toring and all TTHM and HAA5
LRAAs are no more than 0.040
mg/L and 0.030 mg/L, respec-
tively, and TOC running annual
average <4.0 mg/L.
One year of completed routine moni-
toring and all TTHM and HAAS
LRAAs are no more than 0.040
mg/L and 0.030 mg/L, respec-
tively, and TOC running annual
average <4.0 mg/L.
Monitoring may not be reduced
One year of completed routine moni-
toring and all TTHM and HAAS
LRAAs are no more than 0.040
mg/L and 0.030 mg/L, respectively.
One year of completed routine moni-
toring and all TTHM and HAAS
LRAAs are no more than 0.040
mg/L and 0.030 mg/L, respectively.
One year of completed routine moni-
toring and all TTHM and HAAS
LRAAs are no more than 0.040
mg/L and 0.030 mg/L, respectively.
Reduced monitoring
(per plant)
Two dual sample sets
per quarter.
Two dual sample sets
per year".
NA
Two dual sample sets
per year4.
Two dual samples every
third year4.
Two dual samples every
third year4.
Trigger for returning to
routine monitoring
TOC >4.0 mg/L as an
RAA, or TTHM LRAA
>0.040 mg/L or HAAS
LRAA >0.030 mg/L.
TOC >4.0 mg/L as an
RAA, or Single Sam-
ple of TTHM >0.060
mg/L or HAAS >0.045
mg/L.5
NA.
Single Sample of TTHM
>0.060 mg/L or HAAS
>0.045 mg/L.5
Single sample of TTHM
>0.040 mg/L or HAAS
>0.030 mg/L.5
Single sample of TTHM
>0.040 mg/L or HAAS
>0.030mg/L5
System must meet the routine and reduced monitoring requirements of a non-consecutive system with the same pop-
ulation and source water. Monitoring may be reduced to the level required of that non-consecutive system.
1 Samples must be taken during representative operating conditions. Quarterly samples must be taken approximately every 90 days.
2 Systems will use the results of their IDSEs and Stage 1 DBPR compliance monitoring to recommend Stage 2B monitoring locations rep-
resentative of high TTHM and HAAS concentrations to the State in their IDSE reports. Systems must monitor at the recommended locations un-
less the State requires other locations. .... . J . ,. ., ^ ,
3 If site and quarter of highest individual TTHM and HAAS measurement are the same, monitoring is only required at one location if State ap-
4 If site and quarter of highest individual TTHM and HAAS measurement are the same, monitoring is only required at one location.
5 If any single sample of TTHM >0.080 mg/L or HAAS >0.060 mg/L, system must go to increased monitoring of quarterly dual samples at each
routine monitoring location and can return to routine monitoring when TTHM <0.060 mg/L and HAAS <0.045 mg/L as LRAAs.
6 If the site or month of highest TTHM is not the same as the site or month of highest HAAS, the system must monitor for TTHM at the location
of the highest TTHM LRAA during the month of highest TTHM single measurement and for HAAS at the location of the highest HAAS LRAA dur-
ing the month of highest HAAS single measurement. , • _,,_,
7 Ground water systems are those not under the direct influence of surface water. For the purpose of determining the required number of sam-
ples multiple wells drawing water from a single aquifer may, with State approval, be considered one treatment plant.
i. Subpart H systems serving 10,000 or
more people.
Routine monitoring: Systems must
take four dual sample sets (i.e., a TTHM
and an HAAS sample must be taken at
each sampling site) per treatment plant
per quarter. Systems must monitor at
locations recommended in the IDSE
report, unless the State has required
other locations. Most systems must take
samples at each plant in the system as
follows: One dual sample set at the
existing Stage 1 DBPR average residence
time monitoring location with the
highest TTHM or HAAS LRAA, one
dual sample set at a point representative
of the highest HAAS levels, and two
dual sample sets at points representative
of the highest TTHM levels.
Systems must schedule monitoring so
that one quarter's monitoring is
conducted during the peak historical
month for high TTHM concentration
and the other quarterly monitoring is
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49598
Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
conducted approximately every 90 days
on a predetermined schedule included
in the system's monitoring plan.
Reduced monitoring: Only systems
with source water TOG <4.0 mg/L as an
RAA that have completed at least one
year of routine monitoring may qualify
for reduced monitoring (see Table V-5).
Systems that have a TTHM LRAA
<0.040 mg/L and an HAAS LRAA
<0.030 mg/L at all sites, in addition to
a source water TOG RAA <, 4.0 mg/L,
may reduce the monitoring frequency
for TTHM and HAAS to two dual
sample sets (one each at sites
representative of the highest HAAS and
TTHM LRAAs) per treatment plant per
quarter. Systems on a reduced
monitoring schedule may remain on
that reduced schedule as long as the
LRAA of all samples taken in the year
is no more than 0.040 mg/L for TTHM
and 0.030 mg/L for HAAS or if source
water TOG exceeds 4.0 mg/L as an RAA.
Systems must revert to routine
monitoring in the quarter immediately
following any quarter in which the
LRAA for any monitoring location
exceeds 0.040 mg/L for TTHM or 0.030
mg/L for HAAS. Additionally, the State
may return a system to routine
monitoring at the State's discretion.
Compliance determination: A PWS is
in compliance with Stage 2B when the
TTHM and HAAS LRAAs for each
sample location, computed quarterly,
are less than or equal to the Stage 2B
MCLs of 0.080 mg/L and 0.060 mg/L,
respectively. Otherwise, the system is
out of compliance.
ii. Subpart H systems serving 500 to
9,999 people. Routine monitoring;
Systems must monitor quarterly for each
treatment plant by taking two dual
sample sets, one each at sites
representative of high HAAS levels and
high TTHM levels (as recommended in
the IDSE report). However, if the State
determines that the sites representative
of the high TTHM and HAAS levels are
at the same location, the State may
determine that the system is only
required to monitor at one site per
treatment plant.
Systems must conduct quarterly
monitoring during the peak historical
month for TTHM with quarterly
samples taken approximately every 90
days on a predetermined schedule
specified in the system's monitoring
plan. All samples must be taken as duai
sample sets (j'.e., a TTHM and an HAAS
sample must be taken at each site).
Reduced monitoring: To qualify for
reduced monitoring, systems must meet
certain prerequisites (see Table V-5).
Systems eligible for reduced monitoring
may reduce the monitoring frequency
from quarterly to annually. Samples
must be taken during the month(s) of
peak historical TTHM and HAAS levels
at the same locations specified under
routine monitoring. Systems that have
their highest TTHM and HAAS levels in
the same month must take dual sample
sets at both the high TTHM and high
HAAS sites. If the high months for
TTHM and HAAS are not the same, the
system must take dual sample sets in
both the high TTHM and high HAA5
months. Systems on a reduced
monitoring schedule may remain on
that reduced schedule as long as the
annual sample taken at each location is
no more than 0.060 mg/L for TTHM and
0.045 mg/L for HAAS or if source water
TOG exceeds 4.0 mg/L as an RAA.
Systems that do not meet these levels
must revert to routine monitoring in the
quarter immediately following the
quarter in which the system exceeded
0.060 mg/L for TTHM or 0.045 mg/L for
HAAS. Additionally, the State may
return a system to routine monitoring at
the State's discretion.
Compliance determination: A PWS is
in compliance with Stage 2B when the
LRAAs of each sample location,
computed quarterly, are less than or
equal to the MCLs. Otherwise, the
system is out of compliance. If the
annual sample taken under reduced
monitoring exceeds the MCL, the system
must resume quarterly monitoring but is
not immediately in violation of the
MCL. The system is out of compliance
if the LRAA of the quarterly sample for
the past four quarter exceeds the MCL.
iii. Subpart H systems serving fewer
than 500 people. Routine monitoring:
Systems are required to sample annually
for each treatment plant at the location
with high TTHM and HAAS values
during the month of peak historical
TTHM levels. The system must take one
dual sample set at the site representative
of the high HAAS and TTHM levels (at
the Stage 1 DBPR monitoring site or as
recommended in the IDSE report),
unless the State determines that the
highest TTHM site and the highest
HAAS site are not at the same location
or are not during the same quarter. If the
State determines that the highest TTHM
and highest HAAS do not occur in the
same location, the system is required to
take two samples, an HAAS sample at
the site representative of the high HAAS
levels and a TTHM sample at the site
representative the high TTHM levels. If
the State determines that the highest
TTHM and highest HAAS do not occur
in the same quarter, the systems is
required to take one sample in the high
TTHM quarter and one sample in the
high HAAS quarter. If the annual
sample exceeds the MCL for either
TTHM or HAAS, the system must
monitor quarterly at the previously
determined monitoring locations.
Reduced monitoring: These systems
may not reduce monitoring to less
frequently than annually. Systems on
increased (quarterly) monitoring may
return to routine monitoring if the
LRAAs of quarterly samples are no more
than 0.060 mg/L for TTHM and 0.045
mg/L for HAAS.
Compliance determination: A PWS is
in compliance when the annual sample
(or LRAA of quarterly samples, if
increased or additional monitoring is
conducted) is less than or equal to the
MCL. If the annual sample exceeds the
MCL, the system must conduct
increased (quarterly) monitoring but is
not immediately in violation of the
MCL. The system is out of compliance
if the LRAA of the quarterly samples for
the past four quarters exceeds the MCL.
iv. Ground water systems serving
10,000 or more people. Routine
monitoring: Systems are required to
monitor quarterly for each treatment
plant in the system by taking two dual
sample sets, one each at sites
representative of high HAAS levels and
high TTHM levels (as recommended in
the IDSE report). However, if the State
determines that the sites representative
of the high TTHM and HAAS levels are
the same, the State may determine that
the system only has to monitor at one
site per treatment plant. One quarterly
sample must be taken during the peak
historical month for TTHM, with
subsequent quarterly samples taken
approximately every 90 days.
Reduced monitoring: To qualify for
reduced monitoring, systems must meet
certain requirements (see Table V-5).
Systems eligible for reduced monitoring
may reduce the monitoring frequency
from quarterly to annually. Samples
must be taken during the month(s) of
peak historical TTHM and HAAS levels
at the same locations specified under
routine monitoring. Systems that have
their highest TTHM and HAAS levels in
the same quarter must take dual sample
sets at both the high TTHM and high
HAAS sites. If the quarter for high
TTHM and high HAAS are not the same,
the system must take dual sample sets
in both the high TTHM and high HAAS
quarters. Systems on a reduced
monitoring schedule may remain on
that reduced schedule as long as the
annual sample taken at each location is
no more than 0.060 mg/L for TTHM and
0.045 mg/L for HAAS. Systems that do
not meet these levels must revert to
routine monitoring in the quarter
immediately following the quarter in
which the system exceeded 0.060 mg/L
for TTHM or 0.045 mg/L for HAAS.
Additionally, the State may return a
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49599
system to routine monitoring at the
State's discretion.
Compliance determination: A PWS is
in compliance with Stage 2B when the
locational running annual average of
sach sample location, computed
quarterly, is less than or equal to the
MCL. Otherwise, the system is out of
;ompliance. If the annual sample
xceeds the MCL, the system must
conduct increased (quarterly)
monitoring but is not immediately in
violation of the MCL. The system is out
jf compliance if the LRAA of the
quarterly sample for the past four
quarter exceeds the MCL.
v. Ground water systems serving
:ewer than 10,000 people. Routine
nonitoring: Systems serving 500 to
3,999 people are required to take two
lual sample sets annually, one each at
sites representative of high HAAS levels
uid high TTHM levels (as
•ecommended in the IDSE report).
However, if the State determines that
he sites representative of the high
CTHM and HAAS levels are the same,
he State may allow the system to
nonitor at only one site per treatment
:>lant. If the State makes a determination
hat high TTHM and high HAAS occur
n different quarters, the system must
nonitor accordingly. If the annual
;ample exceeds the MCL for either
PTHM or HAAS, the system must
nonitor quarterly at the previously
letermined monitoring locations.
Systems serving fewer than 500
jeople are required to take one dual
;ample set at the site representative of
>oth high HAAS and TTHM levels,
mless the State determines that the
ligh TTHM site and the high HAAS site
are not at the same location. If the State
makes this determination, the system is
required to take samples at two
locations, an HAAS sample at the site
representative of the high HAAS levels
and a TTHM sample at the site
representative of the high TTHM levels.
If the State makes a determination that
high TTHM and high HAAS occur in
different quarters, the system must
monitor accordingly. If the annual
sample exceeds the MCL for either
TTHM or HAAS, the system must -
monitor quarterly at the previously
determined monitoring locations.
Reduced monitoring: To qualify for
reduced monitoring, systems must meet
certain prerequisites (see Table V-5).
Systems eligible for reduced monitoring
may reduce the monitoring frequency
for TTHM and HAAS to every third
year. Systems are required to take two
water samples, at sites representative of
high HAAS and TTHM levels (as
discussed under routine monitoring)
during the month of peak TTHM levels.
Systems on a reduced monitoring
schedule may remain on that reduced
schedule as long as the sample taken
every third year is no more than 0.040
mg/L for TTHM and 0.030 mg/L for
HAAS. Systems that do not meet these
levels must resume routine annual
monitoring until their annual average is
no more than 0.040 mg/L for TTHM and
0.030 mg/L for HAAS.
Compliance determination: A PWS is
in compliance when the annual sample
(or LRAA of quarterly samples, if
increased or additional monitoring is
conducted) is less than or eqxial to the
MCL. If the annual sample exceeds the
MCL, the system must conduct
increased (quarterly) monitoring but is
not immediately in violation of the
MCL. The system is out of compliance
if the LRAA of the quarterly samples for
the past four quarters exceeds the MCL.
vi. Consecutive systems. Routine
monitoring: Monitoring requirements
are determined by whether the
consecutive system purchases all of its
finished water year-round or also treats
source water, along with the population
served and source water type of the
wholesale system (unless the
consecutive system also has a surface
water or ground water under the direct
influence of surface water {GWUDI}
source and the wholesale system is only
ground water, in which case the
consecutive system is classified as a
subpart H system). Section V.C. of
today's document provides a more
detailed discussion of consecutive
system issues.
As noted earlier, for consecutive
systems that purchase all their finished
water year-round, EPA is proposing
population-based monitoring. The
proposed number of monitoring
locations is based on the source water
type of the wholesale system and
consecutive system population.
Proposed Stage 2B compliance
monitoring requirements for
consecutive systems that purchase all
their finished water are contained in
Table V—6. Consecutive systems that
also treat source water to produce
finished water must monitor at the same
locations and same frequency as a non-
consecutive system with the wholesale
system's source water type and the
consecutive system's population.
TABLE V-6.—PROPOSED POPULATION-BASED ROUTINE MONITORING ROUTINE FREQUENCIES AND LOCATIONS UNDER
STAGE 2B FOR CONSECUTIVE SYSTEMS THAT PURCHASE ALL THEIR FINISHED WATER YEAR-ROUND
Source water type
Population size category
0-499
500-4,999
5,000-9,999
10,000-24,999
25,000-49,999
50,000-99,999
100,000-499,999
500,000-1,499,000
1,500,000-4,999,999
£5 000000
0-499
500-9,999
10,000-99,999
100,000-499,999
>500.000
Monitoring
frequency 1
oer Quarter
Distribution system sample location 2
Total
24
24
2
4
6
8
12
16
20
24
24
2
4
6
8
Highest
TTHM
locations
1
1
1
2
3
4
6
8
10
12
1
1
2
3
4
Highest
HAAS
locations
1
1
1
1
2
2
3
4
5
6
1
1
1
2
2
Existing
stage 1
compliance
locations 3
1
1
2
3
4
5
6
1
1
2
1 All systems must take at least one dual sample set during month of highest DBP concentrations. Systems on quarterly monitoring must take
ual sample sets approximately every 90 days.
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Federal Register/Vol. 68. No. 159/Monday, August 18, 2003/Proposed Rules
raS6d .°n S^tem F^^SSS"? L^8*"6 2B mooring locations in IDSE report to the State, unless State requires different or
l locations. Locations should be distributed through distribution system to the extent possible um«»i« w
a Alternate between highest HAAS LRAA and highest TTHM LRM locations among the existing Stage 1 compliance locations. If the number of
WqhertnfflJuwSl I'06 fSf ?DSEer specified number for Stage 2B, alternate between highest HAAS LRAA locations and
"System is required to take individual TTHM and HAAS samples at the locations with the highest TTHM and HAAS concentrations, respec-
tively. Only one location with a dual sample set per monrtonng period is needed if highest TTHM and HAAS concentrations occur at the same
lOCdtion.
Reduced monitoring: Consecutive
systems can qualify for reduced
monitoring if the LRAA at each location
is £0.040 mg/L for TTHM and <0.030
mg/L for HAAS based on at least one
year of monitoring at Stage 2B locations.
Consecutive systems that purchase all of
their finished water year-round may
reduce their monitoring as specified in
Table V-7. Consecutive systems that
also treat source water to produce
finished must conduct reduced
monitoring at the same locations and
same frequency as a non-consecutive
system with the wholesale system's
source water type and the consecutive
system's population.
TABLE V-7.—REDUCED MONITORING FREQUENCY FOR CONSECUTIVE SYSTEMS THAT BUY ALL THEIR WATER
Population served
Reduced monitoring frequency and location
Subpart H systems
Monitoring may not be reduced.
500 to 4,999 1 TTHM and 1 HAAS sample per year at different locations or during different quarters if the highest TTHM and
HAAS occurred at different locations or different quarters or 1 dual sample per year if the highest TTHM and
HAA5 occurred at the same location and quarter.
5,000 to 9,999 2 dual sample sets per year; one at the location with the highest TTHM single measurement during the quarter
that the highest single TTHM measurement occurred, one at the location with the highest HAAS single meas-
urement during the quarter that the highest single HAAS measurement occurred.
10,000 to 24,999 2 dual sample sets per quarter at the locations with the highest TTHM and highest HAAS LRAAs
t0 ™ ;55 2 dua' Sample sets per quarter at the locations w'th the h'9hest TTHM and highest HAAS LRAAs.
?nJ?S 4 dual samP|e sets Per quarter * the locations with the two highest TTHM and two highest HAAS LRAAs
7 ?£ 4 ^ua} samP|e sets P& quarter at the locations with the two highest TTHM and two highest HAAS LRAAs
. "7 n^^L 6 dual sample sets per quarter at the locations with the three highest TTHM and three highest HAAS LRAAs
K n™™ 4'999'999 6 dual samP|e sets Per quarter at tfie locations with the three highest TTHM and three highest HAAS LRAAs
>=5,000,000 e dual sample sets per quarter at the locations with the four highest TTHM and four highest HAAS LRAAs.
Ground water systems
<50° 1 T™1^ and 1 HAA5 sample every third year at different locations or during different quarters if the highest
TTHM and HAAS occurred at different locations or different quarters or 1 dual sample every third year if the
highest TTHM and HAAS occurred at the same location and quarter.
500 to 9,999 1 TTHM and 1 HAA5 sample every year at different locations or during different quarters If the highest TTHM and
HAAS occurred at different locations or different quarters or 1 dual sample every year if the highest TTHM and
HAAS occurred at the same location and quarter.
10,000 to 99,000 2 dual sample sets per year; one at the location with the highest TTHM single measurement during the quarter
that the highest single TTHM measurement occurred and one at the location with the highest HAAS single
measurement during the quarter that the highest single HAA5 measurement occurred
? =nn J£1'499'999 2 dual samP|e sets Per quarter; at the locations with the highest TTHM and highest HAAS LRAAs
£1,500,000 4 dual sample sets per quarter; at the locations with the two highest TTHM and two highest HAAS LRAAs.
Systems may remain on reduced
monitoring as long as the TTHM LRAA
£0.040 mg/L and the HAAS LRAA
<0.030 mg/L at each monitoring location
for systems with quarterly reduced
monitoring. If the LRAA at any location
exceeds either 0.040 mg/L for TTHM or
0.030 mg/L for HAAS or if the source
water annual average TOC level, before
any treatment, exceeds 4.0 mg/L at any
of the system's treatment plants treating
surface water or ground water under the
direct influence of surface water, the
system must resume routine monitoring.
For systems with annual or less frequent
reduced monitoring, systems may
remain on reduced monitoring as long
as each TTHM sample <0.060 mg/L and
each HAAS sample
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
49601
presents the basis for these
requirements.
a. Sampling intervals for quarterly
monitoring. Today's proposal requires
systems conducting routine quarterly
monitoring to sample approximately
every 90 days. This provision modifies
the approach used in the 1979 TTHM
rule and the Stage 1 DBPR, which
requires certain systems to conduct
monitoring based on calendar quarters.
When systems are required to monitor
based on calendar quarters, systems can
choose to cluster samples during times
of the year when DBF levels are lower
(DBFs tend to form more slowly in
colder water temperatures). For
example, a system could sample in
December (at the end of the fourth
quarter) and again in January (at the
beginning of the first quarter) when the
water is the coldest and sample in April
(at the beginning of the second quarter)
and September (at the end of the third
quarter) at either end of the hot summer
months.
To address the concern with systems
not sampling during months with the
highest DBF levels, EPA is proposing to
require systems to monitor during the
month of highest historical DBF
concentrations and require that systems
monitor approximately every 90 days.
EPA believes that this new monitoring
trategy will improve public health
protection because systems will be
•equired to monitor when high DBF
evels are expected, and the LRAA will
setter reflect actual exposure during the
/ear.
b. Reduced monitoring frequency.
Foday's proposal contains provisions
illowing reduced routine monitoring
Afhen certain criteria are fulfilled
shown in Table V-5 and V-7). EPA
jelieves that more stringent standards
ire necessary to ensure public health
srotection when systems reduce the
requency of their DBF monitoring.
Jnder the reduced monitoring
>rovisions, systems must collect
lamples during the months of highest
DBF occurrence. For systems sampling
innually under the reduced monitoring
>rovisions, EPA believes that public
lealth protection would likely be
insured throughout the year if the high
ralues are known to be below 0.060 mg/
. for TTHM and 0.045 mg/L for HAAS.
iystems monitoring every three years
nust maintain single samples under
.040 mg/L for TTHM and 0.030 mg/L
or HAAS to ensure adequate public
lealth protection over the course of the
tiree years.
c. Different IDSE sampling locations
y disinfectant type. Today's proposal
ontains different requirements for IDSE
lonitoring locations based on the
disinfectant residual used in the
distribution system. Systems that use
chloramines are required to select more
near-entry point monitoring sites for the
IDSE than chlorinated systems of
similar size and source water type. This
is due to differences in DBF formation
under chloraminated and chlorinated
conditions. Chloramine residuals are
more stable than chlorine residuals and
do not react as readily with organic
compounds in the water. Based on
evaluation of Information Collection
Rule data, DBF concentrations in
chloraminated systems vary less
throughout the distribution system than
in chlorinated systems. HAAS, in
particular, can peak at or near the entry
point to the distribution system in a
chloraminated system (USEPA 2003o).
d. Population-based monitoring
requirements for certain consecutive
systems. While the Advisory Committee
recommended basic principles for how
consecutive systems should be
regulated, it did not recommend how
EPA should explicitly address some of
the unique situations that pertain to
consecutive systems. In this regard,
consecutive systems that purchase all of
their finished water year-round are
different than other systems in that they
do not have a treatment plant. Rather,
these systems often receive water from
multiple wholesale systems or through
multiple consecutive system entry
points on a seasonal or intermittent
basis. Because a plant-based monitoring
approach (which counts treated water
distribution system entry points from
different entities as plants) would be
very difficult to implement for
consecutive systems that purchase all of
their finished water year-round, EPA is
proposing a population-based approach
for such systems.
Under a population-based approach,
the frequency of monitoring is based on
the population served and remains the
same regardless of how many entities
are providing water to the consecutive
system at different times of the year.
The population categories and
associated monitoring frequencies in
Tables V-4 and V-6 for IDSE and Stage
2B routine monitoring reflect EPA's
consideration that distribution system
complexity generally increases as the
population served grows. Increasing
distribution system complexity warrants
more monitoring to represent DBF
occurrence.
EPA developed the proposed
population-based monitoring
requirements in accordance with certain
guidelines. These are stated as follows:
—The sampling frequency for surface
water systems should be greater than
for ground water systems. The basis
for this is that, in general, systems
using surface water or mixed source
water supplies are likely to
experience higher and more variable
DBP occurrence over time than
systems using ground water
exclusively.
—Smaller systems should be allowed to
monitor less frequently per location
than larger systems because their
distribution systems are generally less
complex and monitoring costs on a
per capita basis are much higher.
—For systems using surface water, the
ratio of IDSE sample locations to the
number of routine sample locations
required for Stage 2B should be
approximately 2:1 (consistent with
Advisory Committee
recommendations for plant-based
monitoring). IDSE sampling is
intended to identify distribution
system locations with high DBP levels
and should, therefore, be more
thorough than routine monitoring.
—Because ground water systems have
much less variable DBP levels within
the distribution system than surface
water systems (see section IV), a
smaller number of additional IDSE
monitoring locations is warranted.
—Distribution system sampling
locations should be approximately
consistent with the proposed plant-
based approach as recommended by
the Advisory Committee. This will
capture the locations with the high
TTHM and HAAS LRAAs identified
in the IDSE, but also include Stage 1
compliance locations with high
TTHM and HAAS for historical
tracking.
Consistent with the first two
guidelines, the proposed population-
based monitoring requirements
maintain the same monitoring frequency
per sample location as proposed under
the plant-based approach. The following
subsection provides further discussion
of the population-based approach as it
might apply to all systems.
3. Request For Comment
EPA is requesting comments on the
proposed monitoring requirements. This
subsection begins with a list of specific
questions related to the proposed
requirements for IDSE and Stage 2B
monitoring. This is followed by a
discussion of issues associated with
plant-based monitoring requirements
and a request for comment on potential
approaches to address these issues,
including the extension of population-
based monitoring requirements to all
systems under the Stage 2 DBPR.
a. Proposed IDSE and Stage 2B
monitoring requirements. EPA is
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
requesting comment on a number of
specific aspects of the proposed
monitoring requirements.
—Should EPA require all systems that
are on reduced monitoring to revert to
routine monitoring during the IDSE
monitoring period to allow for more
data to be evaluated in the IDSE
report to better select Stage 2B
monitoring locations? Or should EPA
require a system to be on routine
monitoring during the IDSE
monitoring period in order to be
eligible for an IDSE waiver? What
limitations, if any, should EPA put on
system eligibility for an IDSE waiver?
—Should EPA require different IDSE
monitoring locations for subpart H
systems based on the residual
disinfectant (chlorine or chloramines)
in light of the possible difficulties for
implementation and data
management? Should EPA specify
monitoring locations in the rule
language for samples intended to
represent exposure for people in high-
rise buildings? Should monitoring
location selection be addressed in
guidance? Where should these
locations be so that they are truly
representative of the levels of DBFs in
water actually being consumed in
these kinds of structures?
—Is a population-based monitoring
approach (instead of a plant-based
monitoring approach) for consecutive
systems that purchase all of their
finished water year-round appropriate
and, if so, is the population-based
approach proposed today adequate?
EPA solicits comment on the
significance of monitoring and
implementation issues such as common
aquifer determinations, consecutive
system entry point determinations,
seasonal plants, and monitoring
inequities, and whether the proposed
monitoring requirements should be
modified, EPA also solicits comment on
modifying the proposed monitoring
requirements to address these issues, in
part, with provisions such as the
following;
—Should EPA set a limit on the
maximum number of IDSE and
routine monitoring samples that could
be required? Should this limit be
different for systems using ground
water or surface water or mixed
systems? For different system size
categories? What rationale should be
used to specify maximum sample
numbers?
—Should a provision be included that
would allow States to reduce the
sampling frequency, beyond those
currently proposed (i.e., common
aquifer determinations and low DBF
levels)? If so, should specific criteria
for systems to qualify for State
approval of reduced monitoring be
specified in the rule?
—What, if any, criteria should be set by
which systems with very large
distribution systems but few plants
would be required to conduct
additional IDSE or routine
monitoring, beyond that currently
proposed?
—For subpart H mixed systems, should
States be given discretion to reduce
routine compliance monitoring
samples intended to represent ground
water sources, since such sources
typically have lower precursor levels
and produce lower DBF
concentrations?
—Should EPA allow or require systems
to reallocate plant-based IDSE
monitoring locations from small
plants to large plants? From plants
with better water quality (based on
expected lower DBF formation) to
poorer water quality? What criteria
should be used?
b. Plant-based vs. population-based
monitoring requirements. The proposed
monitoring requirements incorporate a
plant-based approach for all systems
other than consecutive systems that
purchase all of their finished water year-
round. The plant-based approach was
adopted from the 1979 TTHM Rule and
the Stage 1 DBPR and derives from the
assumption that as systems increase in
size, they will tend to have more plants
(with different sources and treatment)
and increased complexity. This
warrants increased monitoring to
represent DBF occurrence in the
distribution system.
EPA has identified a number of issues
related to the use of a plant-based
monitoring approach under the Stage 2
DBPR. The following discussion
presents these issues and solicits
comment on approaches to address
them, including the use of population-
based monitoring requirements.
i. Issues with plant-based monitoring
requirements. One issue with a plant-
based monitoring approach is that it can
result in disproportionate monitoring
requirements for systems serving the
same number of people. This occurs
because the required number of
sampling sites increases with the
number of plants that feed disinfected
water into a distribution system.
Consequently, some systems, depending
upon their size, the number of treatment
plants, and the nature of their
distribution system, will be required to
collect relatively large or small numbers
of TTHM and HAAS samples relative to
their population served.
Table V-8 reflects EPA estimates of
the number of plants per system by
system size category for systems using
ground water and subpart H systems.
Subpart H systems include systems that
use ground water as a source because
under the proposal, ground water plants
in subpart H systems are treated as
surface water plants for purposes of
determining monitoring requirements.
While the proposed plant-based
requirements distinguish sampling
requirements by three systems sizes
(<500 people, 500-9999 people, and
10,000 or more people), Table V-8
includes additional size categories to
reflect the potential inequities in
sampling requirements among different-
sized systems.
TABLE V-8.-—NUMBER OF TREATMENT PLANTS PER SYSTEM (BASED ON DATA FROM 1995 CWSS (1))
Source water type
Subpart H
Ground Water
Population served
0-499
500-4,999
5,000-9,999
10,000-24,999
25,000-49,999
50,000-99,999
100,000-499,999 ...
£500,000
0-499
500-9.999
No. of sys-
tems in
database
124
146
64
59
46
76
51
23
181
332
No, of treatment plants per system
10th
percentile
1
1
1
1
1
1
1
2
1
1
Median
1
1
1
1
1
2
2
4
1
1
Mean
1.4
1.3
1.7
2.0
2.2
3.4
3.0
5.8
1.4
1 ft
90th
percentile
2
2
3
3
4
6
5
10
3
95th
percentile
3
3
4
4
6
12
10
13
4
Maximum
5
6
6
18
9
34
21
56
11
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49603
TABLE V-8.— NUMBER OF TREATMENT PLANTS PER SYSTEM (BASED ON DATA FROM 1995 CWSS (1))—Continued
Source water type
Population served
10,000-99,999
£100,000
No. of sys-
tems in
database
128
21
No. of treatment plants per system
10th
percentile
1
1
Median
4
3
Mean
4.2
9.9
90th
percentile
9
31
95th
percentile
11
32
Maximum
18
33
(1) Results from analysis of 1995 CWSS data (Question Q18). The analysis uses a statistical bootstrapping approach to generate the number
of plants per system. Details of this analysis are described in the 2002 revisions to the Model Systems Report [to be published]. The maximums
reflect the maximum number of plants per system among the respondents to the 1995 CWSS. Since the 1995 CWSS database only reflects a
fraction of all the systems in the respective size categories, some systems are likely to have a higher number of plants per system than the
maximums listed in this table.
Noteworthy in Table V-8 are the wide
ranges of number of plants per system
in the various size categories for both
ground water and surface water systems
and, consequently, the wide range of
potential monitoring implications. Since
the number of treatment plants directly
influences the number of samples
required, systems serving the same
number of people may have more than
a 10-fold difference in required
sampling, depending on the numbers of
plants in their systems. For example,
Table V-8 indicates that for ground
water systems serving at least 10,000
people, at least 10% of the systems had
only one treatment plant, while 10%
(90th percentile) had 10 or more
treatment plants.
While Table V-8 does not take into
account factors that may reduce
monitoring requirements, such as
common aquifer determinations, EPA
believes these data indicate that DBF
sampling requirements based on the
number of water treatment plants per
system may be excessive for many
systems. This is particularly the case for
those systems with many ground water
plants, since their DBF levels are often
low and relatively stable.
Conversely, for other systems, such as
large surface water systems with one
plant, plant-based monitoring
requirements may not require enough
samples to fairly represent DBF
occurrence in the distribution system.
For example, under the plant-based
approach, a system with only one plant
serving 100,000—499,000 people would
have the same sampling requirements as
a system with one plant serving 11,000
people. The larger of these two systems
is likely to have much more pipe length
and other complex factors influencing
DBF formation (such as number of
storage tanks or booster chlorination
points in the distribution system). Also,
systems with multiple plants must take
the same number of samples per plant,
even if one plant provides a much
higher percentage of the water than
another.
Another issue with plant-based
monitoring requirements is when plants
or consecutive system entry points are
operated seasonally or intermittently. A
monitoring location that represents a
plant or entry point during a monitoring
period when it is in operation will not
be representative when that plant or
entry point it is not in operation.
A third issue is requirements for
consecutive systems. For consecutive
systems that also treat source water to
produce finished water, each
consecutive system entry point is
considered a treatment plant for the
purpose of determining monitoring
requirements, except when the State
allows multiple entry points to be
treated as a single plant (see section V.C.
for further discussion). Each entry point
is treated as a separate plant to
recognize different source waters and
treatment (resulting in different DBF
levels) from the wholesale system(s) and
the treatment plants(s) operated by the
consecutive system. However, under
this plant-based approach, State
determinations of monitoring
requirements for consecutive systems
will be complicated, especially in large
combined distribution systems with
many connections between systems.
ii. Approaches to addressing issues
with plant-based monitoring. EPA is
requesting comment on two approaches
to address the issues with plant-based
monitoring requirements described in
this subsection. One approach is to keep
the proposed plant-based monitoring
approach and add new provisions to
address specific concerns. Another
approach is to base monitoring
requirements on population served in
lieu of the number of water treatment
plants per system. The following
paragraphs describe each approach.
EPA could maintain a plant-based
monitoring approach and try to address
the related issues described in this
subsection through modifying the
proposed monitoring requirements with
provisions like the following:
—Set a limit on the maximum number
of IDSE and routine monitoring
samples that could be required. EPA
believes that this limit should be
different for systems using ground
water or surface water or mixed
systems and for different system size
categories. However, the Agency has
not developed a rationale to specify
maximum sample numbers for
specific system categories.
—Include a provision that would allow
States to reduce the required number
of samples for reasons other than
those currently proposed (i.e.,
common aquifer determinations and
low DBF levels). EPA would have to
develop specific criteria in the rule for
systems to qualify for State approval
of reduced monitoring. For example,
in subpart H mixed systems, States
could be given discretion to reduce
routine compliance monitoring for
ground water sources, since such
sources typically have lower DBF
concentrations.
—Develop criteria by which systems
with very large distribution systems
but with few plants would be required
to conduct additional IDSE or routine
monitoring in order to better
characterize DBF exposure throughout
the distribution system.
These provisions would allow for
some issues to be addressed, but would
make implementation complex and
could add a significant burden to States.
An alternative approach to addressing
the issues with plant-based monitoring
requirements is to apply population-
based monitoring requirements to all
systems. Under a population-based
monitoring approach, the total system
population served and the source water
type would determine the number of
IDSE and routine monitoring samples
taken. Monitoring requirements would
not be based on the number of plants
per system or consecutive system entry
points. States would not be required to
make common aquifer determinations or
address whether plants are combined
into a single pipe prior to entering the
distribution system.
Proposed population-based
monitoring requirements for
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consecutive systems that purchase all
their finished water year-round are
shown in Tables V-4, V-6, and V-7.
Also, the proposed rule language in
subparts U and V contains requirements
for population-based monitoring similar
to what might be required for all
systems. EPA believes that through
using a broader array of system size
categories than under the plant-based
approach, population-based monitoring
could result in an equitable
proportioning of DBF sampling
requirements. Tables V-9 and V-10
•compare the proposed numbers of
sampling locations per system under a
population-based approach with a
plant-based approach, using the median
and mean number of plants per system
given in Table V-8 for each of the size
categories. For surface water systems,
the median provides a better indicator
of the typical number of required
sampling locations under the plant-
based approach because it is much less
sensitive to systems with a very large
number of plants.
TABLE V-9.—COMPARISON OF MONITORING LOCATIONS PER SYSTEM UNDER IDSE FOR PLANT-BASED AND POPULATION-
BASED APPROACHES
Source water type
Subpart H
Ground Water
Population size category
0-499 ..
500-4,999
5,000-9,999
10,000-24,999
25,000-49,999
50,000-99,999
100,000-499,999
500,000-1,499,000
1,500.000-4,999,999
£5,000,000
0-499
500-9,999
10,000-99,999
100,000-499,999
>500,000
Number
of sam-
pling
periods
2
4
4
6
6
6
6
6
2
2
4
4
Plant-based
Number of
monitoring lo-
cations per
plant1
2
2
2
8
8
B
8
8
2
2
2
2
Number of monitoring locations per
system
Based on me-
dian number of
plants per
system 2
2
2
2
8
8
16
16
32
2
2
8
6
Based on mean
number of plants
per system 2
3
3
3
16
18
27
24
46
2
4
9
20
Population-based
Number of moni-
toring locations
per system 3
2
2
4
B
12
16
24
32
40
48
2
2
6
8
12
1 From Table V-5.
2 Calculated from the number of locations per plant multiplied by number of plants per system (Table V-81
3 From Table V-4.
TABLE V-10.—COMPARISON OF ROUTINE MONITORING LOCATIONS PER SYSTEM UNDER STAGE 2B FOR PLANT-BASED
AND POPULATION-BASED APPROACHES
Source water type
Subpart H
Ground Water
Population size category
0-499
500-4,999
5,000-9,999
10,000-24,999
25,000-49,999
50,000-99,999
100,000-499,999
500,000-1,499,000
1,500,000-4,999,999
S5.000.000
0-499
500-9,999
10,000-99,999
100,000-499,999
>500,000
Frequency
of
monitoring
1
4
4
4
4
4
4
4
1
1
4
4
Plant-based
Number of
monitoring lo-
cations per
plant 1
1
2
2
4
4
4
4
4
1
2
2
2
Number of monitoring locations per
system
Based on me-
dian number of
plants per
system 2
1
2
2
4
4
8
8
16
1
2
8
6
Based on mean
number of plants
per system 2
1
3
3
8
9
14
12
23
1
4
9
20
Population-based
Number of moni-
toring locations
per system 3
2
2
2
4
6
8
12
16
20
24
2
2
. . 4
6
8
1 From Table V-5.
2 Calculated from the number of locations per plant multiplied by number of plants per system (Table V-8)
3 From Table V-6. ''
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49605
Under the population-based
ipproach, the number of required
sampling locations for systems of
lifferent size and source water type
ipproximates the number of sampling
ocations that would be required for the
najority of systems under the plant-
>ased approach. However, systems in
he tail ends of the distribution of
lumber of plants per system would be
•equired to take more or fewer samplers
ban under the plant-based approach.
CPA used the median number of plants
n a given size category as the primary
lasis for establishing the number of
nonitoring locations for the population-
)ased approach.
EPA adjusted the number of sampling
ocations for systems in population sizes
15,000 to 49,999, 100,000-499,999, and
Beater than 1,500,000 to provide a more
jven upward trend in proportion to
)opulation increase. Consistent with the
>lant-based approach, ground water
ystems serving 10,000 people or greater
vould be required to sample at
ipproximately Vs to Vz the frequency
equired for surface water systems
mder the population-based approach.
EPA suggests that the monitoring
requencies for the IDSE and Stage 2B
:ompliance proposed for consecutive
ystems that purchase all of their
inished water year-round (as presented
n Tables V-4 and V-6) are appropriate
or all systems if a population-based
.pproach were used in lieu of a plant-
tased approach in the final rule. EPA
telieves that the population-based
pproach would ensure more equal and
ational monitoring requirements among
ystems serving similar populations
han the plant-based approach does,
vhile providing generally improved
epresentation of DBF occurrence
droughout the distribution system.
luch an approach would simplify
mplementation and reduce
ransactional costs to States by
acilitating determination of the number
f sampling locations.
To further evaluate the potential
mplications of monitoring under the
opulation-based approach, EPA has
prepared an economic analysis
addressing monitoring impacts using
the population-based approach
(Economic Analysis for the Stage 2
DBPR, EPA 2003i) and guidance on how
plant-based monitoring requirements
would be affected if a population-based
approach were used instead (Draft IDSE
Guidance Manual, EPA 2003J).
EPA requests comments on alternative
DBF monitoring requirements that are
population-based versus plant-based;
specifically on the merits of a
population-based monitoring approach
for all systems for the purpose of
addressing the issues raised in this
section. Specifically:
—Should alternative system size
categories be specified under the
suggested population-based
approach?
—What potential issues might be unique
for a population-based monitoring
approach and how might they be
addressed?
—Should alternative numbers of
monitoring locations or frequencies be
required in the IDSE or for Stage 2B
monitoring?
—Are reduced monitoring requirements
adequate to ensure continued
protection relative to the MCL?
—What are the transition costs and
issues associated with moving from a
plant-based to a population based
approach and how might they be
addressed?
/. Compliance Schedules
1. What is EPA Proposing?
Today's proposed rule establishes
compliance deadlines for public water
systems to implement the requirements
in this rulemaking. EPA is proposing a
phased strategy for MCLs and
simultaneous compliance with the
LT2ESWTR consistent with the
recommendation of the M-DBP
Advisory Committee and to comply
with SDWA requirements for risk
balancing. Central to the determination
of these deadlines is the principle of
simultaneous compliance between the
FIGURE V-2. SCHEDULE EXAMPLES
Stage 2 DBPR and the LT2ESWTR,
which will ensure continued microbial
protection as systems implement
changes to decrease DBF levels and
minimize risk-risk tradeoffs.
IDSE schedule. Subpart H and ground
water systems covered by today's
proposed rule that serve a population of
10,000 or more must submit the results
of their IDSE to the primacy agency two
years after rule promulgation. In
addition, wholesale or consecutive
systems serving fewer than 10,000 that
are part of a combined distribution
system with at least one system serving
>10,000 must meet this same schedule.
These systems must begin IDSE
monitoring early enough to collect and
analyze 12 months of data and prepare
an IDSE report, which includes
recommendations for Stage 2B
monitoring locations (see section V.H).
Subpart H and ground water systems
covered by today's proposed rule that
serve a population of fewer than 10,000
(except those noted before) must submit
the results of their IDSE to the primacy
agency four years after rule
promulgation. These systems must
begin IDSE monitoring early enough to
collect and analyze the data and prepare
the IDSE report.
Stage 2A schedule. All systems must
comply with the Stage 2A MCLs for
TTHM and HAA5 three years after rule
promulgation.
Stage 2B schedule. Systems required
to submit an IDSE report due two years
after the rule is promulgated must
comply with Stage 2B six years after
rule promulgation. Subpart H systems
required to submit IDSE reports four
years after rule promulgation and
required to do Cryptosporidium
monitoring under the LT2ESWTR must
comply with Stage 2B 8.5 years after
rule promulgation. Small systems not
required to Cryptosporidium monitoring
must be in compliance with Stage 2B
7.5 years after rule promulgation. Figure
V-2 contains several examples of how
to determine IDSE and Stage 2B
compliance dates.
—Wholesale system (pop. 64,000) with three consecutive systems (pops. 21,000; 15,000; 5,000):
—IDSE report due for all systems two years after promulgation since wholesale system serves at least 10,000
—Stage 2B compliance beginning six years after promulgation for all systems
—Wholesale system (pop. 4,000) with three consecutive systems (pops. 21,000; 5,000; 5,000):
—IDSE report due for all systems two years after promulgation since one consecutive system in combined distribution system serves at
least 10,000
—Stage 2B compliance beginning six years after promulgation for all systems
—Wholesale system (pop. 4,000) with three consecutive systems (pops. 8,000; 5,000; 5,000):
—IDSE report due for all systems four years after promulgation since no system in combined distribution system exceeds 10,000 (even
though total population exceeds 10,000)
—Stage 2B compliance beginning 7.5 years after promulgation if no Cryptosporidium monitoring under the LT2ESWTR is required or be-
ginning 8.5 years after promulgation if Cryptosporidium monitoring under the LT2ESWTR is required
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
2. How Did EPA Develop This Proposal?
EPA is proposing provisions for
simultaneous rule compliance with the
LT2ESWTR to maintain a balance
between DBF and microbial risks.
Simultaneous compliance was
mandated by the 1996 SDWA
Amendments which require that EPA
"minimize the overall risk of adverse
health effects by balancing the risk from
the contaminant and the risk from other
contaminants, the concentrations of
which may be affected by the use of a
treatment technique or process that
would be employed to attain the
maximum contaminant level" (Sec.
If systems were required to comply
with the Stage 2 DBPR prior to the
LT2ESWTR, systems could lower their
disinfectant dose or switch to a less
effective disinfectant in an attempt to
decrease DBF levels. This practice could
leave segments of the population
exposed to greater microbial risks.
Therefore, simultaneous compliance
was a consensus recommendation of the
Stage 2 M-DBP Advisory Committee to
ensure that systems would not
compromise microbial protection while
attempting to meet more stringent DBF
requirements.
The Advisory Committee supported
the Initial Distribution System
Evaluation, as discussed in section V.H,
and EPA is proposing an IDSE schedule
consistent with the Advisory
Committee's recommendations, in
which systems are required to submit
their IDSE reports to the State either two
or to four years following rule
promulgation. The Advisory Committee
recommended this to allow enough time
for the State to review (and revise, if
necessary) systems' recommendations
for Stage 2B monitoring locations and to
allow systems three years after
completion of the State review to
comply with Stage 2B MCLs as LRAAs
at Stage 2B monitoring locations.
This schedule requires systems
serving >10,000 people and smaller
wholesale and consecutive systems that
are part of a combined distribution
system that includes at least one system
serving >10,000 to complete IDSE
monitoring and prepare and submit the
IDSE report two years after the rule is
finalized. This requirement for
wholesale systems and consecutive
systems serving fewer than 10,000 that
are part of a combined distribution
system with at least one system serving
at least 10,000 to conduct an "early
IDSE" allows the wholesale system to be
aware of compliance challenges facing
the consecutive system and to
implement treatment plant capital and
operational improvements as necessary
to ensure compliance. The Advisory
Committee and EPA both recognized
that DBFs, once formed, are difficult to
remove and are generally best addressed
by treatment plant improvements.
While this schedule allows for
systems to have the three years to
comply with Stage 2B following State
review of the IDSE report, it begins prior
to States being required to obtain
primacy to implement the IDSE. States
have two years from promulgation to
adopt and implement new regulations
and may request a two year extension.
While EPA is preparing to support
implementation of those IDSE
requirements that must be completed
prior to States achieving primacy,
several States have expressed concern
about EPA providing guidance and
reviewing reports from systems that the
State has permitted, inspected, and
worked with for a long time. These
States believe that their familiarity with
the systems enables them to make the
best decisions to implement the rule
and protect public health.
As specific rule requirements were
developed and implementation
schedules and resource burdens
determined, States also expressed
concerns about the challenges that early
implementation posed. In response to
these concerns, EPA has developed
several alternatives to the IDSE schedule
and provisions that may meet the goals
of the IDSE, but allow for greater State
involvement, lower implementation
burden, and no delay of the public
health protection assured by compliance
with Stage 2B.
The first, the "Alternative IDSE"
option, would delay the schedule for
each IDSE requirement for two years.
Since the compliance date, for Stage 2B
would not be delayed, systems would
need to implement changes necessary
for compliance on a much shorter
schedule.
The second, the "Concurrent
Compliance Monitoring" option, would
eliminate the IDSE but require
compliance monitoring at an increased
number of sites during the first year of
compliance monitoring as a way to
identify sites with high DBP levels. This
option would reduce government
oversight and management and, as with
other rules, leave compliance
determinations and preparations to
individual systems (with guidance
available from States). In addition to
compliance monitoring at Stage 1 DBPR
compliance monitoring sites during the
first year under Stage 2B, systems would
also monitor at additional compliance
monitoring sites equal in number to the
IDSE requirement and selected using the
same criteria that systems use to select
IDSE monitoring sites. Following one
year of concurrent compliance
monitoring, the system would select
routine Stage 2B compliance monitoring
locations using a protocol similar to the
one used to recommend Stage 2B
compliance monitoring locations in the
IDSE report.
Neither alternative would extend the
compliance dates for either Stage 2A or
Stage 2B. As with the proposed IDSE,
systems would be eligible for the 40/30
certification approach if all TTHM and
HAAS compliance monitoring results in
the two years prior to the effective date
were below 0.040 mg/L and 0.030 mg/
L, respectively. States would be able to
grant very small system waivers to
systems serving <500 with a State
finding that Stage 1 DBPR compliance
monitoring locations sites are adequate
to represent both high TTHM and high
HAAS concentrations. Table V-ll
contains a comparison of the proposed
IDSE schedule and the schedules for the
alternatives.
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49607
TABLE V-11.—COMPARISON OF tDSE AND IDSE ALTERNATIVE SCHEDULES
[Dates in italics are not in today's proposed rule, but reflect EPA's recommendation and guidance]
Requirement1
Today's proposal
"Alternative IDSE"
option
"Concurrent compliance monitoring" option
IDSE start date for systems £10,000
IDSE start date for systems <10,000
IDSE report due for systems £10,000
IDSE report due for systems <10,000
State review of IDSE report complete for sys-
tems >10,000.
State review of IDSE report complete for sys-
tems <10,000.
Stage 2B compliance for systems £10,000
Stage 2B compliance for systems <10,000
0.5 years after
publication.
2.5 years after
publication.
2 years after
publication.
A years after
publication.
3 years after
publication.
4.5 years after publi-
cation.
2.5 years after
publication
4.5 years after
publication
4 years after
publication
6 years after
publication
5 years after
publication
6.5 years after publi-
cation
Requirement is for system to conduct concur-
rent compliance monitoring (generally
equal to number of samples required under
Stage 1 plus number under IDSE} during
first year of compliance monitoring. Based
on results in first year, system would iden-
tify routine compliance monitoring locations
using a procedure similar to that in IDSE
report and begin routine monitoring.
6 years after publication 2
7.5 years after publication if system is not required to- conduct Cryptosporidium monitoring; 8.5
years after publication if system required to conduct Cryptosporidium monitoring 2
1 Systems serving £10,000 also include wholesale systems and consecutive systems serving <10,000 that are part of a combined distribution
system in which at least one system serves >10,000.
2 State may grant up to two additional years for capital improvements necessary to comply.
3. Request for Comments
EPA requests comments on today's
proposed compliance schedules.
Specifically:
—Should EPA promulgate an alternative
approach to the IDSE recommended
in section V.H. that achieves the same
goal of identifying Stage 2B
compliance monitoring locations and
does not delay compliance with Stage
2B MCLs, but allows for the States to
receive primacy and be more involved
in IDSE implementation? Do either
the "Alternative IDSE" option or the
"Concurrent Compliance Monitoring"
option achieve this goal? Does one
achieve the goal better than the other?
Why? Are there either changes to
these alternatives or other alternatives
not presented that achieve this goal?
—Should EPA allow small consecutive
systems to meet Stage 2B compliance
deadlines corresponding to their size
(and later than the deadlines for their
wholesale system) provided they
complete their IDSE on the same
schedule as the wholesale system and
provided their water quality does not
affect the water quality of any other
system?
K. Public Notice Requirements
1. What is EPA Proposing?
SDWA section 1414(c) requires PWSs
to provide notice to their customers for
certain violations or in other
circumstances. EPA's public notification
rule was published on May 4, 2000 (65
FR 25982), and is codified at 40 CFR
141.201-141.210 (Subpart Q). Today's
proposal does not alter the existing
TTHM and HAA5 health effects
language that is required in most public
notices under Subpart Q. Because of the
uncertainties in the health data
discussed in section III of today's
document, EPA is not proposing to
include information about reproductive
and developmental health effects in
public notices at this time.
2. Request for Comments
EPA requests comment on the
proposed public notification
requirements, including whether
information about the possible
reproductive or fetal development
effects that may be associated with high
levels of DBPs should be provided.
L. Variances and Exemptions
States may grant variances in
accordance with sections 1415(a) and
1415(e) of the SDWA and EPA's
regulations. States may grant
exemptions in accordance with section
1416 of the SDWA and EPA's
regulations.
1. Variances
The SDWA provides for two types of
variances—general variances and small
system variances. Under section
1415(a)(l)(A) of the SDWA, a State that
has primary enforcement responsibility
(primacy), or EPA as the primacy
agency, may grant general variances
from MCLs to those public water
systems of any size that cannot comply
with the MCLs because of
characteristics of the water sources. A
variance may be issued to a system on
condition that the system install the best
technology, treatment techniques, or
other means that EPA finds available
and based upon an evaluation
satisfactory to the State that indicates
that alternative sources of water are not
reasonably available to the system. At
the time this type of variance is granted,
the State must prescribe a compliance
schedule and may require the system to
implement additional control measures.
