v>EPA
United States Office of Water EPA 815-B-06-002
Environmental (4601) January 2006
Protection
Agency
INITIAL DISTRIBUTION SYSTEM
EVALUATION GUIDANCE MANUAL
FOR THE FINAL STAGE 2 DISINFECTANTS
AND DISINFECTION BYPRODUCTS RULE
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Note on the Initial Distribution System Evaluation Guidance Manual for
the Final Stage 2 Disinfectants and Disinfection Byproducts Rule
Purpose:
The purpose of this guidance manual is solely to provide technical information for water
systems and states to assist them in complying with the Initial Distribution System Evaluation
(IDSE), a component of the Stage 2 Disinfectants and Disinfection Byproducts Rule (Stage 2
DBPR). This guidance is not a substitute for applicable legal requirements, nor is it a regulation
itself. Thus, it does not impose legally-binding requirements on any party, including EPA,
states, or the regulated community. Interested parties are free to raise questions and objections
to the guidance and the appropriateness of using it in a particular situation. Although this
manual describes many methods for complying with IDSE requirements, the guidance presented
here may not be appropriate for all situations, and alternative approaches may provide
satisfactory performance. The mention of trade names or commercial products does not
constitute endorsement or recommendation for use.
Authorship:
This manual was developed under the direction of EPA's Office of Water, and was
prepared by The Cadmus Group, Inc. and Malcolm Pirnie, Inc. Questions concerning this
document should be addressed to:
Elin Warn Betanzo and Thomas Grubbs
U.S. Environmental Protection Agency
Mail Code 4607M
1200 Pennsylvania Avenue NW
Washington, DC 20460-0001
Tel: (202) 564-1807 (Elin Warn Betanzo)
(202) 564-5262 (Thomas Grubbs)
Fax: (202) 564-3767
Email: Betanzo.Elin@epamail.epa.gov and Grubbs.Thomas@epamail.epa.gov
IDSE Guidance Manual for the Final Stage 2 DBPR i January 2006
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Acknowledgments:
American Water Works Association
Association of Metropolitan Water Agencies
Association of State Drinking Water Agencies
Ken Bousfield—Utah Division of Drinking Water
Andrew DeGraca—San Francisco Water
Walter Grayman—W.M. Grayman Consulting
Mike Grimm—Oregon Health Department
Rich Haberman—California Department of Health Services
Mike Hotaling—City of Newport News
Doug Howie—HDR Engineering
Alexa Obolensky—Philadelphia Water Department
David Reckhow—University of Massachusetts, Amherst
Tom Schaeffer—Association of Metropolitan Water Agencies
Charlotte Smith—Charlotte Smith & Associates
Scott Summers—Colorado University
Jeffrey Swertfeger-Cincinnati Water Works
Jim Uber—University of Cincinnati
Marguerite Young—Clean Water Action
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Contents
List of Exhibits vii
List of Examples viii
List of IDSE Forms viii
List of Checklists ix
List of Worksheets ix
List of IDSE Requirements Summary Sheets x
Acronyms xi
Definitions xii
1.0 Introduction 1-1
1.1 Getting Started 1-1
1.1.1 What is the IDSE? What is its purpose? 1-1
1.1.2 Do I have to conduct an IDSE? 1-2
1.1.3 What guidance materials are available for the IDSE? 1-2
1.1.4 How can I get copies of EPA guidance materials? 1-4
1.1.5 How do I use this guidance manual? 1-4
1.1.6 Whom do I call with questions? 1-7
1.2 Overview of IDSE Options 1-7
1.3 IDSE Schedule 1-8
1.4 Early Implementation Process 1-8
1.5 Changes to IDSE Requirements Since the Proposed Stage 2 DBPR 1-10
2.0 Determining Your IDSE Schedule and Option 2-1
2.1 System Characteristics that Affect IDSE Requirements 2-1
2.2 Determining Your IDSE Schedule 2-1
2.3 Determining Your IDSE Option 2-4
2.4 IDSE Requirements Summary Sheets 2-4
3.0 Very Small System Waiver 3-1
3.1 Qualifying for the VSS Waiver 3-1
3.2 Selecting a Stage 2 DBPR Compliance Monitoring Site 3-2
3.3 Next Steps: Preparing the Stage 2 DBPR Compliance Monitoring Plan 3-3
4.0 40/30 Certification 4-1
4.1 Qualification Criteria 4-2
4.2 Preparing and Submitting the Certification Letter 4-4
4.3 Recordkeeping 4-4
4.4 Selecting Stage 2 Compliance Monitoring Sites 4-7
4.4.1 You Have THE SAME Number of Stage 1 Sites as Required by the Stage 2
DBPR 4-8
4.4.2 You Have MORE Stage 1 Sites than Required by the Stage 2 DBPR 4-8
4.4.3 You Have FEWER Stage 1 Sites than Required by the Stage 2 DBPR 4-10
4.5 Next Steps: Preparing the Stage 2 DBPR Compliance Monitoring Plan 4-11
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5.0 System Specific Study Using Existing Monitoring Results 5-1
5.1 Qualifying for an Existing Monitoring Results SSS 5-3
5.1.1 Evaluating Existing Monitoring Data 5-3
5.1.2 Evaluating Treatment and Source Conditions 5-7
5.1.3 Evaluating Distribution System Conditions 5-8
5.1.4 Compiling Your Data and Calculating LRAAs 5-10
5.2 Preparing Your Existing Monitoring Results SSS Plan 5-10
5.3 Selecting Stage 2 DBPR Compliance Monitoring Sites and Preparing the IDSE
Report 5-27
5.3.1 Selecting Stage 2 DBPR Compliance Monitoring Locations 5-28
5.3.2 Determining Your Stage 2 DBPR Compliance Monitoring Dates 5-35
5.3.3 Preparing the IDSE Report 5-35
5.4 Recordkeeping 5-49
5.5 Next Steps: Preparing the Stage 2 DBPR Compliance Monitoring Plan 5-49
6.0 System Specific Study Using a Distribution System Hydraulic Model 6-1
6.1 Minimum Model Requirements and Calibration 6-5
6.1.1 Physical System Data 6-6
6.1.2 Demand Data 6-6
6.1.3 Operational Controls 6-9
6.1.4 Calibration 6-10
6.2 Modeling Analysis 6-13
6.2.1 Water Age Modeling 6-14
6.2.2 Modeling Analysis Example 6-15
6.3 Determining SSS Monitoring Requirements and Schedule 6-18
6.4 Preparing your Modeling Study Plan 6-20
6.5 Selecting SSS Monitoring Sites and Conducting Monitoring 6-33
6.5.1 Select SSS Monitoring Locations 6-40
6.5.1.1 Identify Near Entry Point Monitoring Locations 6-33
6.5.1.2 Use Your Model to Identify Average Residence Time and High TTHM
Locations 6-34
6.5.1.3 Use Your Model and Other Data to Identify High HAAS Sites 6-37
6.5.1.4 Finalize SSS Monitoring Locations 6-38
6.5.2 Special Case: Using DBF Formation Modeling to Select Sites 6-40
6.5.3 Conducting Monitoring 6-40
6.6 Selecting Stage 2 DBPR Compliance Monitoring Sites and Schedule 6-41
6.6.1 Analyzing Model Results at Monitoring Locations 6-42
6.6.2 Analyzing SSS Monitoring Results 6-43
6.6.3 Comparison of Modeling and Sampling Results 6-43
6.6.4 Select Final Compliance Monitoring Sites 6-44
6.6.5 Determining Your Stage 2 DBPR Compliance Monitoring Schedule 6-48
6.7 Preparing the IDSE Report 6-48
6.8 Recordkeeping 6-69
6.9 Next Steps: Preparing the Stage 2 DBPR Compliance Monitoring Plan 6-69
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7.0 Standard Monitoring 7-1
7.1 Selecting Standard Monitoring Sites and Preparing Your Standard Monitoring Plan . 7-2
7.1.1 Recommended Approach for Selecting Standard Monitoring Sites 7-3
Step 1: Gather Data and Tools 7-5
Step 2: Identify Near Entry Point Standard Monitoring Sites 7-7
Step 3: Identify Candidate Average Residence Time Sites 7-9
Step 4: Identify Candidate High TTHM Sites 7-13
Step 5: Identify Candidate High HAAS Standard Monitoring Sites 7-14
Step 6: Plot Sites on a Distribution System Map 7-17
Step 7: Select Standard Monitoring Sites from Candidate Sites 7-17
Step 8: Write Justifications and a Summary of Data 7-19
7.1.2 Selecting Your Peak Historical Month and Determining Standard Monitoring
Schedule 7-21
7.1.3 Preparing Your Standard Monitoring Plan 7-23
7.2 Conducting Standard Monitoring 7-35
7.3 Selecting Stage 2 DBPR Compliance Monitoring Sites and Preparing the IDSE
Report 7-37
7.3.1 Selecting Stage 2 DBPR Compliance Monitoring Locations 7-38
7.3.2 Determining Your Stage 2 DBPR Compliance Monitoring Schedule 7-44
7.3.3 Preparing the IDSE Report for Standard Monitoring 7-44
7.4 Recordkeeping 7-61
7.5 Next Steps: Preparing the Stage 2 DBPR Compliance Monitoring Plan 7-61
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Appendices
Appendix A Factors Affecting DBF Formation
Appendix B Stage 2 DBPR and LT2ESWTR Compliance Schedule
Appendix C TTHM and HAAS Sampling Protocol
Appendix D Consecutive and Wholesale System Issues
Appendix E Example IDSE Existing Monitoring Results System Specific Study Plan and
Report for a Surface Water System Serving 40,000 People
Appendix F Example IDSE System Specific Study Using a Hydraulic Model for a Surface
Water System Serving 57,000 People
Appendix G Complex Modeling Analysis Example for a System with Multiple Sources
Appendix H Example IDSE Standard Monitoring Plan and Report for a Surface Water System
Serving 160,000 People
Appendix I Example IDSE Standard Monitoring Plan and Report for a Ground Water System
Serving 200,000 People
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List of Exhibits
Exhibit 1.1 IDSE Tool Home Page 1-3
Exhibit 1.2a IDSE Guidance Manual Chapters and Appendices 1-5
Exhibit 1.2b Building a Custom IDSE Guidance Manual for Your System 1-6
Exhibit 1.3 Staggered Schedule for the IDSE 1-9
Exhibit 1.4 Options for Submitting IDSE Material to EPA and States Through the IPMCl . 1-10
Exhibit 2.1 IDSE Schedule Number 2-2
Exhibit 2.2 Example Letter from EPA to System on Schedule 1 2-3
Exhibit 2.3 Flowchart for Determining Your IDSE Option 2-5
Exhibit 2.4 List of Requirements Summary Sheets 2-9
Exhibit 3.1 Required Contents of Stage 2 DBPR Compliance Monitoring Plans 3-3
Exhibit 4.1 40/30 Criteria Compliance Dates 4-2
Exhibit 4.2 Stage 2 Compliance Monitoring Requirements 4-7
Exhibit 4.3 Typical Characteristics of High TTHM Sites 4-10
Exhibit 4.4 Required Contents of Stage 2 DBPR Compliance Monitoring Plans 4-12
Exhibit 5.1 Qualifying Period for the Existing Monitoring Results SSS 5-3
Exhibit 5.2 Examples of System Changes 5-9
Exhibit 5.3 Required Elements of Your SSS Plan 5-11
Exhibit 5.4 Required Elements of Your IDSE Report for an Existing Monitoring Results
SSS 5-28
Exhibit 5.5 Protocol for Selecting Stage 2 DBPR (Subpart V) Compliance Monitoring
Sites 5-31
Exhibit 5.6 Required Contents of Stage 2 DBPR Compliance Monitoring Plans 5-50
Exhibit 6.1 Minimum Distribution System Hydraulic Model Requirements 6-2
Exhibit 6.2 Minimum Reporting Requirements for Modeling Study Plan 6-3
Exhibit 6.3a Sample Subdivision Layout in a Less Skeletonized Model 6-8
Exhibit 6.3b Sample Subdivision Layout in a More Skeletonized Model 6-8
Exhibit 6.4 Example Diurnal Demand Variation Pattern 6-10
Exhibit 6.5 Sample of an Acceptable Graph for Demonstration of Model Calibration 6-13
Exhibit 6.6 Schematic of the Case Study Distribution System 6-16
Exhibit 6.7 Water Age Graph for the Tank with the Highest Water Age 6-17
Exhibit 6.8 Locational Average Water Age Throughout the Study Area 6-18
Exhibit 6.9 Requirements for Modeling SSS Sampling 6-19
Exhibit 6.10 Ranking of Water Age Results 6-35
Exhibit 6.11 Histogram of Water Age Results 6-36
Exhibit 6.12 Example of Typical Water Age Variation over Time 6-43
Exhibit 6.13 Protocol for Selecting Stage 2 DBPR (Subpart V) Compliance Monitoring
Sites 6-47
Exhibit 6.14 Minimum Requirements for IDSE Report for a Modeling SSS 6-49
Exhibit 6.15 Required Contents of Stage 2 DBPR Compliance Monitoring Plans 6-70
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Exhibit 7.1 Required Elements of Your Standard Monitoring Plan 7-2
Exhibit 7.2 Recommended Approach to Selecting Standard Monitoring Sites 7-4
Exhibit 7.3 Data and Tools for Selecting Different Types of Standard Monitoring Sites .... 7-6
Exhibit 7.4 Guidelines for Using Disinfectant Residual Data 7-11
Exhibit 7.5 Typical Characteristics of High TTHM Sites 7-13
Exhibit 7.6 Required Elements of Your IDSE Report for Standard Monitoring 7-37
Exhibit 7.7 Protocol for Selecting Stage 2 DBPR (Subpart V) Compliance Monitoring
Sites 7-40
Exhibit 7.8 Required Contents of Stage 2 DBPR Compliance Monitoring Plans 7-62
List of Examples
Example 2.1 Determining IDSE Requirements for a Consecutive System Serving 25,000
People 2-8
Example 4.1 Qualifying for a 40/30 Certification 4-3
Example 4.2 Completed 40/30 Certification Letter Using Form 1 4-6
Example 5.1 Qualifying With Multiple Years of Data Collected From Different Locations . 5-6
Example 5.2 Qualifying Using Data from a One-Year Special Study 5-7
Example 5.3 Selecting Stage 2 DBPR Compliance Monitoring Sites 5-32
Example 5.4 Maintaining a Historical Record 5-34
Example 5.5 Providing Geographic Coverage When Choosing Stage 2 Sites 5-34
Example 7.1 System with Fewer Entry Points than Required Near Entry Point Standard
Monitoring Sites 7-8
Example 7.2 System with More Entry Points than Required Near Entry Point Sample Sites . 7-9
Example 7.3 Average Disinfectant Residual Calculation 7-12
Example 7.4 Selecting Stage 2 DBPR Compliance Monitoring Sites 7-41
Example 7.5 Maintaining a Historical Record 7-43
Example 7.6 Providing Geographic Coverage When Choosing Stage 2 Sites 7-43
List of IDSE Forms
Form 1 40/30 Certification Letter 4-5
Form 2 Existing Monitoring Results SSS Plan 5-19
Form 3 IDSE Report for an Existing Monitoring Results SSS 5-41
Form 4 Modeling Study Plan 6-27
Form 5 IDSE Report for a Modeling SSS 6-57
Form 6 Standard Monitoring Plan 7-29
Form 7 IDSE Report for Standard Monitoring 7-51
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List of Checklists
Checklist 2.1 Minimum Requirements Checklist for an SSS Using a Distribution System
Hydraulic Model 2-6
Checklist 2.2 Minimum Requirements Checklist for an SSS Using Existing Monitoring
Results 2-7
Checklist 5.1 Minimum Requirements Checklist for an SSS Using Existing Monitoring
Results 5-4
List of Worksheets
Worksheet 4.1 Stage 2 DBPR Site Selection for Systems Getting the 40/30 Certification ... 4-9
Worksheet 5.1 Stage 2 DBPR Site Selection Worksheet for an Existing Monitoring Results
SSS 5-30
Worksheet 6.1 Stage 2 DBPR Site Selection Worksheet for a Modeling SSS 6-46
Worksheet 7.1 Selecting the Peak Historical Month 7-22
Worksheet 7.2 Stage 2 DBPR Site Selection Worksheet for Standard Monitoring 7-39
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List of IDSE Requirements Summary Sheets
Requirement Summary Sheet
Requirements for Very Small System Waivers
40/30 Certification Requirements - Schedule 1
40/30 Certification Requirements - Schedule 2
40/30 Certification Requirements - Schedule 3
40/30 Certification Requirements - Schedule 4
System-Specific Study Requirements - Schedule 1
System-Specific Study Requirements - Schedule 2
System-Specific Study Requirements - Schedule 3
System-Specific Study Requirements - Schedule 4
System-Specific Study Requirements - Attachment (For All Schedules)
Standard Monitoring Requirements - Schedule 1
Standard Monitoring Requirements - Schedule 2
Standard Monitoring Requirements - Schedule 3
Standard Monitoring Requirements - Schedule 4
Standard Monitoring Requirements - Attachment (For All Schedules)
Page
2-11
2-13
2-15
2-17
2-19
2-21
2-23
2-25
2-27
2-29
2-31
2-33
2-35
2-37
2-39
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Acronyms
CBI Confidential Business Information
CWS Community water system
DBF Disinfection byproduct
DBPR Disinfectants and Disinfection Byproducts Rule
EPA U.S. Environmental Protection Agency
EPS Extended period simulation
FOIA Freedom of Information Act
GIS Geographic information system
GWUDI Ground water under the direct influence of surface water
HAA Haloacetic acid
HAAS The sum of five HAA species
HPC Heterotrophic plate count
ICR Information Collection Rule
IDSE Initial distribution system evaluation
IPMC Information Processing and Management Center
LRAA Locational running annual average
LT2ESWTR Long Term 2 Enhanced Surface Water Treatment Rule
MCL Maximum contaminant level
M-DBP Microbial and disinfection byproduct
NOM Natural organic matter
NPDWR National Primary Drinking Water Regulation
NTNCWS Nontransient noncommunity water system
PWS Public water system
PWSID Public water system identification number
SDWA Safe Drinking Water Act
SSS System-specific study
STEP Simple Tools for Effective Performance
SUVA Specific ultraviolet absorbance
SWTR Surface Water Treatment Rule
TCR Total Coliform Rule
THM Trihalomethane
TOC Total organic carbon
TNCWS Transient noncommunity water system
TTHM Total trihalomethanes
TTHMFP Total trihalomethane formation potential
UV Ultraviolet light
VSS Very small system
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Definitions
Aquifer: a geological formation composed of rock, gravel, sand, or other porous material that
yields water to wells or springs.
Biodegradation: a biological process where HAASs are broken down into smaller compounds by
microbes.
Booster disinfection: the practice of adding disinfectant in the distribution system to maintain
disinfectant residual concentration throughout the distribution system.
Combined distribution system: the interconnected distribution system consisting of the
distribution systems of wholesale systems and of the consecutive systems that receive finished
water. 40CFR141.2
Community water system: a public water system which serves at least 15 service connections
used by year-round residents or regularly serves at least 25 year-round residents. 40 CFR 141.2
Consecutive system: a public water system that receives some or all of its finished water from
one or more wholesale systems. Delivery may be through a direct connection or through the
distribution system of one or more consecutive systems. 40 CFR 141.2
Disinfectant: any oxidant, including but not limited to chlorine, chlorine dioxide, chloramines,
and ozone added to water in any part of the treatment or distribution process, that is intended to
kill or inactivate pathogenic microorganisms. 40 CFR 141.2
Disinfectant residual concentration: the concentration of disinfectant that is maintained in a
distribution system. Disinfectant could be free chlorine (the sum of the concentrations of
hypochlorous acid (HOC1) and hypochlorite (OC1")) or combined chlorine (chloramines). It is
used in Surface Water Treatment Rule as a measure for determining CT.
Disinfection: a process which inactivates pathogenic organisms in water by chemical oxidants or
equivalent agents. 40 CFR 141.2
Disinfection byproduct (DBF): compound formed from the reaction of a disinfectant with
organic and inorganic compounds in the source or treated water during disinfection and
distribution.
Dual Sample set: a set of two samples collected at the same time and same location, with one
sample analyzed for TTFDVI and the other sample analyzed for HAAS. Dual sample sets are
collected for the purpose of conducting an IDSE under subpart U and determining compliance
with the TTHM and HAAS MCLs under subpart V. 40 CFR 141.2
Entry Point: the point(s) where finished water first enters the distribution system from one or
more sources. Samples taken at these points represent minimum residence time in the
distribution system.
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Finished Water: water that is introduced into the distribution system of a public water system
and is intended for distribution and consumption without further treatment, except as treatment
necessary to maintain water quality in the distribution system (e.g., booster disinfection, addition
of corrosion control chemicals). 40 CFR 141.2
GAC10: granular activated carbon filter beds with an empty-bed contact time of 10 minutes
based on average daily flow and a carbon reactivation frequency of every 180 days, except that
the reactivation frequency for GAC10 used as a best available technology for compliance with
subpart VMCLs under §141.64(b)(2) shall be 120 days. 40 CFR 141.2
GAC20: granular activated carbon filter beds with an empty-bed contact time of 20 minutes
based on average daily flow and a carbon reactivation frequency of every 240 days. 40 CFR
141.2
Ground water system: public water systems that use ground water only or purchase ground water
from other systems (40 CFR 141.2). For the purposes this guidance manual, ground water
systems refers to the subset of systems that disinfect their water, or purchase disinfected ground
water, even if they do not apply any additional treatment.
Ground water under the direct influence of surface water (GWUDI): any water beneath the
surface of the ground with significant occurrence of insects or other macroorganisms, algae, or
large-diameter pathogens such as Giardia lamblia, or Cryptosporidium, or significant and
relative rapid shifts in water characteristics such as turbidity, temperature, conductivity, or pH
which closely correlate to climatological or surface water conditions. Direct influence must be
determined for individual sources in accordance with criteria established by the State. The State
determination of direct influence may be based on site-specific measurements of water quality
and/or documentation of well construction characteristics and geology with field evaluation. 40
CFR 141.2
Haloacetic acid (HAA): one of the family of organic compounds named as a derivative of acetic
acid, wherein one to three hydrogen atoms in the methyl group in acetic acid are each substituted
by a halogen atom (namely, chlorine and bromine) in the molecular structure.
Haloacetic acids (five) (HAAS): the sum of the concentrations in milligrams per liter of the
haloacetic acid compounds (monochloroacetic acid, dichloroacetic acid, trichloroacetic acid,
monobromoacetic acid, and dibromoacetic acid), rounded to two significant figures after
addition. 40 CFR 141.2
Heterotrophicplate count (HPC): a procedure for estimating the number of heterotrophic
bacteria in water, measured as the number of colony forming units per 100 mL.
Information Processing and Management Center (IPMC): a receiving, processing, and mailing
facility with a web-based data management system that allows EPA and states to access, track,
and respond to IDSE submissions.
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Influence zone: the portions of the distribution system supplied with water from a particular
source of supply.
Locational running annual average (LRAA): the average of sample results taken at a particular
monitoring location during the previous four calendar quarters. 40 CFR 141.2
Maximum contaminant level (MCL): the maximum permissible level of a contaminant in water
which is delivered to any user of a public water system. 40 CFR 141.2
Maximum contaminant level goal (MCLG): the maximum level of a contaminant in drinking
water at which no known or anticipated adverse effect on the health of persons would occur, and
which allows an adequate margin of safety. Maximum contaminant level goals are
nonenforceable health goals. 40 CFR 141.2
Mixing Zone: an area in the distribution system where water flowing from two or more different
sources blend.
Monitoring site: the location where samples are collected.
Non-community water system: a public water system that is not a community water system. A
non-community water system is either a "transient non-community water system (TNCWS)" or a
"non-transient non-community water system (NTNCWS) 40 CFR 141.2
Non-transient non-community water system (NTNCWS): a public water system that is not a
community water system and that regularly serves at least 25 of the same persons over 6 months
per year. 40 CFR 141.2
Population served: the retail number of people served by a water system. Systems typically
work with their State to determine population served for compliance purposes. Note that IDSE
and Stage 2 compliance monitoring requirements (e.g., number of samples and sampling
frequency) are based on the population served by the water system. IDSE and Stage 2
compliance monitoring schedules, however, are based on the largest population served by
systems in the combined distribution system. If you do not know the population of your system,
ask your state.
Public water system (PWS): a system for the provision to the public of water for human
consumption through pipes or, after August 5, 1998, other constructed conveyances, if such
system has at least fifteen service connections or regularly serves an average of at least twenty-
five individuals daily at least 60 days out of the year. Such term includes: any collection,
treatment, storage, and distribution facilities under control of the operator of such system and
used primarily in connection with such system; and any collection or pretreatment storage
facilities not under such control which are used primarily in connection with such system. Such
term does not include any "special irrigation district." A public water system is either a
"community water system" or a "noncommunity water system. 40 CFR 141.2
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Residence time: the time period lasting from when the water is treated to a particular point in the
distribution system. Also referred to as water age.
Residual disinfection: also referred to as "secondary disinfection." The process whereby a
disinfectant (typically Chlorine or Chloramines) is added to finished water in order to maintain a
disinfection residual in the distribution system.
State: the agency of the State or Tribal government which has jurisdiction over public water
systems. During any period when a State or Tribal government does not have primary
enforcement responsibility pursuant to Section 1413 of the Safe Drinking Water Act, the term
"State" means the Regional Administrator, U.S. Environmental Protection Agency. 40 CFR
141.2
Subpart H systems: public water systems using surface water or ground water under the direct
influence of surface water as a source that are subject to the requirements of 40 CFR 141.2 (H).
40 CFR 141.2
Surface water: all water which is open to the atmosphere and subject to surface runoff. 40 CFR
141.2
Total chlorine residual: the sum of combined chlorine (chloramine) and free available chlorine
residual.
Total trihalomethanes (TTHM): the sum of the concentration in milligrams per liter of the
trihalomethane compounds (trichloromethane [chloroform], dibromochloromethane,
bromodichloromethane, and tribromomethane [bromoform]), rounded to two significant figures.
40 CFR 141.2
Tracer study: a procedure for estimating hydraulic properties of the distribution system, such as
residence time. Where more than one water source feeds the distribution system, tracer studies
can be used to determine the zone of influence of each source.
Transient Non-Community Water System (TNCWS): a non-community water system that does
not regularly serve at least 25 of the same persons over six months per year. 40 CFR 141.2
Trihalomethane (TFDVI): one of the family of organic compounds named as derivatives of
methane, wherein three of the four hydrogen atoms in methane are each substituted by a halogen
atom in the molecular structure. 40 CFR 141.2
Water distribution system model: a computer program that can simulate the hydraulic, and in
some cases, water quality behavior of water in a distribution system.
Wholesale system: a public water system that treats source water as necessary to produce
finished water and then delivers some or all of that finished water to another public water
system. Delivery may be through a direct connection or through the distribution system of one
or more consecutive systems. 40 CFR 141.2
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1.0 Introduction
This chapter covers:
1.1 Getting Started (Read this Section First)
1.2 Overview of ID SE Options
1.3 IDSE Schedule
1.4 Early Implementation Process
1.5 Changes to IDSE Requirements Since the Proposed Stage 2 DBPR
The Administrator of the EPA signed the Stage 2 Disinfectants and Disinfection
Byproducts Rule (DBPR) on December 15, 2005, and it was published in the Federal Register on
January 4, 2006 (71 FR 388). This rule applies to all community and non-transient
noncommunity water systems that provide disinfected water (other than water disinfected only
by Ultraviolet [UV] light) to their customers. The rule has two primary sections. Subpart U is
referred to as the Initial Distribution System Evaluation (IDSE) section. The requirements of
this part of the rule are discussed in this manual. Subpart V, the Stage 2 Disinfection Byproducts
Requirements, is referred to as Stage 2 Compliance Monitoring in this guidance manual. Stage 2
Compliance Monitoring Requirements are an extension of the Stage 1 DBPR. Note that systems
that are exempt from the IDSE portion of the rule may not be exempt from the Stage 2
Compliance Monitoring section.
EPA developed this Initial Distribution System Evaluation Guidance Manual to help
systems meet the IDSE requirements of the Stage 2 DBPR. System personnel should start by
reading Section 1.1 to answer basic questions about the IDSE, select the appropriate guidance
materials to meet IDSE requirements, and get instructions on how to use this manual.
1.1 Getting Started
Read this Section First
1.1.1 What is the IDSE? What is its purpose?
IDSEs are an important part of the Stage 2 DBPR. They are one-time studies conducted
by water systems to identify distribution system locations with high concentrations of
trihalomethanes (THMs) and haloacetic acids (HAAs). Water systems will use results from the
IDSE, in conjunction with their Stage 1 DBPR compliance monitoring data, to select compliance
monitoring locations for the Stage 2 DBPR.
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1.1.2 Do I have to conduct an IDSE?
You are subject to the IDSE requirements of the Stage 2 DBPR if you meet the following
criteria:
• You use a primary or residual disinfectant other than ultraviolet light (UV), or you
are a consecutive system that delivers water that has been treated with a primary or
residual disinfectant other than UV.
AND
• You are a community water system (CWS) of any size, or you are a non-transient
non-community water system (NTNCWS) that serves > 10,000 people.
IDSE requirements do not apply to NTNCWSs serving fewer than 10,000 people, although these
systems have other requirements under the Stage 2 DBPR. Transient non-community water
systems (TNCWSs) are not subject to any part of the Stage 2 DBPR.
There are four options systems can use to comply with the IDSE requirements of the
Stage 2 DBPR:
• Qualify for a Very Small System (VSS) Waiver
• Meet 40/30 Certification requirements
Conduct a System Specific Study (SSS) using existing monitoring results or a
distribution system hydraulic model
• Conduct Standard Monitoring
The four options are described briefly in Section 1.2 of this chapter, with further details provided
in the remainder of this guidance manual.
1.1.3 What guidance materials are available for the IDSE?
EPA has developed two guidance manuals and an on-line tool to help you comply with
the IDSE requirement. This manual is comprehensive and includes IDSE requirements and
technical guidance for all system sizes and types and all IDSE options, designed for easy access
to specific modules. The second manual, entitled the Initial Distribution System Evaluation
Guide for Systems Serving < 10,000 People, is targeted to smaller systems and focuses on
information they are most likely to use. It provides examples to help smaller systems as they
proceed with satisfying IDSE requirements. It does not, however, discuss the IDSE SSS options.
EPA has also developed the IDSE Tool, available on-line at
http://www.epa.gov/safewater/disinfection/stage2 and on CD. The IDSE tool walks systems
through the entire IDSE process, and it can be used in place of the IDSE guidance manuals. It
contains a Wizard you can use to determine your requirements and select the best IDSE option
for your system. The tool then creates Custom Forms for your system size and type that can be
submitted electronically for EPA or state review. See Section 1.4 for more information. Exhibit
1.1 shows the IDSE Tool home page.
IDSE Guidance Manual for the Final Stage 2 DBPR 1-2 January 2006
-------
Exhibit 1.1 IDSE Tool Home Page
Welcome to the IDSE Tool!
(IBSfij TaBl isjafisipplfcation idssignejj IB
1 . If IDSE: RefuirerrteFitssapply
'ThelDSE'Tool jpEcwfdes aecess ta;a':wizard1b.
hftlp'ipu 'defBrmfii'g Mfliiirsmertis as well as
at? eKiff ^poffiBri to 'assist in efeatiftf and
If you prefer to work offline, you can download
a desktop version of the IDSE Tool. However,
the desktop version has limited functionality
(i.e. general information about your system
will not be automatically filled in, you cannot
submit completed plans and/or reports
online). To download the desktop version,
click here.
Help
@) Print
Instructions:
The IDSE Tool provides you with the ability to determine what, if any, IDSE Requirements apply to your Public
Water System. If you already know which IDSE option is best for your system, select the Plan/Report Entry
button below. If you are not sure what your requirements are or which IDSE option is best for you, then select
the Begin Wizard button.
You should have your schedule information letter sent by EPA or their State with you while going through the
IDSE Wizard as some questions refer to the letter. Systems that EPA or the State anticipate are on schedules
1 or 2 should receive a letter in January 2006. Systems that EPA or the State anticipate are on schedules 3 or
4 should receive a letter in July 2006. If you did not receive a letter, you can still use the IDSE Tool. However, if
you buy or sell water (i.e. you are part of a combined distribution system), you will need to call EPA or your
state to determine your compliance schedule for the IDSE. To identify your point of contact, click here.
NOTE: You will not be able to go back to a previous question once you have answered a question. If you feel
that you have answered a question incorrectly or if you would like to work through the wizard more than once,
click the Home button to begin the wizard again.
Go To Plan/Report Entry
(I know what my requirements are)
If you know which plan and / or report you would like
to fill out, select the button below to go directly to
the Plan/Report Entry portion of the IDSE Tool. You
will be taken to the CDX login page. If you have an
existing CDX account, please login. If you are a new
user, select "register with CDX" to create a
username and password. This login ensures the
information you submit is secure, and also allows
you to save your work so you don't have to complete
your entire plan or report all at once.
Plan/Report_Entry_', i
Go To Wizard
(I am not sure what my requirements are)
The wizard will help you determine if the IDSE
requirements apply to your system and if so, what
you have to do to meet the requirements. The wizard
will ask you a series of questions. Based on your
response the wizard will determine the nest question
as well as which requirements apply to you. Once
completed, the wizard will provide you with a results
screen that will display your schedule and the best
IDSE option for your system based on your
responses. You will also be able to continue to the
Plan/Report Entry portion from the results screen.
Click the button below to begin.
Begin Wizard '
The IDSE Guidance Manual, the IDSE Guide for Systems Serving < 10,000 People, and
the IDSE Tool address only IDSE requirements and DO NOT cover other provisions of the Stage
2 DBPR. For additional guidance on implementing the Stage 2 DBPR, you can refer to the
following EPA materials:
• The Stage 2 DBPR Quick Reference Guide
• Stage 2 Disinfectant and Disinfection Byproducts Rule: Small Entity Compliance Guide
One of the Simple Tools for Effective Performance (STEP) Guide Series (draft version)
EPA will be releasing draft versions of additional Stage 2 DBPR guidance manuals soon,
including The Consecutive Systems Guidance Manual, The Simultaneous Compliance Guidance
Manual, and The Operational Evaluation Guidance Manual. Your state may have additional,
state-specific materials to assist you in complying with the Stage 2 DBPR.
IDSE Guidance Manual for the Final Stage 2 DBPR 1-3
January 2006
-------
1.1.4 How can I get copies of EPA guidance materials?
• You can download guidance manuals and fact sheets from EPA's Web site at
http://www.epa.gov/safewater/disinfection/stage2.
• You can call the Safe Drinking Water Hotline at 1 -800-426-4791
• You can call the National Service Center for Environmental Publications at 1-800-
490-9198 or visit their Web site at http://www.epa.gov/ncepihom.
Also, you may wish to contact your state drinking water program office for additional guidance.
1.1.5 How do I use this guidance manual?
To help you find information quickly, EPA has designed this manual in a modular
format. While Chapters 1 and 2 contain information for all systems, Chapters 3, 4, 5, 6 and 7
each contain comprehensive requirements for a specific IDSE option. Appendices are organized
similarly. The first three appendices include general information for all systems. Appendix D
addresses consecutive and wholesale system issues. Appendices E through H provide examples
for specific IDSE options. Exhibit 1.2 shows which chapters and appendices you should use for
the different IDSE options.
EPA recommends that once you have read the introductory materials in Chapter 1, you
use the flowchart in Chapter 2 to determine the best IDSE option for your system. Then you
can go to the chapter and appendices addressing your IDSE option and skip the rest of the
manual. If you are accessing this guidance manual electronically, you can download only those
chapters and appendices that you need to build a custom manual for your system.
Remember that the IDSE Tool does these steps for you. The IDSE Tool ,/\
Wizard asks questions about your system and, based on your answers, extracts
the appropriate requirements summary sheet and guidance manual material. IDSE Tool
Chapter 2 contains requirements summary sheets for each IDSE option and compliance
schedule. These sheets contain compliance deadlines for IDSE submissions and other important
information. EPA recommends that you make a copy of your requirements summary sheets (or
if you are accessing the manual electronically, print them out) and keep them handy throughout
the IDSE process.
IDSE Guidance Manual for the Final Stage 2 DBPR 1-4 January 2006
-------
Exhibit 1.2a IDSE Guidance Manual Chapters and Appendices
Chapters
1 Introduction
2 Determining Your IDSE Schedule and Option
3* Very Small System Waiver
4* 40/30 Certification
5* System Specific Study Using Existing Monitoring Results
6* System Specific Study Using a Distribution System Hydraulic Model
7* Standard Monitoring
Appendices
A Factors Affecting DBF Formation
B Stage 2 DBPR and LT2ESWTR Compliance Schedule
C TTHM and HAAS Sampling Protocol
D Consecutive and Wholesale System Issues
E Example System Specific Study using Existing Monitoring Results for a Surface Water
System Serving 40,000 People
F Example System Specific Study Using a Hydraulic Model for a Surface Water System
Serving 55,000 People
G Complex Modeling Analysis Example for a System with Multiple Sources
H Example IDSE Standard Monitoring Plan and Report for a Surface Water System
Serving 160,000 People
I Example IDSE Standard Monitoring Plan and Report for a Ground Water System
Serving 200,000 People
* You need one of these Chapters for the IDSE
IDSE Guidance Manual for the Final Stage 2 DBPR 1-5 January 2006
-------
Exhibit 1.2b Building a Custom IDSE Guidance Manual for Your System
All Systems
PLUS
Chapter 1
Chapter 2
Appendix A
Appendix B
Systems qualifying for the VSS Waiver
Chapter 3
Systems qualifying for 40/30 Certification
Chapter 4
Systems conducting an SSS using existing
monitoring results
Systems conducting an SSS using a model
Chapter 5
Appendix E
Chapters
Appendix C
Appendix F
Appendix G
Systems conducting standard monitoring
Chapter 7
Appendix C
Appendix H
Appendix I
PLUS
Consecutive and wholesale systems only
Appendix D
IDSE Guidance Manual for the Final Stage 2 DBPR 1-6
January 2006
-------
1.1.6 Whom do I call with questions?
Because compliance activities begin soon after the Stage 2 DBPR is
finalized, EPA and states will be working together to implement the IDSE. In
some cases, EPA will be your main point of contact during the first phases of the
IDSE. In other cases, your state will be your main point of contact.
To identify your point of contact for the IDSE, visit EPA's website at
http://www.epa.gov/safewater/disinfection/stage2. The website contains a list of contact
numbers for the IDSE by state. You can also call the EPA SDWA hotline at 1-800-426-4791 for
this information. Refer to Section 1.4 of this chapter for more information on how the IDSE will
be implemented.
1.2 Overview of IDSE Options
There are four options available to systems to meet IDSE requirements. Your option will
depend on your technical resources, existing monitoring results, size, and preference. The four
options are described briefly below, with further details provided in the remainder of this
guidance manual.
• Very Small System (VSS) Waiver. Systems serving fewer than 500 people that
have TTHM and HAAS data automatically receive the VSS waiver unless they are
notified by EPA or their state that they must conduct an IDSE. Systems receiving the
VSS waiver have no further IDSE requirements.
• 40/30 Certification. Systems can fulfill the IDSE requirements by certifying that all
individual TTHM and HAAS monitoring results for compliance with the Stage 1
DBPR are less than or equal to 0.040 mg/L for TTHM and 0.030 mg/L for HAAS
during a prescribed 2-year time period. In addition, the system must not have had any
Stage 1 DBPR monitoring violations for TTHM and HAAS during the same period.
The system must submit the required 40/30 certification and, unless told otherwise by
EPA or their state, they have no further requirements under the IDSE.
• System Specific Study (SSS). Systems can meet IDSE requirements using existing
monitoring results or a distribution system hydraulic model if their data or model
meet certain minimum criteria. Systems conducting an SSS must prepare an SSS
plan and IDSE report. Existing monitoring requirements were developed to be
equivalent to standard monitoring.
• Standard Monitoring. Any system can choose to conduct standard monitoring, even
if they receive a VSS, qualify for the 40/30 certification, or have enough data to
conduct an SSS. Standard monitoring entails 1 year of distribution system
monitoring at multiple locations (in addition to Stage 1 DBPR monitoring). The
required sampling frequency and minimum number of sample locations depend on
IDSE Guidance Manual for the Final Stage 2 DBPR 1-7 January 2006
-------
population served and source water type. Systems conducting standard monitoring
must prepare a standard monitoring plan and IDSE report.
1.3 IDSE Schedule
IDSE activities begin soon after the Stage 2 DBPR is finalized. Appendix B provides the
overall schedule for the Stage 2 DBPR and Long Term 2 Enhanced Surface Water Treatment
Rule (LT2ESWTR) to show how the IDSE fits into the overall compliance schedule for both
rules. Exhibit 1.3 shows a more detailed schedule for IDSE activities only. Note that the
schedule is staggered by system size, and that the schedule for consecutive and wholesale
systems is based on the population served by the largest system in the combined distribution
system. Guidance for determining your schedule is in Chapter 2.
1.4 Early Implementation Process
Because IDSE activities begin soon after the Stage 2 DBPR is finalized, EPA and states
will be working together to implement the IDSE. To facilitate review and processing of IDSE
submissions, EPA has created the Information Processing and Management Center (IPMC).
The IPMC is both a receiving facility and a web-based data management system that allows EPA
and states to access, track, and respond to IDSE submissions.
The IPMC is password protected and accessible only by EPA and state drinking water
representatives. IDSE submissions will not, however, be considered confidential business
information (CBI) and are subject to the Freedom of Information Act (FOIA). Therefore, your
IDSE submissions should not contain information that poses a security risk to your system.
Chapters 5, 6, and 7 of this manual provide guidelines on the kinds of information you may want
to exclude from your distribution system schematic for security reasons.
One advantage of the IPMC is that it provides a one-stop location for IDSE submissions.
Regardless of whether EPA or your state is reviewing your IDSE materials, all submissions go to
the same address. See Exhibit 1.4 on page 1-10 for ways in which you can submit IDSE
materials to the IPMC. EPA and/or your state will review your IDSE plan and report. If they
have concerns regarding your submission, they will work with you to resolve those issues during
the one year review period.
If you have questions during the IDSE, you should visit EPA's website at
http://www.epa.gov/safewater/disinfection/stage2 to determine the contact name and phone
number for the IDSE for your state. You can also call the Safe Drinking Water Hotline at 1-800-
426-4791 for this information.
IDSE Guidance Manual for the Final Stage 2 DBPR 1-8 January 2006
-------
Exhibit 1.3 Staggered Schedule for the IDSE
Schedule 1
Systems
serving
>1 00,000 1
Schedule 2
Systems
serving
50,000-99,999 1
Schedule 3
Systems
serving
10,000-49,999 1
Schedule 4
Systems
serving
<1 0,000 1
1 Forconsecutiveand
2Communicationwith
2006
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2007
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2008
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2009
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reviews plans2 (Recommended) reviews reports
IDSE plans an
certificationsc
IL
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JFMA|M|J JA|SOND
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lue
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reviews plans2
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due
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reviews plans2 .(Recommended) reviews reports
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JF|M|A|IV j J|ASO|ND
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and
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wholesalesystems, theschedule is based onthe populationserved bythe largestsystem ina combineddistribution system.
thesystem is included intheEPA/statereview period.
IDSE Guidance Manual for the Final Stage 2 DBPR
1-9
January 2006
-------
Exhibit 1.4 Options for Submitting IDSE Material to EPA and States Through the
IPMC1
Option 1
Option 2
Option 3
Use the IDSE Tool
to submit completed
certifications, plans
and reports
electronically
Mail paper copies of
submissions to:
STAGE 2 DBPR
US EPA-IPMC
P O Box 98
Dayton, OH 45401-0098
E-mail electronic submissions
as attachments to:
stage2mdbp@epa.gov
Notes:
1. You can use one of these three options to submit IDSE materials to the IPMC.
The IPMC accepts a variety of electronic formats:
• Adobe PDF file (*.pdf)
• Microsoft Word (*.doc)
• WordPerfect (*.wpd)
• Image files (*.gif, *.bmp, *.jpg, *jpeg)
• Microsoft Excel (*.xls)
• Text file (*.txt)
1.5 Changes to IDSE Requirements Since the Proposed Stage 2 DBPR
Several changes have been made to the IDSE requirements since the publication of the
proposed Stage 2 DBPR on August 18, 2003. Many of these changes are in response to public
comment received on the proposed rule and are intended to facilitate implementation. These
changes, which are discussed in more detail below, include:
• Change from plant-based to population-based monitoring for all systems
• Change in definition of consecutive systems
• Staggered IDSE schedule
Changes to VSS waivers
• Change in 40/30 requirements
• Clarification to the IDSE SSS option
• Elimination of Stage 2A
Change from plant-based to population-based monitoring for all systems
The Stage 2 DBPR proposal included population-based monitoring requirements for
consecutive systems that purchase all of their water. For all other systems, plant-based
IDSE Guidance Manual for the Final Stage 2 DBPR 1-10
January 2006
-------
monitoring requirements were proposed. The plant-based approach, consistent with Stage 1
DBPR compliance monitoring requirements, is grounded in the assumption that larger systems
have more treatment plants and thus greater system complexity. While this is generally true, the
plant-based approach created disproportionately burdensome monitoring requirements for some
systems where the number of plants did not correlate with system size, such as larger systems
with only a few very large plants or smaller systems with many disinfecting wells. Moreover, a
plant-based approach can complicate monitoring of purchased water systems, particularly
complex ones with multiple connections.
For these reasons, EPA has developed population-based compliance monitoring
requirements for all systems for the final Stage 2 DBPR. EPA believes that the new
population-based approach makes monitoring requirements simpler and more equitable for
systems of the same size and type.
Change in definition of consecutive system
For the Stage 2 DBPR proposal, the definition for consecutive systems specified the
minimum length of time (60 days) a system must receive water from a wholesale system to be
considered a consecutive system. EPA received public comments on this definition. Several
commenters expressed concerns with including a time period of water delivery that defined
whether a system was a consecutive system or wholesale system. This change was also made
due to the change to population based monitoring because it is no longer necessary to define
consecutive system entry points as it was under plant based monitoring. EPA has dropped this
requirement from the final rule and has provided some flexibility for states to determine which
systems are part of a combined distribution system (without presenting a time criterion).
Staggered IDSE schedule
EPA has modified the proposed compliance schedule to stagger deadlines for CWSs and
NTNCWSs serving 10,000 to 99,999 people to allow for a more evenly distributed workload and
greater opportunity for EPA and state involvement. The final compliance schedule includes a
formal review period for EPA and/or state review of IDSE plans and 40/30 certifications as well
as IDSE reports. The staggered schedule also provides time for analytical laboratories to build
up capacity as necessary to accommodate the sample analysis needs of systems. The new IDSE
plan and IDSE report submission dates are shown in Exhibit 1.3. It is important to note that, as
in the proposal, smaller systems may have to comply on an earlier schedule than indicated for
their individual system size if they are part of a combined distribution system that includes a
large system. This is discussed further in Chapter 2.
Changes to VSS waiver?,
The final rule grants a waiver from the IDSE requirements to community water systems
serving fewer than 500 people that have taken TTHM and HAAS samples. This provision was
changed from the proposal to reflect that most small systems have sampling locations that are
representative of both high TTHM and high HAAS because they have small and simple
IDSE Guidance Manual for the Final Stage 2 DBPR 1-11 January 2006
-------
distributions systems. In addition, many very small systems are ground water systems which
typically have stable DBF levels (ground water systems tend to have lower DBF levels than
surface water systems). EPA recognizes, however, that there may be some small systems with
extended or complex distribution systems that should be studied further to determine new
sampling locations. For this reason, EPA or a state can contact a very small system and require
them to conduct an IDSE.
Change in 40/30 requirements
The reporting requirements for the 40/30 certification option have been reduced from the
requirements in the proposed Stage 2 DBPR. In the proposal, systems qualifying for the 40/30
certification were required to submit all qualifying data and provide recommendations for Stage
2 compliance monitoring locations. The final rule requires systems to submit a certification that
their data meets all the requirements of the 40/30 certification and to include their Stage 2
compliance monitoring recommendations in their Stage 2 compliance monitoring plan. These
changes were made to reduce the reporting burden on systems that qualify for the 40/30
certification and to maintain consistency with monitoring plan requirements under the Stage 1
DBPR. This approach also gives systems more time to select appropriate monitoring sites for
Stage 2 compliance monitoring. EPA or the state may request systems to submit the data, a
distribution system schematic, and/or recommendations for Stage 2 compliance monitoring as
part of the 40/30 certification.
Clarification to the IDSE SSS option
The final rule includes more specific requirements than the proposal regarding how
systems can use distribution system hydraulic models and existing monitoring results for the
IDSE SSS. This change was made to help systems better understand expectations under this
provision and lessen the chances of an SSS plan not being approved. The new modeling
requirements reflect that distribution system hydraulic models can appropriately identify
monitoring locations by predicting water age in distribution systems if they meet certain
minimum requirements. Existing monitoring results requirements are equivalent to Standard
Monitoring requirements, except they apply to data already collected.
Elimination of Stage 2A
The Stage 2 DBPR proposal included a phased-in approach to calculating compliance
with MCLs using a Locational Running Annual Average (LRAA), referred to as Stage 2A and
Stage 2B which coincided with the IDSE period. EPA received public comments that found this
confusing, and this provision is no longer in the final rule. What was referred to in the proposal
as Stage 2B compliance monitoring is now referred to as Stage 2 Compliance Monitoring.
IDSE Guidance Manual for the Final Stage 2 DBPR 1-12 January 2006
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2.0 Determining Your IDSE Schedule and Option
This chapter covers:
2.1 System Characteristics that Affect IDSE Requirements
2.2 Determining Your IDSE Schedule
2.3 Determining Your IDSE Option
2.4 IDSE Requirements Summary Sheets
2.1 System Characteristics that Affect IDSE Requirements
Your IDSE schedule, option, and other requirements depend on your system
characteristics. In general, there are three system characteristics that drive IDSE requirements:
• Whether you are a subpart H system or a ground water system.
• The population served by your system.
• If you are a consecutive or wholesale system, the population served by the largest
system in your combined distribution system.
Regulatory definitions for subpart H systems, consecutive systems, wholesale systems, and
combined distribution systems are provided in the definitions section at the beginning of this
guidance manual. Appendix D provides additional discussion of important definitions for
consecutive and wholesale systems.
2.2 Determining Your IDSE Schedule
EPA has established four IDSE compliance schedules, shown graphically in Exhibit 1.3
and summarized in the table in Exhibit 2.1. If you are a consecutive or wholesale system, your
schedule is based on the population served by the largest system in your combined distribution
system. If you are not a consecutive or wholesale system, your schedule is based on the
population served by your individual system. EPA and your state have worked together to
identify which systems are part of combined distribution systems.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-1 January 2006
-------
Exhibit 2.1 IDSE Schedule Number
If you are this kind of system:
Systems serving 100,000 or more people OR belonging to
a combined distribution system in which the largest system
serves 100,000 people or more
Systems serving 50,000 to 99,999 people OR belonging to
a combined distribution system in which the largest system
serves 50,000 to 99,999 people
Systems serving 10,000 to 49,999 OR belonging to a
combined distribution system in which the largest system
serves 10,000 to 49,999 people
Systems serving fewer than 10,000 people and not
belonging to a combined distribution system in which any
system serves 10,000 people or more
You are on
IDSE
schedule
number
1
2
3
4
Your first
deadline is
October 1, 2006
April 1, 2007
October 1, 2007
April 1, 2008
Every system that is subject to the Stage 2 DBPR should receive a letter from EPA or the
state with information on the Stage 2 DBPR and a determination of IDSE schedule (i.e., schedule
1, 2, 3, or 4). Exhibit 2.2 is an example of a letter sent by EPA to a system on schedule 1.
Letters from states and letters to systems on other schedules look similar. Systems that EPA or
the state anticipates are on schedules 1 and 2 should receive a letter in February 2006. Systems
that EPA or the state anticipates are on schedules 3 and 4 should receive a letter in July 2006.
States determined your schedule based on their records on your population served and
connections to other systems. You should make sure the schedule determination in the letter is
consistent with your system size, source water type, and buying / selling relationships with other
systems before proceeding.
Some systems may be planning treatment changes before, during, or after the IDSE.
Most treatment plant modifications should not impact the relative formation of DBFs in your
distribution system. There are no provisions in the Stage 2 DBPR that allow the IDSE schedule
to be changed or delayed1. Not meeting the IDSE compliance deadlines in your requirements
summary sheets results in a Tier 3 monitoring and reporting violation for your system.
1 The Stage 2 DBPR contains provisions that allow systems to modify their Stage 2 DBPR compliance
monitoring plan after their IDSE has been completed. Systems should work with their state if they believe that their
Stage 2 compliance monitoring sites should be changed after their IDSE is completed.
IDSE Guidance Manual for the Final Stage 2 DBPR
January 2006
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Exhibit 2.2 Example Letter from EPA to System on Schedule 1
System Name January 31, 2006
System Address
City State Zip
*** Important New Rule Roll Out ***
Stage 2 Disinfectants and Disinfection Byproduct Rule (Stage 2 DBPR)
This letter applies to those systems serving 100,000 or more people OR those systems in which the largest
system in their combined distribution system serves 100,000 or more people. These systems may also be
referred to as Schedule 1 systems.
This letter is the third in a series of communications to inform you of the Stage 2 DBPR requirements. The Rule
was published in the Federal Register on January 4, 2006. The Stage 2 DBPR builds on existing regulations by
requiring water systems to meet disinfection byproduct maximum contaminant levels (MCLs) at each disinfection
byproduct monitoring site in the distribution system to better protect public health. All community water
systems (CWSs) and non-transient noncommunity water systems (NTNCWSs) that use or deliver water treated with
a primary or residual disinfectant other than ultraviolet light are subject to the Stage 2 DBPR requirements.
However, NTNCWS, serving less than 10.000 people do not have to comply with the Initial Distribution System
Evaluation (IDSE) requirements (see below for an explanation of IDSE). An electronic copy of the Stage 2 DBPR
can be downloaded from EPA's website at www.epa.gov/safewater/disinfection/stage2.
The first major requirement of the Stage 2 DBPR is for systems to conduct an IDSE. The purpose of the IDSE is to
identify locations in the distribution system that have the highest trihalomethane (TTHM) and highest haloacetic
acid (HAAS) concentrations. The locations in the distribution system with the highest TTHM and highest HAAS
concentrations will be used as Stage 2 DBPR compliance monitoring sites.
EPA and State records show that your system is required to comply with Schedule 1 IDSE
requirements. These requirements are based on the information that your system:
• Serves 100,000 or more people (or those systems those systems in which the largest system in your
combined distribution system serves 100,000 or more people); and
• Provides water that has been treated with a primary or residual disinfectant other than ultraviolet
light.
If you believe our records are incorrect please notify us at stage2mdbp(£jepa.gov as soon as possible.
By October 1, 2006, Schedule 1 systems will have to comply with IDSE requirements by submitting a
standard monitoring plan, system specific study plan, or a 40/30 certification. Systems that qualify for
a very small system waiver would be exempt from this IDSE requirement.
(Continued)
IDSE Guidance Manual for the Final Stage 2 DBPR 2-3 January 2006
-------
Whom should I call if I don't receive my letter?
To identify your point of contact for the IDSE, visit EPA's website at
http://www.epa.gov/safewater/disinfection/stage2. The website contains a list of contact
numbers for the IDSE by state. You can also call the EPA SDWA hotline at 1-800-426-
4791 for this information.
2.3 Determining Your IDSE Option
There are four options available to meet the requirements of the IDSE:
• Qualify for a Very Small System (VSS) Waiver
• Meet 40/30 Certification requirements
• Conduct a System Specific Study (SSS) using existing monitoring results or a hydraulic
model
• Conduct Standard Monitoring
You can use the flowchart in Exhibit 2.3 and Checklists 2.1 and 2.2 to help you determine the right
IDSE option for your system. Example 2.1 shows how a surface water system serving 25,000
people used the information in this chapter to determine their requirements.
The IDSE Tool works through the flowchart and checklists to determine the most
suitable IDSE Option for your system. The tool is available on EPA's website at
http://www.epa.gov/safewater/disinfection/stage2.
2.4 IDSE Requirements Summary Sheets
EPA has prepared Requirements Summary Sheets that contain key information and
compliance deadlines for each IDSE schedule and option. A list of requirements summary sheets
and their page numbers is provided in Exhibit 2.4 and in the table of contents of this guidance
manual. EPA recommends that you make a copy of the requirements summary sheet for your
IDSE schedule and option and keep it handy throughout the IDSE process. If you are conducting
an SSS or standard monitoring, make sure you also make a copy of the Attachment with
monitoring requirements.
How does population served affect my IDSE requirements?
IDSE Schedule
• If you are a consecutive or wholesale system, your IDSE schedule is based on the population
served by the largest system in your combined distribution system and is designated in a letter
from EPA or your state.
• If you are not a consecutive or wholesale system, your IDSE schedule is based on the
population served by your system.
IDSE Monitoring
• For all systems, IDSE monitoring locations and sampling frequency are based on the
population served by your individual system.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-4 January 2006
-------
Exhibit 2.3 Flowchart for Determining Your IDSE Option
Does your
system serve 500
people or
more?
Do you
have TTHM and
HAAS data equivalent
to what is required by
the Stage 1
DBPR?
Do you
have TTHM and HAAS
> required
Yes
No
j"*1^
f You qualify for a very small systemwaiver.
/ You do not have to do an IDSE unless EPA or
(your State contacts you. Go to Page 2-11 for a summary of
V your Stage 2 requirements. See Chapter 3 for more
>> information.
For the periods listed below1, is
Every TTHM sample <. 0.040 mg/L and
Every HAAS sample <. 0.030 mg/L?
If you are on Schedules 1 or 2 -8 consecutive
quarters starting no earlier than January 2004
If you are on Schedules 3 or 4 -8 consecutive
quarters starting no earlier than January 2005
Do you
have a distribution
requirements listed in
Checklist 2.1 on
the next
page?
Does
your data
meet all of
the requirements in
Checklist 2.2
on Page
2-7?
Do you
haveextensive
TTHM and HAAS data
(compliance and/or
operational)?
Haveyou
had any Stage 1 TTH
or HAAS monitoring
violations during the
ligibility period?
You qualify for 40/30 certification.
Go to the follow ing pages:
-Systems on Schedule 1 - Page 2-13
-Systems on Schedule 2 - Page 2-15
-Systems on Schedule 3 - Page 2-17
-Systems on Schedule 4 - Page 2-19
See Chapter 4 for more information on
the 40/30 certification.
No
You are eligible for a system specific
study although you also have the option to
conduct standard monitoring. If you
plan to conduct a system specific study
the follow ing pages:
-Systems on Schedule 1 - Page 2-21
-Systems on Schedule 2 - Page 2-23
-Systems on Schedule 3 - Page 2-25
-Systems on Schedule 4 - Page 2-27
See Chapters 5 and 6 for more information
on system specific studies.
You are required to conduct standard
monitoring. Go to the following pages
-Systems on Schedule 1 - Page 2-31
-Systems on Schedule 2 - Page 2-33
-Systems on Schedule 3 - Page 2-35
-Systems on Schedule 4 - Page 2-37
See Chapter 7 for more information on
standard monitoring.
1Unless you are on reduced monitoring for Stage 1 and were not required to monitor during the specified period. If you did not
monitor during the specified period, you must base your eligibility on compliance samples taken during the 12 months preceding the
specified period.
IDSE Guidance Manual for the Final Stage 2 DBPR
2-5
January 2006
-------
Checklist 2.1 Minimum Requirements Checklist for an SSS
Using a Distribution System Hydraulic Model
Yes No
D D Does your model run in extended period simulation?
D D Does it simulate 24-hr variation in demand and show a consistently repeating 24-hr pattern
of 24-hr residence time?
D D Does your model include 75% of pipe volume?
D D Does it include 50% of pipe length?
D D Does it represent all pressure zones?
D D Does your model include all 12" diameter and larger pipes?
D D Does your model include all 8" diameter and larger pipes that connect pressure zones,
influence zones from different sources, storage facilities, major demand areas, pumps, and
control valves or are known or expected to be significant conveyors of water?
D D Does it include all 6" diameter and larger pipes that connect remote areas of the
distribution system to the main portion of the system?
D D Are all storage facilities with standard operations represented in your model?
D D Are all active pump stations with controls represented in your model?
D D Does your model include all active control valves?
D D Has your model been calibrated (or do you have plans to complete calibration in the next
12 months) for the current configuration of the distribution system during periods of high
TTHM formation potential?
D D Were all storage facilities evaluated as part of the calibration process?
If you answered yes to all of the above questions, you meet EPA's minimum requirements for a model
SSS. Remember, though, that EPA or the state can still require you to conduct standard monitoring,
even if you meet the minimum requirements, or you can choose to conduct standard monitoring.
Refer to Section 6.1 for additional guidance on minimum requirements.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-6 January 2006
-------
Checklist 2.2 Minimum Requirements Checklist for an SSS
Using Existing Monitoring Results
Yes No
D D Do you have at least the minimum number of distribution system monitoring locations
shown in the table below from which you collected TTHM and HAAS samples?
D D Do you have at least the minimum number of TTHM samples and HAAS samples shown in
the table below?
D D Was each monitoring location sampled once during the month of high TTHM, high HAAS or
warmest water temperature for every 12 months of data?
D D Were all samples collected and analyzed in accordance with an approved EPA method
and by a certified laboratory?
D D Were all sample results collected no earlier than five years prior to your SSS plan
submission deadline?
D D Have your distribution system and treatment not changed significantly since you collected
your samples?
D D Are your existing monitoring locations representative of your entire distribution system?
If you answered yes to all of the above questions, you meet EPA's minimum requirements for an SSS using
existing monitoring results. Remember, though, that EPA or your state can still require you to conduct standard
monitoring, even if you meet the minimum requirements, or you can choose to conduct standard monitoring.
Refer to Section 5.1 for additional guidance on minimum requirements.
Source Water
Type
Subpart H
Ground Water
System Size Category
(Population Served)
<500
500-3,300
3,301-9,999
10,000-49,999
50,000-249,999
250,000-999,999
1,000,000-4,999,999
>5,000,000
<500
500-9,999
10,000-99,999
100,000-499,999
>500,000
Minimum Number of
Monitoring Locations
3
3
6
12
24
36
48
60
3
3
12
18
24
Minimum Number of
Samples
TTHM
3
9
36
72
144
216
288
360
3
9
48
72
96
HAAS
3
9
36
72
144
216
288
360
3
9
48
72
96
IDSE Guidance Manual for the Final Stage 2 DBPR
2-7
January 2006
-------
Example 2.1 Determining IDSE Requirements for a Consecutive System Serving
25,000 people
System X is a consecutive system serving 25,000 people. They purchase all of their water from
System Y, which is a wholesale surface water system that serves their own retail population of
110,000 people. System X received a letter from their state notifying them of the new Stage 2
DBPR and stating that they are on Schedule 1. System X called System Y right away to
confirm that they were on the same schedule.
Next, System X began working through the flowchart in Exhibit 2.3 of the IDSE guidance
manual to determine their IDSE option.
They serve more than 500 people and cannot qualify for the VSS waiver.
• Their Stage 1 DBPR monitoring results for TTHM were between 45 and 70
micrograms per liter (i-ig/L), so they did not qualify for the 40/30 certification.
• System X knows that System Y had been collecting TTHM and HAAS samples
from both systems for a long time. They contacted System Y and requested
TTHM and HAAS data collected from System X for the last five years. System
X worked closely with System Y and determined that their existing monitoring
results met the minimum requirements in Checklist 2.2. Therefore, System X
selected the SSS using existing monitoring results as their IDSE option.
To determine which chapters of the IDSE manual they needed, System X referred to Exhibit
1.2. System X then downloaded Chapters 1, 2, and 5, and Appendices A, B, D, and E of the
IDSE guidance manual from http://www.epa.gov/safewater/disinfection/stage2 to build their
own custom manual. They made a copy of the requirements summary sheet titled "System
Specific Study Requirements - Schedule 1" and the "System Specific Study Requirements -
Attachment (For All Schedules)" sheet to keep handy throughout the IDSE process. Then they
began preparing their SSS Plan.
Note: If System Xhad used the IDSE tool, it would have done these steps for /\
them and created a custom form for their SSS Plan. (
IDSE Tool
IDSE Guidance Manual for the Final Stage 2 DBPR 2-8 January 2006
-------
Exhibit 2.4 List of Requirements Summary Sheets
Requirement Summary Sheet
Requirements for Very Small System Waivers
40/30 Certification Requirements - Schedule 1
40/30 Certification Requirements - Schedule 2
40/30 Certification Requirements - Schedule 3
40/30 Certification Requirements - Schedule 4
System Specific Study Requirements - Schedule 1
System Specific Study Requirements - Schedule 2
System Specific Study Requirements - Schedule 3
System Specific Study Requirements - Schedule 4
System Specific Study Requirements - Attachment (For All Schedules)
Standard Monitoring Requirements - Schedule 1
Standard Monitoring Requirements - Schedule 2
Standard Monitoring Requirements - Schedule 3
Standard Monitoring Requirements - Schedule 4
Standard Monitoring Requirements - Attachment (For All Schedules)
Page
2-11
2-13
2-15
2-17
2-19
2-21
2-23
2-25
2-27
2-29
2-31
2-33
2-35
2-37
2-39
IDSE Guidance Manual for the Final Stage 2 DBPR 2-9
January 2006
-------
This page left intentionally blank.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-10 January 2006
-------
Requirements for Very Small System Waivers page i of 2
This summary sheet is for systems that:
• Serve fewer than 500 people, and
• Have taken TTHM and HAAS samples.
WHAT TO DO NOW:
You have NO further requirements for the IDSE unless EPA or your state contacts you. If EPA
or your state contacts you, they will work with you to determine an appropriate IDSE schedule
for your system. See Chapter 3 for more information.
Continue compliance monitoring for the Stage 1 DBPR until you begin compliance monitoring
for the Stage 2 DBPR.
NEXT STEPS:
You must start taking Stage 2 DBPR compliance monitoring samples by the deadline listed on
the next page. You must prepare a Stage 2 compliance monitoring plan before you take your
first compliance sample.
If you have high levels of DBFs, you may need to make system changes to meet the
requirements of the Stage 2 DBPR. See Chapter 1, Section 1.1 of this guidance manual, for a
list of additional guidance materials for the Stage 2 DBPR. If you buy water from another public
water system, see EPA's Consecutive System Guidance Manual for more information.
Reminder:
Your requirements for Stage 2 DBPR compliance monitoring (locations and frequency) are
based on the population served by your system and are listed on the next page.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-11 January 2006
-------
Requirements for Very Small System Waivers
Page 2 of 2
Stage 2 DBPR Compliance Monitoring Deadlines
Schedule (population served)1
Schedule 1 (> 100,000)
Schedule 2 (50,000 - 99,999)
Schedule 3 (10,000 - 49,999)
Schedule 4 (< 10,000)
Year in Which You Must Begin Stage 2
Compliance Monitoring
2012
2012
2013
2013or20142
1 If you are a consecutive or wholesale system, your schedule is based on the largest system in your
combined distribution system. You should have received a letter from EPA or your state with your
schedule for the Stage 2 DBPR.
2 2014 if Cryptosporidium monitoring is required under 141.701 (a)(4) or (a)(6).
Stage 2 DBPR Compliance Monitoring Requirements
Source Water
Type
Subpart H
Ground Water
Population Size
Category1
<500
<500
Monitoring
Frequency2
per year
per year
Distribution System
Monitoring Location3
2
2
1 Your monitoring requirements (location and frequency) are based on the population served by your
individual system.
2 You must monitor during the month of highest DBP concentrations.
3 You are required to take individual TTHM and HAAS samples at the locations with the highest TTHM and
HAAS concentrations, respectively. Only one location with a dual sample set per monitoring period is
needed if the highest TTHM and HAAS concentrations occur at the same location and month.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-12
January 2006
-------
40/30 Certification Requirements - Schedule 1 page iof2
Submit 40/30
Certification by
Oct. 1,2006
Jan. '
>2004 Collect 40/30 Data for Any 8 Consecutive
Quarter Eligibility Period
2004
2005
^
T
2006
Rule Promulgation
This summary sheet is for systems that satisfy all of the following requirements for any 8
consecutive quarter eligibility period beginning no earlier than January 2004:
• You serve 100,000 people or more OR are part of a combined distribution system where
the largest system serves 100,000 people or more
• You have TTHM and HAAS data equivalent to what is required by the Stage 1 DBPR
• No individual sample exceeds 0.040 mg/L for TTHM
• No individual sample exceeds 0.030 mg/L for HAAS
• Your system did not have any TTHM or HAAS monitoring violations
WHAT TO DO NOW:
1. Prepare a certification letter | Due: October 1,2006 |
You must submit the certification letter to the address or e-mail provided below, or use the IDSE
Tool to prepare and submit your certification letter. Note that EPA or your state could contact
you and require more information, or require you to conduct an IDSE.
For more information and letter templates:
See Chapter 4 of this guidance manual. If you are a consecutive or wholesale
system, see Appendix D of this guidance manual. A template you can use for your
40/30 certification letter is included on Page 4-5. If you would like an electronic
template, use the IDSE Tool, available at
http://www.epa.gov/safewater/disinfection/stage2. IDSE To°l
2. Mail your 40/30 certification letter to:
STAGE 2 DBPR
US EPA-IPMC
P O Box 98
Dayton, OH 45401-0098
Email to stage2mdbp@epa.gov or submit electronically via the IDSE tool
3. Continue compliance monitoring for the Stage 1 DBPR until you begin compliance
monitoring for the Stage 2 DBPR.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-13 January 2006
-------
40/30 Certification Requirements - Schedule 1
Page 2 of 2
NEXT STEPS:
You have additional Stage 2 DBPR requirements. You must:
Select Stage 2 DBPR compliance monitoring sites.
• Develop a Stage 2 compliance monitoring plan before you take your first compliance
sample. If you are a subpart H system and you serve more than 3,300 people, you need
to submit your plan to the state.
• Begin annual or quarterly Stage 2 compliance monitoring during the period starting with
April 2012, according to your Stage 2 compliance monitoring plan
See Chapter 1, Section 1.1 of this guidance manual for a list of additional guidance materials
for the Stage 2 DBPR.
Reminder:
Your requirements for Stage 2 compliance monitoring are based on the population of your
system and are listed below
Stage 2 DBPR Compliance Monitoring Requirements
Source
Water
Type
Subpart H
Ground
Water
Population Size
Category1
<500
500-3,300
3,301-9,999
10,000-49,999
50,000-249,999
250,000-999,999
1,000,000-4,999,999
> 5,000,000
<500
500-9,999
10,000-99,999
100,000-499,999
> 500,000
Monitoring
Frequency2
per year
per quarter
per quarter
per quarter
per quarter
per quarter
per quarter
per quarter
per year
per year
per quarter
per quarter
per quarter
Distribution System Monitoring Location
Total per
monitoring
period3
2
2
2
4
8
12
16
20
2
2
4
6
8
Highest
TTHM
Locations
1
1
1
2
3
5
6
8
1
1
2
3
o
J
Highest
HAA5
Locations
1
1
1
1
o
5
4
6
7
1
1
1
2
3
Existing Stage
1DBPR
Compliance
Locations
1
2
3
4
5
1
1
2
1 Your monitoring requirements (location and frequency) are based on the population served by your system.
2 All systems must monitor during month of highest DBP concentrations.
3 Systems on quarterly monitoring must take dual sample sets every 90 days at each monitoring location, except for
subpart H systems serving 500-3,300. Systems on annual monitoring and subpart H systems serving 500-3,300 are
required to take individual TTHM and HAAS samples (instead of a dual sample set) at the locations with the highest
TTHM and HAAS concentrations, respectively. Only one location with a dual sample set per monitoring period is
needed if highest TTHM and HAAS concentrations occur at the same location (and month, if monitored annually).
IDSE Guidance Manual for the Final Stage 2 DBPR 2-14
January 2006
-------
40/30 Certification Requirements - Schedule 2 page i of 2
Submit 40/30
Certification by
April 1,2007
Jan. 1,2004 Collect 40/30 Data for Any 8 Consecutive
Quarter EligibilityPeriod
2004 2005
2006 2007
RulePromulgation
This summary sheet is for systems that satisfy all of the following requirements for any 8
consecutive quarter eligibility period beginning no earlier than January 2004:
• You serve 50,000-99,999 people OR are part of a combined distribution system where
the largest system serves 50,000-99,999 people
• You have TTHM and HAAS data equivalent to what is required by the Stage 1 DBPR
• No individual sample exceeds 0.040 mg/L for TTHM
• No individual sample exceeds 0.030 mg/L for HAAS
• Your system did not have any TTHM or HAAS monitoring violations
WHAT TO DO NOW:
1. Prepare a certification letter | Due: April 1, 2007 |
You must submit the certification letter to the address or e-mail provided below, or use the IDSE
Tool to prepare and submit your certification letter. Note that EPA or your state could contact
you and require more information, or require you to conduct an IDSE.
For more information and letter templates:
See Chapter 4 of this guidance manual. If you are a consecutive or wholesale system, see
Appendix D of this guidance manual. A template you can use for your 40/30
certification letter is included on Page 4-5. If you would like an electronic template, /\
use the IDSE Tool, available at http://www.epa.gov/safewater/disinfection/stage2. (
\
2. Mail your 40/30 certification letter to:
STAGE 2 DBPR
US EPA-IPMC
P O Box 98
Dayton, OH 45401-0098
Email to stage2mdbp@epa.gov or submit electronically via the IDSE tool
3. Continue compliance monitoring for the Stage 1 DBPR until you begin compliance
monitoring for the Stage 2 DBPR.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-15 January 2006
-------
40/30 Certification Requirements - Schedule 2
Page 2 of 2
NEXT STEPS:
You have additional Stage 2 DBPR requirements. You must:
• Select Stage 2 compliance monitoring sites.
• Develop a Stage 2 compliance monitoring plan before you take your first compliance
sample. If you are a subpart H system and you serve more than 3,300 people, you need
to submit your plan to the state.
• Begin annual or quarterly Stage 2 compliance monitoring during the period starting with
October 2012, according to your Stage 2 compliance monitoring plan.
See Chapter 1, Section 1.1 of this guidance manual for a list of additional guidance materials
for the Stage 2 DBPR.
Reminder:
Your requirements for Stage 2 compliance monitoring are based on the population of your
system and are listed below.
Stage 2 DBPR Compliance Monitoring Requirements
Source
Water
Type
Subpart
H
Ground
Water
Population Size
Category1
<500
500-3,300
3,301-9,999
10,000-49,999
50,000-249,999
250,000-999,999
1,000,000-4,999,999
> 5,000,000
<500
500-9,999
10,000-99,999
100,000-499,999
> 500,000
Monitoring
Frequency2
per year
per quarter
per quarter
per quarter
per quarter
per quarter
per quarter
per quarter
per year
per year
per quarter
per quarter
per quarter
Distribution System Monitoring Location
Total per
monitoring
period3
2
2
2
4
8
12
16
20
2
2
4
6
8
Highest
TTHM
Locations
1
1
1
2
3
5
6
8
1
1
2
3
o
J
Highest
HAA5
Locations
1
1
1
1
o
J
4
6
7
1
1
1
2
3
Existing Stage
1DBPR
Compliance
Locations
1
2
3
4
5
1
1
2
1 Your monitoring requirements (location and frequency) are based on the population served by your system.
2 All systems must monitor during month of highest DBP concentrations.
3 Systems on quarterly monitoring must take dual sample sets every 90 days at each monitoring location, except for
subpart H systems serving 500-3,300. Systems on annual monitoring and subpart H systems serving 500-3,300 are
required to take individual TTHM and HAAS samples (instead of a dual sample set) at the locations with the highest
TTHM and HAAS concentrations, respectively. Only one location with a dual sample set per monitoring period is
needed if highest TTHM and HAAS concentrations occur at the same location (and month, if monitored annually).
IDSE Guidance Manual for the Final Stage 2 DBPR 2-16
January 2006
-------
40/30 Certification Requirements - Schedule 3 page i of 2
Submit 40/30
Certification by
Oct. 1,2007
Jan. 1,2005 Collect 40/30 Data for Any 8 Consecutive
Quarter EligibilityPeriod
2005
2006 2007
Rule Promulgation
This summary sheet is for systems that satisfy all of the following requirements for any 8
consecutive quarter eligibility period beginning no earlier than January 2005:
• You serve 10,000-49,999 people OR are part of a combined distribution system where the
largest system serves 10,000-49,999 people
• You have TTHM and HAAS data equivalent to what is required by the Stage 1 DBPR
• No individual sample exceeds 0.040 mg/L for TTHM
• No individual sample exceeds 0.030 mg/L for HAAS
• Your system did not have any TTHM or HAAS monitoring violations
WHAT TO DO NOW:
1. Prepare a certification letter | Due: October 1,2007 |
You must submit the certification letter to the address or e-mail provided below, or use the IDSE
Tool to prepare and submit your certification letter. Note that EPA or your state could contact
you and require more information, or require you to conduct an IDSE.
For more information and letter templates:
See Chapter 4 of this guidance manual. If you are a consecutive or wholesale
system, see Appendix D of this guidance manual. A template you can use for your
40/30 certification letter is included on Page 4-5. If you would like an electronic
template, use the IDSE Tool, available at
http://www.epa.gov/safewater/disinfection/stage2. IDSE Tool
2. Mail your 40/30 certification letter to:
STAGE 2 DBPR
US EPA-IPMC
P O Box 98
Dayton, OH 45401-0098
Email to stage2mdbp@epa.gov or submit electronically via the IDSE tool
3. Continue compliance monitoring for the Stage 1 DBPR until you begin compliance
monitoring for the Stage 2 DBPR.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-17 January 2006
-------
40/30 Certification Requirements - Schedule 3
Page 2 of 2
NEXT STEPS:
You have additional Stage 2 DBPR requirements. You must:
• Select Stage 2 compliance monitoring sites.
• Develop a Stage 2 compliance monitoring plan before you take your first compliance
sample. If you are a subpart H system and you serve more than 3,300 people, you need to
submit your plan to the state.
• Begin annual or quarterly Stage 2 compliance monitoring during the period starting with
October 2013, according to your Stage 2 compliance monitoring plan
See Chapter 1, Section 1.1 of this guidance manual for a list of additional guidance materials for
the Stage 2 DBPR.
Reminder:
Your requirements for Stage 2 compliance monitoring are based on the population of your system
and are listed below
Stage 2 DBPR Compliance Monitoring Requirements
Source
Water Type
Subpart
H
Ground
Water
Population Size
Category1
<500
500-3,300
3,301-9,999
10,000-49,999
50,000-249,999
250,000-999,999
1,000,000-4,999,999
> 5,000,000
<500
500-9,999
10,000-99,999
100,000-499,999
> 500,000
Monitoring
Frequency2
per year
per quarter
per quarter
per quarter
per quarter
per quarter
per quarter
per quarter
per year
per year
per quarter
per quarter
per quarter
Distribution System Monitoring Location
Total per
monitoring
period3
2
2
2
4
8
12
16
20
2
2
4
6
8
Highest
TTHM
Locations
1
1
1
2
o
J
5
6
8
1
1
2
3
3
Highest
HAAS
Locations
1
1
1
1
o
J
4
6
7
1
1
1
2
o
J
Existing Stage 1
DBPR
Compliance
Locations
1
2
3
4
5
1
1
2
1 Your monitoring requirements (location and frequency) are based on the population served by your system.
2 All systems must monitor during month of highest DBP concentrations.
3 Systems on quarterly monitoring must take dual sample sets every 90 days at each monitoring location, except for
subpart H systems serving 500-3,300. Systems on annual monitoring and subpart H systems serving 500-3,300 are
required to take individual TTHM and HAA5 samples (instead of a dual sample set) at the locations with the highest
TTHM and HAA5 concentrations, respectively. Only one location with a dual sample set per monitoring period is
needed if highest TTHM and HAA5 concentrations occur at the same location (and month, if monitored annually).
IDSE Guidance Manual for the Final Stage 2 DBPR 2-18
January 2006
-------
40/30 Certification Requirements - Schedule 4 page i of2
Submit 40/30
Certification by
April 1,2008
Jan.
1 ,2005 Collect 40/30 Data for Any 8 Consecutive
Quarter EligibilityPeriod
2005
2006
2007
^
r
2008
Rule Promulgation
This summary sheet is for systems that satisfy all of the following requirements for any 8
consecutive quarter eligibility period beginning no earlier than January 2005:
• You serve fewer than 10,000 people OR are part of a combined distribution system where
the largest system serves fewer than 10,000 people
• You have TTHM and HAAS data equivalent to what is required by the Stage 1 DBPR
• No individual sample exceeds 0.040 mg/L for TTHM
• No individual sample exceeds 0.030 mg/L for HAAS
• Your system did not have any TTHM or HAAS monitoring violations
WHAT TO DO NOW:
1. Prepare a certification letter | Due: April 1, 2008
You must submit the certification letter to the address or e-mail provided below, or use the IDSE
Tool to prepare and submit your certification letter. Note that EPA or your state could contact
you and require more information, or require you to conduct an IDSE.
For more information and letter templates:
See Chapter 4 of this guidance manual. If you are a consecutive or wholesale
system, see Appendix D of this guidance manual. A template you can use for your /x
40/30 certification letter is included on Page 4-5. If you would like an electronic (
template, use the IDSE Tool, available at
http://www.epa.gov/safewater/disinfection/stage2. IDSE
2. Mail your 40/30 certification letter to:
STAGE 2 DBPR
US EPA-IPMC
P O Box 98
Dayton, OH 45401-0098
Email to stage2mdbp@epa.gov or submit electronically via the IDSE tool
3. Continue compliance monitoring for the Stage 1 DBPR until you begin compliance
monitoring for the Stage 2 DBPR.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-19 January 2006
-------
40/30 Certification Requirements - Schedule 4
Page 2 of 2
NEXT STEPS:
You have additional Stage 2 DBPR requirements. You must:
• Select Stage 2 compliance monitoring sites.
• Develop a Stage 2 compliance monitoring plan before you take your first compliance
sample. If you are a subpart H system and you serve more than 3,300 people, you need to
submit your plan to the state.
• Begin annual or quarterly Stage 2 compliance monitoring during the period starting with
October 2013 or October 2014, according to your Stage 2 compliance monitoring plan.
See Chapter 1, Section 1.1 of this guidance manual for a list of additional guidance materials for
the Stage 2 DBPR.
Reminder:
Your requirements for Stage 2 compliance monitoring are based on the population of your system
and are listed below.
Stage 2 DBPR Compliance Monitoring Requirements
Source
Water
Type
Subpart
H
Ground
Water
Population Size
Category1
<500
500-3,300
3,301-9,999
10,000-49,999
50,000-249,999
250,000-999,999
1,000,000-4,999,999
> 5,000,000
<500
500-9,999
10,000-99,999
100,000-499,999
> 500,000
Monitoring
Frequency2
per year
per quarter
per quarter
per quarter
per quarter
per quarter
per quarter
per quarter
per year
per year
per quarter
per quarter
per quarter
Distribution System Monitoring Location
Total per
monitoring
period3
2
2
2
4
8
12
16
20
2
2
4
6
8
Highest
TTHM
Locations
1
1
1
2
3
5
6
8
1
1
2
o
J
o
J
Highest
HAA5
Locations
1
1
1
1
3
4
6
7
1
1
1
2
3
Existing Stage 1
DBPR
Compliance
Locations
1
2
3
4
5
1
1
2
1 Your monitoring requirements (location and frequency) are based on the population served by your system.
2 All systems must monitor during month of highest DBP concentrations.
3 Systems on quarterly monitoring must take dual sample sets every 90 days at each monitoring location, except for
subpart H systems serving 500-3,300. Systems on annual monitoring and subpart H systems serving 500-3,300 are
required to take individual TTHM and HAA5 samples (instead of a dual sample set) at the locations with the highest
TTHM and HAA5 concentrations, respectively. Only one location with a dual sample set per monitoring period is
needed if highest TTHM and HAA5 concentrations occur at the same location (and month, if monitored annually).
IDSE Guidance Manual for the Final Stage 2 DBPR 2-20
January 2006
-------
System Specific Study Requirements - Schedule 1 page iof2
Submit System
Specific Study Plan
by Oct. 1,2006
Submit IDSE
Report by
Jan. 1,2009
>
Oct. 1,
r
2007 Sept. 30,
Conduct Any
Additional Monitoring
(recommended)
2008
>
2006 2007 2008
r
2009
Rule Promulgation
This summary sheet is for systems that serve 100,000 people or more OR are part of a combined
distribution system where the largest system serves 100,000 people or more.
WHAT TO DO NOW:
1. Develop a System Specific Study Plan | Due: October 1, 2006
For guidance on how to develop your SSS Plan:
• If you are using existing monitoring results, see Chapter 5. Your minimum
data requirements are also listed on the attachment on Page 2-29.
• If you are using a distribution system hydraulic model, see Chapter 6.
• Chapters 5 and 6 contain plan templates. If you would like an electronic
template, see the IDSE Tool: IDSE Tool
http://www.epa.gov/safewater/disinfection/stage2.
Mail your SSS Plan to:
STAGE 2 DBPR
US EPA-IPMC
P O Box 98
Dayton, OH 45401-0098
Email to stage2mdbp@epa.gov or submit electronically via the IDSE tool
EPA or your state will review your SSS plan and contact you before October 1, 2007 to
either let you know it has been approved or discuss necessary changes. If you do not hear
anything by this deadline, consider your SSS plan approved and proceed with your plans.
2. Conduct Any Additional Monitoring I Oct. 1, 2007 - Sept. 30, 2008
Systems using existing monitoring results may take additional samples during the SSS.
Monitoring should be done according to the approved SSS Plan. Systems using models are
required to complete one period of monitoring.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-21
January 2006
-------
System Specific Study Requirements - Schedule 1 page2of2
WHAT TO DO NOW (cont'd):
3. Select Stage 2 Compliance Monitoring Sites and Develop _
IDSE Report for the SSS | U"e: January
The number of Stage 2 compliance monitoring sites required for your system is listed on the
attachment on Page 2-30. For guidance on how to select your sites and write your IDSE report:
• If you are using existing monitoring data, see Chapter 5, Section 5.3.
• If you are using a distribution system hydraulic model, see Chapter 6, Section 6.6 and
Section 6.7.
EPA or your state will review your IDSE report and contact you before April 1, 2009 to either
let you know your Stage 2 compliance monitoring sites and schedule have been approved or to
discuss necessary changes. If you do not hear anything by this deadline, consider your report
approved and start preparing for Stage 2 compliance monitoring.
4. Continue compliance monitoring for the Stage 1 DBPR until you begin compliance
monitoring for the Stage 2 DBPR.
NEXT STEPS:
You will have additional requirements for Stage 2 compliance. Your system will need to:
• If you have high levels of DBFs, you may need to make system changes before April 1,
2012 to meet the requirements of the Stage 2 DBPR. If you buy water, see the
Consecutive System Guidance Manual for more information.
• Develop a Stage 2 compliance monitoring plan before you take your first compliance
sample. If you are a subpart H system and you serve more than 3,300 people, you need
to submit your plan to the state.
• Begin annual or quarterly Stage 2 compliance monitoring during the period starting with
April 2012, according to your Stage 2 compliance monitoring plan.
Reminder:
Your system's monitoring requirements for both the IDSE and Stage 2 compliance monitoring
are based on the population of your system and are listed the attachment on Pages 2-29 and 2-30.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-22 January 2006
-------
System Specific Study Requirements - Schedule 2 page i of 2
Submit System
Specific Study Plan
by April 1,2007
Submit IDSE
Report by
July 1,2009
>
April 1
r
,2008 March 31,
-^ w
Conduct Any
Additional Monitoring
(recommended)
2009
>
r
2006 2007 2008 2009
Rule Promulgation
This summary sheet is for systems that serve 50,000-99,999 people OR are part of a combined
distribution system where the largest system serves 50,000-99,999 people.
WHAT TO DO NOW:
1. Develop a System Specific Study Plan I Due: April 1, 2007
For guidance on how to develop your SSS Plan:
• If you are using existing monitoring results, see Chapter 5. Your minimum data
requirements are also listed on the attachment on Page 2-29.
• If you are using a distribution system hydraulic model, see Chapter 6.
• Chapters 5 and 6 contain plan templates. If you would like an electronic
template, see the IDSE Tool:
http://www.epa.gov/safewater/disinfection/stage2. IDSE Tool
Mail your SSS Plan to:
STAGE 2 DBPR
US EPA-IPMC
P O Box 98
Dayton, OH 45401-0098
Email to stage2mdbp@epa.gov or submit electronically via the IDSE tool
EPA or your state will review your SSS plan and contact you before April 1, 2008 to either
let you know it has been approved or discuss necessary changes. If you do not hear anything by
this deadline, consider your SSS plan approved and proceed with your plans.
2. Conduct Any Additional Monitoring I Apr. 1, 2008 - March 31, 2009
Systems using existing monitoring results may take additional samples during the SSS.
Monitoring should be done according to the approved SSS Plan. Systems using models are
required to complete one period of monitoring.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-23
January 2006
-------
System Specific Study Requirements - Schedule 2 page2of2
WHAT TO DO NOW (cont'd):
3. Select Stage 2 Compliance Monitoring Sites and Develop _
IDSE Report for the SSS Uue: July
The number of Stage 2 compliance monitoring sites required for your system is listed on the
attachment on Page 2-30. For guidance on how to select your sites and write your IDSE report:
• If you are using existing monitoring data, see Chapter 5, Section 5.3.
• If you are using a distribution system hydraulic model, see Chapter 6, Section 6.6 and
Section 6.7.
EPA or your state will review your IDSE report and contact you before October 1, 2009 to
either let you know your Stage 2 compliance monitoring sites and schedule have been approved
or to discuss necessary changes. If you do not hear anything by this deadline, consider your
report approved and start preparing for Stage 2 compliance.
4. Continue compliance monitoring for the Stage 1 DBPR until you begin compliance
monitoring for the Stage 2 DBPR.
NEXT STEPS:
You will have additional requirements for Stage 2 compliance. Your system will need to:
• If you have high levels of DBFs, you may need to make system changes before October
1, 2012 to meet the Stage 2 MCLs. If you buy water, see the Consecutive System
Guidance Manual for more information.
• Develop a Stage 2 compliance monitoring plan before you take your first compliance
sample. If you are a subpart H system and you serve more than 3,300 people, you need
to submit your plan to the state.
• Begin annual or quarterly Stage 2 compliance monitoring during the period starting with
October 2012, according to your Stage 2 compliance monitoring plan.
Reminder:
Your system's monitoring requirements for both the IDSE and Stage 2 compliance monitoring
are based on the population of your system and are listed the attachment on Pages 2-29 and 2-30.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-24 January 2006
-------
System Specific Study Requirements - Schedule 3 page iof2
Submit System
Specific Study Plan
by Oct. 1,2007
Submit IDSE
Report by
Jan. 1,2010
1
Oct. 1
r
, 2008 Sept. 30,
Conduct Any
Additional Monitoring
(recommended)
2009
^
2006 2007 2008 | 2009
r
2010
Rule Promulgation
This summary sheet is for systems that serve 10,000-49,999 people OR are part of a combined
distribution system where the largest system serves 10,000-49,999 people.
WHAT TO DO NOW:
1. Develop a System Specific Study Plan I Due: October 1, 2007
For guidance on how to develop your SSS Plan:
• If you are using existing monitoring results, see Chapter 5. Your minimum data
requirements are also listed on the attachment on Page 2-29.
• If you are using a distribution system hydraulic model, see Chapter 6. /
Chapters 5 and 6 contain plan templates. If you would like an electronic /
template, see the IDSE Tool:
http://www.epa.gov/safewater/disinfection/stage2. IDSE Tool
Mail your SSS Plan to:
STAGE 2 DBPR
US EPA-IPMC
P O Box 98
Dayton, OH 45401-0098
Email to stage2mdbp@epa.gov or submit electronically via the IDSE tool
EPA or your state will review your SSS plan and contact you before October 1, 2008 to
either let you know it has been approved or discuss necessary changes. If you do not hear
anything by this deadline, consider your SSS plan approved and proceed with your plans.
2. Conduct Any Additional Monitoring | Oct. 1, 2008 - Sept. 30, 2009
Systems using existing monitoring results may take additional samples during the SSS.
Monitoring should be done according to the approved SSS Plan. Systems using models are
required to complete one period of monitoring.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-25
January 2006
-------
System Specific Study Requirements - Schedule 3 page2of2
WHAT TO DO NOW (cont'd):
3. Select Stage 2 Compliance Monitoring Sites and Develop _
IDSE Report for the SSS Uue: January *' 2U1U
The number of Stage 2 compliance monitoring sites required for your system is listed on the
attachment on Page 2-30. For guidance on how to select your sites and write your IDSE report:
• If you are using existing monitoring data, see Chapter 5, Section 5.3.
• If you are using a distribution system hydraulic model, see Chapter 6, Section 6.6 and
Section 6.7.
EPA or your state will review your IDSE report and contact you before October 1, 2010 to
either let you know your Stage 2 compliance monitoring sites and schedule have been approved
or to discuss necessary changes. If you do not hear anything by this deadline, consider your
report approved and start preparing for Stage 2 compliance.
4. Continue compliance monitoring for the Stage 1 DBPR until you begin compliance
monitoring for the Stage 2 DBPR.
NEXT STEPS:
You will have additional requirements for Stage 2 compliance. Your system will need to:
• If you have high levels of DBFs, you may need to make system changes before October
1, 2013 to meet the Stage 2 MCLs. If you buy water, see the Consecutive System
Guidance Manual for more information.
• Develop a Stage 2 compliance monitoring plan before you take your first compliance
sample. If you are a subpart H system and you serve more than 3,300 people, you need
to submit your plan to the state.
• Begin annual or quarterly Stage 2 compliance monitoring during the period starting with
October 2013, according to your Stage 2 compliance monitoring plan.
Reminder:
Your system's monitoring requirements for both the IDSE and Stage 2 compliance monitoring
are based on the population of your system and are listed the attachment on Pages 2-29 and 2-30.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-26 January 2006
-------
System Specific Study Requirements - Schedule 4 page i of 2
Submit System
Specific Study Plan
by April 1,2008
Submit IDSE
Report by
July 1,2010
>
April 1
r
, 2009 March 31 ,
Conduct Any
Additional Monitoring
(recommended)
2010
1
r
r
2006
2007
2008
2009
2010
Rule Promulgation
This summary sheet is for systems that serve fewer than 10,000 people OR are part of a
combined distribution system where the largest system serves fewer than 10,000 people.
WHAT TO DO NOW:
1. Develop a System Specific Study Plan I Due: April 1, 2008
For guidance on how to develop your SSS Plan:
• If you are using existing monitoring results, see Chapter 5. Your minimum data
requirements are also listed on the attachment on Page 2-29.
• If you are using a distribution system hydraulic model, see Chapter 6. /^
• Chapters 5 and 6 contain plan templates. If you would like an electronic (
template, see the IDSE Tool: V
http://www.epa.gov/safewater/disinfection/stage2. IDSE To°l
Mail your SSS Plan to:
STAGE 2 DBPR
US EPA-IPMC
P O Box 98
Dayton, OH 45401-0098
Email to stage2mdbp@epa.gov or submit electronically via the IDSE tool
EPA or your state will review your SSS plan and contact you before April 1, 2009 to either
let you know it has been approved or discuss necessary changes. If you do not hear anything by
this deadline, consider your SSS plan approved and proceed with your plans.
2. Conduct Any Additional Monitoring I Apr. 1, 2009 - March 31, 2010
Systems using existing monitoring results may take additional samples during the SSS.
Monitoring should be done according to the approved SSS Plan. Systems using models are
required to complete one period of monitoring.
IDSE Guidance Manual for the Final Stage 2 DBPR
2-27
January 2006
-------
System Specific Study Requirements - Schedule 4 page2of2
WHAT TO DO NOW:
3. Select Stage 2 Compliance Monitoring Sites and Develop _
IDSE Report for the SSS I Uue; July l. ZU1U
The number of Stage 2 compliance monitoring sites required for your system is listed on the
attachment on Page 2-30. For guidance on how to select your sites and write your IDSE report:
• If you are using existing monitoring data, see Chapter 5, Section 5.3.
• If you are using a distribution system hydraulic model, see Chapter 6, Section 6.6 and
Section 6.7.
EPA or your state will review your IDSE report and contact you before October 1, 2010 to
either let you know your Stage 2 compliance monitoring sites and schedule have been approved
or to discuss necessary changes. If you do not hear anything by this deadline, consider your
report approved and start preparing for Stage 2 compliance.
4. Continue compliance monitoring for the Stage 1 DBPR until you begin compliance
monitoring for the Stage 2 DBPR.
NEXT STEPS:
You will have additional requirements for Stage 2 compliance. Your system will need to:
• If you have high levels of DBFs, you may need to make system changes before October
1, 2013 to meet the Stage 2 MCLs. If you buy water, see the Consecutive System
Guidance Manual for more information.
• Develop a Stage 2 compliance monitoring plan before you take your first compliance
sample. If you are a subpart H system and you serve more than 3,300 people, you need
to submit your plan to the state.
• Begin annual or quarterly Stage 2 compliance monitoring during the period starting with
October 2013 or October 2014, according to your Stage 2 compliance monitoring plan.
Reminder:
Your system's monitoring requirements for both the IDSE and Stage 2 compliance monitoring
are based on the population of your system and are listed the attachment on Pages 2-29 and 2-30.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-28 January 2006
-------
System Specific Study Requirements - Attachment (For All Schedules)
Page Iof2
Minimum Sample Requirements for the SSS using Existing Monitoring Results
Source Water
Type
Subpart H
Ground Water
Population Size
Category l
<500
500-3,300
3,301-9,999
10,000-49,999
50,000-249,999
250,000-999,999
1,000,000-4,999,999
^5,000,000
<500
500-9,999
10,000-99,999
100,000-499,999
>500,000
Number of
Monitoring
Locations
3
3
6
12
24
36
48
60
3
3
12
18
24
Number of TTHM
Samples
3
9
36
72
144
216
288
360
3
9
48
72
96
Number of HAAS
Samples
3
9
36
72
144
216
288
360
3
9
48
72
96
1 Your minimum sample requirements (locations and frequency) are based on the population served by your system.
IDSE Guidance Manual for the Final Stage 2 DBPR
2-29
January 2006
-------
System Specific Study Requirements - Attachment (For All Schedules)
Page 2 of 2
Stage 2 Compliance Monitoring Requirements
Source
Water
Type
Subpart
H
Ground
Water
Population Size
Category1
<500
500-3,300
3,301-9,999
10,000-49,999
50,000-249,999
250,000-999,999
1,000,000-4,999,999
>5,000,000
<500
500-9,999
10,000-99,999
100,000-499,999
>500,000
Monitoring
Frequency2
per year
per quarter
per quarter
per quarter
per quarter
per quarter
per quarter
per quarter
per year
per year
per quarter
per quarter
per quarter
Distribution System Monitoring Location
Total per
monitoring
period 3
2
2
2
4
8
12
16
20
2
2
4
6
8
Highest TTHM
Locations
1
1
1
2
3
5
6
8
1
1
2
3
3
Highest HAAS
Locations
1
1
1
1
O
4
6
7
1
1
1
2
O
Existing Stage 1
DBPR Compliance
Locations
1
2
3
4
5
1
1
2
1 Your monitoring requirements (location and frequency) are based on the population served by your system.
2 All systems must monitor during month of highest DBP concentrations.
3 Systems on quarterly monitoring must take dual sample sets every 90 days at each monitoring location, except for subpart H systems serving
500-3,300. Systems on annual monitoring and subpart H systems serving 500-3,300 are required to take individual TTHM and HAA5 samples
(instead of a dual sample set) at the locations with the highest TTHM and HAA5 concentrations, respectively. Only one location with a dual sample
set per monitoring period is needed if highest TTHM and HAA5 concentrations occur at the same location (and month, if monitored annually).
IDSE Guidance Manual for the Final Stage 2 DBPR
2-30
January 2006
-------
Standard Monitoring Requirements - Schedule 1
Page I of 2
Submit Standard
Monitoring Plan
by Oct. 1,2006
Submit IDSE
Report by
Jan. 1,2009
•^
Oct. 1,
r
2007 Sept. 30
•* -*~
Conduct Standard
Monitoring
(recommended)
, 2008
•>
2006 2007 2008
r
2009
Rule Promulgation
IDSE Tool
This summary sheet is for systems that serve 100,000 people or more OR are part of a combined
distribution system where the largest system serves 100,000 people or more.
WHAT TO DO NOW:
1. Develop Standard Monitoring Plan | Due: October 1, 2006
• See Chapter 7, Section 7.1.3 for guidance on how to develop your IDSE Standard
Monitoring Plan. Your monitoring requirements are also listed on the
attachment on Page 2-39.
• Chapter 7 contains plan templates. If you would like an electronic
template, see the IDSE Tool:
http://www.epa.gov/safewater/disinfection/stage2.
Mail your standard monitoring plan to:
STAGE 2 DBPR
US EPA-IPMC
P O Box 98
Dayton, OH 45401-0098
E-mail to stage2mdbp@ epa.gov or submit electronically via the IDSE tool
EPA or your state will review your standard monitoring plan and contact you before
October 1, 2007 to either let you know it has been approved or discuss necessary changes. If
you do not hear anything by this deadline, consider your plan approved and start monitoring.
2. Conduct Standard Monitoring | Oct. 1, 2007 - Sept. 30, 2008
Monitoring should be done according to your standard monitoring plan.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-31
January 2006
-------
Standard Monitoring Requirements - Schedule 1 page2of2
WHAT TO DO NOW (cont'd):
3. Select Stage 2 Compliance Monitoring Sites and Develop _
IDSE Standard Monitoring Report Uue: January *' 2UUy
See Chapter 7, Section 7.3 for guidance on how to select Stage 2 compliance monitoring
sites and write the IDSE report. The number of Stage 2 compliance monitoring sites
required for your system is listed on the attachment on Page 2-40.
• EPA or your state will review your IDSE report and contact you before April 1,
2009 to either let you know your Stage 2 compliance monitoring sites and schedule have
been approved or to discuss necessary changes. If you do not hear anything by this
deadline, consider your plan approved and start preparing for Stage 2 compliance.
4. Continue compliance monitoring for the Stage 1 DBPR until you begin compliance
monitoring for the Stage 2 DBPR.
NEXT STEPS:
You will have additional requirements for Stage 2 compliance. Your system will need to do the
following:
• If you have high levels of DBFs, you may need to make system changes before April 1,
2012 to meet the Stage 2 MCLs. If you buy water, see the Consecutive System Guidance
Manual for more information.
• Develop a Stage 2 compliance monitoring plan before you take your first compliance
sample. If you are a subpart H system and you serve more than 3,300 people, you need
to submit your plan to the state.
• Begin annual or quarterly Stage 2 compliance monitoring during the period starting with
April 2012, according to your Stage 2 compliance monitoring plan.
Reminder:
Your system's monitoring requirements for both the IDSE and Stage 2 compliance monitoring
are based on the population of your system and are listed in the attachment on Pages 2-39 and 2-
40.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-32 January 2006
-------
Standard Monitoring Requirements - Schedule 2 page i of 2
Submit Standard
Monitoring Plan
by April 1,2007
>
April 1
r
2006 2007
Submit IDSE
Report by
July 1,2009
, 2008 March 31
Conduct Standard
Monitoring
(recommended)
2008
,2009
>
r
2009
Rule Promulgation
This summary sheet is for systems that serve 50,000-99,999 people OR are part of a combined
distribution system where the largest system serves 50,000-99,999 people.
WHAT TO DO NOW:
1. Develop Standard Monitoring Plan | Due: April 1,2007
• See Chapter 7, Section 7.1.3 for guidance on how to develop your IDSE Standard
Monitoring Plan. Your monitoring requirements are also listed on the
attachment on Page 2-3 9. A
• Chapter 7 contains plan templates. If you would like an electronic /
template, see the IDSE Tool: •
http://www.epa.gov/safewater/disinfection/stage2. IDSE Tool
Mail your standard monitoring plan to:
STAGE 2 DBPR
US EPA-IPMC
P O Box 98
Dayton, OH 45401-0098
E-mail to stage2mdbp@ epa.gov or submit electronically via the IDSE tool
EPA or your state will review your standard monitoring plan and contact you before April
1, 2008 to either let you know it has been approved or discuss necessary changes. If you do not
hear anything by this deadline, consider your plan approved and start monitoring.
2. Conduct Standard Monitoring [Apr. 1, 2008 - March 31, 2009|
Monitoring should be done according to your standard monitoring plan.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-33
January 2006
-------
Standard Monitoring Requirements - Schedule 2 page2of2
WHAT TO DO NOW (cont'd):
3. Select Stage 2 Compliance Monitoring Sites and Develop n T i 1 ?nno
IDSE Standard Monitoring Report UC: JU y '
See Chapter 7, Section 7.3 for guidance on how to select Stage 2 compliance monitoring
sites and write the IDSE report. The number of Stage 2 compliance monitoring sites
required for your system is listed on the attachment on Page 2-40.
• EPA or your state will review your IDSE report and contact you before October 1,
2009 to either let you know your Stage 2 compliance monitoring sites and schedule have
been approved or to discuss necessary changes. If you do not hear anything by this
deadline, consider your plan approved and start preparing for Stage 2 compliance.
4. Continue compliance monitoring for the Stage 1 DBPR until you begin compliance
monitoring for the Stage 2 DBPR.
NEXT STEPS:
You will have additional requirements for Stage 2 compliance. Your system will need to do the
following:
• If you have high levels of DBFs, you may need to make system changes before October
1, 2012 to meet the Stage 2 MCLs. If you buy water, see the Consecutive System
Guidance Manual for more information.
• Develop a Stage 2 compliance monitoring plan before you take your first compliance
sample. If you are a subpart H system and you serve more than 3,300 people, you need
to submit your plan to the state.
• Begin annual or quarterly Stage 2 compliance monitoring during the period starting with
October 2012, according to your Stage 2 compliance monitoring plan.
Reminder:
Your system's monitoring requirements for both the IDSE and Stage 2 compliance monitoring
are based on the population of your system and are listed in the attachment on Pages 2-39 and 2-
40.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-34 January 2006
-------
Standard Monitoring Requirements - Schedule 3
Page I of 2
Submit Standard Submit IDSE
Monitoring Plan Report by
by Oct. 1,2007 Jan. 1,2010
>
Oct. 1
r
, 2008 Sept. 30,
Conduct Standard
Monitoring
(recommended)
2009
•>
2006 2007 | 2008 | 2009
r
2010
Rule Promulgation
This summary sheet is for systems that serve 10,000-49,999 people OR are part of a combined
distribution system where the largest system serves 10,000-49,999 people.
WHAT TO DO NOW:
1. Develop Standard Monitoring Plan
Due: October 1, 2007
• See Chapter 7, Section 7. 1 .3 for guidance on how to develop your IDSE Standard
Monitoring Plan. Your monitoring requirements are also listed on the
attachment on Page 2-39.
Chapter 7 contains plan templates. If you would like an electronic ,
template, see the IDSE Tool: (
http://www.epa.gov/safewater/disinfection/stage2. IDSE
Mail your standard monitoring plan to:
STAGE 2 DBPR
US EPA-IPMC
P O Box 98
Dayton, OH 45401-0098
E-mail to stage2mdbp@epa.gov or submit electronically via the IDSE tool
EPA or your state will review your standard monitoring plan and contact you before
October 1, 2008 to either let you know it has been approved or discuss necessary changes. If
you do not hear anything by this deadline, consider your plan approved and start monitoring.
2. Conduct Standard Monitoring | Oct. 1, 2008 - Sept. 30, 2009
Monitoring should be done according to your IDSE Standard Monitoring Plan.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-35
January 2006
-------
Standard Monitoring Requirements - Schedule 3 page2of2
WHAT TO DO NOW (cont'd):
3. Select Stage 2 Compliance Monitoring Sites and Develop „ T
IDSE Standard Monitoring Report Due: January
• See Chapter 7, Section 7.3 for guidance on how to select Stage 2 compliance monitoring
sites and write the IDSE report. The number of Stage 2 compliance monitoring sites
required for your system is listed on the attachment on Page 2-40.
• EPA or your state will review your IDSE report and contact you before October 1,
2010 to either let you know your Stage 2 compliance monitoring sites and schedule have
been approved or to discuss necessary changes. If you do not hear anything by this
deadline, consider your plan approved and start preparing for Stage 2 compliance.
4. Continue compliance monitoring for the Stage 1 DBPR until you begin compliance
monitoring for the Stage 2 DBPR.
NEXT STEPS:
You will have additional requirements for Stage 2 compliance. Your system will need to do the
following:
• If you have high levels of DBFs, you may need to make system changes before October
1, 2013 to meet the Stage 2 MCLs. If you buy water, see the Consecutive System
Guidance Manual for more information.
• Develop a Stage 2 compliance monitoring plan before you take your first compliance
sample. If you are a subpart H system and you serve more than 3,300 people, you need
to submit your plan to the state.
• Begin annual or quarterly Stage 2 compliance monitoring during the period starting with
October 2013, according to your Stage 2 compliance monitoring plan.
Reminder:
Your system's monitoring requirements for both the IDSE and Stage 2 compliance monitoring
are based on the population of your system and are listed in the attachment on Pages 2-39 and 2-
40.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-36 January 2006
-------
Standard Monitoring Requirements - Schedule 4 page i of2
Submit Standard
Monitoring Plan
by April! 2008
SubrritlDSE
Report by
July 1, 2010
2006
2007
1
April 1
r
2008
,2009 March 31,
4 w
Conduct Standard
Monitoring
(reconrrended)
2009
2010
>
r
2010
RJe PnorrUgation
This summary sheet is for systems that serve fewer than 10,000 people OR are part of a
combined distribution system where the largest system serves fewer than 10,000 people.
WHAT TO DO NOW:
1. Develop Standard Monitoring Plan Due: April 1, 2008
• See Chapter 7, Section 7.1.3 for guidance on how to develop your IDSE
Standard Monitoring Plan. Your monitoring requirements are also listed A
on the attachment on Page 2-39. /
• Chapter 7 contains plan templates. If you would like an electronic
template, see the IDSE Tool: IDSE Tool
http://www.epa.gov/safewater/disinfection/stage2.
Mail your standard monitoring plan to:
STAGE 2 DBPR
US EPA-IPMC
P O Box 98
Dayton, OH 45401-0098
E-mail to stage2mdbp@epa.gov or submit electronically via the IDSE tool
EPA or your state will review your standard monitoring plan and contact you before April
1, 2009 to either let you know it has been approved or discuss necessary changes. If you do not
hear anything by this deadline, consider your plan approved and start monitoring.
2. Conduct Standard Monitoring | Apr. 1, 2009 - March 31, 2010
Monitoring should be done according to your standard monitoring plan.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-3 7
January 2006
-------
Standard Monitoring Requirements - Schedule 4 page2of2
WHAT TO DO NOW (cont'd):
3. Select Stage 2 Compliance Monitoring Sites and Develop „ T . t ~ft1ft
IDSE Standard Monitoring Report Uue: J"'y lj 2U1U
• See Chapter 7, Section 7.3 for guidance on how to select Stage 2 compliance monitoring
sites and write the IDSE report. The number of Stage 2 compliance monitoring sites
required for your system is listed on the attachment on Page 2-40.
• EPA or your state will review your IDSE report and contact you before October 1,
2010 to either let you know your Stage 2 compliance monitoring sites and schedule have
been approved or to discuss necessary changes. If you do not hear anything by this
deadline, consider your plan approved and start preparing for Stage 2 compliance.
4. Continue compliance monitoring for the Stage 1 DBPR until you begin compliance
monitoring for the Stage 2 DBPR.
NEXT STEPS:
You will have additional requirements for Stage 2 compliance. Your system will need to do the
following:
• If you have high levels of DBFs, you may need to make system changes before October
1, 2013 to meet the Stage 2 MCLs. If you buy water, see the Consecutive System
Guidance Manual for more information.
• Develop a Stage 2 compliance monitoring plan before you take your first compliance
sample. If you are a subpart H system and you serve more than 3,300 people, you need
to submit your plan to the state.
• Begin annual or quarterly Stage 2 compliance monitoring during the period starting with
October 2013 or October 2014, according to your Stage 2 compliance monitoring plan.
Reminder:
Your system's monitoring requirements for both the IDSE and Stage 2 compliance monitoring
are based on the population of your system and are listed in the attachment on Pages 2-39 and 2-
40.
IDSE Guidance Manual for the Final Stage 2 DBPR 2-38 January 2006
-------
Standard Monitoring Requirements - Attachment (For All Schedules)
Page Iof2
IDSE Standard Monitoring Requirements
Source
Water
Type
Subpart H
Ground
Water
Population Size Category1
<500 consecutive systems
<500 non-consecutive
systems
500-3,300 consecutive
systems
500-3,300 non-consecutive
systems
3,301-9,999
10,000-49,999
50,000-249,999
250,000-999,999
1,000,000-4,999,999
> 5,000,000
<500 consecutive systems
<500 non-consecutive
systems
500-9,999
10,000-99,999
100,000-499,999
> 500.000
Monitoring Periods
and Frequency of
Sampling
one (during peak
historical month)3
four (every 90 days)
six (every 60 days)
one (during peak
historical month)3
four (every 90 days)
Distribution System Monitoring Locations2
Total per
monitoring
neriod
2
2
2
2
4
8
16
24
32
40
2
2
2
6
8
12
Near Entry
Points
1
1
1
3
4
6
8
1
1
1
2
Average
Residence Time
1
2
4
6
8
10
1
1
2
High TTHM
Locations
1
1
1
1
2
3
5
8
10
12
1
1
1
2
3
4
High HAAS
Locations
1
1
1
2
4
6
8
10
1
1
2
3
4
1 Your monitoring requirements (locations and frequency) are based on the population served by your system.
2 A dual sample set (i.e., a TTHM and an HAAS sample) must be taken at each monitoring location during each monitoring period.
3 The peak historical month is the month with the highest TTHM or HAAS levels or the warmest water temperature.
IDSE Guidance Manual for the Final Stage 2 DBPR
2-39
January 2006
-------
Standard Monitoring Requirements - Attachment (For All Schedules)
Page 2 of 2
Stage 2 Compliance Monitoring Requirements
Source
Water
Type
Subpart
H
Ground
Water
Population Size
Category1
<500
500-3,300
3,301-9,999
10,000-49,999
50,000-249,999
250,000-999,999
1,000,000-4,999,999
>5,000,000
<500
500-9,999
10,000-99,999
100,000-499,999
>500,000
Monitoring
Frequency2
per year
per quarter
per quarter
per quarter
per quarter
per quarter
per quarter
per quarter
per year
per year
per quarter
per quarter
per quarter
Distribution System Monitoring Location
Total per
monitoring
period3
2
2
2
4
8
12
16
20
2
2
4
6
8
Highest TTHM
Locations
1
1
1
2
3
5
6
8
1
1
2
3
3
Highest HAAS
Locations
1
1
1
1
O
4
6
7
1
1
1
2
O
Existing Stage 1
DBPR Compliance
Locations
1
2
3
4
5
1
1
2
1 Your monitoring requirements (locations and frequency) are based on the population served by your system.
2 All systems must monitor during month of highest DBP concentrations.
3 Systems on quarterly monitoring must take dual sample sets every 90 days at each monitoring location, except for subpart H systems serving
500-3,300. Systems on annual monitoring and subpart H systems serving 500-3,300 are required to take individual TTHM and HAA5 samples
(instead of a dual sample set) at the locations with the highest TTHM and HAA5 concentrations, respectively. Only one location with a dual sample
set per monitoring period is needed if highest TTHM and HAA5 concentrations occur at the same location (and month, if monitored annually).
IDSE Guidance Manual for the Final Stage 2 DBPR
2-40
January 2006
-------
3.0 Very Small System Waiver
This chapter covers:
3.1 Qualifying for the VS S Waiver
3.2 Selecting a Stage 2 Compliance Monitoring Site
3.3 Next Steps: Preparing the Stage 2 DBPR Compliance Monitoring Plan
EPA recognizes that very small systems typically have small distribution systems where
the high total trihalomethane (TTHM) and high haloacetic acid-five (HAAS) levels occur at the
same location. For this reason, systems serving fewer than 500 people are automatically exempt
from IDSE requirements as long as the criteria in Section 3.1 are met, and EPA or your state
does not require otherwise.
If you meet the very small system (VSS) waiver criteria and EPA or your state does
not notify you that you need to conduct an IDSE, your system has NO further
requirements for the IDSE. You will continue Stage 1 compliance monitoring until Stage 2
compliance monitoring starts. If you are in a combined distribution system, you must start
Stage 2 compliance monitoring based on the schedule of the system with the largest population
in your combined distribution system. If you are not in a combined distribution system, you
must start Stage 2 compliance monitoring in 2013 (2014 if you must monitor for
Cryptosporidium under the Long Term 2 Enhanced Surface Water Treatment Rule). See
Chapter 2 for more information on determining your schedule. Refer to Appendix D if you are a
consecutive or wholesale system for specific issues that you should consider.
This chapter discusses the requirements for VSS waivers. These requirements are also
outlined on your requirements summary sheet in Chapter 2 of this manual.
3.1 Qualifying for the VSS Waiver
How can I qualify for the waiver?
To automatically qualify for the VSS waiver, you must serve fewer than 500 people and
have taken TTHM and HAAS samples. VSS eligibility is not dependent on your Stage 1 DBPR
compliance monitoring or other TTHM or HAAS data results. The results do not have to be
below any particular level for you to receive the waiver.
As long as you have TTHM and HAAS data, you are qualified for the VSS Waiver. You have
NO further requirements for the IDSE unless EPA or your state tells you otherwise.
IDSE Guidance Manual for the Final Stage 2 DBPR 3-1 January 2006
-------
Many systems will have Stage 1 DBPR compliance monitoring data that will allow them
to automatically qualify, including those on reduced monitoring. Some systems in combined
distribution systems, however, may not have conducted Stage 1 DBPR compliance monitoring.
These systems can still meet the waiver criteria if they have TTHM and HAAS data. Below is
guidance for systems that have compliance data and those that have operational TTHM and
HAAS data
• Systems with Compliance Data: If you have Stage 1 DBPR compliance data and
have submitted TTHM and HAAS results to your state, you have NO further
requirements unless you hear otherwise from EPA or your state.
Systems with Operational Data: If you have not conducted compliance
monitoring under the Stage 1 DBPR but have other TTHM and HAAS data, you
should contact EPA or your state to determine if this data is sufficient to qualify
for the waiver. Some of the criteria that the reviewer might use to evaluate your
data are:
Were samples analyzed by approved methods?
Were samples analyzed at a certified laboratory?
Are the sites located in areas of maximum residence time?
Were samples taken during the month of warmest water temperature?
Consecutive systems that do not have any TTHM and HAAS data for their system should check
with their wholesaler to determine if the wholesaler collected any TTHM and HAAS data in their
system.
What if EPA or my state contacts me and requires me to conduct an IDSE?
Remember that even if you qualify for the VSS waiver, EPA or your state may require
you to conduct an IDSE. IDSE sampling requirements for systems serving < 500 people are
minor compared to requirements for medium and large systems. Standard monitoring for
systems serving < 500 people consists of preparing a monitoring plan, taking dual sample sets at
two distribution system locations during the peak historical month, and completing an IDSE
report. Refer to the EPA document, IDSE Guide for Systems Serving < 10,000 People, for
guidance on conducting standard monitoring.
3.2 Selecting a Stage 2 DBPR Compliance Monitoring Site
All systems serving <500 people are required to take one TTHM sample at the location
with the highest TTHM concentration, and one HAAS sample at the location with the highest
HAAS concentration. You can collect a dual sample set at one location if the highest TTHM
and HAAS concentrations occur at the same sample location and during the same month.
IDSE Guidance Manual for the Final Stage 2 DBPR 3-2 January 2006
-------
EPA recommends that you consider using your Stage 1 monitoring location for Stage 2
DBPR compliance monitoring it if meets these criteria. If you did not have a Stage 1 compliance
monitoring location, you should work with your state to select the best Stage 2 compliance
monitoring location(s). The high TTHM site will typically be an area of high residence time,
located at an extreme end or isolated portion of the distribution system. The high HAAS site will
often be at the same location, unless you have difficulty maintaining a distribution system
residual.
You should not select high HAAS sites in locations that regularly or in the summer months have
free chlorine residuals less than 0.2 mg/L or with chloramine residuals less than 0.5 mg/L.
3.3 Next Steps: Preparing the Stage 2 DBPR Compliance Monitoring Plan
As the final step before you can begin compliance monitoring for the Stage 2 DBPR, you
must develop a Stage 2 DBPR compliance monitoring plan. The plan will be similar to your
Stage 1 DBPR monitoring plan in that it will identify how you intend to sample for compliance
with Stage 2. You do not need to submit the monitoring plan to EPA or your state, but you must
keep it on file for state and public review. Note that Stage 1 DBPR compliance monitoring
requirements are in effect until you begin Stage 2 DBPR compliance monitoring.
Exhibit 3.1 contains the minimum requirements for what must be included in your Stage
2 DBPR compliance monitoring plan. Because compliance monitoring plans are not addressed
as part of the IDSE provisions of the Stage 2 DBPR, EPA has not included detailed guidance
for developing Stage 2 compliance monitoring plans in this guidance manual. EPA plans to
develop other manuals and training that specifically address the compliance monitoring
provisions of the Stage 2 DBPR.
See EPA's website at http://www.epa.gov/safewater/disinfection/stage2 for an up-to-date
inventory of Stage 2 DBPR guidance manuals and training materials, or call the Safe Drinking
Water Hotline at 1-800-426-4791.
Exhibit 3.1 Required Contents of Stage 2 DBPR Compliance Monitoring Plans
All Systems
Additional Requirements for Consecutive and
Wholesale Systems *
Monitoring locations
Monitoring dates
Compliance calculation
procedures
If your state has used its special primacy authority to
modify your monitoring requirements, you must
include monitoring plans for other systems in your
combined distribution system
1. See Appendix D of this manual for guidance specifically for consecutive and wholesale systems.
IDSE Guidance Manual for the Final Stage 2 DBPR 3-3 January 2006
-------
This page intentionally left blank.
IDSE Guidance Manual for the Final Stage 2 DBPR 3-4 January 2006
-------
4.0 40/30 Certification
This chapter covers:
4.1 Qualification Criteria
4.2 Preparing and Submitting the Certification Letter
4.3 Recordkeeping
4.4 Selecting Stage 2 Compliance Monitoring Sites
4.5 Next Steps: Preparing the Stage 2 DBPR Compliance Monitoring
Plan
Systems can qualify for the IDSE 40/30 certification if they have measured consistently
low total trihalomethane (TTHM) and haloacetic acid-five (HAAS) levels during Stage 1 DBPR
compliance monitoring. The term " 40/30" refers to a system having all individual Stage 1
DBPR compliance samples less than or equal to 0.040 milligrams per liter (mg/L) for TTHM and
0.030 mg/L for HAAS during a specific time period.
If you qualify for the 40/30 certification and comply with the certification
requirements, and EPA or your state does not notify you that you need to conduct an IDSE,
your system has NO further requirements for the IDSE. Your next steps will be to prepare a
compliance monitoring plan and start monitoring for the Stage 2 DBPR. You must continue
with Stage 1 DBPR monitoring until you begin Stage 2 monitoring.
If you have not already done so, complete the flowchart in Exhibit 2.3 of this guidance
manual before reading this chapter. The flowchart directs you to a 2-page Requirements
Summary Sheet which contains compliance dates and additional requirements for complying
with the Stage 2 DBPR. You should keep your requirements summary sheet handy as you work
through this chapter.
This chapter provides guidance on how to prepare and submit a 40/30 certification letter
and select Stage 2 DBPR compliance monitoring sites. If you are a consecutive or wholesale
system, refer to Appendix D for specific issues that you should consider.
IDSE Guidance Manual for the Final Stage 2 DBPR 4-1 January 2006
-------
4.1 Qualification Criteria
To be eligible for 40/30 certification, you must meet all of the following requirements for
the 8 consecutive quarter eligibility period shown in Exhibit 4.1:
• You have TTHM and HAAS data equivalent to what is required by the Stage 1 DBPR
for your system (e.g., quarterly, annual, or every third year)
• No individual sample exceeds 0.040 mg/L for TTHM
• No individual sample exceeds 0.030 mg/L for HAAS
• Your system did not have any TTHM or HAAS monitoring violations
Exhibit 4.1 40/30 Criteria Compliance Dates
Schedule1
1
2
3
4
Stage 1 DBPR
Data Eligibility Period2
8 consecutive calendar quarters
starting no earlier than January 2004
8 consecutive calendar quarters
starting no earlier than January 2005
40/30 Certification
Deadline
October 1 , 2006
April 1 , 2007
October 1 , 2007
April 1 , 2008
Notes:
1. Your schedule is defined by population served by your system or by the largest system in your combined
distribution system. See Chapter 2 for more information.
2. If you were not required to sample during this period, use data from the 12-month period prior to the eligibility
period shown.
Example 4.1 is an example of a system determining whether they meet the 40/30 criteria.
If you don't have Stage 1 compliance data, EPA or your state may allow you to use
operational TTHM and HAAS data to qualify for 40/30 certification if your sampling and
analysis met the general intent of Stage 1 DBPR compliance. Some of the criteria that EPA or
your state might use to evaluate your data are below.
• Were samples analyzed by EPA approved methods?
• Were samples analyzed at a certified laboratory?
• Is the number of sites adequate to represent the distribution system?
• Are the sites located appropriately (average and maximum residence time)?
• Were samples taken during the month of warmest water temperature?
• Were samples taken at the appropriate frequency (monthly, quarterly or annually)?
IDSE Guidance Manual for the Final Stage 2 DBPR 4-2
January 2006
-------
Example 4.1 Qualifying
A ground water system
for a 40/30 Certification
serving 8,000 people with two wells has been sampling annually at
two locations in their distribution system under
or sell water, this system is on schedule 4. The
data for their eligibility
Stage 1 Site 1
Stage 1 Site 2
period.
My 2 1,2005
TTHM
(mg/L)
0.033
0.040
HAAS
(mg/L)
0.015
0.022
No individual sample exceeded 0.040 mg/L for
does not have any TTHM or HAAS
monitoring
the Stage 1
table below
DBPR. Because they do not buy
shows their
July 24, 2006
TTHM
(mg/L)
0.037
0.035
TTHM or 0
HAA5
(mg/L)
0.020
0.021
TTHM and
HAAS
July 23, 2007
TTHM
(mg/L)
0.035
0.037
HAA5
(mg/L)
0.021
0.019
.030 mg/L for HAAS. The system
violations during the eligibility period. The
system determines that they meet the criteria for the 40/30 certification
certification for the period of January 1, 2006 to December
1, 2008.
3 1,2007 by
and they submit their
their deadline of April
Depending on the 8 consecutive quarter eligibility period upon which you are basing
your certification, you may be sampling right before your certification deadline. If this is the
case, you will not know whether you have met the eligibility criteria for 40/30 certification until
these last samples are analyzed. If your TTHM or HAAS results exceed the 40/30 threshold near
the end of the period, you must conduct an IDSE through standard monitoring or a system
specific study (SSS). The deadlines for submittal of a standard monitoring plan or a SSS plan
are the same as the 40/30 certification deadline shown in Exhibit 4.1. Systems may want to
consider preparing a standard monitoring plan if they are concerned that they might exceed the
40/30 levels at the end of the eligibility period.
Remember that even if you meet the eligibility criteria and submit the certification, EPA
or your state may still require you to conduct an IDSE using standard monitoring or an SSS. If
this occurs, you may need to work with EPA or your state to determine a schedule for
completing a standard monitoring or SSS plan and submitting an IDSE report.
IDSE Guidance Manual for the Final Stage 2 DBPR 4-3
January 2006
-------
4.2 Preparing and Submitting the Certification Letter
At a minimum, you must prepare and submit a statement certifying that you meet the
eligibility criteria in Section 4.1. Your certification should also contain basic system information
including population served by your system, your system type (subpart H or ground water,
community or non-community), and contact information. EPA has developed a 40/30
Certification Letter Form (Form 1), shown on the next page, that can be used by any system to
prepare a certification letter. This form is also available electronically as part of the IDSE Tool.
Example 4.2 is a completed certification form for a hypothetical system.
The IDSE Tool creates a custom 40/30 certification form for your system and /
submits the completed letter to EPA and your state for you. The tool is available V
on EPA's website at http://www.epa.gov/safewater/disinfection/stage2. IDSE Tool
You must submit your certification letter by the deadline in Exhibit 4.1. You should
submit the certification to the Information Processing and Management Center (IPMC) for
review by EPA or your state. See Section 1.4 of this guidance manual for information on how to
submit your letter to the IPMC. If you do not submit either a 40/30 certification, standard
monitoring, or study plan by this deadline, you will incur a monitoring and reporting violation.
You can submit the letter as early as you want after you have met the requirements.
EPA or your state may require you to submit additional information listed below:
Stage 1 compliance monitoring results
• A distribution system schematic
• Recommended Stage 2 compliance monitoring locations
If the reviewer wants to request additional information or to have you conduct an IDSE, they
will contact you. However, you may not receive a confirmation that your 40/30 certification has
been accepted. If you do not hear from EPA or your state within 12 months after the submission
deadline, you can assume your certification has been accepted.
4.3 Recordkeeping
You must retain a complete copy of your 40/30 certification letter
on file for 10 years after you submit it to EPA or your state. You must also
make your 40/30 certification letter and any notification from EPA or your
state available for review by your state or the public.
IDSE Guidance Manual for the Final Stage 2 DBPR 4-4
January 2006
-------
[Form 1: 40/30 Certification Letter Page 1 of l|
STAGE 2 DBPR
US EPA-IPMC
P O Box 98
Dayton, OH 45401-0098
System Information
PWS Name: PWS ID:
Street Address: Population Served:
City:
State:
Zip:
Source Water Type: DGround DSubpartH
System Type: QCWS QNTNCWS
Combined Distribution System: DWholesale DConsecutive DNeither
Contact Person
Name: Title:
Phone Number: Fax Number (if available):
Email Address (if available):
Certification
I hereby certify that each individual Stage 1 DBPR compliance sample collected from
to was less than or equal to 0.040 mg/Lfor TTHM and 0.030 mg/Lfor HAAS. I
understand that to be eligible, each individual sample must be equal to or below these values. I
also certify that this PWS collected all required Stage 1 samples and did not have any Stage 1
monitoring violations during this time period.
Signature: Date:
IDSE Guidance Manual for the Final Stage 2 DBPR 4-5 January 2006
-------
Example 4.2 Completed 40/30 Certification Letter Using Form 1
STAGE 2 DBPR
US EPA-IPMC
P O Box 98
Dayton, OH 45401-0098
System Information
PWS Name: Hometown PWS ID: US 1234567
Street Address: 987 Main Street Population Served: 25.976
City: Hometown
State: XX
Zip: 12345
Source Water Type: DGround /'SubpartH
System Type: /CWS DNTNCWS
Combined Distribution System: DWholesale DConsecutive ^Neither
Contact Person
Name: Jim Smith Title: Certified Operator
Phone Number: 987-6543 Fax Number (if available):
Email Address (if available): J.smith@hometown.gov
Certification
I hereby certify that each individual Stage 1 DBPR compliance sample collected from March
2005 to February 2007 was less than or equal to 0.040 mg/Lfor TTHMand 0.030
mg/Lfor HAAS. I understand that to be eligible, each individual sample must be equal to or
below these values. I also certify that this PWS collected all required Stage 1 samples and did
not have any Stage 1 monitoring violations during this time period.
Sisnature: jlim ArruM Date: May 13. 2007
IDSE Guidance Manual for the Final Stage 2 DBPR 4-6 January 2006
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4.4 Selecting Stage 2 Compliance Monitoring Sites
The required number and type of sites for Stage 2 DBPR compliance monitoring are
based on your source water type and the population served by your system. Monitoring
requirements are summarized on the second page of your Requirements Summary Sheet in
Chapter 2 and presented again here in Exhibit 4.2. Keep in mind that even if you qualify for
reduced monitoring under Stage 2 compliance monitoring, you must still select the required
number of monitoring sites as shown in Exhibit 4.2 and include them in your Stage 2 compliance
monitoring plan (see Section 4.5 for a summary of compliance monitoring plan requirements).
Due to the change from plant-based monitoring under the Stage 1 DBPR to population-
based monitoring for the Stage 2 DBPR, you may have the same number, more, or fewer
monitoring sites for Stage 2 compared to Stage 1. Compare your required number of Stage 2
DBPR sites to the total number of Stage 1 DBPR monitoring sites for all plants in your system.
Depending on your findings, go to the appropriate subsection (4.4.1, 4.4.2, or 4.4.3) for guidance
on selecting Stage 2 DBPR compliance monitoring sites.
Exhibit 4.2 Stage 2 Compliance Monitoring Requirements
Source Water
Type
Subpart H
Ground Water
Population Size Category
<500
500-3,300
3,301-9,999
10,000-49,999
50,000-249,999
250,000-999,999
1,000,000-4,999,999
>5.000.000
<500
500-9,999
10,000-99,999
100,000-499,999
>500.000
Monitoring Frequency1
per year
per quarter
per quarter
per quarter
per quarter
per quarter
per quarter
per quarter
per year
per year
per quarter
per quarter
per quarter
Total Number of
Distribution System
Monitoring Locations 2
2
2
2
4
8
12
16
20
2
2
4
6
8
1 All systems must monitor during the month of highest DBP concentration.
2 Systems on quarterly monitoring must take dual sample sets every 90 days at each monitoring location, except for
subpart H systems serving 500-3,300. Systems on annual monitoring and subpart H systems serving 500-3,300 are
required to take individual TTHM and HAAS samples (instead of a dual sample set) at the locations with the highest
TTHM and HAAS concentrations, respectively. Only one location with a dual sample set per monitoring period is
needed if highest TTHM and HAAS concentrations occur at the same location (and month, if monitored annually).
IDSE Guidance Manual for the Final Stage 2 DBPR 4- 7
January 2006
-------
4.4.1 You Have THE SAME Number of Stage 1 Sites as Required by the Stage 2 DBPR
If the number of Stage 1 DBPR monitoring locations in your system is exactly the same
as the required number of Stage 2 DBPR monitoring locations, continue to use all of your Stage
1 DBPR sites for Stage 2 DBPR compliance monitoring.
4.4.2 You Have MORE Stage 1 Sites than Required by the Stage 2 DBPR
If you have more Stage 1 sites than you need for Stage 2 DBPR monitoring (this could be
the case if you have multiple treated entry points in your system), you must select the sites with
highest DBF levels for Stage 2 monitoring. You must alternate your site selection between
locations representing high TTHM levels and high HAAS levels, starting with high TTHM.
To identify locations representing high TTHM levels and high HAAS levels, EPA
recommends that you use Stage 1 DBPR monitoring results. Specifically, you can use the 4-Step
process outlined below:
For systems collecting quarterly data:
LRAA = (Ql + Q2+ Q3 + Q4) / 4
For systems collecting annual data
(once/year):
LRAA = result for warmest
temperature month
Step 1: Calculate the locational running annual
average (LRAA) TTHM and HAAS
concentrations at each Stage 1 DBPR
monitoring site. You should use data
for the most recent calendar year, as
long as this year is generally
representative of typical system
conditions.
Step 2: Select the site with the highest TTHM
LRAA as your first high TTHM site
Step 3: Select the site with the highest HAAS LRAA not previously selected as your first
high HAAS site
Step 4: Repeat Steps 2 and 3, selecting the next highest sites for TTHM and HAAS
respectively, until the total number of selected sites equals the number of sites
required for Stage 2 DBPR compliance monitoring (as shown in Exhibit 4.2)
You can use the site selection Worksheet 4.1 to organize your Stage 1 DBPR data and select
Stage 2 DBPR monitoring sites. If you use this form, you should consider keeping it as part of
your Stage 2 DBPR monitoring plan (see Section 4.5).
IDSE Guidance Manual for the Final Stage 2 DBPR 4-8
January 2006
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Worksheet 4.1 Stage 2 DBPR Site Selection for Systems Getting
the 40/30 Certification Page 1 of 1
Instructions: Enter the site ID and LRAAs for each Stage 1 DBPR monitoring location. You
may want to sort your entries in order by TTHM LRAA or HAAS LRAA values.
As you work through the site selection protocol, fill in the "Stage 2 Site Type" column each
time you select a site to indicate whether the site is a high TTHM or high HAAS site. This will
help you to track which sites have already been selected and can help you ensure that you
select the required number of each type of site.
Stage 1 DBPR
Monitoring Site ID
Example
LRAA
TTHM (mg/L)
0.032
HAAS (mg/L)
0.025
Stage 2 Site Type*
1st high TTHM
* Enter high TTHM or high HAAS site
IDSE Guidance Manual for the Final Stage 2 DBPR 4-9
January 2006
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4.4.3 You Have FEWER Stage 1 Sites than Required by the Stage 2 DBPR
If you do not have enough Stage 1 sites to meet Stage 2 DBPR monitoring requirements
(this could be the case if you are a large system with very few treatment plants), you must select
additional sites. You must identify additional locations by alternating selection of locations
representing high TTHM and high HAAS. Remember that you will need to provide a
justification for the new site selection in your Stage 2 compliance monitoring plan discussed in
Section 4.5 below.
General guidelines for selecting candidate locations for high TTHM and high HAAS sites
are provided below. Guidance for final site selection considering other factors follows. If you
would like more information about formation of disinfection by-products, refer to Appendix A.
In addition, Chapter 7 provides a more in-depth discussion of how to select sites that represent
high levels of TTHM or HAAS.
High TTHM sites
In general, higher water temperatures and increased water age lead to higher TTHM
concentrations. Exhibit 4.3 provides typical characteristics of high TTHM sites. Storage
facilities in a distribution system typically increase water age. Therefore, if your system has
storage tanks or reservoirs, you should locate high TTHM sites downstream of those tanks. In
addition, sites near dead ends and sparsely populated residential areas can be likely sites for high
TTHM. Be sure to locate the sites before or at the last group of customers on a dead end line.
Samples taken at the very end of a dead end line are not representative of the water received by
customers.
Exhibit 4.3 Typical Characteristics of High TTHM Sites
High TTHM sites are often located:
• hydraulically downstream of storage facilities
• near the ends of the distribution system, at or before the last group of customers
• in hydraulic dead-ends, where flow of water is low or stagnant
• prior to the last fire hydrant
Sample sites should not be located:
at a dead-end where there are no customers.
• prior to booster disinfection with chlorine
IDSE Guidance Manual for the Final Stage 2 DBPR 4-10 January 2006
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High HAAS Sites
As with TTHM, higher temperatures and increased residence time can lead to higher
HAAS concentrations. However, HAAS can biodegrade where biological activity is present and
disinfectant residual levels are low or non-existent. Therefore, you should consider locating high
HAAS sites where disinfectant residuals are significantly less than the system average
(indicating a long residence time), but avoid areas that have very low or no residual. When
booster disinfection is applied, the disinfectant residual will increase despite advanced water age.
HAAS levels are likely to increase after a booster disinfectant is applied due to the greater
concentration of disinfectant available to react with DBF precursors and the lack of biological
activity in these areas. Therefore, if your system practices booster disinfection, you should
locate high HAAS sites after booster disinfection is applied.