Furthermore, before EPA or the State
may grant a general variance, it must
find that the variance will not result in
an unreasonable risk to health to the
public served by the public water
system. In this proposed rule, EPA is
specifying BATs for general variances
under section 1415(a] (see section V.F).
Section 1415(e) authorizes the
primacy agency to issue variances to
small public water systems (those
serving fewer than 10,000 people) where
the primacy agent determines (1) that
the system cannot afford to comply with
an MCL or treatment technique and (2)
that the terms of the variances will
ensure adequate protection of human
health (63 FR 1943-57; USEPA 1998d).
These variances may only be granted
where EPA has determined that there is
no affordable compliance technology
and has identified a small system
variance technology under section
1412(b)(15] for the contaminant, system
size and source water quality in
question. As discussed below, small
system variances under section 1415(e)
are not available because EPA has
determined that affordable compliance
technologies are available.
The 1996 Amendments to the SDWA
identify three categories of small public
water systems that need to be addressed:
(1) Those serving a population of 3301-
10,000; (2) those serving a population of
500-3300; and (3) those serving a
population of 25-499. The SDWA
requires EPA to make determinations of
available compliance technologies and,
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
if needed, variance technologies for
each size category. A compliance
technology is a technology that is
affordable and that achieves compliance
with the MCL and/or treatment
technique. Compliance technologies can
include point-of-entry or point-of-use
treatment units. Variance technologies
are only specified for those system size/
source water quality combinations for
which there are no listed compliance
technologies.
EPA has completed an analysis of the
affordability of DBP control
technologies for each of the three size
categories. Based on this analysis,
multiple affordable compliance
technologies were found for each of the
three system sizes (USEPA 2003i) and
therefore variance technologies were not
identified for any of the three size
categories. The analysis was consistent
with the methodology used in the
document "National-Level Affordability
Criteria Under the 1996 Amendments to
the Safe Drinking Water Act" (USEPA
1998g) and the "Variance Technology
Findings for Contaminants Regulated
Before 1996" (USEPA 1998h}.
2. What Are the Affordable Treatment
Technologies for Small Systems?
The treatment trains considered and
predicted to be used in EPA's
compliance forecast for systems serving
under 10,000 people, are listed in Table
V-12.
TABLE V-12.—TECHNOLOGIES CONSIDERED AND PREDICTED To BE USED IN COMPLIANCE TECHNOLOGY FORECAST FOR
SMALL SYSTEMS 1
SW water plants
GW water plants
Switching to chloramines as a residual disinfectant
Chlorine dioxide (Not for systems serving fewer than 100 people)
UV
Ozone (not for systems serving fewer than 100 people)
Micro-filtrationlUltra-Filtration2
GAC202
GAC20 + Advanced disinfectants
Membranes (Micro-Filtration/Ultra-Filtration + NanofHtration)
Switching to chloramines as a residual disinfectant
UV
Ozone (not for systems serving fewer than 100 people)2
GAC202
Nanofittration 2
1 Based on exhibits 6.8a and 6.8b in Economic Analysis for the proposed Stage 2 DBPR {USEPA 2003i)
2 Italicized technologies are those predicted to be used in the compliance forecast.
The household costs for these
technologies were compared against the
national-level affordability criteria to
determine the affordable treatment
technologies. The Agency's national-
level affordability criteria were
published in the August 6,1998 Federal
Register (USEPA 1998g). In this
document, EPA discussed the procedure
for affordable treatment technology
determinations for the contaminants
regulated before 1996.
The following section provides a
description of how EPA derived the
national-level affordability criteria
pertinent to this rule. First, EPA
calculated an "affordability threshold"
(i.e., the total annual household water
bill that would be considered
affordable). The total annual water bill
includes costs associated with water
treatment, water distribution, and
operation of the water system. In
developing the threshold of 2.5%
median household income, EPA
considered the percentage of median
household income spent by an average
household on comparable goods and
services and on cost comparisons with
other risk reduction activities for
drinking water such as households
purchasing bottled water or a home
treatment device. The complete
rationale for EPA's selection of 2.5% as
the affordability threshold is described
in "Variance Technology Findings for
Contaminants Regulated Before 1996"
(USEPA 1998h).
The Variance Technology Findings
document also describes the derivation
of the baselines for median household
income, annual water bills, and annual
household consumption. Data from the
Community Water System Survey
(CWSS) were used to derive the annual
water bills and annual water usage
values for each of the three small system
size categories. The data on zip codes
were used with the 1990 Census data on
median household income to develop
the median household income values
for each of the three small-system size
categories. The median household-
income values used for the affordable
technology determinations are not based
on the national median income. The
value for each size category is a national
median income for communities served
by small water systems within that
range. Table V-13 presents the baseline
values for each of the three small-system
size categories. Annual water bills are
based on 1995 estimates (USEPA 1998h)
and adjusted upward for anticipated
costs attributed to new drinking water
regulations since 1995, i.e., the IESWTR,
Stage 1 DBPR, Filter Backwash
Recycling Rule, Arsenic Rule,
LTlESWTR, Public Notification Rule,
and Consumer Confidence Rule.1
Median household income estimates are
based on estimates made in 1995
(USEPA 1998h) and adjusted upward
for inflation to represent 2000 incomes
(USEPA 2003i).
1 EPA is currently receiving input from a National
Drinking Water Advisory Council (NDWAC). This
process is expected to conclude in the fall of 2003
with a report that will be sent by the NDWAC. EPA
has also received a report from the Science
Advisory Board's Environmental Economics
Advisory Committee on its review of the national-
level affordability criteria (USEPA 2002c). One of
the charges given to both groups was to evaluate the
process used by EPA to adjust the baseline water
bills to account for costs attributable to regulations
promulgated after 1996. Because the Stage 2 DBPR
affordability analysis is being conducted before EPA
can complete a comprehensive reassessment of
affordability, today's estimate for the increase to the
average water bill to account for regulations after
1996 reflects existing Agency affordability criteria
and methodology. This estimate may change in the
future.
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49609
TABLE V-13—BASELINE VALUES FOR SMALL SYSTEMS CATEGORIES AND AVAILABLE EXPENDITURE MARGIN FOR
AFFORDABLE TECHNOLOGY DETERMINATIONS
System size category (pop. served)
•5-500
>01 3,300
i 301 10,000
Annual HH
consumption
(1000 gallons/
yr)
72
74
77
Median
HH in-
come ($)
35,148
30,893
31,559
2.5% me-
dian HH
tncome(s)
878
772
789
Current annual
water bills
($/yr)
290
230
219
Available ex-
penditure mar-
gin ($/hh/year)
588
542
570
For each size category, the threshold
alue was determined by multiplying
le median household income by 2.5
jercent. The annual household water
nils were subtracted from this value to
btain the available expenditure margin.
'rejected treatment costs were
:ompared against the available
ixpenditure margin to determine if
lere were affordable compliance
echnologies for each size category. The
available expenditure margin for the
three size categories is presented in
TableV-13.
The size categories specified in
SDWA for affordable technology
determinations are different from the
size categories typically used by EPA in
the Economic Analysis. A weighted
average procedure was used to derive
design and average flows for the 25-500
category using design and average flows
from the 25-100 and 101-500
categories. A similar approach was used
to derive design and average flows from
the 501-1000 and 1001-3300 categories
for the 501-3300 category. The Variance
Technology Findings document (USEPA
1998h) describes this procedure in more
detail. Table V-14a lists the design and
average flows for the three size
categories.
TABLE V-14A.—DESIGN AND AVERAGE DAILY FLOWS USED FOR AFFORDABLE TECHNOLOGY DETERMINATIONS
System size category (population served)
>5-500
i01 3300
! 301 10000
Design flow
(mgd)
0.058
0.50
1.8
Average flow
(mgd)
0.015
0.17
0.70
Capital and operating and
maintenance costs were derived for each
reatment technology used in the
ompliance forecast for small systems
sing the flows listed previously and
cost equations in the Technology
nd Cost Document (USEPA 2003k).
Capital costs were amortized using the
percent interest rate preferred by
Dffice of Management and Budget
OMB) for benefit-cost analyses of
overnment programs and regulations
ather than a 3 percent interest rate.
The annual system treatment cost in
ollars per year was converted into a
ate increase using the average daily
ow. The annual water consumption
alues listed in Table V-13 were
nultiplied by 1.15 to account for water
ost due to leaks. Since the water lost to
eaks is not billed, the water bills for the
ctual water used were adjusted to cover
lis lost water by increasing the
ousehold consumption. The rate
ncrease in dollars per thousand gallons
sed was multiplied by the adjusted
nnual consumption to determine the
nnual cost increase for the household
or each treatment technology.
With very few exceptions, the
ousehold costs for all predicted
ompliance technologies in Table V-12
re below the available expenditure
nargin. The only technology that was
redicted to be used in the compliance
forecast for the Stage 2 DBPR and that
costs slightly more than the available
expenditure margin is GAC20 (240 day
carbon replacement) with advanced
disinfectants for systems serving 500
people or fewer. As shown in the
Economic Analysis (USEPA 2003i), 13
systems (less than 1 percent) among
systems serving fewer than 500 people
are predicted to use GAC20 with
advanced disinfection to comply with
the proposed Stage 2 DBPR. However,
alternate affordable technologies are
available. Thus, EPA believes that
compliance by these systems will be
affordable. In some cases, the
compliance data for these systems under
the Stage 2 DBPR is the same as under
the Stage 1 DBPR (because many
systems serving fewer than 500 people
will have the same single sampling site
under both rules); these systems will
have already installed the necessary
compliance technology to comply with
the Stage l DBPR. It is also possible that
less costly technologies such as those
for which percentage use caps were set
in the decision tree may actually be
used to achieve compliance (e.g.,
chloramines, UV).
As shown in Table V-14b, the cost
model (USEPA 2003i) predicts that
households served by very small
systems will experience household cost
increases greater than the available
expenditure margins as a result of
adding advanced technology for the
Stage 2 DBPR. This prediction is
probably overestimated because small
systems have other compliance
alternatives available to them besides
adding treatment. For example, some of
these systems currently may be operated
on a part-time basis; therefore, they may
be able to modify the current
operational schedule or use excessive
capacity to avoid installing a costly
technology to comply with the Stage 2
DBPR. The system also may identify
another water source that has lower
TTHM and HAAS precursor levels.
Systems that can identify such an
alternate water source may not have to
treat that new source water as intensely
as their current source, resulting in
lower treatment costs. Systems may
elect to connect to a neighboring water
system. While connecting to another
system may not be feasible for some
remote systems, EPA estimates that
more than 22 percent of all small water
systems are located within metropolitan
regions (USEPA 2000c) where distances
between neighboring systems will not
present a prohibitive barrier. More
discussion of household cost increases
is presented in a later section (Section
VII) and the Economic Analysis (USEPA
2003i).
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Table V-14b: Annual Household Cost Increases versus Available Expenditure Margin for
Households Served by Small Systems Adding Treatment
Systems Size
(population
served)
0-500
501 - 3,300
3,301 - 10,000
Number of
Households Served
by Plants Adding
Treatment
(Percent of ail
Households Subject
42.355(3.0%)
158,044 (2.8%)
221,110(3.0%)
Mean
Annual
Household
Cost
Increase
$184.55
$47.74
$33.21
Median
Annual
Household
Cost
Increase
$189.59
$38,48
$13.30
90th
Pereentile
Annual
Household
Cost Increase
$189.59
$152.41
$98.18
95th
Pereentile
Annual
Household
Cost Increase
$409.40
$215.85
$186.72
Available
Expenditure
Margin
($/hh/yr)
$588
$542
$570
Number of
Houshdds with
Annual Cost
Increases Greater
then the Available
Expenditure Margin
1,325
0
0
Number of Plants
with Annual Cost
Increases Greater
than the Available
Expenditure
Margin
22
0
0
1Detafl may not to total add due to independent rounding. Households served by all plants will be higher than
households served by plants adding treatment because an entire system will Incur costs even if less than the total
number of plants for that system
'The affordability criteria for systems serving 25 - 500 people is $588, for systems serving 501 - 3,300 Is $542, and for
systems serving 3,301 - 10,000 Is $570
Source: Economic Analysis (USEPA 2003I) exhibit 8.4c
EPA is currently reviewing its
national-level affordability criteria, and
has solicited recommendations from
both the NDWAC and the SAB as part
of this review. If the national-level
affordability criteria are revised prior to
promulgation of tho final Stage 2 DBPR,
EPA may reevaluate the affordability of
the identified small system compliance
technologies based on the revised
criteria and may revise its determination
of whether to list any variance
technologies as a result. EPA requests
comment on the application of its
affordability criteria in this rulemaking
and on its determination that there are
affordable small system compliance
technologies for all three statutory small
system size categories.
M. Requirements for Systems To Use
Qualified Operators
EPA believes that systems that must
make treatment changes to comply with
requirements to reduce microbiological
risks and risks from disinfectants and
disinfection byproducts should be
operated by personnel who are qualified
to recognize and respond to problems.
Subpart H systems were required to be
operated by qualified operators under
the SWTR (40 CFR 141.70). The Stage 1
DBPR added requirements for all
disinfected systems to be operated by
qualified personnel who meet the
requirements specified by the State,
which may differ based on system size
and type. The rule also required that
States maintain a register of qualified
operators (40 CFR 141.130(c)j. While the
proposed Stage 2 DBPR requirements do
not supercede or modify the
requirement that disinfected systems be
operated by qualified personnel, the
Stage 2 DBPR re-emphasizes the
important role that qualified operators
play in delivering safe drinking water to
the public. States should also review
and modify, as required, their
qualification standards to take into
account new technologies (e.g.,
ultraviolet (UV) disinfection) and new
compliance requirements (including
simultaneous compliance and
consecutive system requirements).
N. System Reporting and Recordkeeping
fleguiremenfs
1. Confirmation of Applicable Existing
Requirements
Today's proposed Stage 2 DBPR,
consistent with the current system
reporting regulations under 40 CFR
141.131, requires public water systems
to report monitoring data to States
within ten days after the end of the
compliance period. In addition, systems
are required to submit the data required
in § 141.134. These data are required to
be submitted quarterly for any
monitoring conducted quarterly or more
frequently, and within ten days of the
end of the monitoring period for less
frequent monitoring.
2. Summary of Additional Reporting
Requirements
EPA proposes that two years after rule
promulgation, systems serving 10,000 or
more people (plus consecutive systems
that are part of a combined distribution
system with a system serving at least
10,000) be required to report the results
of their 1DSE to their State, unless the
State has waived this requirement for
systems serving fewer than 500. Systems
are also required to report to the State
recommended long-term (Stage 2B)
compliance monitoring sites as part of
the IDSE report. While the IDSE options
discussed in section V.J, would delay
the timing of this requirement, EPA
believes that the burden would not
change.
Beginning three years after rule
promulgation, systems must report
compliance with Stage 2A MCLs based
on LRAAs (0.120 mg/L TTHM and 0.100
mg/HAA5), as well as continue to report
compliance with 0.080 mg/L TTHM and
0.060 mg/L HAAS as RAAs. Systems
must report compliance with the Stage
2B TTHM and HAAS MCLs (0.080 mg/
L TTHM and 0.060 mg/L HAAS as
LRAAs) according to the compliance
schedules outlined in section V.J. of
today's proposal. Reporting for DBF
monitoring, as described previously,
will remain generally consistent with
current public water system reporting
requirements (§141.31 and §141.134);
systems will be required to calculate
and report each LRAA (instead of the
system's RAA) and each individual
monitoring result (as required under the
Stage 1 DBPR). Systems will also be
required to consult with the State about
each peak excursion event no later than
the next sanitary survey for the system,
as discussed in section V.E.
3. Request for Comment
EPA requests comment on all system
reporting and recordkeeping
requirements.
O. Analytical Method Requirements
1. What Is EPA Proposing Today?
The Stage 2 DBPR proposed today
does not add any new disinfectants or
disinfection byproducts to the list of
contaminants currently covered by
MRDLs or MCLs. However, additional
methods have become available since
the analytical methods in the Stage 1
DBPR were promulgated (USEPA
1998c). EPA is proposing to add to 40
CFR 141.131 one method for chlorine
dioxide and chlorite, one method for
HAAS which can also be used to
analyze for the regulated contaminant
dalapon, three methods for bromate,
chlorite, and bromide, one method for
bromate only, and one method for total
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49611
arganic carbon (TOG) and specific
ultraviolet absorbance (SUVA), One of
the methods that is currently approved
forbromate, chlorite, and bromide can
je used to determine chloride, fluoride,
nitrate, nitrite, orthophosphate, and
sulfate, so EPA is proposing to add it as
an approved method for those
contaminants in 40 CFR 141.23 and 40
^FR 143.4. EPA is also proposing to add
the HAAS method that includes dalapon
to 40 CFR 141.24 for dalapon
compliance monitoring.
Several of the methods that were
promulgated with the Stage 1 DBPR
have been included in publications that
were issued after December 1998. EPA
is proposing to approve the use of the
recently published versions of three
methods for determining free,
combined, and total chlorine residuals,
two methods for total chlorine only, one
method for free chlorine only, one
method for chlorite and chlorine
dioxide, one method for chlorine
dioxide only, one method for HAAS,
three methods for TOG and dissolved
organic carbon (DOC), and one method
for ultraviolet absorption at 254nm
(UV 254)- EPA is proposing to update the
citation for one method forbromate,
chlorite, and bromide.
EPA is also proposing to standardize
the HAAS sample holding times and the
bromate sample preservation procedure
and holding time. EPA is clarifying
which methods are approved for
magnesium hardness determinations in
40 CFR 141.131 and 40 CFR 141.135.
Analytical methods that are proposed
for approval or for which changes are
proposed in today's rule are
summarized in Table V-15 and are
described in more detail later in this
section.
TABLE V-15.—ANALYTICAL METHODS ADDRESSED IN TODAY'S PROPOSED RULE
Analyte
§141.23
§141.24
§141.131— Disinfectants
(total)
free)
§141.131— Disinfection Byproducts
HAA5
§141.131 — Other parameters
TOC/DOC
jV,. How Was This Proposal Developed?
EPA evaluated the performance of the
lew methods for their applicability to
compliance monitoring. The primary
jurpose of this evaluation was to
letermine if the new methods provide
data of comparable or better quality than
the methods that are currently
approved. Methods currently approved
for DBFs were also examined to
determine applicability to other
regulated contaminants.
EPA reviewed the new publications of
methods from consensus organizations
such as Standard Methods and
American Society for Testing and
Materials (ASTM). As a result, EPA
identified one new method from ASTM
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which is suitable for compliance
monitoring. EPA also determined that
the newer editions of Standard Methods
did not change the individual methods
approved under the Stage 1 DBPR.
3. Which New Methods Are Proposed
for Approval?
a. EPA Method 327.0 for chlorine
dioxide and chlorite. EPA is proposing
to add a new method for the
measurement of chlorine dioxide
residuals and daily chlorite
concentrations. EPA Method 327.0
(USEPA 2003q) is an enzymatic/
spectrophotometric method in which a
total chlorine dioxide plus chlorite
concentration is determined in an
unsparged sample and the chlorite
concentration is determined in a
sparged sample. The chlorine dioxide
concentration is then calculated by
subtracting the chlorite concentration
from the total.
The pH of the samples (sparged and
unsparged) and blank are adjusted to 6.0
with a citric acid/glycine buffer. The
chromophore Lissamine Green B (LGB)
and the enzyme horseradish peroxidase
are added. The enzyme reacts with the
chlorite in the sample to form chlorine
dioxide which then reacts with the
chromophore LGB to reduce the
absorbance at 633nm of the sample. The
absorbance of the samples and blank are
determined spectrophotometrically. The
difference in absorbance between the
samples and the blank is proportional to
the chlorite and total chlorine dioxide/
chlorite concentrations in the samples.
EPA Method 327.0 offers advantages
over the currently approved methods in
that it is not subject to positive
interferences from other chlorine
species and it is easier to use.
The single laboratory detection limits
presented in the method are 0,08-0.11
mg/L for chlorite and 0.04-0.16 mg/L
for chlorine dioxide. The detection
limits are based on the analyses of sets
of seven replicates of reagent water that
were fortified with low concentrations
of chlorite with and without the
presence of chlorine dioxide and low
concentrations of chlorine dioxide with
and without the presence of chlorite.
The standard deviation of the mean
concentration for each set of samples
was calculated and multiplied by the
student's t-value at 99% confidence and
n-1 degrees of freedom (3.143 for 7
replicates) to determine the detection
limit. The accuracy reported in the
method for laboratory fortified blanks at
concentrations of 0.2-1.0 mg/L is 103-
118 % for chlorite and 102-124 % for
chlorine dioxide with relative standard
deviations between 2.9 and 16 %.
Replicate analyses of drinking water
samples from surface and ground water
sources fortified at concentrations of
approximately 1 and 2 mg/L chlorite
and chlorine dioxide showed average
recoveries of 91-110 % with relative
standard deviations of 1-9 %.
EPA is proposing to approve EPA
Method 327.0 as an additional method
for monitoring chlorine dioxide and for
making the daily determination of
chlorite at the entry point to the
distribution system. It will provide
water systems with additional flexibility
in monitoring the application of
chlorine dioxide. EPA believes that
many water plant operators will prefer
the new method over the currently
approved methods due to its ease of use.
b. EPA Method 552.3 forHAA5 and
dalapon. EPA is proposing to add a new
method (EPA Method 552.3) for HAAS
that provides comparable sensitivity,
accuracy, and precision to the
previously approved methods. EPA
Method 552.3 (USEPA 2003p) has the
added benefit of allowing laboratories to
more easily measure four additional
haloacetic acids (bromochloroacetic
acid, bromodichloroacetic acid,
chlorodibromoacetic acid, and
tribromoacetic acid) at the same time
the HAA5 compounds are being
measured, without compromising the
quality of data for the HAA5
compounds. Of the currently approved
methods for HAA5, only EPA Method
552.2 (USEPA 1995) provides method
performance data for all of these
additional compounds, but the reaction
conditions must be carefully controlled.
EPA believes that analyses for these
additional HAAs can be accomplished
more easily without compromising the
quality of data for the HAAS
compounds by using EPA Method
552.3.
EPA Method 552.3 for HAAS, other
haloacetic acids, and the regulated
contaminant dalapon allows two
extraction options. The first option
involves an acidic extraction with
methyl tertiary butyl ether (MTBE)
which is the same solvent used in the
currently approved HAA5 methods. The
analytes (HAAS, other HAAs, and
dalapon) are then converted to their
methyl esters by the addition of acidic
methanol to the extract followed by
heating. The amount of acidic methanol
that is added to the extract is increased
in the new method resulting in
increased methylation efficiency for
some of the analytes. The increased
methylation efficiency is significant for
the additional HAAs and thus provides
greater sensitivity, precision, and
accuracy for them when compared to
EPA Method 552.2. The acidic extract is
neutralized with a saturated solution of
sodium bicarbonate and the target
analytes are identified and measured by
gas chromatography using electron
capture detection (GC/EGD).
The second option in the new EPA
Method 552.3 involves an acidic
extraction with tertiary amyl methyl
ether (TAME). The HAAs are then'
converted to their methyl esters by the
addition of acidic methanol to the
extract followed by heating. The use of
TAME instead of MTBE as the
extraction solvent allows the use of a
higher temperature during the
methylation process. This increases the
methylation efficiency and thus
provides significant increases in
sensitivity, precision, and accuracy for
the additional HAAs. The acidic extract
is neutralized with a saturated solution
of sodium bicarbonate and the target
analytes are identified and measured by
gas chromatography using electron
capture detection (GC/ECD).
The performance of EPA Method
552.3 is comparable to the currently
approved methods for determining the
HAAS analytes. A comparison of the
performance of EPA Method 552.3 to
the currently approved HAAS methods
is shown in Table V-16. The data are
taken from the individual methods, so
the precision, accuracy, and detection
data were not generated using the same
samples or by the same laboratory.
TABLE V-16.—PERFORMANCE OF HALOACETIC ACID METHODS
QC Parameter
Precision (Max %RSD in fortified drinking water samples) 1
EPA 552.1
EPA 552.2
EPA 552.3 (MTBE option)
EPA 552.3 (TAME option)
SM6251 B
MCAA
DCAA
TCAA
28
MBAA
11
6
4
4
8
DBAA
7
5
5
5
7
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49613
TABLE V-16.—PERFORMANCE OF HALOACETIC ACID METHODS—Continued
QC Parameter
Accuracy (Range of % Recoveries in fortified drinking water samples) 2
EPA 552.1
EPA 552.2
EPA 552.3 (MTBE option)
EPA 552.3 (TAME option)
3M 6251 B
Detection Limit (ng/L) 3
EPA 552.1
EPA 552.2
EPA 552.3 (MTBE option)
EPA 552.3 (TAME option)
5M6251 B
MCAA
76-100
84-97
98-126
97-131
99-103
0.21
027
0.17
0.20
0.08
DCAA
75-126
96-105
96-103
97-107
96-103
045
024
0.02
0.08
005
TCAA
56-106
62-82
89-100
89-103
100-103
007
008
002
002
005
MBAA
86-97
86-100
99-113
99
97 101
024
003
0 13
009
DBAA
1 The highest relative standard deviation (%RSD) for replicate analyses of fortified drinking water samples as shown in each method.
2 The range of recoveries reported for replicate analyses of fortified drinking water samples as shown in each method.
3 The detection limit as determined by analyzing seven or more replicates of reagent water that is fortified with low concentrations of the
laloacetic acids. The standard deviation of the mean concentration for each analyte is calculated and multiplied by the student's t-value at 99%
;onfidence and n-1 degrees of freedom (3.143 for 7 replicates).
Two of the currently approved HAA5
nethods (EPA Methods 552.1 (USEPA
992) and 552.2 (USEPA 1995)) are also
pproved for analyses of water samples
'or the regulated contaminant dalapon,
a synthetic organic chemical. The new
HAA5 method can also be used to
determine dalapon in drinking water.
As shown in Table V-17, both solvent
options in EPA Method 552.3 provide
comparable or better method
performance than the approved
methods.
TABLE V-17.—PERFORMANCE OF DALAPON METHODS
Decision1 (% RSD)
EPA 552 1
14
88-102
032
11
86-100
0 12
EPAE
MTBE
2
002
>52.3
TAME
4
1 The highest relative standard deviation (%RSD) for replicate analyses of fortified drinking water samples as shown in each method.
2 The range of recoveries reported for replicate analyses of fortified drinking water samples as shown in each method.
3 The detection limit as determined by analyzing seven or more replicates of reagent water that is fortified with low concentrations of dalapon.
The standard deviation of the mean dalapon concentration is calculated and multiplied by the student's t-va!ue at 99% confidence and n-1 de-
rees of freedom (3.143 for 7 replicates).
EPA is proposing to approve EPA
Method 552.3 for dalapon
§ 141.24(e)(l)) in addition to HAA5
ven though dalapon is not a
ontaminant that is addressed in this
roposed rule. EPA believes that
xtending approval to all the regulated
ontaminants covered by the method
rovides more flexibility to laboratories.
allows the laboratories the option of
educing the number of methods that
ley need to keep in operation for their
lients, because the new method can be
sed for dalapon and HAAS compliance
nonitoring samples and for determining
le additional HAAs for non-regulatory
urposes. EPA recognizes that
aboratories will probably not be
etermining dalapon concentrations for
ompliance purposes in the same
amples as used for HAA5 compliance
nonitoring. However, EPA believes
[lowing the same method to be used
ven if the samples are not the same is
nore cost effective for laboratories,
ecause switching between methods
esults in increased analyst and
instrument time. EPA is not proposing
to withdraw the other dalapon methods,
because that would reduce flexibility for
the laboratories and place an
unnecessary burden on laboratories that
do not need to use EPA Method 552.3.
c. ASTMD 6581-00 for bromate,
chlorite, and bromide. ASTM Method D
6581-00 (ASTM 2002) for the
determination of bromate, chlorite, and
bromide was adopted by ASTM in 2000.
This method uses the same procedures
as EPA Method 300.1 (USEPA 20001)
(the method promulgated in the Stage 1
DBPR) and thus is considered
equivalent to the approved method
(Hautman et al 2001). The ASTM
method includes interlaboratory study
data that were not available when EPA
Method 300.1 was published. The study
data demonstrate good precision and
low bias for all analytes.
Under section 12(d) of the National
Technology Transfer and Advancement
Act, the Agency is directed to consider
whether to use voluntary consensus
standards in its regulatory activities.
ASTM Method D 6581-00 is an
acceptable consensus standard and it is
published in the 2001, 2002, and 2003
editions of The ASTM Annual Book of
Standards. EPA is proposing to approve
ASTM Method D 6581-00 in order to
provide additional flexibility to
laboratories. Any edition containing the
cited version may be used.
d. EPA Method 317.0 revision 2 for
bromate, chlorite, and bromide. EPA
Method 317.0 Revision 2 (USEPA
200ld) is an extension of the currently
approved EPA Method 300.1 for
bromate, chlorite, and bromide. It uses
the EPA Method 300.1 technology, but
it adds a postcolumn reactor that
provides a more sensitive and specific
analysis for bromate than is obtained
using EPA Method 300.1. As with EPA
Method 300.1, the anions are separated
by ion chromatography and detected
using a conductivity detector. (Bromate,
chlorite, and bromide concentrations
determined by the conductivity detector
are equivalent to those measured using
EPA Method 300.1.) After the sample
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passes through the conductivity
detector, it enters a postcolumn reactor
chamber in which o-dianisidine
dihydrochloride {ODA} is added to the
sample. This compound forms a
chromophore with the bromate that is
present in the sample and the
chromophore concentration is
determined using a ultra violet/visible
(UV/Vis) absorbance detector. There are
several advantages of this method:
(1) Very few ions react with ODA to
form compounds that are detected by
the UV/Vis detector. This makes the
method less susceptible to interferences
for bromate.
(2) The UV/Vis detector is very
sensitive to the chromophore, so lower
concentrations of bromate can be
detected and quantitated. (Bromate
concentrations can be reliably
quantitated as low as 1 ug/L using this
detector versus 5 Ug/L for EPA Method
300.1.)
(3) Since the front part of the analysis
is the same as EPA Method 300.1,
bromate, chlorite, and bromide can be
determined in the same analysis.
The first version of this method, EPA
Method 317.0 has been evaluated in a
multiple laboratory study (Wagner et al.
2001; Hautman et al. 2001). The results
from the study indicate high precision
and very low bias in data generated
using this method. The interlaboratory
precision for bromate, chlorite, and
bromide using the conductivity detector
and bromate using the UV/Vis detector
are 12%, 4.2%, 6.9%, and 9.6% relative
standard deviation (RSD), respectively.
The interlaboratory bias for bromate,
chlorite, and bromide using the
conductivity detector and bromate using
the UV/Vis detector are 0.35%,
-0.98%, -0.87%, and 4.8%,
respectively. The average detection
levels for bromate, chlorite, and
bromide using the conductivity detector
and bromate using the UV/Vis detector
are 2.2,1.6, 2.8, and 0.24 Ug/L,
respectively.
Subsequent to the interlaboratory
study of EPA Method 317.0, a problem
with ODA was discovered. The purity of
the reagent can vary from lot to lot and
this affects the performance of the
method. EPA has evaluated the method
performance using ODA obtained from
several commercial sources and from
different lots from the same supplier.
Based on that new information, EPA
revised Method 317.0 to document how
to detect and correct problems that can
result from a contaminated ODA supply.
The revised method is designated EPA
Method 317.0 Revision 2.0 and this is
the version that is being proposed today.
The performance of the revised method
is identical to the original version.
EPA believes EPA Method 317.0
Revision 2.0 should be approved as an
additional method for bromate, chlorite,
and bromide compliance monitoring.
EPA anticipates that water systems will
prefer to have their bromate samples
analyzed by this new method, because
it provides higher quality data than the
currently approved method when
bromate concentrations are below the
MCL of 0.010 mg/L (10 ug/L). Only a
few laboratories are currently
performing analyses using the
postcolumn reactor technology included
in the method, but the number is
increasing as more laboratories become
aware of the advantages.
e. EPA Method 326,0 for bromate,
chlorite, and bromide. EPA Method
326.0 (USEPA 2002a) is based on the
procedure reported by Salhi and von
Gunten (1999) and uses an approach
that is similar to EPA Method 317.0
Revision 2.0. The method involves the
separation of the anions (bromate,
chlorite, and bromide) following the
scheme outlined in EPA Methods 300.1
and 317.0 Revision 2.0. (Bromate,
chlorite, and bromide data from the
conductivity detector are equivalent to
data generated using EPA Method
300.1.) The eluent stream exiting the
conductivity detector is mixed with a
postcolumn reagent consisting of an
acidic solution of potassium iodide with
a catalytic concentration of
molybdenum (VI). Bromate reacts with
the iodide to form triiodide which is
measured by its UV absorption at 352
nm.
EPA Method 326.0 has similar
accuracy, precision, and sensitivity for
bromate compared to EPA Method 317.0
Revision 2.0. Thirty drinking water
samples fortified with 1-7 M-g bromate/
L were analyzed using both methods.
Accuracy, expressed as % recovery,
ranged from 78.0 to 129% for both
methods and precision, expressed as %
RSD ranged from 3.7 to 13.5% (Wagner
et al. 2002). The detection limit of EPA
Method 326.0 is 0.17 ug/L as
determined by analyzing seven or more
replicates of reagent water that is
fortified with low concentrations of
bromate. The standard deviation of the
mean bromate concentration is
calculated and multiplied by the
student's t-value at 99% confidence and
n-1 degrees of freedom (3.143 for 7
replicates).
EPA is proposing EPA Method 326.0
as an additional method for bromate,
chlorite, and bromide compliance
monitoring. It provides higher quality
bromate data than the currently
approved EPA Method 300.1 when
bromate concentrations are below 10 ug/
L. EPA anticipates the number of
laboratories using this method will
increase as utilities become aware of the
method's sensitivity and begin to
request it be used for their samples.
f. EPA Method 321.8 for bromate. EPA
is proposing to add EPA Method 321.8
(USEPA 2000d) specifically for bromate
compliance monitoring. It involves an
ion chromatograph coupled to an
inductively coupled plasma mass
spectrometer (IC/ICP-MS). The ion
chromatograph separates bromate from
other ions present in the sample and
then bromate is detected and
quantitated by the ICP-MS. Mass 79 is
used for quantitation while mass 81
provides isotope ratio information that
can be used to screen for potential
polyatomic interferences. The advantage
of this method is that it is very specific
and sensitive to bromate. The single
laboratory detection limit presented in
the method is 0.3 ug/L. The average
accuracy reported in the method for
laboratory fortified blanks is 99.8%
recovery with a three sigma control
limit of 10.2%. Average accuracy and
precision in fortified drinking water
samples are reported as 97.8% recovery
and 2.9% relative standard deviation,
respectively.
During the Information Collection
Rule, thirty-three samples were
analyzed by this method in addition to
the selective anion concentration (SAC)
method used by EPA for the low-level
bromate analyses. EPA Method 321.8
provided comparable data to that
generated by the SAC method (Fair
2002).
EPA Method 321.8 has undergone
second laboratory validation (Day et al.
2001) and the results indicate the
method can be successfully performed
in non-EPA laboratories. The calculated
detection limit determined by the
second laboratory is 0.4 ug/L. The
average accuracy achieved for laboratory
fortified blanks at 5 ug/L js 93%
recovery with a relative standard
deviation of 8.9%. Average accuracy
and precision in fortified drinking water
samples are reported as 101% recovery
and 9% relative standard deviation,
respectively.
The IC/ICP-MS instrumentation used
in EPA Method 321.8 is a new
technology in the drinking water
laboratory community. Even though the
technology is not yet widely used, EPA
believes that approving this new
method will provide laboratories with
the flexibility to adopt the new
technology if they have additional
applications for it. The instrumentation
is especially promising in the area of
trace metal speciation. Laboratories that
are performing that type of analysis
would find it very useful to also be able
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49615
to perform bromate compliance
monitoring analyses by EPA Method
321.8. EPA believes that advances in
analytical technology should be
encouraged when they provide
additional options for obtaining
accurate and precise data for
compliance monitoring. Approval of
this method would not require
laboratories to adopt the new
technology; it strictly offers the choice
for laboratories that would like to use
the latest technology.
EPA is proposing to add sample
collection and holding time requirement
to EPA Method 321.8. The current
method does not address the potential
for changes in bromate concentrations
after the sample is collected as a result
of reactions with hypobromous acid/
hypobromite ion. Hypobromous acid/
hypobromite ion are intermediates
formed as byproducts of the reaction of
either ozone or hypochlorous acid/
hypochlorite ion with bromide ion. If
not removed from the sample matrix,
further reactions may form bromate ion.
The reactions can be prevented by
adding 50 mg of ethylenediamine
(EDA)/L of sample. This is the
preservation technique specified in the
other methods both approved and
proposed for bromate compliance
analyses. The fortified drinking water
samples analyzed in the second ,
laboratory validation study of EPA
Method 321.8 (Day et al 2001) and the
Information Collection Rule samples
that were analyzed using the SAC
method and EPA Method 321.8 were
preserved with EDA, thus
demonstrating that EDA can be used in
samples analyzed by IC/ICP-MS. EPA
believes that adding this sample
preservation requirement to EPA
Method 321.8 will help ensure sample
integrity. It will also simplify the
sampling protocols that water systems
must follow, because al! sampling for
bromate, regardless of the method
employed to analyze the sample, will
require the same sample preservation
technique.
EPA Method 321.8 does not include
information concerning how long a
sample may be stored prior to analysis.
EPA is proposing to specify a maximum
of 28 days for the sample holding time.
This would make the method consistent
with the other bromate methods
proposed today and the method that is
currently approved.
g. EPA 415.3 for TOC and SUVA
(DOC and WZSA). Today's rule proposes
to add EPA Method 415.3 (USEPA
2003r) as an approved method for TOC
and SUVA. The Stage 1 DBPR included
three Standard Methods for TOC and
one method for UV*254. Additional
quality control (QC) requirements were
included for these measurements,
because the methods did not contain the
necessary criteria. The rule included
instructions for calculating SUVA based
on UV254 and DOC analyses. The new
EPA Method 415.3 includes the
additional QC necessary to achieve
reliable determinations for TOC, DOC,
and UV254. It describes a procedure for
removing inorganic carbon from the
sample prior to the organic carbon
analysis. The method uses the same
technologies as already approved. The
advantage of this new method is that it
documents the precision and accuracy
that can be expected when proper QC
procedures are implemented and it
places all the necessary information for
SUVA in one place.
EPA Method 415.3 provides
sensitivity, precision and accuracy data
for TOC and DOC measured using five
different technologies:
(1) Catalyzed 680°C combustion
oxidation of organic carbon to carbon
dioxide (CO2) followed by
nondispersive infrared detection
(NDIR).
(2) High temperature (700 to 1100°C)
combustion oxidation followed by
NDIR.
(3) Elevated temperature (95-100°C)
catalyzed persulfate digestion of organic
carbon to CO2 followed by NDIR.
(4) UV catalyzed persulfate digestion
followed by NDIR.
(5) UV catalyzed persulfate digestion
followed by membrane permeation into
a conductivity detector.
These technologies are included in the
currently approved Standard Methods
5310 B and 5310 C (APHA, 1996). The
new method indicates these
technologies can provide detection
limits between 0.02 mg/L and 0.12 mg/
L. Accuracy and precision data from
analyses of fortified reagent water and
natural waters indicate the technologies
can produce acceptable data for
determining compliance with the
treatment technique for control of
disinfection byproduct precursors
specified in § 141.135. Seven natural
waters were fortified with organic
carbon from potassium hydrogen
phthalate and analyzed by each of the
five technologies. The average
recoveries ranged from 97% to 103% for
TOC and 98% to 106% for DOC.
The method presents data from the
analyses of seven different waters and
demonstrates that comparable analytical
results are obtained regardless of the
technology used as long as all inorganic
carbon is removed from the sample
prior to the analysis. The samples
ranged in concentration from 0.4 to 3.6
mg/L and the relative standard
deviations across the analyses ranged
from 35% RSD (for the lowest
concentration sample) to <13% RSD for
the remainder of the samples.
EPA Method 415.3 includes a
procedure to ensure that inorganic
carbon does not interfere with the
organic carbon analyses. Since this is
critical to obtaining accurate organic
carbon determinations, EPA is
proposing to add a requirement at
§§ 141.131(d)(3) and (4)(i) to remove
inorganic carbon prior to performing
TOC or DOC analyses. Laboratories will
have the option of using the procedure
described in EPA Method 415.3 or
verifying that the process used by their
TOC instrument adequately removes the
inorganic carbon prior to the organic
carbon measurement. Determination of
organic carbon by subtracting the
inorganic carbon from the total carbon
is not acceptable for compliance
purposes, because the percentage of
inorganic carbon is usually large in
relation to the organic carbon of the
sample and the subtraction process
introduces a large potential for error.
The manufacturer of one of the
instruments that was used during the
development of EPA Method 415.3
recommends that hydrochloric acid be
used to acidify TOC and DOC samples
prior to analysis. EPA confirmed that
use of this acid is critical for proper
operation of the instrument. However,
use of hydrochloric acid is in conflict
with the current regulation at
§§ 141.131(d)(3) and (4)(i) which specify
phosphoric or sulfuric acid. The type of
acid used to preserve samples and to
treat the samples to remove inorganic
carbon prior to the organic carbon
analysis should be based on the
analytical method, or the instrument
manufacturer's specification. Therefore,
EPA is proposing to remove the
specification of acid type from
§§141.131(d)(3)and(4)(i).
EPA Method 415.3 specifies that TOC
samples be acid preserved at the time of
collection in order to prevent microbial
degradation of the organic carbon. This
is consistent with the sampling
instructions in the currently approved
methods (Standard Methods 5310 B,
5310 C, and 5310 D). EPA proposes to
amend § 141.131(d)(3) by removing the
phrase "not to exceed 24 hours" in the
description of when samples must be
preserved, so that the rule is consistent
with the method specifications.
Analyses for both DOC and UV254 are-
required for a SUVA determination. The
DOC measurement is identical to the
TOC measurement after the sample is
filtered through a 0.45 urn pore size
filter. The filtration step must be
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
performed using a prewashed filter in
order to eliminate positive interferences
from material that can leach from
improperly cleaned filters. EPA Method
415.3 contains a description of how to
properly rinse the filters and how to
verify that the filter blank is acceptable.
The method demonstrates that it is
feasible to have a filter blank with a
DOC concentration <0.2 mg/L. The
method also provides performance data
for DOC.
The Uv*254 analysis that is part of the
SUVA determination is also described
in EPA Method 415.3. As with the DOC
measurement, the UV254 analysis is
performed on a sample that has been
filtered through a prewashed 0.45 um
pore size filter. In addition to verifying
that the filter blank is low enough, the
method also includes a
spectrophotometer check procedure to
ensure that the spectrophotometer is
operating properly.
4, What Additional Regulated
Contaminants Can Be Monitored by
Extending Approval of EPA Method
300.1?
In addition to bromate, chlorite, and
bromide, EPA Method 300,1 (USEPA
20001) can also be used to determine
chloride, fluoride, nitrate, nitrite,
orthophosphate, and sutfate in drinking
water. A comparison of the performance
of EPA Method 300.1 to the currently
approved EPA Method 300.0 (USEPA
1993} is shown in Table V-18 and
demonstrates that EPA Method 300.1
provides comparable or better precision,
accuracy, and sensitivity for these
contaminants based on the single
laboratory data presented in each
method.
TABLE V-18.—COMPARISON OF EPA METHODS 300.0 AND 300.1
QC parameter
Chloride
Fluoride
Nitrate
Nitrite
Phosphate-
P
Sulfate
Precision (Max % RSO in fortified water samples)'
EPA 300.0
EPA 300.1
5.7
0.22
16
0.85
4.8
0.41
3.6
0.77
3.5
4.7
71
039
Accuracy (Range of % Recoveries in fortified water samples)2
EPA 300.0
EPA 300.1
86-114
93-98
73-95
80-89
93-104
88-96
92-121
72-87
95-99
61-92
95-112
89
Detection Limit (mg/L)3
EPA 300.0
EPA 300.1
0.02
0004
0.01
0009
0.002
0008
0.004
0001
0003
0 019
0 02
0019
1 The highest relative standard deviation (%RSD) reported in the method for replicate analyses of fortified water samples in a single laboratory.
2The range of recoveries reported for replicate analyses of fortified water samples in a single laboratory as shown in the method.
3The detection limit as determined by analyzing seven or more replicates of reagent water that is fortified with low concentrations of the
anions. The standard deviation of the mean concentration for each analyte is calculated and multiplied by the student's t-value at 99% con-
fidence and n-1 degrees of freedom (3.143 for 7 replicates).
EPA is proposing to extend approval
of EPA Method 300.1 for fluoride,
nitrate, nitrite, and orthophosphate
(§ 141.23{k)(l)) and for chloride and
sulfate (§ 143.4(b)) even though these
contaminants are not addressed in
today's proposed rule. As discussed
before for dalapon, EPA believes that
extending approval to all the regulated
contaminants covered in a method
provides greater flexibility to
laboratories and allows them to reduce
analytical costs. EPA recognizes that
laboratories will probably not be
determining concentrations of these
non-DBP anions for compliance
purposes in the same samples as used
for chlorite or bromate compliance
monitoring. However, EPA believes
allowing the same method to be used
even if the samples are not the same is
more cost effective for laboratories. EPA
is not proposing to withdraw any
methods for the non-DBP anions,
because that would place an
unnecessary burden on laboratories that
do not need to use EPA Method 300.1.
5. Which Methods in the 20th Edition
and 2003 On-Line Version of Standard
Methods Are Proposed for Approval?
The Stage 1 DBPR approved eight
methods (4500-Cl D, 4500-C1 F, 4500-
Cl G, 4500-Cl E, 4500-Cl I, 4500-Cl H,
4500-C1O2 D, and 4500-C1O2 E) for
determining disinfection residuals from
the 19th edition of Standard Methods
(APHA, 1995). Standard Methods 6251
B and 4500-CIO2 E in the 19th edition
of Standard Methods (APHA, 1995)
were approved for HAAS and daily
chlorite analyses, respectively. Three
TOG methods (5310 B, 5310 C, and 5310
D) from the Supplement to the 19th
edition of Standard Methods (APHA,
1996) and one UV254 method (5910 B)
from the 19th edition of Standard
Methods (APHA, 1995) were also
approved in the Stage 1 DBPR.
.These thirteen methods are
unchanged in the 20th edition of
Standard Methods (APHA, 1998), so
EPA proposes to cite the 20th edition for
these analyses in addition to the 19th
editions.
The On-Line Version of Standard
Methods is an effort to provide the
consensus methods to the public prior
to the release of the next full
publication. Standard Methods is
making sections of the next version
available for purchase in both electronic
or printed format. EPA has reviewed the
applicable sections and determined that
ten of the methods are identical to the
currently approved versions from the
19th editions. Section 4500-Cl contains
the methods for determining chlorine
residuals and it includes the 4500-Cl D,
4500-CI F, 4500-Cl G, 4500-Cl E, 4500-
Cl I, and 4500-Cl H. Section 4500-C1O2
contains the methods for determining
chlorine dioxide residuals and chlorite
and it includes method 4500-C1O2 E.
Section 5310 contains the methods for
determining TOG and it includes
methods 5310 B, 5310 C, and 5310 D.
Because the ten listed methods in these
sections are unchanged from the
versions that were published in the 19th
editions, EPA is proposing to cite the
On-Line Version for these analyses in
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49617
iddition to the currently approved 19th
jditions and the proposed 20th edition.
Section 6251 includes method 6251 B
or HAAS. The method has been
ipdated for the On-Line Version to
nclude precision and accuracy data
rom the Information Collection Rule
ind the sample holding time has been
ixtended from 9 days to 14 days. The
idditional quality control data does not
echnically change the method from the
jreviously approved version in the 19th
)dition; it simply demonstrates the
)erformance that can be expected when
he method is used. The change in
;ample holding time is consistent with
SPA's proposal to standardize the HAA5
;ample holding time at 14 days (See
liscussion in section V.O.7). Thus EPA
s proposing to cite the On-Line Version
or this analysis in addition to the
;urrently approved 19th edition and the
>roposed 20th edition.
Section 5910 includes method 5910 B
or determining UVssi. The method has
ieen updated for the On—Line Version
o include precision data from the
nformation Collection Rule. Because
he additional quality control data does
lot technically change the method from
he previously approved version in the
9th edition, EPA is proposing to cite
he On-Line Version for this analysis in
iddition to the currently approved 19th
idition and the proposed 20th edition.
The On-Line Version of Standard
vfethods will not include method 4500-
j\O2 D, so it is not being proposed with
he other twelve methods cited in the
)n-Line Version.
EPA is proposing to add a citation to
he 20th edition and the On-Line
Version of Standard Methods for
hirteen and twelve methods,
espectively. EPA believes these should
IB cited in addition to the 19th editions
n order to allow flexibility for the water
ystems performing the analyses.
Vithdrawal of the older editions would
equire all systems to purchase one of
he newer editions, which could impose
n unnecessary burden on systems that
ise the reference for only a few
nethods.
i. What Is the Updated Citation for EPA
Method 300.1?
EPA Method 300.1 (USEPA 20001) for
iromate, chlorite and bromide is now
ncluded in an EPA methods manual
bat was published August 2000. The
aanual titled "Methods for the
Jetermination of Organic and Inorganic
Compounds in Drinking Water" is a
ompilation of methods developed by
PA for drinking water analyses. EPA
Method 300.1 was previously only
vailable as an individual method. EPA
iroposes to update the bromate,
chlorite, and bromide citation for this
method to the August 2000 methods
manual in today's rule so that the users
are directed to the correct source of the
method.
7. How Is the HAA5 Sample Holding
Time Being Standardized?
The analytical methods approved for
HAAS compliance monitoring (EPA
552.1, EPA 552.2, and Standard Method
6251 B) all specify the use of
ammonium chloride to eliminate the
free chlorine residual in samples and
they require samples be iced/
refrigerated after collection. Even
though the sampling parameters agree in
the three methods, the methods specify
different sample holding times (time
between sample collection and
extraction). EPA Methods 552.1 (USEPA
1992) and 552.2 (USEPA 1995) allow at
least 14 days while Standard Method
6251 B (APHA 1995 and 1998) specifies
that samples must be extracted within
nine days of sample collection. The
holding time for the Standard Method is
based on data which indicated an
increase in DCAA concentration to
slightly greater than 120% of the initial
concentration after the sample was
stored for 14 days (Krasner et aJ. 1989).
All other HAA5 compounds were well
within the 80-120% criteria set by the
researchers. The decision was made to
use a conservative approach to be sure
that the concentrations of all HAAs
were stable, and nine days was the
closest data point to the 14 day-data
point in question. Subsequent to
Krasner's study, EPA conducted
additional sample holding time studies
as part of the EPA methods
development process. EPA has
published data to support the 14-day
sample holding time for the HAAS
compounds (Pawlecki-Vonderheide et
al. 1997; USEPA 2003p). Since there is
no technical reason for the holding
times to be different between the HAAS
methods addressed in this rule, EPA
proposes to allow a 14-day sample
holding time for samples being analyzed
by Standard Method 6251 B. This would
provide consistency across methods and
it would simplify sampling
considerations for water systems. EPA is
only proposing to standardize the
holding time allowed for the samples.
Due to differences in the sample
preparation (i.e., extraction) procedures
in the various methods, the extract
holding times cannot be standardized.
Laboratories must follow the individual
method requirements when determining
storage conditions and holding times for
the extracts.
EPA Method 552.1 specifies a 28-day
holding time for HAA samples. This
was based on studies conducted on
fortified reagent water samples rather
than drinking water samples. Because
HAAs have been shown to biodegrade
in some distribution systems (Williams
et al. 1995), EPA believes that some
samples may not be stable for 28 days.
Today's rule proposes reducing the
holding time to 14 days when EPA
Method 552.1 is used in order to better
ensure sample stability. During the
Information Collection Rule, EPA only
allowed the 14-day sample holding
time for all HAA samples (regardless of
the method used to analyze the
samples), so laboratories and water
systems have demonstrated their
capability to implement this method
change.
EPA believes that by standardizing
the sample holding times allowed in the
various HAAS methods, the burden for
laboratories and water systems will be
reduced. Sampling considerations will
be simplified, because all HAAS
samples will be collected and stored the
same way.
8. How Is EPA Clarifying Which
Methods Are Approved for Magnesium
Determinations?
The Stage 1 DBPR allows systems
practicing enhanced softening that
cannot achieve the specified level of
TOC removal, to meet instead one of
several alternative performance criteria,
including the removal of 10 mg/L
magnesium hardness (as CaCOS) from
the source water. Analytical methods for
measuring magnesium hardness were
not included in the rule, but they were
later promulgated in a Methods Update
Rule (USEPA 1999b). The December
1999 Methods Rule cited the
magnesium methods at § 141.23(k)(l),
but it did not identify that these
methods were to be used to demonstrate
compliance with the alternative
performance criteria specified in
§ 141.135(a)(3)(ii). EPA is proposing to
clarify this today by referencing the
approved magnesium methods at
§ 141.131(d)(6) and § 141.135(a)(3)(ii).
9. Which Methods Can Be Used To
Demonstrate Eligibility for Reduced
Bromate Monitoring?
Today's rule proposes to change the
monitoring requirements for
demonstrating eligibility to reduce
bromate monitoring from monthly to
quarterly. The Stage 1 DBPR allows the
monitoring to be reduced if the system
demonstrates that the average source
water bromide concentration is less than
0.05 mg/L based upon monthly bromide
measurements for one year. Today's rule
proposes to change that requirement to
a demonstration that the finished water
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
bromate concentration is <0.0025 mg/L
as a running annual average. If this
change is implemented, there will no
longer be a need for bromide
compliance monitoring methods. EPA is
proposing additional bromide methods
today in order to provide flexibility to
the laboratories and water systems in
the interim period before the Stage 2
DBPR compliance monitoring
requirements becomes effective.
In order to qualify for reduced
bromate monitoring, EPA is proposing
that the samples must be analyzed for
bromate using either EPA Method 317.0
Revision 2.0 (UV/Vis detector), EPA
Method 326.0 (UV/Vis detector), or EPA
Method 321.8. These three methods can
provide quantitative data for bromate
concentrations as low as 0.001 mg/L,
thus ensuring that a bromate running
annual average of <0.0025 mg/L can be
reliably demonstrated. Laboratories that
analyze samples by these three methods
must report quantitative data for
bromate concentrations as low as 0.001
mg/L.
Since EPA Methods 317.0 Revision
2.0, 326.0, and 321.8 offer significantly
greater sensitivity for bromate analyses,
EPA considered whether these should
be the only methods approved for
bromate compliance monitoring.
However, the new methods using
postcolumn reactions with UV/Vis
detection (EPA Methods 317.0 Revision
2.0 and 326.0) or IC/ICP-MS (EPA
Method 321.8) require greater analyst
skill than is necessary for the standard
ion chromatographic (1C) methodology
(EPA Method 300.1 and ASTM Method
D 6581-00). They also require
instrumentation that may not be
currently owned by many laboratories
that perform bromate analyses. As a
result of these factors and because the
standard 1C methods are adequate for
determining compliance with the
bromate MCL that was promulgated as
part of the Stage 1 DBPR, EPA decided
not to propose withdrawal of the
currently approved method {EPA
Method 300.1). In addition, EPA
decided to propose ASTM Method D
6581-00, because it is equivalent to EPA
Method 300.1. EPA strongly encourages
laboratories to expand their services by
adding the capability to perform
analyses using one of the more sensitive
methods for bromate. EPA believes that
there will be a shift to the more
sensitive methods as water systems
realize that the analytical capabilities
are available for a slightly increased
analytical cost. (The ability to determine
bromate concentrations as low as 1 \igl
L will provide water systems more
information concerning the
optimization of ozone application to
control for bromate formation.)
10. Request for Comments
EPA requests comments on whether
the methods proposed today should be
approved for compliance monitoring.
EPA solicits comments as to whether
standardizing the sample holding times
for the HAA5 methods is appropriate.
Specifically, should the sample holding
time for Standard Method 6251 B be
extended from 9 days to 14 days and
should the sample holding time for EPA
Method 552.1 be shortened from 28
days to 14 days?
EPA requests comments as to whether
laboratories should be required to
switch to one of the more sensitive
bromate methods for compliance
monitoring sample analyses. Should
EPA Method 300.1 be withdrawn as a
compliance monitoring method for
bromate and be replaced by EPA
Methods 317.0 Revision 2.0, 326.0, and
321.8 which provide reliable data for
bromate concentrations as low as lug/L?
P. Laboratory Certification and
Approval
1. What Is EPA Proposing Today?
EPA recognizes that the effectiveness
of today's proposed regulation depends
on the ability of laboratories to reliably
analyze the regulated disinfection
byproducts at the proposed MCLs. EPA
has established a drinking water
laboratory certification program that
States must adopt as part of primacy.
Laboratories must be certified in order
to analyze samples for compliance with
the MCLs. EPA has also specified
laboratory requirements for analyses,
such as alkalinity, bromide, disinfectant
residuals, magnesium, TOG, and SUVA,
that must be conducted by parties
approved by EPA or the State. EPA's
"Manual for the Certification of
Laboratories Analyzing Drinking Water"
(USEPA 1997b) specifies the criteria
that EPA uses to implement the
drinking water laboratory certification
program. Today's proposed rule
maintains the requirements of
laboratory certification for laboratories
performing analyses to demonstrate
compliance with MCLs and all other
analyses to be conducted by approved
parties. It revises the acceptance criteria
for performance evaluation (PE) studies
and proposes reporting limits for the
DBFs as part of the certification
program. Today's rule also proposes that
TTHM and HAA5 analyses that are
performed for the IDSE or system-
specific study be conducted by
laboratories certified for those analyses.
2. What Changes Are Proposed for the
PE Acceptance Criteria?
The Stage 1 DBPR specified that in
order to be certified the laboratory must
pass an annual performance evaluation
(PE) sample approved by EPA or the
State using each method for which the
laboratory wishes to maintain
certification. The acceptance criteria for
the DBF PE samples were set as
statistical limits based on the
performance of the laboratories in each
study. This was done because EPA did
not have enough data to specify fixed
acceptance limits.
Subsequent to the 1998 promulgation,
EPA evaluated the results for the EPA
Water Supply (WS) PE studies and the
Information Collection Rule PE studies
to determine if fixed acceptance limits
could now be applied. (Fixed limits
were used during the Information
Collection Rule).
Four different fixed limits (±20%,
±30%, ±40%, and ±50% of the true
value) were applied to each analyte in
the WS PE study TTHM, HAA5,
bromate, and chlorite samples.
Successful analysis of the sample was
defined as passing all four THMs
individually in the TTHM PE sample;
passing four of the five HAAs in the
HAA5 PE sample; and passing bromate
and chlorite individually. The number
and percentage of laboratories that
successfully passed each study sample
were determined for the four fixed
limits. These results were then
evaluated to determine how narrow the
criteria could be set in order to achieve
accurate data and also provide enough
certified laboratories to meet the
capacity needs. Only the last six WS PE
Studies administered by EPA (WS36-
WS41 conducted between 1996-1998)
were used in the final recommendation,
because they provided a better estimate
of current laboratory capabilities. Table
V-19 summarizes the results of this WS
PE Study evaluation.
The number of laboratories that
analyzed WS TTHM PE samples was
significantly larger than for the other
DBFs, because a laboratory certification
program for TTHM has been in effect
since the promulgation of the THM rule
in 1979 (USEPA 1979). Most of the
analytical methods for TTHM have been
in use for many years, and the
laboratories are experienced in their
use. The Stage 1 DBPR established the
first requirements to monitor for the
other DBPs and certification was not
required until December 2001.
Therefore, the WS PE results for HAAS,
chlorite, and bromate were from
laboratories that were not part of a
certification process and the laboratories
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49619
were using methods that were relatively
new. In addition, the method used for
bromate during the WS studies was EPA
Method 300.0 which was replaced by
EPA Method 300.1 in the Stage I DBPR,
because Method 300.1 is more sensitive.
Laboratories would be expected to have
greater success in passing the bromate
PE samples using Method 300.1 and the
bromate methods that are being
proposed in today's rule.
TABLE V-19— FIXED LIMIT EVALUATION OF WS PE STUDIES 36—41
[Average # and % of labs successfully completing studies]
DBP Sample
TTHM
HAA51
±20% of TV
#Labs
609
50
55
45
%Labs
73
37
63
50
±30% of TV
#Labs
731
83
68
52
%Labs
88
61
78
57
±40% of TV
#Labs
773
103
72
57
%Labs
93
75
82
64
±50% of TV
#Labs
788
115
74
60
%Labs
94
84
85
68
1 Study 38 was excluded from this analysis, because a valid DCAA true value was not available for the HAA sample.
Based on the results from the analyses
described previously, EPA believes it is
reasonable to set the TTHM acceptance
criteria at ±20% around the study true
values. The number of laboratories
capable of performing TTHM analyses is
large and the results described
previously show that in the time frame
of 1996-1998, over 70% of the
laboratories could successfully meet the
±20% criteria. The PE studies
conducted during the Information
Collection Rule used the same
acceptance criteria (USEPA 1996b).
The data indicate that ±40% are
probably the tightest criteria that could
be used to evaluate HAAS PE samples.
Setting this criteria balances the need
for approval of enough labs to meet
monitoring capacity and the need to
provide data of acceptable accuracy.
The ±40% criteria is consistent with the
Information Collection Rule PE study
acceptance criteria and it is tighter than
the criteria established in the Stage 1
DBPR. During the Information
Collection Rule, laboratories that were
approved using the ±40% criteria were
able to provide accurate and precise
data as evidenced by the quality control
data collected when the Information
Collection Rule samples were analyzed
(Fair et al 2002). Of the 1,250
Information Collection Rule samples
that were fortified with known amounts
of HAAs, the median recovery was
103% and the recoveries ranged
between 89% and 120% in 80% of the
fortified samples. There were 1,211
Information Collection Rule samples
that were analyzed in duplicate and the
median relative percent difference for
those HAAS analyses was 4%. Ninety
percent of the analyses had RPDs less
than 21%. EPA believes laboratories
that are certified using the ±40% criteria
in PE studies should be capable of
performing at a level comparable to the
Information Collection Rule
laboratories.
EPA believes chlorite PE samples
should be evaluated using a ±30%
criteria. Over 70% of the laboratories
could meet this requirement for chlorite
in the WS studies.
The percentage of passing labs for
bromate is almost 60% when a ±30%
criteria is applied to the WS study data.
Since the data do not accurately reflect
the bromate methods that are now being
used by laboratories, EPA believes a
greater percentage of laboratories would
pass the bromate PE study using today's
technology. Unfortunately, EPA does
not have the data to verify this
assumption, because EPA no longer
conducts PE studies. Even if the
assumption is flawed, a 57% acceptance
rate would still provide enough certified
laboratories to handle the number of
bromate samples required for
compliance monitoring under the Stage
1 DBPR.
The proposed acceptance criteria are
listed in Table V-20.
TABLE V-20.—PROPOSED PERFORMANCE EVALUATION (PE) ACCEPTANCE CRITERIA
DBP
Acceptance
limits
(percent)
Comments
TTHM
Chloroform
Bromodichloromethane
Dibromochloromethane
Bromoform
HAAS
Monochloroacetic Acid
Dichloroacetic Acid
Trichtoroacetic Acid
Monobromoacetic Acid
Dibromoacetic Acid
Chlorite
Bromate
±20
±20
±20
±20
±40
±40
±40
±40
±40
±30
±30
Laboratory must meet all 4 individual THM acceptance limits in
order to successfully pass a PE sample for THMs.
Laboratory must meet the acceptance limits for 4 out of 5 of
the HAAS compounds in order to successfully pass a PE
sample for HAAS.
EPA is also proposing that the PE
acceptance limits described previously
become effective within 60 days of
promulgation of the final rule. This will
allow the laboratory certification
program to implement the fixed limits
as soon as possible. Laboratories that
were certified under the Stage 1 PE
acceptance criteria would be subject to
the new criteria when it is time for them
to analyze their annual DBP PE
samples(s).
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3. What minimum reporting limits are
being proposed?
The Consumer Confidence Reports
Rule (USEPA 1998i) requires that all
detected regulated contaminants be
reported in the annual reports, but
detection is not defined for the DBF
contaminants. This rule addresses the
deficiency by proposing reporting limits
for the regulated DBFs.
Laboratories that analyze compliance
samples must be able to reliably
measure the DBFs at concentrations
below the MCL. Laboratories must also
be able to measure the individual TTHM
and HAAS compounds at levels that are
much lower than the MCLs for these
compound classes, because the MCLs
are based on the sum of the individual
compound concentrations.
Historically, EPA has used practical
quantitation levels to estimate the
lowest concentration at which
laboratories can be expected to provide
data within specified limits of precision
and accuracy during routine operating
conditions (USEPA 1985). The estimates
are based on PE data, if available, or are
set at five or ten times the method
detection level.
In today's rule, EPA is proposing an
alternate approach for establishing the
lowest concentration for which
laboratories are expected to report
quantitative data for DBPs. The
approach is based on a unique data set
from the Information Collection Rule.
Laboratories were required to meet
specific quality control criteria when
they analyzed samples for the
Information Collection Rule. The rule
established a regulatory minimum
reporting level (MRL) for each analyte
and laboratories were required to
demonstrate they could accurately
measure at these concentrations each
time a set of samples was analyzed. The
regulatory MRLs were based on
recommendations from experts who
were experienced in DBF analyses and
were set at concentrations for which
most laboratories were expected to be
able to meet the precision and accuracy
criteria under normal operating
conditions. Most samples were also
expected to contain concentrations
greater than the specified MRLs.
EPA evaluated the data from the
Information Collection Rule to
determine if the laboratories were able
to reliably measure down to the
required MRL concentrations. Precision
and accuracy data from the calibration
check standards prepared at the MRL
concentrations (listed in Table V-21)
were examined. The data indicated most
laboratories were able to provide
quantitative data for samples with these
concentrations.
Because laboratories demonstrated the
capability to meet the Information
Collection Rule MRLs, EPA believes it is
reasonable to expect similar
performance during the analyses of DBF
compliance monitoring samples. In
today's rule, EPA is proposing to
incorporate MRL requirements into the
laboratory certification program for
DBPs and to use regulatory MRLs as the
minimum concentrations that must be
reported as part of the Consumer
Confidence Reports (§ 141.151(d)).
TABLE V-21.—PROPOSED MINIMUM REPORTING LEVEL (MRL) REQUIREMENTS
DBP
TTHM
Chloroform
Bromodichloromethane
Dibromochloromethane
Bromoform
HAAS
Monochloroacetic Acid
Dichloroacetic Acid
Trichloroacetic Acid
Monobromoacelic Acid
Dibromoacetic Acid
Chlorite
Bromate
MRL
Information
collection
rule
(M9/L)
Proposed stage
2DBPR
Comments
Laboratories that use EPA Methods 317.0 Revision
2.0, 326.0, or 321.8 must meet a 1.0 jig/L MRL
for bromate.
As part of the request for certification,
EPA is proposing to require laboratories
to demonstrate they can reliably
measure concentrations at least as low
as the ones listed in Table V-21 in order
to be certified for those parameters. This
would mean that the calibration curve
must encompass the proposed
regulatory MRL concentration and that
the laboratory must verify the accuracy
of the calibration curve at the lowest
concentration for which quantitative
data are reported by analyzing a
calibration check standard at that
concentration prior to analyzing each
batch of samples. (Laboratories would
analyze a check standard at the
specified MRL concentration daily or
each time samples are analyzed.) The
measured concentration for this check
standard must be within ±50% of the
expected value. Laboratories may
choose to report quantitative data at
concentrations lower than the proposed
regulatory MRLs as long as the required
accuracy criteria (±50% of the expected
value) is met by daily analyzing
standards at the lowest reporting limit
chosen by the laboratory.
Laboratories were not given the
opportunity to report concentrations
lower than the specified MRLs during
the Information Collection Rule. Some
laboratories indicated they have met the
precision and accuracy criteria at lower
concentrations, so EPA believes that
each laboratory should have the
flexibility to continue using its own
reporting limits as long as the laboratory
MRLs are not higher than the regulatory
ones proposed in this rule. This
flexibility would minimize the cost of
implementing the regulatory MRL
requirements, because the laboratory
would not have to make changes in its
established quality control procedures
unless its procedures are less stringent
than those being proposed today.
Requiring a laboratory to adopt
regulatory MRLs that are higher than the
laboratory reporting limits currently in
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49621
use offers no advantage and could
increase analytical costs. The capability
to provide quantitative data at the
laboratory's MRL or the regulatory MRL
would need to be demonstrated on a
daily basis by analyzing a check
standard at that concentration and by
achieving a recovery in the range of 50
to 150%.
The proposed regulatory MRL for
MCAA is 2.0 Mg/L based on the
Information Collection Rule
performance data. However, MCAA was
not present at concentrations higher
than this in more than half of the
samples analyzed for HAAs during the
Information Collection Rule (USEPA
2003o). Some laboratories reported that
they could have provided quantitative
data for MCAA down to concentrations
as low as 1.0 ug/L.
EPA is proposing a regulatory MRL
For chlorite that is much higher than can
sasily be achieved using the approved
3r proposed methods. The MRL
specified during the Information
Collection Rule was 20. Ug/L and
laboratories were able to successfully
abtain quantitative data at that level.
However, in the context of this rule,
SPA believes that requiring laboratories
;o verify their calibration curves down
to 20. ug/L each time samples are
analyzed is unnecessary. This is because
chlorite analyses are only performed on
samples from water plants that use
:hlorine dioxide and most of the
upplied chlorine dioxide is converted to
Chlorite, so the concentrations that are
expected in most compliance
nonitoring samples will be much higher
:han 20. ug/L. (The Information
Collection Rule data showed a median
chlorite concentration of 380 ug/L in the
inished water and 333 Ug/L as the
distribution system average in systems
asing chlorine dioxide (USEPA 2003o).)
iPA is proposing a regulatory MRL of
iOO. ug/L for chlorite, because most of
:he samples are expected to contain
concentrations higher than 200. Ug/L.
Fhe MCL for chlorite is 1.0 mg/L (1,000
ig/L). EPA recognizes that setting the
•egulatory MRL for chlorite based on the
concentrations expected to be found in
he samples rather than the sensitivity
jf the analytical method is inconsistent
tfith the approach taken for other
compounds in this rule. Nevertheless,
SPA believes setting the MRL based on
iccurrence information is appropriate
jecause it will not compromise the
:ompliance data. Water systems would
lave the option of requiring that
aboratories establish a lower reporting
imit when their samples are analyzed
ind EPA would encourage this in cases
n which the samples consistently
:ontain chlorite concentrations that are
<200. Ug/L. If a lower reporting limit is
used, then the laboratory will be
required to meet the precision and
accuracy requirements at that lower
concentration by daily successfully
analyzing a check standard at the
laboratory reporting limit concentration
prior to analyzing compliance samples.
EPA believes very few water systems
will request more sensitive chlorite
analyses, because their samples won't
have low enough concentrations to
require it.
EPA is proposing two regulatory
MRLs for bromate analyses in today's
rule. This is because the traditional ion
chromatographic (1C) methods using
conductivity detection (EPA Method
300.1 and ASTM Method 6581-00) are
only capable of quantitating down to 5.0
Ug/L while the new 1C methods using
either post column reactions with UV/
Vis detection (EPA Methods 317.0
Revision 2.0 and 326.0) or 1C followed
by ICP-MS detection (EPA Method
321.8) can reliably quantitate bromate
concentrations as low as 1.0 ug/L. EPA
believes it is appropriate to set the
regulatory MRL based on the capability
of the method. (EPA has published
detection limits for inorganic
contaminants based on method
capability (§ 141.23(a)(4)(i)J, so the
approach proposed today is consistent
with previous regulations.) If the
regulatory MRL is based on the most
sensitive method, then the routine 1C
methods could no longer be used even
though they are adequate for
demonstrating compliance with the
bromate MCL. If the regulatory MRL is
set using the least sensitive method,
then the feasibility for reduced bromate
monitoring based on a running annual
average of <0.0025 ug/L (<2.5 Ug/L)
would not be adequately demonstrated
based on data reported with a reporting
limit of 5.0 Ug/L.
EPA is proposing MRLs as part of the
certification process. Laboratories
would be required to demonstrate they
can reliably quantitate at the specified
MRL concentration when their current
DBF certification is subject to renewal
or if they are applying for certification
for DBP methods for the first time.
(Demonstration would be accomplished
by providing precision and accuracy
data from the analyses of check
standards at or below the regulatory
MRL concentration over a several day
period. The laboratory's standard
operating procedure for HAAS analyses
would include a requirement to daily
meet the MRL accuracy criteria for a
check standard at orbeiow the
regulatory MRL concentration.)
Although ensuring laboratories can meet
the regulatory MRLs is a new
certification requirement, EPA does not
believe this significantly increases the
time required to review a laboratory
prior to certification. Each DBP method
requires the laboratory to generate a
similar set of data at a higher
concentration and to meet specific
accuracy and precision criteria as part of
the initial demonstration of laboratory
capability to perform the method;
review of the MRL data set will be
comparable to what is already being
done. This new requirement will ensure
that laboratories can reliably analyze
samples that contain low concentrations
of DBFs on an on-going basis.
EPA is also proposing to require the
regulatory MRLs be used for compliance
reporting by the Public Water Systems.
Finally, the regulatory MRLs would be
used when Public Water Systems inform
customers of their water quality relative
to DBP concentrations in the annual
Consumer Confidence Reports.
4. What Are the Requirements for
Analyzing IDSE Samples?
EPA is proposing that the TTHM and
HAA5 samples collected for the Initial
Distribution System Evaluations (IDSE)
and the system specific studies
conducted in lieu of IDSEs be analyzed
by certified laboratories. EPA recognizes
that this will require additional
laboratory capacity during the time
period in which these studies are
conducted. The largest challenge will be
in developing the capacity to analyze
the samples for the water systems that
must complete the studies, analyze the
data, and recommend Stage 2 DBP
sampling sites within two years of the
promulgation date of the rule. However,
EPA believes commercial laboratories,
in particular, will be able to expand
their capacity to meet the demand based
in the information presented below.
Assuming no waivers or system-
specific studies, the number of IDSE
samples is estimated to be between
14,000 and 21,000 per month in the first
round of IDSE monitoring, depending
on whether the monitoring requirements
are based on population or number of
treatment plants, respectively.
Laboratories should easily be able to
accommodate this increase in TTHM
samples, because experience performing
TTHM analyses is spread across a large
number of laboratories. Hundreds of
laboratories have been certified for
TTHM analyses, since certification was
first required in 1979. There were close
to 600 laboratories certified to perform
TTHM analyses in 1991. In the 1996-
1998 period, there were over 800
laboratories participating in the PE
studies for TTHMs and 600 of those
laboratories were capable of meeting the
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Federal Register/Vol. 68, No. 159 /Monday, August 18, 2003/Proposed Rules
TTHM PE acceptance criteria proposed
in today's rule. Many water system
laboratories are certified to perform
TTHM analyses and will be able to
incorporate the IDSE TTHM samples
from their systems into the laboratory
schedule. It is reasonable to expect that
commercial laboratories will be able to
handle the remainder of the TTHM
samples. (EPA does not have a current
estimate of the number of laboratories
certified to perform TTHM analyses.
However, if the number of IDSE samples
from large systems was evenly spread
over the 600 laboratories that were
certified in 1991, this would be less
than 40 additional samples per month
for each laboratory. Analysis of 40
TTHM samples would involve less than
two days of analyst and instrument time
which does not seem unreasonable for
commercial laboratories to
accommodate.)
Analyses of the HAAS samples will
present a greater challenge, because
certification is relatively new for this
measurement. EPA anticipates that most
of the HAAS samples will be analyzed
by commercial and Slate laboratories,
because the methods are more complex
than the TTHM analyses and monitoring
was not widely required until January
2002. Laboratories were not required to
be certified to perform HAAS analyses
until January 2002. However, the PE
Study results from 1996-4998 indicate
that over 130 laboratories were
performing HAAS analyses during that
time frame and approximately 100 of
those laboratories were capable of
meeting the HAAS PE acceptance
criteria proposed in today's rule.
Ninety-four laboratories were approved
to perform HAA analyses during the
Information Collection Rule; twenty-
seven of them were commercial
laboratories and nine were State
laboratories. EPA anticipates that large
commercial laboratories already
certified to perform HAA5 analyses will
recognize this market potential and add
staff and instrumentation to
accommodate the increased demand.
Most systems serving <10,000 people
will not begin their IDSE studies until
after the large systems have completed
their studies. Even though the potential
number of samples is greater, the small
systems have two additional years in
which to complete their studies, so
there is more opportunity to schedule .
the sampling in such a manner that
laboratory capacity is maintained. The
laboratory capacity should be readily
available by the time analyses of these
samples are required.
5. Request for Comments
EPA requests comments concerning
the appropriateness of the proposed PE
acceptance criteria.
EPA solicits comments as to whether
an MRL lower than 2 ng/L is feasible for
MCAA and if so, what should that MRL
concentration be?
EPA requests comments concerning
whether the MRL for chlorite should be
based on the sensitivity of the method
(i.e., 20. ug/L) or on the expected
concentration range of the samples (i.e.,
200. ug/L).
EPA solicits comments concerning
which MRL approach should be
considered forbromate. Specifically,
should EPA set the MRL based on the
capability of the method which would
mean that two different MRLs are
defined or should one MRL be
established based on either the least or
most sensitive method?
EPA requests comments concerning
the appropriateness of the MRL
certification requirements and whether
additional certification requirements
should be considered.
EPA solicits comments on the
availability of laboratory capacity to
perform TTHM and HAAS analyses for
IDSE studies.
VI. State Implementation
This section describes the regulations
and other procedures and policies States
would have to adopt to implement the
Stage 2 DBPR, if finalized as proposed
today. States must continue to meet all
other conditions of primacy in 40 CFR
part 142.
The SDWA establishes requirements
that a State or eligible Indian Tribe must
meet to assume and maintain primary
enforcement responsibility (primacy) for
its public water systems. These SDWA
requirements include: (1) adopting
drinking water regulations that are no
less stringent than Federal drinking
water regulations, (2) adopting and
implementing adequate procedures for
enforcement, (3) keeping records and
making reports available on activities
that EPA requires by regulation, (4)
issuing variances and exemptions (if
allowed by the State), under conditions
no less stringent than allowed under the
SDWA, and (5) adopting and being
capable of implementing an adequate
plan for the provision of safe drinking
water under emergency situations.
General rule implementation activities
include notifying systems of rule
requirements, updating internal and
external databases, providing training
and technical assistance, and reviewing
(and, if necessary, approving)
monitoring and other reports and plans.
To receive primacy for the Stage 2
DBPR, when final, States will be
required to adopt the following new or
revised requirements under their own
regulations:
—Section 141.33(a) and (f), Record
maintenance;
—Section 141.64, MCLs for disinfection
byproducts;
—Subpart L, Disinfectant Residuals,
Disinfection Byproducts, and
Disinfection Byproduct Precursors;
—Subpart O, Consumer Confidence
Reports;
—Subpart Q, Public Notification of
Drinking Water Violations;
—Subpart U, Initial Distribution System
Evaluation; and
—Subpart V, Stage 2B Disinfection
Byproducts Requirements.
In addition to adopting basic primacy
requirements specified in 40 CFR part
142, States are required to address
applicable special primacy conditions.
Special primacy conditions pertain to
specific regulations where
implementation of the rule involves
activities beyond general primacy
provisions. The purpose of these special
primacy requirements in today's
proposal is to ensure State flexibility in
implementing a regulation that: (1)
Applies to specific system
configurations within the particular
State and (2) can be integrated with a
State's existing Public Water Supply
Supervision Program. States must
include these rule-distinct provisions in
an application for approval or revision
of their program. These primacy
requirements for implementation
flexibility are discussed in the following
section.
A. State Primacy Requirements for
Implementation Flexibility
To ensure that a State program
includes all the elements necessary for
an effective and enforceable program
within that State under today's rule, a
State primacy application must include
a description of how the State will
review IDSE reports and approve new or
revised monitoring sites for long-term
DBP compliance monitoring. If a State
will use the authority to grant blanket
waivers for IDSE requirements to very
small systems, it must comply with the
special primacy provision for granting
such waivers. A State that intends to use
the authority for addressing consecutive
system monitoring requirements must
include a description of how it intends
to implement that authority. A State
primacy application must also include a
description of how the State will require
systems to identify significant
excursions.
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49623
3. State Recordkeeping Requirements
The current regulations in § 142.14
equire States with primacy to keep
Carious records, including analytical
esults to determine compliance with
ACLs, MRDLs, and treatment technique
equirements; system inventories; State
ipprovals; enforcement actions; and the
ssuance of variances and exemptions.
e proposed Stage 2 DBPR requires
hat the State keep records related to
ny decisions made pursuant to the
equirements in subparts U and V, plus
;opies of IDSE reports submitted by
ystems until those reports are reversed
ir revised in their entirety. Today's
troposal also includes a revision to the
itate recordkeeping requirements that
equires States to maintain records of
)BP monitoring plans submitted by
lublic water systems until superceded
y a new system monitoring plan.
". State Reporting Requirements
EPA currently requires in § 142.15
bat States report information such as
iolations, variance and exemption
tatus, and enforcement actions to EPA.
'he proposed Stage 2 DBPR will not
dd any additional reporting
squirements.
?. Interim Primacy
On April 28,1998, EPA amended its
itate primacy regulations at 40 CFR
42.12 to incorporate the new process
ientified in the 1996 SDWA
tmendments for granting primary
nforcement authority to States while
leir applications to modify their
rimacy programs are under review (63
R 23362) (USEPA 1998J). The new
rocess grants interim primary
nforcement authority for a new or
vised regulation during the period in
/hich EPA is making a determination
nth regard to primacy for that new or
vised regulation. This interim
nforcement authority begins on the
ate of the complete primacy
pplication submission or the effective
ate of the new or revised State
jgulation, whichever is later, and ends
'hen EPA makes a final determination.
lowever, this interim primacy authority
; only available to a State that has
rimacy for every existing NPDWR in
Ffect when the new regulation is
romulgated.
As a result, States that have primacy
>r every existing NPDWR already in
:fect may obtain interim primacy for
lis rule, beginning on the date that the
tate submits the application for this
lie to EPA, or the effective date of its
svised regulations, whichever is later.
i addition, a State which wishes to
rtain interim primacy for future
NPDWRs must obtain primacy for this
rule.
E. IDSE Implementation
As discussed in section V.J., many
systems will be performing certain IDSE
activities prior to their State receiving
primacy. During that period, EPA will
act as the primacy agency, but will
consult and coordinate with individual
States to the extent practicable and to
the extent that States are willing and
able to do so. In addition, prior to
primacy, States may be asked to assist
EPA in identifying and confirming
systems that are required to comply
with certain IDSE activities. Once the
State has received primacy, it will
become responsible for IDSE
implementation activities.
F. State Burden
Section VII of today's document
contains an analysis of the burden that
this rule will place on States in
receiving primacy and implementing
this rule.
G. Request for Comment
EPA requests comment on the State
implementation requirements including
the special primacy requirements.
VII. Economic Analysis
This section summarizes the Health
Risk Reduction and Cost Analysis
(HRRCA) in support of the Stage 2 DBPR
as required by section 1412(b)(3)(C) of
the 1996 SDWA. In addition, under
Executive Order 12866, Regulatory
Planning and Review, EPA must
estimate the costs and benefits of the
Stage 2 DBPR in an Economic Analysis
(EA). EPA has prepared an EA to
comply with the requirements of this
order and the SDWA Health Risk
Reduction and Cost Analysis (HRRCA)
(USEPA 2003i). SDWA (Section 1412
(b)(4)(C)) also requires the Agency to
determine that the benefits of the
promulgated rule would justify the costs
of compliance. The proposed EA is
available in the docket and is also
published on the Agency's web site:
h ttp://www.epa.gov/edocket.
It is important to note that the
regulatory options considered by the
Agency are the direct result of an
Advisory Committee process that
involved various drinking water
stakeholders. More information on this
process is discussed in sections II and
V of today's preamble.
In order to analyze both benefits and
costs of the proposed rule and other
regulatory alternatives considered by
the Agency, EPA relied on several data
sources to understand DBF occurrence,
an analytical model to predict treatment
changes and changes in DBP
occurrence, and input and analysis from
expert technical review panels to assist
with model validation and technology
selection. A brief description of the
process is outlined in section VILE, but
a more detailed explanation of the
analytical process is in the EA for the
proposed Stage 2 DBPR (USEPA 2003i).
The Stage 2 DBPR economic impact
analysis uses a model, (referred to as the
Surface Water Analytical Tool or
SWAT) and information collected under
the Information Collection Rule to make
predictions about finished water and
delivered water DBP levels, as well as
predicting technology changes
necessary for systems to comply with
rule alternatives. Specifically, SWAT
estimates post-Stage 1 DBPR (pre-Stage
2} and post-Stage 2 DBPR DBP levels
and likely technology choices by the
industry to achieve compliance. For
smaller systems and for all ground water
systems, expert panels considered
occurrence data and current treatment
technology specific to these systems and
used this information to predict
technology treatment changes that may
result from this proposed rule.
Both benefits and costs are presented
as annualized values. The process
allows comparison of cost and benefit
streams that are variable over a given
time period. The time frame used for
both benefit and cost comparisons is 25
years; approximately five years account
for rule implementation and 20 years for
the average useful life of the equipment.
The Agency uses social discount rates of
both three percent and seven percent to
calculate present values from the stream
of benefits and costs and also to
annualize the present value estimates.
The EA for the proposed rule (USEPA
2003i) also shows the undiscounted
stream of both benefits and costs over
the 25 year analysis period.
A. Regulatory Alternatives Considered
by the Agency
Today's proposed Stage 2 DBPR
represents the second of a set of rules
that address public health risks from
DBFs. The Stage 1 DBPR was
promulgated to decrease average
exposure to DBFs and associated health
risks by focusing compliance on MCLs
based on average concentrations of
TTHM and HAAS within the
distribution system. Today's proposed
Stage 2 DBPR further reduces exposure
to chlorinated DBFs by basing
compliance on the LRAA of TTHM and
HAAS concentrations at each sampling
point within the distribution system.
Section V illustrated the LRAA concept
and differences in the two compliance
calculation methodologies. In addition,
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section V provided a comparison of the
regulatory options considered. This
subsection will summarize the
comparison of options and subsection
VILB. will outline the exposure analyses
that led EPA to propose the preferred
option and will present the predicted
national occurrence distributions that
were used to quantify predicted
exposure reductions from today's
proposed rule. A detailed discussion of
EPA's exposure analyses can be found
in the Economic Analysis for the Stage
2 DBPR (USEPA 2003i).
There are two components in the
Agency's M-DBP regulatory
development process that are
particularly relevant to evaluation of
options discussed in today's proposal:
(1) the data synthesis and evaluation
resulting from the Information
Collection Rule; and (2) the analysis and
recommendations of the M-DBP
Advisory Committee. Data from the
Information Collection Rule were used
with the SWAT model to estimate the
national distributions of DBP
occurrence. The Advisory Committee
considered several questions during the
negotiation process, including:
—What are the remaining health risks
after implementation of the Stage 1
DBPR?
—What are approaches to addressing
these risks?
—What are the risk tradeoffs that need
to be considered in evaluating these
approaches?
—How do the estimated costs of the
approach compare to reductions in
peak occurrences and overall
exposure for that approach? How does
this measure (ratio of costs to
exposure reduction) compare among
the approaches?
The Advisory Committee considered
the DBP occurrence estimates and
characteristics of these distributions to
be important in understanding the
nature of public health risks. Although
the Information Collection Rule data
were collected prior to promulgation of
the Stage 1 DBPR, the data support the
concept that a system could be in
compliance with the Stage 1 DBPR
MCLs of 0.080 mg/L and 0.060 mg/L for
TTHM and HAAS, respectively, and yet
have points in the distribution system
with either periodically or consistently
higher DBP levels (see section IV).
Based on these findings, and in order
to address disproportionate risk within
distribution systems, the Advisory
Committee discussed an array of options
that would base compliance on
exposure at specific sampling locations
rather than on average exposures for the
entire distribution system. These
included options for determining
compliance as an LRAA (requiring
systems to meet the MCL at individual
sampling locations as a running annual
average) or as absolute maximums
(requiring that no samples taken exceed
the MCL concentration), in addition to
a combination of these approaches. For
example, the Advisory Committee
reviewed the exposure reductions for a
number of approaches based on
different LRAA and absolute maximum
incremental MCL levels, and
combinations of an LRAA approach
with a companion absolute maximum
for a variety of different concentration
levels. The Advisory Committee also
evaluated the associated technology
changes and costs for these alternatives.
In the process of narrowing down
alternatives based on this vast amount
of information, the Advisory Committee
primarily focused on four types of
alternative rule scenarios illustrated
next.
Preferred Alternative
—Long-term MCLs of 0.080 rng/L for
TTHM and 0.060 mg/L for HAAS as
LRAAs.
—Bromate MCL remaining at 0.010 mg/
L.
Alternative 1
—Long-term MCLs of 0.080 mg/L for
TTHM and 0.060 mg/L for HAAS as
LRAAs.
—Bromate MCL of 0.005 mg/L.
Alternative 2
—Long-term MCLs of 0.080 mg/L for
TTHM and 0.060 mg/L for HAAS as
absolute maximums for individual
measurements.
—Bromate MCL remaining at 0.010 mg/
L.
Alternative 3
—Long-term MCLs of 0.040 mg/L for
TTHM and 0.030 mg/L for HAAS as
anRAA.
—Bromate MCL remaining at 0.010 mg/
L.
Figure VII—1 shows how compliance
would be determined under each of the
TTHM/HAA5 alternatives described and
the Stage 1 DBPR for a hypothetical
large surface water system. This
hypothetical system has one treatment
plant and measures TTHM in the
distribution system in four locations per
quarter (the calculation methodology
shown would be the same for HAAS).
Ultimately, the Advisory Committee
recommended the Preferred Alternative
in combination with an IDSE
requirement.
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49625
Figure VI!-1. Calculations of Compliance for the Regulatory Alternatives Considered
I iBasis of Compliance
Violation of MCL
Stage 1 DBPR
TTHM MCL = 80 ug/L measured as an RAA
No exceedance of MCL
Q1
Q2
Q3
Q4
LOG, 1
100
75
55
60
L Loc. 2
40
50
45
55
LOG. 3
50
40
55
40
LOG. 4
50
100
110
75
RAA
Qtriy Avg.
60
66
66
58
r 63 "~l
Preferred Stage 2 DBPR Alternative and Alternative 1*
TTHM MCL = 80 M9/L measured as an LRAA
LRAA at Location 4 exceeds MCL
Q1
Q2
Q3
Q4
LRAA
^•MBH^^H
Loc. 1
100
75
55
60
—7"]
Loc. 2
40
50
45
55
[ 48
Loc. 3
50
40
55
40
Li"4!.:
Loc. 4
50
100
110
75 . |
84 |
*The Preferred Alternative and Alternative 1 have the same TTHM MCL;
they differ only in regard to the bromate MCL
Alternative 2
TTHM MCL = 80 ug/L measured as a single Highest value
Three samples at Locations 1 and 4 exceed MC.L
1 Loc. 1
Q1 [i 100 |
Q2 | 75 j
Q3 1 55 J
Q4 | 60 I
Loc. 2 j Loc. 3
40 ! 50 j
50 |__ 40
45 | 55
55 | 40
Loc. 4
50
100
110
I 75 J
Alternative 3
TTHM MCL = 40 ug/L measured as an RAA
RAA exceeds MCL
Q1
Q2
Q3
Q4
Loc. 1
100
75
55
60
Loc. 2
40
50
45
55
LOG. 3
50
40
55
40
Loc. 4
50
100
110
75
RAA
Qtrly Avg.
60
66
66
58
63
The Preferred Alternative, coupled
ith the IDSE's refocused sampling (see
ction V), was recommended by the
dvisory Committee because this
>proach addresses the objective of
ducing potential adverse reproductive
nd developmental health risks. It
chieves this objective by controlling
eak TTHM and HAA5 concentrations
sites throughout the distribution
system without compromising microbial
protection. At the same time, it will
only require a few higher risk systems
to face the cost of employing additional
advanced technologies. While this
alternative controls the occurrence of
consistently high DBF levels, it is still
possible that individual samples could
exceed the MCL, and consumers could
thus be exposed to higher DBF
concentrations for some portion of the
year. In addition, this alternative will
further reduce average DBF levels as
systems make changes to reduce these
peak concentrations. Subsection VII.B.
will show how today's proposed
requirements are predicted to decrease
exposure risks. The benefits and costs of
each alternative are presented in
subsections VII.C. through VILE.
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
B. Rationale for the Proposed Rule
Option
DBP concentrations can be highly
variable throughout a distribution
system and over time at the same
location in a distribution system
(USEPA 2003o). The determination of
compliance with an RAA under the
Stage 1 DBPR requires a system to
average all of their spatially-distributed
samples collected in one quarter of the
year and to combine this average
concentration with the three prior
quarterly averages determined by the
system. Thus, the RAA-based standard
allows utilities to average spatial and
temporal variability in TTHM and
HAAS samples to determine
compliance, as shown in figure VII-1.
This allows lower results found,
perhaps, nearer a water treatment plant
to offset higher results that might be
found at the ends of the distribution
system. In addition, systems with
multiple plants of differing water
quality (either multiple surface water
plants or surface and ground water
plants) may have particular plant
distribution system sampling locations
with high DBFs that are offset by lower
measurements observed in the portion
of the distribution network served by
other plants.
Under the Stage 2 DBPR proposed
today, TTHM and HAA5 MCLs will
remain the same, but compliance will be
based on a locational running annual
average (LRAA) for each of the sampling
sites in the distribution system, In
addition, the IDSE requirement will
increase the probability that the
compliance sampling sites will capture
the highest DBF levels in the
distribution system. Thus, the reduction
in DBF exposure from the Stage 1 DBPR
to the proposed Stage 2 DBPR results
from the revised requirements for
compliance calculations combined with
new compliance monitoring sites.
EPA expects the Stage 2 DBPR, as
proposed, will result in health benefits
by reducing the estimated health risks
associated with the following exposures:
—Individual TTHM/HAA5 occurrences
significantly exceeding 0.080 mg/L
and 0.060 mg/L;
—Chronic exposures at individual
distribution system locations that
average more than 0.080 mg/L and
0.060 mg/L;
—Chronic exposures at all locations in
the distribution system by reducing
overall system average DBF
concentrations; and
—Chronic and peak exposures in
consecutive systems (systems that
purchase treated water from another
system).
Under the Stage 1 DBPR, high DBF
concentrations at specific locations in
the distribution system could be masked
by spatial and temporal averaging. As
discussed in subsection VII.C, short
term exposures resulting from these
high concentrations may be of concern
in regard to potential adverse
reproductive and developmental health
effects. Chronic exposures at locations
having repeated high DBF
concentrations may be of concern for
cancer endpoints as well. The
remainder of this subsection will
illustrate how today's proposed rule is
expected to reduce "peak" and average
exposures to address these health
concerns.
1. Reducing Peak Exposure
EPA used Information Collection Rule
data to estimate the reduction in
exposure to DBF peaks resulting from
the Stage 2 DBPR. Because the
Information Collection Rule data
represent pre-Stage 1 DBPR conditions,
subsets of those plants already in
compliance with the Stage 1 DBPR and
Stage 2 DBPR were used to estimate pre-
Stage 2 and post-Stage 2 occurrence
respectively. By comparing these
subsets of data, EPA estimated that
approximately 69% of plant locations
having TTHM peaks greater than 0.080
mg/L remaining after the Stage 1 DBPR
could be reduced through
implementation of the Stage 2 DBPR.
EPA conducted this additional peak
reduction analysis only for TTHMs and
not HAA5s because current
epidemiological data only considers the
association between TTHM exposure
and adverse health impacts (see
subsection VII.C). Additional
information on reduction of peak
exposures can be found in section 5.4.1
of the Economic Analysis (USEPA
2003i). EPA recognizes that temporal
and spatial variability in systems that
need to install treatment to comply with
the Stage 1 DBPR may be different than
in those that do not, perhaps due to low
source water TOC concentrations.
However, EPA does not have data
representing DBF levels post-Stage 1.
EPA requests comment on its approach
of using data from plants in compliance
with Stage 1 DBPR requirements
without implementing additional
treatment as a proxy for post-Stage 1
DBF levels.
2. Reducing Average Exposure
To quantify the benefits of today's
proposed rule, EPA compared predicted
post-Stage 2 DBPR occurrence and
compared this to the predicted baseline
concentrations after the Stage 1 DBPR to
determine reductions in exposure
resulting from the Stage 2 DBPR. The
SWAT model was the main tool used in
this analysis. SWAT results were used
directly for medium and large surface
water systems. For small surface water
systems and all ground water systems.
Adjustments were made to the SWAT
results to account for different
percentages of plants changing
technology to meet Stage 2 DBPR
requirements. The Economic Analysis
for today's proposed rule (USEPA 2003i;
provides an in-depth discussion of this
analysis.
Table VII-2 shows the reduction in
average plant-level TTHM and HAAS
concentrations estimated to result from
the Stage 2 DBPR. EPA expects average
DBF levels to decline by 4.7 percent for
all surface water systems. DBP averages
are expected to decline by 2.2 percent
for all large ground water systems and
1.7 percent for all small ground water
systems. These estimates include both
systems already in compliance with the
Stage 2 DBPR and systems making
treatment changes to comply with the
rule. The Agency uses these national
average reductions to quantify the
primary benefit of this rule which is the
estimated range of reduction in bladder
cancer cases nationally. Systems making
treatment changes to comply with the
rule will experience significantly greater
estimated average reductions than the
national average for all systems. Chapter
5 of the EA (USEPA 2003i) includes a
more detailed discussion of this
analysis.
TABLE VII-2.—REDUCTION IN AVERAGE DBP LEVELS FROM PRE-STAGE 2 TO POST-STAGE 2 {ALL PLANTS)
Source water
SW
System size
(population
served)
< 10.000
Average plant-level TTHM concentrations
(H9/L)
Pre-stage 2
35.5
Post-stage
2
33.8
Percent
reduction
4.7
Average plant-level HAA5 concentrations
(H9/L)
Pre-stage 2
25.0
Post-stage
2
23.8
Percent
reduction
4.7
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
49627
TABLE VII-2.—REDUCTION IN AVERAGE DBF LEVELS FROM PRE-STAGE 2 TO POST-STAGE 2 (ALL PLANTS)—Continued
Source water
iW
System size
(population
served)
> 10,000
< 10,000
10,000
Average plant-level TTHM concentrations
(H9/L)
Pre-stage 2
35.5
16.0
16.2
Post-stage
2
33.8
15.6
16.0
Percent
reduction
4.7
2.2
1.7
Average plant-level HAA5 concentrations
(H9/I-)
Pre-stage 2
25.0
8.5
8.6
Post-stage
2
23.8
8.3
8.5
Percent
reduction
4.7
2.2
1.7
Note: Due to rounding, percent reductions calculated from data in the tables may differ from the actual values presented here
Source: Economic Analysis (USEPA 2003i) Exhibit 5.22b
7. Benefits of the Proposed Stage 2
~>BPR
As described previously, the Stage 2
BPR is expected to reduce both peak
nd long-term exposure to DBFs,
lereby reducing the potential risk of
oth adverse reproductive and
evelopmental health effects and
ladder cancer. As discussed in section
I of this preamble, both
aidemiological and toxicological
vidence suggest a possible increased
sk for pregnant women and their
etuses who are exposed to DBFs in
rinking water. The Agency believes
nd the Advisory Committee concluded
lat the weight of evidence is enough to
ke regulatory action to help address
le potential reproductive and
evelopmental endpoints in the Stage 2
BPR. However, data are not available
this time to conduct a traditional
uantitative risk assessment. Instead,
le benefits from reducing most
eproductive and developmental risks
re discussed qualitatively in this
preamble. For one endpoint, fetal loss,
the Agency provides an illustrative
calculation to explore the implications
of some published results for potential
benefits associated with reducing fetal
losses that may be attributable to certain
DBF exposures.
In addition to achieving greater
protection from possible adverse
reproductive and developmental health
effects, the rule may provide additional
reduction in bladder cancer cases as the
overall level of DBFs in distribution
systems nation-wide decreases. The
Agency estimated and monetized the
potential benefits from reduction in
bladder cancers resulting from this rule.
Reductions in bladder cancer (including
both fatal and non-fatal cases) provide a
range of annualized present value
benefits from SO to $986 million using
a three percent discount rate ($0 to $854
million using a seven percent discount
rate) depending on the risk level
assumed. These estimates are based on
the assumption that the percent
reductions in TTHM and HAAs will
correspond to the percent reductions in
bladder cancer risk attributed to
populations receiving chlorinated
drinking water as indicated by various
epidemiology studies (USEPA 1998a).
Zero is included in this range because
of the inconsistent evidence regarding
the association between exposure from
DBFs and cancer.
Other regulatory alternatives
considered by the FACA committee and
the Agency could provide greater
benefits but with greater technology cost
implications. Table VTJ-3 presents
benefits estimates of the proposed Stage
2 DBPR using two population
attributable risks derived from
published studies (2% and 17%) and
assuming there is a causal link between
DBF exposure and bladder cancer. In
subsection VII.G., Table VH-14 shows
potential benefits of all regulatory
alternatives considered by the Agency.
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
Table VII-3. Benefits Summary for the Stage 2 DBPR, Preferred Regulatory Alternative
(Millions, 2000$)
Adverse Reproductive and Developmental Health Effects Avoided
Causality has not been established, and numbers and types of cases avoided, as well as the value of such
cases, were not quantified in the primary benefits analysis. Given the numbers of women of child bearing
age exposed (58 million), the evidence indicates that the number of cases and the value of preventing those
cases could be significant. See results of the illustrative calculation in VI! .C.1 .
Number and Value of Estimated Bladder Cancer Cases Avoided 1
Causality has not been established; however, the weight of evidence supports PAR estimates of potential
benefits. Zero is within the range of potential benefits, but evidence indicates that both the number of cases
and the value of preventing those cases could be significant (see below).
PAR
2%
17%
Annual
Average
Cases
Avoided
20.9
182.2
Discount
Rate, WTP for
Non -Fatal
Cases
3%,
Lymphoma
7 % Lymphoma
3 % Bronchitis
7 % Bronchitis
3%,
Lymphoma
7 % Lymphoma
3 % Bronchitis
7 % Bronchitis
Annualized Benefits of Cases Avoided (90 % Confidence Bounds 2)
Value of Fatal Cases
Avoided
$42.8
($7.1 - 97.4)
$37.1
($6.1 - 84.4)
$42.8
($7.1-97.4)
$37.1
($6.1-84.4)
$373.8
($61.8-850.3)
$323.9
($53.6 - 736.7)
$373.8
($61.8-850.3)
$323.9
($53.6 - 736.7)
Value of Non-Fatal
Cases Avoided
$70.2
($10.9-160.7)
$60.8
($9.4-139.3)
$12.1
($5.4 - 22.2)
$10.5
($4.7-19.2)
$612.4
($94.8-1,403.1)
$530.6
($82.1-1,215.6)
$105.5
($47.5-193.5)
$91.6
($41.2-167.9)
Value of Total
Cases Avoided
$113.0
($17.9-258.2)
$97.9
($15.6-223.7)
$54.9
($12.5-119.6)
$47.6
($10.9-103.7)
$986.2
($156.6-2,253.4)
$854.4
($135.8-1.952.3)
$479.3
($109.3-1.043.7)
$415.5
($94.9 - 904.6)
Other Health Benefits
Qualitative assessment indicates that the value of other health benefits could be positive and significant.
Non-Health Benefits
Qualitative assessment indicates that the value of non-health benefits could be positive.
1. Based on TTHM as indicator. EPA recognizes that the lower bound estimate may be as low as zero since causality
has not yet been established between exposure to chlorinated water and bladder cancer.
2. The 90 percent confidence bounds shown in the exhibit reflect uncertainty in the VSL, WTP, and income elasticity
adjustment.
Source: Economic Analysis (USEPA 2003i) Exhibit 5.27. Detail may not add to totals due to independent rounding.
It is important to note that the
monetized benefits only reflect
estimated benefits from reductions in
bladder cancer. As shown in subsection
VH.C.l.and in Table VII-3, there may be
significant nonquantifiable benefits
associated with regulating DBFs in
drinking water. Were EPA able to
quantify some of the currently
nonquantifiable health effects and other
benefits potentially associated with DBF
regulation, monetized benefits estimates
could be significantly higher than what
is shown in the table. A complete
discussion of how EPA calculated the
risks and the corresponding health
benefits potentially associated with
exposure to DBFs in drinking water can
be found in the Stage 2 DBPR EA
(USEPA 2003i).
For additional perspective EPA used
updated cancer risk factors for four
DBFs for which we have toxicological
data. Table III-3 (see section III of this
preamble) shows the estimated pre-
Stage 2 concentrations of these four
compounds and the estimated number
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49629
of people exposed to them. The Agency
used these four DBFs to calculate an
alternative baseline number of annual
pre-Stage 2 cancer cases. The
calculations use the linearized
multistage model and predict 37 cases
for the EDio risk factors and 87 cases for
the LEDio risk factors. The EDio risk
factors (also known as the maximum
likelihood estimate) are based on the
estimated dose that the model predicts
will result in a carcinogenic response in
10 percent of the subjects, while LEDio
risk factors correspond to the lower 95%
confidence bound on the dose that the
model predicts will result in a
carcinogenic response in 10% of the
subjects (LEDio is EPA's more
conservative and more commonly used
expression of lexicologically based
cancer risk). Assuming that DBF risk
reductions for Stage 2 for the entire
population average 4.2% (corresponding
to the reduction in average TTHM
levels), Stage 2 cancer cases avoided
based on the toxicological data range
from 1.7 to 4.0 cases per year. Section
5.2.2.2 of the Economic Analysis
(USEPA 2003i) presents a more detailed
basis for the derivation of these
estimates. It is important to note that
these estimates do not include risks
from dermal or inhalation exposure nor
do they account for many other DBFs (or
the mixture of DBFs seen in actual
PWSs) for which occurrence or
toxicological risk data do not exist.
1. Non-Quantifiable Health and Non-
Health Related Benefits
Although there are significant
monetized benefits that may result from
this rule from the reduction in bladder
cancer, other important potential
benefits of this rule are not quantified
including potential reductions in
adverse reproductive and
developmental effects and other
cancers.