You should not select high HAAS sites in locations that regularly or in the summer months have
free chlorine residuals less than 0.2 mg/L or with chloramine residuals less than 0.5 mg/L.
Final Site Selection
Once you have considered the likely high TTHM and HAAS locations in your
distribution system, you will choose the best locations for monitoring. Consider the following
issues when making these choices.
Select sites that provide the best geographic and hydraulic representation.
• Make sure that you have located sites in as many key areas as possible. These would
include isolated portions of the distribution system, areas downstream of tanks, areas
downstream of booster chlorination, and within each pressure zone.
• Consider site access issues as each selected site must remain accessible over the long
term.
4.5 Next Steps: Preparing the Stage 2 DBPR Compliance Monitoring Plan
As the final step before you can begin compliance monitoring for the Stage 2 DBPR, you
must develop a Stage 2 DBPR compliance monitoring plan. The plan will be similar to your
Stage 1 DBPR monitoring plan in that it will identify how you intend to sample for compliance
with Stage 2. You must keep your plan on file for state and public review. If you are a subpart
H system serving > 3,300 people, you must also submit your plan to EPA or your state prior to
when you are required to start monitoring.
Exhibit 4.4 contains the minimum requirements for what must be included in your Stage
2 DBPR compliance monitoring plan. Because compliance monitoring plans are not addressed
as part of the IDSE provisions of the Stage 2 DBPR, EPA has not included detailed guidance
for developing Stage 2 compliance monitoring plans in this guidance manual. EPA plans to
develop other manuals and training that specifically address the compliance monitoring
provisions of the Stage 2 DBPR.
IDSE Guidance Manual for the Final Stage 2 DBPR 4-11 January 2006
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See EPA's website at http://www.epa.gov/safewater/disinfection/stage2 for an up-to-date
inventory of Stage 2 DBPR guidance manuals and training materials, or call the Safe Drinking
Water Hotline at 1-800-426-4791.
Exhibit 4.4 Required Contents of Stage 2 DBPR Compliance Monitoring Plans
All Systems
Additional Requirements for
Systems Getting the 40/30
Certification
Additional Requirements
for Consecutive and
Wholesale Systems 1
Monitoring
locations
Monitoring dates
Compliance
calculation
procedures
If you had FEWER Stage 1
DBPR compliance monitoring
sites than required by the
Stage 2 DBPR, you must
include the rationale for
identifying locations as having
high levels of TTHM or HAAS
If your state has used its
special primacy authority
to modify your
monitoring requirements,
you must include
monitoring plans for
other systems in your
combined distribution
system
1. See Appendix D of this manual for guidance specifically for consecutive and wholesale systems.
IDSE Guidance Manual for the Final Stage 2 DBPR 4-12
January 2006
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5.0 System Specific Study Using Existing Monitoring Results
This chapter covers:
5.1 Qualifying for an Existing Monitoring Results SSS
5.2 Preparing Your SSS Plan
A F orm 2: Existing Monitoring Results SSS Plan
5.3 Selecting Stage 2 DBPR Compliance Monitoring Sites and Preparing the
IDSE Report
^D Form 3: IDSE Report for an Existing Monitoring Results SSS
5.4 Recordkeeping
5.5 Next Steps: Preparing the Stage 2 DBPR Compliance Monitoring Plan
This system specific study (SSS) allows systems to avoid duplicating field monitoring
efforts under the Initial Distribution System Evaluation (IDSE) if they already have significant
existing total trihalomethane (TTHM) and haloacetic acid-five (HAAS) data. Some systems may
have operational TTHM and HAAS data beyond what is required by the Stage 1 Disinfectants
and Disinfection Byproducts Rule (DBPR) that will allow them to qualify for this IDSE option.
Other small and medium systems with many plants may be able to qualify using their Stage 1
DBPR data (these systems may have more data for Stage 1 than will be required by the Stage 2
DBPR because of the change from plant-based to population-based monitoring requirements).
Section 5.1 provides the minimum requirements systems must meet to qualify for the existing
monitoring SSS.
If you have not already done so, you should complete the flowchart in Exhibit 2.3 of this
guidance manual. The flowchart will help you select the most appropriate IDSE option for your
system and will direct you to a 2-page Requirements Summary Sheet for your schedule. You
will also be directed to the System Specific Study Requirements - Attachment sheet containing
detailed requirements for Stage 2 compliance monitoring (e.g., number of samples and sampling
frequency). You should keep these sheets handy as you work through this chapter.
This chapter provides guidelines for compiling results, preparing an Existing Monitoring
Results SSS Plan, selecting Stage 2 DBPR compliance monitoring sites, and preparing the IDSE
report. Appendix E supports this chapter by providing an example SSS plan and report for a
surface water system serving 40,000 people.
It is important that consecutive and wholesale systems communicate with each other
throughout the IDSE process. If you are a consecutive or wholesale system, refer to Appendix
D for specific issues that you should consider.
If you plan to conduct an SSS using existing monitoring results, you must submit an SSS
study plan for state or EPA review in accordance with the schedule on your requirements
summary sheet found in Chapter 2. You have the option of submitting the SSS plan and IDSE
-------
report together (which must include selection of Stage 2 DBPR compliance monitoring sites) by
the study plan deadline if all monitoring is complete. If you choose this option, you have no
further requirements under the IDSE unless you are contacted by EPA or your state.
Alternatively, you may submit the SSS plan first, conduct additional monitoring, then submit
your IDSE report for the existing monitoring results SSS by the report deadline in your
requirements summary sheet. Below is a discussion of when you should use each of these two
options.
Option 1: Submitting a Completed Study Plan and IDSE Report at the Same Time
You should consider Option 1 if:
• You have at least as much data as the minimum requirements.
• You believe that your existing data provides good coverage of your system and
adequately identifies locations of high TTHM and HAAS.
You need to:
Select Stage 2 DBPR compliance monitoring locations based on your existing
monitoring results.
Submit both the SSS plan and IDSE report by the deadline for the SSS plan
provided on your requirements summary sheet.
Option 2: Submitting a Separate SSS Plan and IDSE Report
You should consider Option 2 if:
You believe that Stage 1 compliance monitoring data collected during the IDSE
period can help select Stage 2 compliance monitoring sites.
You have additional operational monitoring planned that will aid you in selecting
Stage 2 DBPR compliance monitoring sites.
• Your existing data does not provide good geographic coverage of your system.
You need to:
Submit the SSS plan by the deadline provided on your requirements summary
sheet.
Conduct additional monitoring by the date listed in your requirements summary
sheet.
Select Stage 2 DBPR compliance monitoring sites based on existing and new
monitoring results.
Submit your IDSE report by the deadline in your requirements summary sheet.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-2 January 2006
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5.1 Qualifying for an Existing Monitoring Results SSS
Checklist 5.1 on the next page contains the minimum requirements your system must
meet to qualify for an SSS using existing monitoring results. The data you use to meet the
minimum number of monitoring locations and number of samples must meet the criteria
presented in the checklist. Remember, though, that EPA or your state can still require you to
conduct standard monitoring even if you qualify for the existing monitoring results SSS.
The following sections provide additional guidance for evaluating your data, source
water conditions, and distribution system conditions to determine if you qualify.
5.1.1 Evaluating Existing Monitoring Data
You must have collected at least the total number of TTHM and HAAS samples as
shown in Checklist 5.1. You must also have sampled from the minimum number of locations
shown for your system size and source water type. Your existing monitoring results must
include your Stage 1 DBPR compliance monitoring data. All of the data you use to count
towards these minimum numbers must meet the criteria in the checklist. All data must have been
collected within five years prior to your SSS plan deadline as listed on your requirements
summary sheet found in Chapter 2. See Exhibit 5.1 for the five-year qualifying periods for each
Stage 2 DBPR schedule.
Exhibit 5.1 Qualifying Period for the Existing Monitoring Results SSS
Schedule1
1
2
3
4
SSS Plan Deadline
October 1, 2006
April 1, 2006
October 1, 2007
April 1, 2008
Five- Year Qualifying Period for Existing
Monitoring Results
October 1, 2001 - October 1, 2006
April 1,2001 -April 1,2006
October 1, 2002 - October 1, 2007
April 1,2003 -April 1,2008
Note:
1. Your schedule is defined by population served by your system or by the largest system in your combined
distribution system. You should have received a letter from EPA or your state with your schedule for the Stage 2
DBPR. See Chapter 2 for more information.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-3
January 2006
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Checklist 5.1 Minimum Requirements Checklist for an SSS
Using Existing Monitoring Results
Yes No
D D Do you have at least the minimum number of distribution system monitoring locations
shown in the table below from which you collected TTHM and HAAS samples?
D D Do you have at least the minimum number of TTHM samples and HAAS samples shown in
the table below?
D D Was each monitoring location sampled once during the peak historical month for TTHM,
HAAS, or warmest water temperature for every 12 months of qualifying data submitted?
D D Were all qualifying samples collected and analyzed in accordance with an approved EPA
method and by a certified laboratory?
D D Were all sample results collected no earlier than five years prior to your SSS plan
submission deadline?
D D Have your distribution system and treatment not changed significantly since you collected
your samples?
D D Are your existing monitoring locations representative of your entire distribution system?
If you answered yes to all of the above questions, you meet EPA's minimum requirements for an SSS using
existing monitoring results. Remember, though, that EPA or your state can still require you to conduct standard
monitoring, even if you meet the minimum requirements, or you can choose to conduct standard monitoring.
Source Water
Type
Subpart H
Ground Water
System Size Category
(Population Served)
<500
500-3,300
3,301-9,999
10,000-49,999
50,000-249,999
250,000-999,999
1,000,000-4,999,999
>5,000,000
<500
500-9,999
10,000-99,999
100,000-499,999
>500,000
Minimum Number of
Monitoring Locations
3
3
6
12
24
36
48
60
3
3
12
18
24
Minimum Number of
Samples
TTHM
3
9
36
72
144
216
288
360
3
9
48
72
96
HAAS
3
9
36
72
144
216
288
360
3
9
48
72
96
IDSE Guidance Manual for the Final Stage 2 DBPR 5-4
January 2006
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Each location must have been sampled once during the peak historical month for
TTHM, HAAS, or warmest water temperature for every 12 months of qualifying data. You
should identify your month of high TTHM, high HAAS or warmest water temperature by
reviewing your compliance or other operational data. If you have more than one source in your
system, you should base the peak historical month on the source associated with the highest
TTHM or HAAS formation.
If you have monthly or quarterly TTHM or HAAS data, EPA recommends that you use
these results to identify your peak historical month. You can also evaluate water temperature
data to identify the peak historical month for each year. If the peak historical month for TTHM,
HAAS, or water temperature is different in different years, you should select the month that is
most reflective of your system's normal operating and climatological conditions and use that
month throughout your analysis. You should document the basis for your peak historical month
for TTHM, HAAS, or warmest water temperature in your SSS Plan (See Section 5.2 for
guidance on preparing your SSS plan).
Your existing monitoring results for TTHM and HAAS must have been collected and
analyzed in accordance with an approved EPA method. See Appendix C of this manual for
information on sample collection and approved methods. Your results must have been generated
by a certified laboratory.
If you have several years worth of data during your five-year qualifying period, you can
use different locations sampled in different years to qualify, as long as the data meet all other
criteria for the SSS. Alternatively, you can qualify exclusively with data from one 12-month
period, as long as the 12-month period is within five years prior to your SSS plan deadline. If
you have data that spans more than 12 months, but not 24 months, the data from one peak
historical month can only be used to qualify one 12-month period of data. For example, if you
have collected data from January 2004 through June 2005 and August is your peak historical
month, you may only use data from one 12-month period (e.g., January 2004-January 2005 or
June 2004-June 2005) to count toward your minimum requirements. See Examples 5.1 and 5.2
for how hypothetical systems used their existing monitoring results to qualify for the SSS.
As you evaluate your data, keep in mind that you are required to include all of your
Stage 1 DBPR compliance monitoring data and all other operational TTHM and HAAS
data collected during the time period beginning with the first reported result and ending
with the most recent Stage 1 DBPR results. This includes data that may not meet qualifying
criteria such as samples analyzed by a non-certified laboratory. You must submit this data even
though it does not count toward your minimum number of locations and samples. You should
verify that the qualifying data you submit meet the minimum numbers and criteria for an existing
monitoring results SSS.
See Section 5.1.4 and the instructions for filling out Form 2 in Section 5.2 of this manual
for suggestions for compiling your data.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-5 January 2006
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Example 5.1 Qualifying With Multiple Years of Data Collected From Different
Locations
A surface water system serving 9,000 people has extensive operational DBF data from their
distribution system. Because they purchase water from a wholesale system serving 110,000
people, they are on Schedule 1 for the IDSE, and their SSS plan is due on October 1, 2006.
The system samples quarterly at one location under the Stage 1 DBPR. Below is a description
of their TTHM and HAAS data from their system during the qualifying period (October 1,
2001 - October 1, 2006)
Peak Historical Month for
TTHM, HAA5 or water
temperature:
Special Monitoring Program,
January 2002 through
December 2003:
Special Monitoring Program,
January 2004 through
December 2005:
Stage 1 Compliance
Monitoring, January 2004
through December 2005:
August, based on high TTHM and water temperature
Collected TTHM and HAAS samples quarterly at 4
locations. Monitored during peak historical month for
2002 and 2003.
Total qualifying samples = 32 TTHM
32 HAAS
Collected TTHM and HAAS samples twice per year at 1 of
the previous 4 locations plus 1 new location. Monitored
during peak historical month in 2004 and 2005.
Total qualifying samples = 8 TTHM
8 HAAS
Collected one TTHM and HAAS sample per quarter at the
Stage 1 DBPR compliance monitoring site. Monitored
during peak historical month in 2004 and 2005.
Total qualifying samples = 8 TTHM
8 HAAS
Total Monitoring Locations = 6 (4+1+1)
Total qualifying samples = 48 (32+8+8) TTHM
48 (32+8+8) HAAS
The system has made no significant changes to treatment or the distribution system since the
data were collected. They used certified laboratories and approved methods for all data
collected. This system qualifies for the SSS using existing monitoring results. They plan to
submit both their SSS plan and IDSE report by their plan deadline (October 1, 2006).
IDSE Guidance Manual for the Final Stage 2 DBPR 5-6
January 2006
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Example 5.2 Qualifying Using Data from a One-Year Special Study
A subpart H water system serving 90,000 people serves a geographically diverse community.
They have three springs that are ground water under the direct influence of surface water
(GWUDI) and are each treated at the spring. The system currently monitors quarterly for the
Stage 1 DBPR at 12 distribution system monitoring locations.
This system conducted a detailed study of TTHM and HAAS levels in their system in
calendar year 2003. They monitored quarterly at 16 different locations in their system (in
addition to Stage 1 DBPR compliance monitoring locations) and collected a total of 64
TTHM and HAAS samples. Also during 2003, the system conducted quarterly monitoring at
12 sites for Stage 1 DBPR compliance, generating a total of 48 TTHM and HAAS results.
Dual samples were taken at each site during the peak historical month of July during calendar
year 2003.
Total monitoring locations = 28 (16+12)
Qualifying samples in 2003 = 112 (64+48) TTHM
= 112 HAAS
Qualifying samples in 2004 = 48 TTHM
= 48 HAAS
Qualifying samples in 2005 = 48 TTHM
= 48 HAAS
Qualifying samples in 2006 = 48 TTHM
= 48 HAAS
Total qualifying samples = 256 (112+48+48+48) TTHM
256 (112+48+48+48) HAAS
The system has made no significant changes to treatment or the distribution system since the
data were collected. They used certified laboratories and approved methods for all data
collected. This system qualifies for the SSS using existing monitoring results. They plan to
submit both their SSS plan and IDSE report by their plan deadline (by April 1, 2007).
5.1.2 Evaluating Treatment and Source Conditions
The monitoring results used for your SSS should reflect the source water(s) and treatment
configuration in place at the time that your SSS is completed. Within the period of the SSS data,
temporary changes, such as regular maintenance, rehabilitation, and upgrades of plant processes
are generally acceptable. Temporary changes to disinfection practices are also generally
acceptable within the period of the SSS data. Regular, repeating, and seasonal changes in supply
IDSE Guidance Manual for the Final Stage 2 DBPR 5-7 January 2006
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or treatment are allowable during the SSS qualifying period and should be reflected in data
submitted.
If you made permanent changes to your system that significantly affected relative DBF
formation in the distribution system, only existing monitoring results representing conditions
after the change should be used for your SSS. Treatment changes that affected the magnitude
of TTHM and HAAS levels in the distribution system, but that are unlikely to have changed the
DBF formation rate and relative levels of TTHMs and HAASs in different parts of the system,
are acceptable. For example, improved control of an existing coagulation process or minor
changes in coagulation pH that reduce average levels of DBF precursors are acceptable. If
treatment process or source changes have occurred and data collected prior to the change are
utilized in an SSS, then the use of the data should be justified. An explanation of the change and
a demonstration that the change is unlikely to have significantly affected the relative TTHM and
HAAS levels in the distribution system should be provided. See Appendix A for more
information on factors affecting DBF formation.
5.1.3 Evaluating Distribution System Conditions
Your qualifying data must reflect the overall distribution system hydraulic operation and
large-scale movement of water through your system at the time you submit your SSS plan or
report. Normal daily and seasonal changes in system operation during the data collection period
for the SSS are acceptable. Supply points, pressure zones, large transmission mains, pump
stations, storage tanks, and large wholesale and retail customers should generally be consistent
throughout the data collection period for the SSS and submittal of your study plan and IDSE
report, but do not have to remain exactly the same. A steady increase in water demand over time
that occurs in many systems due to growth is acceptable during the data collection period for the
SSS, if it did not result in major changes in water flow pattern and age within the distribution
system.
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Exhibit 5.2 Examples of System Changes1
Temporary Changes that do not
Significantly Impact DBF Formation
Permanent Changes that are Generally
Considered Cutoff Points for Using
Existing Data
Regular maintenance, rehabilitation,
and upgrades of plant processes
Short duration switches to free
chlorine for secondary disinfection:
• to control nitrification in a
chloraminated system
• for short duration emergencies
• for special disinfection
operations
Adding booster chlorination in the distribution
system
Addition of a new water source
Addition or removal of a very high water use
customer (industrial, institutional, or
wholesale)
Addition, deletion, or replacement of mains or
storage tanks that significantly change water
flow patterns
Large main looping projects that significantly
change water flow patterns
1 Note that this list is not comprehensive—you should use best professional judgement to determine if a modification
to your treatment or distribution system should be considered a cutoff point for the use of existing monitoring
results.
Significant distribution system changes that should be considered as cutoff points for the
use of existing monitoring results include:
• Major, permanent changes in plant production rates, installation or removal of
high service or booster pump stations, or pump operation schemes that
significantly change the location of influence zones of treatment plants and
mixing zones within the distribution system.
Major, permanent changes in water use patterns or system hydraulics.
Specific examples of these types of changes are shown in Exhibit 5.2.
This list is not comprehensive—you should use best professional judgement to determine
if a modification to your distribution system should be considered a cutoff point for the use of
existing monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-9
January 2006
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5.1.4 Compiling Your Data and Calculating LRAAs
You must include all of your existing TTHM and HAAS data (Stage 1 compliance and
operational data) from the first monitoring date that you included through the most recent Stage
1 DBPR compliance monitoring results in your SSS plan and certify that you have not omitted
any data. The Stage 2 DBPR requires all data to be submitted to confirm that there were no
significant or permanent changes to source water quality (swings or shifts) during the monitoring
period that might affect the selection of appropriate Stage 2 compliance monitoring sites.
To organize your data for submission, compile your data into a table or spreadsheet
format. You may wish to use the tables in the SSS plan form in this chapter. You should note
which location IDs are Stage 1 compliance locations. If your locations were monitored at
different time intervals (e.g., twice / year vs. quarterly), consider organizing your data such that
data from your peak historical month lines up vertically.
You should select a repeating 12-month period for your data analysis, and calculate the
annual average at each monitoring site for that time period for every 12-month period of
qualifying data submitted. See the instructions for filling out Form 2 in Section 5.2 for more
suggestions on how to organize your data.
5.2 Preparing Your Existing Monitoring Results SSS Plan
Every system that conducts an SSS using existing monitoring results must prepare and
submit an SSS study plan. You should submit the plan to the Information Processing and
Management Center (IPMC) for review by EPA or your state. See Section 1.4 of this guidance
manual for information on how to submit your plan to the IPMC.
EPA has developed an Existing Monitoring Results SSS Form (Form 2), presented in
this section and available electronically as part of the IDSE Tool. You are not required to use
this form; however, if you choose not to use it, refer to Exhibit 5.3 for a list of the minimum
elements you must include in your SSS study plan.
The IDSE Tool creates a custom form for your system and provides ,A
links to technical guidance from this manual. The tool is available on EPA's (
website at http://www.epa.gov/safewater/disinfection/stage2. IDSE Tool
Your deadline for submitting your study plan can be found on your requirements
summary sheet in Chapter 2. If EPA or your state does not approve or request modifications to
your plan, or notify you that your plan is still under review within 12 months after the deadline
for plan submission, you may consider the plan approved.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-10 January 2006
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Exhibit 5.3 Required Elements of Your SSS Plan
The population served by your system.
Your system type (subpart H or ground water).
All stage 1 DBPR monitoring results and other monitoring results generated
during the time period beginning with the first reported result and ending with
the most recent Stage 1 DBPR compliance results.
Certification that the reported monitoring results include all compliance and non-
compliance results generated during the time period beginning with the first
reported result and ending with the most recent Stage 1 result.
Certification that the samples were representative of the entire distribution
system and that the treatment and distribution system have not changed
significantly since the samples were collected.
A distribution system schematic showing entry points, sources, storage facilities,
and locations and dates of all completed and planned (if applicable) compliance
and non-compliance monitoring.
Identification of your peak historical month for TTHM, HAAS or warmest water
temperature.
The Existing Monitoring Results SSS Plan Form (Form 2) includes the following
sections:
I. General Information
II. SSS Requirements
III. Peak Historical Month
IV. Previously Collected Monitoring Results
V. Certification of Data
VI. Proposed SSS Monitoring Dates
VII. Distribution System Schematic
VIII. Attachments
Sections of the form with an asterisk (*) are required by the Stage 2 DBPR. An example of a
completed form is provided in Appendix E of this guidance manual.
I. General Information
LA. PWS Information* - Important definitions for classifying your system are
provided in the definitions section at the beginning of this guidance manual. If
you have any questions on this section, contact EPA or your state.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-11 January 2006
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PWSID - Enter your PWSID identification number here. This number is typically
assigned by your state.
PWS Name - Enter the name of your system here.
PWS Address - Enter the primary mailing address for your water system here.
Population Served - Enter the number of people served by your PWS.
Remember, this is your RETAIL population served, not including the population
served by consecutive systems that purchase water from you.
System Type - Put a check mark in the appropriate box to identify whether your
system is a CWS or a NTNCWS. Definitions for CWS and NTNCWS can be
found in the definitions section at the beginning of this guidance manual.
Source Water Type - Put a check mark in the appropriate box to identify whether
your system is a subpart H system or a ground water system. If you use any
surface water or GWUDI as a source, mark the subpart H box. Definitions for
subpart H system (including GWUDI) and ground water system can be found in
the definitions section at the beginning of this guidance manual.
Buying/Selling Relationships - Put a check mark in the appropriate box to identify
whether your system is a consecutive system, a wholesale system, or neither. If
you are both a consecutive and wholesale system (e.g., you buy and sell water),
check both boxes. Definitions for consecutive system and wholesale system can
be found in the definitions section at the beginning of this guidance manual and
in Appendix D.
IB. Date Submitted* - Enter either the date that you are submitting the form
electronically, putting it in the mailbox, or dropping it off with an express
delivery service. Be sure to submit your SSS study plan before the deadline
found on your requirements summary sheet.
1C. PWS Operations - This section asks questions about your system to help inform
EPA and state personnel during the plan review process.
Residual Disinfectant Type - Put a check mark in the appropriate box to identify
the type of disinfectant you most often use to maintain a residual in your
distribution system (not necessarily the same disinfectant used for primary
disinfection at the treatment plant). If you use chloramine but switch to free
chlorine for a short time, you should still check chloramine only. If you use
chloramine and chlorine regularly in your system (e.g, 4 months of free chlorine
and 8 months of chloramines), check both chlorine and chloramine. If you
maintain your residual with a disinfectant other than chlorine or chloramines (e.g.,
IDSE Guidance Manual for the Final Stage 2 DBPR 5-12 January 2006
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chlorine dioxide), you should place a check next to the box marked "Other" and
enter the type of disinfectant you use in the blank next to "Other".
Number of Disinfected Sources - Enter the total number of sources that deliver
disinfected water to your distribution system. If you connect to a single
wholesale system at a number of locations in your distribution system, consider
this one purchased source. Multiple wells that are disinfected at a common
treatment plant should also be considered one source. Do not count wells that are
not disinfected or are disinfected by UV only.
ID. Contact Person* - Enter the contact information of the person who is submitting
the form. This should be the person who will be available to answer questions
from EPA and/or the state reviewers.
II. SSS Requirements*
II. A. Minimum Number of Monitoring Locations - Refer to the System Specific Study
Requirements - Attachment sheet in Chapter 2. Copy the numbers from the "SSS
Existing Data - Minimum Sample Requirements" table for the number of
monitoring locations that corresponds to your source type and the population
served by your system.
II.B. Minimum Number of Required Samples - Refer to the System Specific Study
Requirements - Attachment sheet in Chapter 2. Copy the numbers from the "SSS
Existing Data - Minimum Sample Requirements" table for the number of TTHM
and HAAS samples that corresponds to your source type and the population
served by your system.
II.C. IDSE Schedule - Enter the schedule for your system based on the letter sent to
you from EPA or your state. See Chapter 2 for more information on the letter.
III. Peak Historical Month
III. A. Peak Historical Month for TTHM. HAAS or Warmest Water Temperature* -
Enter the month that you determined to be your peak historical month for TTHM,
HAAS or warmest water temperature for your existing monitoring results.
III.B. If Multiple Sources. Source Used to Determine Peak Historical Month - If your
system has only one source, write "N/A" here. If you have more than one source,
write the name of the source you used as the basis for determining peak historical
month. For example, if a system has one surface water, one ground water, and
one purchased ground water source, it is likely that they relied heavily on data
from the surface water source to select their peak historical month. This system
would write "surface water source" in the blank provided.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-13 January 2006
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III.C. Peak Historical Month Based On - Put a check mark in the appropriate box to
identify whether your system used TTHM, HAAS, or warmest water temperature
to determine the peak historical month. If more than one were used, check as
many as necessary. If you used data other than TTHM, HAAS and temperature
data to select your peak historical month (e.g., you used TOC data and/or water
age data), describe how you used additional data here.
IV. Previously Collected Monitoring Results*
IV. A. Where were your TTHM and HAAS samples analyzed? - Put a check mark in the
appropriate box to identify whether your system analyzed TTHM and HAAS
samples in an in-house laboratory or sent the samples to a certified laboratory for
analysis.
If you analyzed your TTHM and HAAS samples in an in-house laboratory, check
the appropriate box to identify whether your laboratory is certified. If you sent
your TTHM and HAAS samples to a certified laboratory, enter the name of the
laboratory in the blank. If you used more than one laboratory (e.g., if you used
different laboratories for operational and compliance samples), list both
laboratories, or check "in-house" and list the name of the laboratory if applicable.
IV.B. What method was used to analyze your TTHM and HAAS samples? Put a check
mark in the appropriate box to indicate the analytical method used to measure
TTHM and HAAS. If more than one method was used (e.g., if you used different
methods for operational and compliance samples), check more than one method.
If you do not know what method was used, contact your laboratory.
IV.C. TTHM Results - Enter the TTHM results for each monitoring site for each
monitoring period in which you collected data. Attach additional copies of this
page if needed. Alternatively, you can use your own format and submit all
monitoring results in an attachment. Guidelines for using the data tables in this
section of Form 2 to report results are provided below.
• If you have multiple years of data at a monitoring location: Select a
repeating 12-month period for your data analysis. You may choose the
calendar year, fiscal year, or other 12-month period. While you can select
any 12-month period, you must include one sample for the peak historical
month for every 12 months of qualifying data submitted. List each
12-month period in a separate row and indicate the 12-month period
during which the data were collected. List multiple years of data for each
monitoring location before continuing to the next monitoring location.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-14 January 2006
-------
• If you have data from one 12-month period at a monitoring location:
Use the 12-month period for which you have collected data, even if you
used a different time period for other monitoring locations.
Enter the site ID for each location, and note which site IDs are Stage 1
compliance locations. If your locations were monitored at different time intervals
(e.g., twice/year vs. quarterly), consider organizing your data such that data from
your peak historical month lines up vertically. For each sample result, enter the
date on which sampling was conducted.
In the column marked "Data Qualifies (yes/no)," indicate whether the data in the
row are qualifying data. To be considered qualifying data, the samples must be
analyzed by a certified laboratory using an approved method, and each location
must be sampled during the peak historical month identified in III. A for each
12-month period of data submitted. See Section 5.1.1 for more information.
Calculate the LRAA for each 12-month period of qualifying data submitted and
enter it in the last column in the table. If you did not monitor on a regular basis,
compute quarterly averages first, then use these values to calculate your LRAA.
If you took a sample once during the peak historical month, then your LRAA is
the single result from your peak historical month.
Appendix E provides an example of how you can present your data.
Remember, you must include all Stage 1 DBPR compliance results and
operational results generated during the time period beginning with the first result
reported for the SSS and ending with the most recent Stage 1 DBPR results.
IV.D. HAAS Results - Enter the HAAS results for each monitoring site for each
monitoring period in which you collected data. For each sample result, enter the
date on which sampling was conducted. Attach additional copies of this page if
needed. Alternatively, you can use your own format and submit all monitoring
results in an attachment.
Use the same 12-month periods you used to report TTHM data under IV.C. Refer
to IV.C. for suggestions on how to organize and report your data.
Remember, you must include all Stage 1 DBPR compliance results and
operational results generated during the time period beginning with the first result
reported for the SSS and ending with the most recent Stage 1 DBPR results.
V. Certification of Data* - Carefully read the criteria listed in this section and review your
system data to verify that each statement is true. If all statements are true, sign your
name and enter the date in the spaces provided.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-15 January 2006
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VI. Proposed SSS Monitoring Schedule* - Skip this section if you are submitting your
IDSE report at the same time as your SSS plan. Complete it only if you plan to conduct
monitoring during the SSS period.
Enter the ID for each monitoring site in the table (verify that these match the IDs you
enter on your schematic), and enter your proposed sampling schedule. The entry can be a
specific date or week and can be in a number of different formats. For example:
7/9/07
2nd week in Nov ' 07
Week of 7/9/07
Be sure to include dates for Stage 1 DBPR monitoring to be conducted during the SSS
period. Remember that at least one monitoring period must be during the peak historical
month identified in Section III. A. for each 12 months of qualifying data. Attach
additional sheets as needed.
VII. Distribution System Schematic* - Attach a distribution system schematic to your SSS
plan. Your schematic must include the locations of entry points, sources, storage
facilities, Stage 1 compliance monitoring sites, and monitoring sites for your existing
results.
SSS plans will not be considered confidential business information (CBI) and are subject
to the Freedom of Information Act (FOIA). Therefore, your distribution system
schematic should not contain information that poses a security risk to your system.
EPA suggests that you consider one of the following options for submitting distribution
system schematics:
• Option 1: Distribution system schematic with no landmarks or addresses
indicated. Show locations of sources, entry points, storage facilities, Stage 1
compliance monitoring locations, and monitoring sites for your existing results
(required). Also include pressure zone boundaries and locations of pump stations.
Provide map scale.
Option 2: City map without locations of pipes indicated. Show locations of
sources, entry points, storage facilities, Stage 1 compliance monitoring locations,
and monitoring sites for your existing results (required). Also include boundaries
of the distribution system, pressure zone boundaries and locations of pump
stations. Provide map scale.
Schematics should be as clear and easy to read as possible. They should typically be
submitted on a scale of between 1:4,000 and 1:8,000; however, larger-scale drawings are
acceptable as long as systems components can still be clearly shown. All sizes from 8!/2
inches x 11 inches to larger, plan-sized sheets are acceptable. If electronic versions are
submitted, use one of the following file types:
IDSE Guidance Manual for the Final Stage 2 DBPR 5-16 January 2006
-------
Adobe PDF file (*.pdf)
• Microsoft Word (*.doc)
• WordPerfect (*.wpd)
Image file (*.gif, *.bmp, *.jpg, *jpeg)
VIII. Attachments - Put a check mark in each of the boxes corresponding to any attachments
that you have included in your report. A distribution system schematic is required. Refer
to Section VII for details.
If you submit your study plan electronically, you also have the option to submit
attachments in hard copy. Include a note in your electronic study plan explaining that
attachments are being submitted in hard copy, and mail the hard copy to the IPMC
mailing address in your Requirements Summary Sheet. The IPMC will match the hard
copy submission with your electronic submission when it is received.
Enter the total number of pages in your monitoring plan (including attachments) in the
blank at the bottom of this section. This will allow EPA or your state to ensure that all
pages were received.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-17 January 2006
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This page intentionally left blank.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-18 January 2006
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Form 2: Existing Monitoring Results SSS Plan pagei
I. GENERAL INFORMATION
A. PWS Information*
PWSID:
PWS Name:
PWS Address:
City:
Population Served:
B. Date Submitted*
State:
Zip:
System Type:
news
D NTNCWS
Source Water Type:
D Subpart H
n Ground
Buying / Selling Relationships:
D Consecutive System
D Wholesale System
D Neither
C. PWS Operations
Residual Disinfectant Type: n Chlorine n Chloramines n Other,
Number of Disinfected Sources: Surface GWUDI Ground
Purchased
D. Contact Person*
Name:
Title:
Phone #:
E-mail:
Fax#:
II. SSS REQUIREMENTS*
A. Minimum Number of Monitoring Locations
B. Minimum Number of Required Samples
TTHM HAAS
C. IDSE Schedule
n Schedule 1 n Schedule 2 n Schedule 3 n Schedule 4
IDSE Guidance Manual for the Final Stage 2 DBPR 5-19
January 2006
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Form 2: Existing Monitoring Results SSS Plan Page20f8
I. PEAK HISTORICAL MONTH
A. Peak Historical Month*
B. If Multiple Sources, Source Used to Determine Peak Historical Month
(write "N/A" if only one source in your system)
C. Peak Historical Month Based On (check as many as needed)
D High TTHM D High HAAS D Warmest Water temperature
If you used other information to select your peak historical month, explain here
(attach additional sheets if needed)
IV. PREVIOUSLY COLLECTED MONITORING RESULTS*
A. Where were your TTHM and HAAS samples analyzed?
n In-House
Is your in-house laboratory certified? n Yes
D No
n Certified Laboratory
Name of certified laboratory:
B. What method(s) was used to analyze your TTHM and HAAS samples?
TTHM HAAS
D EPA 502.2 D EPA 552.1
D EPA 524.2 D EPA 552.2
D EPA 551.1 D EPA 552.3
D SM 6251 B
IDSE Guidance Manual for the Final Stage 2 DBPR 5-20 January 2006
-------
Form 2: Existing Monitoring Results SSS Plan page 3 of s
IV. PREVIOUSLY COLLECTED MONITORING RESULTS (continued)*
C
. TTHM Results
Site ID1
12-
month
period
Data
Qualifies
(yes/no)
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
TTHM (mg/L)
LRAA
1 Verify that site IDs match the site IDs on your distribution system schematic.
Attach additional sheets as needed for previously collected compliance and operational monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
5-21
January 2006
-------
Form 2: Existing Monitoring Results SSS Plan page 4 of s
IV. PREVIOUSLY COLLECTED MONITORING RESULTS (continued)*
C
. TTHM Results
Site ID1
12-
month
period
Data
Qualifies
(yes/no)
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
TTHM (mg/L)
LRAA
1 Verify that site IDs match the site IDs on your distribution system schematic.
Attach additional sheets as needed for previously collected compliance and operational monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
5-22
January 2006
-------
Form 2: Existing Monitoring Results SSS Plan page 5 of s
IV. PREVIOUSLY COLLECTED MONITORING RESULTS (continued)*
D
. HAAS Results
Site ID1
12-
month
period
Data
Qualifies
(yes/no)
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
HAAS (mg/L)
LRAA
1 Verify that site IDs match the site IDs on your distribution system schematic.
Attach additional sheets as needed for previously collected compliance and operational monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
5-23
January 2006
-------
Form 2: Existing Monitoring Results SSS Plan page e of s
IV. PREVIOUSLY COLLECTED MONITORING RESULTS (continued)*
D
. HAAS Results
Site ID1
12-
month
period
Data
Qualifies
(yes/no)
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
HAAS (mg/L)
LRAA
1 Verify that site IDs match the site IDs on your distribution system schematic.
Attach additional sheets as needed for previously collected compliance and operational monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
5-24
January 2006
-------
Form 2: Existing Monitoring Results SSS Plan page?of
V. CERTIFICATION OF DATA*
I hereby certify that:
The reported monitoring results include all compliance and non-compliance
results generated during the time period beginning with the first reported result
and ending with the most recent Stage 1 DBPR results.
The samples are representative of the entire distribution system.
Treatment and the distribution system have not changed significantly since the
samples were collected.
Signature:
Date:
VI. PROPOSED SSS MONITORING SCHEDULE*
Skip if you are submitting your IDSE Report at the same time as your plan
SSS Site ID
(from map)1
Projected Sampling Date (date or week):
period 1
period 2
period 3
period 4
period 5
period 6
1 Verify that site IDs match IDs on your distribution system schematic (See Section VII of this
form). Attach additional copies of this sheet if necessary.
2 period = monitoring period. Can list exact date or week (e.g., week of 7/9/07)
IDSE Guidance Manual for the Final Stage 2 DBPR 5-25
January 2006
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Form 2: Existing Monitoring Results SSS Plan pages of
VII. DISTRIBUTION SYSTEM SCHEMATIC*
ATTACH a schematic of your distribution system.
Distribution system schematics are not confidential and should not contain information that
poses a security risk to your system. EPA recommends that you use one of two options:
Option 1: Distribution system schematic with no landmarks or
addresses indicated. Show locations of sources, entry points, storage
facilities, operational monitoring locations, and Stage 1 compliance
monitoring locations (required). Also include pressure zone boundaries and
locations of pump stations. Provide map scale.
Option 2: City map without locations of pipes indicated. Show
locations of sources, entry points, storage facilities, operational monitoring
locations, and Stage 1 compliance monitoring locations (required). Also
include boundaries of the distribution system, pressure zone boundaries
and locations of pump stations. Provide map scale.
VIM. ATTACHMENTS
D Additional sheets for explaining how you selected the peak historical month
(Section III).
D Additional sheets for previously collected monitoring results (Section IV).
D Additional sheets for proposed monitoring dates (Section VI).
D Distribution system schematic* (Section VII).
Total Number of Pages in Your Plan:
Note: Fields with an asterisk (*) are required by the Stage 2 DBPR.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-26 January 2006
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5.3 Selecting Stage 2 DBPR Compliance Monitoring Sites and Preparing the
IDSE Report
If you submitted your study plan separate from your IDSE report, EPA or your state will
review the plan. If EPA or your state does not approve or request modifications to your plan, or
notify you that your plan is still under review within 12 months after the deadline for plan
submission, you may consider the plan approved. Follow your approved study plan as you
complete SSS monitoring.
Every system that conducts an existing monitoring results SSS must use results from
their SSS to select Stage 2 DBPR compliance monitoring sites. You must follow a specific
protocol, as laid out in the Stage 2 DBPR, to evaluate data and select compliance sites unless
you decide to recommend alternative Stage 2 compliance monitoring sites to your state or EPA.
This section presents the required protocol for selecting Stage 2 DBPR compliance monitoring
sites and provides guidance for preparing an IDSE report.
You must include all additional monitoring results taken during the period of the SSS
and recommended Stage 2 compliance monitoring sites in your IDSE Report. You should
submit your IDSE report to the Information Processing and Management Center (IPMC) for
review by EPA or your state. See Section 1.4 of this guidance manual for information on how to
submit your plan to the IPMC.
You must submit the report by the deadline in your requirements summary sheet
identified in chapter 2. As discussed on page 5-2 of this chapter, you have the option of
submitting your IDSE report with the SSS plan by the plan deadline. In this case, all monitoring
results must be included in your study plan.
EPA has developed a form for the IDSE Report for an Existing
Monitoring Results SSS (Form 3), presented in Section 5.3.3 and available
electronically as part of the IDSE Tool. You are not required to use this form;
however, if you choose not to use it, refer to Exhibit 5.4 for a list of the minimum
elements you must include in your IDSE report. An example of a completed report IDSE T
can be found in Appendix E. The IDSE Tool is available on EPA's website at
http://www.epa.gov/safewater/disinfection/stage2.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-2 7 January 2006
-------
Exhibit 5.4 Required Elements of Your IDSE Report for an Existing Monitoring
Results SSS
• All additional Stage 1 DBPR monitoring results and other monitoring results
generated during the time period of the SSS in tabular or spreadsheet format.
• Recommendations and justifications of Stage 2 DBPR monitoring sites and
sampling dates.
• If changed from your approved study plan,
- Distribution system schematic
- Population
- System type (subpart H or ground water).
• An explanation of any deviations from your approved study plan
5.3.1 Selecting Stage 2 DBPR Compliance Monitoring Locations
Section 5.1.4 provided guidance on compiling data for each Stage 1 compliance site and
each operational site. These results should have been included in your SSS plan. Calculate the
LRAAs for all sites that were monitored since you submitted your SSS plan, including your
Stage 1 monitoring sites. If you are submitting your IDSE report at the same time as your SSS
plan, you do not need to make additional calculations.
You will be starting with the LRAA results for each monitoring location to select Stage 2
compliance monitoring sites. If you have multiple years of data at the same monitoring location,
use the year of data with the highest LRAA for each site. If you monitored at different
frequencies at different locations or in different years, consider using your peak historical month
data to evaluate your monitoring locations. If you do this, ensure your analysis and resulting
recommendation is clear in your justification for each monitoring location. EPA recommends
that you use Worksheet 5.1 to organize your data and select Stage 2 DBPR compliance
monitoring sites.
As noted in the worksheet, you must use the site selection protocol in Exhibit 5.5 to
select your Stage 2 compliance monitoring locations. The number of required Stage 2
compliance monitoring sites for your system can be found on page 2 of the System Specific
Study Requirements - Attachment sheet in Chapter 2. Use qualifying data only as you work
through the protocol. If you complete all steps in the protocol and need additional compliance
monitoring sites for the Stage 2 DBPR, repeat the protocol until the required number of sites has
been selected. If you arrive at Step 3 or Step 7 and have no more Stage 1 DBPR sites from
which to select, continue to the next step. Example 5.3 shows how a system uses the protocol to
select their Stage 2 compliance monitoring sites.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-28 January 2006
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Additional Factors to Consider During Selection of Stage 2 Compliance Monitoring Sites
You may select alternate sites other than those identified using the protocol, but you
must justify the alternate locations in your IDSE report.
In general, TTHM and HAAS LRAAs are the most important factors in site selection.
However, the Stage 2 rule allows for some flexibility in this process. As you work through the
site selection protocol, you should consider other factors that may lead you to select a site with a
similar or slightly lower LRAA. If you do not use your highest TTHM and HAAS LRAAs to
select your Stage 2 compliance monitoring sites, you must provide justification for your
selection in your IDSE report. The following conditions are possible reasons why you may
select a site with a slightly lower LRAA over another site:
• The site provides more complete geographic coverage of the entire distribution
system
The site allows you to maintain a historical record
Sampling at that site provides the opportunity to collect other water quality or
operational data (e.g., chloramine systems may want to collect nitrate or nitrite
data at that site)
EPA recognizes that a slight difference between LRAAs measured at two sites may not
be meaningful given the normal variability that may occur at a site over time. As a result, the
selection of a Stage 2 compliance monitoring site with a slightly lower LRAA may be acceptable
if other factors, such as those listed above, favor the site with the lower LRAA. Examples 5.4
and 5.5 illustrate situations in which hypothetical systems might select Stage 2 DBPR
compliance monitoring sites using criteria other than the site selection protocol. When two sites
have the same LRAA, you should also consider the factors listed above to select the best site for
your Stage 2 compliance monitoring.
You may want to discuss additional site characteristics that make the location suitable for
Stage 2 compliance monitoring. Some characteristics you might consider including in your
justifications are as follows:
Peak historical month data
• Pipe size, or range of pipe sizes in the area
• Relationship to storage facilities
• Estimated water age, if available
• Source of water (if the distribution system is served by more than one source)
It is possible that EPA or your state may not concur with your justification and may require you
to select different Stage 2 compliance monitoring sites.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-29 January 2006
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Worksheet 5.1 Stage 2 DBPR Site Selection Worksheet for an Existing
Monitoring Results SSS Page i of i
Instructions:
1) Enter the number of required Stage 2 DBPR compliance monitoring sites based on your
System Specific Study Requirements -Attachment summary sheet from Chapter 2.
2) Enter the Site ID and LRAA for each Stage 1 compliance monitoring location and each
operational monitoring location. You may want to sort your entries in order by TTHM
LRAA or HAAS LRAA values.
3) As you work through the site selection protocol in Exhibit 5.5, fill in the "Stage 2 Site
Type" column each time you select a site to indicate whether the site is a high TTHM, high
HAA5, Existing Stage 1 DBPR Compliance Monitoring Site, or selected using criteria other
than the protocol.
No. of Stage 2 DBPR Compliance Monitoring Sites Required
Highest TTHM Highest HAA5 Existing Stage
1 TOTAL
Site ID
Example
LRAA
TTHM (mg/L)
0.075
HAAS (mg/L)
0.045
Stage 2 DBPR Site
Type*
Highest TTHM
* Enter Highest TTHM, Highest HAA5, or existing Stage 1 DBPR
IDSE Guidance Manual for the Final Stage 2 DBPR 5-3 0
January 2006
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Exhibit 5.5 Protocol for Selecting Stage 2 DBPR (Subpart V)
Compliance Monitoring Sites
Steps1
[required by rule]
1
2
3
4
5
6
7
8
Select the location with the highest TTHM LRAA
Select the remaining location with the highest HAAS LRAA
For subpart H systems: Select the remaining existing Stase 1
DBPR average residence time compliance monitoring location
with the highest HAAS LRAA
For ground water systems: Select the remaining existing Stage 1
DBPR maximum residence time compliance monitoring location
with the highest HAAS LRAA
Skip this step if you have no more Stage 1 DBPR sites
Select the remaining location with the next highest TTHM
LRAA.
Select the remaining location with the next highest TTHM LRAA
Select the remaining location with the next highest HAAS LRAA
For subpart H systems: Select the remaining existing Stage 1
DBPR average residence time compliance monitoring location
with the highest TTHM LRAA
For ground water systems: Select the remaining existing Stage 1
DBPR maximum residence time compliance monitoring location
with the highest TTHM LRAA
Skip this step if you have no more Stage 1 DBPR
Select the remaining location with the next highest HAAS LRAA
Stage 2 Compliance Monitoring Sites
Selected 2
1st highest TTHM site
1st highest HAAS site
1st Stage 1 DBPR site
2nd highest TTHM site
3rd highest TTHM site
2nd highest HAAS site
2nd Stage 1 DBPR site
3rd highest HAAS site
If you need more Stage 2 DBPR compliance monitoring locations, Go back to Step 1 of this protocol and repeat the
steps until you have selected the required number of total sites.
1. All steps are based on your calculated LRAAs for your operational sites and Stage 1 DBPR compliance
monitoring sites. This means that your existing Stage 1 DBPR sites can be selected in steps other than 3 or 7. Stop
when you reach your required number of Stage 2 DBPR compliance monitoring sites.
2. You cannot select the same site as a highest TTHM and a highest HAAS compliance monitoring site.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-31
January 2006
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E:
A
results SS
ground w
system ha
Specific £
Stage 2 ci
•
•
•
The table
complian
monitorin
sample 5.3 Selecting Stage 2 DBPR Compliance Monitoring Sites
consecutive system serving 15,000 people has completed an existing monitoring
S for the IDSE. This system purchases disinfected ground water from a number of
ater systems drawing from the same aquifer. Based on state determination, the
s two Stage 1 DBPR compliance monitoring sites. According to the System
itudy - Attachment sheet in Chapter 2, the system must select the following four
3mpliance monitoring sites from operational monitoring and Stage 1 DBPR sites:
2 highest TTHM sites,
1 highest HAAS site, and
1 maximum residence time site from the existing Stage 1 DBPR data.
below lists the maximum TTHM and HAAS LRAAs for the Stage 1 DBPR
;e monitoring sites and operational monitoring data submitted for the existing
g results SSS.
Site Number and
Description
Maximum TTHM LRAA
(mg/L)
Maximum HAAS LRAA
(mg/L)
Stage 1 DBPR Compliance Monitoring Results:
1
2
0.058
0.052
0.031
0.046
Operational Monitoring Results:
3
4
5
6
7
8
9
10
11
12
0.053
0.056
0.051
0.047
0.045
0.049
0.038
0.035
0.021
0.022
0.040
0.032
0.042
0.038
0.036
0.039
0.034
0.026
0.015
0.019
IDSE Guidance Manual for the Final Stage 2 DBPR 5-32
January 2006
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Example 5.3 Selecting Stage 2 DBPR Compliance Monitoring Sites (cont.)
The water system used the site selection protocol in Exhibit 5.5 to select their compliance
monitoring sites.
Go to Step 1: Select the Highest TTHMLRAA Site
Site 1 has the highest TTHM LRAA and is selected as the first high TTHM site.
Go to Step 2: Select the Highest HAAS LRAA Site
Site 2 has the highest HAAS LRAA and has not already been selected. Therefore,
Site 2 is chosen as the first high HAAS site.
Go to Step 3: Select the Stage 1 Maximum Residence Time Site with the Highest HAAS LRAA
There are no remaining Stage 1 sites to select from. Skip this step and go to Step 4.
Go to Step 4: Select the Next Highest TTHMLRAA Site
Site 4 has the next highest TTHM LRAA and is therefore chosen as the next highest
TTHM site.
Go to Step 5: Select the Next Highest TTHMLRAA Site
Site 3 has the next highest TTHM LRAA and is therefore chosen as the next highest
TTHM site.
Final Inventory of Stage 2 DBPR Compliance Monitoring Sites*
Highest TTHM: Site 1, Site 3, Site 4 (3 sites)
Highest HAAS: Site 2 (1 site)
Existing Stage 1 DBPR Site (as described in Step 3): No sites
TOTAL Sites = 4
*Note that the requirements on the previous page are for 2 highest TTHM sites, 1 highest
HAAS site, and 1 maximum residence time site from existing Stage 1 DBPR data. However,
because the two Stage 1 DBPR sample sites were the highest TTHM site and the highest
HAAS site, these sites were selected during the first two steps of the selection protocol. As a
result, there were no remaining Stage 1 DBPR sites to choose from during Step 3. Step 3 was
skipped and the remaining two Stage 2 compliance sites were chosen using Steps 4 and 5.
Based on the data collected, the system seems to have chosen its Stage 1 DBPR sites well in
terms of sampling at locations with the highest TTHM and HAAS levels.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-33 January 2006
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A
sites. Th<
one Stage
be selecte
operation
A
the Stage
system ch
maintain
Example 5.4 Maintaining a Historical Record
ground water system serves 90,000 people and must select four Stage 2 compliance
i system has already selected one highest TTHM site, one highest HAAS site, and
1 maximum residence time site with the highest HAAS LRAA. The fourth site to
d is a high TTHM site which must be selected from the Stage 1 DBPR sites and
al sites not yet selected. The table below lists three remaining high-TTHM sites
Site Number and Description
4 (operational site)
8 (operational site)
9 (Stage 1 DBPR max residence time site)
LRAA
TTHM (mg/L)
0.072
0.065
0.070
HAAS
(mg/L)
0.051
0.056
0.051
mong the three remaining high sites, Site 4 has the highest TTHM LRAA. However,
1 DBPR site has only slightly lower TTHM LRAA than operational Site 4. The
looses the Stage 1 DBPR site over site 4 for the Stage 2 high TTHM site to
the historical DBF record at that site.
Example 5.5 Providing Geographic Coverage When Choosing Stage 2 Sites
In general, two representative high TTHM sites should not be located in the same
general area of the distribution system. Consider the following example:
The two highest TTHM LRAAs in the
distribution system are from adjacent historical
sample sites (sites A and B). The site with the third
highest TTHM LRAA is on the far side of the
distribution system (site C). In this case, consider
selecting sites A and C or B and C as Stage 2 sites
for a broader geographical coverage of the
distribution system.
Water Treatment Plant
IDSE Guidance Manual for the Final Stage 2 DBPR 5-34
January 2006
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5.3.2 Determining Your Stage 2 DBPR Compliance Monitoring Dates
The first step in selecting your Stage 2 DBPR compliance monitoring dates is to select
the peak historical month. According to the Stage 2 DBPR, you must conduct Stage 2 DBPR
compliance monitoring during the peak historical month for TTHM or HAAS. You should use
the peak historical month selected in your SSS plan unless new data suggest another month. If
your high TTHM and high HAAS data occur in different months, you should consider which
contaminant is of more concern. If one contaminant clearly shows a higher overall trend and is
closer to the MCL, you should choose the month in which that contaminant is highest.
You must conduct Stage 2 DBPR compliance monitoring during the peak historical
month. If you are a ground water system that serves more than 9,999 people or you are a surface
water system that serves more than 499 people, you must also conduct Stage 2 compliance
sampling at 90 day intervals before and/or after the peak historical month.
The intent of the required time interval is to ensure that samples are representative of the
quality of water over an extended period and do not over-emphasize either high or low
concentrations of TTHM or HAAS that might occur seasonally. For example, a system on
quarterly monitoring could sample in the third full week of every third month. It is not
necessary to sample all sites on the same day.
5.3.3 Preparing the IDSE Report
Every system that conducts an SSS for Existing Monitoring must prepare and submit an
IDSE Report for an Existing Monitoring Results SSS. You should submit the report to the
Information Processing and Management Center (IPMC) for review by EPA or your state. See
Section 1.4 of this guidance manual for information on how to submit your report to the IPMC.
EPA has developed a form for the IDSE Report for an Existing Monitoring SSS
(Form 3), presented in this section and available electronically as part of the IDSE Tool. You
are not required to use this form; however, if you choose not to use it, refer to Exhibit 5.4 for a
list of the minimum elements you must include in your IDSE report.
The IDSE Tool creates a custom form for your system and provides links A
to technical guidance from this manual. The tool is available on EPA's website at (
http://www.epa.gov/safewater/disinfection/stage2. ,DSE T .
Before you begin Stage 2 DBPR compliance monitoring, you will also be required to
prepare a Stage 2 DBPR compliance monitoring plan. In addition, if you are a subpart H system
serving >3,300 people, you must submit a copy of your Stage 2 compliance monitoring plan to
the state. If you include compliance calculation procedures in your IDSE report, the report can
IDSE Guidance Manual for the Final Stage 2 DBPR 5-35 January 2006
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meet the requirement of the plan, and you do not have to prepare or submit a separate plan. As a
guide for specifying your compliance calculation procedures, refer to the Stage 1 DBPR,
141.133(b), and your Stage 1 compliance monitoring plan. Check with your state, as they may
have different requirements under the Stage 2 DBPR. If you are a consecutive or wholesale
system, your state may choose to use its special primacy authority to modify your Stage 2
compliance monitoring requirements. In this case, you should check with the state to see if they
are going to use this authority. You should develop your IDSE report for the total number of
required Stage 2 compliance locations for your system.
The IDSE report for an Existing Monitoring Results SSS form includes the following
sections:
I. General Information
II. Stage 2 DBPR Requirements
III. Additional SSS and Stage 1 Compliance Monitoring Results
IV. Justification of Stage 2 DBPR Compliance Monitoring Sites
V. Peak Historical Month
VI. Proposed Stage 2 Compliance Monitoring Schedule
VII. Distribution System Schematic
VIII. Attachments
If you are submitting an SSS plan and IDSE report at the same time, you must submit the
portions listed in bold above. The rest of this section provides guidance on the completion of
this form.
I. General Information
LA. PWS Information* - If nothing has changed since you completed your modeling
study plan, copy information from your plan into this section. If your system
characteristics have changed, see Section 5.2 of this chapter for guidance on
completing this section.
IB. Date Submitted* - Enter either the date that you are submitting the form
electronically, putting it in the mailbox, or dropping it off with an express
delivery service. Be sure to submit your IDSE report before the deadline found
on your requirements summary sheet.
1C. PWS Operations - This section asks questions about your system to help inform
EPA and state personnel during the plan review process. If nothing has changed
since you completed your modeling study, copy information from your plan into
this section. If your system characteristics have changed, see Section 5.2 of this
chapter for guidance on completing this section.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-36 January 2006
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ID. Contact Person* - Enter the contact information of the person who is submitting
the report. This should be the person who will be available to answer questions
from EPA and/or the state reviewers.
II. Stage 2 DBPR Requirements*
II. A. Number of Required Stage 2 DBPR Compliance Monitoring Sites - Refer to the
System Specific Study Requirements - Attachment in Chapter 2. Copy the
numbers from the "Stage 2 Compliance Monitoring Requirements" table that
correspond to your source type and the population served by your system.
II.B. IDSE Schedule -This should be the same schedule you entered for your modeling
study plan. See Section 5.2 of this chapter for guidance.
II.C. Required Stage 2 DBPR Compliance Monitoring Frequency - Refer to the
System-Specific Study Requirements - Attachment in Chapter 2. Locate the
monitoring frequency from the "Stage 2 Compliance Monitoring Requirements"
table that corresponds to your source type and the population served by your
system. Put a check mark in the box corresponding to that monitoring frequency.
III. Additional SSS and Stage 1 Compliance Monitoring Results*
Skip this section if you are submitting your IDSE Report at the same time as your
SSS plan. If you are submitting additional data with your IDSE report, complete
this section. See the instructions for Form 2 part IV in Section 5.2 of this
guidance manual..
IV. Justification of Stage 2 DBPR Compliance Monitoring Sites*
Enter the site ID from the distribution schematic and the site type (whether it is
highest TTHM, highest HAAS, Stage 1 DBPR, or a site selected using criteria
other than the site selection protocol). An example of how you might justify a
site is given below. For example:
2nd Highest TTHM Site
An example of how you might justify a site that was not selected using the
protocol is below:
Among the three remaining high TTHM sites, operational Site 4 has the highest
TTHMLRAA. However, Stage 1 DBPR Site 7 has only a slightly lower TTHM
LRAA than operational Site 4. Therefore, we choose Stage 1 DBPR Site 7 over
operational site 4 to maintain the historical DBF record.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-3 7 January 2006
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Note that there is only space for 8 monitoring sites on this sheet. If you are a
subpart H system serving more than 249,999 people you are required to monitor
at more than 8 sites. Therefore, you will need to attach additional sheets.
V. Peak Historical Month
V. A. Peak Historical Month* - Enter the month that you determined to be your peak
historical month for TTHM or HAAS.
V.B. Is Your Peak Historical Month the Same as in Your System Specific Study Plan?
- Put a check mark in the appropriate box to identify whether your system used
the same peak historical month as in your SSS plan. If you selected a new peak
historical month based on additional monitoring or other data, explain the basis
for your selection here.
VI. Proposed Stage 2 DBPR Compliance Monitoring Schedule*
Enter the ID for each Stage 2 DBPR compliance monitoring site in the table (verify that
these match the IDs you enter in Section IV and on your schematic). Enter your
proposed sampling schedule for the number of monitoring periods identified in Section
II.C. The entry can be a specific date or week and can be in a number of different
formats. For example:
7/9/07
2nd week in Nov ' 07
Week of 7/9/07
Remember that at least one monitoring period must be during the peak historical month
identified in Section V.A. Note that there is only space for 8 monitoring sites on this
sheet. If you are a subpart H system serving more than 249,999 people you are required
to monitor at more than 8 sites. Therefore, you will need to attach additional sheets.
VII. Distribution System Schematic*
If you are submitting an IDSE report at the same time as your SSS plan, skip this section.
A distribution system schematic is required only if it has changed from your SSS plan. If
it has changed, you must attach a distribution system schematic. See Section 5.2 of this
manual for guidance.
VIII. Attachments - Put a check mark in each of the boxes corresponding to any attachments
that you have included in your report.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-38 January 2006
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Note that there is only space for 8 Stage 2 DBPR compliance monitoring sites and
monitoring schedule in Sections IV and VI. If you are a subpart H system serving more
than 249,999 people, you are required to monitor at more than 8 sites. Therefore, you
will need to attach additional sheets.
Note that a schematic is required only if it has changed from your approved SSS study
plan.
If you deviated from your approved study plan, you must attach an explanation of all
deviations.
If you submit your IDSE report electronically, you also have the option to submit
attachments in hard copy. Include a note in your electronic IDSE report explaining that
attachments are being submitted in hard copy, and mail the hard copy to the IPMC
mailing address in your Requirements Summary Sheet. The IPMC will match the hard
copy submission with your electronic submission when it is received.
If you are a subpart H system serving >3,300 people, you must submit a copy of your
Stage 2 compliance monitoring plan to the state. If you include compliance calculation
procedures in your IDSE report, the report can meet the requirement of the plan, and you
do not have to prepare or submit a separate plan. As a guide for specifying your
compliance calculation procedures, refer to the Stage 1 DBPR, 141.133(b), and your
Stage 1 compliance monitoring plan. Check with your state, as they may have different
requirements under the Stage 2 DBPR.
Enter the total number of pages in your IDSE report (including attachments) in the blank
at the bottom of this section. This will allow EPA or your state to ensure that all pages
were received.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-39 January 2006
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Form 3: IDSE Report for an Existing Monitoring
ReSUltS SSS Page 1 of 7
I. GENERAL INFORMATION
(Skip this section if you are submitting the plan and report at the same time)
A. PWS Information*
PWSID:
PWS Name:
PWS Address:
City:
Population Served:
B. Date Submitted*
State:
Zip:
System Type:
news
D NTNCWS
Source Water Type:
D Subpart H
n Ground
Buying / Selling Relationships:
D Consecutive System
D Wholesale System
D Neither
C. PWS Operations
Residual Disinfectant Type: n Chlorine n Chloramines n Other
Number of Disinfected Sources: Surface GWUDI Ground Purchased
D. Contact Person*
Name:
Title:
Phone #:
E-mail:
Fax#:
II. STAGE 2 DBPR REQUIREMENTS*
A. Number of Required Stage 2 DBPR Compliance Monitoring Sites TOTAL
Highest TTHM Stage 1 DBPR Highest HAAS
IDSE Guidance Manual for the Final Stage 2 DBPR 5-41
January 2006
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Form 3: IDSE Report for an Existing Monitoring
ReSUltS SSS Page2of7
II. STAGE 2 DBPR REQUIREMENTS (continued)*
B. IDSE Schedule C. Required Stage 2 DBPR Compliance Monitoring
Frequency
D Schedule 1 n During peak historical month (1 monitoring period)
D Schedule 2 n Every 90 days (4 monitoring periods)
D Schedule 3
n Schedule 4
III. ADDITIONAL SSS AND STAGE 1 COMPLIANCE MONITORING RESULTS*
(Skip this section if you are submitting the plan and report at the same time)
A. Where were your TTHM and HAAS samples analyzed?
n In-House
Is your in-house laboratory certified? D Yes n No
n Certified Laboratory
Name of certified laboratory:
B. What method(s) was used to analyze your TTHM and HAAS samples?
TTHM HAAS
D EPA 502.2 D EPA 552.1
D EPA 524.2 D EPA 552.2
D EPA 551.1 D EPA 552.3
D SM 6251 B
IDSE Guidance Manual for the Final Stage 2 DBPR 5-42 January 2006
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Form 3: IDSE Report for an Existing Monitoring Results SSS pages of?
III. ADDITIONAL SSS AND STAGE 1 DBPR MONITORING RESULTS (Continued)*
C.
TTHM Results
Site ID1
12-
month
period
Data
Qualifies
(yes/no)
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
TTHM (mg/L)
LRAA
1 Verify that site IDs match the site IDs in your SSS Plan.
Attach additional sheets as needed for SSS and Stage 1 DBPR results.
IDSE Guidance Manual for the Final Stage 2 DBPR
5-43
January 2006
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Form 3: IDSE Report for an Existing Monitoring Results SSS page 4 of?
III. ADDITIONAL SSS AND STAGE 1 DBPR MONITORING RESULTS (Continued)*
D.
HAAS Results
Site ID1
12-
month
period
Data
Qualifies
(yes/no)
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
HAAS (mg/L)
LRAA
1 Verify that site IDs match the site IDs in your SSS Plan.
Attach additional sheets as needed for SSS and Stage 1 DBPR results.
IDSE Guidance Manual for the Final Stage 2 DBPR
5-44
January 2006
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Form 3: IDSE Report for an Existing Monitoring Results
SSS Page 5 of 7
IV. JUSTIFICATION OF STAGE 2 DBPR COMPLIANCE MONITORING SITES*
Stage 2
Compliance
Monitoring
Site ID
Site Type
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
Justification
Attach additional copies of this sheet if you need more room.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-45
January 2006
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Form 3: IDSE Report for an Existing Monitoring
ReSUltS SSS Page6of7
V. PEAK HISTORICAL MONTH
A.
B.
Peak Historical Month*
Is Your Peak Historical Month the Same as in Your SSS Plan?
D Yes D No
If no, explain how you selected your new peak historical month (attach
additional sheets if needed):
VI. PROPOSED STAGE 2 DBPR COMPLIANCE MONITORING SCHEDULE*
Stage 2
Compliance
Monitoring
Site ID
Projected Sampling Date (date or week)1
period 1
period 2
period 3
period 4
1 period = monitoring period. Complete for the number of monitoring periods from
Section II. C.
Attach additional copies of this sheet if you need more room.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-46
January 2006
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Form 3: IDSE Report for an Existing Monitoring
ReSUltS SSS Page 7 of 7
VII. DISTRIBUTION SYSTEM SCHEMATIC*
(Skip this section if you are submitting the plan and report at the same time)
ATTACH a schematic of your distribution system if it has changed since you submitted
your Existing Monitoring Results SSS Plan (Form 2).
VIM. ATTACHMENTS
D Additional sheets for Additional SSS Monitoring Results (Section III).
D Additional sheets for Stage 2 DBPR Monitoring Sites (Section IV). REQUIRED if you
are a subpart H system serving more than 249,999 people.
D Additional sheets for explaining how you selected the peak historical month (Section
V).
D Additional sheets for proposed compliance monitoring dates (Section VI). REQUIRED if
you are a subpart H system serving more than 249,999 people.
D Explanation of deviations from approved study plan.
D Distribution system schematic* (Section VII). REQUIRED if it has changed from your
approved SSS plan.
D Compliance calculation procedures (for Stage 2 Compliance Monitoring Plan).
Total Number of Pages in Your Report:
Note: Fields with an asterisk(*) are required by the Stage 2 DBPR.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-4 7 January 2006
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5.4 Recordkeeping
The IDSE SSS report must be kept on file for 10 years after
the date it is submitted. If EPA or your state modifies the
recommendations made in your report or approves alternative
Stage 2 DBPR compliance monitoring locations, you must also
keep a copy of EPA or your state's notification on file for 10 years
after the date of the notification. You must make your IDSE
report and any notification available for review by your state or
the public.
The SSS plan, including any modifications by EPA or your
state, must also be kept on file for as long as you are required to
retain your IDSE SSS report. You must make the plan and any
modifications available for review by your state or the public.
5.5 Next Steps: Preparing the Stage 2 DBPR Compliance Monitoring Plan
As the final step before you can begin compliance monitoring for the Stage 2 DBPR, you
must develop and implement a Stage 2 DBPR monitoring plan by the deadline provided in
your requirements summary sheet. The plan will be similar to your Stage 1 DBPR monitoring
plan in that it will identify how you intend to sample for compliance with Stage 2. You must
keep your plan on file for state and public review. If you are a subpart H system serving >
3,300 people, you must submit your plan to EPA or your state prior to when you are required to
start monitoring.
Exhibit 5.6 contains the minimum requirements for what must be included in your Stage 2
DBPR compliance monitoring plan. Because compliance monitoring plans are not addressed as
part of the IDSE provisions of the Stage 2 DBPR, EPA has not included detailed guidance for
developing Stage 2 compliance monitoring plans in this guidance manual. EPA plans to
develop other manuals and training that address the compliance monitoring provisions of the
Stage 2 DBPR.
See EPA's website http://www.epa.gov/safewater/disinfection/stage2 for an up-to-date
inventory of Stage 2 DBPR guidance manuals and training materials, or call the Safe Drinking
Water Hotline at 1-800-426-4791.
IDSE Guidance Manual for the Final Stage 2 DBPR 5-49
January 2006
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Exhibit 5.6 Required Contents of Stage 2 DBPR Compliance Monitoring Plans
All Systems
Additional Requirements for Consecutive and
Wholesale Systems l
Monitoring locations
Monitoring dates
Compliance calculation
procedures
If your state has used its special primacy
authority to modify your monitoring
requirements, you must include monitoring plans
for other systems in your combined distribution
system
1. See Appendix D of this manual for guidance specifically for consecutive and wholesale systems
IDSE Guidance Manual for the Final Stage 2 DBPR 5-50
January 2006
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6.0 System Specific Study Using a Distribution System Hydraulic Model
This chapter covers:
6.1 Minimum Model Requirements and Calibration
6.2 Modeling Analysis
6.3 Determining SSS Monitoring Requirements and Schedule
6.4 Preparing your Modeling Study Plan
^D Form 4: Modeling Study Plan
6.5 Selecting SSS Monitoring Sites and Conducting Monitoring
6.6 Selecting Stage 2 DBPR Compliance Monitoring Sites and Schedule
6.7 Preparing the IDSE Report
A Form 5: IDSE Report for a Modeling SSS
6.8 Recordkeeping
6.9 Next Steps: Preparing the Stage 2 DBPR Compliance Monitoring
Plan
One of two options for the system specific study (SSS) involves the use of a detailed,
comprehensive, and well-calibrated distribution system hydraulic model to help select Stage 2
DBPR compliance monitoring locations. Systems using a distribution system hydraulic model
will be required to submit a modeling study plan and IDSE Report describing the modeling
analysis, selection of monitoring sites, and sampling data.
Distribution system hydraulic models can be used for the SSS provided the minimum
model requirements are met. An overview of requirements is given in Exhibit 6.1 and detailed
guidance is provided in Section 6.1 The option of using a distribution system hydraulic model is
intended to allow systems that have models to use their existing technical resources to perform
the IDSE. For many systems, developing a detailed and well-calibrated distribution system
hydraulic model from scratch and training staff to use it could cost more than conducting
standard monitoring (see Chapter 7). If the model will be used for other purposes after the
completion of the SSS, such as optimizing system operations and prioritizing capital
improvements, then the cost of the model development may be justified. If a system's existing
model does not meet the minimum requirements in Exhibit 6.1 at the beginning of the IDSE
period, the system may be able to upgrade the model to complete the modeling SSS or instead
use it in combination with other data and/or analyses for selecting sites for standard monitoring
(see Chapter 7). Exhibit 6.2 includes a list of minimum reporting requirements for the modeling
SSS.
IDSE Guidance Manual for the Final Stage 2 DBPR 6-1 January 2006
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Exhibit 6.1 Minimum Distribution System Hydraulic Model Requirements
To meet the minimum model requirements, your model must include:
Physical System Data
• At least 50 percent of total pipe length in the distribution system.
• At least 75 percent of the pipe volume in the distribution system.
• All 12-inch diameter and larger pipes.
All 8-inch diameter and larger pipes that connect pressure zones, mixing zones
from different sources, storage facilities, major demand areas, pumps, and control
valves, or are known or expected to be significant conveyors of water.
All 6-inch diameter and larger pipes that connect remote areas of a distribution
system to the main portion of the system or are known or expected to be significant
conveyors of water.
• All storage facilities, with controls or settings applied to govern the open/closed
status of the facility that reflect standard operations.
All active pump stations, with realistic controls or settings applied to govern their
on/off status that reflect standard operations.
All active control valves or other system features that could significantly affect the
flow of water through the distribution system (e.g., interconnections with other
systems, pressure reducing valves between pressure zones).
Demand Data
• Extended period simulation with representative diurnal variations in demand
»• Represent total system demand for the peak month of TTHM formation
Calibration
A calibration verification using data for the peak month of TTHM formation and
current system configuration
> Operational controls to represent typical operation during the peak month of
TTHM formation
• Evaluation of actual system performance compared to modeled performance at all
storage facilities in the system
Ability to complete all required calibration no later than 12 months after your
required plan submission date
Modeling Analysis
• The ability to simulate water age during the peak month of TTHM formation using
a sufficient simulation length to overcome initial conditions and produce a
consistent, repeating pattern of 24-hour water age
IDSE Guidance Manual for the Final Stage 2 DBPR 6-2 January 2006
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Exhibit 6.2 Minimum Reporting Requirements for Modeling Study Plan
The following information must be provided in your Modeling Study Plan. You may use
the Modeling Study Plan Form (Form 4) found in this chapter or the IDSE tool to help you
prepare your submission.
1. Tabular or spreadsheet data demonstrating that your model meets the physical system
data requirements in Exhibit 6.1.
2. A description of all calibration activities undertaken (or to be undertaken). This must
include, if calibration is complete,
> A graph of predicted tank levels versus measured tank levels for the storage
facility with the highest residence time in each pressure zone.
> A time series graph of water age results for the storage facility with the highest
residence time in your system showing predictions for the entire EPS simulation
period (i.e. from time zero until the time it takes for the model to reach a
consistently repeating pattern of residence time).
3. Preliminary results of the modeling analysis showing showing 24-hour average water
age predictions throughout the distribution system.
4. Timing and number of samples planned for at least one period of TTFDVI and HAAS
monitoring at a number of locations no less than that required for your system under
standard monitoring during the month of high TTFDVI.
5. Description of how all requirements will be completed no later than 12 months after
your required plan submission date.
6. Distribution system schematic showing entry points and their sources, storage facilities,
and locations of all completed SSS monitoring and all subpartL compliance monitoring.
7. Population served and system type (subpart H or ground water).
Notes:
> You must respond to any state or EPA inquiries regarding your model and your
SSS plan submission.
> If you have already completed your required monitoring, it is highly recommended
that you submit your IDSE report at the same time as your study plan.
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For the purposes of the modeling SSS, water age is used as a surrogate for TTHM
concentration. Thus, the minimum requirements for the modeling SSS are focused only on the
hydraulic component of distribution system models. A well-calibrated water quality model may
provide a better understanding of the behavior of the distribution system, leading to superior
selections of Stage 2 DBPR compliance monitoring locations compared to hydraulic models
without water quality calibration. However, proper calibration of the water quality component
can be a difficult task and is typically done with much less accuracy than calibration of the
hydraulic component. In addition, the data needed to properly calibrate and verify the water
quality concentrations predicted by the model may exceed data collection requirements under the
IDSE standard monitoring option. If systems decide to use water quality modeling, they are
encouraged to provide information on the water quality calibration to EPA or the state in
addition to the required information for the underlying hydraulic components of the model.
A variety of public domain and commercial software packages are available for
distribution system modeling. Public domain software includes EPANET and PipelineNET,
which are both available for free download. EPANET is available from
www.epa.gov/ORD/NRMRL/wswrd/epanet.html and PipelineNET is available from
http://eh2o.saic.com/iwqss/. Systems should verify that the software used to model the
distribution system can provide the output required to demonstrate the model's calibration and
performance (Section 6.1).
If you have not already done so, you should complete the flowchart in Exhibit 2.3 of this
guidance manual. The flowchart will direct you to a 2-page Requirements Summary Sheet for
your schedule. You will also be directed to the System Specific Study Requirements -
Attachment sheet containing detailed requirements for Stage 2 compliance monitoring (e.g.,
number of samples and sampling frequency). You should keep these sheets handy as you work
through this chapter. It is important that consecutive and wholesale systems communicate
with each other throughout the IDSE process. If you are a consecutive or wholesale system,
refer to Appendix D for specific issues that you should consider.
If you plan to conduct an SSS using a model, you must submit a modeling study plan for
state or EPA review in accordance with the schedule on your requirements summary sheet. You
have the option of submitting the modeling study plan and IDSE report together (which must
include selection of Stage 2 DBPR compliance monitoring sites) by the study plan deadline if all
required elements have been completed. If you choose this option, you have no further
requirements under the IDSE unless you are contacted by EPA or your state. Below is a list of
conditions under which you should consider submitting the report at the same time as the plan,
and conditions under which you would want to submit your modeling study plan first, then your
report at the end of the IDSE monitoring period.
Option 1: Submitting a Completed Modeling Study Plan and IDSE Report at the Same Time
You should consider Option 1 if:
• You have completed calibration of your model, and
• You have completed one monitoring period of additional TTHM and HAAS
monitoring meeting the criteria in Section 6.3.
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You need to:
• Submit both the modeling study plan and the IDSE report by the deadline for the
modeling study plan that is provided on your requirements summary sheet.
Option 2: Submitting a Separate Modeling Study Plan and IDSE Report
You should consider Option 2 if:
• You have not completed calibration of your model, or
• You have not completed one monitoring period of additional TTHM and HAAS
monitoring meeting the criteria in Section 6.3.
You need to:
• Submit the modeling study plan by the deadline for the modeling study plan on your
requirements summary sheet.
Conduct additional monitoring and/or perform calibration by the date listed in your
requirements summary sheet.
Submit the IDSE report for a modeling SSS by the deadline in your requirements
summary sheet.
6.1 Minimum Model Requirements and Calibration
Exhibit 6.1 summarizes the minimum model requirements for the SSS. In general, a
system's distribution system hydraulic model should be more comprehensive for the purpose of
an SSS than models typically used for long-range capital improvement program analysis of
transmission capacity (e.g., master planning). A calibrated hydraulic model intended for detailed
distribution system design or operational studies is likely to be adequate. A well-calibrated
water quality model is also likely to be acceptable. In either case, the model must be an
extended period simulation (EPS) model. Also, the model must be calibrated for the peak
month for TTHM formation. Consequently, the model will need to incorporate operational
and demand conditions for the peak month for TTHM formation. See Section 6.3 for guidance
on selecting the peak month.
Distribution systems are always changing (e.g., population growth, new industrial users,
aging of mains), so it is important that the model reflect system conditions and demand at the
time of the SSS. If your model is not current, it must be updated and calibrated before it could
be considered adequate for the SSS. Your model must be calibrated for the current configuration
of the distribution system.
Sections 6.1.1 through 6.1.4 provide additional guidelines to help you determine if your
model meets the minimum requirements. Note that the guidelines in this section are not
comprehensive—every distribution system is unique. Systems should always use their best
professional judgment when determining model adequacy for the SSS. You should note that
EPA or your state can still require you to conduct standard monitoring even if you meet
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minimum requirements. AWWA Manual M32, Computer Modeling of Water Distribution
Systems, 2nd Edition, 2005, may be a useful reference that goes into greater detail on the
distribution system modeling presented in this chapter.
6.1.1 Physical System Data
Most distribution system models do not include every pipe in a distribution system.
Typically, small pipes near the periphery of the system and other pipes that affect relatively few
customers are excluded to a greater or lesser extent depending on the intended use of the model.
This process is called skeletonization. Models including only transmission networks (e.g. pipes
larger than 12 inches in diameter only) are highly skeletonized while models including many
smaller diameter distribution mains (e.g. 4 to 6 inches in diameter) are less skeletonized. In
general, water moves quickly through larger transmission piping and slower through the smaller
distribution mains. Therefore, the simulation of water age or water quality requires that the
smaller mains be included in the model to fully capture the residence time and potential water
quality degradation between the treatment plant and the customer. Increases in computing
capabilities are making it possible to include many more pipes in hydraulic models than was
previously feasible.
To be used for the purposes of conducting the SSS, the model should be relatively
detailed (less skeletonized) and include the majority of pipes in the distribution system.
Minimum requirements for physical system data are provided in Exhibit 6.1.
System inventory information can be used to determine the adequacy of the model,
including pipe information in GIS or on water atlas maps. Documentation of the ability of the
model to meet the minimum requirements must be submitted with the modeling study plan.
Most modeling software provides the ability to calculate and export data on the total length of
the pipes within the model. GIS, water system inventory data, or water atlas sheets can be used
to calculate the length of pipes that exist in the distribution system but are not included in the
model. Systems should use their best professional judgment in the estimation of the coverage of
the distribution system that is included in the model. An example of these calculations is
provided in Appendix F.
6.1.2 Demand Data
A key set of input data to a hydraulic model is the demand data used to simulate
consumption of water throughout the system. The demand data dictates the flow through each
pipe and therefore is an important part of the model. Water demand should be allocated among
the nodes in the model in a manner that reflects the actual spatial distribution of such demand
throughout the system, with a level of detail appropriate for the system size. A proper demand
allocation will help ensure that the model provides a realistic simulation of water flow
throughout the system.
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In general, it is desirable to have demand allocated to as many nodes as possible in the
model. The calculation of water age at nodes on dead end mains with zero demand is not
accurate because the water age will equal the simulation time at each time step, so often model
results will show the highest water age at dead ends. While this is a realistic representation of
the distribution system, you should take these results into consideration when selecting sampling
locations. Much of the modeling and GIS software available contains tools to assist with
demand allocation based on geocoding of customer accounts, processing of census population
data, or spatial analysis of land use patterns. Alternatively, it is possible to allocate customer
demands manually based on system knowledge of meter locations, meter reader routes, or zone
flow meters.
To ensure that your model is calibrated well for the period of high TTHM formation
potential, include all significant users in the system in your model. Many skeletonized models
will exclude dead ends in the system even though they may serve a subdivision or other area
with a sizable number of customers. Systems should make an effort to include dead end pipes
that serve significant populations to capture the full system demand as well as any potential
degradation of water quality within the dead end area. Exhibit 6.3a shows a typical subdivision
layout with dead ends that are not included in the model (more skeletonized) and Exhibit 6.3b
shows that model with all pipes included (less skeletonized).
Systems with rapidly changing populations and water usage should verify that the
demands in the hydraulic model reflect the distribution system conditions under which the SSS
will be evaluated. Particular attention should be paid to large users in the system, which are
often industrial or institutional and can have a significant impact on flows. Seasonal trends in
demand variation should also be considered so that the model reflects the correct water usage for
the month with the highest TTHM formation potential (see Section 6.3 for more information on
determining peak month for TTHM formation). For example, many commercial properties have
automatic irrigation systems that operate during summer months only and some systems may
have seasonal users such as campgrounds or swimming pools.
System water loss should also be reflected in the demands in the hydraulic model. Many
systems calculate a non-revenue water percentage based on the difference between their monthly
production records and customer billing data. This water loss should be included in the model.
Many systems apply a constant rate of water loss across their system by using a global demand
multiplier. However, if more detailed information on losses is available, such as measured losses
in a particular zone in the system, that data could be used to allocate the total water loss to
specific areas in the model.
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Exhibit 6.3a Sample Subdivision Layout in a Less Skeletonized Model
Exhibit 6.3b Sample Subdivision Layout in a More Skeletonized Model
Diurnal Demand Variation
The prediction of water age or water quality requires an extended period simulation
(EPS). To run a hydraulic model EPS, demand patterns showing the variation in usage over time
are required. Therefore, models must not only include realistic base demands but must also
reflect the variation in demand over time. For water age or water quality simulation in the
modeling SSS, a minimum of a 24-hour EPS is required and therefore this discussion will refer
to diurnal demand variations.
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Residential customers typically show a diurnal variation of water use with a peak in the
morning (before work) and in the evening (after work), with little use during the night. Large
users, such as industries, may use water on a different schedule than residential users. For
example, a factory running full production 24 hours per day will not decrease its water usage
during the night. In order to simulate realistic water movement throughout the distribution
system and calibrate your model, capture the different patterns of usage, particularly for large
users. Systems are encouraged to verify the diurnal water usage patterns for large users and to
include separate demand variation categories for these users if they differ from a typical
residential user.
Diurnal curves will also vary by season. For example, residential use will often increase
in the evening and night hours during the summer due to lawn watering. Other systems may
experience seasonal population shifts that will affect the demand patterns.
Demand patterns can be derived from a mass balance calculation using water production
and pumping records, tank levels, and other operational data. Most reference books on hydraulic
modeling include an explanation of diurnal demand variation calculations. The pattern is a
series of multipliers that represent the ratio of instantaneous demand to the average daily demand
at a given point in time. The average of all multipliers is equal to 1.0. Exhibit 6.4 shows an
example of a diurnal demand variation pattern.
The IDSE requires modeling of the peak month of TTFDVI formation and therefore
systems must ensure that their model adequately simulates demand variation during that month
for the purposes of the SSS. In addition to diurnal demand patterns, the total demand in the
model must match the typical demand for the peak month of TTHM formation. The base
demand in the model may need to be adjusted by using a global demand multiplier to better
represent the peak month of TTHM formation. See Section 6.3 for guidance on selecting the
peak month for TTHM formation.
6.1.3 Operational Controls
Another important feature of a good EPS model is the ability to simulate system
operation using controls. Controls are used within the model to turn on or off pumps, open or
close valves, and perform other operations to mimic the real-life operations that occur in a
system. The ability of the model to simulate the actual operation of the system requires the
specification of controls.
Hydraulic modeling software offers several options for controls. In general, controls are
either time-based or logical. Time-based controls perform a specific operation (e.g. turn on a
pump) at a specified time in the simulation. Logical controls perform a given operation based on
an evaluation of conditions in the system (e.g. turn on a pump when the tank is half empty). For
large systems, a series of conditions must often be met before a change in status of operation can
occur. To simulate these cases, complex logical controls can be created in the model.
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Exhibit 6.4 Example Diurnal Demand Variation Pattern
The simulation of water age and water quality throughout a distribution system is heavily
impacted by the modeled behavior at the storage facilities. The behavior of the storage facilities
is in turn greatly affected by the operational rules used to control levels and fill rates. Therefore
it is important that systems ensure that the controls used in the hydraulic model provide a
simulation of true system operation.
For the SSS using a distribution system model, you must simulate the conditions during
the period with the highest TTHM formation potential in your model.
6.1.4 Calibration
Once a base model for a distribution system has been developed, the model must be
calibrated to match the simulated system performance to actual operating conditions.
Calibration is generally an iterative process where model parameters are adjusted until
simulation results match field conditions. Systems must demonstrate that their model is either
calibrated using data collected during the peak month for TTHM formation or, if previously
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calibrated to a different time period, can satisfactorily simulate operation during the period with
the highest TTHM formation potential through model verification. Calibration of a model for
steady-state simulations only is not adequate for the modeling SSS. The model must be
calibrated in extended period simulation for at least a 24-hour period. Because storage facilities
have such a significant impact upon water age and reliability of water age predictions throughout
the distribution system, you must compare and evaluate the model predictions versus the actual
water levels of all storage facilities in the system to meet calibration requirements. However,
you are only required to submit the graph for the storage facility with the highest water age in
each pressure zone.
Calibration is never exact and there are no official calibration standards or guidelines in
the United States. There is general agreement in the modeling profession that the extent of
calibration should reflect the intended uses of the model. For example, a more rigorous model
calibration would be necessary when the model is used to make detailed design calculations
versus general master planning, where a larger margin of error in calibration may be acceptable.
Calibration performed several years ago for the purposes of general master planning is not
acceptable for the modeling SSS. For more information regarding the calibration of distribution
system hydraulic models, refer to Modeling Water Quality in Drinking Water Distribution
Systems (Clark and Grayman, 1998), Advanced Water Distribution Modeling and Management
(Walski et al., 2003), or other reference books.
Calibration Data Collection
Calibration data will vary by system depending on the type and number of facilities
involved. In general, calibration data will include:
• Flow and discharge pressure at each pump and/or pumping facility
• Water level in each storage facility (elevated and ground storage)
• Pressure data, either at facilities or other locations in the distribution system
• Flow tests at hydrants
• Friction factor (C-factor) tests
• System-wide demand and diurnal pattern information
Many systems collect operational data using supervisory control and data acquisition
(SCADA) systems, chart recorders, or other types of dataloggers. It is important to obtain
operational data over a 24-hour time period so that the EPS model can be calibrated for each
time step. This data must represent the actual operating conditions during the peak historical
month for TTHM formation.
Field studies may also be conducted to obtain flow test and friction factor test data. If
possible, such tests should coincide with operational data collection to provide a robust data set.
Reference books can provide instructions for conducting these tests.
If the model was previously calibrated to a time that does not coincide with the peak
month for TTHM formation (e.g., calibrated to an average day in March and the peak month for
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TTHM formation is August), additional data will need to be collected to verify the performance
of the model during the peak month for TTHM formation.
The operation of storage facilities in distribution systems has a significant impact on
water retention and potential for water quality degradation. Therefore, a simulation of the
behavior of all storage facilities during the peak month for TTHM formation is required as part
of the modeling SSS. The ability of the calibrated model to predict actual water levels in all
storage facilities must be verified.
In your modeling study plan you are required to describe your calibration process to
verify the adequacy of the model for the purposes of the SSS. If your model is not calibrated at
the time you submit your Modeling SSS Plan, you must describe the calibration activities that
are proposed to take place. You will then be required to submit your final calibration
documentation as part of your IDSE report. If you have already completed your calibration, you
must include the following in your modeling study plan:
• A model results graph of water level versus time for the storage facility with the
highest water age in each pressure zone of the system. If a pressure zone has no
storage facilities located within its boundaries, no graph is required for that zone.
The graph must include both simulated (model) and observed (actual) water levels
during the period of highest TTHM formation potential. The submitted graph should
show results for a minimum simulation length of 24 hours, with time increments no
greater than 1 hour. An example of an acceptable graph is shown in Exhibit 6.5.
• A time series graph of the residence time at the longest residence time storage facility
in the distribution system showing the predictions for the entire EPS simulation
period (i.e., from time zero until the time it takes for the model to reach a consistently
repeating pattern of residence time). An example of an acceptable graph is shown in
Exhibit 6.7. This graph will be produced as part of your water age modeling analysis.
Guidance on conducting the water age modeling analysis is given in Section 6.2.
If your model simulation results do not match the observed water level variations in the
storage facility but you feel that your model is sufficiently calibrated to be used in the SSS,
additional justification should be provided in your modeling study plan.
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Exhibit 6.5 Sample of an Acceptable Graph for Demonstration of Model
Calibration
Water Elevation for Tank 1
160.0
142.0-
140.0
o
Actual
Model
10 12 14 16 18 20 22 24 26 28 30 32 34 36 38
Time (hours)
40 42
6.2 Modeling Analysis
Using your calibrated hydraulic model of the distribution system, a water age simulation
must be run and analyzed to show 24 hour average residence time predictions throughout the
distribution system. Consecutive systems and systems with multiple sources with different water
quality should consider how the water age entering the distribution system and differing DBF
formation potential will influence model predictions and analysis. Appendix G discusses
approaches that can be used to analyze hydraulic models in these situations.
If your model calibration is not complete, a preliminary modeling analysis using the
existing model must be conducted and submitted with your modeling study plan. All required
calibration activities must then be completed within 12 months of your required plan
submission date. Documentation of your calibration along with the final modeling analysis
using the calibrated model must then be submitted as part of your IDSE Report. If your model is
calibrated, you should submit your final water age results in your modeling study plan (see
Section 6.4 for guidance).
The following sections provide guidance for the modeling analysis and the completion of
the modeling study plan.
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6.2.1 Water Age Modeling
For the modeling SSS, water age is being used as a surrogate for TTHM concentration.
A water age analysis can be conducted using a hydraulic model without additional input of water
quality data. This simulation option calculates the length of time that each parcel of water has
been in the system after leaving the source(s). The water age calculation is highly dependent on
the operational controls in the model (e.g., tank water levels used to control pump settings).
Therefore, the model must be set up to match the operating conditions during the peak month for
TTHM formation. This may require adjustments to model demands and controls.
Each water age simulation begins with an initial age of zero at all model nodes. The
water age increases as the simulation time increases until fresh water from the source arrives at a
given node. Nodes with zero or very small demand, especially at dead ends, will not receive
fresh water and therefore will not have an accurate simulation of water age. Similarly, the water
age for tanks will be equal to the simulation time until the entire volume of the tank has been
refreshed with water from the source. Depending on operating conditions in the simulation, this
may take as long as several weeks.
To overcome the effects of the initial conditions in a water age analysis, ensure that the
simulation runs for a sufficient length of time. The required length of the water age simulation
will vary depending on system characteristics, but can be approximated by the time it would take
to fully turn over all water in the worst case storage facility. The average water age for a given
storage facility is approximately equal to the inverse of the percent turnover. For example, a
tank with an average daily volume turnover of 33% has an average water age of 3 days (100/33 =
3); a tank with an average daily volume turnover of 25% has an average water age of 4 days
(100/25 = 4). However, hydraulic models have limited ability to account for tank mixing
characteristics. Storage facilities with poor mixing characteristics may have water that is
significantly older than the average water age.
An appropriate simulation time should generate a consistent, repeating pattern of water
age in the storage facility with the highest average water age. An example of a repeating pattern
is shown in the case study example in Section 6.2.2. Once the simulation has been completed,
only results from the stable, repeating portion of the simulation (e.g., the last 24 hours) should be
used in subsequent analyses. The intent of using a long simulation time for water age is not to
replicate multiple different days of operation of the system but only to overcome the effects of
initial water age settings (zero at all nodes) on the results.
Because of the length of the simulation for water age, controls should be checked to
ensure that they will perform properly throughout the simulation. Time-based controls that refer
to the simulation time (e.g. turn on Pump 1 at hour 11) will need to be adjusted to cover the full
length of the simulation. Many software packages have an option to use clock time rather than
simulation time for controls. The use of clock time (e.g. turn on Pump 1 at clock time 11) will
repeat the operation on each day of the simulation at the same time while the use of simulation
time will only perform the operation only once during the entire run. Logical controls (e.g. turn
on Pump 1 when Tank 1 level is 20 feet) will generally perform fine in a longer simulation, but
should be checked.
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Water age simulation is also sensitive to the time step used for calculations. In most
software packages this is referred to as the water quality time step. In general, the accuracy of
the simulation increases as the time step is decreased. However, the use of very small time steps
can result in longer processing time for larger models. A time step on the order of 1 to 5 minutes
is generally good for water age simulation, depending on the system configuration. Trial runs
with different time steps can be conducted to determine if the water age simulation is sensitive to
the time step selected.
Once the water age simulation is completed, the model results from the stable (repeating)
part of the simulation can be used to calculate an average water age at each node in the
distribution system. If your model calibration is not complete, the results of a modeling analysis
showing the preliminary (over 24 hours) water age results throughout the distribution system
must be submitted with your model study plan. In this case, the modeling analysis must be
verified after model calibration and the revised results must be submitted with your IDSE report.
If your model calibration is complete, you should submit your final water age results with the
model study plan (in lieu of the preliminary results). In either case, EPA recommends that you
submit water age results in tabular format to minimize security risks to your system.
6.2.2 Modeling Analysis Example
This case study is based on the NETS .NET example from the EPANET 2 modeling
package. This package can be downloaded from:
www.epa.gov/ORD/NRMRL/wswrd/epanet.html. The same analysis can be completed using
most modeling software packages, although the exact process may differ slightly.
The system, shown in Exhibit 6.6, contains two sources and three storage tanks. The
treatment plant at the LAKE source operates only from 6 AM to 8 PM while pumping from the
RIVER source is controlled by the level in Tank 1. The sources have similar DBF
concentrations and formation potentials and therefore can be considered to have the same effect
on the final concentrations observed in the distribution system. For a more complex example for
a system with different source characteristics, see Appendix G.
The model was already calibrated for summer conditions. The system data were then
modified to reflect the demands and operating conditions that were expected to occur during the
peak month for TTHM formation. This required the following change to the Simple Control rule
(time based) that was applied to the hours of operation for the pump at the LAKE source (Link
10):
Link 10 OPEN AT CLOCKTIME 6 AM
Link 10 CLOSED AT CLOCKTIME 8 PM
The calibration was verified for the peak month for TTHM formation by producing the
tank level graph depicted in Exhibit 6.5. The fit in this graph verifies that the previous
calibration is adequate to simulate operations during the peak month of TTHM formation.
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Exhibit 6.6 Schematic of the Case Study Distribution System
RTVER Source
LAKE Source
Water age simulations were then completed using increasing simulation durations (e.g.,
120 hours, 240 hours, etc.) until it was apparent that the water age in the storage tanks had
equilibrated. The default water quality time step of 5 minutes was used for each of these
simulations. The largest tank, Tank 3, was found to take the longest time to equilibrate. Exhibit
6.7 shows the time history of water age in this tank over an 840 hour simulation period.
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January 2006
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Exhibit 6.7 Water Age Graph for the Tank with the Highest Water Age
Water Age for Tank 3
190.0
180.0,
170.0,
160.0
150.0
140.0.
130.0,
120.0
e 110.0
1 100.0
& 90.0,
80.0.
70.0
60.0
50.0,
40.0,
30.0
20.0
10.0.
0.0,
400 450
Time (hours)
550
750
To make sure that this result was not sensitive to the water quality time step used, an
additional run was made using a reduced time step. Results from the smaller time step matched
those for the 5 minute time step.
Next, an analysis was conducted to find the average water age at each location in the
network. To do this, the following modifications were made to the network's data:
1. the water quality time step was kept at 5 minutes
2. the simulation duration was kept at 840 hours
3. the Report Start Time was set to 792 hours (i.e., 48 hours before the end of the
simulation)
4. the Statistic being reported by the program was set to AVERAGE (so that the average
age over the last 48 hours of the simulation would be reported).
The resulting average water age throughout the network is displayed graphically in
Exhibit 6.8. EPA suggests that you submit your 24 hour average residence time predictions in
tabular format without identifying all nodes on your distribution system schematic to avoid
creating a security risk for your system. An example of this is provided in Appendix F.
However, you will probably want to rely on graphic output (e.g., Exhibit 6.8) as you evaluate
your model to select SSS monitoring locations as described in Section 6.3.
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Exhibit 6.8 Locational Average Water Age Throughout the Study Area
RIVER Source
LAKE Source
243
6.3 Determining SSS Monitoring Requirements and Schedule
As part of the SSS using a distribution system hydraulic model, you must collect TTHM
and HAAS samples from the distribution system during the peak month for TTHM formation.
The number of monitoring locations must equal or exceed the required number of locations
required for IDSE standard monitoring. Stage 1 DBPR compliance monitoring locations can not
be selected as locations for your SSS monitoring. The types of locations (near entry point, high
TTHM, high HAAS, and average residence time) must also match the requirements for IDSE
standard monitoring. See Exhibit 6.9 to determine your monitoring location criteria according to
your system size and source water type.
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Exhibit 6.9 Requirements for Modeling SSS Sampling
Source
Water
Type
nibpart H
Ground
Water
Population Size Category1
<500 consecutive systems
<500 non-consecutive systems
500-3,300 consecutive systems
500-3,300 non-consecutive
systems
3,301-9,999
10,000-49,999
50,000-249,999
250,000-999,999
1,000,000-4,999,999
> 5.000.000
<500 consecutive systems
<500 non-consecutive systems
500-9,999
10,000-99,999
100,000-499,999
> 500.000
Distribution System Monitoring Locations2
Total
Number of
Samnles
2
2
2
2
4
8
16
24
32
40
2
2
2
6
8
12
Near
Entry
Points
1
1
1
o
J
4
6
8
1
1
1
2
Average
Residence
Time
1
2
4
6
8
10
1
1
2
High TTHM
Locations
1
1
1
1
2
o
J
5
8
10
12
1
1
1
2
o
J
4
High HAAS
Locations
1
1
1
2
4
6
8
10
1
1
2
o
J
4
1 Your monitoring requirements (locations and frequency) are based on the population served by your system.
2 A dual sample set (i.e., a TTHM and an HAAS sample) must be taken at each monitoring location during each monitoring period.
You should review all available compliance, study, or operational data to determine the
peak historical month for TTHM formation for your system. If you have monthly or quarterly
TTHM monitoring data, EPA recommends that you use this data as the basis for your historical
month. If you do not have monthly or quarterly data, EPA recommends that you select the
month with warmest water temperature as your peak month for TTHM formation. In some
cases, you may find data in addition to TTHM and temperature data helpful in selecting your
peak historical month. For example, some systems may regularly see an increase in total organic
carbon (TOC) levels in the spring or fall. If your TTHM monitoring does not capture a seasonal
increase in TOC, you may want to consider the month with highest TOC when selecting your
peak historical month.
You should include the basis for selecting your peak month for TTHM formation in your
Modeling Study Plan (see Section 6.4 for guidance on completing the modeling study plan).
Systems have different requirements for describing sampling plans in their modeling
study plans depending on whether they have completed calibration of their models.
• If you have not completed model calibration you must provide the number of samples
you plan to take and the planned sampling month in your modeling study plan.
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• If your calibration and modeling analysis are complete but sampling is not yet done,
you should indicate the proposed SSS sampling locations on your distribution
schematic in your modeling study plan.
• If you have completed calibration and sampling, you must indicate the sampled
locations on your distribution schematic in your study plan. You should strongly
consider submitting the IDSE report along with your modeling study plan.
Note that sampling must be completed by the deadline in your requirements summary sheet.
6.4 Preparing your Modeling Study Plan
After you have verified that your model meets the criteria in Section 6.1.1 through 6.1.4
and have determined the number and timing of your SSS samples, you are ready to prepare your
modeling study plan. Every system that conducts a modeling SSS must prepare and submit a
modeling study plan. You should submit your plan to the Information Processing and
Management Center (IPMC) for review by EPA or your state. See Section 1.4 of this guidance
manual for information on how to submit your plan to the IPMC.
EPA has developed a Modeling Study Plan Form (Form 4), presented in this section
and available electronically as part of the IDSE Tool. You are not required to use this form;
however, if you choose not to use it, refer to Exhibit 6.2 for a list of the minimum elements you
must include in your modeling study plan.
The IDSE Tool creates a custom form for your system and provides /
links to technical guidance from this manual. The tool is available on EPA's (
website at http://www.epa.gov/safewater/disinfection/stage2 . IDSE Tool
If your model is not calibrated but you plan to calibrate your model and complete the
modeling analysis as part of the SSS, you must submit your plan with a description of the
proposed calibration work to be done. You must also indicate how all requirements will be
completed within 12 months of your required plan submission date and provide a description of
how you intend to use your model to select monitoring locations. This will allow time to correct
deficiencies that might become apparent during the calibration process. A preliminary water age
analysis must also be conducted with your existing model and submitted as part of the plan (if
your model is calibrated, this should be your final water age analysis). If your model does not
meet the requirements in Exhibit 6.1 and you are unable to address all of the questions on Form
4, you should provide information about how you plan to address those issues during the SSS.
Your deadline for submitting your study plan can be found on your requirements
summary sheet in Chapter 2. If EPA or your state does not approve or request modifications to
your plan, or notify you that your plan is still under review within 12 months after the deadline
for plan submission, you may consider the plan approved. If you have not yet completed
calibration of your model, you must continue calibrating your model while your plan is
IDSE Guidance Manual for the Final Stage 2 DBPR 6^20 January 2006
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being reviewed to meet the requirement that all required calibration must be completed no
later than 12 months after your plan submission deadline.
Form 4 includes the following sections:
I. General Information
II. IDSE Requirements
III. Model Description
IV. Peak Month for TTHM Formation
V. Modeling Information
VI. Planned Stage 1 Compliance Monitoring Schedule
VII. Distribution System Schematic
VIII. Attachments
Sections of the form with an asterisk (*) are required by the Stage 2 DBPR. An example of a
completed modeling study plan using this form is provided in Appendix F.
I. General Information
LA. PWS information* - Important definitions for classifying your system are
provided in the definitions section at the beginning of this guidance manual. If
you have any questions on this section, contact EPA or your state.
PWSID - Enter your PWSID identification number here. This number is typically
assigned by your state.
PWS Name - Enter the name of your system here.
PWS Address - Enter the primary mailing address for your water system here.
Population Served - Enter the number of people served by your PWS.
Remember, this is your RETAIL population served, not including the population
served by consecutive systems that purchase water from you.
System Type - Put a check mark in the appropriate box to identify whether your
system is a CWS or a NTNCWS. Definitions for CWS and NTNCWS can be
found in the definitions section at the beginning of this guidance manual.
Source Water Type - Put a check mark in the appropriate box to identify whether
your system is a subpart H system or a ground water system. If you use any
surface water or GWUDI as a source, mark the subpart H box. Definitions for
subpart H system (including GWUDI) and ground water system can be found in
the definitions section at the beginning of this guidance manual.
Buying/Selling Relationships - Put a check mark in the appropriate box to identify
whether your system is a consecutive system, a wholesale system, or neither. If
IDSE Guidance Manual for the Final Stage 2 DBPR 6-21 January 2006
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you are both a consecutive and wholesale system (e.g., you buy and sell water),
check both boxes. Definitions for consecutive system and wholesale system can
be found in the definitions section at the beginning of this guidance manual and
in Appendix D.
IB. Date submitted* - Enter either the date that you are submitting the form
electronically, putting it in the mailbox, or dropping it off with an express
delivery service. Be sure to submit your modeling study plan before the deadline
found on your requirements summary sheet.
1C. PWS Operations - This section asks questions about your system to help inform
EPA and state personnel during the plan review process.
Residual Disinfectant Type - Put a check mark in the appropriate box to identify
the type of disinfectant you most often use to maintain a residual in your
distribution system (not necessarily the same disinfectant used for primary
disinfection at the treatment plant). If you use chloramine but switch to free
chlorine for a short time, you should still check chloramine only. If you use
chloramine and chlorine regularly in your system (e.g, 4 months of free chlorine
and 8 months of chloramines), check both chlorine and chloramine. If you
maintain your residual with a disinfectant other than chlorine or chloramines (e.g.,
chlorine dioxide), you should place a check next to the box marked "Other" and
enter the type of disinfectant you use in the blank next to "Other".
Number of Disinfected Sources - Enter the total number of sources that deliver
disinfected water to your distribution system. If you connect to a single
wholesale system at a number of locations in your distribution system, consider
this one source. Multiple wells that are disinfected at a common treatment plant
should also be considered one source. Do not count wells that are not disinfected
or are disinfected by UV only.
ID. Contact Person* - Enter the contact information of the person who is submitting
the form. This should be the person who will be available to answer questions
from EPA and/or the state reviewers.
II. IDSE Requirements*
II. A. SSS Monitoring - Copy the required number of samples from the table in Exhibit
6.9 that corresponds to your source type and the population served by your
system.
II.B. IDSE Schedule - Enter the schedule for your system based on the letter that you
received from EPA or your state. See Chapter 2 for more information on the
letter.
IDSE Guidance Manual for the Final Stage 2 DBPR 6-22 January 2006
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II.C. SSS Monitoring Frequency - You are required to monitor during the peak month
of TTHM formation. If you plan to conduct additional monitoring, describe it
here.
III. Model Description
III. A. Yes/No Questions* These questions refer to the physical data contained in your
model. Circle Y or N to indicate if your model complies with the requirements.
III.B. Model Development and Calibration* Provide a description of the history of
development and calibration of your model. Describe what the model has been
used to do, such as evaluating operational scenarios, capital improvements
planning, or water quality assessment. Discuss the types of decisions that were
based on results from the model. An example of this type of description is:
The model was developed in 2004 using GIS data for the water system. The
model was calibrated to maximum day flow conditions during July 2004. The
calibrated model has been used by our staff to identify improvements needed to
serve a new subdivision and to change our tank operating procedures to minimize
water age and maintain chlorine residual.
III.C. Demand Data For each question, provide a brief description of the data and
methods used to assign customer demands to the model.
HID. Calibration Activities* For each question, provide a brief description of the data
and methods used to calibrate your model. If your model is not currently
calibrated but you propose to calibrate the model as part of the SSS, provide a
description of the calibration effort you plan to undertake to ensure that
calibration is completed within 12 months of your required plan submission date.
If calibration is complete:
• Submit a graph that documents your model calibration by showing
simulated tank levels versus observed levels for the storage facility with
the highest water age in each pressure zone of your system (see Exhibit
6.5 for an example)*.
IV. Peak Month for TTHM Formation
IV. A. Peak Month for TTHM Formation* - Enter the month that you determined to be
your peak month for TTHM formation. See Section 6.3 for guidelines for
selecting your peak month for TTHM formation.
IV.B. Justification of Peak Month for TTHM Formation - Describe how you determined
in which month TTHM formation is highest in your system. You should describe
the types of data used to reach your conclusion.
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V. Modeling Information* - For each question, provide a brief description of the methods
used (or planned) to perform modeling for water age.
• If your model calibration has been completed, the modeling analysis should be
described in this section. Submit a graph of water age versus time for the entire
simulation duration for the tank with the highest overall water age in the system*
• If your model calibration is not complete, a preliminary modeling analysis must be
conducted with your existing model and the results must be submitted with your SSS
plan. In this case, the modeling analysis must be verified after model calibration and
revised results must be submitted with your IDSE report.
All systems must submit model output showing preliminary (or final) average water age
results over a 24-hour period as part of their modeling study plan. The 24-hour period
used for the average water age results table should represent a simulation time after the
model has achieved a stable, repeating water age pattern (e.g. the last 24 hours of the
simulation). EPA recommends that you submit this in tabular format to not pose a
security risk to your system.
VI. Planned Stage 1 DBPR Compliance Monitoring Schedule* - Enter the projected
sampling schedule for the number of Stage 1 DBPR monitoring periods in which you will
conduct Stage 1 DBPR monitoring during your system specific study. Verify that site
IDs in this table match the IDs on your distribution system schematic. If you are required
to monitor at more than 8 Stage 1 DBPR locations you will need to attach additional
sheets. You may also want to attach your Stage 1 DBPR monitoring plan.
VII. Distribution System Schematic* - Attach a distribution system schematic to your study
plan. The schematic must include the location of entry points and their sources, all
storage facilities, and locations of completed SSS monitoring (if applicable) and all
subpart L compliance monitoring. If you have not selected your SSS sample sites, you
must show these sites on a revised version of the schematic when you submit your IDSE
report.
Modeling study plans will not be considered confidential business information (CBI) and
are subject to the Freedom of Information Act (FOIA). Therefore, your distribution
system schematic should not contain information that poses a security risk to your
system, EPA suggests that you submit a Distribution system schematic with no
landmarks or addresses indicated. In addition to the required information indicated
above, you should also include pressure zone boundaries, locations of pump stations, and
the map scale.
Schematics should be as clear and easy to read as possible. They should typically be
submitted on a scale of between 1:4,000 and 1:8,000; however, larger-scale drawings are
acceptable as long as systems components can still be clearly shown. All sizes from 8!/2
inches x 11 inches to larger, plan-sized sheets are acceptable. If electronic versions are
submitted, use one of the following file types:
IDSE Guidance Manual for the Final Stage 2 DBPR 6-24 January 2006
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• Adobe PDF file (*.pdf)
• Microsoft Word (*.doc)
• WordPerfect (*.wpd)
• Image file (*.gif, *.bmp, *.jpg, *jpeg)
VIII. Attachments - Put a check mark in each of the boxes corresponding to any attachments
that you have included in your report.
Note that some of the attachments are required by the Stage 2 DBPR:
• Distribution System Schematic*
Tabular or spreadsheet documentation that your model meets minimum requirement*
• Graph of predicted tank levels vs. measured tank levels for the storage facility with
the highest residence time in each pressure zone* (Required if calibration is
complete)
• Time series graph of water age at the longest residence time storage facility in the
distribution system showing the predictions for the entire EPS simulation period*
(Required if calibration is complete)
• Model output showing preliminary 24 hour average water age predictions for all
nodes throughout the distribution system* (Required for all submissions. If your
model is calibrated, this should be your final water age predictions.)
If you submit your study plan electronically, you also have the option to submit
attachments in hard copy. Include a note in your electronic study plan explaining that
attachments are being submitted in hard copy, and mail the hard copy to the IPMC
mailing address in your Requirements Summary Sheet. The IPMC will match the hard
copy submission with your electronic submission when it is received.
Enter the total number of pages in your study plan (including attachments) in the blank at
the bottom of this section. This will allow EPA or your state to ensure that all pages
were received.
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Form 4: Modeling Study Plan
Page 1 of 6
I. GENERAL INFORMATION
A. PWS Information*
PWSID:
PWS Name:
PWS Address:
City:
B. Date Submitted*
State:
Zip:
Population Served:
System Type:
news
D NTNCWS
Source Water Type:
D Subpart H
n Ground
Buying / Selling Relationships:
D Consecutive System
D Wholesale System
D Neither
C. PWS Operations
Residual Disinfectant Type: n Chlorine n Chloramines n Other:_
Number of Disinfected Sources: Surface GWUDI Ground
Purchased
D. Contact Person*
Name:
Title:
Phone #:
E-mail:
Fax#:
II. IDSE REQUIREMENTS*
A. SSS Monitoring
B. Schedule
C. SSS Monitoring Frequency
Number of Samples
per Monitoring Period
Number of Monitoring
Periods
Total
n Schedule 1
n Schedule 2
n Schedule 3
n Schedule 4
n During peak month of TTHM formation
(1 monitoring period)
n Additional (describe)
IDSE Guidance Manual for the Final Stage 2 DBPR
6-27
January 2006
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Form 4: Modeling Study Plan
Page 2 of 6
III. MODEL DESCRIPTION
A. Answer Yes or No to the following questions*
(provide documentation in attached sheets)
1. Is your model an Extended Period Simulation model?
2. Does your model meet the minimum requirements described
below? Attach tables or spreadsheets to demonstrate that your
model meets these requirements.
Include 75% of pipe volume
Include 50% of pipe length
Include all pressure zones
Include all pipes 12" and larger
Include all 8" and larger pipes that connect pressure
zones, influence zones from different sources, storage
facilities, major demand areas, pumps, and control valves,
or are known or expected to be significant conveyors of
water
Include all 6" and larger pipes that connect remote areas
of a distribution system to the main portion of the system
Include all storage facilities with standard operations
represented in the model
Include all active pump stations with realistic controls
Include all active control valves
3. Is your model (or will it be) calibrated to simulate actual water
levels at all storage facilities and represent the current distribution
system configuration during the period of high TTHM formation?
4. If calibration is complete, does the model simulate 24 hour
variation in demand and show a consistently repeating 24 hour
pattern of residence time?
R Provide a history of your model development and calibration*,
dates (attach additional sheets if needed)
Y/N
Y/N
Y/N
Y/N
Y/N
Y/N
Y/N
Y/N
Y/N
Y/N
Y/N
Y/N
including
IDSE Guidance Manual for the Final Stage 2 DBPR 6-28 January 2006
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Form 4: Modeling Study Plan pages ore
III. MODEL DESCRIPTION (Continued)
C.
1.
2.
3.
4.
D.
1.
2.
3.
4.
How was demand data assigned to the model? (attach additional sheets if
needed)
What method was used to assign
demands throughout the system?
How did you estimate diurnal demand
variation? How did you determine
total system demand?
How many demand categories did
you use?
How did you address large water
users?
Describe all calibration activities* If your model is not currently calibrated,
describe how calibration will be completed within 12 months of the required
plan submission date using the questions 1-8 as guidance (attach additional
sheets if needed).
When was the model last calibrated?
What types of data were used in the
calibration?
When was the calibration data
collected?
What field tests have been performed
to collect calibration data?
IDSE Guidance Manual for the Final Stage 2 DBPR
6-29
January 2006
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Form 4: Modeling Study Plan page4of6
III. MODEL DESCRIPTION (Continued)
D.
5.
6.
7.
8.
(Continued)
How did you determine friction
factors (C-factors)?
Was the calibration completed for
the peak month for TTHM formation?
If not, was the model performance
verified for the peak month for TTHM
formation?
How well do actual tank levels
correlate with predicted tank levels
during the peak month for TTHM
formation?
See Attachments (Section VIM) for
additional submission
requirements.
If you are using a water quality
model, what parameters are
modeled? How was the model
calibrated?
IV. PEAK MONTH FOR TTHM FORMATION
A.
B.
Peak Month For TTHM Formation*
Justification of Peak Month for TTHM Formation
Describe how your system determined which month is the peak month for TTHM
formation (attach additional sheets if needed):
IDSE Guidance Manual for the Final Stage 2 DBPR
6-30
January 2006
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Form 4: Modeling Study Plan
Page 5 of 6
V. MODELING INFORMATION
How was the SSS modeling performed? (attach additional sheets as needed)
1.
2.
3.
4.
Was modeling done for the operating
conditions during the peak month for
TTHM formation?
How were operational controls
represented in the model?
How was water age simulated during
the peak month for TTHM formation
(time steps, length of simulation,
etc.)? If not yet done, indicate how
this will be addressed in the IDSE
report.
What are the average water age
results for your distribution system?
See Attachments (Section VIM) for
additional submission
requirements.
VI. PLANNED STAGE 1 DBPR COMPLIANCE MONITORING SCHEDULE*
Stage 1 DBPR
Monitoring Site
ID (from map) 1
Projected Sampling Date (date or week) 2
Period 1
Period 2
Period 3
Period 4
Verify that site IDs match IDs on your distribution system schematic (See Section VII of
this form). Attach additional copies if you are required to monitor at more than 8 Stage 1
DBPR sites.
2 period = monitoring period. Complete for the number of periods in which you must conduct
Stage 1 DBPR monitoring during IDSE monitoring. Can list exact date or week (e.g., week
of 7/9/07)
IDSE Guidance Manual for the Final Stage 2 DBPR
6-31
January 2006
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Form 4: Modeling Study Plan
VII. DISTRIBUTION SYSTEM SCHEMATIC*
ATTACH a schematic of your distribution system.
Distribution system schematics are not confidential and should not contain information that
poses a security risk to your system. EPA recommends that you submit the following:
Distribution system schematic with no landmarks or addresses indicated. Show
locations of sources, entry points, storage facilities, locations of completed monitoring,
and Stage 1 compliance monitoring locations (required). Also include pressure zone
boundaries and locations of pump stations. Provide map scale.
VIM. ATTACHMENTS
D Distribution System Schematic* (Section VII).
D Tabular or spreadsheet documentation that your model meets minimum
requirements* (Section III.A).
D Additional sheets for explaining your model (Section III.B).
D Graph of predicted tank levels vs. measured tank levels for the storage facility
with the highest residence time in each pressure zone* (Section III.D).
Required if calibration is complete.
D Time series graph of water age at the longest residence time storage facility in
the distribution system showing the predictions for the entire EPS simulation
period* (Section V). Required if calibration is complete.
D Additional sheets for explaining how you selected the peak historic month for
TTHM formation (Section IV).
D Model output showing preliminary 24 hour average water age predictions for all
nodes throughout the distribution system* (Required for all submissions. If your
model is calibrated, this should be your final water age predictions.) (Section V).
D Additional sheets describing the planned Stage 1 DBPR Compliance Monitoring
Schedule (Section VI).
Total Number of Pages in Your Plan
Note: All items marked with an asterisk (*) are required by the rule.
IDSE Guidance Manual for the Final Stage 2 DBPR 6-32 January 2006
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6.5 Selecting SSS Monitoring Sites and Conducting Monitoring
If EPA or your state does not approve or request modifications to your plan, or notify you
that your plan is still under review within 12 months after the deadline for plan submission, you
may consider the plan approved. Follow your approved study plan as you select SSS
monitoring sites and conduct monitoring. Once your calibration and modeling analysis is
completed (Sections 6.1.4 and 6.2) the next step is to select your SSS monitoring locations using
the model results and supplemental data. After the locations are selected, you will collect
samples during the peak month of TTHM formation and use this data, along with your model
results, to select your Stage 2 DBPR Sites.
6.5.1 Select SSS Monitoring Locations
As discussed in Section 6.3, systems should determine the number of SSS monitoring
locations for their system type and size based on the information provided in Exhibit 6.9.
You should keep track of your decision making process as you select SSS monitoring
locations and then select Stage 2 DBPR compliance monitoring locations because it will help
you justify your Stage 2 compliance monitoring site selection. When you prepare your IDSE
report, you will be required to provide justification for the selection of each Stage 2 DBPR
compliance monitoring site based on model results, monitoring results and additional data
analysis.
Depending on your system size and source water type, you will select up to four different
kinds of SSS monitoring sites: near entry point sites, average residence time sites, high TTHM
sites, and high HAAS sites. Guidance for near entry point sites is provided in Section 6.5.1.1.
Section 6.5.1.2 provides guidelines for using water age estimates from your model to select
average residence time and high TTHM sites. Section 6.5.1.3 provides additional considerations
for selecting high HAAS sites. Lastly, Section 6.5.1.4 provides a discussion of overarching
issues for consideration when you select your final SSS monitoring sites.
6.5.1.1 Identify Near Entry Point Monitoring Locations
Data from sites near the entry points to the distribution system represent minimum
residence time and can be used as a baseline for interpreting changes in water quality as water
travels through the system. EPA recommends that you use the following procedure to select
near entry point monitoring sites.
Step 1. Determine How Many Near Entry Point Sites You Need for SSS Monitoring
Determine how many near entry point monitoring sites you are required to have by
referring to Exhibit 6.9. Remember that SSS sampling requirements for models are based on the
population served by your individual system, not the largest population in your combined
distribution system.
IDSE Guidance Manual for the Final Stage 2 DBPR 6-33 January 2006
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Step 2. Determine How Many Entry Points are in Your System
For the purposes of the IDSE, entry points are the locations where disinfected water
enters your distribution system. Entry points can convey treated surface water, disinfected water
from wells, or purchased water from a wholesale system (as long as it has been disinfected).
Entry points generally include seasonal or intermittent connections. If a well is not disinfected
or is disinfected using ultraviolet light (UV) only, you should not consider it an entry point for
the purposes of the IDSE.
Step 3. Compare Results from Step 1 to Step 2
• If the number of near entry point sites required matches the number of entry points in
your system, select a sampling location near each entry point.
• If your system has FEWER entry points than required near entry point SSS
monitoring locations, you must replace the unassigned near entry point sites with
high TTHM and HAAS sites to maintain the required total number of SSS monitoring
sites for models. If you have an odd number of unused near entry point sites, select
an additional high TTHM site. See Chapter 7, Section 7.1.1 of this guidance manual
for an example of how systems used this procedure to replace near entry point sites
with high TTHM and high HAAS sites.
• If your system has MORE entry points than required near entry point SSS monitoring
locations, you must take samples near entry points to the distribution system having
the highest annual water flows. Section 7.1.1 of this guidance manual also includes
an example of selecting entry points with the highest annual water flows.
The Stage 2 DBPR does not define near entry point sites explicitly. EPA recommends
that you locate your near entry point sites between the entrance to the distribution system and
no later than first customer. If you are a consecutive system, a sample tap at the master meter
would be an appropriate near entry point site. If you do not have a sample tap at your master
meter, consider using the first customer as your near entry point site.
6.5.1.2 Use Your Model to Identify Average Residence Time and High TTHM Locations
Identifying Average Residence Time Sites
Average residence time is the average age of water delivered to customers in a
distribution system. Average residence time is not simply one-half the maximum residence time.
Ideally, it should be a flow-weighted or population-weighted estimate. The model results for
water age/DBP concentration can be used to determine the average residence time for your
system. One option for doing this is to list the water age/DBP concentration results in ranked
order for the entire system, as shown in Exhibit 6.10. This will help you to plot a histogram of
the results as shown in Exhibit 6.11. A histogram plot sorts the water age results into groups and
shows the percentage of nodes with water ages falling within the given range. From the
histogram it can be seen that the greatest number of nodes have water ages falling in the 20 hour
IDSE Guidance Manual for the Final Stage 2 DBPR 6-34 January 2006
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bin (bin range = 15 to 25 hours) and therefore the most frequently occurring water age is 20
hours. Using this method, 20 hours would be a reasonable average water age estimate for the
system.
Exhibit 6.10 Ranking of Water Age Results
Rank
1
2
3
4
25
26
27
47
48
49
71
72
73
95
96
97
Node ID
RIVER
LAKE
10
60
267
275
159
197
211
181
149
247
231
Tank 2
131
Tank3
Water Age (hours)
0
0
0.03
0.08
10.36
10.39
10.54
12.26
14.70
14.87
30.58
30.62
31.31
122.41
135.44
189.26
IDSE Guidance Manual for the Final Stage 2 DBPR
6-35
January 2006
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Exhibit 6.11 Histogram of Water Age Results
JU.UU
4U.UU
3J.UU
•8
O
ZJ.UU
O
ox zU.UU
j.UU
n nn
n
n „ n „
10
20 30 40 50 60 70
Average Water Age (hours)
90
100 More
Identify High TTHM Sites
It is not the intent of IDSE monitoring to identify sites with maximum daily or hourly
TTHM concentrations. Instead, you should choose candidate sites to represent areas of the
distribution system that you expect to have high average TTHM concentrations as compared to
other areas in the system. Increased water age typically leads to higher TTHM concentrations.
This principle is the basis of the guidance provided for selecting high TTHM sites using your
model. If you choose to consider additional factors in identifying high TTHM locations, Section
7.1.1 Step 4 describes typical water quality characteristics of high TTHM sites.
High TTHM sites can be identified by ranking the average water age results for nodes in
the model. For model results that directly simulate TTHM concentration, nodes can be ranked
by concentration to identify representative high locations. Areas in the distribution system
where water is mixed or blended from two different supply points can result in an area of
stagnant water, often with high water age and potential for high TTHM concentration. You
should select sites from your model with the highest water age or TTHM concentration.
Color coded maps such as those shown in the case study example in Section 6.2.2 can be
helpful in interpreting the model results to identify representative high TTHM locations. Many
software and GIS packages can be used to plot water age/TTHM concentration results along with
other water quality data to produce a graphical representation of the system.
IDSE Guidance Manual for the Final Stage 2 DBPR
6-36
January 2006
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You should also consider the following issues as you use your model to select high
TTHM locations:
• Water age at zero-demand nodes, particularly dead ends, may not be accurate.
The accuracy of water age estimates from a model generally decreases as the model
moves from large diameter mains to small diameter mains to subdivision piping and
dead-ends. This is due to the increasing uncertainty in water usage rates as the
system moves away from large, aggregate demands to smaller demands exerted by a
few customers or a single customer.
If the model is skeletonized, the model results for high water age/TTHM concentration
areas should be compared to maps of the actual distribution system piping and to actual customer
locations in those areas before sample locations are selected. You should try to assure that the
sample location is representative of the actual distribution system, not the model, in cases where
actual pipes may not all be included in the model in the high residence time areas.
6.5.1.3 Use Your Model and Other Data to Identify High HAAS Sites
As with high TTHM SSS monitoring sites, it is not the intent of IDSE monitoring to
identify sites with maximum daily or hourly HAAS concentrations. Instead, you should choose
high HAAS SSS monitoring sites to represent areas of the distribution system that you expect to
have high average HAAS concentrations as compared to other areas in the system. Higher
temperatures and increased residence time can lead to higher HAAS concentrations. However,
HAAS can biodegrade when disinfectant residual levels are low or non-existent. Therefore, a
high HAAS site will not necessarily be the site with the longest residence time. This principle is
the basis for the guidance provided for selecting candidate sites. If you choose to consider
additional factors in identifying high HAAS locations, Section 7.1.1 Step 5 describes typical
water quality characteristics of high HAAS sites. You may use the 3-step procedure below to
select high HAAS sites.
Step 1: Identify areas with high water age
Similar to high TTHM sites, the sites with high water age can be identified by ranking
the water age results for nodes in the model. For model results that simulate HAAS formation,
nodes can be ranked by concentration to identify representative high locations. Areas in the
distribution system where water is mixed or blended from two different supply points can result
in an area of stagnant water, often with high water age. You should select sites from your model
with the representative high water age or HAAS concentration that were not already selected as
high TTHM sites. The next paragraph will provide guidance on eliminating those locations
where biodegradation is likely.
Color coded maps such as those shown in the case study example in Section 6.2.2 can be
helpful in interpreting the model results to identify representative high HAAS locations. Many
software and GIS packages can be used to plot water age/HAAS concentration results along with
other water quality data to produce a graphical representation of the system.
IDSE Guidance Manual for the Final Stage 2 DBPR 6-3 7 January 2006
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Step 2: Eliminate sites where you suspect biodegradation
Analysis of disinfectant residual is important in determining potential for biodegradation
of HAAS. Sources of disinfectant residual data may include regular compliance monitoring sites
(e.g., SWTR or Stage 1 DBPR compliance monitoring sites), operational sample sites, or special
sites sampled in response to customer complaints.
Low disinfectant residuals relative to the system average generally indicate longer
residence times, and may correlate with higher HAAS concentrations. However, you should
eliminate any areas that regularly or typically in the summer months have free chlorine residuals
less than 0.2 mg/L or with chloramine residuals less than 0.5 mg/L. Sites with residuals below
these minimum levels are more likely to have significant biological activity and are therefore
more likely to have biodegradation of HAAS. Because disinfectant residuals typically decay
faster during the summer, a review of data from the summer months may be more useful in
identifying areas with consistently low residuals. HPC data may also be helpful in determining
whether biodegradation of HAAS is occurring in your system.
Step 3. Verify Sites Using a Map
If the model is skeletonized, the model results for high water age/DBP concentration
areas should be compared to maps of the actual distribution system piping and to actual customer
locations in those areas before sample locations are selected. Systems should try to assure that
the sample location is representative of the actual distribution system, not the model, in cases
where actual pipes may not all be included in the model in the high residence time areas.
6.5.1.4 Finalize SSS Monitoring Locations
To finalize the selection of SSS monitoring locations, you should plot all your sites on a
map and check that the sites meet all the criteria shown in the following steps. Color-coding and
other mapping options may be helpful in this process.
Step 1: Confirm that sites match expectations
The purpose of this step is to confirm that your sites cover key areas. The following
questions may be useful as you evaluate all SSS monitoring sites together on the map:
• Are high TTHM SSS monitoring sites located in the extremities of the distribution
system?
• Are high HAAS SSS monitoring sites located in the extremities where there are no
indications of biological activity or low disinfectant residual?
• Are high TTHM and HAAS SSS monitoring sites generally downstream of storage
facilities and booster disinfection stations?
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• Are there any other areas where you suspect water age is high that are not represented
with a high TTHM (and possibly high HAAS) SSS monitoring site?
Step 2. Consider geographic coverage and other factors to finalize site selection
The following issues should be considered in making final choices for SSS monitoring
sites:
Look for geographic representation. Select sites that are geographically diverse
from the other SSS monitoring sites and existing Stage 1 compliance monitoring
locations. EPA recommends that you locate at least one of the high TTHM SSS
monitoring sites in a remote area of the distribution system. If your distribution
system contains hydraulically isolated portions, you should represent as many of
these as possible with at least one SSS site. If you are only required to select one
high TTHM site, it is strongly recommended that you locate this site far away from
the treatment plant, near the last group of customers (but prior to the last fire
hydrant).
Look for hydraulic representation. Select SSS monitoring sites in hydraulically
different areas. Even if sites are geographically near each other, they may represent
different pressure zones. You should also select sites that represent mixing zones if
multiple sources with different water quality characteristics are used.
Use sites that "multi-task". Prioritize sites that meet the multiple siting criteria and
those identified based on more than one data source. For example, a candidate high
TTHM SSS monitoring site based on water age model results that has low
disinfectant residual historically, is near the edge of the distribution system and is
downstream of a tank would be an excellent SSS monitoring site.
Select sites that are projected to have high water age during the time of the day
when sampling is normally done.
Consider site access. Try to select SSS monitoring sites for which access will not be
an issue. Each site should remain accessible over the long term in case the site is
selected for Stage 2 DBPR compliance monitoring.
Select the best site in an area with several choices If you have more than enough
sites in a given area of the distribution system and no other data favors one over the
other, use historical TTHM or HAAS data (if available) to prioritize sites. For
example, if disinfectant residual data are the same for three sites over the same
periods, then the DBF data can be used to select a high TTHM/HAA5 SSS
monitoring site. Remember that you cannot use Stage 1 DBPR compliance
monitoring sites as SSS monitoring sites.
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6.5.2 Special Case: Using DBF Formation Modeling to Select Sites
DBF modeling results using chemical constituent reactions can also be used to assist in
selection of the SSS sampling locations. Systems should note that any DBF modeling would be
used in addition to completing the modeling SSS requirements for analysis and submittal of
water age results.
Most modeling software packages provide an option to model decay/formation of
chemical constituents including DBFs with user-specified kinetic coefficients. To calibrate a
model for a chemical constituent, field and laboratory tests are necessary to identify the kinetic
coefficients (e.g. THM formation rate coefficient and limiting concentration) and to verify the
results at different locations in the distribution system.
For a DBF formation simulation, the necessary input data includes:
• the DBF concentration leaving the source
• a first-order rate constant based on laboratory tests
• an ultimate formation potential (maximum concentration) of the DBF
As with the water age analysis, DBF modeling will begin each simulation with a zero
concentration at every node unless the user specifies an initial concentration. Historical data
could be used to determine initial concentrations throughout the distribution system. A long
simulation, similar to one required for water age, could also be used to ensure that the results are
not impacted by the initial concentration.
TTHM and HAAS are usually modeled separately in distribution systems because they
often have different formation rate constants and initial concentrations. HAAs may biodegrade
in the distribution system but there is currently no mechanism in the modeling software to
simulate both the formation and degradation simultaneously. In that case, HAA modeling may
be better suited to general predictions of maximum possible concentration in the absence of
degradation and may not calibrate well to actual field data.
6.5.3 Conducting Monitoring
This section presents sampling requirements and tips for sample collection for
conducting monitoring for your SSS model.
REMINDER: you must continue to collect samples and comply with the Stage 1 DBPR during
the IDSE. Results from SSS monitoring should not be used for making Stage 1 compliance
determinations.
You must collect a dual sample set (i.e., two samples) at each location during the peak
month for TTHM formation. One sample must be analyzed for TTHM and the other must be
analyzed for HAAS. Two samples are required because the analytical methods used for the two
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groups of contaminants require different sample preservation methods. You must use EPA-
approved methods for analysis of your TTHM and HAAS samples. More information on EPA-
approved methods can be found in Appendix C.
As you conduct SSS monitoring, you should keep in mind the following tips for sample
collection:
• Use appropriate sample bottles. You should use sample bottles that already contain
the appropriate dechlorinating agent and preservative for sample collection. You
should contact your lab for a recommended sampling and preservation protocol. A
typical sampling protocol can be found in Appendix C.
• Flush your sample tap. If you collect samples from a tap, you should open the cold
water tap and allow the line to flush until the water temperature has stabilized
(usually about 3-5 minutes). If you collect a sample at a hydrant or blow-off, the
flushing time only needs to be long enough to purge the connecting line to the main.
The purpose of this step is to ensure the sample does not represent stagnant water that
has been sitting for a long time in the water line between the street and the faucet.
The sample should represent the water flowing through the distribution system at the
chosen sampling point.
Collect cold water samples. If you collect indoor samples you should collect them
from a cold water line.
Collect additional water quality data. You may wish to collect additional water
quality data, such as disinfectant residual and temperature data, at the time of DBF
sample collection. This information can be helpful as you interpret monitoring
results (e.g., unusually low residual at a location could mean unusually high residence
time).
• Re-sample if a sample is lost or broken. If a sample bottle is lost or broken after
sample collection, you should re-sample as soon as possible after the loss occurs.
Only the lost sample needs to be recollected, not the entire sample set that was
collected together. Make sure to note the loss of sample and resample date as a
deviation in your IDSE report.
6.6 Selecting Stage 2 DBPR Compliance Monitoring Sites and Schedule
The purpose of the IDSE is to select Stage 2 DBPR compliance monitoring locations that
reflect sites with representative high TTHM and HAAS concentrations in the distribution system.
After completion of the modeling analysis, selection of SSS monitoring locations and sampling
during one monitoring period, the Stage 2 DBPR compliance monitoring sites must be selected
for use in future compliance monitoring.
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This section provides technical guidance for selecting Stage 2 Compliance Monitoring
Sites. Justification for each site is required to be submitted in the IDSE report for a modeling
SSS (See Section 6.7).
6.6.1 Analyzing Model Results at Monitoring Locations
To assist in the final selection of Stage 2 DBPR sampling locations, model results should
be examined for each SSS monitoring location and each Stage 2 DBPR compliance monitoring
location . It is recommended that you plot water age versus time for a minimum period of 24
hours at a time in the simulation when results have stabilized and are repeatable (e.g. last 24
hours of the simulation period) for each monitoring location. Note that you are required to
submit a graph of water age for each monitoring location that is selected as a Stage 2 DBPR
compliance monitoring site as part of the IDSE Report. As with all model analyses in the SSS,
the typical operations in the peak month for TTHM formation must be represented. An example
of an acceptable graph is given in Exhibit 6.12.
IMPORTANT NOTE: For security reasons, the graphs of water age for each selected Stage 2
compliance monitoring site should not be identified by site location number. A blind numbering
system should be used on each graph that you can discuss with EPA or your state if they contact
you with questions about your IDSE report.
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Exhibit 6.12 Example of Typical Water Age Variation over Time
Junction 547
800
700
6.6.2 Analyzing SSS Monitoring Results
You must calculate the locational running annual average (LRAA) for each SSS
monitoring site and Stage 1 DBPR compliance monitoring site in order to select Stage 2 DBPR
compliance monitoring sites. The LRAA for each SSS monitoring site is equivalent to the single
sample result taken during the peak month for TTHM formation (unless you conducted
additional sampling). The LRAA for each Stage 1 DBPR compliance monitoring site should be
the LRAA for the year in which you were required to complete SSS monitoring. It will be based
on either one or four data points depending on your Stage 1 compliance monitoring frequency.
You should consider using a spreadsheet to store your data and calculate your LRAAs.
6.6.3 Comparison of Modeling and Sampling Results
As part of the site selection process, you should compare modeling results to sampling
results. Because of the dynamic nature of distribution systems, it is not expected that every
sample will exactly match the model results. However, the sample data should generally
demonstrate that the SSS monitoring locations correspond to the areas of the distribution system
they were chosen to represent. Sampling results that do not fit with the predicted water age or
DBF modeling results should be noted. This check is intended to look for trends that indicate the
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selected sites may not be appropriate and determine whether additional model analysis should be
completed. For example, if many of the average residence time sites have TTHM concentrations
that are significantly greater than at the high TTHM sites, this may indicate a problem with the
model predictions. In this case it would be appropriate to revisit the model analysis to make sure
the completed sampling represents high TTHM and HAAS concentrations in the distribution
system.
Systems should explain any discrepancies between the modeling and sampling results
and describe any follow-up actions taken to investigate. In this case, systems should consider
the following scenarios when analyzing their modeling and sampling results:
The time of sample collection should be noted and compared to the water age graph
to determine if the sample time coincided with the time of maximum water age. DBF
concentrations can vary over time and while the average simulated concentration
might be considered high, the concentration at certain times of the day may be
relatively low.
• Operational events such as main breaks and flushing can change the typical flow
patterns in a system and thereby affect the DBF concentrations.
• Additional field data collected during the sampling period (e.g. chlorine residual,
heterotrophic plate count) may help to explain discrepancies between modeling and
sampling results.
Systems may choose to resample at the site(s).
• Verify that the model represents the current configuration of the distribution system.
Unexpected sampling results may indicate inconsistencies in the model.
6.6.4 Select Final Compliance Monitoring Sites
You must first use the site selection protocol in Exhibit 6.13 to identify Stage 2
compliance monitoring locations based on your LRAAs. The number of required Stage 2
compliance monitoring sites for your system can be found on page 2 of the System Specific
Study Requirements - Attachment sheet in Chapter 2. If you complete all steps in the protocol
and need additional compliance monitoring sites for the Stage 2 DBPR, repeat the protocol until
the required number of sites has been selected. If you arrive at Step 3 or Step 7 and have no
more Stage 1 DBPR sites from which to select, continue to the next step. You can also use
Worksheet 6.1 to help you organize your data.