The primary purpose of the Stage 2
DBPR is to address potential adverse
reproductive and developmental health
sffects that might be associated with
DBF exposure. EPA concludes that, "the
pidemiologic data, although not
conclusive, are suggestive of potential
developmental, reproductive, or
:arcinogenic health effects in humans
xposed to DBFs" (Simmons et al 2002).
SPA does not believe the available
evidence provides an adequate basis for
quantifying potential reproductive/
ievelopmental risks. Nevertheless,
;>iven the widespread nature of exposure
:o DBFs and the priority our society
alaces on reproductive/developmental
lealth, and the large number of fetal
osses experienced each year in the U.S.
nearly 1 million (Ventura et al. 2000)),
we believe it is important to provide
some quantitative indication of the
potential risk suggested by some of the
published results on reproductive/
developmental endpoints, despite the
absence of certainty regarding a causal
link between disinfection byproducts
and these risks. To do this, we have
adapted illustrative PAR calculations
from several studies on the relationship
between chlorinated water exposure and
fetal loss and applied these to national
statistics on annual incidence of fetal
loss.
Specifically, we calculate the
unadjusted population attributable risk
associated with each of the three
distinct population-based
epidemiological studies of feta! loss
published: Waller et al. 2001, King et al.
2000a, and Savitz et al. 1995. All three
are high quality studies that have
sufficient sample sizes and high
response rates, adjust for known
confounders 2, and have exposure
assessment information from water
treatment data, residential histories, and
THM measurements. Because the
populations in these three studies
appear to have TTHM exposures
significantly greater than those of the
general U.S. population, we have
chosen to scale the results using
Information Collection Rule data to
allow us to derive population
attributable risks that may be more
relevant to the general U.S. population
(USEPA 2003i).
These three studies (using unadjusted
data to allow for comparability, and
scaled to the TTHM levels reported in
the Information Collection Rule data
base) yield median PARs of 0.4%, 1.7%,
and 1.7% (with 95% confidence
intervals for each of the studies of 0 to
4%)3. Using the prevalence of fetal loss
reported by CDC, the median PARs for
these three studies suggest that the
incidence of fetal loss attributable to
exposure to chlorinated drinking water
could range from 3,900 to 16,700
annually. As part of the analysis to
evaluate potential reduction in fetal loss
for the Stage 2 DBPR, EPA assumed that
reductions in risk are proportional to
the 28 percent reductions in the number
of locations having one or more
quarterly TTHM measurements that
exceed the study population cut-offs
(>75 to >81 ug/1, depending on study).
This analysis implies that a range of
1,100 to 4,700 fetal losses could be
2 Use of unadjusted PAR estimates has the effect
of removing the adjustments for known
confounders, however, EPA helieves the unadjusted
estimates are adequate for purposes of the
illustrative calculations presented here.
:*The negative lower 95% confidence intervals for
all three studies was truncated at zero.
avoided per year as a result of the Stage
2 rule.
Caution is required in interpreting the
numbers because many experts
recommend that population attributable
risk-analysis should not be conducted
unless causality has been established.
Causality has not been established
between exposure to disinfection
byproducts and fetal loss. The estimates
presented here are not part of EPA's
quantitative benefits analysis, and the
ranges are not meant to suggest upper
and lower bounds. Rather, they are
intended to illustrate quantitatively the
potential risk implications of some of
the published results.
EPA has not monetized the value of
potential reductions in fetal loss, but
recognizes that there is a significant
value associated with improvements in
reproductive and developmental health.
In the absence of valuation studies
specific to the health endpoints of
concern, the Agency typically draws
upon existing studies of similar health
endpoints to estimate benefits. The
"transfer" of the results of these studies
to value similar health endpoints must
be done carefully and methodically,
controlling for differences in the health
endpoints and in the relevant
populations. Some researchers have
attempted to transfer values using
sophisticated analytical techniques such
as preference calibration methods (e.g..
Smith et al. 2002). Regardless of the
approach used, "benefit transfer"
requires systematic comparison of the
differences in the health effects in the
studies and those resulting from the
regulation. Application of benefit
transfer leads to a detailed qualitative
examination of the implications of using
those studies and potentially to
empirical adjustments to the results of
the existing studies.
The Agency is investigating further
work specific to the case of fetal loss
valuation. One possible area of further
research is the value that prospective
parents attach to reducing risks during
pregnancy. In this regard, the
substantial lifestyle changes that
prospective parents often undertake
during pregnancy suggests that reducing
these kinds of risks is of value. A second
possible area of further investigation
would be work on benefit transfer
methodologies that address how
existing studies can inform the
estimation of the benefits of reduced
fetal loss.
EPA has not monetized the potential
reductions in fetal loss. Without more
information and discussion on these
subjects the Agency cannot fully
consider and describe the implications
of relying upon existing studies.
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
However, research on valuation and
benefit transfer continues to progress
and the Agency anticipates new
research and future efforts to value
reproductive and developmental
endpoints.
EPA was also unable to quantify or
monetize the benefit from potential
reductions in other cancers, such as
colon and rectal, that may result from
this rule. Both toxicology and
epidemiology studies indicate that other
cancers may be associated with DBF
exposure but currently there is not
enough data to quantify or monetize
these cancer risks.
Other potential non-health related
benefits not quantified or monetized in
today's proposed rule include reduced
uncertainty about becoming ill from
consumption of DBFs in drinking water,
the ability for some treatment
technologies to eliminate or reduce
multiple contaminants, and monitoring
changes that will ensure that systems
can effectively measure their DBF levels
resulting in greater equity in protection
from DBFs. First, the reduced
uncertainty concept depends on several
factors including consumer's degree of
risk aversion, their perceptions about
drinking water quality (degreii to which
they will be affected by the regulatory
action), and the expected probability
and severity of human health effects
associated with DBFs in drinking water.
This effect could be positive or negative
depending on whether knowledge of the
rule decreases or increases their concern
about DBFs in drinking water and
potentially associated health effects.
Another nonqualified potential
benefit is the impact of technology
selection to address DBFs on a system's
ability to address other contaminants.
For example, membrane technology
(depending on pore size), can be used to
lower DBF formation but it can also
remove other contaminants that EPA is
in the process of regulating or
considering regulating. Therefore, by
installing membrane technology, a
system may not have to make new
capital improvement to comply with
future regulations.
Last, today's proposed rule makes
changes to Stage 1 monitoring
requirements. The IDSE monitoring
provision of the proposed Stage 2 DBPR
will help systems identify locations to
conduct their routine monitoring to
capture high DBF occurrence levels.
Also, the proposed Stage 2 DBPR will
prevent a system from conducting
sampling designed to avoid monitoring
when DBF formation is generally higher.
For example, the Stage 1 DBPR required
systems to take quarterly samples but
samples could conceivably be taken in
December (4th quarter) and January (1st
quarter) when the waters in the
distribution system are colder and DBP
formation generally lower. The
proposed Stage 2 DBPR addresses this
issue by requiring that the samples must
be taken about 90 days apart. The
benefits of these provisions include the
greater certainty that health protection
is actually achieved because it is more
likely that a system's high DBP levels
will be identified. In addition, the rule
will reduce variability in the DBP levels
throughout the distribution system,
ensuring greater equity in public health
protection.
2. Quantifiable Health Benefits
Although DBFs in drinking water
have been associated with non-
cancerous health effects discussed
previously, the quantified benefits that
result from today's rule are associated
only with estimated reductions in DBF-
related bladder cancer. A complete
discussion of risk assessment
methodology and assumptions can be
found in Chapter 5 of the Stage 2 DBPR
Economic Analysis (USEPA 2003i).
Section III of this preamble also
discusses the health effects that have
been associated with DBP exposure.
The annualized present value benefits
for reductions in bladder cancer that are
the result of today's rule for both
community water system (CWS) and
non-transient non-community water
systems (NTNCWSs) range from $0 to
$986 million using a three percent
discount rate ($0 to S854 million using
a seven percent discount rate). Overall,
the Stage 2 DBPR may reduce on
average 0 to 182 bladder cancer cases
per year.
The lower estimate of zero is included
because of inconsistent evidence
regarding the association between
exposure to DBFs and cancer. The upper
estimate of monetized benefits and cases
avoided is based on a population
attributable risk (PAR) of 17 percent.
Table VII-3 also presents monetized
benefits based on a PAR value of 2%.
The PAR estimates are derived from an
analysis of five epidemiological studies
which indicate that perhaps 2 to 17
percent of bladder cancers may be
attributable to DBP exposure. These
PAR estimates are described in more
detail in section III of today's document.
These are the same PAR values that EPA
used in the Stage 1 DBPR benefits
analysis, as discussed in the Regulatory
Impact Analysis for the Stage 1 DBPR
(USEPA 1998f). Table VII-3 shows the
estimated benefits associated with
bladder cancer reduction as a result of
the proposed rule. Table VII-4
summarizes the mean, median and
confidence intervals used to value
reductions in bladder cancer.
To calculate the total value of benefits
derived from reductions in bladder
cancer cases as a result of the Stage 2
DBPR, a stream of estimated monetary
benefits is calculated by combining the
annual cases avoided with valuation
inputs using Monte Carlo simulation.
Use of a Monte Carlo simulation allows
the characterization of uncertainty
around final modeling outputs based on
the uncertainty underlying the various
valuation inputs. The Stage 2 DBPR
benefits model uses distributions of
value of statistical life (VSL),
willingness-to-pay (WTP), and income
elasticity values to attribute monetary
values (with uncertainty bounds) to the
number of bladder cancer cases avoided.
Several of the inputs needed in the
benefit analysis, such as the VSL and
WTP estimates, are based on older
studies that were updated to current
dollar values. In addition, both the VSL
and WTP values are dependent on
income levels. Therefore, these values
also have to be adjusted for increases in
real income growth from when the
studies were conducted. The valuation
inputs and an explanation of the update
factors used to bring these values to
current price levels and discussed in the
following two sections.
Valuation inputs. In order to monetize
the benefit from the bladder cancer
fatalities, EPA applied a VSL estimate to
the cancer cases that result in mortality.
EPA assumed a 26 percent mortality rate
for bladder cancer (USEPA 1999d). The
Agency uses a distribution of VSL
values which are based on 26 wage-risk
studies. The mean VSL value from these
studies is $4,8 million in 1990 dollars.
The mean value reflects the best
estimate in the range of plausible values
reflected by the 26 studies. A more
detailed discussion of these studies and
the VSL estimate can be found in EPA's
Guidelines for Preparing Economic
Analyses (USEPA 2000b).
The VSL represents the value of
reducing the risk of a premature death.
This valuation, however, does not take
into account the medical costs
associated with the period of illness
(morbidity increment) leading up to a
death. In its review of the Arsenic Rule,
the Science Advisory Board (SAB)
suggested that the appropriate measure
to use in valuing the avoidance of the
morbidity increment is the medical cost
attributable to a cancer case (USEPA
2001e). Based on available medical data,
EPA estimates the medical costs for a
fatal bladder cancer case to be $93,927
at a 1996 price level (USEPA 1999d).
This medical cost value (updated to
2000 price levels) is applied as a point
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49631
jstimate to each fatal case of bladder
;ancer in the benefits model.
A review of the available literature
lid not reveal any studies that
specifically measured the WTP to avoid
•isks of contracting nonfatal cases of
iladder cancer. Instead, two alternates
re used, the WTP to avoid the risk of
:ontracting a case of curable lymph
ancer (lymphoma) and the WTP to
jvoid a case of chronic bronchitis. The
3AB suggested this approach in their
eview of the Arsenic Rule (USEPA
2001e). The median risk-risk trade-off
'or a curable case of lymphoma was
jquivalent to 58.3 percent of the risk
attributed to reducing the chances of
facing a sudden death and are derived
from the Magat et al. study (1996).
Therefore, the Agency applies the 58.3
percent to the VSL distribution to derive
a range of value for non-fatal cancers
with a mean WTP value of $2.8 million
($4.8 million * 58.3 percent) at a 1990
price level. The WTP for avoiding a case
of chronic bronchitis is based on the
same methodology used for the Stage 1
DBPR (see Stage 2 DBPR EA (USEPA
2003i) for a complete discussion). The
estimate is based on a lognormal
distribution that uses the risk-dollar
tradeoff estimate and has a mean of
$587,500, standard deviation of
$264,826, and a maximum value of $1.5
million at 1998 price values.
Update factors. All valuation
parameters must be updated to the same
price level so comparisons can be made
in real terms. Values for VSL, WTP, and
the morbidity increment used in the
model are updated based on adjustment
factors derived from Bureau of Labor
Statistics (BLS) consumer price index
(CPI) data so that each represents a year
2000 price level. Table VII-4
summarizes these updates.
Table VIM. VSL, WTP, and Morbidity Increment Price Level Updates
Valuation Parameter
Morbidity Increment
VSL
WTP - Non-Fatal Lymphoma
WTP - Chronic Bronchitis
Base
Year
1996
1990
1990
1998
Mean Value
in Base
Year
(Millions)
$ 0.1
$ 4.8
$ 2.8
$ 0.6
CPI Update
Factor
1.14
1.32
1.32
1.06
Values at Year 2000 Price Level
(Millions)
Mean
$ 0.1
$ 6.3
$ 3.7
$ 0.6
Median
N/A
$ 5.5
$ 3.2
$ 0.6
Lower
(5th %tile)
N/A
$ 1.0
$ 0.6
$ 0.3
Upper
(95th %tile)
N/A
$ 14.5
$ 8.5
$ 1.1
Notes: Morbidity increment value is presented as a point estimate.
Source: Economic Analysis (USEPA 20031) Exhibit 5.29
Although the price level {year 2000) is
leld constant throughout the benefits
node), projections of benefits in future
fears are subject to income elasticity
idjustments. Income elasticity
idjustments represent changes in
valuation in relation to changes in real
ncome. For fatal cancers, the Agency
ised a triangular distribution with a
;entral estimate of 0.40 (low end: 0.08;
ligh end:!.00) to represent the
mcertainty of the income elasticity
ralue. For non-fatal cancers, the Agency
ises a triangular distribution with a
;entra! estimate of 0.45 (low end: 0.25;
ligh end: 0.60). These distributions are
ised as assumptions in the Monte Carlo
iimulation to further characterize
mcertainty in benefits estimates.
In order to apply the income elasticity
'alues in the model, they are combined
vith projections of real income growth
)ver the time frame for analysis.
opulation and real gross domestic
)roduct (GDP) projections are combined
o calculate per-capita real GDP values.
\ more detailed discussion of these
idjustments is in Chapter 5 of the EA
USEPA 2003i).
The development of cancer due to
exposure to environmental carcinogens
involves a complex set of processes that
are not well-understood for most
specific substances. In general, however,
the development of cancer involves
some time period, usually referred to as
the latency period, between the initial
exposure and the manifestation of
disease. Defining a latency period is
highly uncertain because the mode of
action for most chemical contaminants
are poorly understood. Latency periods
in humans often involve many years,
even decades.
EPA recognizes that despite
uncertainties in the latency period
associated with different types of
carcinogens, it is unlikely that all cancer
reduction benefits would be realized
immediately upon exposure reduction.
If it is assumed that lower risk is
attained immediately upon reduction in
exposure, this would tend to
overestimate the benefits. On the other
hand, assuming that no risk reduction
occurs for some period of time following
exposure reduction may lead to an
underestimation of the benefits. There
will likely be some transition period as
individual risks become more reflective
of the new lower exposures than the
past higher exposures.
Recently, the Arsenic Rule Benefits
Review Panel of the EPA Science
Advisory Board (SAB) addressed this
issue in detail and provided some
guidance for computing benefits to
account for this transition period
between higher and lower steady-state
risks (USEPA 2003s). The Arsenic Rule
Benefits Review Panel coined the term
"cessation-lag" to emphasize the focus
on the timing of the attenuation of risk
after reduction in exposures to avoid
confusion with the more traditional
term of "latency" that reflects the
increased risk4 from the time of initial
exposure.
4 SAB included the following in its report on
arsenic to emphasize this difference; "An important
point is that tho lime to benefits from reducing
arsenic in drinking water may not equal the
estimated time since first exposure to an adverse
effect. A good example is cigarette smoking: the
latency between initiation of exposure and an
increase in lung cancer risk is approximately 20
years. However, after cessation of exposure, risk for
lung cancer begins to decline rather quickly. A
benefits analysis of smoking cessation programs
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Although the focus of the cessation
lag discussion in the SAB review was on
reducing levels of arsenic in drinking
water, much of their consideration of
this issue has more general applications
beyond just the arsenic issue at hand. In
particular, SAB noted the following:
• The same model should be used to
estimate the time pattern of exposure
and response as is used to estimate the
potency of the carcinogen.
• If possible, information about the
mechanism by which cancer occurs
should be used in estimating the
cessation lag (noting that late-stage
mechanisms in cancer formation imply
a shorter cessation lag than early stage
mechanisms).
• If specific data are not available for
characterizing the cessation lag, an
upper bound for benefits can be
provided based on the assumption of
immediately attaining steady-state
results.
• In the absence of specific cessation
lag data, other models should be
considered to examine the influence of
the lag.
Following the release of the SAB
report on arsenic, EPA initiated an effort
to explore approaches to including the
cessation lag in modeling risk reduction
and calculating benefits for the arsenic
regulation. EPA recognized, however,
that the concept of cessation lag is not
only applicable to arsenic but to other
drinking water contaminants having a
cancer end-point as well.
In response to the SAB cessation lag
recommendations, EPA has:
• Conducted a study using data on
lung cancer risk reductions following
cessation of smoking that resulted in the
January 2003 report Arsenic in Drinking
Water: Cessation Lag Model (USEPA
2003s).
• Conducted an expert scientific peer
review of that draft report.
• Initiated development of general
criteria for incorporating cessation lag
modeling in benefits analyses for other
drinking water regulations.
In the effort to develop a cessation lag
model specific to DBFs, EPA reviewed
the available epidemiological literature
for information relating to the timing of
exposure and response, but could not
identify any studies that were adequate,
alone or in combination, to support a
specific cessation lag model for DBFs in
drinking water. Thus, in keeping with
the SAB recommendation to consider
other models in the absence of specific
cessation lag information, EPA explored
the use of information on other
carcinogens that could be used as a
based on the observed latency would greatly
underestimate th9 actual benefits."
indicator to characterize the influence of
cessation lag in calculating benefits. The
carcinogen for which the most extensive
database was available for
characterizing cessation lag was for
cigarette smoking. EPA examined
several extensive epidemiological
studies on the comparison of the risks
of adverse health effects, including lung
cancer, for smokers and former smokers.
EPA selected the Hrubek and
McLaughlin (1997) study as the most
appropriate study for development of a
statistical model of disease response to
smoking cessation. This was a
comprehensive study involving a 26-
year follow-up of almost 300,000 U.S.
male military veterans. More detail
about this study and how it is applied
to estimate the cessation lag can be
found in Chapter 5 of the EA (USEPA
2003i) and the cessation lag document
(USEPA 2003s).
The smoking cessation lag data imply
that the majority of the potential steady
state cases avoided occur within the
first several years, but with diminishing
incremental increases in later years. For
exartple, the cessation lag model
indicates that approximately 40 percent
of the steady-state cases avoided are
achieved by the end of the second year,
with 70 percent achieved by the end of
the fifth year, and approximately 80
percent by the tenth year. By the
twentieth year, 90 percent of the steady
state cases are avoided.
EPA recognizes that there are several
factors that contribute to the uncertainty
in the application of the specific
cessation lag model used in the
estimation of the benefits of the
proposed Stage 2 regulation. A key
factor to consider in assessing this
impact is the likely mode of action of
DBFs in eliciting bladder cancer versus
the mode of action of tobacco smoke in
producing lung cancer, and in particular
whether they behave as initiators or
promoters of the carcinogenic process.
As discussed in the SAB report and the
EPA Cessation Lag report (USEPA
2001e, USEPA 2003s), carcinogens that
act solely or primarily as initiators
would tend to show a longer cessation
lag (lower rate of risk reduction
following reductions in exposure) than
carcinogens that act solely or primarily
as promoters. The available information
on tobacco smoke and lung cancer
suggests that it involves a mixture of
both initiators and promoters, and
therefore the cessation lag derived from
smoking data is expected to reflect the
combined influence of these divergent
mechanisms. There are no data available
on the mechanism of action for DBFs
and bladder cancer; indeed the specific
carcinogenic agent(s) present in
disinfected water responsible for the
observed effect have not been identified.
The use of the tobacco smoke cessation
lag model reflecting a mixture of
initiators and promoters would be
expected to attenuate a possible bias in
either direction if the DBFs responsible
for bladder cancer are acting
predominately as either initiators or
promoters.
Another factor to consider is that the
cessation lag model used is based upon
exposure to tobacco smoke where lung
cancer is the end-point but is being
applied to exposure to disinfection by-
products where the end-point is bladder
cancer. Of concern here is that there is
a more direct correlation between
inhalation and the site of cancer for
smoking than there is for ingestion and
inhalation of drinking water and the
sites of cancer for DBF exposure.
Unfortunately, EPA does not have data
on which to develop a cessation lag
model using data specific to how
changes in DBF exposures affect the
risks of developing bladder cancer.
Another divergence, and perhaps the
most important, between the smoking
model and the DBF application is that
the smoking model is based on complete
cessation of exposure, whereas in the
case of DBP exposure is only being
reduced, hi some water systems the
reduction is only 10 percent, whereas in
others it may be as high as 60 percent,
with an average of approximately 30%.
This moderate reduction in exposure
may prevent full DNA repair, which
some scientists interpret as the basis for
the short cessation lag associated with
smoking.
Currently, smoking is the only
contaminant for which enough data
exist to estimate a cessation lag. In the
absence of a reliable cessation lag model
based specifically on DBFs and bladder
cancer, EPA used the cessation lag
model based on smoking to provide a
means of estimating the rate at which
bladder cancer risk in the exposed
population falls from the pre-Stage 2
levels to the post-Stage 2 levels.
However, this model is derived from
data involving notable differences from
DBFs in drinking water, including
different cancer sites (lung versus
bladder), different exposure pathways
(inhalation versus a combination of
ingestion, inhalation and dermal),
different risk levels, and, perhaps most
importantly, complete cessation for
smoking versus small exposure
decreases for DBFs. For these reasons, ...
the extent to which the smoking / lung
cancer model is directly transferable to
DBP / bladder cancer is uncertain. It is
not possible to know, however, whether
and to what degree the tobacco smoke
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49633
cessation lag model either over-states or
under-states the rate at which
population risk reduction for bladder
cancer occurs following DBF exposure
reductions.
EPA is currently examining the
recently published meta-analysis by
Villanueva et al. (2003) to determine if
the information provided on increases
in risk as a function of duration of
exposure can provide any insight on
how reductions in risk over time might
occur following reductions in exposure.
Villanueva et al. (2003) demonstrated
that the risk associated with chlorinated
drinking water and bladder cancer are
related to exposure duration.
Specifically, they estimated a unit
increase in the odds ratio of 1.006 per
year (95% CI of 1.004 to 1.009). The
model suggests a cumulative odds ratio
of 1.13 after 20 years of exposure (95%
CI of 1.08 to 1.20), and 1.27 (95% CI of
1.17 to 1.43) after 40 years. This result
is consistent with most of the individual
studies which do not show statistically
significant risk increases until at least
30-40 years of exposure. However, these
studies provide indirect evidence only
about the latency of potential effects.
For perspective, it is important to note
that the latency between initiation of
exposure and an increase in lung cancer
risk is approximately 20 years. As noted
above, latency is not the same as the
cessation lag. EPA is requesting
comment on (a) the potential
application of the Villanueva et al.
(2003) model to estimate reductions in
bladder cancer risk that might
accompany decreased exposure to DBFs
as a result of the Stage 2 Rule; (b) the
advantages and disadvantages of using
the current approach—i.e., application
of the smoking cessation lag model; and
(c) suggestions for alternative data sets
or approaches to characterize cessation
lag.
In addition to the delay in reaching a
new steady-state level of risk reduction
as a result of cessation lag effects, there
is a delay in exposure reduction
resulting from the Stage 2 DBPR
implementation. In general, EPA
assumes that a fairly uniform increment
of systems will complete installation of
new treatment technologies each year,
with the last systems installing
treatment by 2013. EPA recognizes that
more systems may start in early or later
years, but believes that a uniform
schedule is a reasonable assumption.
Appendix D of the EA presents detailed
information regarding the rule activity
schedule assumptions (USEPA 2003i).
The delay in exposure reduction
resulting from the rule implementation
schedule is incorporated into the
benefits model by adjusting the
cessation lag weighting factor. For
example, if ten percent of systems
install treatment equipment (and start
realizing reductions in cancer cases) in
year one, only that portion of the cases
are modeled to begin the cessation lag
equilibrium process in that year. Thus,
the resulting "weighted weighting
factor" is higher relative to the base
factor. Appendix E in the EA (USEPA
2003i) presents detailed breakdowns of
all weighting factor adjustments and
resulting cancer cases avoided, by year,
for each rule alternative based on the
application of the cessation lag
methodology.
3. Benefit Sensitivity Analyses
The Agency performed one other
benefit sensitivity analysis which is
included in the EA to allow for
comparison with the benefit estimates
calculated for the Stage 1 DBPR. This
analysis assumes that there is not a
cessation lag or latency adjustment
associated with bladder cancer
reductions that result from the rule. In
this case, the analysis assumes that the
steady state reduction in bladder cancer
occurs immediately with rule
implementation. This is the same
methodology used to estimate the
quantified benefits of the Stage 1 DBPR.
D. Costs of the Proposed Stage 2 DBPR
In estimating the costs of today's
proposed rule, the Agency considered
impacts on water systems (CWSs and
NTNCWSs) and on States (including
territories and EPA .implementation in
non-primacy States). EPA assumed that
systems would be in compliance with
the Stage 1 DBPR, which has a
compliance date of January 2004 for
ground water systems and small surface
water systems and January 2002 for
large surface water systems. Therefore,
the cost estimate only considers the
additional requirements that are a direct
result of the Stage 2 DBPR. More
detailed information on cost estimates
are described later and a complete
discussion can be found in Chapter 6 of
the Stage 2 DBPR EA (USEPA 2003i)
1. National cost estimates
EPA estimates that the mean
annualized cost of the proposed rule
ranges from approximately $59.1
million using a three percent discount
rate to $64.6 million using a seven
percent discount rate. Drinking water
utilities will incur approximately 98
percent of the rule's costs. States will
incur the remaining rule cost. Tables
VII-5 a and b summarize the total
annualized cost estimates for the
proposed Stage 2 DBPR. In addition to
mean estimates of costs, the Agency
calculated 90 percent confidence
bounds by considering the uncertainty
around the mean unit technology costs.
Table VII-6 shows the undiscounted
capital cost and all one-time costs
broken out by rule component. A table
comparing total annualized costs among
the regulatory alternatives considered
by the Agency is located in subsection
VII.G.
BILLING CODE 6560-50-P
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
49637
I. Water system costs
The proposed Stage 2 DBPR applies to
ill community or nontransient
loncomrmmity water systems that add
i chemical disinfectant other than UV or
iistribute water that has been treated
vith a disinfectant other than UV. EPA
las estimated the cost impacts for both
ypes of public water systems. As shown
n Tables VI1-5 a and b, the total
innualized present value costs for CWSs
s approximately $55,8 million and for
sJTNCWSs, $2.2 million, using a three
jercent discount rate ($60.8 million and
J2.2 million using a seven percent
Hscount rate).
Although the number of systems
idding treatment is small, treatment
;osts make up a significant portion of
he total costs of the rule (more than 75
percent of total rule costs). Table VII-7
ihows the baseline number of plants
ind the estimated percent of those
jlants adding treatment. The estimated
percent of plants adding advanced
reatment or converting to chloramines
s 2.8 percent of all systems. A higher
jercentage of surface water plants are
predicted to add treatment compared to
>round water plants. However, the
baseline number of ground water plants
is larger than that of surface water
plants, so there is a larger number of
ground water plants adding treatment.
Subsection VII.F. provides a more
detailed explanation of treatment
changes that may occur as a result of the
proposed rule.
All systems will incur costs for rule
implementation. Some will need to
conduct a one-time Initial Distribution
System Evaluation (IDSE) and others (a
different subgroup depending on the
system size) may incur additional costs
for routine DBF monitoring. Some
systems may also have to conduct a
peak excursion evaluation if single
samples indicate high DBF levels.
Sixty-nine percent of surface water
and 7 percent of ground water CWSs are
predicted to conduct the IDSE
monitoring. EPA estimates that a very
small portion of systems (approximately
16 percent overall) will conduct
additional routine monitoring beyond
the Stage 1 DBPR requirements.
However, fewer samples overall would
be required if a population-based
approach is implemented instead of the
plant-based approach that is currently
being used to estimate monitoring costs.
Section V describes the population-
based approach in more detai! and a
discussion of how this approach may
influence costs is provided in Appendix
H of the EA (USEPA 2003i). A small
percentage of systems (approximately
3.0 percent of surface water CWSs and
0 percent of ground water systems) are
expected to experience significant
excursions.
A complete discussion of the rule
provisions is located in section V of this
preamble; the Stage 2 DBPR Economic
Analysis includes a complete analysis of
rule impacts (USEPA 2003i). Table VII-
8 summarizes the number of systems
subject to non-treatment related rule
activities. Column D indicates the
number of systems expected to use the
standard monitoring program to
implement the IDSE. Column F
indicates the number of systems
expected to increase monitoring sites
beyond that required by Stage 1. The
last two columns show the number and
percent of plants estimated to
experience significant excursions each
year.
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49638
Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
Table VH-7. Number of Plants Adding Treatment
System Size {Population
Served)
Stage 2 DBPR
Plant Baseline
Number and Percentage of Plants
Adding Treatment
Primarily Surface Water CWSs
<100
101-500
501-1,000
1,001-3,300
3,301-10,000
10,001-50,000
50,001-100,000
100,001-1 Million
> 1 Million
National Totals
470
799
505
1,103
1,213
1,287
538
572
74
6,560
21
26
17
41
45
75
31
33
4
293
4.4%
3.3%
3.3%
3.7%
3.7%
5.8%
5.8%
5.8%
5.8%
4.50/,
Primarily Ground Water CWSs
^100
101-500
501-1,000
1,001-3,300
3,301-10,000
10,001-50,000
50,001-100,000
100,001-1 Million
> 1 Million
National Totals
7,772
15,725
6,133
7,890
4,975
5,367
738
875
18
49,495
211
461
180
184
116
112
15
17
0
1,296
2.7%
2.9%
2.9%
2.3%
2.3%
2.1%
2.1%
1.9%
1.9%
2.6°/«
Primarily Suface Water NTNCWSs
<;100
101-500
501-1,000
1,001-3,300
3,301-10,000
10,001-50,000
50,001-100,000
100,001-1 Million
> 1 Million
National Totals
298
301
108
72
23
9
1
1
0
813
13
10
4
3
1
1
0
0
0
31
4.4%
3.3%
"" 3.3%
3.7%
3.7%
"5.8%
_ 5 8%
5.8%
0.0%
3.80/.
Primarily Ground Water NTNCWSs
^100
101-500
501-1,000
1,001-3,300
3,301-10,000
10,001-50,000
50,001-100,000
100,001-1 Million
> 1 IWIion
National Totals
Grand Total All Plants
3,662
2,624"
717
267
27
4
0
1
0
7,303
64,171
99
77
21
6
1
0
0
0
0
204
1,824
2.7%
2.9%
2.9%
2.3%
2.3%
2.1%
2.1%
1.9%
0.0%
2.8°X
2.8°/<
Source : Economic Analysis (USEPA 2003 i) Exhibit 6.16a, 6.16.b,6.17a, 6.17b
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
49639
Table VII-8 Number of Systems Subject to Non-Treatment Related Rule Activities
System Size
(Population Served)
Stage 2 DBPR
System
Baseline
A
Number and Percent of Systems Pert orrring Various Rule Activities
hpte mentation
B C=B/A*100
DSE Monitoring
D &=QfA*100
Additional Routine
Monitoring
F G=F/A*100
Significant
Excursion
Evaluations
H t=hVA*100
Surface Water and Mxed CWSs
< 100
101-500
501-1,000
1,001-3,300
3,301-10,000
10,001-50,000
50,001-100,000
100,001-1 Million
> 1 Million
National Totals
1,283
2,120
1,313
2,467
1,928
1,690
313
276
13
11.403
1,283 100%
2,120 100%
1,313 100%
2,467 100%
1,928 100%
1,690 100%
313 100%
276 100%
13 100%
11,403 100%
289.2 23%
546.4 26%
1,179.3 90%
2,215.8 90%
1,722.8 89%
1,454.0 86%
255.3 82%
213.3 77%
9.9 76%
7,886 69%
0.0 0%
42.5 2%
546.6 42%
1,027.0 42%
1,084.3 56%
0.0 0%
0.0 0%
0.0 0%
0.0 0%
2,700 24%
0.0 0%
2.0 0%
26-2 2%
49.3 2%
42.3 2%
133.2 8%
40.6 13%
41.1 15%
3.3 25%
338 3%
Ground Water Only CWSs
<100
101-500
501-1,000
1,001-3,300
3,301-10,000
10,001-50,000
50,001-100,000
100,001-1 Million
> 1 Milton
National Totals
7,601
11,836
4,089
4,869
2.288
1,232
129
60
2
32,105
7,601 100%
11,836 100%
4,089 100%
4,869 100%
2,288 100%
1,232 100%
129 100%
60 100%
2 100%
32,105 100%
236.2 3%
392.6 3%
482.0 12%
573.9 12%
270.5 12%
218.0 18%
22.8 18%
16.0 27%
1.0 50%
2,213 7%
0.0 0%
118.6 1%
1,691.9 41%
2,014.5 41%
946.6 41%
493.7 40%
51.6 40%
22.8 38%
0.9 44%
5,341 17%
0.0 0%
0.0 0%
0.0 0%
0.0 0%
0.0 0%
0.0 0%
0.0 0%
do 0%
0.0 0%
0 0%
Surface Water and Mxed NTNCWSs
<100
101-500
501-1,000
1,001-3,300
3,301-10,000
10,001-50,000
50,001-100,000
100,001-1 Mlton
> 1 Million
National Totals
303
302
109
74
22
9
1
1
0
821
303 100%
302 100%
109 100%
74 100%
22 100%
9 100%
1 100%
1 100%
0
821 100%
0.0. 0%
0.0 0%
0.0 0%
0.0 0%
0.0 0%
8.0 89%
1.0! 100%
1.0. 100%
0.0:
10 1%
0.0 0%
0.0 0%
0.0 0%
0.0 0%
6.0 27%
4.0 44%
1.0 100%
1.0 100%
0.0
12 1%
0.0 0%
0.0 0%
0.0 0%
0.0 0%
0.0 0%
0.0 0%
0.0 0%
0.0 0%
0.0
0 0%
Ground Water Only NTNCWSs
<100
101-500
501-1,000
1,001-3,300
3,301-10,000
10,001-50,000
50,001-100,000
100,001-1 Million
> 1 Million
National Totals
GRAND TOTAL
3,662
2,624
717
267
27
4
0
1
0
7,303
51,632
3,662 100%
2,624 100%
717 100%
267 100%
27 100%
4 100%
0 100%
1 100%
o;
7.303: 100%
51.632; 100%
0.0 0%
0.0 0%
0.0 : 0%
o.o : 0%
0.1 0%
0.9 19%
0.1; 19%
0.0 0%
0.0
1 0%
10,110 20%
0.0 0%
0.8 0%
5.1 1%
1.9 1%
0.3 1%
0.9 19%
0.1 19%
0.0 0%
0.0
9 0%
8,062 16%
0.0 0%
0.0 0%
0.0 0%
0.0 0%
0.0 0%
0.0 0%
0.0 0%
0.0 0%
0.0
0 0%
338 1%
Source: Economic Analysis (USEPA 2003i) Exhibit 6.3
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49640
Federal Register/Vol. 68, No, 159/Monday, August 18, 2003/Proposed Rules
In addition to using distributions to
develop unit cost estimates, the Agency
conducted sensitivity analyses to further
explore uncertainty regarding system
compliance estimates. The first two
sensitivity analyses were prepared to
evaluate the possibility that the IDSE
monitoring requirement will result in
more systems needing to install
treatment beyond what is predicted in
the current cost model (see chapter 7 of
the EA, USEPA 2003i, for details of this
analysis). Table VII-9 lists the high-end
estimates of the number of systems
adding treatment in IDSE sensitivity
analyses No. 1 and No. 2. For both IDSE
sensitivity analyses, only small
additional impacts were assumed
possible for systems serving 10,000
people or fewer because such systems
generally have much less complicated
distribution systems than larger
systems. EPA estimated that the mean
annualized costs at the 3% discount rate
could be as high as $77.5 million (IDSE
Sensitivity Analysis No. 1) or $108.8
million (IDSE Sensitivity Analysis No.
2) versus the Preferred Alternative
analysis estimate of $57.4 million. At
the 7% discount rate these estimates
would respectively correspond to $86.1
million, $120.7 million, and $63.3
million.
Table VII-9 Sensitivity Analysis on Potential Treatment Impacts of IDSE From Stage 1 to
Stage 2 (Community Water Systems)
SW< 10,000
SW> 10,000
GW < 10,000
GW> 10,000
Percent Adding Treatment
Preferred Alternative
3.7%
5.8%
2.7%
2.1%
IDSE No. 1
4.6%
9.9%
2.8%
3.2%
IDSE No. 2
4.8%
15.1%
2.9%
3.6%
Source: Economic Analysis, Exhibit?.! Chapter? (USEPA 2003i).
EPA believes that the percentage of
systems estimated to add treatment
under IDSE sensitivity analyses No. 1
and No. 2 are overestimates and that the
estimate for the Preferred Alternative is
likely to already capture the influence of
the IDSE because of the conservative
assumptions used in the analysis. For
example, the compliance forecast
analysis assumes that systems will try to
meet the LRAA MCLs with a 20%
margin of safety. Systems complying by
switching to chloramines may choose to
meet the new MCLs with a much
smaller margin of safety since
chloramines dampen the variability of
DBF concentrations within the
distribution system. Furthermore, EPA
believes that the number of ground
water and small surface water systems
adding chloramines or changing
technology in the baseline analysis may
be overestimated because their
monitoring requirements are expected to
be very similar from Stage 1 to Stage 2.
The Stage 1 DBPR required only one
compliance monitoring location (at the
point of maximum residence time) for
producing surface water systems serving
between 500 and 10,000 people and for
all ground water systems. The Stage 2
DBPR requires that these systems add an
additional site if they determine that
their high TTHM and high HAAS
concentrations do not occur at the same
location. If systems maintain a single
monitoring location for the Stage 2
DBPR, as many are expected to do,
calculation of compliance will produce
the same results for the running annual
average (RAA) and locational running
annual average (LRAA) measure,
implying that they are not likely to add
treatment for the Stage 2 DBPR if they
comply with the Stage 1 DBPR.
EPA conducted a third sensitivity
analysis to evaluate the possibility that
small systems will continue to monitor
at one point in their distribution system.
In this sensitivity analysis, EPA
assumed that no surface water plants
serving fewer than 10,000 people and no
ground water plants would add
treatment to meet Stage 2 DBPR
requirements (i.e., only costs are
associated for large surface water
systems). Under this analysis, the
average cost figures are reduced
dramatically from $57.4 million or $63.3
million to $22.9 million or $25.7 million
using a 3 percent or 7 percent discount
rate, respectively, for the Preferred
Regulatory Alternative. Chapter 7 of the
Economic Analysis (USEPA 2003i)
contains a detailed explanation of the
aforementioned sensitivity analysis.
3. State Costs
The Agency estimates that the States
and primacy agencies will incur an
annualized present value cost of $1.1
million to $1.5 million (using a three
percent and seven percent discount rate,
respectively). In order to estimate the
cost impact to States, EPA considered
initial implementation costs, costs for
assisting systems in evaluating IDSE
information, and for annual rule
implementation activities. EPA
considered the incremental change in
activities that result from the Stage 2
DBPR. For example, States may have to
update their databases to track the new
Stage 2 DBPR monitoring strategy but
could modify the system they developed
for the Stage 1 DBPR. EPA accounted for
the cost of a Stage 1 DBPR database in
the Stage 1 Regulatory Impact Analysis
{USEPA 1998f). State costs are not
expected to change dramatically
between alternatives.
4. Non-quantifiable
EPA has identified and quantified
costs that it believes are likely to be
significant. In some instances, EPA did
not include a potential cost element
because it believes the effects are
relatively minor and difficult to
estimate. For example, the Stage 2 DBPR
may be the determining factor in the
decision by some small water systems to
merge with neighboring systems. Such
changes have both costs (legal fees and
connecting infrastructure) and benefits
(economies of scale). Likewise, costs for
procuring a new source of water would
have costs for new infrastructure but
could result in lower treatment costs.
Also, EPA was unable to quantify
several distribution system-related
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
49641
changes that can reduce TTHM and
HAA5 levels. Activities such as looping
distribution systems and optimizing
storage can minimize retention times
and help to control DBF formation.
Costs for these activities range from
almost zero (modifying retention time)
to more substantial costs for modifying
distribution systems. In the absence of
detailed information needed to make
st evaluations for situations such as
:hese, EPA has included a discussion of
possible effects where appropriate.
E. Expected System Treatment Changes
In order to quantify the effects of the
Stage 2 DBPR, it is necessary to predict
low plants will modify their treatment
processes to meet the proposed
'equirements. To estimate the
incremental impacts of the Stage 2
DBPR, relative to the Stage 1 DBPR, EPA
:ompared predicted "ending
.echnologies" (types of treatment in use
ifter implementation of the Stage 2
DBPR) to the distribution of baseline
echnologies predicted to be in place
ifterthe implementation of the Stage 1
DBPR. This subsection outlines the
>rocess for deriving baseline and ending
Stage 2 technology distributions that are
he basis for the national cost estimates
)f today's proposed rule.
L. Pre-Stage 2 DBPR Baseline Conditions
Development of the Pre-Stage 2
)aseline (i.e., conditions following the
stage 1 DBPR) consists of the following
jrocesses:
• Compiling an industry profile—
dentifying and collecting information
in the segment(s) of the water supply
ndustry subject to the Stage 2 DBPR;
• Characterizing influent water
niality—summarizing the relevant
:haracteristics of the raw water treated
>y the industry; and
• Characterizing treatment for the
Jtage 1 DBPR—predicting what the
ndustry will do to comply with the
>rovisions of the Stage 1 DBPR.
Section IV of this document details
he data sources EPA used to
characterize water quality and treatment
practices for the nation's public water
systems. EPA also used information in
the Water Industry Baseline Handbook
(USEPA 2000J) to develop the industry
profile. The Baseline Handbook uses
data derived from the 1995 Community
Water Systems Survey and the Safe
Drinking Water Information System to
characterize the U.S. drinking water
systems. Another EPA study,
Geometries and Characteristics of Water
Systems Report (USEPA 2000k), also
provided information for the industry
profile.
EPA developed and used a model
(SWAT) to characterize treatment
following the Stage 1 DBPR and Stage 2
DBPR options considered. SWAT served
as the primary tool to predict changes in
treatment and DBF occurrence. The
model used a series of algorithms and
decision rules to predict the type of
treatment a large surface water plant
will use given a specific regulatory
alternative and source water quality.
Other tools were used to estimate
practices at large ground water systems
or any medium or small systems. A
Delphi process (a detailed technical
treatment characterization and DBF
occurrence review by drinking water
experts) was used to predict treatment
changes for large ground water systems
(those serving 10,000 or more people).
The results of the SWAT analyses and
the Delphi process were extrapolated to
the medium surface water and ground
water systems based on analysis of
source water treatment characteristics
and treatment decision trees. For the
small surface and ground water systems
analyses, a group of experts provided
predictions for a pre-Stage 2 baseline
and resulting treatment and water
quality conditions under the Stage 2
DBPR regulatory alternatives. A detailed
description of these analyses can be
found in the Economic Analysis for the
Stage 2 DBPR (USEPA 2003i).
2. Predicted Technology Distributions
Post-Stage 2 DBPR
The treatment compliance forecast for
the Stage 2 DBPR has two components—
1} the percent of plants that must add
treatment to comply with Stage 2 DBPR
requirements, and 2) the treatment
technologies these plants are predicted
to select. This information, coupled
with the baseline data discussed before,
provides an estimate of the total number
of plants using specific technologies to
meet the requirements of the proposed
Stage 2 DBPR. National costs are then
generated using technology unit cost
information.
The four step process EPA used to
develop a Stage 2 DBPR compliance
forecast is summarized in table VII-10.
The difference between the Stage 1
DBPR Technology Selections and Stage
2 DBPR Technology Selections (Step 4—
Incremental Technology Selections) was
used to develop national cost estimates
for today's proposed rule. Tables VII—11
a and b (surface water) and VII—12 a and
b (ground water) show the incremental
technology selections shown as the
percent change between Stage 1 and
Stage 2 DBF rules.
TABLE VII-10.—STAGE 2 DBPR
COMPLIANCE FORECAST SUMMARY
Step
Description of Step
Model a pre-Stage 1 baseline sce-
nario using Information Collection
Rule data to allow consistent com-
parison between different rule al-
ternatives.
Model technology selection to meet
Stage 1 DBPR requirements
(Stage 1 DBPR Technology Selec-
tion).
Model technology selection to meet
Stage 2 DBPR requirements
(Stage 2 DBPR Technology Selec-
tion).
Subtract the results in Step 2 from
Step 3 and adjust to obtain the in-
cremental impact of an alternative
(Stage 2 DBPR incremental tech-
nology selection).
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49642
Federal Register/VoI. 68, No. 159/Monday, August 18, 2003/Proposed Rules
Table VH-lla. Technology Usage for CWS Surface Water Plants - Percent Change
From Stage 1 to Stage 2 Compliance
System Size
(Population Sened)
£100
101-500
501-1.000
1.001-3,300
3,301-10.000
10.001-50.000
50,001-100.000
100,001-1 Million
> 1 Million
Total %, Plants
Converting to
CLMOnly
A
0.8%; A
2.1%! 17
: 11
2.5%; 27
: 30
3.6%' 46
19
3.6% 21
: 3
2.7% 178
Advanced Technologies
Chlorine
Dioxide
B
$jg;iJ4j;;£,«-!K
0.0% i 0
; o
0.0% j 0
; 0
0.4%. 5
2
0.4%; 2
"6
0.1% 9
uv
c
3.1% 14
0.4% 3
: 2
0.5% 5
: e
0.7% B
4
0.7% 4
; 1
07%' 49
Ozone
D
0.0% 0
0
0.0% 0
0
0.0% 0
0
0.0% 0
"d
0.0%. 0
MF/UF
E
0.0% 0
0.0% 0
; b
0.0% 0
6
0.0%. 0
: o
0.0%, D
o
0-0% 0
GAC10
F
•^^t^lV^T?^
0.0%; Q
: 0
0.0%; 0
"\ 0
0.0%; o
GAC1D +
Ad\enced
Disinfectants
G
ffi fj f."/,!.txi1f~it~
0.7%; 9
4
0.7%' 4
i ' i
0 3% 18
GAC20
H
0.0%' C
0.0%: 0
:" o
0.0% • 0
'• 0
0.4%: 5
; 2
0.4%! 2
i 0
0.1% g
GAC20 +
Advanced
Disinfectants
I
0.6%i 3
0.7% B
'; 4
0.7%; s
- B
0.0%' 0
; 0
0.0% 0
., .....
0.4%; 29
Membranes
J
0.0%
0.0%
0.0%
0.0%
II
0
'6
0
d
0
b
0.0%
0.0%
0
6
0
Total
Convening
toCLM
- K
3.0% 14
3.6%> 29
18
4.0%: 45
•""49
5.1%i 66
: 28
5.1%, 29
a
4.3% 282
Total Adding
Technology
L = SUM(A:J)
4.4%. 21
3.3% 26
17
3.7%. 41
" ' " "45
5.8% 75
• 31
5.8%; 33
4
4.5%: 293
Note: Detail may not add due to independent rounding (some plant results are rounded to zero if less than 0.5 plants).
Source : Economic Analysis {USEPA 2003J) Exhibit 6.14a
Table VH-llb.
Technology Usage for NTNCWS Surface Water Plants - Percent
Change From Stage 1 to Stage 2 Compliance
System Size
(Population Served)
ilOO
101-500
501-t.OOO
1,001-3,300
3.301-10,000
10,001-50,000
50.001-100,000
100.001-1 Million
> 1 Million
Total %, Plants
Com*rtJng lo
CLMOnly
A
0.8% i 2
2.1%j 6
; 2
2.5% 2
... ....
3.6%: 0
' 0
3.6%! 0
0
1.7% 14
Advanced Technologies
Chlorine
Dioxide
B
vw^Si-i; I.K--
0.0%! o
; 0
0.0%- 0
: "6
o.4%; o
! °
0.4% i 0
: 0
0.0%: o
uv
c
3.1%: 9
0.4%' 1
0
0.5%: 0
; o
0.7% : 0
: 0
0.7% 0
0
1.4%. 11
Ozone
D
,., ,
0.0%; o
f"6
0.0%! 0
Total
Converting
loCLM
K
3.0%: E
3.6% 11
" "4
4.0%; 3
""""• \
5.1%; 0
; 0
5,1%: o
I 0
35%: 28
Total Adding
Technology
L - SUM(A.J)
4.4% I 13
3.3% 10
4
3.7%; 3
;• "1
5.8% 1
0
5.8% 0
0
3 8%: 31
Note: Detail may not add due to independent rounding (some plant results are rounded to zero if less than 0.5
plants).
Source : Economic Analysis (USEPA 2003i) Exhibit 6.14b
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
49643
Table VH-12a.
Technology Usage for Disinfecting CWS Ground Water Plants
Percent Change From Stage 1 to Stage 2 Compliance
System Size
(Population
Sei\ed)
£100
101-500
501-1,000
1,001-3.300
3,301-10.000
10.001-50.000
solodi-ioD.dbo
100.001-1 Million
> i' Million
Total %, Plants
CLMOnly
A '
1,0%' 8C
1.3%= 210
; 82
1.0% 7E
50
1.4%: 76
••-: i(j
1.3%: 11
;' ' D
1.21%' 599
UVCL2
B
0.0%. C
0.0% • 0
6
0.0%. 0
: 0
UVCLM
C
1.3%; 9B
1.4%: 225
1 88
1.3% i 102
J 64
0.00% s 0
.1.17%: 578
Ozone CL2
D
0-0%; 0
0.0% : 0
6
0.0% 0
0
0.1% 3
6
0.1% 0
5
0.01% 4
Ozone CLM
£
0.0%. 0
0.0% i 0
' " \ 0
0.0%. 0
• " '""6
0.2%, 12
2
0.2% 2
0
0.03%- 15
GAC20CL2
F
0.4% 33
02% 25
10
0.0% 0
b
0.0% 0
6
0.0% 0
0
0.14%; 68
GAC20CLM
G
0.0% 0
0.0% 0
'i 0
0.0% : 3
2
0.2%. 8
1
0.1%. 1
0
0.03%; 16
embranes CU
H
0.0% • 0
0.0%. 0
; 6
0.0% 0
L o
0.0%! 2
i - 6
0.0% i 0
• 6
0.00%; 2
Membranes CLfc
I
00%: o
0.0% 0
0
00%' 0
: 0
0.2%' 11
; 2
0.2%: 2
; 0
0.03%i ' 15
Total Coroeiting
to CLM
J - A+C+E+G-H
2,3%' 178
2,8%' 436
! 170
2.3%; 184
116
2.0%; 108
: 15
1.9%; 16
0
2.5%- 1.223
Total Adding
Technology
K = SUM(A:t)
2-7%- 211
2.9%: 461
180
2.3% 184
116
2.1% 112
15
1.9% 17
0
2.6% 1,296
Note: Detail may not add due to independent rounding (some plant results are rounded to zero if less than 0.5 plants).
Source: Economic Analysis (USEPA 2003J) Exhibit 6.l6a
Table VIM2b.
Technology Usage for Disinfecting NTNCWS Ground Water Plants -
Percent Change from Stage 1 to Stage 2 Compliance
System Size
(Population
Sened)
$100
101-500
501-1,000
1,001-3,300
3;3oi:i6,ooo
10.001-50,000
50,001-100,000
100,001-1 Million
> 1 Million
Total %. Plants
CLMOnly
A
10%- 38
1.3%. 35
; ' '10
1.0%; 3
., .. ^
1.4%, 0
i 0
1.3%: 0
! 0
1.17%= 65
UVCL2
B
0.0%' 0
0.0%: o
: o'
0.0%' 0
; -. ..
M^ff^P^i?
UVCLM
C
1.3%: 46
1.4%' 38
'"" io
1.3%: 3
{ o
0.00%' 0
1.34%: 98
Ozone CL2
D
0.0%. 0
0.0%; o
0
0.0%; 0
: " 6
0.1% : 0
0
0.1%: 0
0
0.00%: o
Ozone CLM
E
0.0%; o
0.0% 0
0
0.0% 0
0
0.2% 0
d
0.2% 0
0
0,00% 0
GAC20 Cl 2
. F
0.4% 15
0.2%; 4
: 1
0.0% : o
: o
0.0%: o
I 0
0.0% ; 0
; o
0.28% , 21
GAC20CLM
G
0.0%: o
0.0%.' 0
; o
0.0% i 0
0
0.2% 0
: o
0,1%' 0
0
0.00% . 0
embranes CL
H
0.0% 0
0.0% : 0
0
0-0%; o
; 6
0.0%! 0
1 o
0.0%} o
0
0.00% . 0
Membranes CLM
1
0.0% 0
D.0% 0
0
0.0% 0
6
0.2% 0
6
0.2% 0
0
Total Coo^rting
to CLM
J = A+C-tE+G+l
2.3%- &4
2.8% : 73
: 20
2.3%: 6
: 1
2.0%; 0
: 0
1.9%: 0
. i 0
2.5%: 183
Total Adding
Technology
K=SUM(A:I)
2.7%, 99
2.9% : 77
: 21
2.3% [ 6
1
2.1%; o
0
1.9%; o
i 0
2.8%: 204
Note: Detail may not add due to independent rounding (some plant results are rounded to zero if fess than 0.5 plants).
Source : Economic Analysis (USEPA 20031) Exhibit 6.16b
F. Estimated Household Costs of the
Proposed Rule
This analysis considers the potential
increase in a household's water bill if a
system passed the entire cost increase
resulting from this rule on to their
ustomers. It is a tool to gauge potential
impacts and should not be construed as
precise estimates of potential changes to
individual water bills.
Overall, the potential increase in
mean annual water bill per household is
estimated to be $8.38 for those systems
that need to install technology to
comply with this rule. Table VII-13
shows the range of household costs for
all surface and ground water systems
subject to the rule and also only for
those systems installing technology to
comply with this rule. For all systems,
including those that may not have to
take any additional action to comply
with this rule but are still subject to its
provisions, the mean annual household
cost is $0.51. The last two columns of
Table VII-13 show the potential impact
as the percent of households that will
incur either less than a $1 or less than
a $10 increase in their monthly water
bills (shown in the table as annual
values). For systems adding treatment,
84% of households will face less than
a $1 increase in their monthly bill,
while 99% are expected to face less than
a $10 increase.
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
Table VII-13. Potential Annual Household Cost Impacts
All Systems
All Small System:
SW 5 10,000
SW > 10,000
GW £ 10,000
GW > 10,000
All Systems
All Small System;
SW <; 10,000
SW > 10,000
GW <, 10,000
GW > 10,000
All Households Subject to the Stage 2 DBPR
Total Number of
Households Served
(Percent of Total)
98,254,000 (100.0%)
14,522,000 (100.0%)
3,165,000(3,2%)
58,876,000 (59.9%)
11,357,000(11.6%)
24,857,000 (25.3%)
Mean Annual
Household
Cost Increase
$0.51
$1.66
$3.7^
$0.34J
$1.08
$0.23
Median
Annual
Household
Cost Increase
$0.02
$0.18
$0.90
$0.00
$0.11
$0.01
90th Percentile
Annual
Household
Cost Increase
$0.47
$0.90
$2.96
$0.32
$0.53
$0.47
95th Percentile
Annual
Household
Cost Increase
$0.79
$2.96
$5.51
$0.33^
$1.37
$0.47
Percentage of
Annual
Household
Cost Increase
<$12
99.24%
98.23%
97.89%
99.35%
98.37%
99.57%
Percentage of
Annual
Household Cost
Increase < $120
99.96%
99.74%
99.09%
100.00%
99.92%
100.00%
Households Served by Plants Adding Treatment
Number of
Households Served
(Percent of Total)
4,793,000 (4.9%)
422,000 (2.9%)
142,000 (4.5%)
3,868,000 (6.6%)
279,000 (2.5%)
504,000 (2.0%)
Mean Annual
Household
Cost Increase
$8.52
$43.78
$60.64
$5.02
$35.18
$5.90
Median
Annual
Household
Cost increase
$1.22
$19.05
$9.08
$1.02
$19.22
$1.33
901h PercentHe
Annual
Household
Cost Increase
$20.57
$117.68
$166.67
$11.58
$72.07
$26.33
95th Percentile
. Annual
Household
Cost Increase
$33.98
$166.67
$270.04
$23.56
$117.68
$33.24
Percentage of
Household
Cost Increase
<$12
84.47%
39.38%
54.36%
90.16%
33.71%
78.73%
Percentage of
Household Cost
Increase < $120
99.18%
91.12%
79.78%
99.96%
96.94%
100.00%
Note: Detail may not to total add due to independent rounding. The last two columns show the % change as < $1 or <
$10 increase in monthly water bills
Source : Economic Analysis (USEPA 2003i) Exhibit 6.20
Both household cost estimates reflect
costs for rule implementation (e.g.,
reading and understanding the rule),
IDSE, additional routine monitoring,
and treatment changes. Although
implementation and the IDSE represent
relatively small, one-time costs, they
have been annualized and included in
the analysis to provide a complete
picture of household costs.
Overall, EPA estimates that 99 percent
of the 98 million households that are
provided disinfected drinking water
would face less than $1 increase in their
monthly water bill. Approximately 86
percent of the households impacted by
the rule are served by systems serving
at least 10,000 people; these systems
experience the lowest increases in costs
due to significant economies of scale.
Households served by small systems
that install advanced technologies will
face the greatest increases in annual
costs. The cumulative distributions of
household costs for all systems are
presented in the Economic Analysis
(USEPA 2003i).
When interpreting the results of the
household cost analysis, it is important
to remember that systems, especially
small systems, may have other options
that were not included in the
compliance forecast. For example, the
system may identify another water
source that may form lower levels of
TTHM and HAAS. Systems that can
identify such an alternate water source
may not have to treat that water as much
as their current source, resulting in
lower treatment costs that may offset the
costs of obtaining water from the
alternate source. Systems may also be
able to connect to a neighboring water
system. While connecting to another
system may not be feasible for some
remote systems, EPA estimates that
more than 22 percent of all small water
systems are located within metropolitan
regions (USEPA 2000c) where distances
between potential connecting water
systems may not present a prohibitive
barrier. Consolidation was not an
element used in developing the
compliance forecasts for small systems.
Costs for consolidation may be either
greater or less than the costs for
changing technologies, and
consolidation may have other benefits
(e.g., lower costs for compliance with
future regulations). In addition,
potentially lower cost alternatives such
as controlling water residence time in
the distribution systems were not
included in the compliance forecast.
Also, more small systems than
projected in the primary analysis may
already be in compliance with Stage 2
DBPR. A sensitivity analysis discussed
in the subsection VII.D.2 describes this
issue in more detail. Also, certain
technologies installed to treat DBFs may
treat many other contaminants thus
eliminating the need to install
additional equipment to comply with
future drinking water regulations.
G. Incremental Costs and Benefits of the
Proposed Stage 2 DBPR
Incremental costs and benefits are
those that are incurred or realized in
reducing DBF exposures from one
alternative to the next more stringent
alternative. Estimates of incremental
costs and benefits are useful in
considering the economic efficiency of
different regulatory options considered
by the Agency. However, as pointed out
by the Environmental Economics
Advisory Committee of the Science
Advisory Board, efficiency is not the
only appropriate criterion for social
decision making (USEPA 2000n).
Generally, the goal of an incremental
analysis is to identify the regulatory
option where net social benefits are
maximized. If net incremental benefits
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49645
re positive, society is incurring greater
osts as a result of the health damages
ompared to the costs society could pay
3 reduce those health damages (i.e.
ociety would be better off to invest
sore in controlling the health damage).
F net incremental benefits are negative,
ian the cost of the additional control is
.igherthan the value of the additional
ealth damages avoided. Therefore, the
efficient" regulatory level is where the
ext additional incremental reduction
i health damages equals the
incremental cost of achieving that
reduction. However, the usefulness of
this analysis is constrained when major
benefits and/or costs are unqualified or
not monetized.
For the proposed Stage 2 DBPR,
presentation of incremental quantitative
benefit and cost comparisons may be
unrepresentative of the true net benefits
of the rule because a significant portion
of the rule's potential benefits are non-
quantifiable (see section C.I). Tables
VII-14 and VII-15 show the total
estimated costs and benefits for each
alternative. Evaluation of the
incremental changes between different
rows in the tables shows that
incremental costs generally fall within
the range of incremental benefits for
each more stringent alternative. Equally
important, the addition of any benefits
attributable to the non-quantified
categories would add to the benefits
without any increase in costs.
TABLE Vll-14.—TOTAL ANNUALIZED PRESENT VALUE COSTS BY RULE ALTERNATIVE
(Smilltons, 2000$)
Rule alternative
It. 1
It. 2
It. 3
Total annuallzed cost ($miltions)
3 Percent discount rate
Mean estimate
$59.1
182.2
409.6
594.3
90 Percent confidence bound
Lower (5th %
tile)
$54.3
165.1
383.6
556.3
Upper (95th %
tile)
$63.9
199.6
435.7
631.9
7 Percent discount rate
Mean estimate
$64.6
195.1
442.7
644.2
90 Percent confidence bound
Lower (5th %
tile)
$59.2
175.9
413.4
601.1
Upper (95th %
tile)
$70.0
214.3
472.2
686.9
Note: Costs represent values in millions of 2000 dollars. Estimates are discounted to 2003—90 percent Confidence Intervals reflect uncertainty
i technology unit cost estimates
Source: Economic Analysis (USEPA 2003i) exhibit 6.24
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Table VIMS. Total Annualized Present Value Benefits by Rule Alternative (Smillions, 2000$)
Discount Rate,
WTP for Non-
Fatal Cases
Preferred
Alternative
Alternative
1
Alternative
2
Alternative
3
Number and Value of Estimated Bladder Cancer Cases Avoided1
Causality has not been established; however, the weight of evidence supports PAR estimates of potential benefits.
Zero is within the range of potential benefits, but evidence indicates that both the number of cases and the value of
preventing those cases could be significant (see below).
2% PAR
Average Annual
Number of Cases
Avoided
Annualized
Benefits of Cases
Avoided
(90% Confidence
Bounds)2
3 %, Lymphoma
7 % Lymphoma
3 % Bronchitis
7 % Bronchitis
21
$113
($18-258)
$98
($16-224)
$55
($13-120)
$48
($11-104)
22
$117
($19-268)
$102
($16 - 232)
$57
(13-124)
$49
($11 -108)
135
$773
($116-1,675)
$636
($101 -$1,452)
$356
($81 - 776)
$309
{$71 - 673)
161
$873
($139-1,995)
$757
($120-1,730)
$424
($97 - 924)
$368
($84 - 802)
17% PAR Value
Average Number
of Cases Avoided
Annualized
Benefits of Cases
Avoided
90% Confidence
Bounds)2
3 %, Lymphoma
7 % Lymphoma
3 % Bronchitis
7 % Bronchitis
182
$986
($157-2,253)
$854
($136-1,952)
$479
($109-1,044)
$415
($95 - 905)
189
$1,024
($163-2,340)
$887
($141 - 2,027)
$498
($114-1,084)
$431
($99 - 940)
1,182
$6,398
($1,016-14,619)
$5,546
($881 - 12,672)
$3,109
($709-6,771)
$2,697
($616-5,871)
1,408
$7,621
($1,211-17,415)
$6,607
($1,050-15,097)
$3,704
($845 - 8,066)
$3213
($734 - 6,995)
Adverse Reproductive and Developmental Health Effects Avoided
Causality has not been established, and numbers and types of cases avoided, as well as the value of such cases,
were not quantified in the primary benefits analysts. Given the numbers of women of child bearing age exposed (58
million), the evidence indicates that the number of cases and the value of preventing those cases could be
significant. See results of the illustrative calculation in VII.C.1 .
Other Health Benefits
Qualitative assessment indicates that the value of other health benefits could be positive and significant.
Non-Health Benefits
Qualitative assessment indicates that the value of non-health benefits could be positive.
1. Based on TTHM as indicator. EPA recognizes that the lower bound eslimate may be as low as zero since causality
has not yet been established between exposure to chlorinated water and bladder cancer.
2. The 90 percent confidence bounds shown in the exhibit reflect uncertainty in the VSL, WTP, and income elasticity
adjustment.
Source: Economic Analysis (USEPA 2003i) exhibit 5.28
The range of quantified benefits 2 and 3. However, the associated costs presented in Table VII-14 show values
increases significantly with Alternatives also increase significantly—cost figures approaching or exceeding $500 million
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49647
per year. Although the estimated
benefits for Alternatives 2 and 3 are
potentially significant, EPA rejected
these alternatives because the Agency
believes that the uncertainty about the
health effects data does not warrant the
additional expense associated with
these regulatory alternatives.
Given the uncertainty in the health
effects, and the resulting rejection of
Alternatives 2 and 3, a comparison of
Alternative 1 with the Preferred
Alternative shows that Alternative 1
would have approximately the same
benefits as the Preferred Alternative but
with greater costs. This results from the
inability of the Agency to estimate the
additional benefits of reducing the
bromate MCL. Alternative 1 was also
determined to be unacceptable due to
the potential for increased risk of
microbial exposure. See section VILA of
today's action for a description of
regulatory alternatives.
H, Benefits From the Reduction of Co-
Occurring Contaminants
Installing certain technologies to
control DBFs also has the added benefit
of controlling other drinking water
contaminants. For example, some
membrane technologies (depending on
pore size) installed to reduce DBF
precursors can also reduce or eliminate
many other drinking water
contaminants, including arsenic and
microbial pathogens. EPA has finalized
a rule to further control arsenic level in
drinking water and has proposed the
Ground Water Rule to address microbial
contamination. The Stage 2 DBPR is also
being concurrently proposed with the
Long Term 2 Enhanced Surface Water
Treatment Rule. Because of the
difficulties in establishing which
systems would have multiple problems
such as microbial contamination,
arsenic, and DBFs (or any combination
of the three), no estimate was made of
the potential cost savings from
addressing more than one contaminant
simultaneously.
/. Are There Increased Risks From Other
Contaminants?
Today's proposed rule may slightly
shift the distribution of TTHM and
HAAs to brominated species. Some
systems, depending on bromide and
organic precursor levels in the source
water and technology selection, may
experience a shift to higher ratios or
concentrations of brominated DBFs
while the overall TTHM or HAAS
concentration decreases. However, EPA
anticipates that this phenomenon may
only occur in a small percentage of
systems affected. For most systems,
overall levels of DBFs, as well as
brominated DBF species, should
decrease as a result of this rule.
EPA's analysis shows that a large
portion of systems that do not currently
meet Stage 2 requirements will do so by
switching from chlorination to
chloramination; approximately 5% of
surface water plants and 1.3% of ground
water plants in systems serving greater
than 10,000 are estimated to convert to
chloramination in order to comply with
the Stage 2 DBPR from the Stage 1 DBPR
(USEPA 2003J). A potential
chloramination byproduct is N-
nitrosodimethylamine (NDMA), a
probable human carcinogen. The
concern over the formation of NDMA in
the treatment process is based on the
compound's ability to persist for a long
period of time in the distribution
system. The mechanism of formation of
NDMA, however, is still under
examination. A number of ongoing
studies will also evaluate occurrence,
factors that affect NDMA formation,
mechanisms, treatment effectiveness
and improved analytical methods for
measuring NDMA.
Another contaminant of concern to
the Agency is chlorite. Levels may
increase slightly because of technology
shifts to chlorine dioxide resulting from
this rule but very few systems (<0.1
percent) are predicted to install this
technology. However, individual
systems will not shift to chlorine
dioxide unless they can meet the
chlorite MCL (established under the
Stage 1 DBPR) which is considered
protective of public health.
EPA also considered the impact this
rule may have on microbial
contamination that may result from
altering disinfection practices. To
address this concern, the Agency
developed this rule jointly with the
Long Term 2 Enhanced Surface Water
Treatment Rule (LT2ESWTR). EPA
expects that the LT2ESWTR provisions
will prevent significant increases in
microbial risk resulting from the Stage
2 DBPR. EPA also expects the Ground
Water Rule, scheduled for promulgation
in 2003, to prevent any increases in
microbial risk in ground water systems
deemed vulnerable to source water
contamination.
/. Effects on General Population and
Subpopulation Groups
Section III of today's proposed rule
discusses the health effects associated
with DBFs on the general population as
well as the effects on pregnant women
and fetuses. In addition, health effects
associated with children and pregnant
women are discussed in greater detail in
subsection VIII.G of this preamble.
K. Uncertainties in Baseline, Risk,
Benefit, and Cost Estimates
Today's proposal models the current
baseline risk from DBF exposure as well
as the reduction in risk and the cost for
various rule options. There is
uncertainty regarding many aspects of
this analysis including the risk
calculation, the benefit estimate, and the
cost estimates. EPA has tried to capture
much of the uncertainty and also the
variability associated with many of the
inputs used in the economic analysis by
using distributions or ranges as model
inputs instead of point estimates
whenever possible. The Stage 2 DBPR
EA contains a more extensive
discussion of the modeling techniques
used to address uncertainty and
variability (USEPA 2003i).
In addition, the Agency conducted
sensitivity analyses to address
uncertainty. The sensitivity analyses
focus on various benefit and cost factors
that may have a significant influence on
the outcome of the rule. All of these
sensitivity analyses are explained in
more detail in the EA for the Stage 2
DBPR (USEPA 2003i).
The major source of benefit
uncertainty is the scientific uncertainty
regarding the impact of DBP exposure
on reproductive and developmental
outcomes. However, the Agency
believes that the monetized value of
these outcomes could be significant. As
discussed in subsection VII.C.l, EPA
performed an illustrative calculation
that explored the potential implications
for the proposed rule using some of the
published results on fetal loss, but did
not attempt to quantify benefits
associated with reducing other
reproductive and developmental
endpoints potentially associated with
DBP exposure.
Another possible underestimation of
today's monetized benefits results from
the inability of the Agency to quantify
or monetize the potential benefit from
avoiding other cancers associated with
DBP exposure such as colon and rectal
cancers. Furthermore, while the Agency
estimated the range of bladder cancer
risks avoided to be 0 to 182 cases per
year, the true risk of bladder cancer
avoided from decreased DBP exposure
may be higher than this range.
While EPA believes it has accounted
for the significant costs of today's
proposed rule, there are uncertainties
about some of the cost inputs. As
discussed in subsection VII.D.4, cost
estimates do not include some
alternatives to installing treatment (e.g.,
improving management of distribution
system residence time) that may be a
less costly means of complying with the
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
Stage 2 DBPR. The Agency also
explored two additional uncertainties
which might have the greatest impact on
our current estimates by conducting
sensitivity analyses. These include the
impact of IDSE monitoring and the
possibility that the primary analysis
overestimates the compliance forecast
for small surface water systems and all
ground water systems. A detailed
discussion of these analyses can be
found in chapter 7 of the Economic
Analysis (USEPA 2003i).
Last, EPA has recently proposed or
finalized new regulations for arsenic,
radon, and microbials in ground water
systems (Ground Water Rule);
Cryptosporidium in small surface water
systems and filter backwash in all
system sizes (LTlESWTR and Filter
Backwash Rule); as well as concurrently
proposing additional microbial control
in surface water systems (Long Term 2
Enhanced Surface Water Treatment
Rule). These rules may have
overlapping impacts on some drinking
water systems but it is not possible to
estimate these because of lack of
information on co-occurrence. However,
it is possible for a system to choose
treatment technologies that would
address multiple contaminants.
Therefore, the total cost impact of these
drinking water rules is uncertain;
however, it may be less than the
estimated total cost of all individual
rules combined.
L. Benefit/Cost Determination for the
Proposed Stage 2 DBPR
The Agency has determined that the
quantified and unquantified benefits of
the proposed Stage 2 DBPR justify the
costs. As discussed previously, the main
concern for the Agency and the
Advisory Committee involved in the
Stage 2 rulemaking process was to
address potential reproductive and
developmental impacts associated with
exposure to high DBF levels. The
proposed rule achieves this objective
using the least cost alternative by
modifying how the annual average DBF
level is calculated. This will reduce
both average DBF levels associated with
bladder cancer (and possibly other
cancers) and peak DBF levels which are
potentially associated with reproductive
and developmental effects. In addition,
this rule may reduce uncertainty about
drinking water quality and may allow
some systems to avoid installing
additional technology to meet future
drinking water regulations.
Compared to other rule options
consider by the Agency, the proposed
rule option is also the most cost-
effective. The cost-effectiveness analysis
compares the annual dollar cost of the
rule to the annual number of bladder
cancer cases potentially avoided. For
bladder cancer reduction, the cost per
case avoided for the proposed rule
would be $0.3 million if the PAR is
17%, and $3.1 million if the PAR is 2%,
and also varies depending on the
discount rate used.
M. Request for Comment
The Agency requests comment on all
aspects of the rule's economic impact
analysis. Specifically, EPA seeks input
into the following issues: (1) To what
extent can systems install treatment to
address multiple contaminants?; (2) Are
there methods for monetizing potential
reproductive and developmental
endpoints associated with DBF
exposure?; (3) To what extent will use
of chloramination increase levels of
NDMA and potentially associated health
risks, and how should this be
considered in this rule making; and (4)
How should the Agency value nonfatal
cancers? Specifically, EPA uses a range
of severities to calculate the WTP
estimate to avoid a case of chronic
bronchitis. Should the Agency only
consider the most severe case of chronic
bronchitis as a better proxy for a non-
fatal cancer? Also, should the Agency
use the risk-risk trade-off estimate of
WTP to avoid a case of chronic
bronchitis instead of the risk-dollar
trade-off estimate (see the EA (USEPA
2003i) for a complete discussion of
these issues)?
VIII. Statutory and Executive Order
Reviews
A. Executive Order 12866: Regulatory
Planning and Review
Under Executive Order 12866, (58 FR
51735, October 4,1993) the Agency
must determine whether the regulatory
action is "significant" and therefore
subject to OMB review and the
requirements of the Executive Order.
The Order defines "significant
regulatory action" as one that is likely
to result in a rule that may:
(1) Have an annual effect on the
economy of $100 million or more or
adversely affect in a material way the
economy, a sector of the economy,
productivity, competition, jobs, the
environment, public health or safety, or
State, local, or Tribal governments or
communities;
(2) Create a serious inconsistency or
otherwise interfere with an action taken
or planned by another agency;
(3) Materially alter the budgetary
impact of entitlements, grants, user fees,
or loan programs or the rights and
obligations of recipients thereof; or
(4) Raise novel legal or policy issues
arising out of legal mandates, the
President's priorities, or the principles
set forth in the Executive Order.
Pursuant to the terms of Executive
Order 12866, it has been determined
that this rule is a "significant regulatory
action." As such, this action was
submitted to OMB for review. Changes
made in response to OMB suggestions or
recommendations will be documented
in the public record.
B. Paperwork Reduction Act
The information collection
requirements in this proposed rule have
been submitted for approval to the
Office of Management and Budget
(OMB) under the Paperwork Reduction
Act, 44 U.S.C. 3501 et seq. The
Information Collection Request (ICR)
document prepared by EPA has been
assigned ICR No. 2068.01 (USEPA
2003m).
The information collected as a result
of this rule will allow the States and
EPA to determine appropriate
requirements for specific systems, and
to evaluate compliance with the rule.
For the first 3 years after Stage 2 DBPR
promulgation, the major information
requirements involve monitoring
activities, which include conducting the
IDSE and submission of the IDSE report,
and tracking compliance. The
information collection requirements are
mandatory (Part 141), and the
information collected is not
confidential.
The estimate of annual average
burden hours for the Stage 2 DBPR for
systems and States is 248,568 hours.
This estimate covers the first three years
of the Stage 2 DBPR and includes
implementation of Stage 2A and most of
the IDSE (small system reports are not
due until the fourth year). The annual
average aggregate cost estimate is $18.0
million for operation and maintenance
as a purchase of service for lab work,
and $6.8 million is associated with
labor. The annual burden hour per
response is 2.59 hours. The frequency of
response (average responses per
respondent) is 11.8 annually. The
estimated number of likely respondents
is 8,131 per year (the product of burden
hours per response, frequency, and
respondents does not total the annual
average burden hours due to rounding).
Because disinfecting systems have
already purchased basic monitoring
equipment to comply with the Stage 1
DBPR, EPA assumes no capital start-up
costs are associated with the Stage 2
DBPR ICR.
Burden means the total time, effort, or
financial resources expended by persons
to generate, maintain, retain, or disclose
or provide information to or for a
Federal agency. This includes the time
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
49649
needed to review instructions; develop,
acquire, install, and utilize technology
and systems for the purposes of
collecting, validating, and verifying
information, processing and
maintaining information, and disclosing
and providing information; adjust the
existing ways to comply with any
previously applicable instructions and
requirements; train personnel to be able
to respond to a collection of
information; search data sources;
omplete and review the collection of
information; and transmit or otherwise
disclose the information.
An Agency may not conduct or
sponsor, and a person is not required to
respond to a collection of information
jnless it displays a currently valid OMB
control number. The OMB control
lumbers for EPA's regulations in 40
:FR are listed in 40 CFR part 9.
To comment on the Agency's need for
:his information, the accuracy of the
provided burden estimates, and any
mggested methods for minimizing
•espondent burden, including the use of
lutomated collection techniques, EPA
las established a public docket for this
•ule, which includes this ICR, under
Docket ID No. OW-2002-0043,Submit
my comments related to the ICR for this
proposed rule to EPA and OMB. See
ADDRESSES section at the beginning of
his notice for where to submit
;omments to EPA. Send comments to
3MB at the Office of Information and
Regulatory Affairs, Office of
Management and Budget, 725 17th
Street, NW., Washington, DC 20503,
\ttention: Desk Office for EPA. Since
DMB is required to make a decision
:oncerning the ICR between 30 and 60
lays after August 18, 2003, a comment
to OMB is best assured of having its full
effect if OMB receives it by September
17, 2003. The final rule will respond to
any OMB or public comments on the
information collection requirements
contained in this proposal.
C. Regulatory Flexibility Act
The Regulatory Flexibility Analysis
(RFA), as amended by the Small
Business Regulatory Enforcement
Fairness Act (SBREFA) of 1996, 5 U.S.C.
601 et seq., generally requires an agency
to prepare a regulatory flexibility
analysis of any rule subject to notice
and comment rulemaking requirements
under the Administrative Procedure Act
or any other statute, unless the Agency
certifies that the rule will not have a
significant economic impact on a
substantial number of small entities.
Small entities include small businesses,
small organizations, and small
governmental jurisdictions.
The RFA provides default definitions
for each type of small entity. It also
authorizes an agency to use alternative
definitions for each category of small
entity, "which are appropriate to the
activities of the agency" after proposing
the alternative definition(s) in the
Federal Register and taking comment. 5
U.S.C. 601(3) through (5). In addition to
the above, to establish an alternative
small business definition, agencies must
consult with SBA's Chief Counsel for
Advocacy.
For purposes of assessing the impacts
of today's proposed rule on small
entities, EPA considered small entities
to be public water systems serving
10,000 or fewer persons. This is the cut-
off level specified by Congress in the
1996 Amendments to the Safe Drinking
Water Act for small system flexibility
provisions. In accordance with the RFA
requirements, EPA proposed using this
alternative definition in the Federal
Register (63 FR 7620 (February 13,
1998}), requested public comment,
consulted with the Small Business
Administration (SBA), and expressed its
intention to use the alternative
definition for all future drinking water
regulations in the Consumer Confidence
Reports regulation (63 FR 44511 (August
19,1998)}. As stated in that final rule,
the alternative definition is applied to
this regulation.
After considering the economic
impacts of today's proposed rule on
small entities, I certify that this action
will not have a significant economic
impact on a substantial number of small
entities. We have determined that 75
small systems using surface water or
ground water under the direct influence
of surface water (GWUDI), which are
1.67% of all such systems affected by
the Stage 2 DBPR, will experience an
impact of greater than or equal to 1% of
their revenues, and 49 small systems
using surface water or GWUDI, which
are 1.09% of all such systems affected
by the Stage 2 DBPR, will experience an
impact of greater than or equal to 3% of
their revenues; further, 109 small
ground water systems, which are 0.28%
of all such systems affected by the Stage
2 DBPR, will experience an impact of
greater than or equal to 1% of their
revenues, and 38 small ground water
systems, which are 0.10% of all such
systems affected by the Stage 2 DBPR,
will experience an impact of greater
than or equal to 3% of their revenues
(see Tables VIII-1 and VIII-2}.
BILLING CODE 6560-50-P
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49650
Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
Table VII1-1. Annualized Compliance Cost as a Percentage of Revenues or Expenditures for
All Small Entities Using Surface Water and GWUDI.
Entity by
System Size
Small Governments
<100
101-500
501-1,000
1,001-3,300
3,301-10,000
Small Businesses
<100
101-500
501-1,000
1,001-3,300
3,301-10,000
Small Organizations
<100
101-500
501-1,000
1,001-3,300
3,301-10,000
All Small Entities
<100
101-500
501-1,000
1,001-3,300
3,301-10,000
Number of
Small Systems
(Percent)
A
2,238 50%
384.
513;
283 i
538 1
519[
1.B35J 41%
315!
421 i
232!
441 i
426 1
403! 9%
69;
92'
51 !
97;
94i
4,476 100%
768i
1,027!
567!
1,0751
1,039;
Average
Annual
Estimated
Revenues1
per System ($)
B
$2,396,249
$2,396,249
$2,396,249
$2,396,249
$2,396,249
$2,396,249
$2,391,978
$2,391,978
$2,391,978
$2,391,978
$2,391,978
$2,391,978
$4,446,165
$4,446,165
$4,446,165
$4,446,165
$4,446,165
$4,446,165
$2,578,991
$2,578,991
$2,578,991
$2,578,991
$2,578,991
$2.578,991
Experiencing Costs
of >1% of their
Revenues
Percent of
Systems
E
1.67%
1.27%
1.53%
1.58%
1.79%
5.61%
1.67%
1.27%
1.57%
1.58%
1.79%
5.61%
1.27%
0.00%
1.44%
1.46%
1.32%
5.02%
1.67%
1.27%
1.44%
1.58%
1.55%
5.61%
Number
of
Systems
F=A*E
37
5
8
4
10
29
31
4
7
4
8
24
5
-
1
1
1
5
75
10
15
9
17
58
Experiencing Costs
of >3% of their
Revenues
Percent
of
Systems
G
1.09%
0.00%
1.17%
1.46%
1.32%
3.71%
1.09%
0.00%
1.17%
1.46%
1.32%
3.71%
0.76%
0.00%
0.61%
0.75%
0.93%
. 3.71%
1.09%
0.00%
1.17%
1.46%
1.32%
3.71%
Number
of
Systems
H*A*G
24
-
6
4
7
19
20
-
5
3
6
16
3
-
1
0
1
3
49
, -
12
8
14
39
1 Revenue information was used whenever available. When it was not available, different measures, such as sales or
annual operating expenditures, were used. Data were not available to differentiate revenue by system size.
Note: Detail may not add due to independent rounding.
Source: Economic Analysis (USEPA 2003i)
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
49651
Table VJII-2. Annualized Compliance Cost as a Percentage of Revenues or Expenditures for
AH Small Entities Using Ground Water Only.
Entity by
System Size
Small Governments
<100
101-500
501-1,000
1,001-3,300
3,301-10,000
Small Businesses
<100
101-500
501-1,000
1,001-3,300
3,301-10,000
Small Organizations
<100
101-500
501-1,000
1,001-3,300
3,301-10,000
AH Small Entities
<100
101-500
501-1,000
1,001-3,300
3,301-10,000
Number of
Small Systems
(Percent)
A
19,133! 50%
5.641J
7,269;
2,403!
2,599|
1.221!
15,689 41%
4,625!
5,960;
1,970;
2,131 i
1,00V
3,444; 9%
1,015
1,308!
433i
468!
220i
38,265! 100%
11,282;
14,537;
4,806;
5,198!
2.443J
Average
Annual
Estimated
Revenues1
per System ($)
B
$2,396,249
$2,396,249
$2,396,249
$2,396,249
$2,396,249
$2,396,249
$2,391,978
$2,391,978
$2,391,978
$2,391,978
$2,391,978
$2,391,978
$4,446,165
$4,446,165
$4,446,165
$4,446,165
$4,446,165
$4,446,165
$2,578,991
$2,578,991
$2,578,991
$2,578,991
$2,578,991
$2,578,991
Experiencing Costs
of >1% of their
Revenues
Percent of
Systems
E
0.28%
0.00%
0.13%
0.75%
1.26%
1.32%
0.28%
0.00%
0.13%
0.75%
1.26%
1.32%
0.10%
0.00%
0.00%
0.14%
0.04%
1.32%
0.28%
0.00%
0.13%
0.14%
1.26%
.1.32%
Number
of
Systems
FsA*E
54
-
9
18
33
16
44
-
8
15
27
13
4
-
-
1
0
3
109
-
19
7
66
32
Experiencing Costs
of >3% of their
Revenues
Percent
of
Systems
G
0.10%
0.00%
0.00%
0.07%
0.04%
1.32%
0.10%
0.00%
0.00%
0.07%
0.04%
1.32%
0.01%
0.00%
0.00%
0.00%
0.02%
0.04%
0.10%
0.00%
0.00%
0.07%
0.04%
1.32%
Number
of
Systems
H*A*G
19
-
- .
2
1
16
16
-
-
1
1
13
0
-
-
-
0
0
38
.-
-
3
2
32
1 Revenue information was used whenever available. When it was not available, different measures, such as sales or
annual operating expenditures, were used. Data were not available to differentiate revenue by system size.
Note: Detail may not add due to independent rounding.
Source: Economic Analysis (USEPA 2003i)
JLUNG CODE 6560-50-C
As a result of the input received from
takeholders, the EPA workgroup, the
Advisory Committee, and other
nterested parties, EPA has developed
4CLs using locational running annual
verages (LRAA) of 0.080 and 0.060 mg/
, for TTHM and HAAS respectively, in
ombination with Initial Distribution
iystems Evaluations (IDSE), as the
'referred Stage 2 DBPR option. LRAAs
re running annual averages calculated
ar each sample location in the
istribution system. Since many small
ystems only monitor at one location,
they will effectively base their
compliance with the Stage 1 DBPR on
an LRAA and therefore will not be
significantly affected by the Stage 2
DBPR. In addition to meeting the MCLs
for TTHM and HAAS, systems will be
required to conduct IDSEs. The purpose
of the IDSE is to identify compliance
monitoring sites representing high
TTHM and HAAS levels in the
distribution system. According to the
Stage 2 DBPR Economic Analysis
(USEPA 2003i), only 17% of all small
water systems will conduct IDSE
monitoring because small NTNCWSs are
exempt from IDSE monitoring, systems
serving fewer than 500 people may
receive a waiver from their States, and
other systems are eligible for a 40/30
certification if all compliance
monitoring samples have been < 0.040
and < 0.030 mg/L for TTHM and HAAS
respectively during the previous two
years. A large number of small ground
water systems will qualify for this
certification. This provision is described
in more detail in section V.H. of this
preamble.
Although not required by the RFA to
convene a Small Business Advocacy
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49652
Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
Review (SBAR) Panel because EPA
determined that this proposal would not
have a significant economic impact on
a substantial number of small entities,
EPA did convene a panel to obtain
advice and recommendations from
representatives of the small entities
potentially subject to this rule's
requirements.
Before convening the SBAR Panel,
EPA consulted with a group of 24 SERs
likely to be impacted by the Stage 2 M-
DBP Rules. The SERs included small
system operators, local government
officials, and small nonprofit
organizations. The SERs were provided
with background information on the
Safe Drinking Water Act, Stage 1 DBPR,
IESWTR, and Stage 2 DBPR alternatives
and unit cost analyses resulting from
using different technologies to meet the
required MCLs in preparation for the
teleconferences on January 28, 2000,
February 25, 2000, and April 7, 2000.
This information package included data
on options and preliminary unit costs
for treatment enhancements under
consideration. It is important to note
that, since EPA did not consider the
IDSE requirements until after these
consultations with SERs and the SBAR
panel, no comments were received on
the IDSE requirements from the SERs or
the SBAR panel. However, small system
representatives were included in the
Advisory Committee that recommended
the IDSE.
During these conference calls, the
information was discussed and EPA
provided feedback and noted these
initial SER comments. Following the
calls, the SERs were asked to provide
input on the potential impacts of the
rule. Seven SERs provided written
comments on these materials. These
comments were provided to the SBAR
Panel when the Panel convened in April
25, 2000. After a teleconference between
the SERs and the Panel on May 25,
2000, the SERs were invited to provide
additional comments on the information
provided. Seven SERs provided
additional comments on the rule
components.
In general, the SERs consulted on the
Stage 2 M-DBP rules were concerned
about the impact of these proposed rules
on small water systems. They were
particularly concerned with acquiring
the technical and financial capability to
implement requirements, maintaining
flexibility to tailor requirements to their
needs, and the limitations of small
systems.
The Small Business Advocacy Review
(SBAR) Panel members for the Stage 2
DBPR were: the Small Business
Advocacy Chair of the Environmental
Protection Agency, the Chief of the
Standards and Risk Reduction Branch of
the Office of Ground Water and
Drinking Water within EPA's Office of
Water, the Administrator of the Office of
Information and Regulatory Affairs
within the Office of Management and
Budget, and the Chief Counsel for
Advocacy of the Small Business
Administration. The Panel convened on
April 25, 2000, and met five times
before the end of the 60-day Panel
period on June 23, 2000. The SBAR
Panel's report, "Final Report of the
Small Business Advocacy Review Panel
on Stage 2 Disinfectants and
Disinfection Byproducts Rule (Stage 2
DBPR) and Long-Term 2 Enhanced
Surface Water Treatment Rule
(LT2ESWTR)", the Small Entity
Representatives (SERs) comments on
components of the Stage 2 MDBP Rules,
and the background information
provided to the SBAR Panel and the
SERs are available for review in the
Office of Water Docket.
Today's proposal takes into
consideration the recordkeeping and
reporting concerns identified by the
Panel and the SERs. The Panel
recommended that EPA evaluate ways
to minimize the rule recordkeeping and
reporting burdens by ensuring that
States have appropriate capacity for rule
implementation and that EPA provide
as much monitoring flexibility as
possible to small systems. Continuity
with the Stage 1 DBPR was maintained
to the extent possible to ease the
transition to the Stage 2 DBPR,
especially for small systems. EPA's
decision to maintain the same MCLs for
TTHM and HAAS will also help to
minimize the additional
implementation burden. Generally,
routine monitoring will be similar in
frequency to monitoring for the Stage 1
DBPR, and systems with low DBF levels
will still be eligible for reduced
monitoring. Many small systems will
conduct the same amount of monitoring
for the Stage 2 DBPR as for the Stage 1
DBPR. Surface and ground water
community water systems (CWSs)
serving 500 to 9,999 people and ground
water systems serving at least 10,000
people may be required to add one
sampling site and take an additional
quarterly TTHM/HAA5 sample at that
site. Also, EPA has specified
consecutive system requirements; these
will be new requirements in States
where consecutive systems are not
required to comply with some or all
Stage 1 DBPR requirements. As noted
before, since some small systems will be
effectively complying with such
requirements under the Stage 1 DBPR,
the Stage 2 DBPR will not impose any
additional burden on them.
The Panel also noted the concern of
several SERs that flexibility should be
provided in the compliance schedule of
the rule. SERs noted the technical and
financial limitations that some small
systems will have to address, the
significant learning curve for operators
with limited experience, and the need to
continue providing uninterrupted
service as reasons why additional
compliance time may be needed for
small systems. The panel encouraged
EPA to keep these limitations in mind
in developing the proposed rule and
provide as much compliance flexibility
to small systems as is allowable under
the SDWA. EPA believes that the
proposed compliance schedules
provides sufficient time for small
systems to achieve compliance.
Under the proposed LT2ESWTR,
certain subpart H systems with low
levels of indicators such as E. coli will
not have to monitor for
Cryptosporidium. The efficacy of E. coli
as an indicator will be evaluated using
the large system data. Thus, small
systems E. coli monitoring cannot be
initiated until large and medium system
monitoring has been completed. The
LT2ESWTR compliance time line for
small systems thus lags 1.5 to 2.5 years
behind the large and medium systems;
timeline. Because the Stage 2 DBPR
must be implemented on a simultaneous
schedule, the compliance timeline is
similarly delayed 1.5 to 2.5 years behind
large and medium systems. In addition,
if capital improvements are necessary
for a particular PWS to comply, a State
may allow the system up to an
additional two years to comply with the
MCL. The Agency is developing
guidance manuals to assist small
entities with their compliance efforts.
The Panel considered a wide range of
options and regulatory alternatives for
providing small businesses with
flexibility in complying with the Stage
2 DBPR. The Panel recognized the
concern shared by most stakeholders
regarding the need to reduce DBP
variability in the distribution system.
This concern comes from recent studies
that, while not conclusive, suggest that
there may be adverse reproductive
effects associated with relatively short-
term exposure to high levels of DBFs.
Many small systems will be monitoring
at only a single point in the distribution
system (designed to represent the point
of maximum TTHM and HAAS
exposure), and many small systems will
be monitoring only once during the
year, at a time which corresponds to the
season with the highest potential
occurrence.
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
49653
Since there is a chance for this single
sample to exceed an MCL, today's
proposal requires systems that exceed
an MCL on an annual or less frequent
sample to begin increased (quarterly)
monitoring rather than immediately
being in violation of the MCL. The
system must comply with the MCL as an
LRAA once it has collected four
quarterly samples. This allows small
systems to generally monitor less
frequently (to reduce their monitoring
burden) during the period when the
highest DBF levels are expected (to
protect public health) without
penalizing them (by requiring them to
meet an MCL that would effectively be
based on a single highest value if the
systems were immediately in violation
after a single sample exceeds an MCL).
This compliance determination is
consistent with requirements for
systems that monitor quarterly for
whom compliance is based on the
compliance monitoring results of the
previous four quarters.
It is important to note that based on
the IDSE results, some small systems
will have a high TTHM site that is
different from the high HAAS site.
These systems will need to monitor at
two sites under the Stage 2 DBPR. EPA
relieves that an approach based on
compliance with 0.080 mg/L TTHM and
0.060 mg/L HAA5 LRAAs is an effective
way of addressing concerns regarding
ocational variability.
In addressing seasonal variability, the
3anel was concerned about a regulatory
alternative requiring compliance with
0.080 mg/L TTHM and 0.060 mg/L
3AA5 single highest value MCL
Alternative 2), because it would impose
significant additional cost on some
small systems. The Panel recommended
hat EPA instead explore an approach
under which individual high values
might trigger additional assessment and/
or notification requirements, rather than
an MCL violation.
EPA agrees with the panel
ecommendations on a single highest
falue MCL. Under today's proposal,
lublic water systems are required to
maintain a record of TTHM and HAAS
oncentrations detected at each sample
ocation. As part of the sanitary survey
irocess, systems are required to conduct
n evaluation and consult with their
State regarding significant excursions in
TTHM and HAAS occurrence that have
)ccurred. EPA is developing guidance
or public water systems and States on
low to identify significant excursions
nd conduct significant excursion
valuations, and how to reduce DBP
3vels through actions such as
istribution system operational changes
USEPA 2003n) (Section V.E.).
The Panel noted the strong concerns
expressed by some SERs about the
uncertainty in the current scientific
evidence regarding health effects from
exposure to DBFs, particularly regarding
short term exposure. A Panel member
recommended that EPA give further
serious consideration to making a
determination that the currently
available scientific evidence does not
warrant imposing additional regulatory
requirements beyond those in the Stage
1 DBPR at this time. This Panel member
recommended that EPA instead
continue to vigorously fund ongoing
research in health effects, occurrence,
and appropriate treatment techniques
for DBFs, and reconsider whether
additional requirements are appropriate
during its next SDWA required six-year
review of the standard. This panel
member also recommended that EPA
separately explore whether adequate
data exist to warrant regulation of
NTNCWSs at a national level at this
time.
EPA has considered these
recommendations and believes the Stage
2 DBPR is needed at this time to protect
public health. EPA's main mission is the
protection of human health and the
environment. When carrying out this
mission, EPA must often make
regulatory decisions with less than
complete information and with
uncertainties in the available
information. EPA believes it is
appropriate and prudent to err on the
side of public health protection when
there are indications that exposure to a
contaminant may present risks to public
health, rather than take no action until
risks are unequivocally proven.
Therefore, while recognizing the
uncertainties in the available
information, EPA believes that the
weight of evidence represented by the
available epidemiology and toxicology
studies on chlorinated water and DBFs
supports a hazard concern and a
protective public health approach to
regulation. In addition, EPA has an
ongoing research program to study DBP
health effects, occurrence, and
treatment.
EPA continues to be interested in the
potential impacts of the proposed rule
on small entities and welcome
comments on issues related to such
impacts.
D. Unfunded Mandates Reform Act
Title II of the Unfunded Mandates
Reform Act of 1995 (UMRA), Public
Law 104-4, establishes requirements for
Federal agencies to assess the effects of
their regulatory actions on State, local,
and Tribal governments and the private
sector. Under UMRA section 202, EPA
generally must prepare a written
statement, including a cost-benefit
analysis, for proposed and final rules
with "Federal mandates" that may
result in expenditures by State, local,
and Tribal governments, in the
aggregate, or by the private sector, of
$100 million or more in any one year.
Before promulgating an EPA rule for
which a written statement is needed,
section 205 of the UMRA generally
requires EPA to identify and consider a
reasonable number of regulatory
alternatives and adopt the least costly,
most cost-effective or least burdensome
alternative that achieves the objectives
of the rule. The provisions of section
205 do not apply when they are
inconsistent with applicable law.
Moreover, section 205 allows EPA to
adopt an alternative othor than the least
costly, most cost-effective or least
burdensome alternative if the
Administrator publishes with the final
rule an explanation why that alternative
was not adopted.
Before EPA establishes any regulatory
requirements that may significantly or
uniquely affect small governments,
including Tribal governments, it must
have developed, under section 203 of
the UMRA, a small government agency
plan. The plan must provide for
notifying potentially affected small
governments, enabling officials of
affected small governments to have
meaningful and timely input in the
development of EPA regulatory
proposals with significant Federal
intergovernmental mandates and
informing, educating, and advising
small governments on compliance with
the regulatory requirements.
EPA has determined that this rule
does not contain a Federal mandate that
may result in expenditures of $100
million or more for State, local and
Tribal governments, in the aggregate, or
the private sector in any one year. Based
on total estimated nominal costs
incurred by year, costs for public or
private systems are not expected to
exceed $100 million in any one year. In
addition, total estimated annualized
costs of this rule are $59 to $65 million
for all systems, including labor burdens
that States would face, such as training
employees on the requirements of the
Stage 2 DBPR, responding to PWS
reports, and record keeping. Thus,
today's proposed rule is not subject to
the requirements of sections 202 and
205 of the UMRA.
EPA has determined that the Stage 2
DBPR contains no regulatory
requirements that might significantly or
uniquely affect small governments (see
Tables VIII-1 and VIII-2). Since the
Stage 2 DBPR affects all size systems
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and the impact on small entities will be
0.00 to 0.11 percent of revenues, the
Stage 2 DBPR is not subject to the
requirements of section 203 of UMRA.
Nevertheless, in developing this rule,
EPA consulted with small governments
(see sections VIII.B., VIII.C. and VIII.F.).
In preparation for the proposed Stage 2
DBPR, EPA conducted an analysis of
small government impacts and included
small government officials or their
designated representatives in the
rulemaking process. As noted
previously, a variety of stakeholders,
including small governments, had the
opportunity for timely and meaningful
participation in the regulatory
development process through the
SBREFA process, public stakeholder
meetings, and Tribal meetings.
Representatives of small governments
took part in the SBREFA process for this
rulemaking and they attended public
stakeholder meetings. Through such
participation and exchange, EPA
notified several potentially affected
small governments of requirements
under consideration and provided
officials of affected small governments
with an opportunity to have meaningful
and timely input into the development
of this regulatory proposal.
The Agency has developed fact sheets
that describe requirements of the
proposed Stage 2 DBPR. These fact
sheets are available by calling the Safe
Drinking Water Hotline at 800-426-
4791.
E. Executive Order 13132: Federalism
Executive Order 13132, entitled
"Federalism" (64 FR 43255, August 10,
1999), requires EPA to develop an
accountable process to ensure
"meaningful and timely input by State
and local officials in the development of
regulatory policies that have federalism
implications." "Policies that have
federalism implications" is defined in
the Executive Order to include
regulations that have "substantial direct
effects on the States, on the relationship
between the national government and
the States, or on the distribution of
power and responsibilities among the
various levels of government."
This proposed rule will not have
federalism implications. It will not
impose substantial direct effects on the
States, on the.relationship between the
national government and the States, or
on the distribution of power and
responsibilities among the various
levels of government, as specified in
Executive Order 13132. The proposed
rule has one-time costs for
implementation of approximately $68.5
million. Thus, Executive Order 13132
does not apply to this rule.
Although Executive Order 13132 does
not apply to this rule, EPA did consult
with State and local officials in
doveloping this proposed regulation. On
February 20, 2001, EPA held a dialogue
on both the Stage 2 DBPR and
LT2ESWTR with representatives of
State and local governmental
organizations including those that
represent elected officials.
Representatives from the following
organizations attended the consultation
meeting: Association of State Drinking
Water Administrators (ASDWA), the
National Governors' Association (NGA),
the National Conference of State
Legislatures (NCSL), the International
City/County Management Association
(ICMA), the National League of Cities
(NLC), the County Executives of
America, and health departments. At
the consultation meeting, questions
ranged from a basic inquiry into how
Cryptosporidium gets into water to more
detailed queries about anticipated
implementation guidance, procedures,
and schedules. No concerns were
expressed. Some of the State and local
organizations who attended the
governmental dialogue on upcoming
microbial and disinfection byproduct
rulemakings were also participants in
the Advisory Committee meetings and
signed the Agreement in Principle. In
addition, EPA consulted with a mayor
in the SBREFA consultation described
in section VIII B.
In the spirit of Executive Order 13132,
and consistent with EPA policy to
promote communications between EPA
and State and local governments, EPA
specifically solicits comment on this
proposed rule from State and local
officials.
F. Executive Order 13175: Consultation
and Coordination With Indian Tribal
Governments
Executive Order 13175, entitled
"Consultation and Coordination with
Indian Tribal Governments" (65 FR
67249, November 9, 2000), requires EPA
to develop "an accountable process to
ensure meaningful and timely input by
tribal officials in the development of
regulatory policies that have tribal
implications." "Policies that have tribal
implications" is defined in the
Executive Order to include regulations
that have "substantial direct effects on
one or more Indian tribes, on the
relationship between the Federal
government and the Indian tribes, or on
the distribution of power and
responsibilities between the Federal
government and Indian tribes."
Under Executive Order 13175, EPA
may not issue a regulation that has
Tribal implications, that imposes
substantial direct compliance costs, and
that is not required by statute, unless
the Federal government provides the
funds necessary to pay the direct
compliance costs incurred by Tribal
governments, or EPA consults with
Tribal officials early in the process of
developing the proposed regulation and
develops a Tribal summary impact
statement.
EPA has concluded that this proposed
rule may have Tribal implications
because it may impose substantial direct
compliance costs on Tribal
governments, and the Federal
government will not provide the funds
necessary to pay those costs.
Total Tribal costs are estimated to be
approximately $199,372 per year (at a 3
percent discount rate) and this cost is
distributed across 559 Tribal systems.
The cost for individual systems depend
on system size and source water type.
Of the 559 Tribes that may be affected
in some form by the Stage 2 DBPR, 502
use ground water as a source and 57
systems use surface water or GWUDI.
Since the majority of Tribal systems are
ground water systems serving fewer
than 500 people, less than 10 percent of
all Tribal systems will likely have to
conduct an IDSE. As a result, the Stage
2 DBPR is most likely to have an impact
on Tribes using surface water or GWUDI
serving more than 500 people.
Accordingly, EPA provides the
following Tribal summary impact
statement as required by section 5(b) of
Executive Order 13175. EPA provides
further detail on Tribal impact in the
Economic Analysis for the Stage 2
Disinfectants and Disinfection
Byproduct Rule (USEPA 2003i).
EPA consulted with Tribal officials
early in the process of developing this
regulation to permit them to have
meaningful and timely input into its
development. Consistent with Executive
Order 13175, EPA engaged in outreach
and consultation efforts with Tribal
officials in the development of this
proposed regulation. The most long-
term participation of Tribes was on the
Advisory Committee through a
representative of the All Indian Pueblo
Council (AIPC), which is associated
with approximately 20 Tribes.
In addition to obtaining Tribal input
during the Advisory Committee
negotiations, EPA presented the Stage 2
DBPR at the 16th Annual Consumer
Conference of the National Indian
Health Board, the Environmental
Council's Annual Conference, and the
EPA/Inter-Tribal Council of Arizona,
Inc. Over 900 attendees representing
Tribes from across the country attended
the National Indian Health Board's
Consumer Conference and over 100
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49655
Tribes were represented at the annual
conference of the National Tribal
Environmental Council. Representatives
from 15 Tribes participated at the EPA/
Inter-Tribal Council of Arizona meeting.
At the first two conferences, an EPA
representative conducted workshops on
EPA's drinking water program and
upcoming regulations, including the
Stage 2 DBPR. EPA sent the presentation
materials and a meeting summary to
over 500 Tribes and Tribal
organizations.
Fact sheets describing the
requirements of the proposed rule and
requesting Tribal input were distributed
at an annual EPA Tribal meeting in San
Francisco, and at a Native American
Water Works Association meeting in
Scottsdale, Arizona. EPA also worked
through its Regional Indian
Coordinators and the National Tribal
Operations Committee to raise
awareness of the development of the
proposed rule. EPA mailed fact sheets
on the Stage 2 DBPR to all of the
federally recognized Tribes in
November 2000, as well as the Tribal
Caucus of the National Tribal
Operations Committee.