You should compare Stage 2 sites selected using the protocol to model results for water
age. In general, TTHM and HAAS results and modeled water age are the most important factors
in site selection. You should consider both predicted average water age and the 24-hour
variation in water age. If you are choosing between two sites where one has large variations in
water age throughout the day and the other is relatively consistent, you should select the site with
consistent water age. Sites with discrepancies between model results and SSS monitoring results
can be selected as Stage 2 DBPR compliance monitoring sites if justification is provided in the
IDSE report.
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The Stage 2 DBPR allows you to consider additional factors when selecting Stage 2
compliance monitoring locations. As you work through the site selection protocol, you should
consider other factors that may lead you to select a site with a similar or slightly lower water age
and/or LRAA. For example:
The site provides more complete geographic coverage of the entire distribution
system
• The site allows you to maintain a historical record
• Sampling at that site provides the opportunity to collect other water quality or
operational data (e.g., chloramine systems may want to collect nitrate or nitrite data at
that site)
Your IDSE report must include the basis (analytical results and modeling) and
justification you used to select these Stage 2 DBPR compliance monitoring sites. This is
particularly important for sites where there was a discrepancy between the model and the
monitoring results. You should first explain why you selected the site for SSS monitoring, and
then why you selected the site for Stage 2 compliance monitoring using modeling results and
sample data. An example of how you might justify a site is given below.
This site has the highest water age of all nodes and had the highest TTHM levels of all
samples collected during our SSS monitoring. Therefore, it was selected as our first high
TTHM site.
It is possible that EPA or your state may not concur with your justification and may require you
to select different Stage 2 compliance monitoring sites.
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Worksheet 6.1 Stage 2 DBPR Site Selection Worksheet for a
Modeling SSS Page 1 of 1
Instructions:
1) Enter the number of required Stage 2 DBPR compliance monitoring sites based on your
System Specific Study Requirements -Attachment summary sheet from Chapter 2.
2) Enter the Site ID and LRAA for each SSS monitoring and Stage 1 compliance monitoring
location. You may want to sort your entries in order by TTHM LRAA or HAAS LRAA
values.
3) As you work through the site selection protocol in Exhibit 6.13, fill in the "Stage 2 Site
Type" column each time you select a site to indicate whether the site is a high TTHM, high
HAAS, Existing Stage 1 DBPR Compliance Monitoring Site, or selected using criteria other
than the protocol.
No. of Stage 2 DBPR Compliance Monitoring Sites Required
Highest TTHM Highest HAAS Existing Staae 1 TOTAL
Site ID
Example
LRAA
TTHM
(mg/L)
0.075
HAAS
(mg/L)
0.045
Stage 2 DBPR Site
Type*
Highest TTHM
* Enter Highest TTHM, Highest HAA5, or existing Stage 1 DBPR
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Exhibit 6.13 Protocol for Selecting Stage 2 DBPR (Subpart V) Compliance
Monitoring Sites
Steps1
[required by rule]
1
2
3
4
5
6
1
8
Select the location with the highest TTHM LRAA
Select the remaining location with the highest HAAS
LRAA
For subpart H systems: Select the remaining existing
Stage 1 DBPR average residence time compliance
monitoring location with the highest HAAS LRAA
For ground water systems: Select the remaining
existing Stage 1 DBPR maximum residence time
compliance monitoring location with the highest
HAAS LRAA
Skip this step if you have no more Stage 1 DBPR sites
Select the remaining location with the next highest
TTHM LRAA.
Select the remaining location with the next highest
TTHM LRAA
Select the remaining location with the next highest
HAAS LRAA
For subpart H systems: Select the remaining existing
Stage 1 DBPR average residence time compliance
monitoring location with the highest TTHM LRAA
For ground water systems: Select the remaining
existing Stage 1 DBPR maximum residence time
compliance monitoring location with the highest
TTHM LRAA
Skip this step if you have no more Stage 1 DBPR
Select the remaining location with the next highest
HAAS LRAA
Stage 2 Compliance Monitoring
Sites Selected 2
1st highest TTHM site
1st highest HA AS site
1st Stage 1 DBPR site
2nd highest TTHM site
3rd highest TTHM site
2nd highest HAAS site
2nd Stage 1 DBPR site
3rd highest HAAS site
If you need more Stage 2 DBPR compliance monitoring locations, Go back to Step 1 of this
protocol and repeat the steps until you have selected the required number of total sites.
1. All steps are based on your calculated LRAAs for your SSS monitoring sites and Stage 1 DBPR compliance
monitoring sites. This means that your existing Stage 1 DBPR sites can be selected in steps other than 3 or 7. Stop
when you reach your required number of Stage 2 DBPR compliance monitoring sites.
2. You cannot select the same site as a highest TTHM and a highest HAAS compliance monitoring site.
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6.6.5 Determining Your Stage 2 DBPR Compliance Monitoring Schedule
The first step in determining your Stage 2 DBPR compliance monitoring schedule is to
select your peak historical month. You should use the peak month for TTHM formation selected
in your SSS modeling plan unless new data suggest another month. Refer to Section 6.3 for
more information on determining peak historical month.
You must conduct Stage 2 DBPR compliance monitoring during the peak historical
month. If you are a ground water system that serves more than 9,999 people or you are a surface
water system that serves more than 499 people, you must also conduct Stage 2 compliance
sampling at 90 day intervals before and/or after the peak historical month.
The intent of the required time interval is to ensure that samples are representative of the
quality of water over an extended period and do not over-emphasize either high or low
concentrations of TTHM or HAAS that might occur seasonally. For example, a system on
quarterly monitoring could sample in the third full week of every third month. It is not
necessary to sample all sites on the same day.
6.7 Preparing the IDSE Report
Every system that conducts a modeling SSS must prepare and submit an IDSE Report. If
you will have completed all requirements of the IDSE by your plan submittal deadline, you may
submit completed forms or documentation for both the Modeling SSS Plan and IDSE Report for
a Modeling SSS at the same time. You should submit the report to the Information Processing
and Management Center (IPMC) for review by EPA or your state. See Section 1.4 of this
guidance manual for information on how to submit your report to the IPMC.
EPA has developed an IDSE Report for a Modeling SSS Form (Form 5), presented in
this section and available electronically as part of the IDSE Tool. You are not required to use
this form; however, if you choose not to use it, refer to Exhibit 6.14 for a list of the minimum
elements you must include in your IDSE report. If any information has changed since submittal
of your modeling study plan, revised information must be submitted with the report. A major
component of the modeling study plan is to report on the final calibration of the hydraulic model
and its suitability for use in the required modeling analysis. If you use Form 5 in this section,
your IDSE report will contain all required information about your model.
The IDSE Tool creates a custom form for your system and provides /
links to technical guidance from this manual. The tool is available on EPA's (
website at http://www.epa.gov/safewater/disinfection/stage2. IDSE
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Exhibit 6.14 Minimum Requirements for IDSE Report for a Modeling SSS
If you do not choose to use the IDSE Report for a Modeling SSS Form (Form 5), the
following information must be provided in your IDSE Report:
• Analytical results from Stage 1 DBPR compliance monitoring and SSS monitoring
in a tabular or spreadsheet format.
An updated system schematic, if changed from your modeling study plan
(Required if you did not indicate SSS monitoring locations in your study plan).
• Final information on model requirements, calibration, and modeling analysis, if
changed or new since submittal of your study plan, including tables and graphs.
A 24-hour time series graph of residence time for each Stage 2 DBPR compliance
monitoring location selected.
Selected Stage 2 DBPR compliance monitoring locations and timing, including the
basis (analytical results and modeling) and justification for selection of those
locations.
• Population served and system type (subpart H or ground water) if changed from
your modeling study plan.
An explanation of any deviations from your approved study plan.
Before you begin Stage 2 DBPR compliance monitoring, you will also be required to
prepare a Stage 2 DBPR compliance monitoring plan. In addition, if you are a subpart H system
serving >3,300 people, you must submit a copy of your Stage 2 compliance monitoring plan to
the state. If you include compliance calculation procedures in your IDSE report, the report can
meet the requirement of the plan, and you do not have to prepare or submit a separate plan. As a
guide for specifying your compliance calculation procedures, refer to the Stage 1 DBPR,
141.133(b), and your Stage 1 compliance monitoring plan. Check with your state, as they may
have different requirements under the Stage 2 DBPR. If you are a consecutive or wholesale
system, your state may choose to use its special primacy authority to modify your Stage 2
compliance monitoring requirements. In this case, you should check with the state to see if they
are going to use this authority. You should develop your IDSE report for the total number of
required Stage 2 compliance locations for your system.
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The IDSE Report for a Modeling SSS Form (Form 5) includes the following sections:
I. General Information
II. SSS and Stage 2 DBPR Requirements
III. Modeling Information
IV. SSS Monitoring Location Selection
V. SSS and Stage 1 DBPR Compliance Monitoring Results
VI. Selection of Stage 2 DBPR Compliance Monitoring Locations
VII. Justification of Stage 2 DBPR Compliance Monitoring Sites
VIII. Peak Historical Month
IX. Proposed Stage 2 DBPR Compliance Monitoring Dates
X. Distribution System Schematic
XI. Attachments
If you are submitting an SSS plan and IDSE report at the same time, you must submit the
portions listed in bold above. Sections of the form with an asterisk (*) are required by the Stage
2 DBPR. An example of a complete IDSE report for a modeling SSS using this form is in
Appendix F.
I. General Information
LA. PWS Information* - If nothing has changed since you completed your modeling
study plan, copy information from your plan into this section. If your system
characteristics have changed, see Section 6.4 of this chapter for guidance on
completing this section.
IB. Date Submitted* - Enter either the date that you are submitting the form
electronically, putting it in the mailbox, or dropping it off with an express
delivery service. Be sure to submit your IDSE report before the deadline found
on your requirements summary sheet.
1C. PWS Operations - This section asks questions about your system to help inform
EPA and state personnel during the plan review process. If nothing has changed
since you completed your modeling study, copy information from your plan into
this section. If your system characteristics have changed, see Section 6.4 of this
chapter for guidance on completing this section.
ID. Contact Person* - Enter the contact information of the person who is submitting
the report. This should be the person who will be available to answer questions
from EPA and/or state reviewers.
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II. SSS and Stage 2 DBPR Requirements*
II. A. Number of Required Stage 2 DBPR Compliance Monitoring Sites - Refer to the
System Specific Study Requirements - Attachment in Chapter 2. Copy the
numbers from the table that correspond to your source type and the population
served by your system.
II.B. IDSE Schedule - This should be the same schedule you entered for your
modeling study plan. See Section 6.3 of this chapter for guidance.
II.C. Stage 2 DBPR Compliance Monitoring Frequency - Refer to the System Specific
Study Requirements - Attachment in Chapter 2. From the "Stage 2 Compliance
Monitoring Requirements" table, locate the monitoring frequency that
corresponds to your source type and the population served by your system. Put a
check mark in the box corresponding to that monitoring frequency.
II.D. Number of Required SSS Samples - Enter the number of samples you were
required to collect during the peak month for TTHM formation.
III. Modeling Information
Systems with an approved model calibration as part of their modeling study plan do not
need to complete this section. If any of your information submitted as part of the
modeling study plan has changed, provide updated information in this section.
III. A. How was demand data assigned to the model? For each question, provide a brief
description of the data and methods used to assign customer demands to the
model.
III.B. Describe all calibration activities undertaken.* For each question, provide a brief
description of the data and methods used to calibrate your model.
If you did not complete calibration prior to your study plan submittal or if
your calibration has changed, submit a graph that documents your model
calibration by showing simulated tank levels versus observed levels for the
storage facility with the highest water age in each pressure zone of your system
(see Exhibit 6.5 for an example)*.
Systems with an approved model calibration as part of their modeling study plan
do not need to complete this section.
III.C. How was the SSS modeling performed?*
Systems with an approved model analysis as part of their modeling study plan do
not need to complete this section unless their information has changed.
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Systems who conducted their water age modeling analysis after submitting their
modeling study plan should answer all questions.
Submit model output showing final average water age results over a
24-hour period*. The 24-hour period used for the average water age
results table should represent a simulation time after the model has
achieved a stable, repeating water age pattern (e.g. the last 24 hours of the
simulation). EPA recommends that you submit this in tabular format to
not pose a security risk to your system.
Submit a graph of water age versus time for the entire simulation
duration for the tank with the highest overall water age in the
system*.
IV. SSS Monitoring Location Selection - Provide an explanation of the approach used to
analyze water age results to select SSS monitoring locations. Describe how sites were
ranked for water age (e.g. percentile, highest to lowest, etc.). Include any additional data
that was used to assist in the analysis, such as residual disinfectant concentration.
Describe practical considerations such as accessibility, coverage of geographic areas, or
coverage of hydraulic zones that factored into the decision.
V. SSS and Stage 1 DBPR Compliance Monitoring Results*
V. A. TTHM Results - Enter the TTHM results for each monitoring site for each
monitoring period in which you collected data. For each sample result, enter the
date on which sampling was conducted. You should enter all SSS monitoring
results as well as all Stage 1 DBPR compliance monitoring results collected
during the IDSE period. If you collected samples during a single monitoring
period, your LRAAs for those sites will be the same as the monitoring results.
For each site ID, identify the location type (High TTHM, High HAAS, Average,
Entry Point).
V.B. HAAS Results - Enter the HAAS results for each monitoring site for each
monitoring period in which you collected data. For each sample result, enter the
date on which sampling was conducted. You should enter all SSS monitoring
results as well as all Stage 1 DBPR compliance monitoring results collected
during the IDSE period. If you collected samples during a single monitoring
period, your LRAAs for those sites will be the same as the monitoring results.
For each site ID, identify the location type (High TTHM, High HAAS, Average,
Entry Point).
V.C. Where were your TTHM and HAAS samples analyzed? - Put a check mark in the
appropriate box to identify whether your system analyzed TTHM and HAAS
samples in an in-house laboratory or sent the samples to a certified laboratory for
analysis.
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If you analyzed your TTHM and HAAS samples in an in-house laboratory, check
the appropriate box to identify whether your laboratory is certified. If you sent
your TTHM and HAAS samples to a certified laboratory, enter the name of the
laboratory in the blank. If you used more than one laboratory (e.g., if you used
different laboratories for SSS samples and Stage 1 DBPR compliance samples),
list both laboratories, or check "in-house" and list the name of the laboratory if
applicable.
V.D. What method(s) was used to analyze your TTHM and HAAS samples? Put a
check mark in the appropriate box to indicate the analytical method used to
measure the TTHM and HAAS concentrations of your SSS and Stage 1 DBPR
compliance samples. If more than one method was used (e.g., if you used
different laboratories for SSS samples and Stage 1 DBPR compliance samples),
check more than one method. If you do not know what method was used, contact
your laboratory.
VI. Selection of Stage 2 DBPR Compliance Monitoring Locations - Describe the
comparison of sampling and modeling results. Provide a description of the comparison
between sampling and modeling results, including any follow-up investigations done to
resolve discrepancies. See Section 6.3.3 for more information.
• You must submit a graph of water age versus time for each site selected* You
should show the selected sites on the distribution system schematic and assign each
site a unique site ID (see Section XI). For security reasons, the graphs of water age
for each selected Stage 2 compliance monitoring site should not be identified by site
location number. A blind numbering system should be used on each graph, which
you can discuss with EPA or your state if they contact you with questions about your
IDSE report.
VII. Justification of Stage 2 DBPR Compliance Monitoring Sites* - Enter the site ID from
the distribution schematic and the site category (highest TTHM, highest HAAS, or Stage
1 DBPR). You must provide a justification for each site including the modeling and
sampling results that led you to select it. See Section 6.4.4 of this manual for guidance.
For example, a justification for a highest HAAS site might be:
High average water age, high HAAS results during monitoring, measurable residual in
historical TCR data, located in East Pressure Zone
Note that there is only space for 8 monitoring sites on this sheet. If you need more space,
attach additional sheets.
VIII. Peak Historical Month
VIII. A Peak Historical Month for TTHM and HAAS* - Enter the month that you
determined to be your peak historical month for TTHM and HAAS.
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VIII.B Is Your Peak Historical Month the Same as Your Peak Month for TTHM
Formation in Your Modeling Study Plan? - Put a check mark in the appropriate
box to identify whether your system is using the same peak. If your SSS
monitoring results or other factors prompted you to select a different peak month.
explain how you selected a new peak month. Note that the modeling SSS was
based on using the peak month for TTHM formation for the modeling analysis.
However, compliance with Stage 2 DBPR is based on the peak historical month
for TTHM and HAAS. You should use the same peak historical month that you
used for your SSS monitoring unless you have convincing data to do otherwise.
IX. Proposed Stage 2 DBPR Compliance Monitoring Schedule* - Enter the ID for each
Stage 2 DBPR compliance monitoring site in the table (these should match the ID's you
enter in Section VII and on your schematic). Enter your proposed sampling schedule for
the number of monitoring periods identified in Section II.C. The entry can be a specific
date or week and can be in a number of different formats. For example:
7/9/07
2nd week in Nov ' 07
Week of 7/9/07
Remember that at least one monitoring period must be during the peak historical month
identified in Section VIII. A. Note that there is only space for 8 monitoring sites on this
sheet. If you are a subpart H system serving more than 249,999 people you are required
to monitor at more than 8 sites. Therefore, you will need to attach additional sheets.
X. Distribution System Schematic* A distribution system schematic is required only if it
has changed from your approved modeling study plan. If it has changed, you must attach
a distribution system schematic If you did not show your SSS monitoring locations
on the distribution system schematic you submitted with your model study plan, you
must submit a revised distribution system schematic. See Section 6.4 of this manual
for guidance.
XI. Attachments - Put a check mark in each of the boxes corresponding to any attachments
that you have included in your report.
Note that there is only space for 8 monitoring sites in Section V and Section VII. If you
need additional space you can attach additional sheets.
Note that some of the attachments are required by the rule.
If you deviated from your approved study plan, you must attach an explanation of all
deviations.
If you submit your IDSE report electronically, you also have the option to submit
attachments in hard copy. Include a note in your electronic IDSE report explaining that
attachments are being submitted in hard copy, and mail the hard copy to the IPMC
IDSE Guidance Manual for the Final Stage 2 DBPR 6-54 January 2006
-------
mailing address in your Requirements Summary Sheet. The IPMC will match the hard
copy submission with your electronic submission when it is received.
If you are a subpart H system serving >3,300 people, you must submit a copy of your
Stage 2 compliance monitoring plan to the state. If you include compliance calculation
procedures in your IDSE report, the report can meet the requirement of the plan, and you
do not have to prepare or submit a separate plan. As a guide for specifying your
compliance calculation procedures, refer to the Stage 1 DBPR, 141.133(b), and your
Stage 1 compliance monitoring plan. Check with your state, as they may have different
requirements under the Stage 2 DBPR.
Enter the total number of pages in your IDSE report (including attachments) in the blank
at the bottom of this section. This will allow EPA or your state to ensure that all pages
were received.
IDSE Guidance Manual for the Final Stage 2 DBPR 6-55 January 2006
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IDSE Guidance Manual for the Final Stage 2 DBPR 6-56 January 2006
-------
Form 5: IDSE Report for a Modeling SSS pagei om
I. GENERAL INFORMATION
(Skip this section if you are submitting the plan and report at the same time)
A. PWS Information*
PWSID:
B. Date Submitted*
PWS Name:
PWS Address:
City:
State: Zip:
Population Served:
System Type: Source Wat<
D CWS D Subpart
D NTNCWS D Ground
C. PWS Operations
Residual Disinfectant Type:
Number of Disinfected Sources:
sr Type: Buying / Selling Relationships:
H D Consecutive System
D Wholesale System
D Neither
n Chlorine n Chloramines n Other:
Surface GWUDI Ground Purchased
D. Contact Person*
Name:
Title:
Phone Number:
Fax:
E-mail:
II. SSS AND STAGE 2 DBPR REQUIREMENTS*
A. Number of Required Stage 2 D
HiahestTTHM:
Hiahest HAAS:
B. IDSE Schedule
D Schedule 1
D Schedule 2
D Schedule 3
D Schedule 4
BPR Compliance Monitoring Sites TOTAL
Staae 1 DBPR:
C. Stage 2 DBPR Compliance Monitoring Frequency
n Once during peak historical month
n Every 90 days (4 monitoring periods)
D. Number of Required SSS Samples
TOTAL
IDSE Guidance Manual for the Final Stage 2 DBPR 6-5 7
January 2006
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Form 5: IDSE Report for a Modeling SSS page2ofn
III. MODELING INFORMATION
(Skip this section if you submitted a modeling study plan with an approved model calibration
and your information has not changed, or if you are submitting your plan and report at the
same time)
A.
1.
2.
3.
4.
B.
1.
2.
3.
4.
How was demand data assigned to the model? (attach additional sheets if
needed)
What method was used to assign
demands throughout the system?
How did you estimate diurnal
demand variation? How did you
determine total system demand?
How many demand categories did
you use?
How did you address large water
users?
Describe all calibration activities undertaken* (attach additional sheets if
needed)
When was the model last calibrated?
What types of data were used in the
calibration?
When was the calibration data
collected?
What field tests have been
performed to collect calibration data?
IDSE Guidance Manual for the Final Stage 2 DBPR 6-58
January 2006
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Form 5: IDSE Report for a Modeling SSS pagesom
III. MODELING INFORMATION (Continued)
5.
6.
7.
8.
How did you determine friction
factors (C-factors)?
Was the calibration completed for
the peak month for TTHM
formation? If not, was the model
performance verified for the peak
month for TTHM formation?
How well do actual tank levels
correlate with predicted tank levels
during the peak month for TTHM
formation?
Submit a graph of predicted tank
levels vs. measured tank levels
for the storage facility with the
highest water age in each
pressure zone.*
If you are using a water quality
model, what parameters are
modeled? How was the model
calibrated?
IDSE Guidance Manual for the Final Stage 2 DBPR 6-59
January 2006
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Form 5: IDSE Report for a Modeling SSS page4ofn
III. MODELING INFORMATION (Continued)
C. How was the SSS modeling performed?* (attach additional sheets as needed)
1.
2.
3.
4.
Was modeling done for the
operating conditions during the
peak month for TTHM formation*?
How were operational controls
represented in the model?
How was water age simulated
during the peak month for TTHM
formation (time steps, length of
simulation, etc.)?
What are the average water age
results for your distribution
system?
Submit final model output
showing 24-hour average
residence time throughout the
distribution system*.
Submit graph of water age at
the longest residence time
storage facility in the
distribution system showing
the predictions for the entire
EPS simulation period*.
IDSE Guidance Manual for the Final Stage 2 DBPR 6-60
January 2006
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Form 5: IDSE Report for a Modeling SSS pagesom
IV. SSS MONITORING LOCATION SELECTION
How
1.
2.
3.
4.
5.
were the SSS monitoring locations selected? (attach additional sheets as needed)
What model results were used as
the basis for selection?
What criteria were used in selecting
average residence time, high
TTHM, and high HAAS sites?
What additional data was used in
the analysis, and how was it used?
How did you look at practical
considerations like accessibility of
sampling locations?
How did you verify that your
selected sampling locations
corresponded to the selected node
in your model?
IDSE Guidance Manual for the Final Stage 2 DBPR 6-61
January 2006
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Form 5: IDSE Report for a Modeling SSS pageeom
V. SSS AND STAGE 1 DBPR COMPLIANCE MONITORING RESULTS*
A. T
THM Results
Site ID &
Category
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
TTHM (mg/L)
LRAA
Attach additional sheets as needed for SSS and Stage 1 DBPR results.
IDSE Guidance Manual for the Final Stage 2 DBPR 6-62
January 2006
-------
Form 5: IDSE Report for a Modeling SSS page7ofn
V. SSS AND STAGE 1 DBPR COMPLIANCE MONITORING RESULTS* (Continued)
B. H
AA5 Results
Site ID &
Category
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
HAAS (mg/L)
LRAA
Attach additional sheets as needed for SSS and Stage 1 DBPR results.
IDSE Guidance Manual for the Final Stage 2 DBPR 6-63
January 2006
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Form 5: IDSE Report for a Modeling SSS
Page 8 of 11
V. SSS AND STAGE 1 DBPR COMPLIANCE MONITORING RESULTS* (Continued)
C.
Where were your TTHM and HAAS samples analyzed?
n In-House
Is your in-house laboratory certified? n Yes
D Certified Laboratory
Name of certified laboratory:
n No
D. What method(s) was used to analyze your TTHM and HAAS samples?
TTHM HAAS
D EPA 502.2 D EPA 552.1 D EPA 552.2
D EPA 524.2 D EPA 552.3 D SM 6251 B
D EPA 551.1
VI. SELECTION OF STAGE 2 DBPR COMPLIANCE MONITORING LOCATIONS
Describe the comparison of sampling and modeling results (attach additional sheets as
needed):
1.
2.
3.
4.
How well did the sampling results
correspond to the modeling
results?
For samples that did not match
well with model results, what
follow-up investigations were
performed?
Were additional samples
collected? (Include data on table
in Section IV)
Submit a graph of water age
versus time for each selected
sampling location*.
IDSE Guidance Manual for the Final Stage 2 DBPR 6-64
January 2006
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Form 5: IDSE Report for a Modeling SSS page9ofn
VII. JUSTIFICATION OF STAGE 2 DBPR COMPLIANCE MONITORING SITES*
Stage 2
Compliance
Monitoring
Site ID
Site Type
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
Justification
Attach additional copies of this sheet if you need more room.
IDSE Guidance Manual for the Final Stage 2 DBPR 6-65
January 2006
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Form 5: IDSE Report for a Modeling SSS
Page 10 of 11
VIM. PEAK HISTORICAL MONTH
A.
B.
Peak Historical Month*
Is Your Peak Historical Month the Same as your Peak Month in Your
Modeling Study Plan?
D Yes D No
If no, explain how you selected your new peak historical month
(attach additional sheets if needed):
IX. PROPOSED STAGE 2 COMPLIANCE MONITORING SCHEDULE*
Stage 2
Compliance
Monitoring
Site ID
Projected Sampling Date (date or week)1
period 1
period 2
period 3
period 4
1 period = monitoring period. Complete for the number of monitoring periods from
Section II. C.
Attach additional copies of this sheet if you need more room.
IDSE Guidance Manual for the Final Stage 2 DBPR 6-66
January 2006
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Form 5: IDSE Report for a Modeling SSS
X. DISTRIBUTION SYSTEM SCHEMATIC*
(Skip this section if you submitted a modeling study plan and your distribution system
schematic was complete and has not changed from your approved modeling study plan, or if
you are submitting the plan and report at the same time)
ATTACH a schematic of your distribution system. If your schematic has changed or if
you did not show your SSS monitoring locations on the distribution system schematic
you submitted with your model study plan (Form 4), you must submit a revised
distribution system schematic.
XI. ATTACHMENTS
D Tabular or spreadsheet documentation that your model meets minimum calibration
requirements if updated since approved modeling study plan* (Section III).
D Additional sheets for explaining model information/results, including required graphs if
not submitted as part of an approved modeling study plan* (Section III).
D Additional sheets for sampling results, if needed (Section V).
D Additional sheets for selection of Stage 2 DBPR compliance monitoring sites
(Section VI).
D Graph of water age versus time for all Stage 2 DBPR sites selected* (Section VI).
D Additional sheets for justification of Stage 2 DBPR Compliance Monitoring Sites, if
needed (Section VII). REQUIRED if you are a subpart H system serving more
than 249,999 people.
D Additional sheets for explaining how you selected the peak historical month (Section
VIII).
D Additional sheets for proposed compliance monitoring schedule (Section IX).
REQUIRED if you are a subpart H system serving more than 249,999 people.
D Explanation of deviations from approved study plan.
D Distribution system schematic* (Section X). REQUIRED if it has changed from
your approved model study plan or if monitoring locations were not shown.
D Compliance calculation procedures (for Stage 2 Compliance Monitoring Plan).
Total Number of Pages in Your Report:
Note: All items marked with an asterisk (*) are required by the rule.
IDSE Guidance Manual for the Final Stage 2 DBPR 6-67 January 2006
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IDSE Guidance Manual for the Final Stage 2 DBPR 6-68 January 2006
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6.8 Recordkeeping
The IDSE report for a modeling SSS must be kept on file for
10 years after the date it is submitted. If EPA or your state modifies
the recommendations made in your report or approves alternative
Stage 2 DBPR compliance monitoring locations, you must also keep
a copy of EPA or your state's notification on file for 10 years after
the date of the notification. You must make your IDSE report and
any notification available for review by your state or the public.
The modeling study plan, including any modifications by
EPA or your state, must also be kept on file for as long as you are
required to retain your IDSE report for a modeling SSS. You must
make the plan and any modifications available for review by your state or the public
6.9 Next Steps: Preparing the Stage 2 DBPR Compliance Monitoring Plan
As the final step before you can begin compliance monitoring for the Stage 2 DBPR, you
must develop and implement a Stage 2 DBPR monitoring plan by the deadline provided in
your requirements summary sheet. The plan will be similar to your Stage 1 DBPR monitoring
plan in that it will identify how you intend to sample for compliance with Stage 2. You must
keep your plan on file for state and public review. If you are a subpart H system serving >
3,300 people, you must submit your plan to EPA or your state prior to when you are required to
start monitoring.
Exhibit 6.15 contains the minimum requirements for what must be included in your
Stage 2 DBPR compliance monitoring plan. Because compliance monitoring plans are not
addressed as part of the IDSE provisions of the Stage 2 DBPR, EPA has not included detailed
guidance for developing Stage 2 compliance monitoring plans in this guidance manual.
EPA plans to develop other manuals and training that address the compliance monitoring
provisions of the Stage 2 DBPR.
See EPA's website http://www.epa.gov/safewater/disinfection/stage2 for a up-to-date
inventory of Stage 2 DBPR guidance manuals and training materials, or call the Safe Drinking
Water Hotline at 1-800-426-4791.
IDSE Guidance Manual for the Final Stage 2 DBPR 6-69
January 2006
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Exhibit 6.15 Required Contents of Stage 2 DBPR Compliance Monitoring Plans
All Systems
Additional Requirements for Consecutive and
Wholesale Systems l
Monitoring locations
Monitoring dates
Compliance calculation
procedures
If your state has used its special primacy
authority to modify your monitoring
requirements, you must include monitoring plans
for other systems in your combined distribution
system
1. See Appendix D of this manual for guidance specifically for consecutive and wholesale systems
References
R.M. Clark and W.M. Grayman. 1998. "Modeling Water Quality in Drinking Water Systems", AWWA, Denver, CO
T.M. Walski, D.V. Chase, D.A. Savic, W. Grayman, S. Beckwith, E. Koelle. 2003. "Advanced Water Distribution
Modeling and Management", Haestad Methods, Waterbury CT: Haestad Press.
IDSE Guidance Manual for the Final Stage 2 DBPR 6- 70
January 2006
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7.0 Standard Monitoring
This chapter covers:
7.1 Selecting Standard Monitoring Sites and Preparing Your Standard
Monitoring Plan
fa Form 6: Standard Monitoring Plan
7.2 Conducting Standard Monitoring
7.3 Selecting Stage 2 DBPR Compliance Monitoring Sites and Preparing the
IDSE Report
fa Form 7: IDSE Report for Standard Monitoring
7.4 Recordkeeping
7.5 Next Steps: Preparing the Stage 2 DBPR Compliance Monitoring Plan
Standard monitoring is one year of increased distribution system monitoring to find
locations with high total trihalomethane (TTHM) and haloacetic acid-five (HAAS)
concentrations. Results from standard monitoring will be used in conjunction with results from
Stage 1 compliance monitoring to select Stage 2 compliance monitoring locations. Any system
can conduct standard monitoring to meet the IDSE requirements of the Stage 2 Disinfectants and
Disinfection Byproducts Rule (DBPR).
If you have not already done so, you should complete the flowchart in Exhibit 2.3 of this
guidance manual. Depending on your system size and available data, you may have another
option for complying with IDSE requirements. The flowchart will help you select the most
appropriate IDSE option for your system and will direct you to a 2-page Requirements
Summary Sheet for your schedule. You will also be directed to the Standard Monitoring
Requirements - Attachment sheet containing detailed requirements for standard monitoring and
Stage 2 compliance monitoring (e.g., number of samples and sampling frequency). You should
keep these sheets handy as you work through this chapter.
This chapter provides guidelines on how to select standard monitoring sites, prepare a
standard monitoring plan, conduct standard monitoring, select Stage 2 DBPR compliance
monitoring sites, and prepare the IDSE report. Appendices H and I support this chapter by
providing example standard monitoring plans and reports. Guidance for standard monitoring is
also available in the EPA manual, Initial Distribution System Evaluation Guide for Systems
Serving < 10,000 People. This guide is specifically targeted to small systems and contains an
example monitoring plan and report for a small surface water system.
It is important that consecutive and wholesale systems communicate with each other
throughout the IDSE process. If you are a consecutive or wholesale system, refer to Appendix
D for specific issues that you should consider.
IDSE Guidance Manual for the Final Stage 2 DBPR ~January 2006
-------
IMPORTANT: Results from IDSE standard monitoring should not be used to determine
compliance with maximum contaminant levels (MCLs) of the Stage 1 DBPR. Results must,
however, be included in the range of levels that you report in your Consumer Confidence Report.
During the entire IDSE period, you must continue to monitor according to your Stage 1 DBPR
monitoring plan and comply with Stage 1 DBPR MCLs at your Stage 1 sites.
7.1 Selecting Standard Monitoring Sites and Preparing Your Standard
Monitoring Plan
Every system that conducts IDSE standard monitoring must prepare and submit a
Standard Monitoring Plan. You should submit the plan to the Information Processing and
Management Center (IPMC) for review by EPA or your state. See Section 1.4 of this guidance
manual for information on how to submit your plan to the IPMC.
This section contains EPA's recommended technical approach for selecting standard
monitoring sites. It also contains the recommended approach for selecting the peak historical
month and scheduling standard monitoring. Lastly, this section provides guidance on
completing the IDSE standard monitoring plan.
EPA has developed a Standard Monitoring Plan Form (Form 6),
presented in Section 7.1.3 and available electronically as part of the IDSE Tool. i,
You are not required to use this form; however, if you choose not to use it, refer to f
Exhibit 7.1 for a list of the minimum elements you must include in your standard
monitoring plan. The IDSE Tool is available on EPA's website at IDSE Tool
http://www.epa.gov/safewater/disinfection/stage2.
Exhibit 7.1 Required Elements of Your Standard Monitoring Plan
The population served by your system
Your system type (subpart H or ground water)
1 A distribution system schematic showing
- entry points
- sources
- storage facilities
- locations and dates of all projected standard monitoring and Stage 1 DBPR
compliance samples
1 Peak historical month
Justification of standard monitoring site selection and a summary of data you
relied on to justify standard monitoring site selection
IDSE Guidance Manual for the Final Stage 2 DBPR 7-2 January 2006
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7.1.1 Recommended Approach for Selecting Standard Monitoring Sites
You are required to select up to four types of standard monitoring sites for the IDSE:
• near entry point
• average residence time
• high TTHM
• high HAAS
Before you continue reading this chapter of the manual, you should use the IDSE Standard
Monitoring Table in the Standard Monitoring Requirements - Attachment sheet from Chapter 2
to determine how many of each type of site is required for your system. Remember that IDSE
standard monitoring requirements (i.e., the number of monitoring sites and sampling frequency)
are based on the population served by your individual system, not the largest population in your
combined distribution system.
EPA's recommended 8-Step technical approach for selecting standard monitoring sites
is summarized below and depicted graphically in Exhibit 7.2. The remainder of this section
contains detailed guidance for each of these eight steps.
1. Gather water quality data and system operating information including Stage 1
and historic DBF data from the last several years. You may also want to use advanced
tools (e.g., hydraulic model, tracer study data) if available.
2. Use data sources and tools to select near entry point sites.
3. Use data sources and tools to select candidate average residence time sites. Try to
identify at least twice as many candidate sites as are required for standard monitoring.
4. Use data sources and tools to select candidate high TTHM sites. Try to identify at
least twice as many candidate sites as are required for standard monitoring.
5. Use data sources and tools to select candidate high HAAS sites. Try to identify at
least twice as many candidate sites as are required for standard monitoring.
6. Plot the near entry point sites and all candidate sites on a map of your
distribution system. You should include your Stage 1 DBPR compliance
monitoring sites on the map so that you do not inadvertently select them as standard
monitoring sites. You may want to color-code candidate sites (e.g., by type of site or
data source).
7. Consider geographic coverage and other factors to select standard monitoring sites
from candidate sites.
8. Write your justifications for site selection and summary of data that you relied on
to select standard monitoring sites.
IDSE Guidance Manual for the Final Stage 2 DBPR ~3 January 2006
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Exhibit 7.2 Recommended Approach to Selecting Standard Monitoring Sites
Step 1: Gather Data
and Tools
-Water quality data
-System information
-Advanced tools
1
A
Step 2: Select
Near Entry
Point Sites
J
^\
1
Step 3: Select
Candidate Sites
for
Average Residence
. Time ,
>k
1
/" N
Step 4: Select
Candidate Sites
for
High TTHM
V J
*f
1
s ~\
Step 5: Select
Candidate Sites
for
High HAAS
V J
^^
Step 6: Plot
Candidate Sites
Plot near entry point
candidate sites.
Also plot Stage 1 compliance
monitoring sites. J
" + ^
Step 7: Select
Standard
Monitoring Sites
Step 8: Write
justification and
summary of data
Remember that Stage 1 DBPR compliance monitoring sites cannot be used as standard
monitoring sites.
IDSE Guidance Manual for the Final Stage 2 DBPR 7-4
January 2006
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Step 1: Gather Data and Tools
There are many kinds of data and tools that can be useful in selecting standard
monitoring sites. Exhibit 7.3 shows the types of information typically available to water systems
and for which types of sites they should be used.
One of the most important tools you can use to select standard monitoring sites is an up-
to-date, detailed map of your distribution system. When you submit your standard monitoring
plan, you are required to include a schematic of your distribution system showing all entry
points, sources and storage facilities. Other useful map features include the layout of pipes,
locations pump stations, pressure zone boundaries, locations of large users, and population
density information. For security reasons, EPA recommends that you remove any information
that could pose a security risk from your standard monitoring plan submittal. You may wish to
use a separate, working version of your distribution system map for selecting sites, then transfer
your information to a less detailed map for your standard monitoring plan submittal.
It is important that you consider available water quality data from your distribution
system when selecting standard monitoring sites. In general, your water quality data should be
less than 10 years old and should represent current system configurations to the extent possible.
Most systems have collected disinfectant residual data from their distribution system, and this
data can be very useful for selecting standard monitoring locations. EPA has provided additional
guidelines for evaluating disinfectant residual data in Step 3.
Systems with multiple entry points that have different source water characteristics may
find source water data quite useful for selecting standard monitoring sites. For instance, if a
system has one surface water source and one ground water source, entry point sampling may
indicate the surface water source produces much higher TTHM and HAAS levels than the
ground water source. Therefore, the water system may use this information to justify why a
significant proportion of distribution system sample sites are served by the surface water plant.
Some systems, such as those that serve resort communities, have dramatic fluctuations in
flow as well as population. If your system experiences widely varying demands on a seasonal
basis, you should evaluate data and operational information for different seasons separately.
When you are selecting sites, make sure that you select sites that represent the different operating
scenarios of your system.
IDSE Guidance Manual for the Final Stage 2 DBPR 7-5 January 2006
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Exhibit 7.3 Data and Tools for Selecting Different Types of
Standard Monitoring Sites
Type of Information
Type of Standard Monitoring Site
Near Entry
Point
Average
Residence Time
High
TTHM
High
HAAS
System Configuration
Pipe layout, location of storage facilities
Location of sources
Pressure Zones
Information on Population Density
Locations of Large Customers
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Water Quality and Operational Data
Disinfectant Residual Data
Stage 1 DBP Data
Other DBP Data
Microbiological Monitoring Data (e.g., HPC)
Tank Level Data, Pump Run Times
Customer Billing Records
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Advanced Tools
Water Distribution System Model
Tracer Study
X
X
X
X
X
X
Water distribution system models (e.g., hydraulic models and water quality models) and
tracer studies can be very useful in selecting average residence time and high TTHM and HAAS
sites. Hydraulic models can be used to estimate typical residence time at various locations in
your distribution system. A tracer study can provide a snapshot of water age at different
locations in your distribution system. These tools have limitations, however, and should be used
with caution. Some general guidelines are provided below.
• If your hydraulic model has not been recently calibrated or is highly skeletonized,
you may want to rely on other types of information for selecting sites, or use
modeling results in conjunction with other data.
• It is important that the hydraulic model and tracer study represent the current
distribution system configuration. If your system has undergone major changes (e.g.,
IDSE Guidance Manual for the Final Stage 2 DBPR 7-6
January 2006
-------
new tank, new pump station, major system improvement projects) since the model
was developed or the tracer study was conducted, consider using other data and tools
to select standard monitoring sites.
Chapter 6 provides detailed guidelines on using distribution system hydraulic models for the
IDSE and includes a list of technical references. Several books on distribution system modeling
also contain information on tracer studies, such as the AWWA Manual M32, Computer
Modeling of Water Distribution Systems, 2nd Edition, 2005 and Advanced Water Distribution
Modeling and Management (Walski et al., 2003).
A key resource available to many systems is the experience and knowledge of water
system personnel. Because distribution system operations and configuration are not always
well documented, experienced operations personnel can provide valuable insights to the site
selection process.
Step 2: Identify Near Entry Point Standard Monitoring Sites
Data from sites near the entry points to the distribution system represent minimum
residence time and can be used as a baseline for interpreting changes in water quality as water
travels through the system. EPA recommends that you use the following procedure to select
near entry point standard monitoring sites.
Step 2a. Determine How Many Near Entry Point Sites You Need for Standard Monitoring
Determine how many near entry point standard monitoring sites you are required to have
by referring to the Standard Monitoring Requirements - Attachment sheet in Chapter 2.
Remember that IDSE monitoring requirements (i.e., the number of monitoring sites and
sampling frequency) are based on the population served by your individual system, not the
largest population in your combined distribution system. Note the special requirements for small
consecutive systems to monitor at their consecutive system entry point.
Step 2b. Determine How Many Entry Points are in Your System
For the purposes of the IDSE, entry points are the locations where disinfected water
enters your distribution system. Entry points can convey treated surface water, disinfected water
from wells, or purchased water from a wholesale system (as long as it has been disinfected).
Entry points generally include seasonal or intermittent connections. If a well is not disinfected
or is disinfected using ultraviolet light (UV) only, you should not consider it an entry point for
the purposes of the IDSE.
Step 2c. Compare Results from Step 2a to Step 2b
• If the number of near entry point sites required matches the number of entry points in
your system, select a standard monitoring location near each entry point.
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If your system has FEWER entry points than required near entry point standard
monitoring locations, you must replace the unassigned near entry point sites with
high TTHM and HAAS standard monitoring sites to maintain the required total
number of standard monitoring sites for the IDSE. If you have an odd number of
unused near entry point sites, select an additional high TTHM site. See Example 7.1
for how a hypothetical system used this procedure to replace near entry point sites
with high TTHM and high HAAS sites for standard monitoring.
Example 7.1 System with Fewer Entry Points than Required Near Entry Point
Standard Monitoring Sites
A system has one surface water source and serves 260,000 people. According to the
Standard Monitoring Requirements - Attachment sheet in Chapter 2, the system must select
4 near-entry point sites, 6 average residence time sites, 8 high TTHM sites, and 6 high HAAS
sites. However, the system has only one source with one entry point. This system must select
its 1 near entry point site. Then it must replace the remaining 3 near entry point sites as
follows: 2 high TTHM sites and 1 high HAAS site. The system must therefore collect a total
of 10 high TTHM sites, 7 high HAAS sites, and 6 average residence time sites to go along
with its 1 near entry point site.
• If your system has MORE entry points than required near entry point standard
monitoring locations, you must take samples near entry points to the distribution
system having the highest annual water flows.
Annual flows may be calculated based on measured flows if your system has a flow
meter for each entry point location, pump or hour meter records, or other means. If
you have a totalizing flow meter at an entry point, you may use the most recent year's
readings from each meter if the measurements are representative of normal operating
conditions. For entry points where a totalizing water meter is not available, you may
use pump records or other water meter records to estimate the annual flow. You
should begin by determining the average daily flow for each entry point. Then
multiply the average daily flow at each entry point by the number of days that the
entry point was in use to determine the annual flow. See Example 7.2 on the next
page for how a hypothetical system used this procedure. Consecutive systems may
need to check with wholesalers or check records of billings/deliveries from
wholesalers.
The Stage 2 DBPR does not define near entry point sites explicitly. EPA recommends
that you locate your near entry point sites between the entrance to the distribution system and
no later than first customer. If you are a consecutive system, a sample tap at the master meter
would be an appropriate near entry point site. If you do not have a sample tap at your master
meter, consider using the first customer as your near entry point site.
IDSE Guidance Manual for the Final Stage 2 DBPR 7-8 January 2006
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Example 7.2 System with More Entry Points than Required Near Entry Point
Sample Sites
A system has two ground water sources and serves 15,000 people. According to the
Standard Monitoring Requirements - Attachment sheet in Chapter 2, the system must select 1
near entry point site. For the most recent year, approximately 70 percent of the system's water
came from Well A and the remaining 30 percent came from Well B. This system should
locate its near entry point site near Well A because this source has the higher annual flow.
Step 3: Identify Candidate Average Residence Time Sites
Average residence time is the average age of water delivered to customers in a
distribution system. Average residence time is not simply one-half the maximum residence time.
Ideally, it should be a flow-weighted or population-weighted estimate. EPA recognizes that
locating average residence time sites can be complex. A system map, used in conjunction with
disinfectant residual data and possibly hydraulic modeling (if available) can help you to identify
areas that represent average water age.
EPA recommends that you use tools and data sources available to select at least twice as
many candidate average residence time sites as required for standard monitoring. You may want
to map and color-code your candidate sites as you select them to ensure that your distribution
system is fully represented. Later, you can use additional criteria to select the most
representative standard monitoring sites from these candidate sites (see Step 7).
Step 3a: Use a Hydraulic Model or Tracer Study Data, if Available
One of the best ways to identify candidate average residence time sites is by using a
hydraulic model. If run in extended period simulation mode, the model should be able to
provide estimates of typical residence time for each node in the model. See Chapter 6 for more
information on estimating residence time using hydraulic models. Also refer to Step 1 for
cautions on using model results.
A tracer study can provide a snapshot of water age at different locations in your
distribution system. You can use tracer study results along with information on population
density and locations of large users (see Step 3c) to identify the average residence time of water
in your distribution system. Remember, though, that tracer studies done in the past may no
longer be representative of your system.
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Step 3b: Examine Disinfectant Residual Data
You can identify approximate average residence time locations in your distribution
system by calculating the average disinfectant residual concentration in your system and
identifying sites with residual concentrations near the average. When calculating average
disinfectant residual, it is important that you use data from sites that are representative of the
entire distribution system. One way to do this is by examining disinfectant residual data
collected at TCR monitoring sites. These data should be useful since the TCR requires that
monitoring sites represent water throughout the distribution system. Note that if you have
booster disinfection, then residual data collected after those locations will skew this analysis.
That data should be omitted.
See the guidelines in Exhibit 7.4 for using disinfectant residual data. If you believe that
your residual data correlates well with water age, you can use the following analysis to help
identify sites with average residence time (also see Example 7.3):
1) Calculate an average disinfectant residual at each of the TCR sites using data from
the months with the warmest water temperatures. Chlorine decay is more pronounced
in warmer temperatures so it is more common to see larger changes in chlorine
residual from one point to the next.
2) Using averages from the individual sites, calculate an overall average distribution
system residual concentration.
3) Those sites with an average residual close to the distribution system average can be
considered representative of average residence time in the distribution system. Select
sites in areas with high population densities with disinfectant residuals close to the
system average.
Caution for systems using chloramines
Chloramines are generally more stable than chlorine and may result in only small measured
differences throughout the distribution system. In this case, the method described above may not
be effective for locating average residence time sites because the change in disinfectant residual
concentration is not significant.
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Exhibit 7.4 Guidelines for Using Disinfectant Residual Data
When should I use disinfectant residual data?
Disinfectant residual in the distribution system generally decays as water age increases.
Residual concentrations typically decay faster in the warmer months, and the magnitude of
decay is more pronounced for free chlorine residuals compared to chloramine residuals.
Disinfectant residual can be helpful in locating areas of average and maximum
residence time in the distribution system. This information can be used to select candidate
average residence time, high TTHM, and high HAAS sites.
Because disinfectant residual decay can be caused by factors other than residence time,
you should be careful when interpreting your data. Other reasons why you might see a loss in
disinfectant residual are listed below.
Certain types of pipe material can exert a disinfectant residual demand. In
particular, unlined cast iron pipe can cause residuals to decline.
• Residual decline can be caused by corrosion byproducts and sediment. Customer
complaints may indicate that these are occurring in your distribution system.
• Bacteriological activity can result in a significant depletion of disinfectant residual.
HPC data is useful for determining whether this is a concern in your distribution
system.
What are the sources of disinfectant residual data?
Residual data can be from TCR sites, Stage 1 sites, operational sample sites, or sites
sampled following customer complaints.
Which data should I use to help identify candidate average residence time sites?
If you are using residual data to help identify sites with average water age, make sure
that data is from locations distributed throughout the system. You may want to use only data
from TCR sites, since these sites should be geographically representative of your system.
Make sure you don't over emphasize a particular area. You should also use data from the
warmest months that show the biggest differences in residual levels.
What if I don't have residual data throughout the system?
You may wish to take more residual data. Take care to ensure that the data is
comparable in terms of analytical method, distribution system configuration, and time of the
year to the data to which it will be compared.
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A sysl
data at 10 site
site and the 53
average chlor
candidate ave
Example 7.3 Average Disinfectant Residual Calculation
em with June, July, and August as its warmest months has free chlorine residual
s. The residual concentrations are recorded below, and the averages for each
/stem as a whole are calculated as shown. Note that sites #2, #3, and #9 have
ine residual concentrations close to the system average. These sites are good
rage residence time sites.
Site ID
#1
#2
#3
#4
#5
#6
#7
#8
#9
#10
Distribution
Svstem Ave
Monthlv Averaae (ma/L)
Jun
1.4
0.7
1.0
0.6
0.9
0.4
0.2
1.5
0.9
0.5
0.8
Jul
1.3
0.9
0.9
0.6
1.2
0.5
0.3
1.7
0.7
0.3
0.8
Aua
1.6
0.7
1.2
0.7
1.4
0.4
0.6
1.7
0.8
0.8
1.0
Site Average
(ma/U
1.4
0.8
1.0
0.6
1.2
0.4
0.4
1.6
0.8
0.5
0.9
Step 3c: Use Billing Records and a Map or Schematic
You can use billing records and information on population density, together with a map
of your system, to rule out locations for average residence time sites. You should examine your
customer billing records to determine where your large customers are located. The portions of
the distribution system serving large water users will likely have low water age and will not be
good candidate sites for average residence time. The portions of the distribution system that are
sparsely population will likely have high water age and will also not be good candidates for
average residence times. You should consider the locations of storage tanks and the sizes of
distribution system mains to the extent possible.
If your system does not have any large individual customers, you should consider
locating your candidate sites in moderately developed areas in the approximate geographic
center of the distribution system.
IDSE Guidance Manual for the Final Stage 2 DBPR 7-12
January 2006
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Step 4: Identify Candidate High TTHM Sites
It is not the intent of IDSE monitoring to identify sites with maximum daily or hourly
TTHM concentrations. Instead, you should choose candidate sites to represent areas of the
distribution system where you expect to find the highest TTHM levels throughout the year.
In general, higher water temperatures and increased water age lead to higher TTHM
concentrations in distribution systems. Exhibit 7.5 provides typical characteristics of high
TTHM sites, and Appendix A provides additional background information on TTHM formation.
Steps 4a through 4c below discuss how different types of data can be used to select
candidate high TTHM sites. Each tool and data source has its own limitations; EPA
recommends that you use all of the tools and data sources available to select at least twice as
many candidate high TTHM sites than required for standard monitoring. Later, you will use
additional criteria to select the best standard monitoring sites from these candidate sites and
determine whether all standard monitoring sites are representative of the entire distribution
system (see Step 7). You may also want to map and color-code your candidate sites as you
select them to ensure that your distribution system is fully represented.
Exhibit 7.5 Typical Characteristics of High TTHM Sites
High TTHM sites are often located
• hydraulically downstream of storage facilities and booster disinfection
• in hydraulic dead-ends, where flow of water is low or stagnant
• near the ends of the distribution system, at or before the last group of customers
Sample sites should not be located
• at a dead-end where there are no customers.
• prior to booster disinfection with chlorine
• after the last hydrant or blow-off point
Step 4a: Use a Hydraulic Model or Tracer Study Data, if Available
Calibrated, system specific hydraulic models can be very useful in identifying locations
of maximum water age that would be good candidate high TTHM sites. If run in extended
period simulation mode, the model should provide estimates of typical residence time for each
node in the model. You should select candidate sites near the nodes with the longest residence
times, provided that they are prior to the last fire hydrant and before or at the last group of
customers. Chapter 6 of this guidance manual provides more details on estimating residence
time using hydraulic models. Also refer to Step 1 for cautions on using model results.
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A tracer study can provide a snapshot of water age at different locations in the
distribution system. The locations with highest water age typically should make good candidate
high TTHM sites. Remember, though, that tracer studies done in the past may no longer be
representative of your system.
Step 4b. Use Residual Disinfectant Data
Low disinfectant residuals relative to the system average may indicate longer residence
times, and may correlate with higher TTHM concentrations. Because disinfectant residuals
typically decay faster during the summer, a review of data from the summer months may be
useful in identifying areas with consistently low residuals that are good candidate high TTHM
sites. You should evaluate residual data with caution, however, because disinfectant residual
decay can be caused by factors other than water age (e.g., corrosion, bacteriological activity).
See Exhibit 7.4 for guidelines on using disinfectant residual data as indicators of water age.
When booster disinfection is applied, the disinfectant residual will increase despite
advanced water age. TTHM levels are likely to increase after a booster disinfectant is applied
due to the greater concentration of disinfectant available for reaction with DBF precursors.
Therefore, if your system practices booster disinfection, you should locate high TTHM standard
monitoring sites after booster disinfection is applied.
Step 4c: Use a Map or Schematic and Infrastructure Data
If your system practices booster disinfection, you should locate candidate sites
downstream of your booster disinfection stations.
If your system has storage tanks or reservoirs, you should locate candidate high TTHM
sites hydraulically downstream of those tanks. Storage facilities in a distribution system increase
water age. During tank drain cycles, water age immediately downstream of a storage facility
may be significantly (e.g., several days or more) older than "fresh" water upstream of the storage
facility. As a result, areas of a distribution system receiving water that has been stored may have
higher TTHM concentrations than areas that do not receive any stored water.
You should also locate candidate sites near dead ends, particularly those that are on
smaller lines, far from major transmission lines. Sparsely populated residential areas can be
good candidate sites for high TTHM. However, be sure to locate the candidate sites before or at
the last group of customers on a dead end line. Samples taken at the very end of a dead end line
are not representative of the water received by customers.
Step 5: Identify Candidate High HAAS Standard Monitoring Sites
As with high TTHM standard monitoring sites, it is not the intent of IDSE monitoring to
identify sites with maximum daily or hourly HAAS concentrations. Instead, you should choose
high HAAS standard monitoring sites to represent areas of the distribution system where you
expect to find the highest HAAS levels throughout the year.
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Higher temperatures and increased residence time can lead to higher HAAS
concentrations. However, microorganisms can consume HAAS, causing levels to decrease. This
is know as biodegradation. Biodegradation is more likely to occur when disinfectant residual
levels are low or non-existent, particularly in warmer months. Therefore, high HAAS sites may
be located closer to the entrance to the distribution system rather than locations with very high
water age. See Appendix A for more information on HAAS formation.
Steps 5a through 5e below discuss how different types of data can be used to select
candidate high HAAS sites. Each tool and data source has its own limitations. EPA
recommends that you use all of the tools and data sources available to select twice as many
candidate high HAAS sites than required for standard monitoring. Later, you will use additional
criteria to select the best standard monitoring sites from these candidate sites (see Step 7). You
may also want to map and color-code your candidate sites as you select them to ensure that your
distribution system is fully represented.
Remember that high HAAS sites must be different from high TTHM sites for IDSE standard
monitoring.
Step 5a: Review Historical HAAS Data to Identify Trends
One way to determine if HAAS biodegrades in your system is to examine Stage 1 DBPR
monitoring or other HAAS data. You should evaluate the data over time at different locations in
the distribution system to look for trends. Consider evaluating your data to answer the following
questions:
• Are the highest HAAS values typically in the summer months?
• Are the highest HAAS values at maximum residence time locations?
• Do the highest HAAS generally occur at the same time of year and locations as high
TTHM values?
If you answered "yes" to all of these questions, it is unlikely that you are experiencing
biodegredation of HAAS at your existing monitoring sites. If you answered "no" to any of these
questions, HAAS compounds may be degrading in your system due to biological activity. In
this case you should focus on selecting sites with lower water age compared to sites you selected
for high TTHM. It is important that you also evaluate disinfectant residual data and
microbiological monitoring data (e.g., HPC data), if available, to determine whether a
monitoring location is appropriate.
Step 5b. Use a Hydraulic Model or Tracer Study
Calibrated, system specific hydraulic models can be very useful for identifying locations
of maximum residence time. If run in extended period simulation mode, the model should
provide estimates of typical residence time for each node in the model. Chapter 6 of this
IDSE Guidance Manual for the Final Stage 2 DBPR ~5 January 2006
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guidance manual provides more details on estimating residence time using hydraulic models.
Also refer to Step 1 for cautions on using model results.
You should consider selecting high HAAS candidate sites near the nodes with the longest
residence times, provided that they are prior to the last fire hydrant and before or at the last
group of customers. You should examine chlorine residual data and HPC data if available to
ensure that these locations are not susceptible to biodegradation (see Steps 5c and 5d). However,
if you have determined that biodegradation is occurring in your distribution system in step 5a,
you should focus on sites with lower water age.
A tracer study can provide a snapshot of water age at different locations in the
distribution system. The locations with highest water age typically should make good candidate
sites, unless disinfectant residual levels are too low. Remember, though, that tracer studies done
in the past may no longer be representative of your system.
Step 5c. Use Residual Disinfectant Data
Low disinfectant residuals relative to the system average may indicate longer residence
times, and may correlate with higher HAAS concentrations (unless biodegradation is occurring
in the distribution system as discussed in step 5a). Sites with very low or non-existent residuals,
however, are more likely to have biodegradation of HAAS and would not be good candidate high
HAAS sites.
You should not select high HAAS sites in locations that regularly or in the summer months have
free chlorine residuals less than 0.2 mg/L or with chloramine residuals less than 0.5 mg/L.
Because disinfectant residuals typically decay faster during the summer, a review of data
from the summer months may be useful in identifying areas with consistent disinfectant residuals
that are good candidate high HAAS sites. You should consider locating candidate high HAAS
sites where disinfectant residuals are less than the system average, but still regularly above 0.2
mg/L for free chlorine systems and above 0.5 mg/L for chloramine systems.
When booster disinfection is applied, the disinfectant residual will increase despite
advanced water age. HAAS levels are likely to increase after a booster disinfectant is applied
due to the greater concentration of disinfectant available for reaction with DBF precursors and
decreased potential for biodegradation. Therefore, if your system practices booster disinfection,
you should locate high HAAS standard monitoring sites after booster disinfection is applied.
Step 5d. Use Heterotrophic Plate Count Data, if Available
In addition to disinfectant residual data, HPC data can be extremely useful for identifying
areas in your distribution system that are biologically active. If locations in the distribution
system have high HPC levels compared to other locations (particularly in the summer months),
they should be excluded as candidate high HAAS sites.
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Step 5e. Use a Map or Schematic and Infrastructure Data
Geographic locations for high HAAS sites depend on whether your system experiences
biodegredation in the distribution system. See Step 5a for guidance on evaluating historical
HAAS data for trends, and Steps 5c and 5d to evaluate other data to assess the potential for
biodegredation.
If you do not believe that HAAS biodegrades in your system, follow the same general
guidelines for locating high TTHM sites for locating high HAAS sites (see Step 4c). If you do
believe that HAAS biodegrades in your system, you should consider locating HAAS sites in
areas with lower water age in the center regions of your system where you maintain high
disinfectant residuals.
Step 6: Plot Sites on a Distribution System Map
A key step in selecting standard monitoring sites from candidate sites is plotting all
candidate sites on a map of your distribution system. If you have not already done so, locate all
Stage 1 DBPR compliance monitoring locations, near entry point sites, and candidate average
residence time, high TTHM, and high HAAS sites on your water distribution map. Consider
color coding the sites by the site type.
As noted in Step 1, your map should also contain the system attributes that will be useful
in identifying representative standard monitoring sites, such as:
• Lay out of pipes
• Storage facilities
• Pumping stations
• Booster disinfection stations
• Pressure zone boundaries
If possible, your map should also include the location of large water users, areas of significant
development, and areas with relatively few customers.
Step 7: Select Standard Monitoring Sites from Candidate Sites
As described in the previous sections, various data sources and tools can be used to
identify standard monitoring sites. If you followed the recommended procedures, you should
have more candidate sites than are required for standard monitoring. This will allow you to
select a final set of standard monitoring locations that represents the entire distribution system,
considering the whole picture in addition to the specific characteristics you examined in steps 3
through 6. How should you prioritize the data and combine data sources and tools to select
standard monitoring sites? This section addresses this question by providing general guidelines
for (1) evaluating sites and determining if they meet expectations, and (2) narrowing down the
candidate sites to standard monitoring sites. Remember that you must write a justification for
each standard monitoring site and a summary of data considered (see Step 8), to be included in
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your IDSE standard monitoring plan. You may want to consider how you will write your
justifications as you examine your candidate sites.
You should always visually confirm that standard monitoring sites, in combination with
existing Stage 1 DBPR monitoring sites, provide geographic coverage of the distribution system.
You should also visually confirm that standard monitoring sites are in expected areas of high and
average residence time (as predicted by a hydraulic model or other data source). You should
confirm that you are not missing key areas that may not have been sampled in the past. If you
have GIS capabilities, queries can be extremely useful in automating the site selection process.
Experienced systems operations personnel can provide valuable input during this process.
The following are general guidelines for choosing standard monitoring sites from the list
of candidate sites identified.
Step 7a. Evaluate Sites. Do They Meet Expectations?
The purpose of this step is to confirm that your candidate sites cover key areas and to add
candidate sites if appropriate. The following questions may be useful as you evaluate all
candidate sites together on the map:
• Are candidate high TTHM sites located in the extremities of the distribution system?
• Are candidate high TTHM sites generally downstream of storage facilities and
booster disinfection stations (if booster disinfection is practiced)?
• Are candidate high HAAS sites in areas where you can regularly maintain
disinfectant residual levels greater than 0.2 mg/L for chlorine and 0.5 mg/L for
chloramine?
• Are there any other areas where you suspect water age is high that are not represented
by a candidate high TTHM (and possibly high HAAS) site?
Step 7b. Select Standard Monitoring Sites
Now that you have plotted the candidate sites on the map, you will need to choose the
best locations to represent each type of site. The following issues should be considered when
making these choices:
• Look for geographic representation. Select sites that are geographically diverse
from the other standard monitoring sites and existing Stage 1 compliance monitoring
locations. EPA recommends that you locate at least one of the high TTHM standard
monitoring sites in a remote area of the distribution system. If your distribution
system contains hydraulically isolated portions, you should represent as many of
these as possible with at least one standard monitoring site. If you are only required
to select one high TTHM site, it is strongly recommended that you locate this site far
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away from the treatment plant, near the last group of customers (but prior to the last
fire hydrant).
• Look for hydraulic representation. Select standard monitoring sites in
hydraulically different areas. Even if sites are geographically near each other, they
may represent different pressure zones. You should also select sites that represent
mixing zones if multiple sources with different water quality characteristics are used.
• Use sites that "multi-task." Prioritize sites that meet the multiple siting criteria and
those identified based on more than one data source. For example, a candidate high
TTHM site that has low disinfectant residual, is near the edge of the distribution
system and is downstream of a tank would be an excellent standard monitoring site.
Consider site access. Select standard monitoring sites for which access will not be
an issue. Sites should remain accessible over the long term.
• Use existing TTHM and HAAS monitoring data to prioritize choices. If you have
more than enough sites in a given area of the distribution system and no other data
favors one over the other, use existing TTHM or HAAS monitoring results (if
available) to prioritize sites. For example, if disinfectant residual data are the same
for three sites over the same periods, then the DBF data can be used to select a high
TTHM or HAAS standard monitoring site. Remember that you cannot use Stage 1
DBPR compliance monitoring sites as standard monitoring sites.
Step 8: Write Justifications and a Summary of Data
Your final steps in selecting standard monitoring sites are to write a justification for each
site and write the summary of data you used to justify your site selection.
Step 8a. Write Justification for Each Standard Monitoring Site
You must write a justification for each standard monitoring site. Justifications should
document the key site characteristics that led you to select the site for standard monitoring. They
should be brief, but as specific as possible. Some characteristics you should consider including
in your justifications are as follows:
• Pipe size, or range of pipe sizes in the area
• Relationship to storage facilities
• Estimated water age, if available
Source of water (if the distribution system is served by more than one source)
• Range of disinfectant residual concentrations (if lower in the summer, provide
summer values)
• For HAAS sites, range of HPC levels, if available
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Not all systems will have all data types in this list; include the information that is available to
your system in your justification. Hypothetical examples of justifications for each type of
standard monitoring site are below. Additional examples of justifications are provided in
Appendices H and I of this guidance manual and in the EPA manual, Initial Distribution System
Evaluation Guide for Systems Serving < 10,000 People.
• High TTHM site: This site is served by our surface water source and is at the end of
one of our pressure zones. It is hydraulically downstream of Tank X, one of our
largest storage facilities. The site is a gas station in a residential area with
predominantly 4 and 6 inch pipes. Chlorine residuals at this site are below system
average, ranging from 1.2 to 1.5 mg/L in the summer.
• High HAAS site: This site is served by our surface water source and is located on an
8-inch pipe in a commercial area. It is in an area of average to high water age that
has a history of high chlorine residual concentrations (2 to 2.2 mg/L in the summer).
HPC levels for this site have historically been low compared to the rest of the system
(< 500).
• Average residence time site: This site is in the geographic center of Pressure Zone 2
and has a chlorine residual level close to the system average (1.5 mg/L).
• Near entry point: This site is our finished water sampling location for Surface Water
Treatment Plant X. We have more entry points than required near entry point sites,
so we selected this entry point because it has the highest average daily flow
compared to our other sources.
Step 8b. Write a Summary of Data
You must provide a summary of data you relied on to justify standard monitoring
location selections. You should describe the water quality data you reviewed, map features you
considered, ranges of relevant water quality data, and water sources and seasonal operations if
applicable, and tools you used to select your standard monitoring sites. An example summary is
provided below. Additional examples of data summaries are provided in Appendices H and I of
this guidance manual and in the EPA manual, Initial Distribution System Evaluation Guide for
Systems Serving < 10,000 People.
We used our up-to-date water distribution system map to plot data and select sites. Our
map shows locations and sizes of all pipes, storage tanks, booster pumping stations, and
sources. We noted the location of large users and new developments. We analyzed
disinfectant residual collected at TCR sites in 2004 and 2005 and plotted average
concentrations from the summer months on our map. Summer disinfectant levels ranged
from 2.5 mg/L at the plant to 0.3 mg/L in the distribution system. The distribution system
average was between 0.9 and 1.1 mg/L. We also indicated average TTHM and HAAS
concentrations for our Stage 1DBPR sites for 2005 data. TTHM concentrations ranged
from 0.035 mg/L through 0.085 mg/L and HAAS concentrations ranged from 0.015 mg/L
through 0.03 7 mg/L.
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We reviewed our tank level data and determined average water age inside the tank to
help identify areas with higher water age. We have some water age information from a
tracer study of our distribution system done in 1995. We have estimated the highest
water age in the distribution system to be approximately 4.5 days. We also highlighted
two problem areas that our operations staff say are places where we get repeat customer
complaints and low residuals.
7.1.2 Selecting Your Peak Historical Month and Determining Standard Monitoring
Schedule
Determining Peak Historical Month
The Stage 2 DBPR defines the peak historical month as the month with the highest
TTHM or HAAS levels or the warmest water temperature. It is meant to represent "worst case"
conditions when DBFs are the highest. You must review available compliance, study, or
operational data to determine the peak historical month for TTHM or HAAS levels or warmest
water temperature. You can use Worksheet 7.1 on the next page to determine your peak
historical month.
In some cases, you may find data in addition to TTHM, HAAS, and temperature data
helpful in selecting your peak historical month. As described in Appendix A, key factors
affecting TTHM and HAAS formation are temperature, water age, and concentration of DBF
precursors (i.e., organic compounds that react with disinfectants to produce DBFs). Some
systems may regularly see an increase in total organic carbon (TOC) levels in the spring or fall.
If your TTHM and HAAS monitoring does not capture a seasonal increase in TOC, you may
want to consider the month with highest TOC when selecting your peak historical month.
Seasonal changes in water age in your distribution system can be another influencing
factor in determining the worst-case conditions when DBFs are the highest. For example, some
systems may experience a decrease in peak usage in the fall, thereby increasing residence time in
the distribution system. The water temperature in the fall may not be as high as it was in the
summer months, but it still may be relatively high, such that increased residence time
significantly increases TTHM and HAAS formation. In this scenario, you should consider water
age when selecting your peak historical month.