A few Tribes responded by requesting
more information and expressing
concern about having to implement too
many regulations. Some members of the
Tribal Caucus noted that the rule would
lave a benefit. They also expressed a
concern about infrastructure costs and
:he lack of funding attached to the rule.
n response to one Tribal
representative's comments on the
skwember 2000 mailout, EPA explained
he health protection benefit expected to
ie gained by this proposed rule. EPA
also directed those who asked for more
nformation to the Agreement in
'rinciple on the EPA Web site.
EPA also held a teleconference for
'ribal representatives on January 24,
2002. Prior to the teleconference,
nvitations were sent to all of the
rederally-recognized Tribes, along with
act sheets explaining the rule. Twelve
rribal representatives and four regional
'ribal Program Coordinators attended.
'he Tribal representatives requested
urther explanation of the rule and
xpressed concerns about funding
ources. EPA also received calls from
'ribes after the teleconference which
>rovided EPA with further feedback. In
spirit of Executive Order 13175, and
onsistent with EPA policy to promote
onsultation between EPA and Tribal
overnments, EPA specifically solicits
dditional comment on this proposed
•ule from Tribal officials.
G. Executive Order 13045: Protection of
Children From Environmental Health
and Safety Risks
Executive Order 13045: "Protection of
Children From Environmental Health
Risks and Safety Risks" (62 FR 19885,
April 23, 1997) applies to any rule that:
(1) Is determined to be "economically
significant" as defined under Executive
Order 12866, and; (2) concerns an
environmental health or safety risk that
EPA has reason to believe may have a
disproportionate effect on children. If
the regulatory action meets both criteria,
the Agency must evaluate the
environmental health or safety effects of
the planned rule on children, and
explain why the planned regulation is
preferable to other potentially effective
and reasonably feasible alternatives
considered by the Agency.
While this proposed rule is not
subject to the Executive Order because
it is not economically significant as
defined in Executive Order 12866, EPA
nonetheless has reason to believe that
the environmental health or safety risk
(i.e., the risk associated with DBPs)
addressed by this action may have a
disproportionate effect on children. As
a matter of EPA policy, we have
therefore assessed the environmental
health or safety effect of DBPs on
children. EPA has consistently and
explicitly considered risks to infants
and children in all assessments
developed for this rulemaking. The
results of the assessments are contained
in section III of this preamble, Health
Risks to Fetuses, Infants, and Children:
A Review (USEPA 2003a), and in the
Economic Analysis (USEPA 2003i). A
copy of all documents has been placed
in the public docket for this action.
EPA's Office of Water has historically
considered risks to sensitive
subpopulations (including fetuses,
infants, and children) in establishing
drinking water assessments, health
advisories or other guidance, and
standards (USEPA 1989c and USEPA
1991a). Waterborne disease from
pathogens in drinking water is a major
concern for children and other
subgroups (elderly, immune
compromised, pregnant women)
because of their increased
vulnerabilities (Gerba et al 1996). There
is a concern for potential reproductive
and developmental risks posed by DBPs
to children and pregnant women
(USEPA 1994b; USEPA 1998c, Reif et al.
2000; Tyl, 2000). Specific to this action,
human epidemiology and animal
toxicology studies on DBPs have shown
potential increased risks for
spontaneous abortion, still birth, neural
tube defects, cardiovascular effects and
low birth weight. This rule is designed
to lower those risks. EPA has provided
an illustrative calculation of potential
fetal losses avoided in section VII.C.l.
Section V.D of this preamble presents
the regulatory alternatives that EPA
evaluated for the proposed Stage 2
DBPR, and the Economic Analysis
(USEPA 2003i) provides a more detailed
discussion. The Agency considered four
alternatives involving different MCLs
and different compliance calculations.
The proposed alternative was
recommended by the Advisory
Committee and selected by EPA as the
Preferred Regulatory Alternative
because it provides significant public
health benefits for an acceptable cost.
EPA's analysis of benefits and costs
indicates that the proposed alternative
is superior among those evaluated with
respect to maximizing net benefits, as
shown in the Economic Analysis
(USEPA 2003i). The result of the Stage
2 DBPR may include a reduction in
reproductive and developmental risk to
children and pregnant women and a
reduction in cancer risk.
It should also be noted that the
LT2ESWTR, which will be implemented
at the same time as this proposed rule,
provides better controls of pathogens
and achieves the goal of increasing
microbial drinking water protection for
children. The public is invited to submit
or identify peer-reviewed studies and
data, of which EPA may not be aware
that assessed results of early life
exposure to DBPs.
H, Executive Order 13211: Actions That
Significantly Affect Energy Supply,
Distribution, or Use
The proposed Stage 2 DBPR is not a
"significant energy action" as defined in
Executive Order 13211, "Actions
Concerning Regulations That
Significantly Affect Energy Supply,
Distribution, or Use" (66 FR 28355 (May
22, 2001)) because it is not likely to
have a significant adverse effect on the
supply, distribution, or use of energy.
This determination is based on the
following analysis.
The first consideration is whether the
Stage 2 DBPR would adversely affect the
supply of energy. The Stage 2 DBPR
does not regulate power generation,
either directly or indirectly. The public
and private utilities that the Stage 2
DBPR regulates do not, as a rule,
generate power. Further, the cost
increases borne by customers of water
utilities as a result of the Stage 2 DBPR
are a low percentage of the total cost of
water, except for a very few small
systems that might install advanced
technologies that must spread that cost
over a narrow customer base. Therefore,
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the customers that are power generation
utilities are unlikely to face any
significant effects as a result of the Stage
2 DBPR. In sum, the Stage 2 DBPR does
not regulate the supply of energy, does
not generally regulate the utilities that
supply energy, and is unlikely
significantly to affect the customer base
of energy suppliers. Thus, the Stage 2
DBPR would not translate into adverse
effects on the supply of energy.
The second consideration is whether
the Stage 2 DBPR would adversely affect
the distribution of energy, The Stage 2
DBPR does not regulate any aspect bf
energy distribution. The utilities that are
regulated by the Stage 2 DBPR already
have electrical service. As derived later
in this section, the proposed rule is
projected to increase peak electricity
demand at water utilities by only 0.007
percent. Therefore, EPA estimates that
the existing connections are adequate
and that the Stage 2 DBPR has no
discernable adverse effect on energy
distribution.
The third consideration is whether
the Stage 2 DBPR would adversely affect
the use of energy. Because some
drinking water utilities are expected to
add treatment technologies that use
tiloctrical power, this potential impact is
evaluated in more detail. The analyses
that underlay the estimation of costs for
the Stage 2 DBPR are national in scope
and do not identify specific plants or
utilities that may install treatment in
response to the rule. As a result, no
analysis of the effect on specific energy
suppliers is possible with the available
data. The approach used to estimate the
impact of energy use, therefore, focuses
on national-level impacts. The analysis
estimates the additional energy use due
to the Stage 2 DBPR, and compares that
to the national levels of power
generation in terms of average and peak
loads.
The first step in the analysis is to
estimate the energy used by the
technologies expected to be installed as
a result of the Stage 2 DBPR. Energy use
is not directly stated in Technologies
and Costs for Control ofMicrobia]
Contaminants and Disinfection By-
Products (USEPA 2003k), but the annual
cost of energy for each technology
addition or upgrade necessitated by the
Stage 2 DBPR is provided. An estimate
of plant-level energy use is derived by
dividing the total energy cost per plant
for a range of flows by an average
national cost of electricity of $0.076/
kilowatt hours per year (kWh/yr) (U.S.
Department of Energy, Energy
Information Administration (USDOE
EIA) 2002). These calculations are
shown in detail in Chapter 8 of the
Economic Analysis for the Stage 2 DBPR
(USEPA 2003i). The energy use per
plant for each flow range and
technology is then multiplied by the
number of plants predicted to install
each technology in a given flow range.
The energy requirements for each flow
range are then added to produce a
national total. No electricity use is
subtracted to account for the
technologies that may be replaced by
new technologies, resulting in a
conservative estimate of the increase in
energy use. Table VIII-3 shows the
estimated energy use for each Stage 2
DBPR compliance technology in
kilowatt hours per year (kWh/yr). The
incremental national annual energy
usage is 0.08 million megawatt-hours
(mWh).
Table VIII-3. Total Increased Annual National Energy Usage Attributable to the Stage 2 DBPR
Technology
Chloramines (with and without advanced tech.)
Chlorine Dioxide
UV
Ozone
MF/UF
GAC10
GAC10 + Adv. Disinfectants
GAC20
GAC20 + Adv. Disinfectants
NF
Membranes
TOTAL
Number of Plants
Selecting the
Technology
(a)
1,719
9
736
19
0
-
18
113
34
-
17
2,667
Total Increase in
Energy Usage as a
Result of the Stage 2
DBPR
(b)
2,610,918
37,335
11,033,906
1,545,741
1,821
-
H.914,955
24,049,135
4,366,613
-
17,680,345
76,240,768
Notes: Detail may not add due to independent rounding
To determine if the additional energy
required for systems to comply with the
rule would have a significant adverse
effect on the use of energy, the numbers
in Table VIII-3 are compared to the
national production figures for
electricity. According to the U.S.
Department of Energy's Information
Administration, electricity producers
generated 3,800 milHon mWh of
electricity in 2001 (USDOE EIA 2002).
Therefore, even using the highest
assumed energy use for the Stage 2
DBPR, the rule when fully implemented
would result in only a 0.002 percent
increase in annual average energy use.
In addition to average energy use, the
impact at times of peak power demand
is important. To examine whether
increased energy usage might
significantly affect the capacity margins
of energy suppliers, their peak season
generating capacity reserve was
compared to an estimate of peak
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49657
incremental power demand by water
utilities.
Both energy use and water use peak
in the summer months, so the most
significant effects on supply would be
seen then. In the summer of 2001, U.S.
generation capacity exceeded
consumption by 15 percent, or
approximately 120,000 mW (USDOE
EIA 2002). Assuming around-the-clock
operation of water treatment plants, the
total energy requirement can be divided
by 8,760 hours per year to obtain an
average power demand of 8.3 mW. A
more detailed derivation of this value is
shown in Chapter 8 of the Economic
Analysis for the Stage 2 DBPR (USEPA
2003i). Assuming that power demand is
proportional to water flow through the
plant and that peak flow can be as high
as twice the average daily flow during
the summer months, about 16.6 mW
could be needed for treatment
technologies installed to comply with
the Stage 2 DBPR. This is only 0.014
percent of the capacity margin available
at peak use.
Although EPA recognizes that not all
areas have a 15 percent capacity margin
and that this margin varies across
regions and through time, this analysis
reflects the effect of the rule on national
energy supply, distribution, and use.
While certain areas, notably California,
have experienced shortfalls in
generating capacity in the recent past, a
peak incremental power requirement of
16.6 mW nationwide is not likely to
significantly change the energy supply,
distribution, or use in any given area.
Considering this analysis, EPA has
concluded that Stage 2 DBPR will not
nave any significant effort on the use of
anergy, based on annual average use and
an conditions of peak power demand.
f. National Technology Transfer and
Advancement Act
Section 12(d) of the National
rechnology Transfer and Advancement
^\ct (NTTAA) of 1995, Pub. L. No. 104-
113,12(d) (15 U.S.C. 272 note) directs
EPA to use voluntary consensus
standards in its regulatory activities
jnless to do so would be inconsistent
with applicable law or otherwise
impractical. Voluntary consensus
;tandards are technical standards (e.g.,
materials specifications, test methods,
sampling procedures, and business
^radices) that are developed or adopted
jy voluntary consensus standard bodies.
Fhe NTTAA directs EPA to provide
Congress, through OMB, explanations
Arhen the Agency decides not to use
ivailable and applicable voluntary
;onsensus standards.
This proposed rulemaking involves
echnical standards. EPA proposes to
use American Society for Testing and
Materials (ASTM) Method D 6581-00
for chlorite, bromide, and bromate
compliance monitoring, which can be
found in the Annual Book of ASTM
Standards Volume 11.01. In the Stage 1
DBPR, EPA approved 13 methods from
the Standard Methods Committee for
measuring disinfectants, DBFs, and
other parameters. Today's rule proposes
to add the most recent versions of these
13 methods as approved methods. These
consist of Standard Methods 4500-C1 D,
4500-C1 F, 4500-C1 G, 4500-C1 E, 4500-
Cl I, 4500-C1 H, 4500-CIO2 D, 4500-
C1O2 E, 6251 B, 5310 B, 5310 C, 5310
D, and 5910 B for chlorine, chlorine
dioxide, HAAS, chlorite, TOC/DOC, and
UV254- These methods can be found in
the 19th and 20th editions of Standard
Methods for the Examination of Water
and Waste Water (APHA 1995; APHA
1996; APHA 1998). Standard Methods
4500-C1 D, 4500-C1 F, 4500-C1 G, 4500-
Cl E, 4500-C11, 4500-C1 H, 4500-C1O2
E, 6251 B, 5310 B, 5310 C, 5310 D, and
5910 B for chlorine, chlorine dioxide,
HAAS, chlorite, TOC/DOC, and UV254
are also available in the On-Line
Version of Standard Methods for the
Examination of Water and Waste Water
(APHA 2003).
EPA welcomes comments on this
aspect of the proposed rulemaking and,
specifically, invites the public to
identify potentially applicable voluntary
consensus standards and to explain why
such standards should be used in this
regulation.
/. Executive Order 12898: Federal
Actions to Address Environmental
Justice in Minority Populations or Low
Income Populations
Executive Order 12898 establishes a
Federal policy for incorporating
environmental justice into Federal
agency missions by directing agencies to
identify and address disproportionately
high and adverse human health or
environmental effects of its programs,
policies, and activities on minority and
low-income populations. The Agency
has considered environmental justice
related issues concerning the potential
impacts of this action and consulted
with minority and low-income
stakeholders.
Two aspects of the Stage 2 DBPR
comply with the order that requires the
Agency to consider environmental
justice issues in the rulemaking and to
consult with stakeholders representing a
variety of economic and ethnic
backgrounds. These are: (1) The overall
nature of the rule, and (2) the convening
of a stakeholder meeting specifically to
address environmental justice issues.
The Stage 1 DBPR has served as a
template for the development of the
Stage 2 DBPR. As such, the Agency built
on the efforts conducted during the
development of the Stage 1 DBPR to
comply with Executive Order 12898. On
March 12,1998, the Agency held a
stakeholder meeting to address various
components of pending drinking water
regulations and how they might impact
sensitive subpopulations, minority
populations, and low-income
populations. This meeting was a
continuation of stakeholder meetings
that started in 1995 to obtain input on
the Agency's Drinking Water Programs.
Topics discussed included treatment
techniques, costs and benefits, data
quality, health effects, and the
regulatory process. Participants were
national, State, Tribal, municipal, and
individual stakeholders. EPA conducted
the meeting by video conference call
between eleven cities. The major
objectives for the March 12,1998,
meeting were the following:
• Solicit ideas from stakeholders on
known issues concerning current
drinking water regulatory efforts;
• Identify key areas of concern to
stakeholders; and
• Receive suggestions from
stakeholders concerning ways to
increase representation of communities
in OGWDW regulatory efforts.
In addition, EPA developed a plain-
English guide for this meeting to assist
stakeholders in understanding the
multiple and sometimes complex issues
surrounding drinking water regulations.
The Stage 2 DBPR and other drinking
water regulations promulgated or under
development are expected to have a
positive effect on human health
regardless of the social or economic
status of a specific population. The
Stage 2 DBPR serves to provide a similar
level of drinking water protection to all
groups. Where water systems have high
DBF levels, they must reduce levels to
meet the MCLs. Thus, the Stage 2 DBPR
meets the intent of Federal policy
requiring incorporation of
environmental justice into Federal
agency missions.
The Stage 2 DBPR applies uniformly
to community water systems and
nontransient noncommunity water
systems that apply a chemical
disinfectant or deliver water that has
been chemically disinfected.
Consequently, the health protection
from DBF exposure that this rule
provides is equal across all income and
minority groups served by systems
regulated by this rule.
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K. Consultations with the Science
Advisory Board, National Drinking
Water Advisory Council, and the
Secretary of Health and Human Services
In accordance with sections 1412 (d)
and (e) of SDWA, the Agency has
consulted with the Science Advisory
Board (SAB), the National Drinking
Water Advisory Council (NDWAC), and
will consult with the Secretary of Health
and Human Services regarding the
proposed Stage 2 DBPR during the
public comment period.
EPA met with the SAB to discuss the
Stage 2 DBPR on June 13, 2001
(Washington, DC), September 25-26,
2001 (teleconference), and December
10-12, 2001 (Los Angeles, CA). Written
comments from the December 2001
meeting of the SAB addressing the
occurrence analysis and risk assessment
were generally supportive. EPA met
with the NDWAC on November 8, 2001,
in Washington, DC to discuss the Stage
2 DBPR proposal. The Advisory
Committee generally supported the need
for the Stage 2 DBPR based on health
and occurrence data, but also stressed
the importance of providing flexibility
to the systems implementing the rule.
The results of these discussions are
included in the docket for this rule.
L. Plain Language
Executive Order 12866 encourages
Federal agencies to write rules in plain
language. EPA invites comments on
how to make this proposed rule easier
to understand. For example: Has EPA
organized the material to suit
commenters' needs? Are the
requirements in the rule clearly stated?
Does the rule contain technical language
or jargon that is not clear? Would a
different format (grouping and ordering
of sections, use of headings, paragraphs)
make the rule easier to understand?
Could EPA improve clarity by adding
tables, lists, or diagrams? What else
could EPA do to make the rule easier to
understand?
IX. References
Acharya, S., K. Mehta, S. Rodrigues, ].
Pereira, S. Krishman and C.V. Rao. 1995.
Administration of Siibtoxic Doses of T-
butyl Alcohol and Trichloroacetic Acid to
Male Wistar Rats to Study the Interactive
Toxicity. Toxicol. Lett. 80: 97-104.
Acharya, S., K. Mehta, S. Rodrigues, J.
Pereira, S. Krishman and C.V. Rao. 1997.
A Histopathological Study of Liver and
Kidney in Male Wistar Rats Treated with
Subtoxic Doses of T-butyl Alcohol and
Trichloroacetic Acid. Exp. Toxicol. Pathol.
49: 369-373.
American Cancer Society. 2002. Cancer Facts
and Figures, http://www.cancer.org/
downloads/STT/
CancerFacts&Figures2002 TM.pdf.
APHA 1995. Nineteenth Edition of Standard
Methods for the Examination of Water and
Wastewater, American Public Health
Association, 1015 Fifteenth Street, NW.,
Washington, DC 20005.
APHA 1996. Supplement to the Nineteenth
Edition of Standard Methods for the
Examination of Water and Wastewater,
American Public Health Association, 1015
Fifteenth Street, NW., Washington, DC
20005.
APHA 1998. Twentieth Edition of Standard
Methods for the Examination of Water and
Wastewater, American Public Health
Association, 1015 Fifteenth Street, NW.,
Washington, DC 20005.
APHA 2003. On-Line Version of Standard
Methods for the Examination of Water and
Wastewater, American Public Health
Association, 1015 Fifteenth Street, NW.,
Washington, DC 20005.
Aschengrau, A., Zierler S. and Cohen A.
1989. Quality of Community Drinking
Water and the Occurrence of Spontaneous
Abortions. Arch. Environ. Health. 44:283-
90.
Aschengrau, A, Zierler S. and Cohen A. 1993.
Quality of Community Drinking Water and
the Occurrence of Late Adverse Pregnancy
Outcomes. Arch. Environ. Health. 48:105-
113.
ASTM 2002. Method D 6581-00. Annual
Book of ASTM Standards. Vol. 11.01,
American Society for Testing and
Materials.
Balster, R.L., and J.F. Borzelleca, 1982.
Behavioral Toxicology of Trihalomethane
Contaminants of Drinking Water in Mice.
Environmental Health Perspectives. 46,
127-136.
Baribeau, H., S.W. Krasner, R., Chin, R., and
P.C. Singer. 2000. Impact of Biomass on the
Stability of Haloacetic Acids and
Trihalomethanes in a Simulated
Distribution System. Proc. Of the Water
Quality Technology Conference, Denver,
CO. AWWA.
Bhat, H.K., M.F. Kanz, G.A. Campbell and
G.A.S. Ansari. 1991. Ninety Day Toxicity
Study of Chloroacetic Acids in Rats.
Fundam. Appl. Toxicol. 17:240-253.
Biehneier, S.R., D.S. Best, D.L. Guidici, and
M.G. Narotsky. 2001. Pregnancy Loss in the
Rat Caused by Bromodochloromethane.
Toxicol Sci. Feb; 59(2):309-15.
Bolyard, M..G. and M.B. Stricklen. 1992.
Expression of a modified Dutch elm
disease toxin in Escherichia coli. Mol Plant
Microb Interact 1992. 5(6):520-4.
Bove, F.J., M.C. Fulcomer, J.B. Koltz, J.
Esmart, E.M. Dufficy, R.T. Zagraniski and
J.E, Savrin. 1992. Report on Phase IV-B;
Public Drinking Water Contamination and
Birthweight and Selected and Birth
Defects, a Case-Control Study. New Jersey
Dept. of Health.
Bove, F.J. et al. 1995. Public Drinking Water
Contamination and Birth Outcomes. Amer.
J. Epidemiol., 141{9), 850-862.
Bove, F.J.; Shim, Y.; and Zeitz, P. 2002.
Drinking Water Contaminants and Adverse
Pregnancy Outcomes: A Review.
Environmental Health Perspectives
110(Suppl. l):61-74.
Bull, R.J.; I.M. Sanchez, M.A. Nelson, J.L.
Larson and A.J. Lansing. 1990. Liver
Tumor Induction is B6C3F1 Mice by
Dichloroacetate and Trichloracetate.
Toxicology. 63: 341-359.
Cantor, K.P., C.F. Lunch, M. Hildesheim, M.
Dosemeci, J. Lubin, M. Alavanja, G.F.
Craun. 1998. Drinking Water Source and
Chlorination Byproducts. I. Risk of Bladder
Cancer. Epidemiology; 9(l):21-28.
Cantor KP. Lynch CF, Hildesheim ME,
Dosemeci M, Lubin J, Alavanja M, Craun
G., 1999. Drinking Water Source and
Chlorination Byproducts in Iowa. HI. Risk
of Brain Cancer. Am J Epidemiol.
150(6):552-60.
Chang, L.W., F. B. Daniel and A. B.
DeAngelo. 1991. Analysis of DNA Strand
Breaks Induced in Rodent Liver in vivo,
Hepatocytes in Primary Culture, and a
Human Cell Line by Chloroacetic Acids
and Chloroacetaldehydes. Environ. Molec.
Mutagen, 20:277-288.
Chlorine Institute 1999. Bromate in Sodium
Hypochlorite solutions.
Chlorine Institute 2000. Bromate in Sodium
Hypochlorite.
Christian, M.S., R.G. York, A.M. Hoberman,
R.M. Diener, and L.C. Fisher. 2001. Oral
(Drinking Water) Developmental Toxicity
Studies of Bromodichloromethane (BDCM)
in Rats and Rabbits. International Journal
of Toxicology 20(4):225-237.
Christian M.S., York R.G., Hoberman A.M.,
Frazee, L.C., Fisher L.C., Brown W.R., and
D.M. Creasy. 2002a. Oral (drinking water)
Two Generation Reproductive Toxicity
Study of Dibromoacetic Acid (DBA) in
Rats. International Journal of Toxicology
21(4) 237-76.
Christian M.S., York R.G., Hoberman A.M.,
Diener R.M., Fisher L.C. 2002b. Oral
(drinking water) Two Generation
Reproductive Toxicity Study of
Bromodichloromethane (BDCM) in Rats.
International Journal of Toxicology 21
(2):115-146.
Cosby, N. C. and W. R. Dukelow. 1992.
Toxicology of Maternally Ingested
Trichloroethylene (TCE) on Embryonal and
Fetal Development in Mice and of TCE
Metabolites on in vitro Fertilization.
Fundam. Appl. Toxicol. 19(2): 268-74.
Day, J.A., Vonderheide, A.P., and Caruso, J.A.
Second Laboratory Validation of U.S. EPA
Method 321.8: Determination of Bromate in
Drinking Waters by Ion Chromatography
Inductively Coupled Plasma Mass
Spectrometry. University of Cincinnati,
January 2001.
D.C. Circuit 2000. Chlorine Chemistry
Council and Chemical Manufacturers
Association v. EPA, 206 F.3d 1286.
DeAngelo, A.B., F.B. Daniel, L. McMillan, P.
Wernsing and R. E. Savage. 1989. Species
and Strain Sensitivity to the Induction of
Peroxisome Proliferation by Chloroacetic
Acids. Toxicol. Appl. Pharmacol. 101:285-
289.
DeAngelo, A.B., F.B. Daniel, B.M. Most and
G.R. Olson. 1997. Failure of
Monochloroacetic Acid and
Trichloroacetic Acid Administered in the
Drinking Water to Produce Liver Cancer in
Male F344/N rats. J. of Toxicol. and
Environ. Health. 52:425-445.
DeAngelo, A.B., M.H. George and D.E. House.
1999. Hepatocarcinogenicity in the Male
-------
Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
49659
B6C3F1 Mouse Following a Lifetime
Exposure to Dichloroacetic Acid in the
Drinking Water: Dose-Response
Determination and Modes of Action. J.
Toxicol. Environ Health. 58(8):485-507.
)eAngelo, A.B.,.GeterD.R., RosenbergD.W.,
Crary C.K., George M.H. 2002. The
induction of aberrant crypt foci (ACF) in
the colons of rats by trihalomethanes
administered in the drinking water. Cancer
Letters 187(l-2):25-31.
tees, C. and C. Travis. 1994. Trichloroacetate
Stimulation of Liver DNA Synthesis in
Male and Female Mice. Toxicol. Lett,
70:343-355.
)eMarini, D.M., E. Perry and M.L. Sheldon.
1994. Dichloroacetic Acid and Related
Compounds: Induction of Prophage in E.
coli and Mutagenicity and Mutation
Spectra in Salmonella TA 100.
Mutagenesis. 9:429-437.
)odds, L., W. King, C. Wolcott and ]. Pole.
1999. Trihalomethanes in Public Water
Supplies and Adverse Birth Outcomes.
Epidemiology. 10:233-237.
)odds, L. and W.D. King. 2001. Relation
Between Trihalomethane Compounds and
Birth Defects. Occup Environ Med.,
58{7):443-46.
)oyle, Timothy J; Zheng, Wei; Cerhan, James
R; Hong, Ching-Ping. 1997. The association
of drinking water source and chlorination
by-products with cancer incidence among
postmenopausal women in Iowa: A
prospective cohort study. American
Journal of Public Health, 87(7):1168-1176.
"air, P.S. Memo to the record. February 2002.
^air, P.S., R.K. Sorrell, M. Stultz-Karapondo,
et al., 2002. Quality of Information
Collection Rule Monitoring Data. In
Information Collection Rule Data Analysis,
M.J. McGuire, J. McLain, and A. Obolensky
(eds), AwwaRF, Denver, CO.
''erreira-Gonzalez, A., A.B. DeAngelo, S.
Nasim and C.T. Garrett. 1995. Ras
Oncogene Activation during
Hepatocarcinogenesis in B6C3F1 Male
Mice by Dichloroacetic and Trichloroacetic
Acids. Carcinogenesis. 16(3):495-500.
i'ort, D., E. Stover, J. Rayburn, M. Hull and
J. Bantle. 1993. Evaluation of the
Developmental Toxicity of
Trichloroethylene and Detoxification
Metabolites using Xenopus. Teratogenesis,
Carcinogenesis, and Mutagenesis. 13:35-
45.
"U, L., E.M. Johnson and L.M. Newman.
1990. Prediction of the Developmental
Toxicity Hazard Potential of Halogenated
Drinking Water Disinfection By-products
Tested by the in vitro Hydra Assay. Reg.
Toxicol. and Pharmacol. 11:213-219.
Gallagher, M.D., J.R. Nuckols, L. Stallones
and D.A. Savitz. 1998. Exposure to
Trihalomethanes and Adverse Pregnancy
Outcomes. Epidemiology. 9:484-489.
;erba, C.P., J.B. Rose and C.N. Haas. 1996.
Sensitive Populations: Who is at the
Greatest Risk. Int. J. Food and
Microbiology. 30:113-123.
;iller, S., F. Le Curieux, F. Erb and D.
Marzin. 1997. Comparative Genotoxicity of
Halogenated Acetic Acids Found in
Drinking Water. Mutagenesis. 12(5):321-
328.
oldsworthy, T.L. and J.A. Popp. 1987.
Chlorinated Hydrocarbon-Induced
Peroxisomal Enzyme Activity in Relation
to Species and Organ Carcinogenicity.
Toxicol. Appl. Pharmacol. 88:225-233.
Harrington-Brock, K. C.L. Doerr and M.M.
Moore. 1998. Mutagenicity of Three
disinfection by-products; di- and
trichloroacetic acid and chloral hydrate in
L5178Y/TK+/ - 3.7.2C mouse lymphoma
cells. Mutation Research. 413:265-276.
Hautman, D.P., Munch, D.J., Frebis, C.P.,
Wagner, H.P., and Pepich, B.V. 2001.
Review of the Methods of the U.S.
Environmental Protection Agency for
Bromate Determination and Validation of
Method 317.0 for Disinfection By-Product
Anions and Low-Level Bromate. Journal of
Chromatography A, 920 (2001) 221-229.
Heywood, R., R.J. Sortwell, P.R.B. Noel, A.E.
Street, D.E. Prentice, F.J.C. Roe, P.F.
Wadsworth, A.N. Worden, N.J. Van Abbe.
1979. Safety Evaluation of Toothpaste
Containing Chloroform. III. Long-term
Study in Beagle Dogs. J. Environ. Pathol.
Toxicol. 2:835-851.
Hildesheim, M.E., K.P. Cantor, C.F. Lynch,
M. Dosemeci, J. Lubin, M. Alavanja, and
G.F. Craun. 1998. Drinking Water Source
and Chlorination Byproducts: Risk of
Colon and Rectal Cancers. Epidemiology.
9(l):29-35.
Hooper and Allgeier, 2002. Information
Collection Rule Treatment Studies.
AwwaRF.
Hrubek Z. and J.K. McLaughlin. 1997.
"Former cigarette smoking and mortality
among U.S. veterans: a 26-year follow-up."
In: Changes in cigarette related disease
risks and their implication for prevention
and control. D.M. Burns, L. Garfinkel, J.M.
Samet (eds.). NIH Monograph No. 8,
National Institutes of Health. Washington,
DC: National Cancer Institute, pp.501-530.
Hunter, III, E.S., E.H. Rogers, J.E. Schmid and
A. Richard. 1996. Comparative Effects of
Haloacetic Acids in Whole Embryo
Culture. Teratology. 54:57-64.
Hwang, B-, P. Magnus, and J.K. Jaakkola,
2002. Risk of Specific Birth Defects in
Relation to Chlorination and the Amount
of Natural Organic Matter in the Water
Supply. Am J Epidemiol 2002; 156:374-
382.
ILSI1998, International Life Sciences
Institute. Exposure to Contaminants in
Drinking Water Estimating Uptake through
the Skin and by Inhalation.
Infante-Rivard, C., E. Olson, L. Jacques and
P. Ayotte. 2001. Drinking Water
Contaminants and Childhood Leukemia.
Epidemiology 12(l):13-19.
IRIS 1991. Integrated Risk Information
System (IRIS). N-nitrosodimethylamine
(NDMA). Washington, DC: U. S.
Environmental Protection Agency, http://
www.epa.gov/iiis/subst/0045.httn
IRIS 2001. Integrated Risk Information
System (IRIS). Chloroform. Washington,
DC: U. S. Environmental Protection
Agency, http://www.epa.gov/iris/subst/
0025.htm
Jaakkola JJK, Magnus P, Skrondal A, Hwang
B-F, Becher G, Dybing E. 2001. Foetal
growth and duration of gestation relative to
water chlorination. Occup Environ Med
58:437-142.
Ji, Y., C. Qin-Yao, W. Xiao-fei, L. Yi and L.
Hong-mei. 1998. Prescreening Teratogenic
Potential of Chlorinated Drinking Water
Disinfection By-products by using Hydra
Regeneration Assay. J. of Environ.
Sciences. 10(1):110-112.
Johnson, P.D., B.V. Dawson, and S.J.
Goldberg. 1998. Cardiac Teratogenicity of
Trichloroethylene Metabolites. J. American
College of Cardiology. 32(2):540-545.
Kallen, B.A.J .and E. Robert. 2000. Drinking
water Chlorination and Delivery
Outcome—a Registry Based Study in
Sweden. Reprod. Toxicol. 14:303-309.
Kanitz S, Franco Y, Patrone V, Caltabellotta
M, Raffo E, Riggi C, Timitilli D, Ravera G.
1996, Association between drinking water
disinfection and somatic parameters al
birth. Environ Health Perspect 104(5):516-
520.
Kim, H. and C. P. Weisel. 1998. Dermal
Absorption of Dichloro- and
Trichloroacetic Acids from Chlorinated
Water. J. of Exposure Anal, and Environ.
Epidem. 8(4):555-575.
King, W., L. Dodds and A. Allen. 2000a.
Relation between Stillbirth and Specific
Chlorination By-products in Public Water
Supplies. Environ. Health
Perspect. 108:883-8 86.
King, W.D., L.D. Marrett and C.G. Woolcott.
2000b. Case-Control Study of Colon and
Rectal Cancers and Chlorination By-
products in Treated Water. Cancer
Epidemiology, Biomarkers & Prevention
9:813-818.
Klinefelter, G.R., Hunter, E.S., and Narotsky,
M. 2001. Reproductive and Developmental
Toxicity Associated with Disinfection By-
Products of Drinking Water, In: Microbial
Pathogens and Disinfection By-Products of
Drinking Water, ILSI Press, 309-323.
Klotz J.B. and L.A. Pyrch, 1998. A Case
Control Study of Neural Tube Defects and
Drinking Water Contaminants. U.S.
Department of Health and Human Services,
Agency for Toxic Substances and Disease
Registry (ATSDR).
Klotz, J.B. and L.A. Pyrch, 1999. Neural Tube
Defects and Drinking Water Disinfection
Byproducts. Epidemiology 10:383-390.
Koivusalo M, T. Hakulinen, T. Vartiainen, &t
al., 1998. Drinking Water Mutagenicity and
Urinary Tract Cancers: a Population-Based
Case-Control Study in Finland. American
Journal of Epidemiology 148(7):704-12.
Kramer M.D., C.F. Lynch, P. Isacson, J.W.
Hanson, 1992. The Association of
Waterborne Chloroform with Intrauterine
Growth Retardation. Epidemiology 3:407-
413.
Krasner, S.W., Sclimenti, M.J., and Hwang,
C.J. 1989. Experiences with Implementing
a Laboratory Program to Sample and
Analyze for Disinfection By-Products in a
National Study. In Disinfection By-
Products: Current Perspectives, AWWA,
Denver, CO.
Latendresse, J.R. and M.A. Pereira. 1997.
Dissimilar Characteristics of N-methyl-N-
nitrosourea-initiated Foci and Tumors
Promoted by Dichloroacetic Acid or
Trichloroacetic Acid in the Liver of Female
B6C3F1 Mice. Toxicol. Pathol. 25(5): 433-
440.
Linder, R.E., G.R. Klinefelter, L.F. Strader,
J.D. Suarez, and C.J. Dyer. 1994a. Acute
Spermatogenic Effects of Bromoacetic
-------
49660
Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
Acids. Fundamental and Applied
Toxicology. 22: 422-430.
Under, R.E., G.R. Klinefelter, L.F. Strader,
J.D. Suarez, N.L. Roberts, and C.J. Dyer.
1994b. Spermatotoxicity of Dibromoacetic
Acid in Rats after 14 Daily Exposures.
Reproductive Toxicology. 8(3): 251-259.
Linder, R.E., G.R. Klinefelter, L.F. Strader,
M.G. Narotsky, J.D. Suarez, N.L. Roberts
and S.D. Perreault. 1995. Dibromoacetic
Acid Affects Reproductive Competence
and Sperm Quality in the Male Rat.
Fundamental and Applied Toxicology. 28:
9-17.
Linder, R.E., G.R. Klinefelter, L.F. Strader,
J.D. Suarez, and N.L. Roberts. 1997a.
Spermatotoxicity of Dichloroacetic Acid.
Reproductive Toxicology. 11(5): 681-688.
Linder, R.E., G.R. Klinefelter, L.F. Strader,
D.N. Veeramachaneni, N.L. Roberts and
J.D. Suarez, 1997b. Histopathologic
Changes in the Testes of Rats Exposed to
Dibromoacetic Acid. Reprod. Toxicol.
11(1), 47-56.
Mackay, J.M., V. Fox, K. Griffiths, D.A. Fox,
C.A. Howard, C. Coutts, I. Wyatt and J.A.
Styles. 1995. Trichloroacetic Acid:
Investigation into the Mechanism of
Chromosomal Damage in the j'n vitro
Human Lymphocyte Cytogenetic Assay
and the Mouse Bone Marrow Micronucleus
Test. Carcinogenesis. 16(5): 1127-1133.
Magat, W.A., W.K. Viscusi, and J. Huber.
1996. "A Reference Lottery Metric for
Valuing Health." Management Science
42:1118-1130.
Magnus, P., J.J.K. Jaakkola, A. Skrondal, J.
Alexander, G. Becher, T. Krogh and E.
Dybing. 1999. Water Chlorination and
Birth Defects. Epidemiology. 10:513-517.
Malley, J., J. Show, and J. Ropp. 1996.
Evaluation of the by-products produced by
the treatment of groundwaters with
ultraviolet radiation. American Water
Works Association Research Foundation,
Denver, CO.
Mather, G.G, J.H. Exon and L.D. Koller. 1990.
Subchronic 90-day Toxicity of
Dichloroacetic and Trichloroacetic Acid in
Rats, Toxicology 64: 71-80.
Murray, F.J., B.A. Schwetz, J.G. McBride, and
R.E. Staples, 1979. Toxicity of Inhaled
Chloroform in Pregnant Mice and Their
Offspring. Toxicol. Appl. Pharmacol. 50(3),
515-522.
Narotsky, M.G., and R.). Kavlock. 1992.
Effects of Bromoform and
Bromodichloromethane in an in vivo
Developmental Toxicity Screen. EPA
report to Office of Water.
Narotsky, M.G., B.T. Hamby, and D.S. Best,
1997a. Developmental Effects of
Dibromoacetic Acid (DBA) in a Segment II
Study in Mice. Teratology 55 (1), 67.
Narotsky, M.G., R.A. Pegram, and R.J.
Kavlock. 1997b. Effect of dosing Vehicle on
the Developmental Toxicity of
Bromodichlomethane and Carbon
Tetrachloride in Rats. Fundamental and
Applied Tox. 40:30-36.
NATICH 1993. National Air Toxics
Information Clearinghouse. Acceptable
ambient concentration guidelines or
standards by pollutants: Trichloroacetic
acid. Washington, DC: U.S. Environmental
Protection Agency, Office of Air Quality
Planning and Standards. April 22,1993.
Nelson, M.A. and R. J. Bull. 1988. Induction
of Strand Breaks in DNA by
Trichloroethylene and Metabolites in Rat
and Mouse livers in vivo. Toxicol. Appl.
Pharmacol. 94:45-54.
Nieuwenhuijsen, M.J., M.B. Toledano, N.E.
Eaton, J. Fawell and P. Elliott, 2000.
Chlorination Disinfection By-products in
Water and Their Association with Adverse
Reproductive Outcomes: A Review. Occup.
Environ. Med., 57(2):73-85.
NOAA 1998. Palmer Drought Severity Index
Maps http://www.cpc.noaa.gov/products/
monitoring_and_data/drough t.html.
NTP 1987. National Toxicology Program.
Toxicity and carcinogenesis studies of
bromodichloromethane (CAS No. 75-27-4)
in F344/N rats and B6C3F1 mice (gavage
studies). Technical Report Series No. 321.
Research Triangle Park, NC: U.S.
Department of Health and Human Services.
NTP 1989. Toxicology and carcinogenesis
studies of tribromomethane (bromoform) in
F344/N rats and B6C3F1 mice {gavage
studies). Technical Report Series No. 350.
Research Triangle Park, NC: U.S.
Department of Health and Human Services.
NTP 3992. NTP technical Report on the
Toxicology and Carcinogenesis Studies of
Monochloroacetic Acid (CAS No. 79-11-8)
in F344/N rats and B6C3F1 Mice (Gavage
Studies). NTP TR 396. NT1S Publication
No. PB92-1B9372.
OSTP 1985. Chemical Carcinogens; A Review
of the Science and Its Associated
Principles, February 1985. Presented in
Risk Analysis: A guide to Principles and
Methods for Analyzing Health and
Environmental Risks. Appendix G. Fed.
Reg., Pages 10371-10442. (March 14,
1985).
Overbeck, P.K. 2000. WQA Ozone Task
Force—An Update. Water Conditioning
and Purification. 42(3) 76-78.
Parrish, J.M., E.W. Austin, O.K. Stevens, D.H.
Kinder and R.J. Bull. 1996. Haloacetate-
Induced Oxidative Damage to DNA in the
Liver of Male B6C3F1 Mice. Toxicology.
110:103-111.
Pawlecki-Vonderheide, A.M., Munch, D.J.,
and Munch, J.W. 1997. Research
Associated with the Development of EPA
Method 552.2. J. of Chromatographic
Science. 35:293-301.
Pereira, M. A. 1996. Carcinogenic Activity of
Dichloroacetic Acid and Trichloroacetic
Acid in the Liver of Female B6C3F1 Mice.
Fundam. Appl. Toxicol. 31:192-199.
Pereira, M.A. and J.B. Phelps. 1996.
Promotion by Dichloroacetic Acid and
Trichloroacetic Acid of N-methyl-N-
nitrosourea-initiated cancer in the Liver of
Female B6C3F1 Mice. Cancer Lett.
102:133-141.
Personal communication from M. Kogevinas
to M. Messner, 5/19/2003.
Raymer, J.H., Pellizzari, E.D., Hu, Y. et a!.
(2001). Assessment of Human Dietary
Ingestion Exposures to Water Disinfection
Byproducts via Food. Star Drinking Water
Progress Review Meeting, February 22-23,
2001, Silver Spring, MD.
Reif, J.S., A. Bachand and M. Andersen.
2000. Reproductive and Developmental
Effects of Disinfection By-Products. Bureau
of Reproductive and Child Health, Health
Canada, Ottawa, Ontario, Canada.
Executive summary available at http://
wwwJic-sc.gc.ca/pphb-dgspsp/pubIicat/
reif/indfix.html.
Reimann, S., K. Grab and H. Frank. 1996.
Environmental chloroacetic acids in foods
analyzed by GC-ECD. Mitteilungen Aus
Dem Gebiete der
Lebensmitteluntersuchung und Hygiene.
87 (2):212-222.
Rice, 2000—personal communication: e-mail
7/14/2000.
Ruddick, J.A., D.C. Villeneuve, and I. Chu,
1983. A Teratological Assessment of Four
Trihalomethanes in the Rat. J. Environ. Sci.
Health B18(3), 333-349.
Saillenfait, A. M., I. Langonne and J. P.
Sabate. 1995. Developmental Toxicity of
Trichloroethylene, Tetrachloroethylene
and Four of Their Metabolites in Rat Whole
Embryo Culture. Arch. Toxicol. 70:71-82.
Salhi, E. and von Gunten, U. 1999.
Simultaneous Determination of Bromide,
Bromate and Nitrite in Low jig 1-' Levels by
Ion Chromatography without Sample
Pretreatment. Water Research. 33
(15):3239-3244.
Sanchez, I. M. and R. J. Bull. 1990. Early
Induction of Reparative Hyperplasia in
B6C3Fi Mice Treated with Dichloroacetate
and Trichloroacetate. Toxicology. 64:33-
46.
Savitz, D. A., K.W. Andrews and L. M.
Pastore. 1995. Drinking Water and
Pregnancy Outcome in Central North
Carolina: Source, Amount, and
Trihalomethane levels. Environ. Health
Perspectives. 103(6), 592-596.
Schwetz, B.A., K.J. Leong, and P.J. Gehring,
1974. Embryo- and Fetotoxicity of Inhaled
Chloroform in Rats. Toxicol. Appl.
Pharmacol. 28(3), 442-451.
Seidel, C. 2001. BAT Memorandum on
SWAT Runs for Stage 2 BAT Evaluation.
(June 25, 2001).
Simmons, J.E.; S Richardson, T. Speth, R.
Miltner, G. Rice, K. Schenck, E.S. Hunter
HI, and L. Teuschler. 2002. Development of
a Research Strategy for Integrated
Technology-Based Toxicological and
Chemical Evaluation of Complex Mixtures
of Drinking Water Disinfection Byproducts.
Environmental Health Perspectives Vol.
110 Supplement 6, 1013-1024.
Smith, M.K., J.L. Randall, and J.A. Stober.
1988. Developmental effects of
trichloroacetic acid in Long-Evans rats.
Teratology 37(5), 495.
Smith, M.K., J.L. Randall, E.J. Read and J.A.
Stober. 1989. Teratogenic Effects of
Trichloroacetic Acid in the Rat. Teratology.
40:445-451.
Smith, M.K., J.L. Randall, E.J. Read, and J.A.
Stober. 1990. Developmental effects of
Chloroacetic acid in the Long-Evans Rat.
Teratology 41 (5), 593 (Abstract No. P164).
Smith, V.K., G. Van Houtven and S.K.
Pattanayak. 2002. Benefit transfer via
preference calibration: 'Prudential algebra'
for policy. Land Economics, 78(3):132-152.
Stauber, A.J. and R.J. Bull. 1997. Differences
in Phenotype and Cell Replicative
Behavior of Hepatic Tumors Induced by
Dichloroacetate (DCA) and
Trichloroacetate (TCA). Toxicol. Appl.
Pharmacol. 144(2): 235-46.
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49661
Tao, L., K. Li, P.M. Kramer and
M.A.Perei.l996.Loss of Heterozygosity on
Chromosome 6 in Dichloroacetic Acid and
Trichioroacetic Acid-Induced Liver
Tumors in Female B6C3Fi Mice. Cancer
Lett. 108:257-261.
Tao, L., P.M. Kramer, R. Ge and M.A. Pereira.
1998. Effect of Dichloroacetic Acid and
Trichioroacetic Acid on DNA Methylation
in Liver and Tumors of Female B6C3F(
Mice. Toxicol. Sciences. 43: 1,39-144.
Thompson, D.L., S.D. Warner, and V.B.
Robinson, 1974. Teratology Studies in
Orally Administered Chloroform in the Rat
and Rabbit. Toxicol. Appl. Pharmacol. 29,
348-357.
Toth, G.P., K.C. Kelty, E.L. George, E.J. Read,
and M.K. Smith, 1992. Adverse Male
Reproductive Effects Following Subchronic
Exposure of Rats to Sodium
Dichloroacetate. Fund. Appl. Toxicol. 19,
57-63.
Tyl, R.W. 2000. Review of Animal Studies for
Reproductive and Developmental Toxicity
Assessment of Drinking Water
Contaminants: Disinfection By-Products
(DBFs). RTI Project No. 07639. Research
Triangle Institute.
USDOE Energy Information Administration
2002. Table 7.1 Electricity Overview
(Billion Kilowatthours). http://
www.eia.doe.gov/emeu/mor/txt/nwr7-l
USEPA 1979. National Interim Primary
Drinking Water Regulations; Control of
Trihalomethanes in Drinking Water. FR
44:231:68624. (November 29, 1979).
USEPA 1985. National Primary Drinking
. Water Regulations; Volatile Synthetic
Organic Chemicals; Final Rule and
Proposed Rule. FR 50:219:46880
(September 13,1985).
USEPA 1986. Guidelines for Carcinogen Risk
Assessment, FR 51:185:33992-34003. EPA/
600/8-87/045. NTIS PB88-123997. http://
www.epa.gov/ncea/raf/rafguid.httn
USEPA 1989a. National Primary Drinking
Water Regulations; Filtration, Disinfection,
Turbidity, Giardia lamblia, Viruses,
Legionella, and Heterotrophic Bacteria;
Final Rule. Part II. FR 54:124: 27486. (June
29,1989).
USEPA 1989b. National Primary Drinking
Water Regulations; Total Coliforms
(Including Fecal Coliform and E. coli);
Final Rule. FR 54:124: 27544. [June 29,
1989).
USEPA 1989c. Review of Environmental
Contaminants and Toxicology. U.S. EPA.
Office of Drinking Water Health
Advisories. Volume 106. 225 pp.
USEPA 1991a. National Primary Drinking
Water Regulations; Synthetic Organic
Chemicals and Inorganic Chemicals;
Monitoring for Unregulated Contaminants;
National Primary Drinking Water
Regulations Implementation; National
Secondary Drinking Water Regulations.
Final rule, January 31, 1991. FR 56:20:
3526.
USEPA 1991b. Guidelines for Developmental
Toxicity Risk Assessment. FR
56:234:63798-63826.
USEPA 1992. EPA Method 552.1. In Methods
for the Determination of Organic
Compounds in Drinking Water—
Supplement II. EPA 600/R-92/129. NTIS,
PB92-207703.
USEPA 1993. EPA Method 300.0. In Methods
for the Determination of Inorganic
Substances in Environmental Samples.
EPA/600/R/93/100.
USEPA 1994a. Draft Drinking Water Health
Criteria Document for Chlorinated Acetic
Acids/Alcohols/Aldehydes and Ketones.
Office of Science and Technology, Office of
Water.
USEPA 1994b. National Primary Drinking
Water Regulations; Disinfectants and
Disinfection Byproducts; Proposed Rule.
FR 59:145:38668-38829. (July 29, 1994).
USEPA 1995. EPA Method 552.2. In Methods
for the Determination of Organic
Compounds in Drinking Water.
Supplement III. EPA-600/R-95/131. NTIS,
PB95261616.
USEPA 1996a. National Primary Drinking
Water Regulation: Monitoring
Requirements for Public Drinking Water
Supplies: Cryptosporidium, Giardia,
Viruses, Disinfection Byproducts, Water
Treatment Plant Data and Other
Information Requirements. Final Rule. FR
61:94:24354-24388. (May 14, 1996).
USEPA 1996b. DBP/ICR Analytical Methods
Manual EPA 814-B-96-002. NTIS, PB96-
157516.
USEPA 1997a. National Primary Drinking
Water Regulations; Disinfectants and
Disinfection Byproducts; Notice of Data
Availability; Proposed Rule. FR
62:212:59388-59484. (November 3,1997).
USEPA 1997b. Manual for the Certification of
Laboratories Analyzing Drinking Water,
EPA 815-B-97-001. http://wwH-.epa.gov/
OGWDW/certhb/hbindex.h tml
USEPA 1998a. Quantification of Bladder
Cancer Risk from Exposure to Chlorinated
Surface Water. Office of Science and
Technology, Office of Water. November 9,
1998.
USEPA 1998b. Health Risk Assessment/
Characterization of the Drinking Water
Disinfection Byproduct Chloroform. Office
of Science and Technology, Office of
Water. EPA 815-B-98-006. PB 99-111346.
USEPA 1998c. National Primary Drinking
Water Regulations: Disinfectants and
Disinfection Byproducts; Final Rule. FR
63:241:69390-69476. (December 16, 1998).
h ftp://www.epa .gov/safewater/mdbp/
dbpfr.pdf
USEPA 1998d. National Primary Drinking
Water Regulations: Interim Enhanced
Surface Water Treatment Rule; Final Rule.
FR 63:241:38832-38858. (December 16,
1998). http://www.epa.gov/safewater/
mdbp/ieswtrfr.pdf
USEPA 1998e. National Primary Drinking
Water Regulations; Disinfectants and
Disinfection Byproducts; Notice of Data
Availability; Proposed Rule. FR
63:61:15606-15692. (March 31, 1998).
USEPA 1998f. Regulatory Impact Analysis of
Final Disinfectant/Disinfection By-
Products Regulations- Washington, DC.
EPA Number 815-B-98-002. PB 99-
111304.
USEPA 1998g. National-Level Affordability
Criteria Under the 1996 Ammendments to
the Safe Drinking Water Act (Final Draft
Report). Contact 68-C6-0039. (August 19,
1998).
USEPA 1998h. Variance Technology
Findings for Contaminants Regulated
Before 1996. Office of Water. EPA 815-R-
98-003.
USEPA 1998i. National Primary Drinking
Water Regulations: Consumer Confidence
Reports; Final Rule. FR 63:160:44512-
44536.
USEPA 1998J. Revisions to State Primacy
Requirements to Implement Safe Drinking
Water Act Amendments; Final Rule. FR
63:81:23362-23368.
USEPA 1999a. Guidelines for carcinogen risk
assessment. July SAB Review draft. Office
of Research and Development, Washington,
DC. USEPA NCEA-F-0644. http://
www.epa.gov/ncea/raf/crasab.htm
USEPA 1999b. National Primary and
Secondary Drinking Water Regulations:
Analytical Methods for Chemical and
Microbiological Contaminants and
Revisions to Laboratory Certification
Requirements; Final Rule. FR
64:230:67449. (December 1, 1999).
USEPA 1999c. Chloroform Mode of Action
Analysis. Prepared for the Science
Advisory Board by Office of Science and
Technology, Office of Water. October 1999.
h ttp illwww. epa .gov/sab/chloroOO.htm
USEPA 1999d. Cost of Illness Handbook.
Office of Pollution Prevention and Toxics.
Chapter 1 H.8. Cost of Bladder Cancer.
September, 1999. http://ww\v.epa.gov/
oppt/coi
USEPA 2000a. Estimated per Capita Water
Ingestion in the United States. EPA-
82200-008. http://www.epa.gov/
waterscience/drinking/pcrcapiia/
USEPA 2000b. Guidelines for Preparing
Economic Analyses. Washington, DC. EPA
240R-00-003, September 2000.
USEPA 2000c. Information Collection Rule
Auxiliary 1 Database, Version 5, EPA 815-
C-00-002, April 2000.
USEPA 2000d. EPA Method 321.8. In
Methods for the Determination of Organic
and Inorganic Compounds in Drinking
Water, Volume 1. ORD-NERL, Cincinnati,
OH. EPA 815-R-00-014. Available on
ORD-NERL Web site at http://
www.epa.gov/nerhwww/ordmeth.htm.
USEPA 2000e. Removal of the Maximum
Contaminant Level Goal for Chloroform
From the National Primary Drinking Water
Regulations. FR 65:104:34404-34405. (May
30, 2000). http://www.epa.gov/safewater/
regs/chlorfr.html
USEPA 2000f. Review of the EPA's Draft
Chloroform Risk Assessment by a
Subcommittee of the Science Advisory
Board. Science Advisory Board,
Washington, DC. EPA-SAB-EC-00-009.
USEPA 2000g. Stage 2 Microbial and
Disinfection Byproducts Federal Advisory
Committee Agreement in Principle. FR
65:251:83015-83024. (December 29, 2000).
http://www.epa .gov/fedrgstr/EPA-WA TER/
2000/December/Day-29/w33306.htm
USEPA 2000h. National Primary Drinking
Water Regulations: Ground Water Rule.
Proposed Rules. FR 65:91:30194-30274.
(May 10, 2000).
USEPA 2000i. Quantitative Cancer
Assessment for MX and
Chlorohydroxyfuranones. Contract NO. 68-
C-98-195. August 11, 2000, Office of
Water, Office of Science and Technology,
Health and Ecological Criteria Division,
Washington, DC.
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USEPA 2000J. Drinking Water Baseline
Handbook, Second Edition. Prepared by
International Consultants, Inc. under
contract with EPA OGWDW, Standards
and Risk Management Division. March 17,
2000.
USEPA 2000k. Geometries and
Characteristics of Public Water Systems.
Final Report. EPA 815-R-00-024.
December 2000.
USEPA 20001. EPA Method 300.1. In
Methods for the Determination of Organic
and Inorganic Compounds in Drinking
Water, Volume 1. OW-OGWDW-TSC,
Cincinnati, OH. EPA 815-R-00-014.
Available on the OGWDW Web site at
h ttp://www. epa.gov/safewater/niethods/
sourcalt.html.
USEPA 2000m. Information Collection Rule
Treatment Study Database CD-ROM,
Version 1.0.
USEPA 2000n. Science Advisory Board Final
Report. Prepared for Environmental
Economics Advisory Committee. July 27,
2000. EPA-SAB-EEAC-00-013.
USEPA 20000. Draft Dioxin Reassessment.
EPA/600/P-00/OOlBftttp;//c/pu6.epa.gov/
ncea/cfm/partland2.cfm?ActType=defauit.
USEPA 2001 a. Relative Source Contribution
for Chloroform. EPA-822-R-01-006.
USEPA 2001D. Toxicological Review of
Chloroform. In support of Integrated Risk
Information System (IRIS). Washington,
DC. Draft. EPA/635/R-01/001.
USEPA 2001c. National Primary Drinking
Water Regulations: Filter Backwash
Recycling Rule. Final Rule. FR
66:111:31086-31105. (June 8, 2001).
USEPA 2001d. Method 317.0, Revision 2.0.
Determination of Inorganic Oxyhalide
Disinfection By-Products in Drinking
Water Using Ion Chromatography with the
Addition of a Postcolumn Reagent for
Trace Bromate Analysis. Revision 2.0. EPA
815-B-01-001. (Available on the OGWDW
Web site at http://www.epa.gov/safewater/
methods/sourcalt.html.)
USEPA 2001e. Arsenic Rule Benefits
Analysis: an SAB Review. August 30, 2001.
EPA-SAB-EC-01-008.
USEPA 2002a. Method 326.0. Determination
of Inorganic Oxyhalide Disinfection By-
Products in Drinking Water Using Ion
Chromatography Incorporating the
Addition of a Suppressor Acidified
Postcolumn Reagent for Trace Bromate
Analysis. Revision 1.0. EPA 815-R-03-
007. (Available on the OGWDW Web site
at http://www.epa.gov/safewater/niethods/
sourcalt.html.)
USEPA 2002b. Long Term 1 Enhanced
Surface Water Treatment Rule. January 14,
2002. 67 FR 1812.
USEPA 2002c. Affordability Criteria for
Small Drinking Water Systems: an EPA
Science Advisory Board Report. December
2002. EPA-SAB-EEAC-03-004.
USEPA 2003a. Health Risks to Fetuses,
Infants, and Children: A Review. Office of
Water, Office of Science and Technology,
Health and Ecological Criteria Division.
USEPA 2003b. Addendum to the Criteria
Document for Monochloroacetic Acid and
Trichleoeacetic Acid: External Review
Draft.
USEPA 2003c. Addendum to the Criteria
Document for Dichloroacetic Acid:
External Review Draft.
USEPA 2003d. Drinking Water Criteria
Document for Brominated
Trihalomethanes: External Review Draft.
USEPA 2003e. Drinking Water Criteria
Document for Brominated Haloacetic
Acids: External Review Draft.
USEPA 2003f. Drinking Water Criteria
Document for Cyanogen Chloride, External
Review Draft.
USEPA 2003g. Drinking Water Criteria
Document for Glyoxal and Methylglyoxal:
External Review Draft.
USEPA 2003h. Drinking Water Criteria
Document for Haloacetonitriles: External
Review Draft.
USEPA 2003i. Economic Analysis for the
Proposed Stage 2 DBPR. Washington, DC.
EPA815-D-03-001.
USEPA 2003J, Draft Initial Distribution
System Evaluation Guidance Manual.
Washington, DC. EPA 815-D-03-002.
USEPA 2003k. Technologies and Costs for
Control of Microbial Pathogens and
Disinfection Byproducts. Prepared by the
Cadmus Group and Malcolm Pirnie.
USEPA 20031. Toxicologcal Review for
Dichloroacetic Acid: Consensus Review
Draft, http://www.epa.gov/ins/subst/
0654.htm
USEPA 2003m. Information Collection
Request. Washington, DC. EPA 815-D-03-
003.
USEPA 2003n. Draft Significant Excursion
Guidance Manual. Washington, DC. EPA
815-D-03-004.
USEPA 20030. Stage 2 Occurrence
Assessment for Disinfectants and
Disinfection Byproducts (D/DBPs). EPA
68-C-99-206.
USEPA 2003p. Method 552.3. Determination
of Haloacetic Acids and Dalapon in
Drinking Water by Liquid-liquid
Extraction, Derivatization, and Gas
Chromatography with Electron Capture
Detection. Revision 1.0. (Available on the
OGWDW Web site at http://www.epa.gov/
safewater/methods/sourcait.html.)
USEPA 2003q. Method 327.0. Determination
of Chlorine Dioxide and Chlorite Ion in
Drinking water Using Lissamine Green B
and Horseradish Peroxidase with Detection
by Visible Spectrophotometry. Revision
1.0. (Available on the OGWDW Web site at
h ftp ://www. epa .gov/safewater/methods/
sourcalt.html,)
USEPA 2003r. Method 415.3. Determination
of Total Organic Carbon, and Specific UV
Absorbance at 254 nm in Source Water and
Drinking Water. Revision 1.0. NERL,
Cincinnati, OH 45268.
USEPA 2003s. Arsenic in Drinking Water:
Cessation Lag Model. Prepared by Sciences
International. Contract No. 68-C-98-195.
January, 2003.
Veeramachaneni, D.N.R., T.T. Higuchi, J.S.
Palmer, and C.M. Kane. 2000.
Dibromoacetic Acid, a Disinfection By-
product in Drinking Water, Impairs Sexual
Function and Fertility in Male Rabbits.
Paper presented at the annual meeting for
the Society for the Study of Reproduction,
Madison, Wisconsin.
Vena, JE, Graham, S, Freudenheim, J,
Marshall, J, Zielezny, M, Swanson, M,
Sufrin, G. 1993. Drinking water, fluid
intake, and bladder cancer in western New
York. Archives of Environmental Health,
48(3):191-8.
Ventura, S.J., W.D. Mosher, S.C. Curtin, |.C.
Abma, and S. Henshaw. 2000. "Trends in
Pregnancies and Pregnancy Rates by
Outcome: Estimates for the United States,
1976-96." National Center for Health
Statistics. Vital Health Stat 21(56).
Villanueva, C.M., F. Fernandez, N. Malats,
J.O. Grimalt, M. Kogevinas. 2003. Meta-
analysis of Studies on Individual
Consumption of Chlorinated Drinking
Water and Bladder Cancer. J Epidemiol
Community Health, 57:166-173.
Wagner, H.P., Pepich, B.V., Frebis, C,
Hautman, D.P., Munch, D.J., and Jackson,
P.E. 2001. A Collaborative Study of EPA
Method 317.0 for the Determination of
Inorganic Oxyhalide Disinfection By-
Products in Drinking Water using Ion
Chromatography with the Addition of a
Postcolumn Reagent for Trace Bromate
Analysis. Journal of Chromatographic
Science. Vol 39 (255-259), June 2001.
Wagner, H.P., Pepich, B.V., Frebis, C.,
Hautman, D.P. and Munch, D.J. 2002. U.S.
Environmental Protection Agency Method
326.0, a new method for monitoring
inorganic oxyhalides and optimization of
the postcolumn derivatization for the
selective determination of trace levels of
bromate. Journal of Chromatography. A.
Vol. 956 (93-101), May 2002.
Wallace, L.A. 1997. Human exposure and
Body Burden for Chloroform and Other
Trihalomethanes., Grit. Rev. Environ. Sci.
Technol. 27:113-94.
Waller, K., S.H. Swan, G. DeLorenze, B.
Hopkins. 1998. Trihalomethanes in
Drinking Water and Spontaneous Abortion.
Epidemiology. 9(2):134-140.
Waller, K., S.H. Swan, G.C. Windham, L.
Fenster. 2001. Influence of Exposure
Assessment Methods on Risk Estimates in
an Epidemiologic Study of Total
Trihalomethane Exposure and
Spontaneous Abortion. Journal of Exposure
Analysis and Environmental
Epidemiology. 11(6): 522-531.
Weisel, C.P. and W.K. Jo. 1996. Ingestion,
Inhalation, and Dermal Exposures to
Chloroform and Trichloroethene from Tap
Water. Environmental Health Perspectives.
104(1): 48-51.
WHO 2000. World Health Organization,
International Programme on Chemical
Safety (IPCS). Environmental Health
Criteria 216: Disinfectants and Disinfectant
By-products.
Williams, S.L., Rindfleisch, D.F., and
Williams, RL. 1995. Deadend on Haloacetic
Acids (HAA). In Proceedings of the 1994
AWWA Water Quality Technology
Conference, November 1994.
Windham GC, Waller K, Anderson M,
Fenster L, Mendola P, Swan S. 2003.
Chlorination by-Products in Drinking
Water and Menstrual Cycle Function.
Environ Health Perspect: doi:10.1289/
ehp.5922. http://ehpnetl.niehs.nih.gov/
docs/2003/5922/abstract.html
Yang, C.Y., H.F. Chiu, M.F. Cheng, et al.
1998. Chlorination of Drinking Water and
Cancer Mortality in Taiwan.
Environmental Research 78(l):l-6.
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49663
Yang, V., B. Cheng, S. Tsai, T. Wu, M. Lin
M. and K. Lin. 2000. Association between
Chlorination of Drinking Water and
Adverse Pregnancy Outcome in Taiwan.
Environ. Health. Perspect. 108:765-68.
Zheng, M., S. Andrews, and J. Bolton. 1999.
Impacts of medium-pressure UV on THM
and HAA formation in pre-UV chlorinated
drinking water. Proceedings, Water Quality
Technology Conference of the American
Water Works Association, Denver, CO.
List of Subjects
40 CFR Part 141
Chemicals, Indians-lands,
[ntergovernmental relations, Radiation
protection, Reporting and recordkeeping
requirements, Water supply.
40 CFR Part 142
Administrative practice and
procedure, Chemicals, Indians-lands,
Radiation protection, Reporting and
recordkeeping requirements, Water
supply.
40 CFR Part 143
Chemicals, Indians-lands, Water
supply.
Dated: July 11,2003.
Linda ]. Fisher,
Acting Administrator.
For the reasons set forth in the
preamble, title 40 chapter I of the Code
of Federal Regulations is proposed to be
amended as follows:
PART 141—NATIONAL PRIMARY
DRINKING WATER REGULATIONS
1. The authority citation for part 141
continues to read as follows:
Authority: 42 U.S.C. 300f, 300g-l, 300g-2,
300g-3, 300g-4, 300g-5,300g-6, 300J-4,
300J-9, and300j-ll.
2. Section 141.2 is amended by
adding, in alphabetical order,
definitions for "Combined distribution
system", "Consecutive system",
"Consecutive system entry point",
"Dual sample sets", "Finished water",
"Locational running annual average",
and "Wholesale system" to read as
follows:
§141.2 Definitions.
*****
Combined distribution system is the
interconnected distribution system
consisting of the distribution systems of
wholesale systems and of the
consecutive systems that receive
finished water from those wholesale
system(s).
*****
Consecutive system is a public water
system that buys or otherwise receives
some or all of its finished water from
one or more wholesale systems, for at
least 60 days per year.
Consecutive system entry point is a
location at which finished water is
delivered at least 60 days per year from
a wholesale system to a consecutive
system.
*****
Dual sample set is a set of two
samples collected at the same time and
same location, with one sample
analyzed for TTHM and the other
sample analyzed for HAAS. Dual sample
sets are collected for the purposes of
conducting an IDSE under subpart U of
this part and determining compliance
with the TTHM and HAA5 MCLs under
subpart V of this part.
Finished water is water that is
introduced into the distribution system
of a public water system and is intended
for distribution without further
treatment, except that necessary to
maintain water quality.
*****
Locational running annual overage
(LRAA) is the average of sample
analytical results for samples taken at a
particular monitoring site during the
previous four calendar quarters.
*****
Stage 2A is the period beginning [date
three years following publication of the
final rule] until the dates specified in
subpart V of this part for compliance
with Stage 2B, during which systems
must comply with Stage 2A MCLs in
§141.B4(b)(2).
*****
Wholesale system is a public water
system that treats source water and then
sells or otherwise delivers finished
water to another public water system for
at least 60 days per year. Delivery may
be through a direct connection or
through the distribution system of one
or more consecutive systems.
3. In § 141.23, the table in paragraph
(k)(l) is amended by revising entries 13,
18,19, and 20; revising the
undesignated text after the table; and
adding a new footnote 19 to read as
follows:
§141.23 Inorganic chemical sampling and
analytical requirements.
*****
(k) Inorganic analysis:
Contaminant and methodology13
EPA
ASTM3
SM4(18th, 19th
ed.)
SM"(20thed.)
Other
13. Fluoride:
Ion Chromatography 6300.0 D4327-97 4110 B 4110 B
19 300.1
Manual Distill.; Color. SPADNS 4500-F B, D 4500-F B, D
Manual Electrode D1179-93B 4500-F C 4500-F C
Automated Electrode
Automated Alizarin 4500-F E 4500-F E
380-75WE11
129-71W11
18. Nitrate:
Ion Chromatography
6300.0 D4327-97
19 300.1
6 353.2 D3867-90A
4110 B
Automated Cadmium Reduction 6353.2 D3867-90A 4500-NO3 F
Ion Selective Electrode 4500-NO3 D
Manual Cadmium Reduction D3867-90B 4500-NO3 E
19. Nitrite:
Ion Chromatography 6300.0 D4327-97 4110 B
19 300.1
Automated Cadmium Reduction 6353.2 D3867-90A 4500-NO3 F
Manual Cadmium Reduction D3867-90B 4500-NO3 E
Spectrophotometric , 4500-NO2 B
20. Orthophosphate:12
4110 B
4500-NO3 F
4500-NO3 D
4500-NOj E
4110 B
4500-NOj F
4500-NO3 E
4500-NO2 B
B10118
601 7
B-10118
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
Contaminant and methodology13
Colorimetric, automated, ascorbic acid
Colorimetric, ascorbic acid, single reagent
Colorimetric, phosphomolybdate
Automated-segmented flow
Automated discrete
Ion Chromatography
EPA ASTM *
6365 1
D515-88A
6 300 0 D4327 97
19 300.1
SM«(18th, 19th
ed.)
45QQ-P F
4500-P E
SM"(20thed.)
Other
tained from the Safe Drinking Water Hotline at 800-426-4791. Documents may be inspected at EPA's Drinking Water Docket EPA West 1301
Constitution Avenue NW., Room B102, Washington, DC 20460 (Telephone: 202-566-2426); or at the Office of the Federal Register 80o' North
Capitol Street, NW., Suite 700, Washington, DC.
*******
3 Annual Book of ASTM Standards, 1994, 1996, or 1999, Vols. 11.01 and 11.02, ASTM International; any year containing the cited version of
the method may be used. The previous versions of D1688-95A. D1688-95C (copper), D3559-95D (lead), D1293-95 (pH), D1125-91A (conduc-
tivity) and D859-94 (silica) are also approved. These previous versions D1688-90A, C; D3559-90D, D1293-84, D1125-91A and D859-88 re-
fPePtlveJy.are '?catld in the Annual Book of As™ Standards, 1994, Vol. 11.01. Copies may be obtained from ASTM International, 100 Barr
Harbor Dnve, West Conshohocken, PA 19428.
4 Standard Methods for the Examination of Water and Wastewater, 18th edition (1992), 19th edition (1995), or 20th edition (1998) American
Public Health Association, 1015 Fifteenth Street, NW, Washington, DC 20005. The cited methods published in any of these three editions mav
be used, except that the versions of 31 11 B.3111 D, 3113 B and 3114 B in the 20th edition may not be used
5 Method 1-2601-90, Methods for Analysis by the U.S. Geological Survey National Water Quality Laboratory— Determination of Inorganic and
Organic Constituents in Water and Fluvial Sediment, Open File Report 93-125, 1993; For Methods 1-1030-65' 1-1601-85" 1-1700-85- I-2598-
?^)r270(?r??; ?nd 'r3,300-85 See Techniques of Water Resources Investigation of 'the U.S. Geological Survey, Book 5, Chapter A-V 3rd ed
1989; Available from Information Services, U.S. Geological Survey, Federal Center, Box 25286, Denver, CO 80225-0425
DDftl^^Soo/^ the Determination of Inorganic Substances in Environmental Samples", EPA/600/R-93/100, August 1993. Available at NTIS
PB94— 120821. '
,.rt,. ln accordance with the Technical Bulletin 601 "Standard Method of Test for Nitrate in Drinking Water" July
1994, PN 221890-001, Analytical Technology, Inc. Copies may be obtained from ATI Orion, 529 Main Street, Boston MA 02129
^Method B-1 011, "Waters Test Method for Determination of Nitrite/Nitrate in Water Using Single Column Ion Chromatographv," August 1987
Copies may be obtained from Waters Corporation, Technical Services Division, 34 Maple Street, Mlford, MA 01757.
11 Industrial Method No 129-7 1W, "Fluoride in Water and Wastewater", December 1972, and Method No. 380-75WE, "Fluoride in Water and
Wastewater , February 1976, Technicon Industrial Systems. Copies may be obtained from Bran & Luebbe, 1025 Busch Parkway, Buffalo Grove,
12Unfiltered, no digestion or hydrolysis.
"Berause.MDLs reported in EPA Methods 200-7 and 200.9 were determined using a 2X preconcentration step during sample digestion
MDLs determined when samples are ana yzed by direct analysis (i.e., no sample digestion) will be higher. For direct analysis of cadmium and ar-
senic by Method 200.7, and arsenic by Method 3120 B sample preconcentration using pneumatic nebulization may be reguired to achieve lower
?f «l l?n^ To i Pre^?n^n^tl^umay^™b^^quir?d for direct ana|Vsis of antimony, lead, and thallium by Method 200.9; antimony and lead by
Method 3113 B; and lead by Method D3559-90D unless multiple in-furnace depositions are made.
J9"Methpds for Jhe Determination of Organic and Inorganic Compounds in Drinking Water", Vol. 1, EPA 815-R-00-014, August 2000. Avail-
able at NTIS, PB2000— 106981.
4. Section 141.24 is amended by
revising paragraph (e)(l) and by revising
entry 30 in the table in paragraph (e)(l)
to read as follows:
§ 141.24 Organic chemicals, sampling and
analytical requirements.
*****
(e) * * *
(1) The following documents are
incorporated by reference. This
incorporation by reference was
approved by the Director of the Federal
Register in accordance with 5 U.S.C.
552(a) and 1 CFR Part 51. Copies may
be inspected at EPA's Drinking Water
Docket, 1301 Constitution Avenue, NW.,
EPA West, Room B102, Washington, DC
20460 (Telephone; 202-566-2426); or at
the Office of the Federal Register, 800
North Capitol Street, NW., Suite 700,
Washington, DC. Method 508A and
515.1 are in Methods for the
Determination of Organic Compounds
in Drinking Water, EPA/600/4-88-039,
December 1988, Revised, July 1991.
Methods 547, 550 and 550.1 are in
Methods for the Determination of
Organic Compounds in Drinking
Water—Supplement I, EPA/600-4-90-
020, July 1990. Methods 548.1, 549.1,
552.1 and 555 are in Methods for the
Determination of Organic Compounds
in Drinking Water—Supplement II,
EPA/600/R-92-129, August 1992.
Methods 502.2, 504.1, 505, 506, 507,
508, 508.1, 515.2, 524.2 525.2, 531.1,
551.1 and 552.2 are in Methods for the
Determination of Organic Compounds
in Drinking Water— Supplement III,
EPA/600/R-95-131, August 1995.
Method 1613 is titled "Tetra-through
Octa-Chlorinated Dioxins and Furans by
Isotope-Dilution HRGC/HRMS", EPA/
821-B-94-005, October 1994. These
documents are available from the
National Technical Information Service,
NTIS PB91-231480, PB91-146027,
PB92-207703, PB95-261616 and PB95-
104774, U.S. Department of Commerce,
5285 Port Royal Road, Springfield,
Virginia 22161. The toll-free number is
800-553-6847. Method 6651 shall be
followed in accordance with Standard
Methods for the Examination of Water
and Wastewater, 18th edition [1992),
19th edition (1995), or 20th edition
(1998), American Public Health
Association (APHA); any of these three
editions may be used. Method 6610
shall be followed in accordance with
Standard Methods for the Examination
of Water and Wastewater, (18th Edition
Supplement) (1994), or with the 19th
edition (1995) or 20th edition (1998) of
Standard Methods for the Examination
of Water and Wastewater, any of these
publications may be used. The APHA
documents are available from APHA,
1015 Fifteenth Street NW., Washington,
D.C. 20005. Other required analytical
test procedures germane to the conduct
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49665
of these analyses are contained in
Technical Notes on Drinking Water
Methods, EPA/600/R-94-173, October
1994, NTIS PB95-104766. EPA Methods
515.3 and 549.2 are available from U.S.
Environmental Protection Agency,
National Exposure Research Laboratory
(NERL)—Cincinnati, 26 West Martin
Luther King Drive, Cincinnati, OH
45268. ASTM Method D 5317-93 is
available in the Annual Book of ASTM
Standards, (1999), Vol. 11.02, ASTM
International, 100 Barr Harbor Drive,
West Conshohocken, PA 19428, or in
any edition published after 1993. EPA
Method 515.4, "Determination of
Chlorinated Acids in Drinking Water by
Liquid-Liquid Microextraction,
Derivatization and Fast Gas
Chromatography with Electron Capture
Detection," Revision 1.0, April 2000,
EPA/815/B-00/001 and EPA Method
552.3, "Determination of Haloacetic
Acids and Dalapon in Drinking Water
by Liquid-Liquid Microextraction,
Derivatization, and Gas Chromatography
with Electron Capture Detection,"
Revision 1.0, July 2003 can be accessed
and downloaded directly on-line at
h tip://www. epa.gov/safewater/methods/
sourcalt.html. The Syngenta AG-625,
"Atrazine in Drinking Water by
Immunoassay", February 2001 is
available from Syngenta Crop
Protection, Inc., 410 Swing Road, Post
Office Box 18300, Greensboro, NC
27419, Phone number (336) 632-6000.
Method 531.2 "Measurement of N-
methylcarbamoyloximes and N-
methylcarbamates in Water by Direct
Aqueous Injection HPLC with
Postcolumn Derivatization," Revision
1.0, September 2001, EPA 815/B/01/002
can be accessed and downloaded
directly on-line at http://www.epa.gov/
safewater/m ethods/sourcah.html.
Contaminant
EPA method
Standard methods
ASTM
Other
30. Dalapon
552.1,515.1,
552.2, 515.3,
515.4, 552.3
1For previously approved EPA methods which remain available for compliance monitoring until June 1, 2001, see paragraph (e)(2) of this
section.
5. Section 141.33 is amended by
revising the first sentence of paragraph
a) introductory text, and adding
paragraph (f) to read as follows:
§141.33 Record maintenance.
* * * *
(a) Records of microbiological
analyses and turbidity analyses made
pursuant to this part shall be kept for
not less than 5 years. * * *
* * * *
(f) Copies of monitoring plans
developed pursuant to this part shall be
kept for the same period of time as the
records of analyses are required to be
kept under paragraph (a) of this section
or for three years after modification,
whichever is longer.
6. Section 141.53 is amended by
revising the table to read as follows:
5141.53 Maximum contaminant level goals
for disinfection byproducts.
Disinfection byproduct
Bromodichtoromethane
Bromoform
Bromate
Chlorite
Chloroform
Dibromochloromethane
Dichloroacetic acid
Monochloroacetic acid
Trichloroacetic acid
MCLG (mg/L)
zero.
zero.
zero.
0.8
0.07
0.06
zero.
0.03
0.02
7. Section 141.64 is revised to read.as
;ollows:
§141.64 Maximum contaminant levels for
disinfection byproducts.
(a) Bromate and chlorite. The
maximum contaminant levels (MCLs)
forbromate and chlorite are as follows:
Disinfection byproduct
MCL (mg/L)
0.010
1.0
(1) Compliance dates for CWSs and
NTNCWSs. Subpart H systems serving
10,000 or more persons must comply
with this paragraph (a) beginning
January 1, 2002. Subpart H systems
serving fewer than 10,000 persons and
systems using only ground water not
under the direct influence of surface
water must comply with this paragraph
(a) beginning January 1, 2004.
(2) Best available technology. The
Administrator, pursuant to section 1412
of the Act, hereby identifies the
following as the best technology,
treatment techniques, or other means
available for achieving compliance with
the maximum contaminant levels for
bromate and chlorite identified in this
paragraph (a):
Disinfection
byproduct
Bromate
Best available technology
Control of ozone treatment
process to reduce produc-
tion bromate.
Disinfection
byproduct
Best available technology
Chlorite
Control of treatment processes
to reduce disinfectant de-
mand and control of dis-
infection treatment proc-
esses to reduce disinfectant
levels.
(b) TTHM and HAAS.
(1) Subpart L—RAA compliance, (i)
Compliance dates. Subpart H systems
serving 10,000 or more persons must
comply with this paragraph (b)(l)
beginning January 1, 2002 until the date
specified for subpart V of this part
compliance in § 141.620{c). Subpart H
systems serving fewer than 10,000
persons and systems using only ground
water not under the direct influence of
surface water must comply with this
paragraph (b)(l) beginning January 1,
2004 until the date specified for subpart
V of this part compliance in
§141.620(c).
Disinfection byproduct
Total trihalomethanes (TTHM)
Haloacetic acids (five) (HAAS)
MCL
(mg/L)
0.080
0.060
(ii) Best available technology. The
Administrator, pursuant to section 1412
of the Act, hereby identifies the
following as the best technology,
treatment techniques, or other means
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Federal Register/Vol. 68, No. 159/Monday. August 18, 2003/Proposed Rules
available for achieving compliance with
the maximum contaminant levels for
TTHM and HAAS identified in this
paragraph (b)(l):
Disinfection byproduct
Total trihalomethanes
(TTHM) and
Halaocetic acids
(five) (HAAS).
Best available
technology
Enhanced coagula-
tion or enhanced
softening or
GAG 10, with chlo-
rine as the primary
and residua)
disinfectant.
(2) Stage 2A—LRAA compliance, (i)
Compliance dates. The Stage 2A MCLs
for TTHM and HAAS must be complied
with as a locational running annual
average at each subpart L of this part
compliance monitoring location under
§ 141.136 beginning [date three years
after publication of the final rule] until
the date specified for subpart V of this
part compliance in § 141,620(c).
Disinfection byproduct
Total trihalomethanes (TTHM)
Haloacetic acids (five) (HAAS)
MCL
(mg/L)
0.120
0.100
(ii) Best available technology. The
Administrator, pursuant to section 1412
of the Act, hereby identifies the
following as the best technology,
treatment techniques, or other means
available for achieving compliance with
the maximum contaminant levels for
TTHM and HAA5 identified in this
paragraph (b)(2):
Disinfection
byproduct
Best available
technology
Total
trihalomethanes
{TTHM) and
Haloacetic acids
(five) (HAAS).
Enhanced coagulation
or enhanced soft-
ening orGACIO, with
chlorine as the pri-
mary and residual
disinfectant.
(3) Subpart V LRAA compliance, (i)
Compliance dates. The subpart V of this
part MCLs for TTHM and HAAS must
be complied with as a locational
running annual average at each
monitoring location beginning the date
specified for Subpaxt V of this part
compliance in § 141.620(c).
Disinfection byproduct
Total trihalomethanes (TTHM)
Haloacetic acids (five) (HAAS)
MCL
(mg/L)
0.080
0.060
(ii) Best technology for systems that
disinfect their source water. The
Administrator, pursuant to section 1412
of the Act, hereby identifies the
following as the best technology,
treatment techniques, or other means
available for achieving compliance with
the maximum contaminant levels for
TTHM and HAAS identified in this
paragraph (b)(3) for all systems that
disinfect their source water:
Disinfection
byproduct
Total
trihalomethan-
es (TTHM)
and
Haloacetic
adds (five)
(HAAS).
Best available technology
Enhanced coagulation or
enhanced softening, plus
GAC10;ornanoftltration
with a molecular weight
and cutoff 51000 Dai-
tons; or GAC20.
(iii) Best available technology for
systems that buy disinfected water. The
Administrator, pursuant to section 1412
of the Act, hereby identifies the
following as the best technology,
treatment techniques, or other means
available for achieving compliance with
the maximum contaminant levels for
TTHM and HAA5 identified in this
paragraph (b)(3) for systems that buy
disinfected water:
Disinfection
byproduct
Total
trihalomethan-
es (TTHM)
and
Haloacetic
acids (five)
(HAAS).
Best available technology
Improved distribution sys-
tem and storage tank
management to reduce
detention time plus the
use of chloramines for
disinfectant residual
maintenance.
(c) Extensions. A system that is
installing GAG or membrane technology
to comply with the MCLs in paragraphs
(a) or (b)(l) of this section may apply to
the State for an extension of up to 24
months past January 1, 2002, but not
beyond January 1, 2004. In granting the
extension, States must set a schedule for
compliance and may specify any
interim measures that the system must
take. Failure to meet the schedule or any
interim treatment requirements
constitutes a violation of a National
Primary Drinking Water Regulation.
Subpart L—[Amended]
8. Section 141.131 is amended by
revising paragraphs (a), (b), (d)(2), (d)(3),
(d)(4)(i), (d)(4)(ii), and the table in
paragraph (c)(l), and adding paragraph
(d)(6) to read as follows:
§141.131 Analytical requirements.
(a) General. (1) Systems must use only
the analytical methods specified in this
section, or their equivalent as approved
by EPA, to demonstrate compliance
with the requirements of this subpart
and with the requirements of subparts U
and V. These methods are effective for
compliance monitoring February 16,
1999, unless a different effective date is
specified in this section or by the State.
(2) The following documents are
incorporated by reference. The Director
of the Federal Register approves this
incorporation by reference in
accordance with 5 U.S.C. 552(a) and 1
CFR part 51. Copies may be inspected
at EPA's Drinking Water Docket, 1301
Constitution Avenue, NW., EPA West,
Room B102, Washington, DC 20460, or
at the Office of the Federal Register, 800
North Capitol Street, NW., Suite 700,
Washington, DC. EPA Method 552.1 is
in Methods for the Determination of
Organic Compounds in Drinking Water-
Supplement U, USEPA, August 1992,
EPA/600/R-92/129 (available through
National Information Technical Service
(NTIS), PB92-207703). EPA Methods
502.2, 524.2, 551.1, and 552.2 are in
Methods for the Determination of
Organic Compounds in Drinking Water-
Supplement III, USEPA, August 1995,
EPA/600/R-95/131. (Available through
NTIS, PB95-261616). EPA Method
300.0 for chlorite and bromide is in
Methods for the Determination of
Inorganic Substances in Environmental
Samples, USEPA, August 1993, EPA/
600/R-93/100 (available through NTIS,
PB94-121811). EPA Methods 300.1 for
chlorite, bromate, and bromide and
321.8 for bromate are in Methods for the
Determination of Organic and Inorganic
Compounds in Drinking Water, Volume
1, USEPA, August 2000, EPA 815-R-
00-O14 (available through NTIS,
PB2000-106981}. EPA Method 317.0,
Revision 2.0, "Determination of
Inorganic Oxyhalide Disinfection By-
Products in Drinking Water Using Ion
Chromotography with the Addition of a
Postcolumn Reagent for Trace Bromate
Analysis," USEPA, July 2001, EPA 815-
B-01-001, EPA Method 326.0, Revision
1.0, "Determination of Inorganic
Oxyhalide Disinfection By-Products in
Drinking Water Using Ion
Chromatography Incorporating the
Addition of a Suppressor Acidified
Postcolumn Reagent for Trace Bromate
Analysis," USEPA, June 2002, EPA 815-
R-03-007, EPA Method 327.0, Revision
1.0, "Determination of Chlorine Dioxide
and Chlorite Ion in Drinking Water
Using Lissamine Green B and
Horseradish Peroxidase with Detection
by Visible Spectrophotometry," USEPA,
July 2003, and EPA Method 552.3,
Revision 1.0, "Determination of
Haloacetic Acids and Dalapon in
Drinking Water by Liquid-liquid
Extraction, Derivatization, and Gas
Chromatography with Electron Capture
Detection," USEPA, July 2003, can be
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49667
accessed and downloaded directly on-
line at www.epa.gov/sajewater/
methods/sourcalt.html. EPA Method
i!5.3, Revision 1.0, "Determination of
rotal Organic Carbon and Specific UV
Absorbance at 254 nm in Source Water
and Drinking Water," USEPA, June
2003, is available from: Chemical
Exposure Research Branch,
Microbiological & Chemical Exposure
Assessment Research Division, National
Exposure Research Laboratory, U.S.
Environmental Protection Agency,
incinnati, OH 45268, Fax Number
513-569-7757, Phone number: 513-
569-7586. Standard Methods 4500-C1
D, 4500-C1 E, 4500-C1 F, 4500-C1 G,
4500-C1 H, 4500-C11, 4500-C1O2 E,
5251 B, and 5910 B shall be followed in
accordance with Standard Methods for
the Examination of Water and
Wastewater, 19th or 20th Editions or the
On-Line Version, American Public
Health Association, 1995,1998, and
2003, respectively. The cited methods
published in any of these three editions
may be used. Standard Method 4500-
ClOa D shall be followed in accordance
with Standard Methods for the
Examination of Water and Wastewater,
19th or 20th Editions, American Public
Health Association, 1995 and 1998,
respectively. Standard Methods 5310 B,
5310 C, and 5310 D shall be followed in
accordance with the Supplement to the
19th Edition of Standard Methods for
the Examination of Water and
Wastewater, or the Standard Methods
for the Examination of Water and
Wastewater, 20th Edition, or the On-
Line Version, American Public Health
Association, 1995,1998, and 2003,
respectively. The cited methods
published in any of these editions may
be used. Copies may be obtained from
the American Public Health
Association, 1015 Fifteenth Street, NW.,
Washington, DC 20005. ASTM Method
D 1253-86 shall be followed in
accordance with the Annual Book of
ASTM Standards, Volume 11.01,
American Society for Testing and
Materials, 1996 or any year containing
the cited version of the method may be
used. ASTM D 6581-00 shall be
followed in accordance with the Annual
Book of ASTM Standards, Volume
11.01, American Society for Testing and
Materials, 2001 or any year containing
the cited version of the method may be
used; copies may be obtained from the
American Society for Testing and
Materials, 100 Barr Harbor Drive, West
Conshohoken, PA 19428-2959.
(b) Disinfection byproducts. (1)
Systems must measure disinfection
byproducts by the methods (as modified
by the footnotes) listed in the following
table:
APPROVED METHODS FOR DISINFECTION BYPRODUCT COMPLIANCE MONITORING
Contaminant and methodology
EPA method
Standard
Method2
ASTM
Method3
TTHM:
P&T/GC/EtCD & PID
P&T/GC/MS
LLE/GC/ECD
HAAS:
LLE (dtazomethane)/GC/ECD ...
SPE (acidic methanol)/GC/ECD
LLE (acidic methanol)/GC/ECD ,
Bromate:
Ion chromatography
Ion chromatography & post column reaction
1C/ICP-MS
Chlorite:
Amperometric titration
Spectrophotometry ..
ton chromatography
502.2 4
524.2
551.1
552.1 5
552:2, 552.3.
300.1
317.0 Rev 2.06, 326.06
321.8 6-7
327.0 8.
300.0, 300.1, 317.0 Rev. 2.0, 326.0
6251 B5.
4500-C1O2
E8.
D 6581-
00
D 6581-
00
1 P&T = purge and trap; GC = gas chromatography; EICD = electrolytic conductivity detector; PID = photoiontzation detector; MS = mass spec-
trometer; LLE = liquid/liquid extraction; ECD = electron capture detector; SPE = solid phase extraction; 1C = ion chromatography; ICP-MS = in-
ductively coupled plasma/mass spectrometer
2 219th or 20th editions or the On-Line Version of Standard Methods for the Examination of Water and Wastewater, 1995, 1998, and 2003, re-
spectively, American Public Health Association; any of these editions may be used.
3 Annual Book of ASTM Standards, 2001 or any year containing the cited version of the method, Vol 11.01.
4 If TTHMs are the only analytes being measured in the sample, then a PID is not required.
5The samples must be extracted within 14 days of sample collection.
6 Ion chromatography & post column reaction or IC/ICP-MS must be used for monitoring of bromate for purposes of demonstrating eligibility of
•educed monitoring, as prescribed in §141.132(b)(3){ii).
7 Samples must be preserved at the time of sampling with 50 mg ethylenediamine (EDA)/L of sample and must be analyzed within 28 days.
8 Amperometric titration or Spectrophotometry may be used for routine daily monitoring of chlorite at the entrance to the distribution system, as
arescribed in §141.132(b)(2)(i)(A). Ion chromatography must be used for routine monthly monitoring of chlorite and additional monitoring of chlo-
•ite in the distribution system, as prescribed in §141.132(b)(2)(i)(B) and (b)(2)(ii).
(2) Analysis under this section for
disinfection byproducts must be
conducted by laboratories that have
received certification by EPA or the
State, except as specified under
paragraph (b)(3)of this section. To
receive certification to conduct analyses
For the DBF contaminants in §§ 141.64,
141.135, and subparts U and V of this
part, the laboratory must:
(i) Analyze Performance Evaluation
(PE) samples that are acceptable to EPA
or the State at least once during each
consecutive 12 month period by each
method for which the laboratory desires
certification.
(ii) Achieve quantitative results on the
PE sample analyses that are within the
following acceptance limits which
become effective [date 60 days after date
of final rule publication] for purposes of
certification:
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
DBF
TTHM:
Bromodichloromethane
Dlbromochloromethane
HAAS:
Monochloroacetic Acid ...
Dichloroacetic Acid
Trichloroacetic Acid
Monobromacetic Acid
Dibromoacetic Acid
Chlorite
Acceptance
limits
(percent)
±20
±20
±20
±20
±40
±40
±40
±40
±40
±30
±30
Comments
Laboratory must meet all 4 individual THM acceptance limits in
order to successfully pass a PE sample for TTHM.
Laboratory must meet the acceptance limits for 4 out of 5 of
the HAAS compounds in order to successfully pass a PE
sample for HAAS.
(iii) Report quantitative data for
concentrations at least as low as the
ones listed in tha following table for all
DBF samples analyzed for compliance
with §§ 141.64, 141.135, 141.136, and
subparts U and V of this part:
DBP
Minimum re-
porting level
(ufl/L)7
Comments
TTHM2:
Chloroform
Bromodichloromethane
Dibromochioromethane
Bromoform
HAA5:2
Monochloroacetic Acid
Dichloroacetic Acid
Trichloroacetic Acid
Monobromoacetic Acid
Dibromoacetic Acid
Chlorite
Bromate
1.0
1.0
1.0
1.0
2.0
1.0
1.0
1.0
1.0
200.
5.0 or 1.0
Laboratories that use EPA Methods 317.0 Revision 2.0, 326.0
or 321.8 must meet a 1.0 ng/L MRL for bromate.
1The calibration curve must encompass the minimum reporting level (MRL) concentration and the laboratory must verify the accuracy of the
calibration curve at the lowest concentration for which quantitative data are reported by analyzing a calibration check standard at that concentra-
tion at the beginning of each batch of samples. The measured concentration for the check standard must be within ±50% of the expected value.
Data may be reported for concentrations lower than the MRL as long as the precision and accuracy criteria are met by analyzing a standard at
the lowest reporting limit chosen by the laboratory.
2When adding the individual trihalomethane or haloacetic acid concentrations to calculate the TTHM or HAAS concentrations, respectively, a
zero is used for any analytical result that is less than the MRL concentration for that DBP.
(3) A party approved by EPA or the
State must measure daily chlorite
samples at the entrance to the
distribution system.
(c)
(1)
Methodology
Low Level Amperometric Titration
DPD Ferrous Titrimetric
DPD Colorimetric
Syringaldazine (FACTS)
lodometric Electrode
DPD
Amperometric Method II
Lissamine Green Spectrophotometric ...
Standard
method
4500-CI D
4500-CI E
4500-CI F
4500-CI G
4500-CI
4500-CI
4500-CIO;
4500-CIC-2
- E
ASTM
method
D 1253-86
EPA method
327.0
Residual Measured 1
Free
chlorine
X
X
X
X
Combined
chlorine
X
X
X
Total
chlorine
X
X
X
X
X
Chlorine
dioxide
X
X
X
1X indicates method is approved for measuring specified disinfectant residual. Free chlorine or total chlorine may be measured for dem-
onstrating compliance with the chlorine MRDL and combined chlorine or total chlorine may be measured for demonstrating compliance with the
chloramine MRDL.
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
49669
(d) * * *
(2) Bromide. EPA Methods 300.0,
300.1, 317.0 Revision 2.0, 326.0, or
ASTM D 6581-00.
(3) Total Organic Carbon (TOO).
Standard Method 5310 B (High-
Temperature Combustion Method) or
Standard Method 5310 C (Persulfate-
Ultraviolet or Heated-Persulfate
Oxidation Method) or Standard Method
5310 D (Wet-Oxidation Method) or EPA
Method 415.3. Inorganic carbon must be
removed from the samples prior to
analysis. TOG samples may not be
filtered prior to analysis. TOG samples
must be acidified at the time of sample
collection to achieve pH less than or
equal to 2 with minimal addition of the
acid specified in the method or by the
instrument manufacturer. Acidified
TOG samples must be analyzed within
28 days.
m * * *
(i) Dissolved Organic Carbon (DOC).
Standard Method 5310 B (High-
Pemperature Combustion Method) or
Standard Method 5310 C (Persulfate-
LJltraviolet or Heated-Persulfate
Dxidation Method} or Standard Method
5310 D (Wet-Oxidation Method) or EPA
vlethod 415.3. DOC samples must be
•iUered through the 0.45 urn pore-
iiameter filter as soon as practical after
sampling, not to exceed 48 hours. After
iltration, DOC samples must be
icidified to achieve pH less than or
qual to 2 with minimal addition of the
icid specified in the method or by the
nstrument manufacturer. Acidified
DOC samples must be analyzed within
i8 days. Inorganic carbon must be
-emoved from the samples prior to
malysis. Water passed through the filter
jriorto filtration of the sample must
ierve as the filtered blank. This filtered
>iank must be analyzed using
>rocedures identical to those used for
malysis of the samples and must meet
he following criteria: DOC < 0.5 mg/L.
(ii) Ultraviolet Absorption at 254 nm
UV254). Standard Method 5910 B
Ultraviolet Absorption Method) or EPA
Method 415.3. UV absorption must be
neasured at 253.7 nm (may be rounded
tff to 254 nm). Prior to analysis, UV254
amples must be filtered through a 0.45
im pore-diameter filter. The pH of
JV254 samples may not be adjusted.
iampies must be analyzed as soon as
»ractical after sampling, not to exceed
8 hours.
* * * *
(6) Magnesium. All methods allowed
n §141.23(k)(l) for measuring
aagnesium.
9. Section 141.132 is amended by
evising paragraphs (b)(3)(ii) and (e) to
sad as follows:
§141.132 Monitoring requirements.
*****
(b)* * *
(i) * * *
(ii) Reduced monitoring.
(A) Until [date three years from final
rule publication], systems required to
analyze for bromate may reduce
monitoring from monthly to quarterly, if
the system's average source water
bromide concentration is less than 0.05
mg/L based on representative monthly
bromide measurements for one year.
The system may remain on reduced
bromate monitoring until the running
annual average source water bromide
concentration, computed quarterly, is
equal to or greater than 0.05 mg/L based
on representative monthly
measurements. If the running annual
average source water bromide
concentration is >0.05 mg/L, the system
must resume routine monitoring
required by paragraph (b)(3)(i) of this
section.
(B) Beginning [date three years from
final rule publication], systems may no
longer use the provisions of paragraph
(b)(3)(ii)(A) of this section to qualify for
reduced monitoring. A system required
to analyze for bromate may reduce
monitoring from monthly to quarterly, if
the system's running annual average
bromate concentration is less than
0.0025 mg/L based on monthly bromate
measurements under paragraph (b)(3)(i)
of this section for the most recent four
quarters, with samples analyzed using
Method 317.0 Revision 2.0, 325.0 or
321.8. If a system has qualified for
reduced bromate monitoring under
paragraph (b)(3)(ii)(A) of this section,
that system may remain on reduced
monitoring as long as the running
annual average of quarterly bromate
samples does not exceed 0.0025 mg/L
based on samples analyzed using
Method 317.0 Revision 2.0, 325.0, or
321.8. If the running annual average
bromate concentration is >0.0025 mg/L,
the system must resume routine
monitoring required by paragraph
(b)(3}(i) of this section.
*****
(e) Monitoring requirements for source
water TOC. In order to qualify for
reduced monitoring for TTHM and
HAAS under paragraph (b)(l)(ii) of this
section, subpart H systems not
monitoring under the provisions of
paragraph (d) of this section must take
monthly TOC samples approximately
every 30 days at a location prior to any
treatment. In addition to meeting other
criteria for reduced monitoring in
paragraph Eb}(l)(ii) of this section, the
source water TOC running annual
average must be <4.0 mg/L (based on the
most recent four quarters of monitoring)
on a continuing basis at each treatment
plant to reduce or remain on reduced
monitoring for TTHM and HAAS.
*****
10. Section 14l!l34 is amended by
revising paragraph (b) introductory text
to read as follows:
§141.134 Reporting and recordkeeping
requirements.
*****
(b) Disinfection byproducts. In
addition to reporting required under
§141.136(e), systems must report the
information specified in the following
table:
*****
11. Section 141.135 is amended by
revising paragraph (a)(3)(ii) to read as
follows:
§ 141.135 Treatment technique for control
of disinfection byproduct (DBF) precursors.
(a) * * *
(3)* * *
(ii) Softening that results in removing
at least 10 mg/L of magnesium hardness
(as CaCOj), measured monthly
according to § 141.131(d)(6) and
calculated quarterly as a running annual
average.
*****
12. Section 141.136 is added to
subpart L to read as follows:
§141.136 Additional compliance
requirements for Stage 2A.
(a) Applicability. Any system that
takes TTHM and HAAS compliance
samples under this subpart at more than
one location in its distribution system is
subject to additional MCL requirements
beginning [date 3 years after publication
of final rule] until the dates identified
for compliance with subpart V in
§ 141.620(c). Any system that takes
samples at more than one location must
calculate a locational running annual
average (LRAA) for each sampling point
and comply with the MCLs of 0.120 mg/
L for TTHM and 0.100 mg/L for HAAS
listed in § 141.64(b)(2), except as
provided for under paragraph (c) of this
section.
(b) Compliance. (1) Systems must
calculate a locational running annual
average each quarter for each
monitoring location at which they took
TTHM and HAA5 samples under their
monitoring plan developed under
§ 141.132(f) by averaging the results of
TTHM or HAAS monitoring at that
sample location during the four most
recent quarters.
(2) Systems required to conduct
quarterly monitoring under this subpart
must begin to make compliance
calculations under paragraph (b) of this
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
section at the end of the fourth calendar
quarter that follows the compliance date
in paragraph (a) of this section and at
the end of each subsequent quarter.
Systems required to conduct monitoring
at a frequency that is less than quarterly
under this subpart must make
compliance calculations under
paragraph (b) of this section beginning
with the first compliance sample taken
after the compliance date in paragraph
(a) of this section.
(3) Failure to monitor will be treated
as a monitoring violation for each
quarter that a monitoring result would
be used in a locational running annual
average compliance calculation.
{c) Consecutive systems. A
consecutive system must comply with
the TTHM and HAAS MCLs in
§ I41.64(b)(2) at each monitoring
location in its distribution system
identified in its monitoring plan
developed under §141.132(f),
(d) Reporting. Systems must submit
the compliance calculations and
locational running annual averages
under this section as part of the reports
required under § 141.134.
Subpart O—[Amended]
13. Section 141.151 is amended by
revising paragraph (d) to read as
follows:
§141.151
subpart.
Purpose and applicability of this
(d) For the purpose of this subpart,
detected means: At or above the levels
prescribed by § 141.23(a)(4) for
inorganic contaminants, at or above the
levels prescribed by § 141.24(f)(7) for
the contaminants listed in § 141.61(a), at
or above the levels prescribed by
§ 141.24(h)(18) for the contaminants
listed in § 141.61(c), at or above the
levels prescribed by § 141.131(bJ(2)(iii)
for the contaminants or contaminant
groups listed in §141.64 and
§ 141.153(d)(iv), and at or above the
levels prescribed by § 141.25(c) for
radioactive contaminants.
*****
14. Section 141.153 is amended by
revising paragraphs (d)(4)(iv)(B) and
(d)(4)(iv)(C) to read as follows:
§ 141.153 Content of the reports.
*****
(d)* * *
(4) * * *
(iv) * * *
(B) When compliance with the MCL is
determined by calculating a running
annual average of all samples taken at
a sampling point: the highest average of
any of the sampling points and the
range of all sampling points expressed
in the same units as the MCL. For the
MCLs for TTHM and HAA5 in
§ 141.64(b)(2) and (3), systems must
include the highest locational running
annual average for TTHM and HAAS
and the range of individual sample
results for all sampling points expressed
in the same units as the MCL. If more
than one site exceeds the MCL, the
system must include the locational
running annual averages for all sites that
exceed the MCL.
(C) When compliance with the MCL is
determined on a system-wide basis by
calculating a running annual average of
all samples at all sampling points: the
average and range of detection
expressed in the same units as the MCL.
The system is not required to include
the range of individual sample results
for the IDSE conducted under subpart U
of this part.
Subpart Q—[Amended]
15. In Appendix A, the table is
amended by revising entries I.G.I and
1.G.2, and endnotes 12 and 20, to read
as follows:
APPENDIX A TO SUBPART Q OF PART 141—NPDWR VIOLATIONS AND OTHER SITUATIONS REQUIRING PUBLIC NOTICE 1
Contaminant
MCL/MRDL/TT violations2
Tier of pub-
lic notice Citation
required
Monitoring and testing procedure violations
Tier of pub-
lic notice Citation
required
I. Violations of National Primary Drinking Water Regula-
tions (NPDWR):3
G. Disinfection Byproducts, * *
1.
2.
Total trihalomethanes (TTHM)
Haloacetic acids (HAAS)
2
2
141.1212,
141.64(b)M
141.64(b)20
3
3
141.3012,
141.132(aHb)20,
141.620-.630
141.132(aMb)2°,
141.620-.630
Appendix A—Endnotes
12. §§141.12 and 141.30 will no longer
apply after December 31, 2003.
*****
20. §§141.64fb)(l) and 141.132(a)-(b) apply
until §§ 141.64(b)(3) and 141.62u-.630 take
effect under the schedule in § 141.620(c).
§ 141.64(b)(2) takes effect on [date three years
following final rule publication] and remains
in effect until the effective dates for subpart
V of this part compliance in the table in
§141.620(c).