If you based the selection of your peak historical month on data other than TTHM,
HAAS, and temperature, you should document the basis for selection in your IDSE standard
monitoring plan.
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Worksheet 7.1 Selecting the Peak Historical Month Page i of i
A. Do you have more than one water source (e.g., treatment plant
or consecutive system entry point) in your system? D Yes D No
If Yes, you should identify the source associated with the highest
TTHM and HAAS levels in your system based on your Stage 1
DBPR monitoring data. You should use data from this source for
selecting your peak historical month. Continue to STEP B
If No, continue to STEP B
B. Do you have monthly or quarterly TTHM and HAAS data? D Yes D No
If Yes, you should determine in which month your TTHM and HAAS levels are the
highest.
What if the highest TTHM and/or HAA5 levels occur at different times during
different years? You should choose the year of data that is most representative
of typical system operating and weather conditions.
What if the highest TTHM and HAAS levels occur in different months? You
should consider which contaminant is of more concern. If one contaminant
clearly shows a higher overall trend and is closer to the MCL, you should
choose the month in which that contaminant is highest.
Choose the month with the highest TTHM and HAAS levels as your peak
historical month. Stop here.
If No, continue to STEP C
C. Use temperature data to select your peak historical month
Calculate the average water temperature for each summer month to identify the
month of warmest water temperature. If available, use data from several years to
determine when the warmest water temperature occurs. If warmest
temperature occurs in different months in different years, select the year(s)
that are most typical of climatological and water quality data and water use Jjjjj;
for your region.
Remember, in your standard monitoring plan you should indicate the source used to
select your peak historical month and the basis for selecting it (high TTHM, high
HAA5, and/or temperature)
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Determining Standard Monitoring Schedule
You must take one round of standard monitoring samples during the peak historical
month. If you serve more than 499 people, you must also conduct sampling at equal intervals
before and/or after the peak historical month, based on your required sampling frequency. You
can find your required sampling frequency on the Standard Monitoring Requirements -
Attachment sheet in Chapter 2. Be sure to plan your monitoring so that all sampling is complete
by the deadline on your requirements summary sheet in Chapter 2.
The intent of the required time interval is to ensure that samples represent the quality of
water over an extended period and do not over-emphasize either high or low concentrations of
TTHM or HAAS that may occur seasonally. For example, a system on quarterly monitoring
could sample in the third full week of every third month. You should keep in mind holidays
and sampling schedules for other water quality programs when determining your standard
monitoring schedule.
7.1.3 Preparing Your Standard Monitoring Plan
Every system that conducts IDSE standard monitoring must prepare and submit an
Standard Monitoring Plan. You should submit the plan to the Information Processing and
Management Center (IPMC) for review by EPA or your state. See Section 1.4 of this guidance
manual for information on how to submit your plan to the IPMC.
EPA has developed a Standard Monitoring Plan Form (Form 6), presented in this
section and available electronically as part of the IDSE Tool. You are not required to use this
form; however, if you choose not to use it, refer to Exhibit 7.1 on page 7-3 for a list of the
minimum elements you must include in your standard monitoring plan.
The IDSE Tool creates a custom form for your system and provides /
links to technical guidance from this manual. The tool is available on EPA's (
website at http://www.epa.gov/safewater/disinfection/stage2. IDSE
Your deadlines for submitting your standard monitoring plan and conducting standard
monitoring can be found on your requirements summary sheet in Chapter 2. If EPA or your state
does not approve or request modifications to your plan, or notify you that your plan is still under
review within 12 months after the deadline for plan submission, you may consider the plan
approved.
IDSEGuidance Manual for the Final Stage 2 DBPR 7-23 January 2006
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The standard monitoring plan form includes the following sections:
I. General Information
II. IDSE Requirements
III. Selecting Standard Monitoring Sites
IV. Justification of Standard Monitoring Sites
V. Peak Historical Month and Standard Monitoring Schedule
VI. Planned Stage 1 DBPR Compliance Monitoring Schedule
VII. Distribution System Schematic
VIII. Attachments
Sections of the form with an asterisk (*) are required by the Stage 2 DBPR. Examples of
completed standard monitoring plans using this form are provided in Appendices H and I of this
guidance manual and in the EPA manual, Initial Distribution System Evaluation Guide for
Systems Serving < 10,000 People. The rest of this section provides guidance on the completion
of this form.
I. General Information
LA. PWS Information* - Important definitions for classifying your system are
provided in the definitions section at the beginning of this guidance manual. If
you have any questions on this section, contact EPA or your state.
PWSID - Enter your PWSID identification number here. This number is typically
assigned by your state.
PWS Name - Enter the name of your system here.
PWS Address - Enter the primary mailing address for your water system here.
Population Served - Enter the number of people served by your PWS.
Remember, this is your RETAIL population served, not including the population
served by consecutive systems that purchase water from you.
System Type - Put a check mark in the appropriate box to identify whether your
system is a CWS or a NTNCWS. Definitions for CWS and NTNCWS can be
found in the definitions section at the beginning of this guidance manual.
Source Water Type - Put a check mark in the appropriate box to identify whether
your system is a subpart H system or a ground water system. If you use any
surface water or GWUDI as a source, mark the subpart H box. Definitions for
subpart H system (including GWUDI) and ground water system can be found in
the definitions section at the beginning of this guidance manual.
Buying/Selling Relationships - Put a check mark in the appropriate box to identify
whether your system is a consecutive system, a wholesale system, or neither. If
IDSE Guidance Manual for the Final Stage 2 DBPR ~4 January 2006
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you are both a consecutive and wholesale system (e.g., you buy and sell water),
check both boxes. Definitions for consecutive system and wholesale system can
be found in the definitions section at the beginning of this guidance manual and
in Appendix D.
IB. Date Submitted* - Enter either the date that you are submitting the form
electronically, putting it in the mailbox, or dropping it off with an express
delivery service. Be sure to submit your standard monitoring plan before the
deadline found on your requirements summary sheet.
1C. PWS Operations - This section asks questions about your system to help inform
EPA and state personnel during the plan review process.
Residual Disinfectant Type - Put a check mark in the appropriate box to identify
the type of disinfectant you most often use to maintain a residual in your
distribution system (not necessarily the same disinfectant used for primary
disinfection at the treatment plant). If you use chloramine but switch to free
chlorine for a short time, you should still check chloramine only. If you use
chloramine and chlorine regularly in your system (e.g, 4 months of free chlorine
and 8 months of chloramines), check both chlorine and chloramine. If you
maintain your residual with a disinfectant other than chlorine or chloramines (e.g.,
chlorine dioxide), you should place a check next to the box marked "Other" and
enter the type of disinfectant you use in the blank next to "Other".
Number of Disinfected Sources - Enter the total number of sources that deliver
disinfected water to your distribution system. If you connect to a single
wholesale system at a number of locations in your distribution system, consider
this one source. Multiple wells that are disinfected at a common treatment plant
should also be considered one source. Do not count wells that are not disinfected
or are disinfected by UV only.
ID. Contact Person* - Enter the contact information of the person who is submitting
the form. This should be the person who will be available to answer questions
from EPA and/or state reviewers.
II. IDSE Requirements*
II. A Number of Sites - Refer to the Standard Monitoring Requirements - Attachment
sheet in Chapter 2. Copy the numbers from the "IDSE Standard Monitoring
Requirements" table that correspond to your source type and the population
served by your system.
Note that you may need to adjust the number of each site type if you have fewer
entry points than required near entry point sites (see Step 1 in Section 7.1.1). This
IDSE Guidance Manual for the Final Stage 2 DBPR 7-25 January 2006
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adjustment should be reflected in your site selection and justification in Section
IV. Your total should always be the same.
II.B. Schedule - Enter the schedule for your system based on the letter sent to you
from
EPA or your state. See Chapter 2 for more information on the letter.
II. C. Standard Monitoring Frequency - Refer to the Standard Monitoring
Requirements Attachment sheet in Chapter 2. Locate the monitoring frequency
from the "IDSE Standard Monitoring Requirements" table that corresponds to
your source type and the population served by your system. Put a check mark in
the box corresponding to that monitoring frequency.
III. Selecting Standard Monitoring Sites
III. A. Data Evaluated - Put a check mark in each box corresponding to the data that you
used to select each type of standard monitoring site. Water quality data may be
compliance data or operational data.
III.B. Summary of Data* - In the space provided (or in an attached writeup), provide a
summary of the data you used to justify your site selection. See Step 8b in
Section 7.1.1 of this manual for guidance.
IV. Justification of Standard Monitoring Sites* Enter the site ID from the distribution
schematic, site type (whether it is near an entry point, average residence time, high
TTHM, or high HAAS), and justification. Justification for each standard monitoring site
should include the system characteristics that led you to choose it as a standard
monitoring site. See Step 8a in Section 7.1.1 of this manual for guidance. If you have
fewer near entry points than required near entry point monitoring locations, be sure to
replace the extra near entry point sites with high TTHM or high HAAS sites.
Note that there is only space for 8 monitoring sites on this sheet. If you are a ground
water system serving more than 499,999 people or a subpart H system serving more than
49,999 people you are required to monitor at more than 8 sites. Therefore, you will need
to attach additional sheets.
V. Peak Historical Month and Proposed Standard Monitoring Schedule
V. A. Peak Historical Month* - Enter the month that you determined to be your peak
historical month. See Section 7.1.2 and Worksheet 7.1 for guidelines on
selecting your peak historical month.
V.B. If Multiple Sources. Source Used to Determine Peak Historical Month - If your
system has only one source, write "N/A" here. If you have more than one source,
write the name of the source you used as the basis for determining peak historical
IDSE Guidance Manual for the Final Stage 2 DBPR 7-26 January 2006
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month. For example, if a system has one surface water, one ground water, and
one purchased ground water source, it is likely that they relied heavily on data
from the surface water source to select their peak historical month. This system
would write "surface water source" in the blank provided.
V.C Peak Historical Month Based On* - Put a check mark in the appropriate box to
identify the basis for determining your peak historical month. If your peak
historical month is supported by more than one parameter (e.g., peak historical
month is month of high TTHM and maximum temperature), check each box that
applies. If you used data other than TTHM, HAAS, and temperature data to
select your peak historical month (e.g., you used TOC data and/or water age
data), describe how you used additional data here.
V. D. Proposed Standard Monitoring Schedule* - Enter the ID for each standard
monitoring site in the table (verify that these match the IDs you enter in Section
IV and on your schematic). Enter your proposed sampling schedule for the
number of monitoring periods identified in Section II.C. The entry can be a
specific date or week and can be in a number of different formats. For example:
7/9/07
2nd week in Nov ' 07
Week of 7/9/07
Remember that at least one monitoring period must be during the peak historical
month identified in Section V.A. Note that there is only space for 8 monitoring
sites on this sheet. If you are a ground water system serving more than 499,999
people or a subpart H system serving more than 49,999 people you are required to
monitor at more than 8 sites. Therefore, you will need to attach additional sheets.
VI. Planned Stage 1 DBPR Compliance Monitoring Schedule* Enter the projected
sampling schedule for the number of Stage 1 DBPR monitoring periods in which you will
conduct Stage 1 DBPR monitoring during your IDSE standard monitoring. Verify that
site IDs in this table match the IDs on your distribution system schematic. If you are
required to monitor at more than 8 Stage 1 DBPR locations you will need to attach
additional sheets. You may also want to attach your Stage 1 DBPR monitoring plan.
VII. Distribution System Schematic* Attach a distribution system schematic to your
monitoring plan. Your schematic must include the locations of entry points, sources,
storage facilities, standard monitoring sites, and Stage 1 compliance monitoring sites.
IDSE standard monitoring plans will not be considered confidential business information
(CBI) and are subject to the Freedom of Information Act (FOIA). Therefore, your
distribution system schematic should not contain information that poses a security risk
to your system. EPA suggests that you consider one of the following options for
submitting distribution system schematics:
IDSE Guidance Manual for the Final Stage 2 DBPR 7-2 7 January 2006
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Option 1: Distribution system schematic with no landmarks or addresses
indicated. Show locations of sources, entry points, storage facilities, standard
monitoring locations, and Stage 1 compliance monitoring locations (required).
Also include pressure zone boundaries and locations of pump stations. Provide
map scale.
• Option 2: City map without locations of pipes indicated. Show locations of
sources, entry points, storage facilities, standard monitoring locations, and Stage 1
compliance monitoring locations (required). Also include boundaries of the
distribution system, pressure zone boundaries and locations of pump stations.
Provide map scale.
Schematics should be as clear and easy to read as possible. They should typically be
submitted on a scale of between 1:4,000 and 1:8,000; however, larger-scale drawings are
acceptable as long as systems components can still be clearly shown. All sizes from 8V2
inches x 11 inches to larger, plan-sized sheets are acceptable. If electronic versions are
submitted, use one of the following file types:
• Adobe PDF file (*.pdf)
• Microsoft Word (*.doc)
• WordPerfect (*.wpd)
• Image file (*.gif, *.bmp, *.jpg, *jpeg)
VIII. Attachments Put a check mark in each of the boxes corresponding to any attachments
that you have included in your report.
A distribution system schematic is required. Refer to Section VII for details.
Note that there is only space for 8 monitoring sites in Section IV and Section VI. If you
are a ground water system serving more than 499,999 people or a subpart H system
serving more than 49,999 people, you will need to attach additional sheets for Section IV
and Section VI.
If you submit your standard monitoring plan electronically, you also have the option to
submit attachments in hard copy. Include a note in your electronic standard monitoring
plan explaining that attachments are being submitted in hard copy, and mail the hard
copy to the IPMC mailing address in your Requirements Summary Sheet. The IPMC
will match the hard copy submission with your electronic submission when it is received.
Enter the total number of pages in your monitoring plan (including attachments) in the
blank at the bottom of this section. This will allow EPA or your state to ensure that all
pages were received.
IDSE Guidance Manual for the Final Stage 2 DBPR 7-28 January 2006
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Form 6: Standard Monitoring Plan pageiote
I. GENERAL INFORMATION
A. PWS Information*
PWSID:
| B. Date Submitted*
PWS Name:
PWS Address:
City:
State: Zip:
Population Served:
System Type: Source Wat<
D CWS D Subpart
D NTNCWS D Ground
C. PWS Operations
Residual Disinfectant Type: n Chlor
Number of Disinfected Sources: S
3r Type: Buying / Selling Relationships:
H D Consecutive System
D Wholesale System
D Neither
ne n Chloramines n Other:
surface GWUDI Ground Purchased
D. Contact Person*
Name:
Title:
Phone #:
Fax#:
E-mail:
II. IDSE REQUIREMENTS*
A. Number of Sites B. Schi
Total:
Near Entry Point: D Schec
Avg Residence Time: D Schec
High TTHM: D Schec
High HAAS: D Schec
3dule C. Standard Monitoring Frequency
Jule 1 n During peak historical month
. I 2 (1 monitoring period)
Jule 3 n Every 90 days (4 monitoring periods)
Jule 4 n Every 60 days (6 monitoring periods)
IDSE Guidance Manual for the Final Stage 2 DBPR 7-29
January 2006
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Form 6: Standard Monitoring Plan
Page 2 of 6
I. SELECTING STANDARD MONITORING SITES
A. Data Evaluated Put a "/" in each box corresponding to the data that you used to
select each type of standard monitoring site. Check all that apply.
Data Type
Type of Site
Near
Entry Pt.
Avg. Residence
Time
High
TTHM
High
HAAS
System Configuration
Pipe layout, locations of storage facilities
Locations of sources and consecutive
system entry points
Pressure zones
Information on population density
Locations of large customers
Water Quality and Operational Data
Disinfectant residual data
Stage 1 DBP data
Other DBP data
Microbiological monitoring data (e.g., HPC)
Tank level data, pump run times
Customer billing records
Advanced Tools
Water distribution system model
Tracer study
B. Summary of Data* Provide a summary of data you relied on to justify standard
monitoring site selection, (attach additional sheets if needed)
IDSE Guidance Manual for the Final Stage 2 DBPR 7-3 0
January 2006
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Form 6: Standard Monitoring Plan
PageS of 6
IV. JUSTIFICATION OF STANDARD MONITORING SITES*
Standard
Monitoring
Site ID
(from map)1
Site Type
Justification
n Near Entry Pt
n Avg. Res. Time
D High TTHM
D High HAAS
n Near Entry Pt
n Avg. Res. Time
D High TTHM
D High HAAS
n Near Entry Pt
n Avg. Res. Time
D High TTHM
D High HAAS
n Near Entry Pt
n Avg. Res. Time
D High TTHM
D High HAAS
n Near Entry Pt
n Avg. Res. Time
D High TTHM
D High HAAS
n Near Entry Pt
n Avg. Res. Time
D High TTHM
D High HAAS
n Near Entry Pt
n Avg. Res. Time
D High TTHM
D High HAAS
n Near Entry Pt
n Avg. Res. Time
D High TTHM
D High HAAS
1 Verify that site IDs match IDs in Section IV and on your distribution system schematic (See Section VII
of this form). Attach additional copies if you are required to select more than 8 standard monitoring
locations or need more room.
IDSE Guidance Manual for the Final Stage 2 DBPR 7-31
January 2006
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Form 6: Standard Monitoring Plan
Page 4 of 6
V. PEAK HISTORICAL MONTH AND PROPOSED STANDARD MONITORING SCHEDULE
A. Peak Historical Month*
B. If Multiple Sources, Source Used to Determine Peak Historical Month
(write "N/A" if only one source in your system)
C. Peak Historical Month Based On* (check all that apply)
D High TTHM n Warmest water temperature
D High HAAS
If you used other information to select your peak historical month, explain here
(attach additional sheets if needed)
D. Proposed Standard Monitoring Schedule*
Standard Monitoring
Site ID
(from map) 1
Projected Sampling Date (date or week)2
period 1
period 2
period 3
period 4
period 5
period 6
1 Verify that site IDs match IDs in Section IV and on your distribution system schematic (See
Section VII of this form). Attach additional copies if you are required to select more than 8
standard monitoring locations.
2 period = monitoring period. Complete for the number of periods from Section II. C. Can list exact
date or week (e.g., week of 7/9/07)
IDSE Guidance Manual for the Final Stage 2 DBPR 7-32
January 2006
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Form 6: Standard Monitoring Plan
Page 5 of 6
VI. PLANNED STAGE 1 DBPR COMPLIANCE MONITORING SCHEDULE*
Stage 1 DBPR
Monitoring Site
ID (from map) 1
Projected Sampling Date (date or week) 2
Period 1
Period 2
Period 3
Period 4
1 Verify that site IDs match IDs on your distribution system schematic (See Section VII of
this form). Attach additional copies if you are required to monitor at more than 8 Stage 1
DBPR sites.
2 period = monitoring period. Complete for the number of periods in which you must conduct
Stage 1 DBPR monitoring during IDSE monitoring. Can list exact date or week (e.g., week
of 7/9/07)
VII. DISTRIBUTION SYSTEM SCHEMATIC*
ATTACH a schematic of your distribution system.
Distribution system schematics are not confidential and should not contain information
that poses a security risk to your system. EPA recommends that you use one of two
options:
Option 1: Distribution system schematic with no landmarks or addresses
indicated. Show locations of sources, entry points, storage facilities, standard
monitoring locations, and Stage 1 compliance monitoring locations (required). Also
include pressure zone boundaries and locations of pump stations. Provide map
scale.
Option 2: City map without locations of pipes indicated. Show locations of
sources, entry points, storage facilities, standard monitoring locations, and Stage 1
compliance monitoring locations (required). Also include boundaries of the
distribution system, pressure zone boundaries and locations of pump stations.
Provide map scale.
IDSE Guidance Manual for the Final Stage 2 DBPR 7-33
January 2006
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Form 6: Standard Monitoring Plan page6 of6
VIM. ATTACHMENTS
D Distribution System Schematic* (Section VII).
D Additional sheets for the summary of data or site justifications (Sections III and IV).
D Additional copies of Page 3 for justification of Standard Monitoring Sites (Section
IV). Required if you are a subpart H system serving more than 49,999 people or
a ground water system serving more than 499,999 people.
D Additional sheets for explaining how you used data other than TTHM, HAAS, and
temperature data to select your peak historical month (Section V).
D Additional copies of Page 4 for proposed monitoring schedule (Section V).
Required if you are a subpart H system serving more than 49,999 people or a
ground water system serving more than 499,999 people.
D Additional sheets for planned Stage 1 DBPR compliance monitoring schedule
(Section VI).
Total Number of Pages in Your Plan
Note: Fields with an asterisk (*) are required by the Stage 2 DBPR
IDSE Guidance Manual for the Final Stage 2 DBPR 7-34 January 2006
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7.2 Conducting Standard Monitoring
Conducting standard monitoring is an integral part of the IDSE. The results of standard
monitoring, along with the results of Stage 1 DBPR compliance monitoring, must be used to
select the best sites for Stage 2 DBPR compliance monitoring and must be documented in your
IDSE report.
Remember, you must submit your standard monitoring plan before you begin standard
monitoring. If EPA or your state does not approve or request modifications to your plan, or
notify you that your plan is still under review within 12 months after the deadline for plan
submission, you may consider the plan approved. You must conduct standard monitoring
according to the approved monitoring plan.
This section presents sampling requirements and tips for sample collection for
conducting standard monitoring.
REMINDER: you must continue to collect samples and comply with the Stage 1 DBPR during
the IDSE. Results from standard monitoring should not be used for making Stage 1 compliance
determinations.
Your Requirements
You must conduct standard monitoring according to the schedule and at each of the
monitoring locations listed in your standard monitoring plan. If you deviate from the approved
plan for any reason (e.g., a site was not accessible on the planned week and you needed to
sample during the next week), you must include an explanation for the deviation in your IDSE
report.
During each sampling event, you must collect a dual sample set (i.e., two samples) at
each location. One sample must be analyzed for TTHM and the other must be analyzed for
HAAS. Two samples are required because the analytical methods used for the two groups of
contaminants require different sample preservation methods. You must use EPA-approved
methods for analysis of your TTHM and HAAS samples. More information on EPA-approved
methods can be found in Appendix C.
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Tips for Sample Collection
As you conduct standard monitoring, you should keep in mind the following tips:
Use appropriate sample bottles. You should use
sample bottles that already contain the appropriate
dechlorinating agent and preservative for sample
collection. You should contact your lab for a
recommended sampling and preservation protocol. A
typical sampling protocol can be found in Appendix C.
• Flush your sample tap. If you collect samples from a tap, you should open the cold
water tap and allow the line to flush until the water temperature has stabilized
(usually about 3-5 minutes). If you collect a sample at a hydrant or blow-off, the
flushing time only needs to be long enough to purge the connecting line to the main.
The purpose of this step is to ensure the sample does not represent stagnant water that
has been sitting for a long time in the water line between the street and the faucet.
The sample should represent the water flowing through the distribution system at the
chosen sampling point.
• Collect cold water samples. If you collect indoor samples you should collect them
from a cold water line.
Collect additional water quality data. You may wish to collect additional water
quality data, such as disinfectant residual and temperature data, at the time of DBF
sample collection. This information can be helpful as you interpret standard
monitoring results (e.g., unusually low residual at a location could mean unusually
high residence time).
• Re-sample if a sample is lost or broken. If a sample bottle is lost or broken after
sample collection, you should re-sample as soon as possible after the loss occurs.
Only the lost sample needs to be recollected, not the entire sample set that was
collected together. Make sure to note the loss of sample and resample date as a
deviation in your IDSE report.
If you need to change an IDSE standard monitoring sampling location for reasons beyond
your control, or if you miss a required sampling period entirely, you should contact EPA or your
state so they can approve your re-sampling strategy.
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7.3 Selecting Stage 2 DBPR Compliance Monitoring Sites and Preparing the
IDSE Report
Every system that conducts standard monitoring must use results from Stage 1 DBPR
compliance monitoring and standard monitoring to select Stage 2 DBPR compliance monitoring
sites. You must follow a specific protocol, as laid out in the Stage 2 DBPR, to select
compliance sites unless you decide to recommend alternative Stage 2 compliance monitoring
sites to your state or EPA.
You must include your monitoring results and recommended Stage 2 compliance
monitoring sites in an IDSE Report. You should submit your IDSE report to the Information
Processing and Management Center (IPMC) for review by EPA or your state. See Section 1.4 of
this guidance manual for information on how to submit your plan to the IPMC.
This section presents the required protocol for selecting Stage 2 DBPR compliance
monitoring sites and provides guidance for preparing an IDSE report.
EPA has developed an IDSE Report for Standard Monitoring Form
(Form 7), presented in Section 7.3.3 and available electronically as part of the /\
IDSE Tool. You are not required to use this form; however, if you choose not to (
use it, refer to Exhibit 7.6 for a list of the minimum elements you must include in __
your IDSE report. Examples of completed reports can be found in Appendices H
and I. The IDSE Tool is available on EPA's website at
http://www.epa.gov/safewater/disinfection/stage2.
Exhibit 7.6 Required Elements of Your IDSE Report for Standard Monitoring
• Explanation of any deviations from approved standard monitoring plan
TTHM and HAAS analytical results from Stage 1 DBPR monitoring and IDSE
standard monitoring
Recommendations and justification of Stage 2 DBPR monitoring sites and
sampling dates
If changed from the approved standard monitoring plan:
Distribution system schematic
Population served by the system
System type (subpart H or ground water)
IDSE Guidance Manual for the Final Stage 2 DBPR 7-3 7 January 2006
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7.3.1 Selecting Stage 2 DBPR Compliance Monitoring Locations
You should begin the Stage 2 site selection process by calculating the locational running
annual average (LRAA) for each standard monitoring site and Stage 1 DBPR compliance
monitoring site. Note that because the duration for IDSE standard monitoring is one year, the
LRAA for each standard monitoring site is equivalent to the average of all TTHM or HAAS data
collected at the location (either one, four, or six data points depending on your IDSE standard
monitoring frequency). The LRAA for each Stage 1 DBPR compliance monitoring site should
be the LRAA for the year that you conducted standard monitoring (either one or four data points
depending on your Stage 1 compliance monitoring frequency). You should consider using a
spreadsheet to store your data and calculate your LRAAs. You can also use Worksheet 7.2 to
help you organize your data
You must use the site selection protocol in Exhibit 7.7 to select your Stage 2
compliance monitoring locations. The number of required Stage 2 compliance monitoring sites
for your system can be found on page 2 of the Standard Monitoring Requirements -
Attachment sheet in Chapter 2. If you complete all steps in the protocol and need additional
compliance monitoring sites for the Stage 2 DBPR, repeat the protocol until the required number
of sites has been selected. If you arrive at Step 3 or Step 7 and have no more Stage 1 DBPR sites
from which to select, continue to the next step. Example 7.4 shows how a large system uses the
protocol to select their Stage 2 compliance monitoring sites.
You may select alternate sites other than those identified using the protocol, but you
must justify the alternate locations in your IDSE report. Additional factors that may prompt you
to choose alternate sites are discussed below.
Additional Factors to Consider During Selection of Stage 2 Compliance Monitoring Sites
In general, TTHM and HAAS LRAAs are the most important factors in site selection.
However, the Stage 2 rule allows for some flexibility in this process. As you work through the
site selection protocol, you should consider other factors that may lead you to select a site with a
similar or slightly lower LRAA. If you do not use your highest TTHM and HAAS LRAAs to
select your Stage 2 compliance monitoring sites, you must provide justification for your
selection in your IDSE report. The following conditions are possible reasons why you may
select a site with a slightly lower LRAA over another site:
The site provides more complete geographic coverage of the entire distribution
system
• The site allows you to maintain a historical record
Sampling at that site provides the opportunity to collect other water quality or
operational data (e.g., chloramine systems may want to collect nitrate or nitrite data at
that site)
EPA recognizes that a slight difference between LRAAs measured at two sites may not
be meaningful given the normal variability that may occur at a site over time. As a result, the
selection of a Stage 2 compliance monitoring site with a slightly lower LRAA may be acceptable
if other factors, such as those listed above, favor the site with the lower LRAA. Examples 7.5
and 7.6 illustrate situations in which hypothetical systems might select Stage 2 DBPR
compliance monitoring sites using criteria other than the site selection protocol.
It is possible that EPA or your state may not concur with your justification and may
require you to select different Stage 2 compliance monitoring sites.
IDSE Guidance Manual for the Final Stage 2 DBPR ~8 January 2006
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Worksheet 7.2 Stage 2 DBPR Site Selection Worksheet for Standard
Monitoring Page i of i
Instructions:
1) Enter the number of required Stage 2 DBPR compliance monitoring sites based on your
Standard Monitoring Requirements - Attachment summary sheet from Chapter 2.
2) Enter the Site ID and LRAA for each IDSE standard monitoring and Stage 1 compliance
monitoring location. You may want to sort your entries in order by TTHM LRAA or HAAS
LRAA values.
3) As you work through the site selection protocol in Exhibit 7.7, fill in the "Stage 2 Site
Type" column each time you select a site to indicate whether the site is a high TTHM, high
HAAS, Existing Stage 1 DBPR Compliance Monitoring Site, or selected using criteria other
than the protocol.
No. of Stage 2 DBPR Compliance Monitoring Sites Required
Highest TTHM Hiahest HAAS Existina Staae
1 TOTAL
Site ID
Example
LRAA
TTHM (mg/L)
0.075
HAAS (mg/L)
0.045
Stage 2 DBPR Site
Type*
Highest TTHM
* Enter Highest TTHM, Highest HAAS, or existing Stage 1 DBPR
IDSE Guidance Manual for the Final Stage 2 DBPR 7-39
January 2006
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Exhibit 7.7 Protocol for Selecting Stage 2 DBPR (Subpart V)
Compliance Monitoring Sites
Steps1
[required by rule]
1
2
3
4
5
6
7
8
Select the location with the highest TTHM LRAA
Select the remaining location with the highest HAAS
LRAA
For subpart H systems: Select the remaining existing
Stage 1 DBPR average residence time compliance
monitoring location with the highest HAAS LRAA
For ground water systems: Select the remaining
existing Stage 1 DBPR maximum residence time
compliance monitoring location with the highest
HAAS LRAA
Skip this step if you have no more Stage 1 DBPR sites
Select the remaining location with the next highest
TTHM LRAA.
Select the remaining location with the next highest
TTHM LRAA
Select the remaining location with the next highest
HAAS LRAA
For subpart H systems: Select the remaining existing
Stage 1 DBPR average residence time compliance
monitoring location with the highest TTHM LRAA
For ground water systems: Select the remaining
existing Stage 1 DBPR maximum residence time
compliance monitoring location with the highest
TTHM LRAA
Skip this step if you have no more Stage 1 DBPR sites
Select the remaining location with the next highest
HAAS LRAA
Stage 2 Compliance Monitoring
Sites Selected 2
1st highest TTHM site
1st highest HAAS site
1st Stage 1 DBPR site
2nd highest TTHM site
3rd highest TTHM site
2nd highest HAAS site
2nd Stage 1 DBPR site
3rd highest HAAS site
If you need more Stage 2 DBPR compliance monitoring locations, Go back to Step 1 of this
protocol and repeat the steps until you have selected the required number of total sites.
1. All steps are based on your calculated LRAAs for your standard monitoring sites and Stage 1 DBPR compliance
monitoring sites. This means that your existing Stage 1 DBPR sites can be selected in steps other than 3 or 7. Stop
when you reach your required number of Stage 2 DBPR compliance monitoring sites.
2. You cannot select the same site as a highest TTHM and a highest HAAS compliance monitoring site.
IDSE Guidance Manual for the Final Stage 2 DBPR 7-40
January 2006
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E,
A
the IDSE
systems c
Stage 1 D
Requiren
Stage 2 ci
•
•
•
The table
monitorin
xample 7.4 Selecting Stage 2 DBPR Compliance Monitoring Sites
consecutive system serving 15,000 people has conducted standard monitoring for
This system purchases disinfected ground water from a number of ground water
rawing from the same aquifer. Based on state determination, the system has two
BPR compliance monitoring sites. According to the Standard Monitoring
tents Attachment sheet in Chapter 2, the system must select the following four
3mpliance monitoring sites from IDSE standard monitoring and Stage 1 DBPR sites:
2 highest TTHM sites,
1 highest HAAS site, and
1 maximum residence time sites from the existing Stage 1 DBPR data.
below lists the TTHM and HAAS LRAAs for the Stage 1 DBPR compliance
g sites and standard monitoring sites during the IDSE monitoring period.
Site Number and Description
TTHM LRAA (mg/L)
HAAS LRAA (mg/L)
Stage 1 DBPR Compliance Monitoring Results:
1 (Stage 1 max. residence time)
2 (Stage 1 max. residence time)
0.059
0.036
0.037
0.045
IDSE Standard Monitoring Results:
3 (high TTHM)
4 (high TTHM)
5 (high HAAS)
6 (high HAAS)
7 (ave. residence time)
8 (near entry point)
0.058
0.052
0.051
0.047
0.038
0.021
0.031
0.034
0.042
0.038
0.034
0.015
IDSE Guidance Manual for the Final Stage 2 DBPR 7-41
January 2006
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Example 7.4 Selecting Stage 2 DBPR Compliance Monitoring Sites (cont.)
The system used the required protocol in Exhibit 7.7 to select their compliance monitoring
sites.
Go to Step 1: Select the Highest TTHMLRAA Site
Site 1 has the highest TTHM LRAA and is selected as the first high TTHM site.
Go to Step 2: Select the Highest HAAS LRAA Site
Site 2 has the highest HAAS LRAA and has not already been selected. Therefore,
Site 2 is chosen as the first high HAAS site.
Go to Step 3: Select the Stage 1 Maximum Residence Time Site with the Highest HAAS LRAA
There are no remaining Stage 1 sites to select from. Skip this step and go to Step 4.
Go to Step 4: Select the Next Highest TTHMLRAA Site
Site 3 has the next highest TTHM LRAA and is therefore chosen as the next highest
TTHM site.
Go to Step 5: Select the Next Highest TTHMLRAA Site
Site 4 has the next highest TTHM LRAA and is therefore chosen as the next highest
TTHM site.
Final Inventory of Stage 2 DBPR Compliance Monitoring Sites*
Highest TTHM: Site 1, Site 3, Site 4 (3 sites)
Highest HAAS: Site 2(1 site)
Existing Stage 1 DBPR Site (as described in Step 3): No sites
TOTAL Sites = 4
*Note that the requirements on the previous page are for 2 highest TTHM sites, 1 highest
HAAS site, and 1 maximum residence time site from existing Stage 1 DBPR data. However,
because the two Stage 1 DBPR sample sites were the highest TTHM site and the highest
HAAS site, these sites were selected during the first two steps of the selection protocol. As a
result, there were no remaining Stage 1 DBPR sites to choose from during Step 3. Step 3 was
skipped and the remaining two Stage 2 compliance sites were chosen using Steps 4 and 5.
IDSE Guidance Manual for the Final Stage 2 DBPR 7-42 January 2006
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A
sites from
highest T
The fourt
standard i
monitorin
standard i
A
the highe
LRAAth
standard
Example 7.5 Maintaining a Historical Record
ground water system serves 90,000 people and must select four Stage 2 compliance
L standard monitoring and Stage 1 DBPR data. The system has already selected one
THM site, one highest HAAS site, and one Stage 1 maximum residence time site.
i site to be selected is a high TTHM site which must be selected from the IDSE
nonitoring and Stage 1 DBPR sites not yet selected for Stage 2 compliance
g. The table below lists three remaining high-TTHM sites among the IDSE
nonitoring and Stage 1 DBPR sites.
Site Number and Description
4 (Standard monitoring high TTHM)
8 (Standard monitoring high TTHM)
9 (Stage 1 DBPR max residence time site)
LRAA
TTHM (mg/L)
0.072
0.065
0.070
HAAS
(mg/L)
0.051
0.056
0.051
mong the three remaining high TTHM IDSE sites, standard monitoring Site 4 has
st TTHM LRAA. However, the Stage 1 DBPR site has only slightly lower TTHM
an standard monitoring Site 4. The system chooses the Stage 1 DBPR site over
monitoring site 4 for the Stage 2 high TTHM site to maintain the historical DBF
Example 7.6 Providing Geographic Coverage When Choosing Stage 2 Sites
In general, two representative high TTHM sites should not be located in the same
general area of the distribution system. Consider the following example:
The two highest TTHM LRAAs in the
distribution system are from adjacent historical
sample sites (sites A and B). The site with the third
highest TTHM LRAA is on the far side of the
distribution system (site C). In this case, consider
selecting sites A and C or B and C as Stage 2 sites
for a broader geographical coverage of the
distribution system.
Water Treatment Plant
IDSE Guidance Manual for the Final Stage 2 DBPR 7-43
January 2006
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7.3.2 Determining Your Stage 2 DBPR Compliance Monitoring Schedule
The first step in determining your Stage 2 DBPR compliance monitoring schedule is to
select your peak historical month. You should use the peak historical month selected in your
IDSE standard monitoring plan unless new data suggest another month. Refer to Section 7.1.2
for more information on determining peak historical month.
You must conduct Stage 2 DBPR compliance monitoring during the peak historical
month. If you are a ground water system that serves more than 9,999 people or you are a subpart
H system that serves more than 499 people, you must also conduct Stage 2 compliance sampling
at 90 day intervals before and/or after the peak historical month.
The intent of the required time interval is to ensure that samples are representative of the
quality of water over an extended period and do not over-emphasize either high or low
concentrations of TTHM or HAAS that might occur seasonally. For example, a system on
quarterly monitoring could sample in the third full week of every third month. It is not
necessary to sample all sites on the same day.
7.3.3 Preparing the IDSE Report for Standard Monitoring
Every system that conducts IDSE standard monitoring must prepare and submit an IDSE
Report for Standard Monitoring. You should submit the report to the Information Processing and
Management Center (IPMC) for review by EPA or your state. See Section 1.4 of this guidance
manual for information on how to submit your report to the IPMC.
EPA has developed an IDSE Report for Standard Monitoring Form (Form 7),
presented in this section and available electronically as part of the IDSE Tool. You are not
required to use this form; however, if you choose not to use it, refer to Exhibit 7.6 for a list of the
minimum elements you must include in your IDSE report.
The IDSE Tool creates a custom form for your system and provides links A
to technical guidance from this manual. The tool is available on EPA's website at (
http://www.epa.gov/safewater/disinfection/stage2.
IDSE Tool
Before you begin Stage 2 DBPR compliance monitoring, you will also be required to
prepare a Stage 2 DBPR compliance monitoring plan. In addition, if you are a subpart H system
serving >3,300 people, you must submit a copy of your Stage 2 compliance monitoring plan to
the state. If you include compliance calculation procedures in your IDSE report, the report can
meet the requirement of the plan, and you do not have to prepare or submit a separate plan. As a
guide for specifying your compliance calculation procedures, refer to the Stage 1 DBPR,
141.133(b), and your Stage 1 compliance monitoring plan. Check with your state, as they may
have different requirements under the Stage 2 DBPR. If you are a consecutive or wholesale
system, your state may choose to use its special primacy authority to modify your Stage 2
compliance monitoring requirements. In this case, you should check with the state to see if they
IDSE Guidance Manual for the Final Stage 2 DBPR 7-44 January 2006
-------
are going to use this authority. You should develop your IDSE report for the total number of
required Stage 2 compliance locations for your system.
The IDSE report for standard monitoring form includes the following sections:
I. General Information
II. Stage 2 DBPR Requirements
III. Monitoring Results
IV. Justification of Stage 2 DBPR Compliance Monitoring Sites
V. Peak Historical Month and Stage 2 DBPR Compliance Monitoring Schedule
VI. Distribution System Schematic
VII. Attachments
Sections of the form with an asterisk (*) are required by the Stage 2 DBPR. Examples of
completed IDSE reports for standard monitoring using this form are provided in Appendices H
and I of this guidance manual and in the EPA manual, Initial Distribution System Evaluation
Guide for Systems Serving < 10,000 People. The rest of this section provides guidance on the
completion of this form.
I. General Information
LA. PWS Information* - If nothing has changed since you completed your standard
monitoring plan form, copy information from your plan into this section. If your
system characteristics have changed, see Section 7.1.3 of this manual for
guidance on completing this section.
IB. Date Submitted* - Enter either the date that you are submitting the form
electronically, putting it in the mailbox, or dropping it off with an express
delivery service. Be sure to submit your IDSE report before the deadline found
on your requirements summary sheet.
1C. PWS Operations - This section asks questions about your system to help inform
EPA and state personnel during the plan review process. If nothing has changed
since you completed your standard monitoring plan form, copy information from
your plan into this section. If your system characteristics have changed, see
Section 7.1.3 of this manual for guidance on completing this section.
ID. Contact Person* - Enter the contact information of the person who is submitting
the report. This should be the person who will be available to answer questions
from EPA and/or state reviewers.
II. Stage 2 DBPR Requirements*
II. A Number of Compliance Monitoring Sites - Refer to the Standard Monitoring
Requirements - Attachment sheet in Chapter 2. Copy the numbers from the
"Stage 2 Compliance Monitoring Requirements" table that correspond to your
source type and the population served by your system.
IDSE Guidance Manual for the Final Stage 2 DBPR 7-45 January 2006
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II.B. Schedule - This should be the same schedule you entered for your standard
monitoring plan. See Section 7.1.3 of this manual for guidance.
II. C. Compliance Monitoring Frequency - Refer to the Standard Monitoring
Requirements - Attachment in Chapter 2. Locate the monitoring frequency from
the "Stage 2 Compliance Monitoring Requirements" table that corresponds to
your source type and the population served by your system. Put a check mark in
the box corresponding to that monitoring frequency.
III. Monitoring Results*
III. A. Did you deviate in any way from your approved standard monitoring plan? - Put a
check mark in the appropriate box to identify whether your system collected any
standard monitoring samples on different dates or at different locations than
indicated in your approved standard monitoring plan.
If you sampled on a different date or during a different week than scheduled in the
approved monitoring plan, you should write an explanation in the space provided
(or in attached sheets). You should include the standard monitoring site ID, the
scheduled sampling date or week from your monitoring plan, and the actual
sampling date. You must also explain why you sampled on a different day or
week than planned. An example explanation is shown below.
According to our standard monitoring plan, we were to collect samples at
standard monitoring sites 2 and 4 on January 14, 2009. However, a
major snowstorm created hazardous road conditions and limited our
access to sample locations. Therefore, we conducted our sampling at all
sites on January 18, 2009 after the roads were cleared.
III.B. Where were your TTHM and HAAS samples analyzed? - Put a check mark in the
appropriate box to identify whether your system analyzed TTHM and HAAS
samples in an in-house laboratory or sent the samples to a certified laboratory for
analysis.
If you analyzed your TTHM and HAAS samples in an in-house laboratory, check
the appropriate box to identify whether your laboratory is certified. If you sent
your TTHM and HAAS samples to a certified laboratory, enter the name of the
laboratory in the blank. If you used more than one laboratory (e.g., if you used
different laboratories for standard monitoring samples and Stage 1 DBPR
compliance samples), list both laboratories, or check "in-house" and list the name
of the laboratory if applicable.
III.C What method(s) was used to analyze your TTHM and HAAS samples? - Put a
check mark in the appropriate box to indicate the analytical method used to
measure the TTHM and HAAS concentrations of your standard monitoring and
Stage 1 DBPR compliance samples. If more than one method was used (e.g., if
you used different laboratories for standard monitoring samples and Stage 1
IDSE Guidance Manual for the Final Stage 2 DBPR 7-46 January 2006
-------
DBPR compliance samples), check more than one method. If you do not know
what method was used, contact your laboratory.
HID. IDSE Standard Monitoring Results - TTHM - Enter your TTHM results for each
standard monitoring site for each monitoring period in which you collected data.
For each sample result, enter the date on which sampling was conducted. If you
are a subpart H system serving more than 49,999 people or a ground water system
serving more than 499,999 people, you were required to conduct standard
monitoring at more than 8 sites. Therefore, you will need to attach additional
sheets.
III.E. IDSE Standard Monitoring Results - HAAS - Enter your HAAS results for each
standard monitoring site for each monitoring period in which you collected data.
For each sample result, enter the date on which sampling was conducted. If you
are a subpart H system serving more than 49,999 people or a ground water system
serving more than 499,999 people, you were required to conduct standard
monitoring at more than 8 sites. Therefore, you will need to attach additional
sheets.
III.F. Stage 1 DBPR Compliance Monitoring Results - TTHM - Enter your TTHM
results for each Stage 1 site for each monitoring period in which you collected
data. For each sample result, enter the date on which sampling was conducted.
Attach additional sheets if needed.
III.G. Stage 1 DBPR Compliance Monitoring Results - HAAS - Enter your HAAS
results for each Stage 1 site for each monitoring period in which you collected
data. For each sample result, enter the date on which sampling was conducted.
Attach additional sheets if needed.
IV. Justification of Stage 2 DBPR Compliance Monitoring Sites*
Enter the site ID from the distribution schematic and the site type (whether it is
highest TTHM, highest HAAS, Stage 1 DBPR, or a site selected using criteria other
than the site selection protocol). For example:
This site had the 2nd highest TTHM LRAA
An example of how you might justify a site that was not selected using the protocol is
below:
Among the three remaining high TTHM sites, standard monitoring Site 4 has the
highest TTHM LRAA. However, Stage 1 DBPR Site 7 has only a slightly lower
TTHM LRAA than standard monitoring Site 4. Therefore, we choose Stage 1
DBPR Site 7 over standard monitoring site 4 to maintain the historical DBF
record.
IDSE Guidance Manual for the Final Stage 2 DBPR 7-47 January 2006
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V. Peak Historical Month and Proposed Stage 2 DBPR Compliance Monitoring
Schedule
V. A. Peak Historical Month* - Enter the month that you determined to be your peak
historical month.
V.B Is Your Peak Historical Month the Same as in Your IDSE Standard Monitoring
Plan? - Put a check mark in the appropriate box to identify whether your system
used the same peak historical month as in your standard monitoring plan. If your
standard monitoring results prompted you to change your peak historical month,
explain how you selected a new peak historical month.
V.C. Proposed Stage 2 DBPR Compliance Monitoring Schedule* - Enter the ID for
each Stage 2 DBPR compliance monitoring site in the table (these should match
the ID's you enter in Section IV and on your schematic). Enter your proposed
sampling schedule for the number of monitoring periods identified in Section
II.C. The entry can be a specific date or week and can be in a number of different
formats. For example:
7/9/07
2nd week in Nov ' 07
Week of 7/9/07
Remember that at least one monitoring period must be during the peak historical
month identified in Section V.A. Note that there is only space for 8 monitoring
sites on this sheet. If you are a subpart H system serving more than 249,999
people you are required to monitor at more than 8 sites. Therefore, you will need
to attach additional sheets.
VI. Distribution System Schematic* - A distribution system schematic is required only if it
has changed from your approved IDSE standard monitoring plan. If it has changed,
attach the revised distribution system schematic. See Section 7.1.3 of this manual for
guidance.
VII. Attachments - Put a check mark in each of the boxes corresponding to any attachments
that you have included in your report.
A distribution system schematic is required only if it has changed since you submitted
your IDSE standard monitoring plan. Refer to Section VI for details.
If you submit your IDSE report electronically, you also have the option to submit
attachments in hard copy. Include a note in your electronic IDSE report explaining that
attachments are being submitted in hard copy, and mail the hard copy to the IPMC
mailing address in your Requirements Summary Sheet. The IPMC will match the hard
copy submission with your electronic submission when it is received.
If you are a subpart H system serving >3,300 people, you must submit a copy of your
Stage 2 compliance monitoring plan to the state. If you include compliance calculation
IDSE Guidance Manual for the Final Stage 2 DBPR ~8 January 2006
-------
procedures in your IDSE report, the report can meet the requirement of the plan, and you
do not have to prepare or submit a separate plan. As a guide for specifying your
compliance calculation procedures, refer to the Stage 1 DBPR, 141.133(b), and your
Stage 1 compliance monitoring plan. Check with your state, as they may have different
requirements under the Stage 2 DBPR.
Enter the total number of pages in your IDSE report (including attachments) in the blank
at the bottom of this section. This will allow EPA or your state to ensure that all pages
were received.
IDSE Guidance Manual for the Final Stage 2 DBPR 7-49 January 2006
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This page intentionally left blank.
IDSE Guidance Manual for the Final Stage 2 DBPR 7-50 January 2006
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Form 7: IDSE Report for Standard Monitoring Page 1 of 9
I. GENERAL INFORMATION
A. PWS Information*
PWSID:
| B. Date Submitted*
PWS Name:
PWS Address:
City:
Population Served
System Type: S
news [
D NTNCWS [
State: Zip:
ource Water Type:
D Subpart H
D Ground
C. PWS Operations
Residual Disinfectant Type: n Chlorine n Ch
Number of Disinfected Sources: Surface
Buying / Selling Relationships:
n Consecutive System
n Wholesale System
n Neither
iloramines n Other:
GWUDI Ground Purchased
D. Contact Person*
Name:
Title:
Phone #:
Fax#:
E-mail:
II. STAGE 2 DBPR REQUIREMENTS*
A. Number of
Compliance Monitoring
Sites
Highest TTHM:
Highest HAAS:
Existing Stage 1:
Total:
B. Schedule C
n Schedule 1
n Schedule 2
n Schedule 3
n Schedule 4
Compliance Monitoring Frequency
n During peak historical month
(1 monitoring period)
n Every 90 days (4 monitoring periods)
IDSE Guidance Manual for the Final Stage 2 DBPR 7-51
January 2006
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Form 7: IDSE Report for Standard Monitoring Page2of9
I. MONITORING RESULTS*
A. Did you deviate in any way from your approved standard D Yes n No
monitoring plan?
If YES, explain (attach additional pages if necessary):
B. Where were your TTHM and HAAS samples analyzed?
n In-House
Is your in-house laboratory certified? D Yes n No
n Certified Laboratory
Name of certified laboratory:
C. What method(s) was used to analyze your TTHM and HAAS
samples?
TTHM HAAS
D EPA 502.2 D EPA 552.1
D EPA 524.2 D EPA 552.2
D EPA 551.1 D EPA 552.3
D SM 6251 B
IDSE Guidance Manual for the Final Stage 2 DBPR 7-52 January 2006
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Form 7: IDSE Report for Standard Monitoring page 3 of 9
III. MONITORING RESULTS (Continued)*
D. 1C
)SE Standard Monitoring Results - TTHM
Site ID1
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
TTHM (mg/L)
LRAA
1 Verify that site IDs for IDSE standard monitoring sites match the site IDs in your Standard Monitoring Plan.
Attach additional sheets as needed for IDSE standard monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
7-53
January 2006
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Form 7: IDSE Report for Standard Monitoring page 4 of 9
III. MONITORING RESULTS (Continued)*
E. 1C
)SE Standard Monitoring Results - HAAS
Site ID1
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
HAAS (mg/L)
LRAA
1 Verify that site IDs for IDSE standard monitoring sites match the site IDs in your Standard Monitoring Plan.
Attach additional sheets as needed for IDSE standard monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
7-54
January 2006
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Form 7: IDSE Report for Standard Monitoring page 5 of 9
III. MONITORING RESULTS (Continued)*
F. Sis
ige 1 DBPR Compliance Monitoring Results - TTHM
Site ID1
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
TTHM (mg/L)
LRAA
1 Verify that site IDs for Stage 1 compliance monitoring sites match the site IDs in your Standard Monitoring Plan.
Attach additional sheets as needed for Stage 1 compliance monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
7-55
January 2006
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Form 7: IDSE Report for Standard Monitoring page e of 9
III. MONITORING RESULTS (Continued)*
G. Sti
age 1 DBPR Compliance Monitoring Results - HAAS
Site ID1
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
HAAS (mg/L)
LRAA
1 Verify that site IDs for Stage 1 compliance monitoring sites match the site IDs in your Standard Monitoring Plan.
Attach additional sheets as needed for Stage 1 compliance monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
7-56
January 2006
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Form 7: IDSE Report for Standard Monitoring page7of9
IV. JUSTIFICATION OF STAGE 2 DBPR COMPLIANCE MONITORING SITES*
Stage 2
Compliance
Monitoring
Site ID
Site Type
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
Justification
Attach additional copies of this sheet if you need more room.
IDSE Guidance Manual for the Final Stage 2 DBPR 7-5 7
January 2006
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Form 7: IDSE Report for Standard Monitoring Page s of 9
V. PEAK HISTORICAL MONTH AND PROPOSED STAGE 2 DBPR COMPLIANCE
MONITORING SCHEDULE
A.
B.
Peak Historical Month*
Is Your Peak Historical Month the Same as in Your IDSE Standard
Monitoring Plan?
DYes
D No
If no, explain how you selected your new peak historical month (attach
additional sheets if needed)
C. Proposed Stage 2 DBPR Compliance Monitoring Schedule*
Stage 2
Compliance
Monitoring
Site ID
Projected Sampling Date (date or week)1
period 1
period 2
period 3
period 4
1 period = monitoring period. Complete for the number of monitoring periods from
Section II. C.
Attach additional copies of this sheet if you need more room.
IDSE Guidance Manual for the Final Stage 2 DBPR 7-58
January 2006
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Form 7: IDSE Report for Standard Monitoring Page 9 of 9
VI. DISTRIBUTION SYSTEM SCHEMATIC*
ATTACH a schematic of your distribution system if it has changed since you submitted
your Standard Monitoring Plan (Form 6).
VII. ATTACHMENTS
D Additional sheets for explaining how and why you deviated from your standard
monitoring plan (Section III).
D Additional sheets for Standard Monitoring Results (Section III). REQUIRED if you are
a subpart H system serving more than 49,999 people or a ground water system
serving more than 499,999 people.
D Additional sheets for Stage 2 DBPR Compliance Monitoring Sites (Section IV).
REQUIRED if you are a subpart H system serving more than 249,999 people.
D Additional sheets for explaining how you selected the peak historical month (Section
V).
D Additional sheets for proposed Stage 2 DBPR peak historical month and compliance
monitoring schedule (Section V). REQUIRED if you are a subpart H system serving
more than 249,999 people.
D Distribution system schematic* (Section VI). REQUIRED if it has changed from
your approved IDSE standard monitoring plan.
D Compliance calculation procedures (for Stage 2 Compliance Monitoring Plan).
Total Number of Pages in Your Report:
Note: Fields with an asterisk (*) are required by the Stage 2 DBPR
IDSE Guidance Manual for the Final Stage 2 DBPR 7-59 January 2006
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IDSE Guidance Manual for the Final Stage 2 DBPR 7-60 January 2006
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7.4 Recordkeeping
The IDSE standard monitoring report must be kept on file for
10 years after the date it is submitted. If EPA or your state
modifies the recommendations made in your report or approves
alternative Stage 2 DBPR compliance monitoring locations, you
must also keep a copy of EPA or your state's notification on file
for 10 years after the date of the notification. You must make
your IDSE report and any notification available for review by
your state or the public.
The standard monitoring plan, including any modifications by
EPA or your state, must also be kept on file for as long as you are
required to retain your IDSE standard monitoring report. You
must make the plan and any modifications available for review by
your state or the public.
7.5 Next Steps: Preparing the Stage 2 DBPR Compliance Monitoring Plan
As the final step before you can begin compliance monitoring for the Stage 2 DBPR, you
must develop and implement a Stage 2 DBPR monitoring plan by the deadline provided in
your requirements summary sheet. The plan will be similar to your Stage 1 DBPR monitoring
plan in that it will identify how you intend to sample for compliance with Stage 2. You must
keep your plan on file for state and public review. If you are a subpart H system serving >
3,300 people, you must submit your plan to EPA or your state prior to when you are required to
start monitoring.
Exhibit 7.8 contains the minimum requirements for what must be included in your Stage 2
DBPR compliance monitoring plan. Because compliance monitoring plans are not addressed as
part of the IDSE provisions of the Stage 2 DBPR, EPA has not included detailed guidance for
developing Stage 2 compliance monitoring plans in this guidance manual. EPA plans to
develop other manuals and training that address the compliance monitoring provisions of the
Stage 2 DBPR.
See EPA's website http://www.epa.gov/safewater/disinfection/stage2 for an up-to-date
inventory of Stage 2 DBPR guidance manuals and training materials, or call the Safe Drinking
Water Hotline at 1-800-426-4791.
IDSE Guidance Manual for the Final Stage 2 DBPR 7-61
January 2006
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Exhibit 7.8 Required Contents of Stage 2 DBPR Compliance Monitoring Plans
All Systems
Additional Requirements for Consecutive and
Wholesale Systems l
Monitoring locations
Monitoring dates
Compliance calculation
procedures
If your state has used its special primacy
authority to modify your monitoring
requirements, you must include monitoring plans
for other systems in your combined distribution
system
1. See Appendix D of this manual for guidance specifically for consecutive and wholesale systems
References
T.M. Walski, D.V. Chase, D.A. Savic, W. Grayman, S. Beckwith, E. Koelle. 2003. "Advanced Water
Distribution Modeling and Management", Haestad Methods, Waterbury CT: Haestad Press.
IDSE Guidance Manual for the Final Stage 2 DBPR 7-62
January 2006
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Appendix A
Formation of Disinfection Byproducts
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A.I Introduction
The formation of disinfection byproducts (DBFs) is a function of many factors,
including:
• precursor concentration,
• disinfectant dose,
• water pH,
• temperature,
contact time, and
• bromide ion concentration.
The purpose of this appendix is to provide a brief summary of the factors that affect DBF
formation in water treatment processes and distribution systems. More detailed information on
this subject can be found in other existing literature, including the following EPA guidance
documents:
• Enhanced Coagulation and Enhanced Precipitative Softening Guidance Manual,
available from EPA (Document #815-R-99-012)
• Controlling Disinfection By-Products andMicrobial Contaminants in Drinking
Water, available from EPA (Document #600-R-01-110)
• Alternative Disinfectants and Oxidants Guidance Manual, available from EPA
(Document #815-R-99-014)
• Microbial and Disinfection Byproduct Rules: Final Simultaneous Compliance
Guidance Manual, available from EPA (Document #)
Moreover, it should be noted that the book entitled Formation and Control of
Disinfection By-Products in Drinking Water (Singer et al., 1999) contains a detailed compilation
of the chemistry of DBF formation in Chapter 3 (Krasner, 1999). The references for that chapter
represent the seminal works in the literature. Additional references are also presented in the
following discussion.
A.2 Formation of DBFs
Organic DBFs (and oxidation byproducts) are formed by the reaction between organic
substances, inorganic compounds such as bromide, and oxidizing agents that are added to water
during treatment. In most water sources, natural organic matter (NOM) is the major constituent
of organic substances and DBF precursors. Total organic carbon (TOC) is typically used as a
surrogate measure for precursor levels and is used in the Stage 1 DBPR to determine precursor
removal compliance. Dissolved organic carbon (DOC) and UV absorption at 254 nm [UV254] are
also often used as surrogate parameters for monitoring precursor levels. The following are the
major factors affecting the type and amount of DBFs formed.
IDSE Guidance Manual for the Final Stage 2 DBPR ~ January 2006
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• Type of disinfectant, dose, and residual concentration
Concentration and characteristics of precursors
• Water temperature
• Water chemistry (including pH, bromide ion concentration, organic nitrogen
concentration, and presence of other reducing agents such as iron and manganese)
• Contact time and mixing conditions for disinfectant (oxidant), coagulant, source
water, and other treatment chemicals
A summary for each of these factors follows.
A.2.1 Impact of Disinfection Method on Organic DBF Formation
Organic DBFs can be subdivided into halogenated and non-halogenated byproducts.
Halogenated organic disinfection byproducts are formed when organic and inorganic compounds
found in water react with free chlorine, free bromine, or free iodine. The formation reactions
may take place in the treatment plant and the distribution system. Free chlorine can be
introduced to water directly as a primary or secondary disinfectant, or as a byproduct of the use
of chlorine dioxide and chloramines.
Reactions between precursors, bromide and iodide ions, and chlorine lead to the
formation of a variety of halogenated DBFs including THMs and HAAs. The presence of
bromide can affect both the rate and the yield of DBFs, and if the ratio of bromide to precursors
(measured as TOC) increases, the percentage of brominated DBFs also increases (Krasner, 1999
and references therein). Similarly, the presence of iodide may result in the formation of mixed
chlorobromoiodomethanes byproducts (Bichsel and Von Gunten, 2000).
The following is an overview of disinfectants including chlorine, chloramines, chlorine
dioxide, ultraviolet (UV) irradiation, and ozone and their potential impacts on the formation of
THMs and HAAs. Some discussion is also included of potential issues associated with the use
of these disinfectants.
Chlorine
Most water systems that disinfect use either liquid or gaseous chlorine as their
disinfectant. Halogenated byproducts are formed when free chlorine reacts with natural organic
matter. In addition, brominated byproducts are formed when source water containing bromide is
chlorinated. Chlorine reacts with natural organic matter in the water to form THMs, HAAs and
other disinfection byproducts.
IDSE Guidance Manual for the Final Stage 2 DBPR A-2 January 2006
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Water systems using chlorine can modify their treatment to reduce TTHM and HAAS
concentrations in the finished water. Treatment modifications include moving the point of
chlorination downstream in the water treatment plant, optimizing coagulation to enhance
removal of DBF precursors, and using another disinfectant or oxidant to supplement or replace
the use of free chlorine. Moving the point of chlorination downstream in the treatment train
allows the concentration of disinfection byproduct precursors to be reduced before chlorine is
added and may be implemented seasonally. Systems that are required to develop a disinfection
profile must calculate a disinfection benchmark for the treatment configuration in place before
making any changes to their disinfection practices.
Chloramines
Studies have documented that chloramines produce significantly lower THM and HAA
levels than free chlorine, and there is no clear evidence that the reaction of precursors and
chloramine leads to the formation of THMs (Singer and Reckhow, 1999; USEPA, 1999).
Predictions of an empirical DBF formation model calibrated using ICR data indicated that under
chloraminated conditions, THMs and HAAs are formed in full-scale plants and distribution
systems at a fraction of the amount that would be expected based on observations of DBF
formation under free chlorine conditions. The amount of formation with chloramines varied
from 5% to 35% of that calculated for free chlorine, depending on the individual DBF species
(Swanson et al., 2001). When chloramination is used, it is possible that DBFs might form if
chlorine is added before ammonia. If the mixing process is inefficient, it is also possible that
DBFs might form during the mixing of chlorine and ammonia. In this case, free chlorine might
react with precursors before the complete formation of chloramines. In addition,
monochloramine slowly hydrolyzes to release free chlorine in water. This free chlorine may
contribute to the formation of small amounts of additional DBFs in the distribution system.
Additional issues should be considered prior to switching to chloramination. For
example, systems using chloramines that have excess ammonia, warm temperatures, long
distribution system residence times, and low chloramine residuals may experience nitrification in
their distribution systems. Also, systems should be aware that switching from chlorine to
chloramines in the distribution system can also change the oxidation reduction potential of the
water. The Microbial and Disinfection Byproduct Rules: Final Simultaneous Compliance
Guidance Manual includes a detailed discussion of factors to consider prior to switching to
chloramines.
Chlorine Dioxide
The application of chlorine dioxide does not produce significant amounts of THMs and
HAAs unless chlorine is formed as an impurity in the generation process. However, THMs and
HAAs will form if excess chlorine is added to water to ensure complete reaction with sodium
chlorite during the production of chlorine dioxide.
Chlorine dioxide can also oxidize bromide ions to bromine. The bromine can then react
with organic matter to form brominated DBFs. Systems with high bromide concentrations that
are near the Stage 2 DBPR limits for THMs or HAAS should take this into account.
IDSE Guidance Manual for the Final Stage 2 DBPR ~ January 2006
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When chlorine dioxide is used as a disinfectant, chlorite is formed. The MCL for chlorite
was set at 1.0 mg/L by the Stage 1 D/DBPR. Systems using chlorine dioxide must monitor daily
at the entrance to the distribution system for chlorite. They must also collect 3 chlorite samples
per month in the distribution system. As much as 70 percent of the chlorine dioxide added to
water can break down to form chlorite. This limits the dose of chlorine dioxide that can be used
and therefore the amount of inactivation that can be achieved.
Chlorite can react with excess chlorine to reform chlorine dioxide. Some systems may
opt to boost with chlorine to maintain a residual in the distribution system. Systems that use
chlorine dioxide and then boost with chlorine in the distribution system are required by the Stage
1 D/DBPR to monitor the chlorine dioxide residual in the distribution system. If doses are high
enough, systems could exceed either the chlorine dioxide MRDL or the chlorite MCL.
Reformed chlorine dioxide can also volatilize at consumer's taps and react with volatile organics
to cause odor problems.
Ultraviolet Irradiation
To date, there is no evidence to suggest that ultraviolet irradiation results in the formation
of any disinfection byproducts; however, little research has been performed in this area. Most of
the research regarding application of UV and DBF formation has focused on chlorinated DBF
formation as a result of UV application prior to the addition of chlorine or chloramines (Malley
et al., 1995). Studies comparing the effects of UV light followed by chlorination versus
chloramination suggest UV does not affect DBF formation in either of these two cases (Malley et
al., 1995).
A main drawback with UV is the possibility of microbes passing through at times the
lamp is operating off specification. At low UV intensities, some microbes have shown the
ability to repair damage done by UV light. Because of this, even drops in lamp intensity not
enough to cause a violation of disinfection requirements may allow microbes into the
distribution system where they can repair themselves, colonize biofilms, and cause problems
with TCR compliance. Therefore any periods of the lamp operating off specification should be
minimized.
Because UV disinfection relies on UV light interacting with the organism's genetic
material to be effective, any substance that either absorbs or refracts the UV light can interfere
with disinfection. Compounds with the potential to do this include dissolved organic carbon
(DOC), iron, manganese, calcium, aluminum, and ozone. EPA has developed an Ultraviolet
Disinfection Guidance Manual that discusses these issues in detail.
IDSE Guidance Manual for the Final Stage 2 DBPR A-4 January 2006
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Ozone
Ozone does not directly produce chlorinated DBFs. However, if chlorine is added before
or after ozonation, mixed bromo-chloro DBFs as well as chlorinated DBFs can form. Ozone can
alter the characteristics of precursors and affect the concentration and speciation of halogenated
DBFs (THMs and HAAs) when chlorine is subsequently added downstream. In waters with
bromide concentrations, ozonation can lead to the formation of bromate and other brominated
DBFs. Bromate, like TTHM and HAAS, is a regulated DBF.
Ozonation of natural waters also produces aldehydes, haloketones, ketoacids, carboxylic
acids, and other types of biodegradable organic material. The biodegradable fraction of organic
material can serve as a nutrient source for microorganisms, and should be removed to prevent
microbial regrowth in the distribution system. AOC is a measure of the organic carbon readily
available as food for microorganisms. Some systems that have added ozone without biological
filtration have experienced increased AOC and microbial growth in the distribution system.
Increased biological growth in the distribution system may result in increased corrosion, taste
and odor problems, as well as potential health risk.
A.2.2 Disinfectant Dose
As the concentration of chlorine or chloramines increases, the production of DBFs
increases. Formation reactions continue as long as precursors and disinfectant are present
(Krasner, 1999 and references therein).
In general, the impact of chlorine concentration is greater during primary disinfection
than during secondary disinfection. The amount of chlorine added during primary disinfection is
usually less than the long-term demand, therefore, the concentration of chlorine is often
insufficient to react with all DBF precursors in the water. On the contrary, during secondary
disinfection, DBF formation is often limited by the concentration of DBF precursors since excess
disinfectant is added to the water to maintain a residual concentration in the distribution system
(Singer and Reckhow, 1999).
Distribution system
In distribution systems, DBF formation reactions can become limited by the disinfectant
concentration when the free chlorine residual drops to low levels. As a rule of thumb, Singer
and Reckhow (1999) suggest this event takes place when the chlorine concentration drops below
approximately 0.3 mg/L.
In many systems booster disinfection is applied to raise disinfectant residual
concentration, especially in remote areas of the distribution system or near storage tanks where
water age may be high and disinfectant residuals can be low. The additional chlorine dose
applied to the water at these booster facilities may increase THM and HAA levels. Further,
booster chlorination can maintain high HAA concentrations because the increased disinfection
residuals can prevent the biodegradation of HAAs. However, booster chlorination can also be
IDSE Guidance Manual for the Final Stage 2 DBPR ~January 2006
-------
useful in decreasing DBF levels by reducing the concentration of secondary disinfectant needed
in the finished water leaving the plant.
A.2.3 Time Dependency of DBF Formation
The longer the contact time between disinfectant/oxidant and precursors, the greater the
amount of DBFs that can be formed. Generally, DBFs continue to form in drinking water as
long as a disinfectant residual and precursors are present. After formation, THMs and HAAs are
generally chemically stable as long as a significant disinfectant residual is still present (Singer
and Reckhow, 1999). As a consequence, high concentrations of DBFs can accumulate in water
with old age.
High THM levels usually occur where the water age is the oldest. Conversely, HAAs
cannot be consistently related to water age because HAAs are known to biodegrade over time
when the disinfectant residual is low. This might result in relatively low HAAs concentrations in
areas of the distribution system where disinfectant residuals are depleted.
A.2.4 Concentration and Characteristics of Precursors
The formation of THMs and HAAs is related to the concentration of precursors at the
point of disinfection. In general, greater DBF levels are formed in waters with higher
concentrations of precursors. Therefore, removing DBF precursors prior to disinfectant addition
is one of the most effective approaches to DBF control.
Studies conducted with different fractions of NOM have indicated the reaction between
disinfectant and NOM with high aromatic content tends to form higher DBF levels than NOM
with low aromatic content. For this reason, UV254, which is generally linked to the aromatic and
unsaturated components of NOM, is considered a good predictor of the tendency of a source
water to form THMs and HAAs (Owen et al., 1998; Singer and Reckhow, 1999).
Specific ultraviolet light absorbance (SUVA) is also often used to characterize
aromaticity and molecular weight distribution of NOM. This parameter is defined as the ratio
between UV254 and the dissolved organic carbon (DOC) concentration of water (Letterman et al.,
1999). It should be noted that the more highly aromatic precursors in source waters,
characterized by high UV254, are more easily removed by coagulation. Thus, it is the UV254
measurement immediately upstream of the point(s) of disinfection within a treatment plant that is
more directly related to THM and HAA formation potential.