16. In Appendix B the table is
amended by revising entries H.79, H.80,
and endnote 17, and adding endnote 23,
to read as follows:
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49671
APPENDIX B TO SUBPART Q OF PART 141—STANDARD HEALTH EFFECTS LANGUAGE FOR PUBLIC NOTIFICATION
Standard health
MCLG1 mgl Mr| 2 « effects language
L MUL mg/L for public
notification
Contaminant
H. Disinfection Byproducts (DBPs), • • *".
. Total trihafomethanes (TTHLM) N/A
JO. Haloacetic acids (HAAS) N/A
0.10/0.120/0.080 '"•
0.060/0.1002P.«
Vppendix B—Endnotes
* * * *
17. Surface water systems and ground
vater systems under the direct influence of
iurface water are regulated under subpart H
>f 40 CFR 141. Subpart H community and
ion-transient non-community systems
ierving £10,000 must comply with subpart L
3BP MCLs and disinfectant maximum
esidual disinfectant levels (MRDLs)
>eginning January 1, 2002. All other
:ommunity and non-transient non-
jommunity systems must comply with
mbpart L DBF MCLs and disinfectant MRDLs
reginning January 1, 2004. Subpart H
ransient non-community systems serving
:10,000 that use chlorine dioxide as a
lisinfectant or oxidant must comply with the
ihlorine dioxide MRDL beginning January 1,
!002. All other transient non-community
ystems that use chlorine dioxide as a
lisinfectant or oxidant must comply with the
ihlorine dioxide MRDL beginning January 1,
!004.
* * * *
23. Community and non-transient nori-
:ommunity systems must comply with
[THM and HAAS MCLs of 0.120 mg/L and
1.100 mg/L, respectively (with compliance
;alculated as a locational running annual
iverage) beginning [date three years
ollowing publication of final rule] until they
ire required to comply with subpart V TTHM
md HAAS MCLs of 0.080 mg/L and 0.060
ng/L, respectively (with compliance
:alculated as a locational running annual
verage). Community and non-transient non-
;ommunity systems serving SI 0,000 must
iomply with subpart V TTHM and HAA5
ACLs {with compliance calculated as a
ocational running annual average) beginning
date six years following publication of final
u!e]. Community and non-transient non-
immunity systems serving <1Q,000 must
comply with subpart V TTHM and HAAS
MCLs (with compliance calculated as a
locational running annual average) beginning
[date 90 months following publication of
final rule].
*****
17. Part 141 is amended by adding
new subpart U to read as follows:
Subpart U—Initial Distribution System
Evaluations
Sec.
141.600 General requirements.
141.601 Initial Distribution System
Evaluation (IDSE) requirements.
141.602 IDSE monitoring.
141.603 Alternatives other than IDSE
monitoring.
141.604 IDSE reports.
141.605 Subpart V monitoring location
recommendations to the State.
Subpart U—Initial Distribution System
Evaluations
§141.600 General requirements.
(a) The requirements of subpart U
constitute national primary drinking
water regulations. The regulations in
this subpart establish monitoring and
other requirements for identifying
compliance monitoring locations to be
used for determining compliance with
maximum contaminant levels for total
trihalomethanes (TTHM) and haloacetic
acids (five)(HAA5) in subpart V through
the use of an Initial Distribution System
Evaluation (IDSE). IDSEs are studies,
used in conjunction with subpart L
compliance monitoring, to identify and
select subpart V compliance monitoring
sites that represent high TTHM and
HAA5 levels throughout the distribution
system. The studies will be based on
system-specific monitoring as provided
in § 141.602. As an alternative, you may
use other system-specific data that
provide equivalent or better information
on site selection for monitoring under
subpart V as provided for in
§141.603(a).
(b) Applicability. You are subject to
these requirements if your system is a
community water system that adds a
primary or residual disinfectant other
than ultraviolet light or delivers water
that has been treated with a primary or
residual disinfectant other than
ultraviolet light or if your system is a
nontransient noncommunity water
system that serves at least 10,000 people
and adds a primary or residual
disinfectant other than ultraviolet light
or delivers water that has been treated
with a primary or residual disinfectant
other than ultraviolet light. You must
conduct an Initial Distribution System
Evaluation (IDSE), unless you meet the
40/30 certification criteria in
§ 141.603(b) or the State has granted a
very small system waiver for the IDSE
or you meet the criteria defined by the
State for a very small system waiver
under § 141.603(c). If you have a very
small system waiver for the IDSE under
§ 141.603(c), you are not required to
submit an IDSE report. All other
systems must submit an IDSE report,
even if you meet the 40/30 certification
criteria in §141.603(c).
(c) Schedule. You must comply with
the Initial Distribution System
Evaluation (IDSE) on the schedule in the
following table, based on your system
type.
If you are this type of system
You must submit your IDSE report to the state by1
1) Subpart H serving >10,000 [date 24 mos. following publication of final rule]
2) Subpart H serving <10,000 [date 24 mos. following publication of final rule]2
3) Ground water serving £10,000 [date 24 mos. following publication of final rule]
4) Ground water serving <10,000 [date 24 mos. following publication of final rule]2
5) Consecutive system at the same time as the system with the earliest compliance date in the com-
bined distribution system 3
1 Systems that meet the 40/30 certification criteria in § 141.603(b) are encouraged to submit their IDSE report as soon as the certification cri-
sria are met.
2 You must comply by [date 24 mos. following publication of final rule] if you are a wholesale system and any system in the combined distribu-
ion system serves at least 10,000 people. You must comply by [date 48 mos. following publication of final rule] if no system in the combined dis-
ibution system serves at least 10,000 people.
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
3 You must comply by [date 24 mos. following publication of final rule] if any system in the combined distribution system serves at least 10 000
people. You must comply by [date 48 mos. following publication of final rule] if no system in the combined distribution system serves at leasl
10,000 people.
(d) Violations. You must comply with
specific monitoring and reporting
requirements. You must prepare for,
conduct, analyze, and submit your IDSE
report no later than the date specified in
§ 141.600(c). Failure to conduct a
required IDSE or to submit a required
IDSE report by the date specified in
paragraph (c) of this section is a
monitoring violation. If you do not
submit your IDSE report to your State,
or if you submit the report after the
specified date, you must comply with
any additional State-specified
requirements, which may include
conducting another IDSE.
§ 141.601 Initial Distribution System
Evaluation (IDSE) requirements.
(a) You must conduct an IDSE that
meets the requirements in § 141,602 or
§ 141.603(a) or meet the 40/30
certification criteria in § 141.603(b) or
have received a very small system
waiver for the IDSE from the State under
§ 141.603(c). If you do not take the full
complement of TTHM and HAAS
IDSE ALTERNATIVES
compliance samples required of a
system with your population and source
water under subpart L, but are required
to conduct an IDSE under this subpart,
you are not eligible for either the 40/30
certification in §141.603(b) or the very
small system waiver in § 141.603(c) and
must conduct an IDSE that meets the
requirements in § 141.602 or
§141.603(a).
(b) You may use any alternative listed
in the table below for which you
qualify.
Alternatives
(1) Monitoring
(2) System-specific study ....
(3) 40/30 certification
(4) Very small system waiv-
er.
Eligibility
All systems required to conduct an IDSE
All systems required to conduct an IDSE
ance samples <0.030 mg/L during the period specified in §141.603(b).
Any system serving <500 for which the State has granted a waiver
Regulatory reference
S 141 602
§ 141 603(a)
§141 603(c)
(c) IDSE results will not be used for
the purpose of determining compliance
withMCLsin§141.64.
(d) Additional provisions:
(1) You may consider multiple wells
drawing water from a single aquifer as
one treatment plant for determining the
minimum number of TTHM and HAAS
samples required, with State approval in
accordance with criteria developed
under §142.16(h)(5) of this chapter.
State approvals made under
§ 141.132(a)(2) to treat multiple wells
drawing water from a single aquifer as
one treatment plant remain in effect
unless withdrawn by the State.
(2) If you are a consecutive system,
you must comply with the IDSE
requirements in this subpart based on
whether you buy some or all of your
water from another PWS during 2004 for
systems with an IDSE report due [date
24 months after publication of final
rule] or during 2006 for systems with an
IDSE report due [date 48 months after
publication of final rule]. A consecutive
system that buys some, but not all, of its
finished water during the period
identified in this paragraph must treat
each consecutive system entry point
from a wholesale system as a treatment
plant for the consecutive system for the
purpose of determining monitoring
requirements of this subpart if water is
delivered from the wholesale system to
the consecutive system for at least 60
consecutive days through any of the
consecutive system entry points. A
consecutive system that buys all its
finished water during the period
identified in this paragraph must
monitor based on population and source
water for the purpose of determining
monitoring requirements of this subpart.
(i) You may request that the State
allow multiple consecutive system entry
points from a single wholesale system to
a single consecutive system to be
considered one treatment plant.
(ii) In the request to the State for
approval of multiple consecutive system
entry points to be considered one
treatment plant, you must demonstrate
that factors such as relative locations of
entry points, detention times, sources,
and the presence of treatment (such as
corrosion control or booster
disinfection) will have a minimal
differential effect on TTHM and HAAS
formation associated with individual
entry points.
§141.602 IDSE monitoring.
(a) You must conduct IDSE
monitoring for each treatment plant as
indicated in the table in this paragraph.
You must collect dual sample sets at
each monitoring location. One sample
in the set must be analyzed for TTHM.
The other sample in the set must be
analyzed for HAAS. If approved by the
State under the provisions of
§ 141.601(d)(lJ, you may consider
multiple wells drawing water from the
same aquifer to be one treatment plant
for the purpose of determining
monitoring requirements. You must
conduct one monitoring period during
the peak historical month for TTHM
levels or HAAS levels or the month of
warmest water temperature. You must
review available compliance, study, or
operational data to determine the peak
historical month for TTHM or HAAS
levels or warmest water temperature.
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49673
If you are this type of system
Then you must monitor
At these locations for each treatment plant
(1) Subpart H serving >10,000
(2) Subpart H serving 500-
9,999.
(3) Subpart H serving <500
(4) Ground water serving
>10,000.
(5) Ground water serving <
10,000.
(6) Consecutive system
Approximately every 60 days for one year (six
monitoring periods).
Approximately every 90 days for one year
(four monitoring periods).
Approximately every 180 days for one year
(two monitoring periods).
Approximately every 90 days for one year
(four monitoring periods).
Approximately every 180 days for one year
(two monitoring periods).
At a frequency based on source water and
your population3.
Eight dual sample sets per monitoring period at locations
other than subpart L TTHM/HAA5 monitoring locations
based on conditions:
If CHLORINE is used as residua! disinfectant: one near dis-
tribution system entry point, two at average residence time,
five at points representative of highest expected TTHM
(three sites) and HAAS concentration (two sites).
If CHLORAMINE is used as residual disinfectant for any part
of the year: two near distribution system entry point, two at
average residence time, four at points representative of
highest expected TTHM (two sites) and HAAS concentra-
tion (two sites).
Two dual sample sets per monitoring period at locations other
than the for one year subpart L TTHM/HAA5 monitoring lo-
cation; one each representative of expected high periods)
TTHM level and HAAS level.
Two dual sample sets per monitoring period at locations other
than the subpart L TTHM/HAA5 monitoring location; one
each representative of expected .high periods) TTHM level
and HAAS level.
Two dual sample sets per monitoring period at locations other
than the subpart L TTHM/HAA5 monitoring location; one
each representative of expected high periods) TTHM level
and HAAS level.
Two dual sample sets per monitoring period at locations other
than the subpart L TTHM/HAA5 monitoring location; one
each representative of expected high periods) TTHM level
and HAA5 level.
—For a consecutive system that buys all its finished water,
number of samples and locations as specified in paragraph
(b) of this section.
—For a consecutive system that buys some, but not all, of its
finished water, serves >10,000, and receives water from a
subpart H system: at IDSE locations required of a subpart
H system serving >10,000.
—For a consecutive system that does not meet any other cri-
teria in this paragraph: two dual sample sets per monitoring
period at locations other than the subpart L TTHM/HAA5
compliance monitoring location; one each representative of
expected high TTHM levels and HAAS levels.
11ncluding treatment plants for consecutive system entry points that operate for at least 60 consecutive days.
2The State may require additional monitoring.
3You must monitor at the frequency required of a subpart H system with your population if you deliver any water required to be treated under
subpart H. You must monitor at the frequency required of a ground water system with your population if you deliver no water required to be treat-
ed under subpart H.
(b) IDSE monitoring for consecutive
systems that buy all their water.
IDSE MONITORING LOCATIONS FOR CONSECUTIVE SYSTEMS THAT BUY ALL THEIR WATER
Population category
Number of
dual sample
set locations
per moni-
toring period
Distribution system dual sample set locations 1
Near entry
points2
Average
residence
time
Highest
TTHM
locations
Highest
HAAS
locations
Subpart H Consecutive Systems that buy all their water
<5003
500 .to 4 9994
5 000 to 9,9994
10 000 to 24,999s
25 000 to 49,999s
50 000 to 99,9995
100 000 to 499 999s
500,000 to 1,499,999s
1 500 000 to 4,999,9995
>-50000005
2
2
4
8
12
16
24
32
40
48
1
2
3
4
6
8
10
1
2
3
4
6
8
10
12
1
1
2
3
4
5
8
10
12
14
1
1
1
2
3
4
6
8
10
12
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Federal Register/VoI. 68, No. 159/Monday, August 18, 2003/Proposed Rules
IDSE MONITORING LOCATIONS FOR CONSECUTIVE SYSTEMS THAT BUY ALL THEIR WATER—Continued
Population category
Number of
dual sample
set locations
per moni-
toring period
Distribution system dual sample set locations 1
Near entry
points2
Average
residence
time
Highest
TTHM
locations
Highest
HAAS
locations
Ground Water Consecutive Systems that buy all their water
<5003
500to9,9994
10,000 to 99,9994
100,000 to 499,999"
>500,0004
2
2
6
8
12
1
1
2
1
2
1
1 Sampling locations to be distributed through distribution system. You may not use subpart L compliance monitoring locations as IDSE sample
sites. You must collect a dual sample set at each sample location.
2 If the actual number of entry points to the distribution system is fewer than the specified number of "near entry point" sampling sites, take ad-
ditional samples equally at highest TTHM and HAA5 locations. If there is an odd extra location number, take the odd sample at highest TTHM lo-
cation. If the actual number of entry points to the distribution system is more than the specified number of sampling locations, take samples first
at subpart H entry points to the distribution system having the highest water flows and then at ground water entry points to the distribution sys-
tem having the highest water flows.
3 You must conduct monjtoring during two monitoring periods approximately 180 days apart.
4 You must conduct monitoring during four monitoring periods approximately 90 days apart.
5 You must conduct monitoring during six monitoring periods approximately 60 days apart.
(c) You must prepare an IDSE
monitoring plan prior to starting IDSE
monitoring and implement that plan. In
the plan, you must identify specific
monitoring locations and dates that
meet the criteria in paragraphs (a) and
(b) of this section, as applicable.
§ 141.603 Alternatives other than IDSE
monitoring.
In lieu of IDSE monitoring under
§ 141.602, you may use one of the
alternatives identified in paragraphs (a)
through (c) of this section for which you
qualify to comply with this subpart.
(a) System-specific study. You may
perform an IDSE study based on system-
specific monitoring or system-specific
data if such a study identifies equivalent
or superior monitoring sites
representing high TTHM and HAAS
levels as would be identified by IDSE
monitoring under § 141.602. You must
submit an IDSE report that complies
with §141.604.
(b) 40/30 certification. In order to
qualify for the 40/30 certification, you
must not have had any TTHM or HAAS
monitoring violations during the
periods specified in paragraphs (b)(l)
through (b}(3) of this section.
(1) You are not required to comply
with § 141.602 or paragraph (a) of this
section if you certify to your State that
all compliance samples under subpart L
in 2002 and 2003 (for subpart H systems
serving 510,000 people) or in 2004 and
2005 (for systems serving <10,000
people that are not required, to submit
an IDSE report by [date 24 months
following publication of final rule])
were <0.040 mg/L for TTHM and <0.030
mg/L for HAAS.
(2) If you are a ground water system
serving £10,000 people, you are not
required to comply with § 141.602 or
paragraph (a) of this section if you
certify to your State that all TTHM
samples taken under § 141.30 in 2003
are <0.040 mg/L and that all TTHM and
HAAS compliance samples taken under
subpart L during 2004 are <0.040 mg/L
and £0.030 mg/L, respectively.
(3) If you are a consecutive system
serving <10,000 required to submit an
IDSE report by [date 24 months
following publication of final rule], you
are not required to comply with
§ 141.602 or paragraph (a) of this section
ifyou certify to your State that all
TTHM and HAAS compliance samples
taken under subpart L during 2004 are
<0.040 mg/L and £0.030 mg/L,
respectively.
(4) You must submit an IDSE report
that complies with § 141.604 and
contains the required certification.
(c) Very small system waiver. If you
serve fewer than 500 people, the State
may waive IDSE monitoring if the State
determines that the TTHM and HAAS
monitoring site for each plant under
§ 141.132 is sufficient to represent both
the highest TTHM and the highest
HAAS concentration in your
distribution system. If your IDSE
monitoring is waived, you are not
required to submit an IDSE report. You
must monitor under subpart V during
the same month and at the same
location as used for compliance
sampling in subpart L.
§141.604 IDSE reports.
You must submit your IDSE report to
the State according to the schedule in
§141.600(c).
(a) Ifyou complied by meeting the
provisions of §§ 141.602 or 141.603(a),
your IDSE report must include the
elements required in paragraphs (a)(l)
through (a}(3) of this section.
(1) Your report must include all
TTHM and HAAS analytical results
from subpart L compliance monitoring
conducted during the period of the IDSE
presented in a tabular or spreadsheet
format acceptable to the State. Your
report must also include a schematic of
your distribution system, with results,
location, and date of all IDSE
monitoring, system-specific study
monitoring, and subpart L compliance
samples noted.
(2) If you conducted IDSE monitoring
under § 141.602, your report must
include all IDSE TTHM and HAAS
analytical results presented in a tabular
or spreadsheet format acceptable to the
State. Your report must also include all
additional data you relied on to justify
IDSE monitoring site selection, plus
your original monitoring plan
developed under § 141.602(c) and an
explanation of any deviations from that
plan.
(3) Ifyou used the system-specific
study alternative in § 141.603(a), your
report must include the basis (studies,
reports, data, analytical results,
modeling) by which you determined
that the recommended subpart V
monitoring sites representing high
TTHM and HAAS levels are comparable
or superior to those that would
otherwise have been identified by IDSE
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49675
monitoring under § 141.602. Your report
must-also include an analysis that
demonstrates that your system-specific
study characterized expected TTHM
and HAAS levels throughout your entire
distribution system.
(b) If you meet the 40/30 certification
criteria in § 141.603(b), your IDSE report
must include all TTHM and HAAS
analytical results from compliance
monitoring used to qualify for the 40/30
certification and a schematic of your
distribution system {with results,
location, and date of all compliance
samples noted). You must also include
results of those compliance samples
taken after the period used to qualify for
the 40/30 certification for State review.
(c) Your IDSE report must include
your recommendations and justification
for where and during what month(s)
TTHM and HAAS monitoring for
Subpart V should be conducted. You
must base your recommendations on the
criteria in § 141.605. Your IDSE report
must also include the population
served; system type (subpart H or
ground water); whether your system is
a consecutive system; and, if you
conducted plant-based monitoring, the
number of treatment plants and
consecutive system entry points.
(d) Recordkeeping. You must retain a
complete copy of your IDSE report
submitted under § 141.604 for 10 years
after the date that you submitted your
IDSE report. If the'State modifies the
monitoring requirements that you
recommended in your IDSE report or if
the State approves alternative
monitoring sites, you must keep a copy
of the State's notification on file for 10
years after the date of the State's
notification. You must make the IDSE
report and any State notification
available for review by the State or the
public.
§141.605 Subpart V monitoring location
recommendations to the State.
(a) Subpart H systems serving at least
10,000 people. If you are a system
required to take four dual sample sets
per treatment plant per quarter under
routine monitoring under § 141.621, you
must base your recommendations on the
locations in the distribution system
where you expect to find the highest
TTHM and'HAAS LRAAs. In
determining the highest LRAA, you
must evaluate both subpart L
compliance data and IDSE data. For
each plant, you must recommend
locations with:
(1) The two highest TTHM locational
running annual averages;
(2) The highest HAAS locational
running annual average; and
(3) An existing subpart L compliance
monitoring location identified in the
§ 141.132(f) monitoring plan that is the
location of either the highest TTHM or
HAAS LRAA among the three
compliance monitoring locations
representative of average residence time
(by calculating an LRAA for each
compliance monitoring location using
the compliance monitoring results
collected during the period'of the IDSE).
(4) You may recommend locations
other than those in paragraphs (a)(l)
through (3) of this section if you include
a rationale for selecting other locations.
If the State approves, you must monitor
at these locations to determine
compliance under subpart V.
(5) If any of the criteria in this
paragraph (a) of this section would
cause fewer than four locations per
treatment plant to be recommended, you
must identify an additional location(s)
with the next highest HAAS LRAA.
(b) All grounawater systems and
subpart H systems serving.fewer than
10,000 people. If you are a system
required to take two dual sample sets
per treatment plant per quarter or per
year or one TTHM and one HAAS
sample per plant per year for routine
monitoring under § 141.621, you must
select the locations with the highest
TTHM locational running annual
average and highest HAAS locational
running annual average, unless you
include a rationale for selecting other
locations. If the State approves, you
must monitor at these other locations to
determine compliance under subpart V.
If any of the criteria in this paragraph
would cause only one location per
treatment plant to be recommended, you
must identify an additional location
with the next highest HAAS LRAA or
request that you be allowed to monitor
only at that location.
(c) Systems that qualify for the 40/30
certification. If you use the 40/30
certification in § 141.603(b), you may
use either subpart L compliance
monitoring locations or you may
identify monitoring locations for
Subpart V that are different from those
for subpart L. You must include a
rationale for changing existing subpart L
locations, choosing locations with a
long residence time and a detectable
residual. If you choose monitoring
locations other than those in subpart L
as subpart V compliance monitoring
locations, you must retain the subpart L
locations with the highest TTHM and
HAAS LRAAs. If any of the criteria in
this paragraph would cause only one
location per treatment plant to be
recommended, you must identify an
additional location with the next
highest HAAS LRAA or request that you
be allowed to monitor only at that
location. If you are required to monitor
at more locations under subpart V of
this part than under subpart L of this
part, you must identify additional
locations with a long residence time and
a detectable residual.
(d) Consecutive systems that buy
some, but not all, of their finished water.
Your recommendations must comply
with §§ 141.601(d) and 141.605 (a)
through (c).
(e) Consecutive systems that buy all
their finished water.
(I) You must select the number of
monitoring locations specified in the
following tables.
SUBPART V.—SAMPLE FREQUENCY FOR TTHM/HAA5 (AS DUAL SAMPLE SETS) FOR CONSECUTIVE SYSTEMS THAT BUY
ALL THEIR WATER
Population
Number of samples
Subpart H Consecutive Systems That Buy AM Their Water
<500
500 to 4,999
5,000 to 9,999 ...
10,000 to 24,999
25,000 to 49,999
50,000 to 99,999
1 TTHM and 1 HAAS sample per year at different locations and time if the highest TTHM and HAAS occurred at
different locations and/or time or 1 dual sample set per year if the highest TTHM and HAAS occurred at the
same location and time of year, taken during the peak historical month for DBP concentrations or (if unknown)
month of warmest water temperature.
1 TTHM and 1 HAAS sample per quarter at different locations if the highest TTHM and HAAS occurred at different
locations or 1 dual sample set per quarter if the highest TTHM and HAAS occurred at the same location.
2 dual sample sets per quarter.
4 dual sample sets per quarter.
6 dual sample sets per quarter.
8 dual sample sets per quarter.
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Federal Register/Vol. G6. No. 159/Monday, August 18, 2003/Proposed Rules
SUBPART V.-
-SAMPLE FREQUENCY FOR TTHM/HAA5 (AS DUAL SAMPLE SETS) FOR CONSECUTIVE SYSTEMS THAT BUY
ALL THEIR WATER—Continued
Population
Number of samples
100,000 to 499,999
500,000 to 1,499,999 ..
1,500,000 to 4,999.999
>=5,000,000
12 dual sample sets per quarter.
16 dual sample sets per quarter.
20 dual sample sets per quarter.
24 dual sample sets per quarter.
Ground Water Consecutive Systems That Buy All Their Water
<500
500 to 9,999
10,000 to 99,999 ...
100,000 to 499,999
>500,000
1 TTHM and 1 HAAS sample per year at different locations and time if the highest TTHM and HAAS occurred at
different locations and/or time or 1 dual sample set per year if the highest TTHM and HAA5 occurred at the
same location and time of year, taken during the peak historical month for DBF concentrations, or, if unknown,
during month of warmest water temperature.
2 dual sample sets per year. Must be taken during the peak historical month for DBP concentrations.
4 dual sample sets per quarter.
6 dual sample sets per quarter.
8 dual sample sets per quarter.
(2) You must select Subpart V
monitoring locations based on subpart L
compliance monitoring results collected
during the period of the IDSE and IDSE
monitoring results. You must follow the
protocol in paragraphs (e)(2)(i) through
(iv) of this section, unless you provide
a rationale for recommending different
locations. If required to monitor at more
than four locations, you must repeat the
protocol as necessary, alternating
between sites with the highest HAA5
LRAA and the highest TTHM LRAA not
previously selected as a subpart V
monitoring location for choosing
locations under paragraph (e)(2)(iii) of
this section.
(i) Location with the highest TTHM
LRAA not previously selected as a
subpart V monitoring location.
(ii) Location with the highest HAAS
LRAA not previously selected as a
subpart V monitoring location.
(iii) Existing subpart L average
residence time compliance monitoring
location.
(iv) Location with the highest TTHM
LRAA not previously selected as a
subpart V monitoring location.
(3) You may recommend locations
other than those in paragraph (e)(2) of
this section if you include a rationale for
selecting other locations. If the State
approves, you must monitor at these
locations to determine compliance
under subpart V.
(4) If you used the 40/30 certification
in § 141.603(b) and do not have
sufficient subpart L monitoring
locations to identify the required
number of Subpart V compliance
monitoring locations, you must identify
additional locations by selecting a site
representative of maximum residence
time and then a site representative of
average residence time and repeating
until the required number of
compliance monitoring locations have
been identified.
(f) You must schedule samples during
the peak historical month for TTHM and
HAAS concentration, unless the State
approves another month. Once you have
identified the peak historical month,
and if you are required to conduct
routine monitoring at least quarterly,
you must schedule subpart V
compliance monitoring at a regular
frequency of approximately every 90
days or fewer.
18. Part 141 is amended by adding
new subpart V to read as follows:
Subpart V—Stage 2B Disinfection
Byproducts Requirements
Sec.
141.620 General requirements.
141.621 Routine monitoring.
141.622 Subpart V monitoring plan.
141.623 Reduced monitoring.
141.624 Additional requirements for
consecutive systems.
141.625 Conditions requiring increased
monitoring.
141.626 Significant excursions.
141.627 Requirements for remaining on
reduced TTHM and HAA5 monitoring
based on subpart L results.
141.628 Requirements for remaining on
increased TTHM and HAAS monitoring
based on subpart L results.
141.629 (Reserved]
141.630 Reporting and recordkeeping
requirements.
Subpart V—Stage 2B Disinfection
Byproducts Requirements
§ 141.620 General requirements.
(a) The requirements of subpart V
constitute national primary drinking
water regulations. These regulations
establish requirements for control of
certain disinfection byproducts that
supercede some requirements in subpart
L and that are in addition to other
requirements that are currently required
under subpart L of this part. The
regulations in this subpart establish
monitoring and other requirements for
achieving compliance with maximum
contaminant levels for total
trihalomethanes (TTHM) and haloacetic
acids (five)(HAA5).
(b) Applicability. You are subject to
these requirements if your system is a
community water system or
nontransient noncommunity water
system that adds a primary or residual
disinfectant other than ultraviolet light
or delivers water that has been treated
with a primary or residual disinfectant
other than ultraviolet light.
(c) Schedule. You must comply with
the requirements in this subpart on the
schedule in the following table, based
on your system type.
If you are this type of system
You must comply with subpart V by:123
(1) Subpart H serving >10,000
(2) Subpart H serving $10,000
(3) Ground water serving >10,000
(4) Ground water serving <10,000
[date 72 mos following publication of final rule].
[date 90 mos following publication of final rule] if no Cryptosporidium monitoring is required
under §141.706(c) OR
[date 102 mos following publication of final rule] if Cryptosporidium monitoring is required
under § 141.706(c).
[date 72 mos following publication of final rule].
[date 90 mos following publication of final rule].
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
49677
If you are this type of system
tion system.
You must comply with subpart V by: 1 2 3
1 The State may grant up to an additional 24 months for compliance if you require capital improvements.
2 If you are required to conduct quarterly monitoring, you must begin monitoring in the first full calendar quarter that follows the compliance
date in this table. If you are required to conduct monitoring at a frequency that is less than quarterly, you must begin monitoring in the calendar
month recommended in the IDSE report prepared under §141.604 no later than 12 months after the compliance date in this table. tf you are not
required to submit an IDSE report, you must begin monitoring during the calendar month identified in the monitoring plan developed under
§141.622 no later than 12 months after the compliance date.
3 tf you are required to conduct quarterly monitoring, you must make compliance calculations at the end of the fourth calendar quarter that fol-
lows the compliance date and at the end of each subsequent quarter (or earlier if the LRAA calculated based on fewer than four quarters of data
would cause the MCL to be exceeded regardless of the monitoring results of subsequent quarters). If you are required to conduct monitoring at a
frequency that is less than quarterly, you must make compliance calculations beginning with the first compliance sample taken after the compli-
ance date.
(d) Monitoring and compliance. You
must monitor at sampling locations
identified in your monitoring plan
developed under §141.622. To
determine compliance with subpart V
MCLs, you must calculate locational
running annual averages for TTHM and
HAAS using monitoring results
collected under this subpart. If you fail
to complete four consecutive quarters of
monitoring, you must calculate
compliance with the MCL based on an
average of the available data from the
most recent four quarters.
(e) Violations. You must comply with
specific monitoring and reporting
requirements. Failure to monitor in
accordance with the monitoring plan
required under § 141.622 is a
monitoring violation. Failure to monitor
will also be treated as a monitoring
violation for the entire period covered
by a locational running annual average
compliance calculation for the subpart
VMCLsin§141.64(b)(3).
(f) Additional provisions.
• (1) You may consider multiple wells
drawing water from a single aquifer as
one treatment plant for determining the
minimum number of TTHM and HAAS
samples required, with State approval in
accordance with criteria developed
under § 142.16(h)(5) of this chapter.
Approvals made under §§ 141.132(a)(2)
and 141.601(d) remain in effect unless
withdrawn by the State.
(2) Consecutive systems. For the
purposes of this subpart, you must
determine whether you buy all or some
of your water based on your
categorization for the IDSE under
subpart U, unless otherwise directed by
the State. If you were not categorized
under subpart U, you must determine
whether you buy all or some of your
water based on your categorization
during 2005, unless otherwise directed
by the State.
(3) For the purposes of determining
monitoring requirements of this subpart,
each consecutive system entry point
from a wholesale system to a
consecutive system that buys some, but
not all, of its finished water is
considered a treatment plant for that
consecutive system.
(i) You may request that the State
allow multiple consecutive system entry
points from a single wholesale system to
a single consecutive system to be
considered one treatment plant.
(ii) In the request to the State for
approval of multiple consecutive system
entry points to be considered one
treatment plant, you must demonstrate
that factors such as relative locations of
entry points, detention times, sources,
and the presence of treatment (such as
corrosion control or booster
disinfection) will have a minimal
differential effect on TTHM and HAAS
formation associated with individual
entry points.
§141.621 Routine monitoring.
(a) You must monitor at the locations
and frequencies listed in the following
table.
If you are this type of
system
Then you must monitor
At these locations for each treatment plant
(1) Subpart H serving
>10,000.
(2) Subpart H serving 500-
9,999.
(3) Subpart H serving <500
(4) Ground water serving
£10,000.
[5) Ground water serving
500-9,999.
|6) Ground water serving
<500.
7) Consecutive system that
buys some, but not all, of
its finished water.
four dual sample sets per quarter per treatment plant,
taken approximately every 90 days. One quarterly set
must be taken during the peak historical month for
DBP concentrations 2.
two dual sample sets per quarter per treatment plant,
taken approximately every 90 days. One quarterly set
must be taken during the peak historical month for
DBP concentrations 2.
one TTHM and one HAA5 sample per year per treat-
ment plant, taken during the peak historical month for
DBP concentrations.
two dual sample sets per quarter per treatment plant,
taken approximately every 90 days. One quarterly set
must be taken during the peak historical month for
DBP concentrations 2.
two dual sample sets per year per treatment plant,
taken during the peak historical month for DBP con-
centrations 2.
one TTHM and one HAA5 sample per year per treat-
ment plant, taken during the peak historical month for
DBP concentrations.
based on your own population and source water, ex-
cept that consecutive systems that receive water from
a subpart H system must monitor as a subpart H sys-
tem.
-locations recommended to the State in the IDSE re-
port submitted under subpart U.
—locations recommended to the State in the IDSE re-
port submitted under subpart U.3
—locations recommended to the State in the IDSE re-
port submitted under subpart U.4
—locations recommended to the State in the IDSE re-
port submitted under subpart U.3
—locations recommended to the State in the IDSE re-
port submitted under subpart U.3
—locations recommended to the State in the IDSE re-
port submitted under subpart U.4.
—locations recommended to the State in the IDSE re-
port submitted under subpart U.
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Federal Register /Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
If you are this type of
system
buys all its finished water.
Then you must monitor
as specified in §141.605(e)
At these locations for each treatment plant1
port submitted under subpart U.
1 Unless the State has approved or required other locations or additional locations based on the IDSE report or other information, or you have
updated the monitoring plan under §141.622.
2 A dual sample set is a set of two samples collected at the same time and same location, with one sample analyzed for TTHM and the other
sample analyzed for HAAS.
3 If you have a single location that has both the highest TTHM LRAA and highest HAAS LRAA, you may take a dual sample set only at that lo-
cation after approval by the State.
4You are required to sample for both TTHM and HAA5 at one location if that location is the highest for both TTHM and HAAS. If different loca-
tions have high TTHM and HAAS LRAAs, you may sample for TTHM only at the high TTHM location and for HAAS only at the high HAAS loca-
tion. If you have received a very small system waiver for IDSE monitoring from the State under §141.603(c), you must monitor for TTHM and
HAAS as a dual sample set at the subpart L monitoring location (a point representative of maximum residence time) during the month of warmest
water temperature.
(b) You must begin monitoring at the
locations you have recommended in
your IDSE report submitted under
§ 141.604 following the schedule in
§ 141.620(c), unless the State requires
other locations or additional locations
after its review. If you have received a
very small system waiver under
§141.603(c), you must monitor at the
location(s) identified in your monitoring
plan in § 141.132(f), updated as required
by §141.622.
(c) You must use an approved method
listed in §141.131 for TTHM and HAAS
analyses in this subpart. Analyses must
be conducted by laboratories that have
received certification by EPA or the
State as specified in §141.131.
§ 141.622 Subpart V monitoring plan.
(a) You must develop and implement
a monitoring plan to be kept on file for
State and public review. You may
comply by updating the monitoring plan
developed under § 141.132(f) no later
than the date identified in § 141.620(c)
for subpart V compliance. If you have
received a very small system waiver
under § 141.603(c), you must comply by
updating the monitoring plan developed
under §141.132(0 no later than the date
identified in § 141.620(c) for subpart V
compliance. The monitoring plan must
contain the elements in paragraphs
(a)(l) through (a)(5) of this section:
(1) Monitoring locations;
(2) Monitoring dates;
(3) Compliance calculation
procedures;
(4) Monitoring plans for any other
systems in the combined distribution
system if monitoring requirements have
been modified based on data from other
systems; and
(5) Any permits, contracts, or
agreements with third parties (including
other PWSs, laboratories, and State
agencies) to sample, analyze, report, or
perform any other system requirement
in this subpart.
(b) The monitoring plan will reflect
the recommendations of the IDSE report
required under subpart U, along with
any State-mandated modifications. The
State must approve any monitoring sites
for which you are required to provide a
rationale in your IDSE report by
§141.605(a)(4).
(c) If you are a subpart H system
serving more than 3,300 people, you
must submit a copy of your monitoring
plan to the State prior to the date you
are required to comply with the
monitoring plan.
(d) You may modify your monitoring
plan to reflect changes in treatment,
distribution system operations and
layout (including new service areas), or
other factors that may affect TTHM or
HAAS formation. If you change
monitoring locations, you must replace
locations with the lowest LRAA and
notify the State how new sites were
selected as part of the next report due
under § 141.630. The State may also
require modifications in your
monitoring plan.
§141.623 Reduced monitoring.
(a) Systems other than consecutive
systems that buy ail their water. You
may reduce monitoring by meeting the
criteria in the table in this paragraph at
all treatment plants in the system. You
may only use data collected under the
provisions of this subpart or subpart L
of this part to qualify for reduced
monitoring.
If you are this type of
system
Then you may reduce monitoring if you have
monitoring results under § 141.621 and
To reduce monitoring per plant at these locations/frequency
TTHM
HAAS
(1) Subpart H serving
>10,000.
(2) Subpart H serving
500-9,999.
(3) Subpart H serving
<500.
(4) Ground water serv-
ing £10,000.
—the LRAA is <0.040 mg/L for TTHM and
£0.030 for HAAS at ALL monitoring loca-
tions, AND
—the source water annual average TOC
level, before any treatment, is £4.0 mg/L at
each subpart H treatment plant1.
—the LRAA is £0.040 mg/L for TTHM and
£0.030 for HAAS at ALL monitoring loca-
tions, AND
—the source water annual average TOC
level, before any treatment, is £4.0 mg/L at
each subpart H treatment plant1.
—monitoring may not be reduced to fewer
than one TTHM sample and one HAAS
sample per year.
—the LRAA is £0.040 mgA. for TTHM and
£0.030 for HAAS at ALL monitoring loca-
tions.
—monitor once per quarter by taking a dual
sample set at the location with the highest
TTHM LRAA or single measurement.
—monitor once per year by taking a dual
sample set at the location with the highest
TTHM single measurement during the
quarter that the highest single TTHM
measurement occurred2.
not applicable
—monitor once per year by taking a dual
sample set at the location with the highest
TTHM single measurement during the
quarter that the highest single TTHM
measurement occurred 2.
-monitor once per quarter by taking a dual
sample set at the location with the highest
HAAS LRAA or single measurement.
-monitor once per year by taking a dual
sample set at the location with the highest
HHA5 single measurement during the
quarter that the highest single HHA5
measurement occurred.2
not applicable.
—monitor once per year by taking a dual
sample set at the location with the highest
HHA5 single measurement during the
quarter that the highest single HHA5
measurement occurred.2
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49679
If you are this type of
system
Then you may reduce monitoring if you have
monitoring results under §141.621 and
To reduce monitoring per plant at these locations/frequency
TTHM
HAAS
(5) Ground water serv-
ing 500-9,999.
(6) Ground water serv-
ing <500.
(7) Consecutive sys-
tem that buys some,
but not all, of its fin-
ished water3.
-the LRM is £0.040 mg/L for TFHM and
£0.030 for HAAS at ALL monitoring loca-
tions.
—the LRAA is £0.040 mg/L for TTHM and
£0,030 for HAAS at ALL monitoring loca-
tions.
—the LRAA is £0.040 mg/L for TTHM and
S0.030 for HAA5 at ALL monitoring loca-
tions.
—monitor once every third year by taking a
dual sample set at the location with the
highest TTHM single measurement during
the quarter that the highest single TTHM
measurement occurred3.
—monitor once every third year for TTHM at
the location with the highest TTHM single
measurement during the quarter that the
highest single TTHM measurement oc-
curred2.
—monitor at the location(s) and frequency
associated with a non-consecutive system
with the same population and source water
type.
—monitor once every third year by taking a
dual sample set at the location with the
highest HHA5 single measurement during
the quarter that the highest single HHA5
measurement occurred.2
—monitor once every third year for HAAS at
the location with the highest HAAS single
measurement during the quarter that the
highest single HAAS measurement oc-
curred.2
—monitor at the location(s) and frequency
associated with a non-consecutive system
with the same population and source water
type.2
'TOG monitoring must comply with the provisions of either §141.132(d) or §141.132(e).
2 If your location for reduced monitoring for TTHM and HAA5 is the same location and if your quarter for the highest TTHM and HAA5 single measurement is the
same, you may take one dual sample set at that location during that quarter.
3 Consecutive systems that buy some, but not all, of their finished water may reduce monitoring based on their own population and their wholesale system(s)'s
source water type to the frequency and location(s) required in this section, unless the consecutive system treats surface water or ground water under the direct influ-
ence of surface water. If the consecutive system treats surface water or ground water under the direct influence of surface water, it must base reduced monitoring on
its population and classification as a subpart H system.
fb) Consecutive systems that buy all
their water. You may reduce monitoring
to the level specified in the table in this
paragraph if the LRAA is <0.040 mg/L
for TTHM and <0.030 mg/L for HAAS at
all monitoring locations. You may only
use data collected under the provisions
of this subpart or subpart L of this part
to qualify for reduced monitoring.
REDUCED MONITORING FREQUENCY FOR CONSECUTIVE SYSTEMS THAT BUY ALL THEIR WATER.
Population
Reduced monitoring frequency and location
Subpart H systems
<500 Monitoring may not be reduced.
500 to 4,999 1 TTHM and 1 HAAS sample per year at different locations or during different quarters if the highest TTHM and
HAA5 measurements occurred at different locations or different quarters or 1 dual sample set per year if the
highest TTHM and HAAS measurements occurred at the same location and quarter.
5,000 to 9,999 2 dual sample sets per year; one at the location with the highest TTHM single measurement during the quarter
that the highest single TTHM measurement occurred, one at the location with the highest HAAS single meas-
urement during the quarter that the highest single HAAS measurement occurred.
10,000 to 24,999 2 dual sample sets per quarter at the locations with the highest TTHM and highest HAA5 LRAAs.
25,000 to 49,999 2 dual sample sets per quarter at the locations with the highest TTHM and highest HAAS LRAAs.
50,000 to 99,000 4 dual sample sets per quarter—at the locations with the two highest "TTHM and two highest HAAS LRAAs.
100,000 to 499,999 4 dual sample sets per quarter—at the locations with the two highest TTHM and two highest HAAS LRAAs.
500,000 to 1,499,999 6 dual sample sets per quarter—at the locations with the three highest TTHM and three highest HAAS LRAAs.
1,500,000 to 4,999,999 6 duat sample sets per quarter—at the locations with the three highest TTHM and three highest HAAS LRAAs.
>=5,000,000 8 dual sample sets per quarter at the locations with the four highest TTHM and four highest HAAS LRAAs.
Ground water systems
<500 1 TTHM and 1 HAAS sample every third year at different locations and time if the highest TTHM and HAAS
measurements occurred at different locations and/or time or 1 dual sample set every third year if the highest
TTHM and HAAS measurements occurred at the same location and time of year.
500 to 9,999 1 TTHM and 1 HAAS sample every year at different locations and time if the highest TTHM and HAAS meas-
urements occurred at different locations and/or time or 1 dual sample set every year if the highest TTHM and
HAAS measurements occurred at the same location and time of year.
10,000 to 99,000 2 dual sample sets per year; one at the location with the highest TTHM single measurement during the quarter
that the highest single TTHM measurement occurred and one at the location with the highest HAA5 single
measurement during the quarter that the highest single HAAS measurement occurred.
100,000 to 499,999 2 dual sample sets per quarter; at the locations with the highest TTHM and highest HAAS LRAAs.
>500,000 4 dual sample sets per quarter; at the locations with the two highest TTHM and two highest HAAS LRAAs.
(c) You may remain on reduced
monitoring as long as the TTHM LRAA
£0.040 mg/L and the HAA5 LRAA
<0.030 mg/L at each monitoring location
'for systems with quarterly monitoring)
3r each TTHM sample <0.060 mg/L and
ach HAAS sample <0.045 mg/L (for
systems with annual or less frequent
monitoring). In addition, the source
water annual average TOG level, before
any treatment, must be <4.0 mg/L at
each treatment plant treating surface
water or ground water under the direct
influence of surface water, based on
monitoring conducted under either
§§141.132(d) or 141.132(e). If the LRAA
at any location exceeds either 0.040 mg/
L for TTHM or 0.030 mg/L for HAAS or
if the annual (or less frequent) sample
at any location exceeds either 0.060 mg/
L for TTHM or 0.045 mg/L for HAAS,
or if the source water annual average
TOG level, before any treatment, >4.0
mg/L at any treatment plant treating
surface water or ground water under the
direct influence of surface water, the
system must resume routine monitoring
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
under § 141.621 for all treatment plants
or begin increased monitoring for all
treatment plants if § 141.625 applies.
(d) The State may return your system
to routine monitoring at the State's
discretion.
§ 141.624 Additional requirements for
consecutive systems.
If you are a consecutive system that
does not add a disinfectant but delivers
water that has been disinfected with
other than ultraviolet light, you must
comply with monitoring requirements
for chlorine and chloramines in
§ 141.132(c)(l) and the compliance
requirements in § 141.133(c)(l)
beginning [date three years after
publication Of final rule] and report
monitoring results under §141.134(c),
unless required earlier by the State.
§ 141.625 Conditions requiring increased
monitoring.
(a) If you are required to monitor at
a particular location yearly or less
frequently than yearly under §§ 141.621
or 141.623, you must increase
monitoring to dual sample sets once per
quarter (taken approximately every 90
days) at all locations if either the annual
(or less frequent) TTHM sample >0.080
mg/L or the annual (or less frequent)
HAA5 sample >0.060 mg/L at any
location.
(b) You are not in violation of the
MCL until the LRAA calculated based
on four consecutive quarters of
monitoring (or the LRAA calculated
based on fewer than four quarters of
data if the MCL would be exceeded
regardless of the monitoring results of
subsequent quarters) exceeds the
subpart V MCLs in § 141.64(b)(3). You
are in violation of the monitoring
requirements for each quarter that a
monitoring result would be used in
calculating an LRAA if you fail to
monitor.
(c) You may return to routine
monitoring once you have conducted
increased monitoring for at least four
consecutive quarters and the LRAA for
every location is <0,060 mg/L for TTHM
and <0.045 mg/L for HAAS.
§141.626 Significant excursions.
If a significant excursion occurs, you
must conduct a significant excursion
evaluation and prepare a written report
of the evaluation no later than 90 days
after being notified of the analytical
result that shows the significant
excursion. You must discuss the
evaluation with the State no later than
the next sanitary survey for your system.
Your evaluation must include an
examination of distribution system
operational practices that may
contribute to TTHM and HAAS
formation (such as flushing programs
and storage tank operations and excess
capacity) and how these practices may
be modified to reduce TTHM and HAAS
levels.
§ 141.627 Requirements for remaining on
reduced TTHM and HAAS monitoring based
on subpart L results.
You may remain on reduced
monitoring after the dates identified in
§ 141.620(c) for compliance with this
subpart only if you qualify for a 40/30
certification under § 141.603(b) or have
received a very small system waiver
under § 141.603(c), plus you meet the
reduced monitoring criteria in
§ 141.623(c), and you do not change or
add monitoring locations from those
used for compliance monitoring under
subpart L. If your monitoring locations
under this subpart differ from your
monitoring locations under subpart L,
you may not remain on reduced
monitoring after the dates identified in
§ 141.620(c) for compliance with this
subpart.
§ 141.628 Requirements for remaining on
increased TTHM and HAAS monitoring
based on subpart L results.
If you were on increased monitoring
under subpart L, you must remain on
increased monitoring until you qualify
for a return to routine monitoring under
§ 141.625(c). You must conduct
increased monitoring under § 141.625 at
the monitoring locations in the
monitoring plan developed under
§ 141.622 beginning at the date
identified in § 141.620(c) for compliance
with this subpart and remain on
increased monitoring until you qualify
for a return to routine monitoring under
§141.625(c).
§141.629 [Reserved]
§141.630 Reporting and recordkeeping
requirements.
(a) Reporting. (1) You must report the
following information for each
monitoring location to the State within
10 days of the end of any quarter in
which monitoring is required:
(i) Number of samples taken during
the last quarter.
(ii) Date and results of each sample
taken during the last quarter.
(iii) Arithmetic average of quarterly
results for the last four quarters
(LRAAs).
(iv) Whether the MCL was violated.
. (2) If you are a subpart H system
seeking to qualify for or remain on
reduced TTHM/HAA5 monitoring, you
must report the following source water
TOG information for each treatment
plant that treats surface water or ground
water under the direct influence of
surface water to the State within 10 days
of the end of any quarter in which
monitoring is required:
(i) The number of source water TOG
samples taken each month during last
quarter.
(ii) The date and result of each sample
taken during last quarter.
(iii) The quarterly average of monthly
samples taken during last quarter.
(iv) The running annual average
(RAA) of quarterly averages from the
past four quarters.
(v) Whether the RAA exceeded 4.0
mg/L.
(b) Recordkeeping. You must retain
any subpart V monitoring plans and
your subpart V monitoring results as
required by §141.33.
PART 142— NATIONAL PRIMARY
DRINKING WATER REGULATIONS
IMPLEMENTATION
1. The authority citation for part 142
continues to read as follows:
Authority: 42 U.S.C. 300f, 300g-l, 300g-2,
300g-3, 300g-4, 300g-5, 300g-6,300J-4,
300J-9, and300j-ll.
2. Section 142,14 is amended by
adding paragraph (a)(8) to read as
follows:
§ 142.14 Records kept by States.
(a) * * *
(8) Any decisions made pursuant to
the provisions of 40 CFR part 141,
subparts U and V of this chapter.
(i) Those systems for which the State
has determined that the 40 CFR part
141, subpart L approved monitoring site
is representative of the highest TTHM
and HAA5 and therefore have been
granted a very small system waiver
under § 141.603(c) of this chapter. The
State must provide a copy of the
decision to the system. A copy of the
decision must be kept until reversed or
revised.
(ii) System IDSE reports, plus any
modifications required by the State.
Reports must be kept until reversed or
revised in their entirety.
* * * * *
3. Section 142.16 is amended by
adding paragraph (m) to read as follows:
§ 142.16 Special primacy conditions.
* * * * *
(m) Requirements for States to adopt
40 CFR part 141, subparts U and V. In
addition to the general primacy
requirements elsewhere in this part,
including the requirements that State
regulations he at least as stringent as
federal requirements, an application for
approval of a State program revision
that adopts 40 CFR part 141, subparts U
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Federal Register/Vol. 68, No. 159/Monday, August 18, 2003/Proposed Rules
49681
nd V, must contain a description of
ow the State will accomplish the
ollowing:
(1) For PWSs serving fewer than 500
eople, a very small system waiver
rocedure for subpart U IDSE
equirements that will apply to all
ystems that serve fewer than 500
eople without the State making a
ystem-by-system waiver determination,
the State elects to use such an
uthority.
(2) A procedure for evaluating system-
pecific studies under § 141.603(a) of
lis chapter, if system-specific studies
re conducted in the State.
(3) A procedure for determining that
multiple consecutive system entry
points from a single wholesale system to
a single consecutive system should be
treated as a single treatment plant for
monitoring purposes.
[4) A procedure for addressing
consecutive systems outside the
provisions of § 141.29 of this chapter or
part 141 subparts U and V of this
chapter, if the State elects to use such
an authority.
(5) A procedure for systems to
identify significant excursions.
PART 143—NATIONAL SECONDARY
DRINKING WATER REGULATIONS
1. The authority citation for part 143
continues to read as follows:
Authority: 42 U.S.C. 300f et seq.
2. In § 143.4, the table in paragraph fb)
is amended by revising entries 2 and 9
and footnotes 3 and 4, and by adding
footnote 6 to read as follows:
§ 143.4 Monitoring.
*****
(b)* * *
Contaminant
EPA
ASTM-
SM4 18th and 19th ed.
SM4 20th ed.
Other
Chloride
300.0'
300.1*
D4327-97
4110 B 4110 B.
D512-89B
4500-CI-D 4500-CI-D
450O-CI-B 4500-CI-B
Sulfate
300.0' D4327-97 .... 4110B 4110B.
300.16
375.2' 4500-SO42-F
4500-SO42-C, D 4500-SO42-C, D.
D516-90 4500-SO42-E 4500-SO42-E.
1 "Methods for the Determination of Inorganic Substances in Environmental Samples", EPA/600/R-93-100, August 1993. Available at NTIS,
B94-120821.
* * • * *
3 Annual Book ofASTM Standards, 1994, 1996, or 1999, Vols. 11.01 and 11.02, ASTM International; any year containing the cited version of
e method may be used. Copies may be obtained from ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428.
4Standard Methods for the Examination of Water and Wastewater, 18th edition (1992), 19th edition (1995), or 20th edition (1998). American
ublic Health Association, 1015 Fifteenth Street, NW, Washington, DC 20005. The cited methods published in any of these three editions may
used, except that the versions of 3111 B, 3111 D, and 3113 B in the 20th edition may not be used.
» * • * *
6 "Methods for the Determination of Organic and Inorganic Compounds in Drinking Water", Vol. 1, EPA 815-R-00-014, August 2000. Available
NTIS, PB2000-106981.
TC Doc. 03-18149 Filed 8-15-03; 8:45 ami
ILUNG CODE 656Q-50-P
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