IDSE Guidance Manual for the Final Stage 2 DBPR A-6 January 2006
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A.2.5 Water Temperature
The rate of formation of THMs and HAAs increases with increasing temperature.
Consequently, the highest THM and HAA levels may occur in the warm summer months.
However, water demands are often higher during these months, resulting in lower water age
within the distribution system which helps to control DBF formation. Furthermore, high
temperature conditions in the distribution system promote the accelerated depletion of residual
chlorine, which can mitigate DBF formation and promote biodegradation of HAAs unless
chlorine dosages are increased to maintain high residuals (Singer and Reckhow, 1999). For
these reasons, depending on the specific system, the highest THM and HAA levels may be
observed during months which are warm, but not necessarily the warmest. Higher DBF
precursor levels in the fall or spring may also cause the highest THM and HAA levels to be
observed in cooler months.
Seasonal trends affect THM and HAA concentrations differently. For example, when
water is colder, microbial activity is typically lower and DBF formation reactions are slower.
Under these conditions, the highest THM and HAA concentrations might appear in the oldest
water in the system. In warmer water, the highest HAA concentrations might appear in fresher
water, which is likely to contain higher disinfectant residuals that can prevent the biodegradation
of HAAs.
A.2.6 Water pH
In the presence of DBF precursors and chlorine, THM formation increases with
increasing pH, whereas the formation of HAAs decreases with increasing pH. The increased
THM production at high pH is likely promoted by base hydrolysis (favored at high pH). HAAs
are not sensitive to base hydrolysis but their precursors are. Consequently, pH can alter their
formation pathways, leading to decreased production with increasing pH (Singer and Reckhow,
1999).
Water pH also affects the balance of hypobromite and hypobromous acid formation
during the ozonation of waters containing significant concentrations of bromides. At low pH,
the equilibrium shifts to the less reactive hypobromous acid. Consequently, the overall
formation of bromate decrease as the pH decreases (Singer and Reckhow, 1999). However, the
hypobromous acid at low pH can react with NOM to form HAAs and THMs. This may occur if
systems using ozone operate at low pH to control bromate formation. In addition, systems may
maintain a low pH to achieve the required inactivation.
IDSE Guidance Manual for the Final Stage 2 DBPR A-7 January 2006
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A.3 References
Bichsel, Y., and Von Gunten U., 2000. Environmental Science and Technology, 34 (13): 2784.
Krasner S. W., 1999. Chemistry of disinfection by-product formation. In Formation and Control
of Disinfection By-products in Drinking Water. Singer, P.C. (editor). American Water Works
Association, Denver, CO.
Letterman, R.D., A. Amirtharajah, and C.R. O'Melia. 1999. Coagulation and flocculation. In
Water quality and treatment. 5th edition. Letterman R.D. technical editor, American Water
Works Association, McGraw-Hill, New York, NY.
Malley, J.P., J.P. Shaw, and J.D. Ropp. 1995. Evaluation of by-products produced by treatment
ofgroundwaters with ultraviolet irradiation. AWWA Research Foundation Report No. 90685.
Denver CO.
Owen et al., 1998. Removal of DBF precursors by GAC adsorption. AWWA Research
Foundation Report No. 90744. Denver CO.
Singer, P.C., ed. 1999. Formation and Control of Disinfection By-Products in Drinking Water.
American Water Works Association, Denver, CO.
Singer, P.C. andD.A. Reckhow. 1999. Chemical oxidation. In Water quality and treatment. 5th
edition. Letterman R.D. technical editor, American Water Works Association, McGraw-Hill,
New York, NY.
R. Song et al. 1997. Bromate Minimization During Ozonation. Journal American Water Works
Association. 89(6):69.
Swanson, W.J., Z. Chowdhury, R. Summers, and G. Solarik. 2001. Predicting DBFs at full-scale:
calibration and validation of the Water Treatment Plant Model using ICR data. Conference
proceedings, 2001 AWWA Annual Conference, Washington, DC.
USEPA. 1999. Alternative disinfectants and oxidants guidance manual. EPA 815-R-99-014.
IDSE Guidance Manual for the Final Stage 2 DBPR A-8 January 2006
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Appendix B
Stage 2 DBPR and LT2ESWTR Compliance Schedule
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Exhibit B.1 Stage 2 DBPR and LT2ESWTR Compliance Schedule
Schedule 1
Systems serving
> 100,000 people1
Schedule 2
Systems serving
50,000 to 99,999 people1
Schedule 3
Systems serving
10,000 to 49,999 people1
Schedule 4
Systems serving
< 10,000 people1
2006
2007
2008
| LT2 Crypto monitoring
t
IDSE Plan Di
October 1 , 2C
IDJ
Ap
2006
| IDSE mon.
je
106
L
IDSE
Janua
2009
Rep
ry 1
| LT2 Crypto monitoring
t
3E Plan Due
ril 1,2007
IDSE Plar
October 1
IDJ
Ap
2007
IDSE
mon.
LT2
i Due
,2007
3E Plan D
ril 1,2008
IDJ
Jul
Crypto
IDSE
2010
Treatment
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t
BERep
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a
2011
2012 | 2013
J
2014
I 1
Installation | Possible Extension |
i i
ort
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gin Compliance
111,2012 I
Treatment Installation . Possible Extension
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mon.
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1 1
Du
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mon.2]
t
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npliance
,2013
Treatment Installation2 1 Possible Extension 1
1 1
IDSE Report
July 1,2010
2010
Due
2011
2012
T
Begin Cor
October 1
2013
npliance2
,2013
2014
2015
Includes systems that are part of a combined distribution system in which the largest system serves this population.
2 Subpart H systems serving fewer than 10,000 that must conduct Crypto monitoring can sample twice a month for 12 months or
monthly for 24 months. These systems have an additional 12 months to comply with Stage 2 DBPR MCLs and the LT2ESWTR.
IDSE Guidance Manual for the Final Stage 2 DBPR
B-l
January 2006
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IDSE Guidance Manual for the Final Stage 2 DBPR B-2 January 2006
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Appendix C
TTHM and HAAS Sampling Protocol
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C.I Introduction
It is important that TTHM and HAAS samples are properly collected and analyzed to
ensure accurate analytical results. For example, THMs are volatile chemicals, meaning they can
move from the liquid phase to the gas phase under ambient conditions. Therefore, care must be
taken to make sure that no air bubbles are present in the filled sample vial. This appendix
summarizes information on proper sample collection, handling, and laboratory analytical
techniques.
C.2 Analytical Methods
Exhibit C. 1 lists the analytes that are included in TTHM and HAA analyses.
Exhibit C.1 TTHM and HAA Analytes
Analyte Group Code
Analytes in Group
(Abbreviation for Analyte)
HAAS
Haloacetic acids:
Dibromoacetic acid (DBAA)
Dichloroacetic acid (DCAA)
Monobromoacetic acid (MBAA)
Monochloroacetic acid (MCAA)
Trichloroacetic acid (TCAA)
HAA9
HAAS plus four additional analytes
Bromochloroacetic acid (BCAA)
Bromodichloroacetic acid (BDCAA)
Chlorodibromoacetic acid (CDBAA)
Tribromoacetic acid (TBAA)
TTHM
Trihalomethanes:
Bromodichloromethane (BDCM)
Bromoform (CHBrS)
Chloroform (CHC13)
Dibromochloromethane (DBCM)
Exhibit C.2 lists the approved laboratory analytical methods for TTHM and HAAS along
with guidelines for sample collection and storage. These guidelines include type of sample
container, preservative and dechlorinating agents, pH, and sample collection.
IDSE Guidance Manual for the Final Stage 2 DBPR C-l
January 2006
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Exhibit C.2 Sampling Requirements of TTHM and HAAS Analyses
Analyte
Group
TTHM
HAAS
Analytical
Method1
EPA 502.2
EPA 524.2
EPA 551.1
EPA 552.1
EPA 552.2
EPA 552. 34
SM 6251 B
Sample Container
Material2
40 ml_ -120 ml_ screw
cap glass vials with
PTFE-faced silicone
septum
40 ml_ -120 ml_ screw
cap glass vials with
Teflon-faced silicone
septum
60 ml_ screw cap glass
vials with PTFE-faced
silicone septum
250 ml_ (approx.) amber
glass bottles fitted with
Teflon-lined screw caps
50 ml_ (approx.) amber
glass bottles fitted with
Teflon-lined screw caps
50 ml_ (approx.) amber
glass bottles fitted with
Teflon-lined screw caps
40 ml_ or 60 ml_ screw
cap glass vials with
PTFE-faced silicone
septum
Preservative/Dechlorinating Agent
(Recommended amount)
Options:
(1) 3 mg Na2S2O3/40 ml_ sample or
(2) 3 mg Na2S2O3/40 ml_ sample and immediate
acidification using HCI to pH < 2 or
(3) 25 mg ascorbic acid/40 ml_ sample and
immediate acidification using HCI to pH < 2.
Option 1 may be used if THMs are the only
compounds being determined in the sample.
Options 2 & 3 require the sample to be dechlorinated
prior to the addition of acid.
1 g phosphate buffer & NH4CI or Na2SO3 mixture per
60 ml_ sample (mixture consists of 1 part Na2HPO4,
99 parts KH2PO4, and 0.6 parts NH4CI or Na2SO3.
1g per 60 ml_ results in a pH of 4.8-5.5 and 0.1 mg
NH4CI or Na2SO3 per ml_ of sample.)
0.1 mg NH4CI per ml_ of sample
65 mg NH4CI
Storage
Guidelines
Keep at 4°C.
14 days
maximum
hold time3.
Sample Collection Guidelines
Fill bottle to just overflowing but
do not flush out preservatives.
No air bubbles.
Do not overfill.
Seal sample vials with no head
space.
If ascorbic acid is used to
dechlorinate TTHM samples, then
the samples MUST be acidified.
Acidification of TTHM samples
containing Na2S2O3 is required if
the samples will also be analyzed
for VOCs. In both cases, the pH
must be adjusted at the time of
sample collection, not later at the
laboratory.
1(40CFR 141.131 (b))
2 Selection of container should be coordinated with the laboratory.
3 The holding time has been changed to 14 days for all HAAS samples as a part of the Stage 2 DBPR.
4 EPA Method 552.3 has been added as an approved HAAS method as part of the Stage 2 DBPR.
IDSE Guidance Manual for the Stage 2 DBPR
C-2
January 2006
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C.2.1 Sampling Procedure
It is important to follow sampling procedures provided by your certified laboratory.
Sampling procedures may vary slightly among individual laboratories; you should contact your
laboratory to learn their procedures. The following is a common procedure for collecting
samples for TTHM and HAAS analyses.
You will need:
1) Sample vials provided by laboratory (most laboratories will provide sample vials with
proper preservative and dechlorinating agents)
2) Small bottle of 1:1 hydrochloric acid and eye dropper or pasteur pipette (pH
adjustment is necessary for some TTHM methods) (many laboratories will provide
ampules with acid for pH adjustment)
3) Water proof labels and permanent (indelible ink) marker
4) Ice/coolant and cooler
Procedure:
1) Label each sample vial. Use waterproof labels and indelible ink. Each label should
include:
• Unique sample ID
System name
Sample location
• Sample date and time
• Analysis required, if not already on label
2) Remove the aerator from the tap, if there is one present.
3) Open the water tap and allow the system to flush until the water temperature has
stabilized (usually about 3-5 minutes). The purpose of this step is to ensure the
sample does not represent stagnant water that has set for a long time in the water line
between the street and the faucet. The sample should be representative of the water
flowing through the distribution system at the chosen sampling point.
4) Adjust the flow so that no air bubbles are visually detected in the flowing stream.
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5) Slowly fill the sample vial almost to the top without overflowing. Use the bottle cap
to add a small amount of additional sample water while simultaneously capping the
vial to achieve a headspace-free sample. Be careful not to rinse out any of the
preservative/dechlorinating agent during this process. After the bottle is filled, invert
three or four times.
6) If collecting TTHM samples that require acidification, let the sample set for about 1
minute, allowing the dechlorinating chemical to take effect. Carefully open the vial
and adjust the pH of the TTHM sample to < 2 by adding approximately 4 drops of
hydrochloric acid for every 40 mL of sample (amount of acid needed will depend on
buffering capacity of sample). Recap the vial, and invert three or four times.
7) Invert the vial and tap it to check for air bubbles. If bubbles are detected, carefully
open the vial and add more sample water using the cap to achieve a headspace-free
sample.
8) Immediately cool the samples to 4°C by placing them in a cooler with frozen
refrigerant packs or ice, or in a refrigerator. Samples should be maintained at this
temperature during shipment to the laboratory.
9) Complete the Sample Chain of Custody provided by the laboratory and include it
with the sample shipment.
C.2.2 Regarding Loss of Samples
Samples may be "lost" due to a number of reasons:
• Bottle broken during shipment from the water system to the laboratory
• Sample improperly collected (e.g., sample bottle not completely filled)
• Sample improperly shipped (e.g., not kept cold during shipment)
Sample improperly preserved (e.g., not dechlorinated)
• Bottle is broken or lost at the laboratory
• Quality control doesn't meet method specifications when sample is analyzed
You should conduct resampling for the lost sample as soon as possible after the loss is
determined. Only the lost sample needs to be recollected, not the entire sample set that was
collected together. Make sure to note the loss of sample and resample date as a deviation in your
IDSE report.
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C.3 Analytical Method Descriptions
The following are brief summaries of the approved TTHM and HAAS methods.
C.3.1 EPA Method 502.2
Highly volatile compounds with low water solubility, including TTHMs, are extracted
from the water sample by bubbling an inert gas through 5 mL of the sample. The chemical
compounds that are extracted from the water sample are then trapped in a tube that contains
material to which the chemicals attach, or sorb. Once the extraction process has been completed,
the tube containing the extracted chemicals is heated and backflushed with helium, and the
mixture of helium and chemicals enters a capillary gas chromatography (GC) column. The
column is temperature programmed to separate the chemicals extracted from the water, which
are then detected with a photoionization detector (PID) and an electrolytic conductivity detector
(ELCD) placed in series. The amount of each chemical is determined using procedural standard
calibration. The PID is not required if only TTHMs are being measured.
Chemical compounds are identified by comparing the retention times of unknown GC
peaks with retention times for chemical standards analyzed under the same conditions.
Confirmation can be made by comparing the relative response from the two detectors. For
absolute confirmation of results, a gas chromatography/mass spectrometry (GC/MS)
determination can be made using U.S. EPA Method 524.2.
For a complete description of this method see EPA publication: EPA/600/R-95/131
Methods for the Determination of Organic Compounds in Drinking Water: Supplement III.
C.3.2 EPA Method 524.2
Volatile organic compounds, including TTHMs, are extracted from the water sample by
bubbling an inert gas through the sample. Extracted compounds are trapped in a tube that
contains material to which the chemicals attach, or sorb. When the extraction process is
complete, the tube is heated and backflushed with helium to de-sorb the trapped chemicals into a
capillary gas chromatography (GC) column interfaced with a mass spectrometer (MS). The GC
column is temperature programmed to allow for the separation of different chemicals, which are
then detected with the MS. Compounds detected by the MS are identified by comparing their
measured mass spectra and retention times with reference mass spectra and retention times in a
database. Reference mass spectra and retention times for different compounds are obtained by
measuring calibration standards under the same conditions that are used for the water samples.
The concentration of each compound is measured by comparing the MS response of the
compound with the MS response of another compound used as an internal standard. Surrogate
chemicals, whose concentrations are known in every sample, are measured using the same
internal standard calibration procedure.
IDSE Guidance Manual for the Final Stage 2 DBPR C-5 January 2006
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For a complete description of this method see EPA publication: EPA/600/R-95/131
Methods for the Determination of Organic Compounds in Drinking Water: Supplement III.
C.3.3 EPA Method 551.1
A 50 mL volume of the sample is extracted using either 3 mL of methyl-tert-butyl ether
(MTBE) or 5 mL of pentane. A small sub-sample of the extract (2 jiL) is then injected into a GC
equipped with a fused silica capillary column for separation, and a linearized electron capture
detector for analysis. Concentrations of different chemical compounds are determined by
comparing their measured amounts to procedural standard calibration curves.
A typical sample can be extracted and analyzed using this method in 50 minutes for
chlorination byproducts (e.g., TTHM) and chlorinated solvents, and in two hours for all of the
compounds analyzed by this method. Results can be confirmed by using a dissimilar GC column
orbytheuseofGC/MS.
For a complete description of this method see EPA publication: EPA/600/R-95/131
Methods for the Determination of Organic Compounds in Drinking Water: Supplement III.
C.3.4 EPA Method 552.1
A 100 mL volume of the sample is adjusted to pH 5.0 and extracted using a pre-
conditioned miniature anion exchange column. The chemical compounds to be analyzed are first
eluted using small amounts of acidic methanol, and are then esterified directly in this medium
after adding a small volume of methyl-tert-butyl ether (MTBE) as a co-solvent. The methyl
esters are partitioned into the MTBE phase, and are identified and measured using capillary
column gas chromatography with an electron capture detector (GC/ECD).
For a complete description of this method see EPA publication: EPA/600/R-92/129
Methods for the Determination of Organic Compounds in Drinking Water: Supplement II.
C.3.5 EPA Method 552.2
The pH of a 40 mL volume of sample is adjusted to less than 0.5, and the sample is
extracted using 4 mL of methyl-tert-butyl ether (MTBE). The haloacetic acids that have been
partitioned are then converted to their methyl esters by adding acidic methanol and heating them
slightly. The acidic extract is then returned to neutral pH using a saturated solution of sodium
bicarbonate. The chemical compounds of interest are identified and measured using capillary
column gas chromatography with an electron capture detector (GC/ECD). Chemical
concentrations are determined using standard calibration procedures.
IDSE Guidance Manual for the Final Stage 2 DBPR C-6 January 2006
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For a complete description of this method see EPA publication: EPA/600/R-95/131
Methods for the Determination of Organic Compounds in Drinking Water: Supplement III.
C.3.6 EPA Method 552.3
The pH of a 40 mL sample is adjusted to 0.5 or less using concentrated sulfuric acid. The
sample is then extracted with either methyl tert-butyl ether (MTBE) or tert-amyl methyl ether
(TAME) containing an internal standard. The haloacetic acids that have been partitioned are
converted to their methyl esters by adding acidic methanol followed by heating for two hours.
Sodium sulfate is added to separate the partitioned methylated haloacetic acids from the acidic
methanol and the aqueous layer is discarded. The extract is neutralized with a saturated solution
of sodium bicarbonate and the solvent layer is removed for analysis. A gas chromatograph
equipped with a capillary column and an electron capture detector (GC/ECD) is used for
analysis. Chemical concentrations are determined using procedural standard calibration.
For a complete description of this method see Method 552.3 Determination of Haloacetic
Acids andDalapon in Drinking Water by Liquid-LiquidMicroextraction, Derivatization, and
Gas Chromatography with Electron Capture Detection Revision 1.0 (EPA 815-B-03-002),
available from EPA's website at http://www.epa.gov/safewater/methods/sourcalt.html.
C.3.7 Standard Method 6251 B
The sample is extracted using methyl-tert-butyl ether (MTBE) at an acidic pH. A salting
agent is added during the extraction process to increase the extraction's efficiency. Once
extracted, compounds are methylated using diazomethane solution to produce methyl ester or
other ether derivatives that can be separated in a gas chromatograph. A gas chromatograph
equipped with a fused silica capillary column and an electron capture detector (GC/ECD) is used
for analysis. Alternative detectors can be used if quality control criteria are met. Calibration
standards are extracted, methylated, and analyzed in the same manner as the water samples to
compensate for less than 100% recoveries during sample preparation.
For a complete description of this method see Standard Methods for the Examination of
Water and Wastewater: 19th or 20th Edition published jointly by the APHA, AWWA, and WEF
or Standard Methods Online version 6251 B-94 available at http://www.standardmethods.org.
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Appendix D
Consecutive and Wholesale System Issues
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D.I Introduction
If your system is part of a combined distribution system, your compliance schedule for
the IDSE is based on the population served by the largest system in your combined distribution
system. It is important that all systems in a combined distribution system conduct an IDSE at the
same time so that all systems in that combined distribution system know their relative DBF
concentrations and can make the necessary treatment and/or operational changes before Stage 2
compliance begins.
The following questions and answers are provided to help you determine if you are in a
combined distribution system and what this means with respect to your IDSE schedule.
What is a combined distribution system?
The Stage 2 DBPR rule defines combined distribution system, wholesale system, and
consecutive system as follows:
• A 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.
• A wholesale system is a public water system that treats source water as necessary to
produce finished water and then delivers some or all of that finished water to another
public water system. Delivery may be through a direct connection or through the
distribution system of one or more consecutive systems.
• A consecutive system is a public water system that receives some or all of its finished
water from one or more wholesale systems. Delivery may be through a direct
connection or through the distribution system of one or more consecutive systems.
In Example D.I, where system C buys water from system B who buys water from
systems A and D, all four systems are considered to be in the same combined distribution
system. Even if systems A and D never exchange water, they are still considered to be part of
the same combined system.
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Example D.1 Example of a Combined Distribution System
Wholesale System
Treatment
Plant
Wholesale System
Treatment I ^ _, , ' /^ Consecutive System
Plant i
Combined Distribution
System
If you receive water from a wholesale system only on an emergency basis or receive only
a small percentage and small volume of water from a wholesale system, your state may have
excluded you from the combined distribution system. If you deliver water to a consecutive
system only on an emergency basis or deliver only a small percentage and small volume of water
to a consecutive system, your state may also have excluded you from the combined distribution
system. You should receive a letter from EPA or your state that tells you the schedule that was
determined for your system by your state. See Section 2.2 for more information.
How do I know if I am a subpart Hor a ground water system?
If you treat or deliver surface water or ground water under the direct influence of surface
water (GWUDI) as any part of your supply, you are considered a subpart H system. If you treat
or deliver only ground water, you are considered a ground water system. If you treat or deliver a
combination of the two, you are considered a subpart H system. If you do not treat your own
water and you do not know whether you receive surface water, GWUDI, or ground water, you
should consult with your state to determine what your IDSE and Stage 2 compliance monitoring
requirements are.
If I'm in a combined distribution system, which of my IDSE requirements are based on the
population of the largest system in my combined distribution system?
If you are part of a combined distribution system, only your compliance schedule is based
on the population of the largest system in your combined distribution system. Other
requirements are based on your retail population and source water type. The largest system may
be a wholesale system or a consecutive system.
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If I'm in a combined distribution system, which of my IDSE requirements are based on my
individual system's population ?
If you are in a combined distribution system, the number of samples that you must collect
and the frequency at which you must monitor for both the IDSE and Stage 2 DBPR monitoring
are based on your individual system's population.
If I'm in a combined distribution system, when do I submit my 40/30 Certification?
If you are part of combined distribution system and want to submit a 40/30 certification,
submit your request based on the schedule of the largest system in your combined distribution
system using the information in the table below.
Population Served by the Largest System
in the Combined Distribution System
Systems serving > 100,000 people
Systems serving 50,000-99,999 people
Systems serving 10,000-49,999 people
Systems serving < 10,000 people
40/30 Certification Deadline
October 1 , 2006
April 1 , 2007
October 1 , 2007
April 1 , 2008
How does my standard monitoring or system specific study schedule change if I'm in a
combined distribution system?
If you are part of a combined distribution system and plan to conduct standard
monitoring or an SSS, your schedule for conducting activities associated with these IDSE
options is based on the population of the largest system within your combined distribution
system. You can use the table below to help identify the appropriate schedule for your system
for submitting your monitoring plan, performing IDSE monitoring, and submitting your report.
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Population Served by
the Largest System in
the Combined
Distribution System
> 100,000 people
50,000-99,999 people
10,000-49,999 people
< 10,000 people
You Must Submit Your
Standard Monitoring or
SSS Plan to the State
By1
October 1 , 2006
April 1 , 2007
October 1 , 2007
April 1 , 2008
You Should Complete
Any Monitoring By
September 30, 2008
March 31 , 2009
September 30, 2009
March 31, 2010
You Must Complete
Your IDSE Report
By2
January 1, 2009
July 1,2009
January 1, 2010
July 1,2010
1 If the state does not approve or modify your plan within 12 months after the date identified in this column, you may
consider the plan that you submitted as approved and must implement that plan so that you complete standard
monitoring no later than the date identified in the third column.
2 If the state does not approve or modify your report within three months after the date identified in this column (six
months after the date identified in this column if you must comply on the schedule of systems serving 10,000 to
49,999), you may consider the report that you submitted as approved and must implement the recommended Stage 2
compliance monitoring.
What else should I do if I'm in a combined distribution system?
It is very important that you start communicating with the other systems within your
combined distribution system to share data and information. You should copy other systems
within your combined distribution system on correspondence you submit to the EPA or your
state as part of the IDSE process. If you are unsure of what other systems are within your
combined distribution system and how to contact these systems, your state drinking water
program may be able to provide contact information.
Can my combined distribution system be considered one system for the purposes of the IDSE?
No, each individual system must conduct its own IDSE. The schedule for your IDSE
must be based on the population of the largest system in the combined distribution system. The
rest of your IDSE requirements are based on your individual system's population. You cannot
conduct one IDSE for the entire combined distribution system.
Can my combined distribution system be considered one system for the purposes of Stage 2
compliance monitoring?
If your state chooses to use its authority to treat your combined distribution system as one
system for Stage 2 DBPR compliance monitoring, the minimum number of Stage 2 DBPR
monitoring sites and monitoring frequency for the combined distribution system will be based on
the total population and nature of the interconnection of the combined distribution system. Each
consecutive or wholesale system must have at least one Stage 2 compliance monitoring location.
Remember this will only happen if the state allows this option. Consequently, you should
develop your IDSE report for the total number of required Stage 2 compliance locations for your
system unless you hear otherwise from your state.
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D.2 Communication Between Wholesale and Consecutive Systems
As discussed in Section D.I, the Stage 2 DBPR requires consecutive and wholesale
systems to conduct an IDSE at the same time as the largest system in the combined distribution
system. Note that in some cases, this may not be the wholesale provider. This section discusses
recommended approaches for communication between consecutive and wholesale systems when
completing an IDSE.
Consecutive systems are encouraged to contact their wholesale provider as soon as is
reasonably possible after promulgation of the Stage 2 DBPR to determine what plans, if any, the
wholesale system has already made regarding the IDSE. Keep in mind that, while it is
recommended, it is not the responsibility of the wholesale system to contact the consecutive
system regarding the IDSE. Consecutive systems are encouraged to reach out to the wholesale
systems to make the initial contact regarding the IDSE. When a consecutive system receives
water from another consecutive system, communication should involve all three parties, i.e., both
consecutive systems and the wholesale system. At a minimum, you should discuss the following
questions during this initial contact:
1. When are our (both the wholesale and consecutive system) IDSE plans due?
2. When are our IDSE reports due?
3. What type of IDSE does the wholesale system intend to complete (Standard
Monitoring Program or System Specific Study)? Note: Systems are not required to
choose the same IDSE option
4. At what stage in IDSE planning is the wholesale system?
5. During what month(s) does the wholesale system intend to conduct DBF monitoring?
6. Does the wholesale system have water quality data (e.g., temperature, DBF data,
source water quality data, operational data, which wholesale sources serve which
consecutive systems and when) that might help the consecutive system prepare their
IDSE plan?
7. Would the wholesale system be willing to exchange copies of draft IDSE plans with
the consecutive system?
Consecutive systems can consider but are not required to select the same peak historical
month as the wholesale system. The peak historical month for a consecutive system that has
another source(s) may actually be in a different month than the month selected by the wholesale
system. If a consecutive system that has no other sources and that has limited data from which to
make a decision, they could reasonably assume that its peak historical month is the same as the
month selected by the wholesale system.
Consecutive systems that may have limited data can take advantage of water quality data
that may be more readily available to wholesale systems, such as water temperature, source
water quality, disinfectant residual, TTHM, and HAAS data. This will provide them some of the
data needed to work through the recommended steps presented in Chapter 7 for selecting
standard monitoring sites, thus improving the IDSE plan they are able to develop and leading to
better selection of Stage 2 compliance monitoring sites.
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Consecutive systems should attempt to coordinate their IDSE monitoring with that of the
wholesale system. Coordinating IDSE monitoring schedules will allow the two (or more)
systems to better utilize data from the IDSE monitoring period to formulate a Stage 2 DBPR
compliance strategy, if necessary. Additionally, there may be some benefit in trying to better
understand how DBF formation occurs throughout the combined distribution system, especially
if DBF levels are relatively high.
Where it is not possible to coordinate IDSE monitoring, consecutive systems are still
encouraged to work with their wholesale system to coordinate their proposed Stage 2 DBPR
compliance monitoring schedules that must be included in the final IDSE report. Draft and final
copies of the IDSE plans for the consecutive system and the wholesale system should be shared
between the systems. Where a consecutive system receives water through another consecutive
system, all three (or more) systems should share their IDSE plans. This information can be used
to verify that water quality and water age throughout the combined distribution system is
represented through the monitoring plans. For example, if you have multiple entry points from
the same wholesaler, they may have a storage tank prior to one entry point to your system but no
storage tank prior to another entry point. In this case, you would want to select the site after the
tank that is more likely to have high water age as a monitoring location for your standard
monitoring plan.
As IDSE monitoring progresses, consecutive and wholesale systems are encouraged to
share monitoring results. When such an approach is utilized, results can be compared for
consistency and to help identify potential compliance issues related to the Stage 2 DBPR.
A copy of each system's IDSE report should be shared with the other system(s). It is not
necessary for multiple consecutive systems within a combined distribution system to share their
reports, unless one of those systems provides water to another consecutive system, but it is
recommended that the wholesaler provide a copy of its report to each consecutive system, and
each consecutive system provide a copy of its report to the wholesale system. This will help
consecutive systems to determine which compliance strategies, if necessary, are feasible for
them. It will also help the wholesale system to understand DBF formation in the finished water.
Upon completion of the IDSE, it is recommended that consecutive and wholesale systems
work together to discuss their Stage 2 DBPR compliance monitoring schedules for the IDSE
report. As with IDSE monitoring, there may be some benefit in coordinating Stage 2
monitoring. Consecutive systems may want to contract with their wholesale system, or contract
together with the same laboratory to coordinate Stage 2 compliance monitoring. If consecutive
and wholesale systems have the same peak historical month, they may wish to take their samples
at approximately the same time during the peak month. Observing DBF formation throughout
the combined distribution system using Stage 2 compliance monitoring data can help to identify
possible solutions to compliance-related issues.
More information on communication between consecutive and wholesale systems can be
found in EPA's Stage 2 DBPR Consecutive Systems Guidance Manual.
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D.3 Understanding DBF Formation in Combined Distribution Systems
The IDSE will help consecutive and wholesale systems to better understand DBF
formation in their systems. Since the Stage 1 DBPR did not explicitly address consecutive
systems, the IDSE may provide the first opportunity for some consecutive systems to acquire
comprehensive information about DBF levels in their distribution system. As discussed above,
consecutive and wholesale systems should consider coordinating their IDSE sampling schedules
to facilitate a better understanding of DBF formation across the combined distribution system.
Wholesale and consecutive systems should also consider exchanging any existing monitoring
data, particularly any DBF data collected by the wholesale system in the consecutive system.
This data may be helpful to both systems in understanding DBF formation in the combined
distribution system and may help the consecutive system in choosing monitoring locations for
the IDSE.
DBF formation typically increases with water age. Wholesale and consecutive systems
can make a relative estimate of water age by looking at the extent of their wholesale and
consecutive distribution systems, and the distribution of customers. DBF sampling at the entry
point as part of the IDSE can help consecutive systems understand whether DBF formation is
occurring primarily in the wholesale system or the consecutive system. This can help systems to
focus control strategies on the wholesale system, the consecutive system, or a combination of the
two. Information on reducing DBF levels in consecutive systems and discussing compliance
strategies with wholesale systems can be found in EPA's Stage 2 DBPR Consecutive Systems
Guidance Manual.
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Appendix E
Example IDSE Existing Monitoring Results System Specific Study
Plan and Report for a Surface Water System Serving 40,000 People
This appendix is provided as an example IDSE study plan and report for a Subpart H
system serving 40,000 people and opting to complete a System Specific Study (SSS) using
existing monitoring results. The system in this example has a surface water intake with a
treatment plant and two additional wells that are each disinfected at the well locations. In all,
the system has three treatment plants. Because the water blends in the distribution system, the
entire system is categorized as a Subpart H system.
Since the system has three treatment plants, it is required to collect four samples per
treatment plant each quarter for Stage 1 DBPR compliance. The system therefore satisfies the
minimum number of sampling locations required for an Existing Monitoring Results SSS. If the
system submits two years of its Stage 1 DBPR compliance data, it also satisfies the requirement
for minimum number of TTHM and HAAS samples. The Stage 1 DBPR sampling locations are
representative of the distribution system, so the system is not proposing to do any additional
monitoring and is submitting both their IDSE Plan and their IDSE Report by their plan deadline.
Chapter 5 presents detailed guidance on the requirements for performing an existing
monitoring results SSS; selection of Stage 2 compliance monitoring locations; and preparing the
existing monitoring results IDSE report. The application of the basic guidance on the use of
existing monitoring results to select locations meeting the standard monitoring location criteria
and the use of the data to select Stage 2 compliance monitoring locations is shown in this
example.
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Form 2: Existing Monitoring Results SSS Plan page 1 one
I. GENERAL INFORMATION
A. PWS Information* B. Date Submitted*
PWSID: USOOOOOOO Sept. 1, 2007
PWS Name:
PWS Address:
City:
Population Served:
System Type:
HCWS
D NTNCWS
C. PWS Operations
Residual Disinfectant
Number of Disinfectec
D. Contact Person*
Name:
Title:
Phone #:
E-mail:
City of Magnolia
PO Box 1234
Magnolia City State: US Zip: 11111
40,000
Source Water Type: Buying / Selling Relationships:
H Subpart H n Consecutive System
n Ground n Wholesale System
H Neither
Type: is Chlorine n Chloramines n Other
Sources: 1 Surface GWUDI 2 Ground Purchased
Ms. Mary Flower, P.E.
City Engineer
234-555- 1111 Fax #: 234-555-2222
MFIower@ci. magnolia. us
II. SSS REQUIREMENTS*
A. Minimum Number of Monitoring Locations 12
B. Minimum Number of Required Samples
72 TTHM 72 HAAS
C. IDSE Schedule
n Schedule 1 n
Schedule 2 H Schedule 3 n Schedule 4
IDSE Guidance Manual for the Final Stage 2 DBPR E-l
January 2006
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Form 2: Existing Monitoring Results SSS Plan Page20fi6
I. PEAK HISTORICAL MONTH
A. Peak Historical Month* July
B. If Multiple Sources, Source Used to Determine Peak Historical Month
(write "N/A" if only one source in your system)
Surface water source
C. Peak Historical Month Based On (check as many as needed)
H High TTHM D High HAAS H Warmest water temperature
If you used other information to select your peak historical month, explain here
(attach additional sheets if needed):
IV. PREVIOUSLY COLLECTED MONITORING RESULTS*
A. Where were your TTHM and HAAS samples analyzed?
n In-House
Is your in-house laboratory certified? n Yes n No
H Certified Laboratory
Name of certified laboratory: ACME Analytical Services
B. What method(s) was used to analyze your TTHM and HAAS samples?
TTHM HAAS
D EPA 502.2 H EPA 552.1
D EPA 524.2 D EPA 552.2
H EPA 551.1 D EPA 552.3
D SM 6251 B
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Form 2: Existing Monitoring Results SSS Plan pagesof ie
IV. PREVIOUSLY COLLECTED MONITORING RESULTS (Continued)*
(
:. TTHM Results
Site ID1
#1 - Stage 1 SW
Plant Average
Residence Time
#1 - Stage 1 SW
Plant Average
Residence Time
#1 - Stage 1 SW
Plant Average
Residence Time
#2 -Stage 1 SW
Average
Residence Time
#2 - Stage 1 SW
Average
Residence Time
#2 - Stage 1 SW
Average
Residence Time
12-
month
period
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Data
Qualifies
(yes/no)
Yes
Yes
Yes
Yes
Yes
Yes
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
TTHM (mg/L)
1/13/05
0.028
1/11/06
0.024
1/10/07
0.029
1/13/05
0.049
1/11/06
0.045
1/10/07
0.046
4/13/05
0.034
4/12/06
0.033
4/11/07
0.034
4/13/05
0.056
4/12/06
0.052
4/11/07
0.055
7/13/05
0.035
7/12/06
0.037
7/11/07
0.036
7/13/05
0.063
7/12/06
0.060
7/11/07
0.063
10/12/05
0.030
10/11/06
0.031
10/12/05
0.057
10/11/06
0.054
LRAA
0.032
0.031
0.033
0.056
0.053
0.055
1 Verify that site IDs match the site IDs on your distribution system schematic.
Attach additional sheets as needed for previously collected compliance operational and monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
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January 2006
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Form 2: Existing Monitoring Results SSS Plan page4of ie
IV. PREVIOUSLY COLLECTED MONITORING RESULTS (Continued)*
(
:. TTHM Results
Site ID1
#3 - Stage 1 SW
Average
Residence Time
#3 - Stage 1 SW
Average
Residence Time
#3 - Stage 1 SW
Average
Residence Time
#4 -Stage 1 SW
Maximum
Residence Time
#4 - Stage 1 SW
Maximum
Residence Time
#4 - Stage 1 SW
Maximum
Residence Time
12-
month
period
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Data
Qualifies
(yes/no)
Yes
Yes
Yes
Yes
Yes
Yes
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
TTHM (mg/L)
1/13/05
0.038
1/11/06
0.040
1/10/07
0.036
1/13/05
0.032
1/11/06
0.042
1/10/07
0.044
4/13/05
0.047
4/12/06
0.046
4/11/07
0.042
4/13/05
0.060
4/12/06
0.069
4/11/07
0.059
7/13/05
0.065
7/12/06
0.068
7/11/07
0.070
7/13/05
0.074
7/12/06
0.082
7/11/07
0.081
10/12/05
0.052
10/11/06
0.037
10/12/05
0.062
10/11/06
0.071
LRAA
0.050
0.048
0.049
0.057
0.066
0.061
1 Verify that site IDs match the site IDs on your distribution system schematic.
Attach additional sheets as needed for previously collected compliance operational and monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
E-4
January 2006
-------
Form 2: Existing Monitoring Results SSS Plan pagesofie
IV. PREVIOUSLY COLLECTED MONITORING RESULTS (Continued)*
(
:. TTHM Results
Site ID1
#5 - Stage 1
Well 1 Average
Residence Time
#5 - Stage 1
Well 1 Average
Residence Time
#5 - Stage 1
Well 1 Average
Residence Time
#6 - Stage 1
Well 1 Average
Residence Time
#6 - Stage 1
Well 1 Average
Residence Time
#6 - Stage 1
Well 1 Average
Residence Time
12-
month
period
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Data
Qualifies
(yes/no)
Yes
Yes
Yes
Yes
Yes
Yes
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
TTHM (mg/L)
1/13/05
0.038
1/11/06
0.026
1/10/07
0.011
1/13/05
0.032
1/11/06
0.024
1/10/07
0.030
4/13/05
0.025
4/12/06
0.031
4/11/07
0.027
4/13/05
0.051
4/12/06
0.046
4/11/07
0.041
7/13/05
0.030
7/12/06
0.030
7/11/07
0.032
7/13/05
0.058
7/12/06
0.050
7/11/07
0.051
10/12/05
0.032
10/11/06
0.024
10/12/05
0.042
10/11/06
0.049
LRAA
0.031
0.028
0.023
0.046
0.042
0.041
1 Verify that site IDs match the site IDs on your distribution system schematic.
Attach additional sheets as needed for previously collected compliance operational and monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
E-5
January 2006
-------
Form 2: Existing Monitoring Results SSS Plan pageeof ie
IV. PREVIOUSLY COLLECTED MONITORING RESULTS (Continued)*
(
:. TTHM Results
Site ID1
#7 -Stage 1 Well
1 Average
Residence Time
#7 - Stage 1
Well 1 Average
Residence Time
#7 Stage 1 Well
1 Average
Residence Time
#8 - Stage 1
Well 1 Maximum
Residence Time
#8 - Stage 1
Well 1 Maximum
Residence Time
#8 - Stage 1
Well 1 Maximum
Residence Time
12-
month
period
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Data
Qualifies
(yes/no)
Yes
Yes
Yes
Yes
Yes
Yes
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
TTHM (mg/L)
1/13/05
0.031
1/11/06
0.019
1/10/07
0.022
1/13/05
0.038
1/11/06
0.049
1/10/07
0.036
4/13/05
0.037
4/12/06
0.028
4/11/07
0.035
4/13/05
0.051
4/12/06
0.064
4/11/07
0.060
7/13/05
0.045
7/12/06
0.038
7/11/07
0.046
7/13/05
0.075
7/12/06
0.075
7/11/07
0.080
10/12/05
0.033
10/11/06
0.051
10/12/05
0.073
10/11/06
0.072
LRAA
0.037
0.034
0.034
0.059
0.065
0.059
1 Verify that site IDs match the site IDs on your distribution system schematic.
Attach additional sheets as needed for previously collected compliance operational and monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
E-6
January 2006
-------
Form 2: Existing Monitoring Results SSS Plan page? of ie
IV. PREVIOUSLY COLLECTED MONITORING RESULTS (Continued)*
(
:. TTHM Results
Site ID1
#9 - Stage 1
Well 2 Average
Residence Time
#9 - Stage 1
Well 2 Average
Residence Time
#9 - Stage 1
Well 2 Average
Residence Time
#1 0- Stage 1
Well 2 Average
Residence Time
#10 -Stage 1
Well 2 Average
Residence Time
#1 0- Stage 1
Well 2 Average
Residence Time
12-
month
period
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Data
Qualifies
(yes/no)
Yes
Yes
Yes
Yes
Yes
Yes
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
TTHM (mg/L)
1/14/05
0.022
1/12/06
0.024
1/11/07
0.010
1/14/05
0.024
1/12/06
0.016
1/11/07
0.011
4/14/05
0.029
4/13/06
0.022
4/12/07
0.021
4/14/05
0.035
4/13/06
0.043
4/12/07
0.052
7/14/05
0.026
7/13/06
0.031
7/12/07
0.023
7/14/05
0.045
7/13/06
0.060
7/12/07
0.083
10/13/05
0.033
10/12/06
0.026
10/13/05
0.042
10/12/06
0.051
LRAA
0.028
0.026
0.018
0.037
0.043
0.049
1 Verify that site IDs match the site IDs on your distribution system schematic.
Attach additional sheets as needed for previously collected compliance operational and monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
E-7
January 2006
-------
Form 2: Existing Monitoring Results SSS Plan pagesof ie
IV. PREVIOUSLY COLLECTED MONITORING RESULTS (Continued)*
(
:. TTHM Results
Site ID1
#1 1 - Stage 1
Well 2 Average
Residence Time
#1 1 - Stage 1
Well 2 Average
Residence Time
#1 1 - Stage 1
Well 2 Average
Residence Time
#1 2- Stage 1
Well 2 Maximum
Residence Time
#12 -Stage 1
Well 2 Maximum
Residence Time
#1 2- Stage 1
Well 2 Maximum
Residence Time
12-
month
period
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Data
Qualifies
(yes/no)
Yes
Yes
Yes
Yes
Yes
Yes
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
TTHM (mg/L)
1/14/05
0.027
1/12/06
0.021
1/11/07
0.018
1/14/05
0.068
1/12/06
0.069
1/11/07
0.067
4/14/05
0.032
4/13/06
0.047
4/12/07
0.025
4/14/05
0.073
4/13/06
0.077
4/12/07
0.075
7/14/05
0.068
7/13/06
0.060
7/12/07
0.065
7/14/05
0.085
7/13/06
0.089
7/12/07
0.086
10/13/05
0.059
10/12/06
0.045
10/13/05
0.074
10/12/06
0.078
LRAA
0.047
0.043
0.036
0.075
0.078
0.076
1 Verify that site IDs match the site IDs on your distribution system schematic.
Attach additional sheets as needed for previously collected compliance operational and monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
E-8
January 2006
-------
Form 2: Existing Monitoring Results SSS Plan pagegof ie
IV. PREVIOUSLY COLLECTED MONITORING RESULTS (Continued)*
[
D. HAAS Results
Site ID1
#1 - Stage 1 SW
Plant Average
Residence Time
#1 - Stage 1 SW
Plant Average
Residence Time
#1 - Stage 1 SW
Plant Average
Residence Time
#2 -Stage 1 SW
Average
Residence Time
#2 - Stage 1 SW
Average
Residence Time
#2 - Stage 1 SW
Average
Residence Time
12-
month
period
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Data
Qualifies
(yes/no)
Yes
Yes
Yes
Yes
Yes
Yes
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
HAAS (mg/L)
1/13/05
0.028
1/11/06
0.024
1/10/07
0.029
1/13/05
0.049
1/11/06
0.045
1/10/07
0.046
4/13/05
0.034
4/12/06
0.033
4/11/07
0.034
4/13/05
0.059
4/12/06
0.052
4/11/07
0.055
7/13/05
0.035
7/12/06
0.037
7/11/07
0.036
7/13/05
0.063
7/12/06
0.060
7/11/07
0.063
10/12/05
0.030
10/11/06
0.031
10/12/05
0.057
10/11/06
0.054
LRAA
0.032
0.031
0.033
0.057
0.053
0.055
1 Verify that site IDs match the site IDs on your distribution system schematic.
Attach additional sheets as needed for previously collected compliance operational and monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
E-9
January 2006
-------
Form 2: Existing Monitoring Results SSS Plan page 10 one
IV. PREVIOUSLY COLLECTED MONITORING RESULTS (Continued)*
[
D. HAAS Results
Site ID1
#3 -Stage 1 SW
Average
Residence Time
#3 - Stage 1 SW
Average
Residence Time
#3 -Stage 1 SW
Average
Residence Time
#4 -Stage 1 SW
Maximum
Residence Time
#4 - Stage 1 SW
Maximum
Residence Time
#4 - Stage 1 SW
Maximum
Residence Time
12-
month
period
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Data
Qualifies
(yes/no)
Yes
Yes
Yes
Yes
Yes
Yes
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
HAAS (mg/L)
1/13/05
0.022
1/11/06
0.024
1/10/07
0.017
1/13/05
0.039
1/11/06
0.023
1/10/07
0.027
4/13/05
0.035
4/12/06
0.041
4/11/07
0.045
4/13/05
0.049
4/12/06
0.044
4/11/07
0.051
7/13/05
0.052
7/12/06
0.059
7/11/07
0.065
7/13/05
0.058
7/12/06
0.052
7/11/07
0.060
10/12/05
0.031
10/11/06
0.037
10/12/05
0.041
10/11/06
0.039
LRAA
0.035
0.040
0.042
0.047
0.040
0.046
1 Verify that site IDs match the site IDs on your distribution system schematic.
Attach additional sheets as needed for previously collected compliance operational and monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
E-10
January 2006
-------
Form 2: Existing Monitoring Results SSS Plan pagen one
IV. PREVIOUSLY COLLECTED MONITORING RESULTS (Continued)*
[
D. HAAS Results
Site ID1
#5 - Stage 1
Well 1 Average
Residence Time
#5 - Stage 1
Well 1 Average
Residence Time
#5 - Stage 1
Well 1 Average
Residence Time
#6 - Stage 1
Well 1 Average
Residence Time
#6 - Stage 1
Well 1 Average
Residence Time
#6 - Stage 1
Well 1 Average
Residence Time
12-
month
period
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Data
Qualifies
(yes/no)
Yes
Yes
Yes
Yes
Yes
Yes
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
HAAS (mg/L)
1/13/05
0.029
1/11/06
0.026
1/10/07
0.025
1/13/05
0.040
1/11/06
0.037
1/10/07
0.042
4/13/05
0.036
4/12/06
0.034
4/11/07
0.035
4/13/05
0.045
4/12/06
0.043
4/11/07
0.048
7/13/05
0.043
7/12/06
0.046
7/11/07
0.049
7/13/05
0.051
7/12/06
0.050
7/11/07
0.053
10/12/05
0.033
10/11/06
0.037
10/12/05
0.044
10/11/06
0.044
LRAA
0.035
0.036
0.036
0.045
0.044
0.048
1 Verify that site IDs match the site IDs on your distribution system schematic.
Attach additional sheets as needed for previously collected compliance operational and monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
E-ll
January 2006
-------
Form 2: Existing Monitoring Results SSS Plan page 12 one
IV. PREVIOUSLY COLLECTED MONITORING RESULTS (Continued)*
[
D. HAAS Results
Site ID1
#7 -Stage 1 Well
1 Average
Residence Time
#7 - Stage 1
Well 1 Average
Residence Time
#7 Stage 1 Well
1 Average
Residence Time
#8 - Stage 1
Well 1 Maximum
Residence Time
#8 - Stage 1
Well 1 Maximum
Residence Time
#8 - Stage 1
Well 1 Maximum
Residence Time
12-
month
period
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Data
Qualifies
(yes/no)
Yes
Yes
Yes
Yes
Yes
Yes
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
HAAS (mg/L)
1/13/05
0.049
1/11/06
0.045
1/10/07
0.048
1/13/05
0.030
1/11/06
0.026
1/10/07
0.028
4/13/05
0.055
4/12/06
0.052
4/11/07
0.057
4/13/05
0.057
4/12/06
0.042
4/11/07
0.045
7/13/05
0.064
7/12/06
0.061
7/11/07
0.065
7/13/05
0.066
7/12/06
0.053
7/11/07
0.064
10/12/05
0.056
10/11/06
0.054
10/12/05
0.053
10/11/06
0.054
LRAA
0.056
0.053
0.057
0.052
0.044
0.046
1 Verify that site IDs match the site IDs on your distribution system schematic.
Attach additional sheets as needed for previously collected compliance operational and monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
E-12
January 2006
-------
Form 2: Existing Monitoring Results SSS Plan page 13 one
IV. PREVIOUSLY COLLECTED MONITORING RESULTS (Continued)*
[
D. HAAS Results
Site ID1
#9 - Stage 1
Well 2 Average
Residence Time
#9 - Stage 1
Well 2 Average
Residence Time
#9 - Stage 1
Well 2 Average
Residence Time
#1 0- Stage 1
Well 2 Average
Residence Time
#10 -Stage 1
Well 2 Average
Residence Time
#1 0- Stage 1
Well 2 Average
Residence Time
12-
month
period
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Data
Qualifies
(yes/no)
Yes
Yes
Yes
Yes
Yes
Yes
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
HAAS (mg/L)
1/14/05
0.032
1/12/06
0.030
1/11/07
0.031
1/14/05
0.031
1/12/06
0.037
1/11/07
0.038
4/14/05
0.038
4/13/06
0.041
4/12/07
0.036
4/14/05
0.037
4/13/06
0.044
4/12/07
0.043
7/14/05
0.046
7/13/06
0.048
7/12/07
0.045
7/14/05
0.056
7/13/06
0.053
7/12/07
0.051
10/13/05
0.035
10/12/06
0.039
10/13/05
0.044
10/12/06
0.042
LRAA
0.038
0.040
0.037
0.042
0.044
0.044
1 Verify that site IDs match the site IDs on your distribution system schematic.
Attach additional sheets as needed for previously collected compliance and operational monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
E-13
January 2006
-------
Form 2: Existing Monitoring Results SSS Plan page u one
IV. PREVIOUSLY COLLECTED MONITORING RESULTS (Continued)*
[
D. HAAS Results
Site ID1
#1 1 - Stage 1
Well 2 Average
Residence Time
#1 1 - Stage 1
Well 2 Average
Residence Time
#1 1 - Stage 1
Well 2 Average
Residence Time
#1 2- Stage 1
Well 2 Maximum
Residence Time
#12 -Stage 1
Well 2 Maximum
Residence Time
#1 2- Stage 1
Well 2 Maximum
Residence Time
12-
month
period
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Jan 05-
Jan 06
Jan 06-
Jan 07
Jan 07-
July07
Data
Qualifies
(yes/no)
Yes
Yes
Yes
Yes
Yes
Yes
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
HAAS (mg/L)
1/14/05
0.038
1/12/06
0.042
1/11/07
0.037
1/14/05
0.040
1/12/06
0.043
1/11/07
0.040
4/14/05
0.043
4/13/06
0.046
4/12/07
0.042
4/14/05
0.045
4/13/06
0.047
4/12/07
0.048
7/14/05
0.050
7/13/06
0.053
7/12/07
0.051
7/14/05
0.048
7/13/06
0.052
7/12/07
0.056
10/13/05
0.044
10/12/06
0.045
10/13/05
0.043
10/12/06
0.046
LRAA
0.044
0.047
0.043
0.044
0.047
0.048
1 Verify that site IDs match the site IDs on your distribution system schematic.
Attach additional sheets as needed for previously collected compliance and operational monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
E-14
January 2006
-------
Form 2: Existing Monitoring Results SSS Plan page
15 of 16
V. CERTIFICATION OF DATA*
I hereby certify that:
The reported monitoring results include all compliance and non-compliance
results generated during the time period beginning with the first reported result
and ending with the most recent Stage 1 DBPR results.
The samples are representative of the entire distribution system.
Treatment and the distribution system have not changed significantly since the
samples were collected.
Signature:
Date: May 30, 2007
VI. PROPOSED SSS MONITORING SCHEDULE*
Skip if you are submitting your IDSE Report at the same time as your plan
SSS Site ID
(from map)1
Projected Sampling Date (date or week)2
period 1
period 2
period 3
period 4
period 5
period 6
1 Verify that site IDs match IDs on your distribution system schematic (See Section VII of this
form). Attach additional copies of this sheet if necessary.
2 period = monitoring period. Can list exact date or week (e.g., week of 7/9/07)
IDSE Guidance Manual for the Final Stage 2 DBPR E-15
January 2006
-------
Form 2: Existing Monitoring Results SSS Plan pagei6 one
VII. DISTRIBUTION SYSTEM SCHEMATIC*
ATTACH a schematic of your distribution system.
Distribution system schematics are not confidential and should not contain information that
poses a security risk to your system. EPA recommends that you use one of two options:
Option 1: Distribution system schematic with no landmarks or
addresses indicated. Show locations of sources, entry points, storage
facilities, operational monitoring locations, and Stage 1 compliance
monitoring locations (required). Also include pressure zone boundaries
and locations of pump stations. Provide map scale.
Option 2: City map without locations of pipes indicated. Show
locations of sources, entry points, storage facilities, operational monitoring
locations, and Stage 1 compliance monitoring locations (required). Also
include boundaries of the distribution system, pressure zone boundaries
and locations of pump stations. Provide map scale.
VIM. ATTACHMENTS
D Additional sheets for explaining how you selected the peak historical month
(Section III).
D Additional sheets for previously collected monitoring results (Section IV).
D Additional sheets for proposed monitoring dates (Section VI).
H Distribution system schematic* (Section VII).
Total Number of Pages in Your Plan: 17
Note: Fields with an asterisk (*) are required by the Stage 2 DBPR.
IDSE Guidance Manual for the Final Stage 2 DBPR E-16 January 2006
-------
Magnolia City Distribution System Schematic
Attachment #9
Friendship Heights Well
Field and Pumping
Station
Elected Storage Tank
Ground StorageTank
Pump Station
Well Field and
Pumping Station
O Stage 1 DBPR site
Columbus Well
Field and Pumping
Station
IDSE Guidance Manual for the Final Stage 2 DBPR E-l 7
January 2006
-------
This page intentionally left blank.
IDSE Guidance Manual for the Final Stage 2 DBPR E-18 January 2006
-------
Form 3: IDSE Report for an Existing Monitoring
ReSUltS SSS Page 1 of 5
I. GENERAL INFORMATION
(Skip this section if you are submitting the plan and report at the same time)
A. PWS Information*
PWSID:
PWS Name:
PWS Address:
City:
Population Served:
B. Date Submitted*
State:
Zip:
System Type:
news
D NTNCWS
Source Water Type:
D Subpart H
n Ground
Buying / Selling Relationships:
D Consecutive System
D Wholesale System
D Neither
C. PWS Operations
Residual Disinfectant Type: n Chlorine n Chloramines n Other_
Number of Disinfected Sources:
Surface
GWUDI
Ground
Purchased
D. Contact Person*
Name:
Title:
Phone #:
E-mail:
Fax#:
II. STAGE 2 DBPR REQUIREMENTS*
A. Number of required Stage 2 DBPR Compliance Monitoring Sites 4 TOTAL
2 Highest TTHM 1 Stage 1 DBPR 1 Highest HAAS
IDSE Guidance Manual for the Final Stage 2 DBPR E-19
January 2006
-------
Form 3: IDSE Report for an Existing Monitoring
ReSUltS SSS Page2of5
II. STAGE 2 DBPR REQUIREMENTS (continued)*
B. IDSE Schedule C. Required Stage 2 DBPR Compliance Monitoring
Frequency
D Schedule 1 n During peak historical month (1 monitoring period)
D Schedule 2 is Every 90 days (4 monitoring periods)
H Schedule 3
D Schedule 4
III. ADDITIONAL SSS AND STAGE 1 COMPLIANCE MONITORING RESULTS*
(Skip this section if you are submitting the plan and report at the same time)
A. Where were your TTHM and HAAS samples analyzed?
n In-House
Is your in-house laboratory certified? n Yes n No
n Certified Laboratory
Name of certified laboratory:
B. What method(s) was used to analyze your TTHM and HAAS samples?
TTHM HAAS
D EPA 502.2 D EPA 552.1
D EPA 524.2 D EPA 552.2
D EPA 551.1 D EPA 552.3
D SM 6251 B
IDSE Guidance Manual for the Final Stage 2 DBPR E-20 January 2006
-------
Form 3: IDSE Report for an Existing Monitoring
ReSUltS SSS Page 3 of 5
IV. JUSTIFICATION OF STAGE 2 DBPR COMPLIANCE MONITORING SITES*
Stage 2
Compliance
Monitoring
Site ID
#1 2- Stage 1
Well 2 Max
Residence
Time
#2 - Stage 1
SW Plant Ave
Residence
Time Site
#7 - Stage 1
Well 1 Av
Residence
Time
# 4 - Stage 1
SW plant max
residence time
Site Type
EI Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
EI Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
El Stage 1 DBPR
El Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
Justification
1st highest TTHM LRAA.
Sampled quarterly at all sites, so compared LRAAs for
all sites instead of comparing individual sample results
from peak historical month. This is true for the selection
of all Stage 2 compliance monitoring sites.
1st highest HAAS; site #7 had the same LRAA result.
Site #7 is selected for the Stage 1 site.
Stage 1 site with highest HAAS LRAA
2nd highest TTHM LRAA
Attach additional copies of this sheet if you need more room.
IDSE Guidance Manual for the Final Stage 2 DBPR E-21
January 2006
-------
Form 3: IDSE Report for an Existing Monitoring
ReSUltS SSS Page4of5
V. PEAK HISTORICAL MONTH
A.
B.
Peak Historical Month* July
Is Your Peak Historical Month the Same as In Your SSS Plan?
H Yes D No
If no, explain how you selected your new peak historical month (attach
additional sheets if needed):
VI. PROPOSED STAGE 2 DBPR COMPLIANCE MONITORING SCHEDULE*
Stage 2
Compliance
Monitoring
Site ID
#12
#2
#7
#4
Projected Sampling Date (date or week) 1
period 1
7/15/2013
7/15/2013
7/15/2013
7/15/2013
period 2
10/15/2013
10/15/2013
10/15/2013
10/15/2013
period 3 period 4
1/15/2014 4/15/2014
1/15/2014 4/15/2014
1/15/2014 4/15/2014
1/15/2014 4/15/2014
1 period = monitoring period. Complete for the number of monitoring periods from
Section II. C.
Attach additional copies of this sheet if you need more room.
IDSE Guidance Manual for the Final Stage 2 DBPR E-22
January 2006
-------
Form 3: IDSE Report for an Existing Monitoring
SSS Page 5 of 5
VII. DISTRIBUTION SYSTEM SCHEMATIC*
(Skip this section if you are submitting the plan and report at the same time)
ATTACH a schematic of your distribution system if it has changed since you submitted
your Existing Monitoring Results SSS Plan (Form 2).
VIM. ATTACHMENTS
D Additional sheets for Additional SSS Monitoring Results (Section III).
D Additional sheets for Stage 2 DBPR Monitoring Sites (Section IV). REQUIRED if you
are a subpart H system serving more than 249,999 people.
D Additional sheets for explaining how you selected the peak historical month (Section
V).
D Additional sheets for proposed compliance monitoring dates (Section VI). REQUIRED if
you are a subpart H system serving more than 249,999 people.
D Explanation of deviations from approved study plan.
D Distribution system schematic* (Section VII). REQUIRED if it has changed from your
approved SSS plan.
D Compliance calculation procedures (for Stage 2 Compliance Monitoring Plan).
Total Number of Pages in Your Report: 5
Note: Fields with an asterisk (*) are required by the Stage 2 DBPR.
IDSE Guidance Manual for the Final Stage 2 DBPR E-23 January 2006
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This page intentionally left blank.
IDSE Guidance Manual for the Final Stage 2 DBPR E-24 January 2006
-------
Appendix F
Example IDSE System Specific Study Using a Hydraulic Model for
a Surface Water System Serving 57,000 People
This appendix is provided as an example IDSE plan and report for a surface water
system serving 57,000 people and opting to complete a System Specific Study (SSS) using a
water distribution system model. For this example, the state did not require any modifications to
the study plan and the system did not deviate from the approved study plan.
Chapter 6 presents detailed guidance on the requirements for performing a modeling
SSS, selecting Stage 2 DBPR compliance monitoring locations using modeling SSS data, and
preparing a modeling SSS report. The application of the basic guidance on preliminary location
selection and Stage 2 DBPR compliance monitoring location selection is shown in this example,
along with several instances of the use of best professional judgement being applied.
-------
This page intentionally left blank.
-------
Form 4: Modeling Study Plan pagei ore
I. GENERAL INFORMATION
A. PWS Information*
PWSID: US1111111
B. Date Submitted* 3/8/07
PWS Name: Big City Water System
PWS Address: 1234 Main Street
City: Big City State: US Zip: 99999
Population Served: 57
System Type:
B CWS
D NTNCWS
C. PWS Operations
Residual Disinfectant Ty
Number of Disinfected S
D. Contact Person*
Name: Mr
000
Source Water Type:
H Subpart H
n Ground
pe: H Chlorine n Ch
ources: 1 Surface
. John Smith, P.E.
Buying / Selling Relationships:
n Consecutive System
n Wholesale System
H Neither
loramines n Other:
GWUDI Ground Purchased
Title: Water System Manager
Phone #: 123-555-0000
Fax#: 123-555-0001
E-mail: jsmith@ci.bigcity.us
II. IDSE REQUIREMENTS*
A. SSS Monitoring
B. Schedule C.
Number of Samples
per Monitoring Period: „„ ~ , , , „ (
K 16 D Schedule 1
Number of Monitoring
Periods:
H Schedule 2 [
1 D Schedule 3
Total: 16 D Schedule 4
SSS Monitoring Frequency
a During peak month of TTHM formation
1 monitoring period)
D Additional (describe)
IDSE Guidance Manual for the Final Stage 2 DBPR F-l
January 2006
-------
Form 4: Modeling Study Plan
Page 2 of 6
III. MODEL DESCRIPTION
A. Answer Yes or No to the following questions*
(provide documentation in attached sheets)
1. Is your model an Extended Period Simulation model?
2. Does your model meet the minimum requirements described
below? Attach tables or spreadsheets to demonstrate that your
model meets these requirements.
Include 75% of pipe volume
Include 50% of pipe length
Include all pressure zones
Include all pipes 12" and larger
Include all 8" and larger pipes that connect pressure
zones, influence zones from different sources, storage
facilities, major demand areas, pumps, and control valves,
or are known or expected to be significant conveyors of
water
Include all 6" and larger pipes that connect remote areas
of a distribution system to the main portion of the system
Include all storage facilities with standard operations
represented in the model
Include all active pump stations with realistic controls
Include all active control valves
3. Is your model (or will it be) calibrated to simulate actual water
levels at all storage facilities and represent the current distribution
system configuration during the period of high TTHM formation?
4. If calibration is complete, does the model simulate 24 hour
variation in demand and show a consistently repeating 24 hour
pattern of residence time?
R Provide a history of your model development and calibration*,
dates (attach additional sheets if needed)
See attached sheet.
(Y)/N
(Y)N
(Y)/N
(Y)N
©N
(Y)/N
(Y/N
(Y)/N
Q/N
(Y)/N
(V)/N
(Vy N
w
including
IDSE Guidance Manual for the Final Stage 2 DBPR F-2 January 2006
-------
Form 4: Modeling Study Plan page30f6
III. MODEL DESCRIPTION (Continued)
C.
1.
2.
3.
4.
D.
1.
2.
3.
4.
How was demand data assigned to the model? (attach additional sheets if
needed)
What method was used to assign
demands throughout the system?
How did you estimate diurnal demand
variation? How did you determine
total system demand?
How many demand categories did
you use?
How did you address large water
users?
Customer accounts were geocoded and
assigned to each node using Thiessen
polygons.
Diurnal demand patterns were calculated using a
mass balance into/out of each pressure zone using
the calibration data. Total system demand was
calculated based on water production records from
the WTP.
6 different demand categories were used:
residential (based on calculation described above),
industrial, school, golf course, swimming pool, and
one for a specific industry.
Large water users were asked about their demand
patterns. One industry had a usage pattern that
was much different than the others so it was
assigned an individual pattern.
Describe all calibration activities* If your model is not currently calibrated,
describe how calibration will be completed within 12 months of plan
submission using the questions 1-8 as guidance (attach additional sheets if
needed)
When was the model last calibrated?
What types of data were used in the
calibration?
When was the calibration data
collected?
What field tests have been performed
to collect calibration data?
The model was calibrated in 2003 to conditions in
July 2002.
SCADA readings for tank levels, pump flows, and
pump discharge pressures were collected on 5
minute intervals. 6 pressure recorders with
dataloggers were installed in system for 1 week.
July 12 to July 19, 2002
No field tests were performed.
IDSE Guidance Manual for the Final Stage 2 DBPR F-3
January 2006
-------
Form 4: Modeling Study Plan F,,^^,
III. MODEL DESCRIPTION (Continued)
D.
5.
6.
7.
8.
(Continued)
How did you determine friction factors
(C-factors)?
Was the calibration completed for the
peak month for TTHM formation? If
not, was the model performance
verified for the peak month for TTHM
formation?
How well do actual tank levels
correlate with predicted tank levels
during the peak month for TTHM
formation?
See Attachments (Section VIM) for
additional submission
requirements.
If you are using a water quality model,
what parameters are modeled? How
was the model calibrated?
C-factors were determined through trial and error
simulations to fit the calibration data as closely as
possible. Pipe material and pipe diameter were
also considered when determining C-factors.
The peak month is August. The model calibration
was verified using SCADA data for tank levels in
August 2006.
The August 2006 actual tank levels are predicted
well (within 2 feet) by the model. See attached
graphs.
n/a
IV. PEAK MONTH FOR TTHM FORMATION
A.
B.
Peak Month For TTHM Formation*
Auqust
Justification of Peak Month for TTHM Formation
Describe how your system determined which month is the peak month for TTHM
formation (attach additional sheets if needed):
High temperature and high source water TOC, based on past 5 years of data
IDSE Guidance Manual for the Final Stage 2 DBPR F-4
January 2006
-------
Form 4: Modeling Study Plan
Page 5 of 6
V. MODELING INFORMATION
How was the SSS modeling performed? (attach additional sheets as needed)
1.
2.
3.
4.
Was modeling done for the operating
conditions during the peak month for
TTHM formation?
How were operational controls
represented in the model?
How was water age simulated during
the peak month for TTHM formation
(time steps, length of simulation,
etc.)? If not yet done, indicate how
this will be addressed in the IDSE
report.
What are the average water age
results for your distribution system?
See Attachments (Section VIM) for
additional submission
requirements.
Yes, modeling was done for August 2006 conditions.
Logical controls for all pump stations were set using tank
level set points for summer operation.
The water age simulation was run for 960 hours to
ensure full turnover of all tanks. Tank #2 had the high
average water age.
The average water age (for the final 24 hours of the 960
hour simulation) is given in the attached table. Nodes
with zero demand have a water age approximately equal
to 960 hours and were not considered in the analysis for
site selection.
Table is attached.
VI. PLANNED STAGE 1 DBPR COMPLIANCE MONITORING SCHEDULE*
Stage 1 DBPR
Monitoring Site
ID (from map) 1
Stage 1 #1
Stage 1 #2
Stage 1 #3
Stage 1 #4
Projected Sampling Date (date or week) 2
Period 1
3/12/2008
3/12/2008
3/12/2008
3/12/2008
Period 2
6/7/2008
6/7/2008
6/7/2008
6/7/2008
Period 3
8/22/2008
8/22/2008
8/22/2008
8/22/2008
Period 4
10/1/2008
10/1/2008
10/1/2008
10/1/2008
1 Verify that site IDs match IDs on your distribution system schematic (See Section VII of
this form). Attach additional copies if you are required to monitor at more than 8 Stage 1
DBPR sites.
2 period = monitoring period. Complete for the number of periods in which you must conduct
Stage 1 DBPR monitoring during IDSE monitoring. Can list exact date or week (e.g., week
of 7/9/07)
IDSE Guidance Manual for the Final Stage 2 DBPR F-5
January 2006
-------
Form 4: Modeling Study Plan
Page 6 of 6
VII. DISTRIBUTION SYSTEM SCHEMATIC*
ATTACH a schematic of your distribution system.
Distribution system schematics are not confidential and should not contain information that
poses a security risk to your system. EPA recommends that you submit the following:
Distribution system schematic with no landmarks or addresses indicated. Show
locations of sources, entry points, storage facilities, locations of completed monitoring,
and Stage 1 compliance monitoring locations (required). Also include pressure zone
boundaries and locations of pump stations. Provide map scale.
VIM. ATTACHMENTS
H Distribution System Schematic* (Section VII).
H Tabular or spreadsheet documentation that your model meets minimum
requirements* (Section III.A).
H Additional sheets for explaining your model (Section III.B).
H Graph of predicted tank levels vs. measured tank levels for the storage facility with
the high residence time in each pressure zone* (Section III.D). Required if
calibration is complete.
H Time series graph of water age at the longest residence time storage facility in the
distribution system showing the predictions for the entire EPS simulation period*
(Section V). Required if calibration is complete
D Additional sheets for explaining how you selected the peak historic month for TTHM
formation (Section V).
H Model output showing preliminary 24 hour water age predictions for all nodes
throughout the distribution system* (Required for all submissions. If your model is
calibrated, this should be your final water age predictions)(Section V).
D Additional sheets describing the planned Stage 1 DBPR Compliance Monitoring
Schedule (Section VI).
Total Number of Pages in Your Plan: 19
Note: All items marked with an asterisk (*) are required by the rule.
IDSE Guidance Manual for the Final Stage 2 DBPR F-6 January 2006
-------
Distribution System Schematic
Modeling SSS Plan
^^^™ i • : • .
H ;til t-u 1o n m -'ilti :
n -i.i 3 &•
FaolllV
'**) 'i:*J Sfctlll
O
Scale 1:8,000
IDSE Guidance Manual for the Final Stage 2 DBPR F- 7
January 2006
-------
MINIMUM MODEL REQUIREMENTS
No GIS system for the water mains exists. Using information from the paper water atlas sheets
for the City and the model input data, the following characteristics were estimated. There are no
active control valves in the distribution system.
Pipe
Diameter
(in)
4
6
8
10
12
16
20
24
Total
Length (ft)
Total
15,142
234,996
156,720
15,505
136,404
26,815
12,832
1,761
600,175
Not In
Model
10,400
4,000
0
0
0
0
0
0
14,400
In Model
4,472
230,996
156,720
15,505
136,404
26,815
12,832
1,761
585,775
%in
Model
31.3
98.3
100.0
100.0
100.0
100.0
100.0
100.0
97.6
Volume (cf)
Total
1,321
46,141
54,706
8,457
107,131
37,441
27,995
5,532
288,725
Not In
Model
908
785
0
0
0
0
0
0
1,693
In
Model
414
45,356
54,706
8,457
107,131
37,441
27,995
5,532
287,032
%in
Model
31.3
98.3
100.0
100.0
100.0
100.0
100.0
100.0
99.4
IDSE Guidance Manual for the Final Stage 2 DBPR F-8
January 2006
-------
HISTORY OF MODEL DEVELOPMENT AND CALIBRATION
Model was developed in 2003 and calibrated to conditions in July 2002 (maximum demand day).
No new major facilities have been constructed in the system since 2003. The model was used to
determine new pipe sizes for future construction, to adjust operation of the pumps, to examine
water age, and to identify fire flow improvements. New mains that were constructed since 2003
have been added to the model.
ADDITIONAL MODEL INFORMATION
Pump Station Controls
Pump Station
WTP High
Service
PS#1
PS #2
Controlling
Tank
Tank#1
Tank #3
Tank #4
Pump Number
1 (Lead)
2(Lag1)
3 (Lag 2)
4 (Lag 3)
1 (Lead)
2(Lag1)
3 (Lag 2)
1(Lag1)
2 (Lead)
3 (Lag 2/Fire)
Pump ON
Level (ft)
27.0
26.0
24.0
20.0
25.0
24.0
23.5
28.0
30.0
20.0
Pump OFF
Level (ft)
28.5
28.5
28.0
26.5
29.0
28.0
27.0
33.0
35.0
30.0
Tank Information
Tank
1
2
3
4
Pressure Zone
Central
East
East
West
Average Water Age (hrs)
120.08
134.19
77.33
60.89
IDSE Guidance Manual for the Final Stage 2 DBPR F-9
January 2006
-------
0)
899 i
CALIBRATION RESULTS
Tank #1, Central Pressure Zone
Calibration Verification Results -August2006 Data
• Measured
Modeled
889
8/24/20060:00 8/24/200612:00 8/25/20060:00 8/25/200612:00 8/26/20060:00 8/26/200612:00 8/27/20060:00
Date/Time
IDSE Guidance Manual for the Final Stage 2 DBPR
F-10
January 2006
-------
1032 -i
CALIBRATION RESULTS (CONTINUED)
Tank #2, East Pressure Zone
Calibration Verification Results -August2006 Data
Measured
Modeled
1025 -
1024
8/24/20060:00 8/24/200612:00 8/25/20060:00 8/25/200612:00 8/26/20060:00 8/26/200612:00 8/27/20060:00
Date/Time
IDSE Guidance Manual for the Final Stage 2 DBPR
F-ll
January 2006
-------
CALIBRATION RESULTS (CONTINUED)
1013
1012
Tank #4, West Pressure Zone
Calibration Verification Results -August2006 Data
Measured
Modeled
1006
1005
8/24/20060:00 8/24/200612:00 8/25/20060:00 8/25/200612:00 8/26/20060:00 8/26/200612:00 8/27/20060:00
Date/Time
IDSE Guidance Manual for the Final Stage 2 DBPR
F-12
January 2006
-------
MODELING ANALYSIS RESULTS
Water Age for Tank 2
140
120-
100-
1/r so-!
o
-------
MODELING ANALYSIS RESULTS
Average Water Age for All Nodes (Hour 936 to Hour 960 of Simulation)
ID
10
12
14
16
18
20
22
24
26
28
30
32
34
36
38
40
42
44
46
48
50
52
54
56
58
60
62
64
66
68
70
72
74
76
78
80
82
84
86
88
90
92
94
Average
(hrs)
263.32
3.05
21.28
4.68
581.18
5
947.93
947.81
246.72
16.64
947.76
947.76
32.95
18.67
0.04
0.38
183.79
2.96
0.09
0.16
0.25
0.33
0.16
0.31
0.15
894.92
2.84
886.42
0.15
0.24
0
894.96
934.2
889.41
0.81
0.68
0.63
947.93
579.20
0.4
93.09
14.19
19.75
ID
96
98
100
102
104
106
108
110
112
114
116
118
120
122
124
126
128
130
132
134
136
138
140
142
144
146
148
150
152
154
156
158
160
162
164
166
168
170
172
174
176
178
180
Average
(hrs)
0.76
0.83
0.95
947.88
947.88
333.21
264.09
270.36
33.79
947.93
947.93
419.19
331.35
288.94
65.68
174.07
40.42
0.05
847.23
947.93
290.74
1.12
20.57
1.36
497.02
21.59
0.12
751.59
947.93
947.93
355.98
18.04
0.08
491.68
947.93
947.93
230.29
24.57
549.5
587.53
947.93
947.93
1.45
ID
182
184
186
188
190
192
194
196
198
200
202
204
206
208
210
212
214
216
218
220
222
224
226
228
230
232
234
236
238
240
242
244
246
248
250
252
254
256
258
260
262
264
266
Average (hrs)
1.47
18.37
16.35
9.42
48.29
34.8
58.32
52.38
44.4
46.24
44.64
40.19
46.77
947.93
47.64
48.59
45.22
41.58
49.83
43.94
8.77
947.93
947.93
34.13
39.62
42.32
35.18
36.64
11.73
947.93
11.4
947.93
9.9
46
947.93
17.1
15.64
25.88
947.93
4.89
5.02
947.93
947.93
ID
268
270
272
274
276
278
280
282
284
286
288
292
294
296
298
300
302
304
306
308
310
312
314
316
318
320
322
324
326
328
330
332
334
336
338
340
342
344
346
348
350
352
354
Average (hrs)
6.57
13.57
79.19
172.01
280.49
35.64
947.93
27.33
947.93
27.3
947.93
26.54
947.93
25.95
54.63
76.66
23.47
28.74
22.85
8.04
21.75
27.97
23.31
22.94
4.14
6.65
4.5
947.93
3.71
1.98
3.43
3.19
947.93
947.93
2.9
2.5
3.12
947.93
3.64
34.98
947.93
99.19
947.93
IDSE Guidance Manual for the Final Stage 2 DBPR F-14
January 2006
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MODELING ANALYSIS RESULTS (CONTINUED)
Average Water Age for All Nodes (Hour 936 to Hour 960 of Simulation)
ID
356
358
360
362
364
366
368
370
372
374
376
378
380
384
388
390
392
394
396
398
400
402
404
406
408
410
412
414
416
418
420
422
424
426
428
430
432
434
436
438
440
442
444
Average
(hrs)
17.38
947.93
947.93
947.93
83.58
947.93
947.93
7.49
12.99
29.83
6.76
919.41
223.06
20.56
12.38
13.03
1.53
45.29
45.07
2.91
16.09
7.69
8.21
11.3
15.69
11.36
33.78
34.6
35.59
38.42
36.09
77.88
70.07
66.5
59.04
34.85
39.89
37.1
29.81
11.31
4.39
8.26
6.1
ID
446
448
450
452
454
470
472
474
476
480
482
484
486
488
490
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
Average (hrs)
5.61
2.07
8.73
12.94
2.38
0.49
0.49
0.41
0.55
947.93
130.78
0.11
588.10
947.93
18.14
62.06
0.16
7.11
95.1
108.24
947.93
93.84
947.93
7.58
947.93
947.93
8.11
13.93
5.64
12
0
6.17
155.01
7.2
20.33
23.77
16.59
5.61
6.3
0.63
7.06
11.19
6.53
ID
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
Average (hrs)
8.26
6.64
6.57
9.37
9.09
8.06
9.44
7.56
5.78
7.12
10.42
9.59
10.82
8.56
7.71
10.54
12.2
11.08
6.31
0.78
8.91
5.99
5.54
5.67
4.38
4.94
4.86
11.25
947.93
4.74
10.28
9.12
5.08
6.25
4.38
7.17
3.98
5.3
4.24
6.25
62.36
9.19
5.27
ID
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
Average (hrs)
0.24
14.53
3.55
9.89
947.93
4.37
1.99
3.36
5.48
10.56
3.82
3.6
947.93
3.54
947.93
15.45
28.45
3.18
2.68
13.68
4
40.09
12.76
0.32
15.78
0.86
23.18
5.46
2.26
947.93
9.96
9.65
2.62
2.84
2.87
3.17
2.49
947.93
2.58
947.93
13.53
0.55
19.15
IDSE Guidance Manual for the Final Stage 2 DBPR F-15
January 2006
-------
MODELING ANALYSIS RESULTS (CONTINUED)
Average Water Age for All Nodes (Hour 936 to Hour 960 of Simulation)
ID
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
Average
(hrs)
7.76
3.33
947.93
3.39
2.96
3.54
3.11
12.42
11.1
947.93
91.17
3.9
4.03
947.93
5.77
33.29
4.15
3.66
4.33
4.38
9.14
0.55
35.4
4.25
4.85
4.42
62.47
4.6
947.93
947.93
4.28
4.93
6.34
6.08
16.55
8.71
4.67
7.07
7.82
7.42
19.91
9.08
0.4
ID
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
Average (hrs)
11.18
11.08
12.28
12.71
9.74
6.69
16.61
7.23
21.24
55.84
4.14
4.01
26.65
11.46
13.53
10.92
15.57
30.07
9
12.33
0.55
947.93
30.74
13.37
34.46
21.7
13.97
29.7
23.94
9.61
8.47
23.68
21.97
21.6
21.85
22
18
22.54
20.72
947.93
33.84
37.03
23.58
ID
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
Average (hrs)
16.11
22.86
24.73
7.42
17.71
4.75
21.63
8.88
947.93
30.85
20.75
24.67
19.74
19.27
16.71
21.05
947.93
18.78
17.59
37.14
10.53
15.7
25.96
28.42
28.09
16.94
15.21
21.73
43.29
11.98
17.13
9.13
17.52
16.95
17.2
16.81
20.4
947.93
947.93
14.17
14.04
62.71
13.92
ID
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
Average (hrs)
947.93
44.19
28.38
20.8
13.59
17.77
15.55
15.21
93.45
334.45
47.35
44.01
73.19
180.69
14.57
13.66
128.65
5.87
5.25
3.38
55.17
947.93
57.91
16.04
15.39
9.4
5.49
10.51
13.76
9.59
28.08
173.08
15.82
183.99
154.62
172.86
35.13
155.92
29.41
8.24
25.69
947.93
947.93
IDSE Guidance Manual for the Final Stage 2 DBPR F-16
January 2006
-------
MODELING ANALYSIS RESULTS (CONTINUED)
Average Water Age for All Nodes (Hour 936 to Hour 960 of Simulation)
ID
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
Average
(hrs)
15.41
13.2
947.93
13.18
947.93
44.01
30.5
10.47
39.4
64.59
90.1
66.63
22.13
69.96
67.85
80.4
61.48
4.7
67.69
64.22
73.64
68.43
28.44
28.17
28.4
30.9
61.1
11.5
14.01
28.05
27.83
43.49
35.48
26.95
27.3
20.57
9.35
60.46
36.99
13.44
67.16
48.75
947.93
ID
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
Average (hrs)
947.93
27.25
12.31
64.6
10.2
35.3
107.16
30.62
947.93
46.6
26.67
6.72
25.72
26.8
9.95
26.07
25.99
25.39
23.62
947.93
947.93
25.09
22.99
23.95
9.39
22.1
947.93
106.7
45.02
947.93
51.76
54.77
48.44
30.27
947.93
27.34
32.52
67.84
38.08
32.98
947.93
34.52
30.84
ID
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
Average (hrs)
36.44
947.93
38.16
47.25
32.22
38.87
31.36
15.1
31.67
32.44
28.03
28.28
31.44
28.46
21.36
28.67
54.41
27.44
13.34
13.05
12.04
947.93
14.01
15.85
31.76
14.79
56.36
16.5
34.68
947.93
20.62
30.51
30.37
947.93
947.93
29.74
30.68
28.82
39.05
1.69
28.82
4.52
28.66
ID
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
Average (hrs)
30.44
15.56
36.91
947.93
20.34
1.71
947.93
21.62
22.44
27.88
27.93
22.1
33.81
1.71
5.35
18.02
5.3
8.3
9.92
18.12
57.1
15.31
18.75
58.41
81.12
65.54
26.22
24.87
26.12
27.32
947.93
2.98
26.42
22.2
10.38
4.93
20.56
20.09
2.8
3.84
6.55
21.22
2.15
IDSE Guidance Manual for the Final Stage 2 DBPR F-l 7
January 2006
-------
MODELING ANALYSIS RESULTS (CONTINUED)
Average Water Age for All Nodes (Hour 936 to Hour 960 of Simulation)
ID
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
Average (hrs)
12.74
1.94
1.83
1.63
1.91
33.73
29.76
947.93
4.96
4.86
5.17
5.39
28.36
7.62
947.93
6.88
9.07
14.69
7.97
14.39
17.08
16.1
11.46
947.93
12.63
35.05
8.09
6.71
34.93
5.47
13.62
26.17
947.93
26.13
26.9
26.12
21.46
29.26
109.84
31.54
90.57
24.39
16.31
ID
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
Average (hrs)
27.28
21.53
15.63
16.98
24.66
947.93
11.1
12.54
26.33
947.93
23.21
947.93
18.48
17.66
17.77
8.21
8.07
6.18
4.67
4.39
4.33
5.45
4.6
4.82
947.93
947.93
6.23
31.31
75.19
1.51
3.88
19.37
324.34
39.59
10.21
947.93
28.04
26.12
947.93
947.93
32.43
318.95
947.93
ID
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
Average (hrs)
2.94
947.93
1.49
1.62
947.93
9.1
7.02
5.53
8.93
5.51
947.93
29.7
7.21
8.33
16.13
21.2
4.41
35.53
18.2
53.95
21.74
18.58
17.41
17.39
20.31
24.61
18.49
33.57
21.88
22.31
27.95
15.85
947.93
18.55
18.16
17.63
21
52.83
947.93
19.81
26.65
26.24
947.93
ID
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
Average (hrs)
17.62
54.87
45.46
11.65
947.93
62.9
44.65
32.05
43.9
3.47
947.93
4.1
229.18
4.68
121.33
28.19
124.75
24.75
17.01
16.78
9.42
74.9
6.61
9.45
9.54
10.05
12.7
10.52
9.56
6.49
51.88
11.17
11
12.65
23.87
30.62
26.81
6.86
6.32
7.54
63.75
11.24
947.93
IDSE Guidance Manual for the Final Stage 2 DBPR F-18
January 2006
-------
MODELING ANALYSIS RESULTS (CONTINUED)
Average Water Age for All Nodes (Hour 936 to Hour 960 of Simulation)
ID
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
Average (hrs)
14.57
11.29
11.45
12.1
11.92
12.35
233.36
947.93
13.44
30.77
30.78
3.38
35.68
14.93
50.93
32.32
33.81
25.23
26.59
25.16
29.32
21.69
41.66
9.53
5.65
19.64
14.9
5.55
5.71
5.14
4.96
947.93
8.48
5.4
4.46
6.13
6.32
5.25
7.75
103.99
4.93
4.64
6.97
ID
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
Average (hrs)
4.33
4.37
4.2
5.36
6.02
5.67
29.71
5.57
5.95
6.27
6.75
6.19
6.48
14.02
14.57
18.25
15.42
5.34
6.78
4.34
6.02
8.44
23.73
5.29
5.87
4.97
4.23
5.17
4.52
3.83
5.99
3.09
3.6
3.33
5.83
3.46
3.19
3.93
18.99
5.16
947.93
2.68
2.37
ID
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
Average
(hrs)
2.6
2.43
2.5
113.62
1.79
20.44
1.47
1.15
5.27
947.93
1.07
2.37
42.65
112.12
947.93
33.5
42.95
116.37
123.36
9.67
117.02
5.31
8.1
947.93
125.05
166.46
100.57
112.85
176.36
169.74
947.93
947.93
IDSE Guidance Manual for the Final Stage 2 DBPR F-19
January 2006
-------
This page intentionally left blank.
IDSE Guidance Manual for the Final Stage 2 DBPR F-20 January 2006
-------
Form 5: IDSE Report for a Modeling SSS pagei om
I. GENERAL INFORMATION
(Skip this section if you are submitting the plan
A.
F
PWS Information*
PWSID:
PWS Name:
PWS Address:
City:
Dopulation Served:
System Type:
B CWS
D NTNCWS
C. PWS Operations
Residual Disinfectant
Number of Disinfected
D.
Contact Person*
Name:
Title:
Phone Number:
E-mail:
US1111111
Big City Water System
1234 Main Street
Big City
57,000
Source Water Type:
H Subpart H
n Ground
Type: H Chlorine n
Sources: 1 Surface
Mr. John Smith, P.E.
and report at the same time)
B. Date Submitted*
2/17/09
State: US Zip: 99999
Buying / Selling Relationships:
n Consecutive System
n Wholesale System
H Neither
Chloramines n Other:
3 GWUDI Ground Purchased
Water System Manager
123-555-0000
jsmith@ci.bigcity.us
Fax: 123-555-0001
II. SSS AND STAGE 2 DBPR REQUIREMENTS*
A.
Number of Required Stage 2 DBPR Com):
3 Hiahest TTHM 2
3 Hiahest HAAS
B.
IDSE Schedule
a Schedule 1
H Schedule 2
a Schedule 3
a Schedule 4
}liance Monitoring Sites 8 TOTAL
Stage 1 DBPR
C. Required Stage 2 DBPR Monitoring Frequency
n Once during peak historical month
H Every 90 days (4 monitoring periods)
D. Number of Required SSS Samples
16 TOTAL
IDSE Guidance Manual for the Final Stage 2 DBPR F-21
January 2006
-------
Form 5: IDSE Report for a Modeling SSS page2ofn
III. MODELING INFORMATION
(Skip this section if you submitted a modeling study plan with an approved model calibration
and your information has not changed, or if you are submitting your plan and report at the
same time)
A.
1.
2.
3.
4.
B.
1.
2.
3.
4.
How was demand data assigned to the model? (attach additional sheets if
needed)
What method was used to assign
demands throughout the system?
How did you estimate diurnal demand
variation? How did you determine
total system demand?
How many demand categories did
you use?
How did you address large water
users?
Describe all calibration activities undertaken* (attach additional sheets if
needed)
When was the model last calibrated?
What types of data were used in the
calibration?
When was the calibration data
collected?
What field tests have been performed
to collect calibration data?
IDSE Guidance Manual for the Final Stage 2 DBPR F-22
January 2006
-------
Form 5: IDSE Report for a Modeling SSS pagesom
III. MODELING INFORMATION (Continued)
5.
6.
7.
8.
How did you determine friction factors
(C-factors)?
Was the calibration completed for the
peak month for TTHM formation? If
not, was the model performance
verified for the peak month for TTHM
formation?
How well do actual tank levels
correlate with predicted tank levels
during the peak month for TTHM
formation?
Submit a graph of predicted tank
levels vs. measured tank levels for
the storage facility with the highest
waterage in each pressure zone*.
If you are using a water quality model,
what parameters are modeled? How
was the model calibrated?
IDSE Guidance Manual for the Final Stage 2 DBPR F-23
January 2006
-------
Form 5: IDSE Report for a Modeling SSS page4ofn
III. MODELING INFORMATION (Continued)
C.
1.
2.
3.
4.
How was the SSS modeling performed?* (attach additional sheets as needed)
Was modeling done for the operating
conditions during the peak month for
TTHM formation*?
How were operational controls
represented in the model?
How was water age simulated during
the peak month for TTHM formation
(time steps, length of simulation,
etc.)?
What are the average water age
results for your distribution system?
Submit final model output showing
24-hour average residence time
throughout the distribution
system*.
Submit graph of water age at the
longest residence time storage
facility in the distribution system
showing the predictions for the
entire EPS simulation period*.
IDSE Guidance Manual for the Final Stage 2 DBPR F-24
January 2006
-------
Form 5: IDSE Report for a Modeling SSS pagesom
IV. SSS MONITORING LOCATION SELECTION
How
1.
2.
3.
4.
5.
were the SSS monitoring locations selected? (attach additional sheets as needed)
What model results were used as the
basis for selection?
What criteria were used in selecting
average residence time, high TTHM,
and high HAAS sites?
What additional data was used in the
analysis, and how was it used?
How did you look at practical
considerations like accessibility of
sampling locations?
How did you verify that your selected
sampling locations corresponded to
the selected node in your model?
The average water age results from the last 24
hours of the 960 hour simulation were analyzed.
Nodes were ranked by age and a histogram of
water age ranges was created.
The high TTHM and high HAAS sites were selected
with water ages in the range of 300 - 500 hours.
These were the high results from the modeling
(excluding zero demand nodes). The average
water age was determined to be 20 hours based on
the most frequently occurring age in the histogram.
TCR data for chlorine residual was examined for
each potential sampling site. High water age
locations with measurable residual were selected
for high HAAS sites. High water age locations with
low residual chlorine were selected for high TTHM
sites.
Once model nodes were identified, the proposed
location was found on the paper water atlas sheets
and an accessible sampling point was determined
in the vicinity of the original node. Accessible
locations served by the same water main as the
model node were targeted. If the targeted water
main was not accessible, an alternate location on a
water main of the same diameter was found in the
vicinity.
Using the paper water atlas sheets and comparing
the locations to the information in the hydraulic
model, locations were verified.
IDSE Guidance Manual for the Final Stage 2 DBPR F-25
January 2006
-------
Form 5: IDSE Report for a Modeling SSS pageeom
V. SSS AND STAGE 1 DBPR MONITORING RESULTS*
A. 1
FTHM Results
Site ID &
Category
Stage 1 Site 1
Stage 1 Site 2
Stage 1 Site 3
Stage 1 Site 4
SSS-1
Entry
SSS-2
Average
SSS-3
Average
SSS-4
Average
SSS-5
Average
SSS-6
High TTHM
SSS-7
High TTHM
SSS-8
High TTHM
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
TTHM (mg/L)
3/12/08
0.041
3/12/08
0.045
3/12/08
0.051
3/12/08
0.048
6/7/08
0.048
6/7/08
0.046
6/7/08
0.055
6/7/08
0.052
8/22/08
0.062
8/22/08
0.058
8/22/08
0.075
8/22/08
0.068
8/5/08
0.028
8/5/08
0.048
8/5/08
0.058
8/5/08
0.067
8/5/08
0.033
8/5/08
0.056
8/5/08
0.059
8/5/08
0.055
10/1/08
0.050
10/1/08
0.053
10/1/08
0.059
10/1/08
0.053
LRAA
0.050
0.051
0.060
0.055
0.028
0.048
0.058
0.067
0.033
0.056
0.059
0.055
Attach additional sheets as needed for SSS and Stage 1 DBPR results.
IDSE Guidance Manual for the Final Stage 2 DBPR F-26
January 2006
-------
Form 5: IDSE Report for a Modeling SSS page7ofn
V. SSS AND STAGE 1 DBPR MONITORING RESULTS* (Continued)
B. h
HAAS Results
Site ID &
Category
Stage 1 Site 1
Stage 1 Site 2
Stage 1 Site 3
Stage 1 Site 4
SSS-1
Entry
SSS-2
Average
SSS-3
Average
SSS-4
Average
SSS-5
Average
SSS-6
High TTHM
SSS-7
High TTHM
SSS-8
High TTHM
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
HAAS (mg/L)
3/12/08
0.034
3/12/08
0.030
3/12/08
0.032
3/12/08
0.040
6/7/08
0.046
6/7/08
0.045
6/7/08
0.038
6/7/08
0.004
8/22/08
0.006
8/22/08
0.044
8/22/08
0.037
8/22/08
0.012
8/5/08
0.018
8/5/08
0.020
8/5/08
0.019
8/5/08
0.026
8/5/08
0.033
8/5/08
0.048
8/5/08
0.057
8/5/08
0.046
10/1/08
0.042
10/1/08
0.042
10/1/08
0.040
10/1/08
0.044
LRAA
0.032
0.040
0.037
0.025
0.018
0.020
0.019
0.026
0.033
0.048
0.055
0.046
Attach additional sheets as needed for SSS and Stage 1 DBPR results.
IDSE Guidance Manual for the Final Stage 2 DBPR F-2 7
January 2006
-------
Form 5: IDSE Report for a Modeling SSS pagesorn
V. SSS AND STAGE 1 DBPR MONITORING RESULTS* (Continued)
C. Where were your TTHM and HAAf
H In-House
Is your in-house laboratory c
D Certified Laboratory
Name of certified laboratory:
> samples analyzed?
ertified? is Yes n No
D. What method(s) was used to analyze your TTHM and HAAS samples?
TTHM HAAS
B EPA 502.2 H EPA 552.1 D EPA 552.2
D EPA 524.2 D EPA 552.3 D SM 6251 B
D EPA 551.1
VI. SELECTION OF STAGE 2 DBPR COMPLIANCE MONITORING LOCATIONS
Desc
neec
1.
2.
3.
4.
;ribe the comparison of sampling and modeling results (attach additional sheets as
led):
How well did the sampling results
correspond to the modeling results?
For samples that did not match well
with model results, what follow-up
investigations were performed?
Were additional samples collected?
(Include data on table in section IV)
Submit a graph of water age
versus time for each selected
sampling location*.
For most SSS monitoring sites, the results were in
accordance with the modeling results.
Discrepancies were found at 2 sites: SSS-4 and
SSS-1 1 . SSS-4 was an average residence time
site with TTHM results that were more typical of a
high TTHM site. SSS-1 1 was a high TTHM site
with TTHM results that were more typical of an
average site.
At sites SSS-4 and SSS-1 1 , data for chlorine
residual was reviewed from TCR sampling. The
time of sample collection was compared to the
water age graph. The model results for water age
at SSS-1 1 are highly variable and therefore that
site was eliminated from further consideration. The
discrepancy at SSS-4 could have been related to
variation overtime, although the model results are
less conclusive at that site. SSS-4 was also
eliminated from further consideration.
No
Graphs are attached.
IDSE Guidance Manual for the Final Stage 2 DBPR F-28
January 2006
-------
Form 5: IDSE Report for a Modeling SSS page9ofn
VII. JUSTIFICATION OF STAGE 2 DBPR COMPLIANCE MONITORING SITES*
Compliance
Monitoring
Site ID
Stage 2 Site 1
Stage 2 Site 2
Stage 2 Site 3
Stage 2 Site 4
Stage 2 Site 5
Stage 2 Site 6
Stage 2 Site 7
Stage 2 Site 8
Site Type
EI Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
EI Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
EI Stage 1 DBPR
H Highest TTHM
D Highest HAAS
D Stage 1 DBPR
H Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
EI Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
EI Stage 1 DBPR
D Highest TTHM
EI Highest HAAS
D Stage 1 DBPR
Justification
SSS-12
High average water age, high TTHM results during
monitoring, located in East Pressure Zone
SSS-14
High average water age, high HAAS results during
monitoring, measurable residual in historical TCR
data, located in East Pressure Zone
Stage 1 Site 2
Average residence time Stage 1 DBPR site with
high HAAS LRAA, relatively high water age, located
in East Pressure Zone
SSS-9
High average water age, high TTHM results during
monitoring, located in East Pressure Zone
SSS-15
High average water age, high TTHM results during
monitoring, located in East Pressure Zone
SSS-10
High average water age, high HAAS results during
monitoring, measurable residual in historical TCR
data, located in Central Pressure Zone
Stage 1 Site 4
High average water age, high TTHM historical data,
located in West Pressure Zone
SSS-13
High average water age, high HAAS results during
monitoring, measurable residual in historical TCR
data, located in East Pressure Zone
Attach additional copies of this sheet if you need more room.
IDSE Guidance Manual for the Final Stage 2 DBPR F-29
January 2006
-------
Form 5: IDSE Report for a Modeling SSS pageioom
VIM. PEAK HISTORICAL MONTH
A.
B.
Peak Historical Month* Auqust
Is Your Peak Historical Month the Same as your Peak Month for TTHM
Formation in your Model Study Plan?
H Yes D No
If no, explain how you selected your new peak month for TTHM formation
(attach additional sheets if needed):
IX. PROPOSED STAGE 2 COMPLIANCE MONITORING SCHEDULE*
Stage 2
Compliance
Monitoring
Site ID
Stage 2 Site 1
Stage 2 Site 2
Stage 2 Site 3
Stage 2 Site 4
Stage 2 Site 5
Stage 2 Site 6
Stage 2 Site 7
Stage 2 Site 8
Projected Sampling Date (date or week)1
period 1
11/2012, wk1
11/2012, wk1
11/2012, wk1
11/2012, wk1
11/2012, wk1
11/2012, wk1
11/2012, wk1
11/2012, wk1
period 2
2/2013, wk1
2/2013, wk1
2/2013, wk1
2/2013, wk1
2/2013, wk1
2/2013, wk1
2/2013, wk1
2/2013, wk1
period 3 period 4
5/2013, wk1 8/2013, wk 1
5/2013, wk1 8/2013, wk 1
5/2013, wk1 8/2013, wk 1
5/2013, wk1 8/2013, wk 1
5/2013, wk1 8/2013, wk 1
5/2013, wk1 8/2013, wk 1
5/2013, wk1 8/2013, wk 1
5/2013, wk1 8/2013, wk 1
1 period = monitoring period. Complete for the number of monitoring periods from
Section II. C.
Attach additional copies of this sheet if you need more room.
IDSE Guidance Manual for the Final Stage 2 DBPR F-30
January 2006
-------
Form 5: IDSE Report for a Modeling SSS
X. DISTRIBUTION SYSTEM SCHEMATIC*
(Skip this section if you submitted a modeling study plan and your distribution system
schematic was complete and has not changed from your approved modeling study plan, or if
you are submitting the plan and report at the same time)
ATTACH a schematic of your distribution system. If your schematic has changed or if
you did not show your SSS monitoring locations on the distribution system schematic
you submitted with your model study plan (Form 4), you must submit a revised
distribution system schematic.
XI. ATTACHMENTS
D Tabular or spreadsheet documentation that your model meets minimum calibration
requirements if updated since approved modeling study plan* (Section III).
D Additional sheets for explaining model information/results, including required graphs if
not submitted as part of an approved modeling study plan* (Section III).
is Additional sheets for sampling results, if needed (Section V).
is Additional sheets for selection of Stage 2 DBPR compliance monitoring sites (Section
VI).
is Graph of water age versus time for all Stage 2 DBPR sites selected* (Section VI).
D Additional sheets for justification of Stage 2 DBPR Monitoring Sites, if needed
(Section VII). REQUIRED if you are a subpart H system serving more than
249,999 people.
D Additional sheets for explaining how you selected the peak historical month (Section
VIII).
D Additional sheets for proposed compliance monitoring schedule (Section IX).
REQUIRED if you are a subpart H system serving more than 249,999 people.
D Explanation of deviations from approved study plan.
H Distribution system schematic* (Section X). REQUIRED if it has changed from
your approved model study plan or if monitoring locations were not shown.
D Compliance calculation procedures (for Stage 2 Compliance Monitoring Plan).
Total Number of Pages in Your Report: 25
Note: All items marked with an asterisk (*) are required by the rule.
IDSE Guidance Manual for the Final Stage 2 DBPR F-31 January 2006
-------
This page intentionally left blank.
IDSE Guidance Manual for the Final Stage 2 DBPR F-32 January 2006
-------
Distribution System Schematic
Modeling SSS Report
Central Pressure Zone
Vtest Pressure Zone
Stage 2 Site 2
SS-8
Legend
^^^^^^— Pressure Zone Boundary
Distribution mains
DIANE IE R
2-S
10-30
Facility
'\~s Pump Station
Q M.
Ab Water Tteatment Plant
A Stage 1 DBPR Locations
* SSS Sites
Scale 1:8,000
IDSE Guidance Manual for the Final Stage 2 DBPR F-33
January 2006
-------
SSS MONITORING LOCATION SELECTION
Histogram of Water Age Results
Average Age = midpoint of most frequently occurring range
= midpoint of 20 - 40 hour range = 30 hours
Percentage of nodes
60 i
50
40
30-
20
10-
oooooooooooooooooooooooooooooooooooo
CN^CDOOOCN^CDOOOCN^CDOO" .-_--_-. .._____. .,_.__.. .,_.__
^-^-^-^-^-CNCNCNf'"'
OCN^CDOOOCN^CDOOOCN^CDOOOCN^CDOOO i;
cococococo^^^^-^-ininininincDCDCDCDCDt^°
Time (hours)
IDSE Guidance Manual for the Final Stage 2 DBPR F-34
January 2006
-------
SSS MONITORING LOCATION SELECTION (CONTINUED)
Average Water Age Results for SSS monitoring locations
(Hour 936 to Hour 960 of Simulation)
Node
1411
1362
1336
1639
1640
276
1533
144
18
174
486
122
120
106
162
86
Average Water Age (hrs)
1.69
30.27
30.62
30.77
30.78
280.49
324.34
497.02
581.18
587.53
588.10
288.94
331.35
333.21
491.68
579.20
Preliminary Category
Entry
Average
Average
Average
Average
High TTHM
High TTHM
High TTHM
High TTHM
High TTHM
High TTHM
High HAAS
High HAAS
High HAAS
High HAAS
High HAAS
ID
SSS-1
SSS-2
SSS-3
SSS-4
SSS-5
SSS-6
SSS-7
SSS-8
SSS-9
SSS-10
SSS-11
SSS-12
SSS-13
SSS-14
SSS-15
SSS-16
IDSE Guidance Manual for the Final Stage 2 DBPR F-35
January 2006
-------
SSS MONITORING LOCATION SELECTION (CONTINUED)
Selection of Stage 2 DBPR Compliance Monitoring Sites
SSS Sites
SSS-1
SSS-2
SSS-3
SSS-4
SSS-5
SSS-6
SSS-7
SSS-8
SSS-9
SSS-10
SSS-11
SSS-12
SSS-13
SSS-14
SSS-15
SSS-16
Stage 1,
Site 1
Stage 1,
Site 2
Stage 1,
SiteS
Stage 1,
Site 4
TTHM
LRAA
Results
0.028
0.048
0.058
0.067
0.033
0.056
0.059
0.055
0.068
0.064
0.043
0.073
0.061
0.069
0.064
0.048
0.050
0.051
0.060
0.055
TTHM
Rank*
20
17
10
4
19
11
9
12
3
6
18
1
7
2
5
16
15
14
8
13
HAAS
LRAA
Results
0.018
0.020
0.019
0.026
0.033
0.048
0.055
0.046
0.029
0.057
0.030
0.050
0.052
0.060
0.058
0.046
0.032
0.040
0.037
0.025
HAAS
Rank*
20
18
19
16
12
7
3
8
15
4
14
6
5
1
2
9
13
10
11
17
Preliminary
Category
Entry
Average
Average
Average
Average
High TTHM
High TTHM
High TTHM
High TTHM
High TTHM
High TTHM
High HAA5
High HAA5
High HAA5
High HAA5
High HAA5
Stage 1
Stage 1
Stage 1
Stage 1
Water
Age
1.69
30.27
30.62
30.77
30.78
280.49
324.34
497.02
581.18
587.53
588.10
288.94
331.35
333.21
491.68
579.20
203.22
31.05
423.44
496.81
Zone
Central
Central
Central
Central
West
East
East
East
East
Central
East
East
East
East
East
East
East
East
East
West
Stage 2
DBPR
Selected
Sites
Rejected
Site 4
Site 6
Rejected
Site 1
SiteS
Site 2
Site 5
Site 3
Site 7
Stage 2 DBPR Site Type
TTHM
HAA5
TTHM
HAA5
HAA5
TTHM
Stage 1
Stage 1 - Not highest but representative
high site and located in West zone
*Ranked from highest(l) to lowest (20)
IDSE Guidance Manual for the Final Stage 2 DBPR
F-36
January 2006
-------
SSS MONITORING LOCATION SELECTION (CONTINUED)
WATERAGE RESULTS GRAPHS
Site A
900
800 -
100
-Water Age ^»- - Average Water Age
IDSE Guidance Manual for the Final Stage 2 DBPR F-3 7
January 2006
-------
STAGE 2 DBPR MONITORING LOCATIONS
WATER AGE RESULTS
Site B
900
800 -
-Water Age ^m- - Average Water Age
IDSE Guidance Manual for the Final Stage 2 DBPR F-38
January 2006
-------
STAGE 2 DBPR MONITORING LOCATIONS
WATERAGE RESULTS (CONTINUED)
SiteC
900
-Water Age ^m- - Average Water Age
800 -
700 -
600 -
500 -
5 400 -
i
300 :
200 -
100 -
12
Time (hrs)
18
IDSE Guidance Manual for the Final Stage 2 DBPR F-39
January 2006
-------
STAGE 2 DBPR MONITORING LOCATIONS
WATERAGE RESULTS (CONTINUED)
500
Site D
-Water Age
- Average Water Age
450 -
400 -
350 -
300 -
(1)
m 250 -
200 -
150 -
100 -
50 -
12
Time (hrs)
18
24
IDSE Guidance Manual for the Final Stage 2 DBPR F-40
January 2006
-------
STAGE 2 DBPR MONITORING LOCATIONS
WATERAGE RESULTS (CONTINUED)
Site E
900
800 -
-Water Age •
- Average Water Age
IDSE Guidance Manual for the Final Stage 2 DBPR F-41
January 2006
-------
STAGE 2 DBPR MONITORING LOCATIONS
WATERAGE RESULTS (CONTINUED)
Site F
900
800 -
700 -
600 -
500 -
01 400 -
300 -
200 -
100 -
-Water Age •
- Average Water Age
IDSE Guidance Manual for the Final Stage 2 DBPR F-42
January 2006
-------
STAGE 2 DBPR MONITORING LOCATIONS
WATERAGE RESULTS (CONTINUED)
SiteG
900
800
-Water Age •
- Average Water Age
IDSE Guidance Manual for the Final Stage 2 DBPR F-43
January 2006
-------
STAGE 2 DBPR MONITORING LOCATIONS
WATERAGE RESULTS (CONTINUED)
Site H
900
-Water Age ^»- - Average Water Age
800 -
700 -
600 -
500 -
5 400 -
300 -
200 -
100 n
12
Time (hrs)
18
24
IDSE Guidance Manual for the Final Stage 2 DBPR F-44
January 2006
-------
MONITORING RESULTS -ADDITIONAL SHEETS
Form 5: IDSE Report for a Modeling SSS
V. SSS AND STAGE 1 DBPR COMPLIANCE MONITORING RESULTS
A. 1
FTHM Results*
Site ID
SSS-9
High TTHM
SSS-10
High TTHM
SSS-1 1
High TTHM
SSS-1 2
High HAAS
SSS-1 3
High HAAS
SSS-1 4
High HAAS
SSS-1 5
High HAAS
SSS-1 6
High HAAS
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
TTHM (mg/L)
8/6/08
0.068
8/6/08
0.064
8/6/08
0.043
8/6/08
0.073
8/6/08
0.061
8/6/08
0.069
8/6/08
0.064
8/6/08
0.048
LRAA
0.068
0.064
0.043
0.073
0.061
0.069
0.064
0.048
Attach additional sheets as needed for SSS and Stage 1 DBPR results.
IDSE Guidance Manual for the Final Stage 2 DBPR F-45
January 2006
-------
MONITORING RESULTS -ADDITIONAL SHEETS
Form 5: IDSE Report for a Modeling SSS
V. SSS AND STAGE 1 DBPR COMPLIANCE MONITORING RESULTS
A. h
HAA5 Results*
Site ID
SSS-9
High TTHM
SSS-10
High TTHM
SSS-1 1
High TTHM
SSS-1 2
High HAAS
SSS-1 3
High HAAS
SSS-1 4
High HAAS
SSS-1 5
High HAAS
SSS-1 6
High HAAS
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
HAAS (mg/L)
8/6/08
0.029
8/6/08
0.057
8/6/08
0.030
8/6/08
0.050
8/6/08
0.052
8/6/08
0.060
8/6/08
0.058
8/6/08
0.046
LRAA
0.029
0.057
0.030
0.050
0.052
0.060
0.058
0.046
Attach additional sheets as needed for SSS and Stage 1 DBPR results.
IDSE Guidance Manual for the Final Stage 2 DBPR F-46
January 2006
-------
Appendix G
Complex Modeling Analysis Example for a System
with Multiple Sources
-------
This page intentionally left blank.
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Complex Modeling Analysis Example for a System with Multiple Sources
Chapter 6 discussed modeling in general terms and the example included in Section 6.2.2
is applicable to systems with a single water source or multiple sources with similar water quality
in terms of initial DBF concentrations and DBF formation potentials. However, some systems
may have multiple sources with very different water quality characteristics. For example, a
system may be served by both a groundwater source with low DBF precursor concentrations and
a surface water source with high DBF precursor concentrations. For these special cases, a
simple water age simulation will not capture the true variation in DBF concentrations because it
does not distinguish between the different quality source waters. A high water age for the low
DBF source may not result in a high DBF concentration. For example, in this case study the low
DBF precursor source has a TTHM formation potential of 0.022 mg/L and the high DBF
precursor source has a TTFDVI formation potential of 0.122 mg/L. Very old water from the low
DBF precursor source may have a TTFDVI concentration on the order of 0.020 mg/L while
relatively fresh water from the high DBF precursor source could have a TTFDVI concentration
greater than 0.100 mg/L. Similar situations arise in consecutive systems where the water age
entering the distribution system is different at different entry points.
Most modeling software that is currently available cannot apply a source-specific
formation rate coefficient. The formation rate coefficient is currently specified as a single,
globally-applied parameter. Special provisions should be made when using models to analyze
systems with multiple sources of varying water quality. A source-adjusted water age can be
calculated or an estimate of maximum possible DBF concentration can be developed. These are
illustrated in the following example.
Systems in this category should submit additional documentation that describes their
modeling procedures and analysis for selection of SSS monitoring sites.
Source-Adjusted Water Age Analysis
The system schematic is shown in Exhibit G. 1. If the two sources in this example have
very different DBF formation rates and ultimate formation potentials, then a simple water age
analysis as performed in Section 6.2.2 will not necessarily identify the locations with highest
DBF levels. For example, if the water in Tank 3 comes mostly from the RIVER source and this
source has a much lower DBF formation potential than the LAKE source, then this tank may no
longer contain water with the highest DBF concentration, even though it has the oldest water in
the system.
Ideally, one would like to account for both the individual DBF formation potential and
kinetics for each source water as well as the blending of these waters together in an integrated
fashion when simulating the system. Unfortunately, the current generation of network water
quality models is not capable of directly performing this kind of analysis. However, one can
perform a series of simulations and calculations to approximately account for significant
differences in DBF production between different source waters.
IDSE Guidance Manual for the Final Stage 2 DBPR G-l January 2006
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Exhibit G.1 Schematic of the Case Study Distribution System
RIVER Source
Calculating a source-adjusted water age for this case study requires a source trace
analysis and data on the ultimate DBF formation potential (maximum concentration) for each
source. The first step is to calculate the percentage of water from each source for all nodes in the
system. These values can be obtained by changing the type of water quality analysis from AGE
to TRACE, selecting the LAKE source as the source to be traced, and re-running the simulation.
Exhibit G.2 displays the average percentage of water from the LAKE source reaching each node.
The percentage from the RIVER source at any node would simply be 100 minus the LAKE
percentage. Note how the nodes on the left side of the network receive mainly LAKE water
while the nodes in the upper right, which had the oldest water in the example in Section 6.2.2,
receive the least amount of LAKE water.
IDSE Guidance Manual for the Final Stage 2 DBPR G-2
January 2006
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Exhibit G.2 Average Percentage of Water From the LAKE Source
LAKE Source
131
243
The adjusted water age for each node of the system can be calculated as a weighted
average by using the following equation:
Adjusted Age = Age * (PLAKE + PMVER / R) /100
where Age = the original age estimate,
LAKE
RIVER
= percentage of LAKE water,
= percentage of RIVER water, and
R = ratio of LAKE DBF formation potential to RIVER DBF formation potential.
A similar version of this equation can be used with more than two sources by including
all sources in the weighted average.
In this case, a review of historical data showed that R was equal to 5.5, i.e. the LAKE
source has the potential to form 5.5 times greater DBF concentrations than the RIVER source.
Exporting both the age results and the source tracing results from the model into a spreadsheet
and applying the formula shown above gives the resulting source-adjusted water age throughout
the network, as shown in Exhibit G.3. Comparing these results with the unadjusted ages in
Section 6.2.2 shows a similar pattern in terms of which nodes have the highest ages but a much
IDSE Guidance Manual for the Final Stage 2 DBPR G-3
January 2006
-------
lower adjusted water age overall. This demonstrates that the RIVER water remains in the system
the longest but has much lower potential to form DBFs than the LAKE water. The results of the
adjusted water age analysis demonstrate the importance of considering different sources. For
example, node 131, which was predicted to have the second highest water age in the simple
water age analysis, has an adjusted water age of only 22.5 hours.
Exhibit G.3 Source-Adjusted Water Age Throughout the Study Area
RIVER
LAKE
Rather than using water age as the basis for selecting sampling sites, another option
would be to model DBF formation and thereby directly identify locations with high levels of
DBFs. The required input data for each DBF of interest (i.e., each chemical species) and for
each water source must be available:
1. the DBF concentration leaving the treatment plant
2. a first-order rate constant based on laboratory tests
3. an ultimate formation potential (maximum concentration) of the DBF
Exhibit G.4 lists the values of these parameters for TTHM for the case study. Note the
large difference in the formation potential and formation rate coefficient between the two
sources.
IDSE Guidance Manual for the Final Stage 2 DBPR G-4
January 2006
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Exhibit G.4 Total THM Growth Parameters for the Case Study Example
Total THM at Distribution System
Entry Point (mg/L)
Total THM Formation Potential, F
(mg/L)
First-Order Growth Constant, k
(1/davs)
RIVER
Source
0.012
0.022
2.3
LAKE Source
0.108
0.122
15.1
These parameters are normally used in the following THM growth expression that is
applied system-wide:
C = Co + (F - Co)(l - exp(-kt))
where C = TTHM concentration (mg/L),
Co = initial TTHM concentration leaving the source (mg/L),
F = ultimate TTHM formation (mg/L),
k = growth constant (I/days), and
t = time in days
exp = natural log, e.
Because there are two distinctly different THM sources in this example, the above
equation cannot be applied directly. Instead, as was done for the adjusted water age analysis, a
separate THM growth simulation should be made for each individual source with the results of
each combined outside of the model according to the percent of water from each source. Or, to
simulate a worst case scenario, a DBF simulation could be made using the appropriate source
concentrations for each source but using the highest values for F and k for the global formation
equation. The results from this worst-case simulation are given in Exhibit G.5. The results for
the DBF modeling are quite different from the results for the water age analysis at certain nodes,
as shown in Exhibit G.6.
The results for this case study depend greatly on the system configuration and the
operational conditions. This is a simple representation of a distribution system and does not
reflect the level of complexity that is present in real systems. However, this example does
illustrate the difficulty in predicting water age or DBF concentrations for systems with multiple
sources with varying water quality characteristics.
IDSE Guidance Manual for the Final Stage 2 DBPR G-5
January 2006
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Exhibit G.5 Maximum Possible TTHM Simulation Results
RIVER
LAKE
243
IDSE Guidance Manual for the Final Stage 2 DBPR G-6
January 2006
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Exhibit G.6 Summary of Results from Different Analyses
Node ID
10
15
20
35
40
50
60
601
61
101
103
105
107
109
111
113
115
117
119
120
121
123
125
127
129
131
139
141
143
145
147
149
151
153
157
159
161
163
164
166
167
169
171
173
177
179
Average
Water Age
hours
0.03
72.89
114.22
14.9
31.35
46.22
0.08
0.8
0.21
8.33
6.28
9.06
9.91
9.86
8.69
9.68
9.47
9.16
11.56
10.69
10.93
3.39
67.79
108.72
113.89
135.44
108.63
97.77
76.02
32.38
24.66
30.58
39.84
70.11
10.68
10.54
10.75
10.75
20.74
42.97
11.3
11.16
11.39
11.38
22.1
25.41
Source Adjusted
Water Age
hours
0.03
12.67
19
4.53
17.63
20.49
0.01
0.13
0.04
5.85
5.21
6.15
7.7
7.29
6.11
6.49
6.03
5.88
2.41
5.91
1.83
0.57
11.3
18.09
18.95
22.53
18.07
16.46
13.18
5.92
4.67
5.88
7.4
11.7
2.23
2.19
2.31
2.31
4.28
8.85
2.53
2.5
2.56
2.55
13.43
16.16
Max. THM
formation
ug/l
108.00
12.79
11.91
27.86
57.59
43.86
12.00
12.00
12.00
73.77
88.52
71.02
82.53
78.01
73.90
70.14
66.19
66.86
16.86
56.55
12.08
12.00
11.99
11.92
11.91
11.90
11.92
12.16
12.76
13.87
14.65
14.96
14.19
12.02
16.84
16.73
17.60
17.59
16.57
16.51
18.64
18.66
18.67
18.64
62.77
66.04
IDSE Guidance Manual for the Final Stage 2 DBPR G-7
January 2006
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181
183
184
185
187
189
191
193
195
197
199
201
203
204
205
206
207
208
209
211
213
215
217
219
225
229
231
237
239
241
243
247
249
251
253
255
257
259
261
263
265
267
269
271
273
275
River Source
Lake Source
Tankl
Tank 2
TankS
14.87
19.29
15.85
15.68
10.59
11.59
10.09
9.58
10.06
12.26
11.34
11.32
11.38
10.3
15.51
15.29
15.17
15.62
14.98
14.7
15.32
22.64
24.55
33.48
34.01
19.75
31.31
19.98
25.77
28.85
78.49
30.62
28.14
41.28
46.92
43.68
9.85
9.6
9.09
9.14
10.82
10.36
11.13
11.14
10.74
10.39
0
0
75.35
122.41
189.26
4.52
12.76
10.53
10.45
7.12
7.37
6.67
6.03
6.26
8.72
2.54
2.58
2.58
6.95
10.46
9.2
9.14
9.39
9.27
9.47
9.56
13.76
14.76
19.68
20.14
12.01
18.81
12.13
14.89
16.34
44.19
17.24
16.17
20.12
22.56
21.09
5.99
6.06
5.87
5.94
2.42
6.44
4.19
2.7
3.42
3.55
0
0
25.63
35.84
31.48
27.83
68.97
69.40
69.55
70.29
66.08
68.98
65.33
64.62
74.89
18.56
19.02
18.98
70.65
70.47
62.13
62.24
62.07
64.12
66.99
64.75
62.86
62.10
60.53
61.03
62.84
62.02
62.75
59.38
58.05
57.66
57.66
59.02
48.96
48.17
48.41
62.94
65.60
67.24
67.76
18.58
64.48
36.21
20.71
29.46
32.22
12.00
108.00
31.97
26.50
11.85
IDSE Guidance Manual for the Final Stage 2 DBPR G-8
January 2006
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Appendix H
Example IDSE Standard Monitoring Plan and Report for
a Surface Water System Serving 160,000 People
This appendix provides an example IDSE standard monitoring plan and report for a
surface water system serving 160,000 people. For this example, the state did not require any
modifications to the standard monitoring plan.
Chapter 7 discusses the standard monitoring plan, conducting standard monitoring,
selection of Stage 2 DBPR sites, and preparing the IDSE report. The application of the basic
guidance on standard monitoring location selection and Stage 2 DBPR compliance monitoring
location selection is shown in this example.
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Form 6: Standard Monitoring Plan pageiofe
I. GENERAL INFORMATION
A. PWS Information*
PWSID: US1111111
PWS Name: Elm City
PWS Address: 1234 Main Street
| B. Date Submitted* Sept 15. 2006
City: Elm City State: US Zip: 99999
Population Served: 160,000
System Type: Source Water Type:
H CWS H Subpart H
D NTNCWS D Ground
C. PWS Operations
Residual Disinfectant Type: H Chlorine n Cl
Number of Disinfected Sources: 2 Surface
Buying / Selling Relationships:
n Consecutive System
n Wholesale System
H Neither
iloramines n Other:
GWUDI Ground Purchased
D. Contact Person*
Name: Mr. Ronald Doe, P.E.
Title: Water System Superintendent
Phone #: 123-555-0000
E-mail: Rdoe@ci.elmcity.us
II. IDSE REQUIREMENTS*
A. Number of Sites B. Schedule C
Total: 16
Near Entry Point: 3 H Schedule 1
Avg Residence Time: 4 n Schedule 2
High TTHM: 5 D Schedule 3
High HAAS: 4 D Schedule 4
Fax#: 123-555-0001
. Standard Monitoring Frequency
n During peak historical month
(1 monitoring period)
n Every 90 days (4 monitoring periods)
H Every 60 days (6 monitoring periods)
IDSE Guidance Manual for the Final Stage 2 DBPR H-l
January 2006
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Form 6: Standard Monitoring Plan page2of6
III. SELECTING STANDARD MONITORING SITES
A. I
eac
B.
mo
Data Evaluated Put a "/" in each box corresponding to the data that you used to select
h type of standard monitoring site. Check all that apply.
Data Type
Type of Site
Near
Entry Pt.
Avg. Residence
Time
High
TTHM
High
HAAS
System Configuration
Pipe layout, locations of storage facilities
Locations of sources and consecutive
system entry points
Pressure zones
Information on population density
Locations of large customers
/
/
/
/
/
/
/
/
/
Water Quality and Operational Data
Disinfectant residual data
Stage 1 DBP data
Other DBP data
Microbiological monitoring data (e.g., HPC)
Tank level data, pump run times
Customer billing records
/
/
/
/
/
/
/
/
/
/
/
/
/
Advanced Tools
Water distribution system model
Tracer study
Summary of Data* Provide a summary of data you relied on to justify standard
nitoring site selection, (attach additional sheets if needed)
Both plants operate year round. We used residual and HPC data from Total Coliform sites collected
from 2003 through 2005 with our current system map to select sites. We evaluated chlorine residual
data from June and July (range from 0.2 - 2.3 mg/L), and calculated our system average (1-1.2
mg/L). We looked for sites with levels close to this average for average residence time sites,
although we used HPC data, water age estimates, and pipe data to determine the cause of low
residuals. We have estimated our high water age in the distribution system to be near 5 days. We
relied on tank and residual data to select high TTHM sites. For high HAA5 sites, we also evaluated
HPC data to eliminate areas of suspected biological activity, and Stage 1 sites as a reference point.
We plotted all of our candidate sites on our map to ensure that they are geographically and
hydraulically diverse.
IDSE Guidance Manual for the Final Stage 2 DBPR H-2
January 2006
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Form 6: Standard Monitoring Plan pages ore
IV. JUSTIFICATION OF STANDARD MONITORING SITES*
Standard
Monitoring
Site ID
(from map)1
Standard
Monitoring #1
Standard
Monitoring #2
Standard
Monitoring #3
Standard
Monitoring #4
Standard
Monitoring #5
Standard
Monitoring #6
Standard
Monitoring #7
Standard
Monitoring #8
Site Type
H Near Entry Pt
n Avg. Res. Time
D High TTHM
D High HAAS
H Near Entry Pt
n Avg. Res. Time
D High TTHM
D High HAAS
n Near Entry Pt
H Avg. Res. Time
D High TTHM
D High HAAS
n Near Entry Pt
H Avg. Res. Time
D High TTHM
D High HAAS
n Near Entry Pt
H Avg. Res. Time
D High TTHM
D High HAAS
n Near Entry Pt
H Avg. Res. Time
D High TTHM
D High HAAS
n Near Entry Pt
n Avg. Res. Time
D High TTHM
H High HAAS
n Near Entry Pt
n Avg. Res. Time
D High TTHM
H High HAAS
Justification
See attached sheets.
See attached sheets.
See attached sheets.
See attached sheets.
See attached sheets.
See attached sheets.
See attached sheets.
See attached sheets.
1 Verify that site IDs match IDs in Section IV and on your distribution system schematic (See
Section VII of this form). Attach additional copies if you are required to select more than 8
standard monitoring locations or need more room.
IDSE Guidance Manual for the Final Stage 2 DBPR H-3
January 2006
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Form 6: Standard Monitoring Plan
Page 4 of 6
V. PEAK HISTORICAL MONTH AND PROPOSED STANDARD MONITORING SCHEDULE
A. Peak Historical Month* July
B. If Multiple Sources, Source Used to Determine Peak Historical Month
(write "N/A" if only one source in your system)
Both Hardwood WTP and Softwood WTP had same peak historical month based on Stage 1 TTHM data.
C. Peak Historical Month Based On* (check all that apply)
H High TTHM n Warmest water temperature
n High HAAS
If you used other information to select your peak historical month, explain here
(attach additional sheets if needed)
D. Proposed Standard Monitoring Schedule*
Standard Monitoring
Site ID
(from map) 1
SM#1
SM#2
SM#3
SM#4
SM#5
SM#6
SM#7
SM#8
Projected Sampling Date (date or week)2
period 1
11/2007, wk 2
11/2007, wk 2
11/2007, wk 2
11/2007, wk 2
11/2007, wk 2
11/2007, wk 2
11/2007, wk 2
11/2007, wk 2
period 2
1/2008, wk 2
1/2008, wk 2
1/2008, wk 2
1/2008, wk 2
1/2008, wk 2
1/2008, wk 2
1/2008, wk 2
1/2008, wk 2
period 3
3/2008, wk 2
3/2008, wk 2
3/2008, wk 2
3/2008, wk 2
3/2008, wk 2
3/2008, wk 2
3/2008, wk 2
3/2008, wk 2
period 4
5/2008, wk 2
5/2008, wk 2
5/2008, wk 2
5/2008, wk 2
5/2008, wk 2
5/2008, wk 2
5/2008, wk 2
5/2008, wk 2
period 5
7/2008, wk 2
7/2008, wk 2
7/2008, wk 2
7/2008, wk 2
7/2008, wk 2
7/2008, wk 2
7/2008, wk 2
7/2008, wk 2
period 6
9/2008, wk 2
9/2008, wk 2
9/2008, wk 2
9/2008, wk 2
9/2008, wk 2
9/2008, wk 2
9/2008, wk 2
9/2008, wk 2
1 Verify that site IDs match IDs in Section IV and on your distribution system schematic (See
Section VII of this form). Attach additional copies if you are required to select more than 8
standard monitoring locations.
2 period = monitoring period. Complete for the number of periods from Section II. C. Can list exact
date or week (e.g., week of 7/9/07)
IDSE Guidance Manual for the Final Stage 2 DBPR H-4
January 2006
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Form 6: Standard Monitoring Plan
PageS of 6
VI. PLANNED STAGE 1 DBPR COMPLIANCE MONITORING SCHEDULE*
Stage 1 DBPR
Monitoring Site
ID (from map) 1
Stage 1 #1
Stage 1 #2
Stage 1 #3
Stage 1 #4
Stage 1 #5
Stage 1 #6
Stage 1 #7
Stage 1 #8
Projected Sampling Date (date or week) 2
Period 1
10/2007, wk 2
10/2007, wk 2
10/2007, wk 2
10/2007, wk 2
10/2007, wk 2
10/2007, wk 2
10/2007, wk 2
10/2007, wk 2
Period 2
1/2008, wk 2
1/2008, wk 2
1/2008, wk 2
1/2008, wk 2
1/2008, wk 2
1/2008, wk 2
1/2008, wk 2
1/2008, wk 2
Period 3
4/2008, wk2
4/2008, wk2
4/2008, wk2
4/2008, wk2
4/2008, wk2
4/2008, wk2
4/2008, wk2
4/2008, wk2
Period 4
7/2008, wk 2
7/2008, wk 2
7/2008, wk 2
7/2008, wk 2
7/2008, wk 2
7/2008, wk 2
7/2008, wk 2
7/2008, wk 2
1 Verify that site IDs match IDs on your distribution system schematic (See Section VII of
this form). Attach additional copies if you are required to monitor at more than 8 Stage 1
DBPR sites.
2 period = monitoring period. Complete for the number of periods in which you must conduct
Stage 1 DBPR monitoring during IDSE monitoring. Can list exact date or week (e.g., week
of 7/9/07)
VII. DISTRIBUTION SYSTEM SCHEMATIC*
ATTACH a schematic of your distribution system.
Distribution system schematics are not confidential and should not contain information
that poses a security risk to your system. EPA recommends that you use one of two
options:
Option 1: Distribution system schematic with no landmarks or addresses
indicated. Show locations of sources, entry points, storage facilities, standard
monitoring locations, and Stage 1 compliance monitoring locations (required). Also
include pressure zone boundaries and locations of pump stations. Provide map
scale.
Option 2: City map without locations of pipes indicated. Show locations of
sources, entry points, storage facilities, standard monitoring locations, and Stage 1
compliance monitoring locations (required). Also include boundaries of the
distribution system, pressure zone boundaries and locations of pump stations.
Provide map scale.
IDSE Guidance Manual for the Final Stage 2 DBPR H-5
January 2006
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Form 6: Standard Monitoring Plan
VIM. ATTACHMENTS
is Distribution System Schematic* (Section VII).
is Additional sheets for the summary of data or site justifications (Sections III and IV).
is Additional copies of Page 3 for justification of Standard Monitoring Sites (Section
IV). Required if you are a subpart H system serving more than 49,999 people or
a ground water system serving more than 499,999 people.
D Additional sheets for explaining how you used data other than TTHM, HAAS, and
temperature data to select your peak historical month (Section V).
H Additional copies of Page 4 for proposed monitoring schedule (Section V).
Required if you are a subpart H system serving more than 49,999 people or a
ground water system serving more than 499,999 people.
D Additional sheets for planned Stage 1 DBPR compliance monitoring schedule
(Section VI).
Total Number of Pages in Your Plan 11
Note: Fields with an asterisk (*) are required by the Stage 2 DBPR
IDSE Guidance Manual for the Final Stage 2 DBPR H-6 January 2006
-------
Form 6: Standard Monitoring Plan Attachment #1
IV. JUSTIFICATION OF STANDARD MONITORING SITES*
Standard
Monitoring
Site ID
(from map)1
Standard
Monitoring #9
Standard
Monitoring
#10
Standard
Monitoring
#11
Standard
Monitoring
#12
Standard
Monitoring
#13
Standard
Monitoring
#14
Standard
Monitoring
#15
Standard
Monitoring
#16
Site Type
n Near Entry Pt
n Avg. Res. Time
D High TTHM
H High HAAS
n Near Entry Pt
n Avg. Res. Time
D High TTHM
H High HAAS
n Near Entry Pt
n Avg. Res. Time
H High TTHM
D High HAAS
n Near Entry Pt
n Avg. Res. Time
H High TTHM
D High HAAS
n Near Entry Pt
n Avg. Res. Time
H High TTHM
D High HAAS
n Near Entry Pt
n Avg. Res. Time
H High TTHM
D High HAAS
n Near Entry Pt
n Avg. Res. Time
H High TTHM
n High HAAS
n Near Entry Pt
n Avg. Res. Time
H High TTHM
n High HAAS
Justification
See attached sheets.
See attached sheets.
See attached sheets.
See attached sheets.
See attached sheets.
See attached sheets.
See attached sheets.
See attached sheets.
1 Site IDs should match IDs in Section IV and on your distribution system schematic (See
Section VII of this form). Attach additional copies of this sheet if you are required to select
more than 8 standard monitoring locations or need more room.
IDSE Guidance Manual for the Final Stage 2 DBPR H-7
January 2006
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Justification of Standard Monitoring Sites Attachment #2
Standard Monitoring #1
Entry point to the distribution system for the southern part of the system (Hardwood Water Treatment
Plant). This is where the first group of customers receives water.
Standard Monitoring #2
Entry point to the distribution system for the Softwood River Water Treatment Plant. This location is just
after the high service pumps at the Water Treatment Plant.
Standard Monitoring #3
Represents average residence time of water in the southern section of the system. In the summer
months, this TCR site typically has chlorine residuals that are close to our calculated system-wide average
for the area served by the Hardwood WTP (1.2 mg/L). There are no storage facilities between the
treatment plant and this location. The site is on an 8 inch water main.
Standard Monitoring #4
Represents average residence time of water in the southern part of the system. There are no storage
facilities between the treatment plant and this location. Although this site is physically close to standard
monitoring site #3, site #3 and site #4 are at the edges of different pressure zones. The chlorine residual
concentration at this location is typically 30 percent less than the system-wide average (0.8 mg/L) in the
summer months. However, we attribute this additional loss of chlorine to the fact that the transmission
and distribution lines serving this area are older unlined cast iron and have been observed to show
significant build-up of corrosion by-products. The site is on a 12 inch transmission main.
Standard Monitoring #5
Represents average residence time of water in northern part of the system. In the summer months, this
TCR site typically has chlorine residuals that are close to our calculated system-wide average for the area
served by the Softwood WTP (1.0 mg/L). There are no storage facilities between the treatment plant and
this location. The site is in a residential area with predominantly 8 and 10 inch water mains.
Standard Monitoring #6
Represents average residence time in the northern part of the system. Although chlorine residual in the
summer months is on the low end of the system-wide average (1.0 mg/L), we think this can be attributed
to some older cast iron water mains in the area. Even though it is close in proximity to standard
monitoring site #5, it is at the edge of a different pressure zone from Standard Monitoring Site #5. The site
is on a 12 inch main.
Standard Monitoring #7
Represents high HAAS levels. Sample location is in an area approaching the perimeter of the system in
the western pressure zone. Chlorine residual at this location ranges between 0.3 and 0.6 mg/L in the
summer months, and the HPCs are consistently below 100 cfu/mL year round. The site is on a 6 inch
main and is not downstream of any storage facilities.
Standard Monitoring #8
Represents high HAAS levels in the southern part of the system and is hydraulically downstream of the
Oakville Ground Storage Facility, which has a residence time of about 1 1/4 days in the summer months.
This is a TCR site with residual concentrations ranging from 0.4 to 0.7 mg/L in the summer months and
HPCs are usually less than 200 cfu/mL. The site is on an 8 inch water main.
Standard Monitoring #9
Represents high HAAS levels in the mixing zone. This site is sometimes served by water that is
hydraulically downstream of the Weeping Willow Tank. The chlorine residual varies. It is consistently less
than 1.0 mg/L but never below 0.4 mg/L and the HPCs are usually low (below 100 cfu/mL). The site is in a
commercial area served by 8 and 10 inch water mains.
IDSE Guidance Manual for the Final Stage 2 DBPR fTs January 2006
-------
Justification of Standard Monitoring Sites (Continued) Attachment #3
Standard Monitoring #10
Represents high HAAS levels in the northern part of the system. The site is not served by any storage
facilities, but the location is near the north-western perimeter of the system where we have not historically
monitored for TTHM or HAAS. It is in a business district served mainly by 8 inch water mains. The
chlorine residual levels at this location range from 0.5 to 0.8 mg/L in the summer, and HPC levels are
generally < 100 cfu/mL.
Standard Monitoring #11
Represents high TTHM levels. This site is in the central portion of the system and is served by the
Hardwood WTP. It is in a sparsely populated area with larger service lines (10 and 12 inches). Chlorine
residuals near this location are on the low side (0.3 - 0.5) in the summer. We are concerned that this area
has high water age because of the relatively large pipe size and low demand. We have not historically
monitored for TTHM or HAA5 in this area.
Standard Monitoring #12
Represents high TTHM levels. This site is at a location on the northern edge of the central pressure zone,
geographically distant from the Hardwood WTP. It is at the entrance to a small subdivision (approx 15
houses) in the Oakville community and is on a 6 inch water line. It is not served by any storage facilities,
but residuals in this area are very low in the summer months (< 0.2 mg/L). Also, our operations staff
noted that this is a historic problem area in terms of customer complaints of stale or discolored water and
chlorine residual maintenance.
Standard Monitoring #13
Represents high TTHM levels in the south-eastern portion of this system on a 4-inch water line. This
location has been problematic in the past due to positive total coliform test results, non-detectable chlorine
residuals, high heterotrophic plate count results, and odor complaints. A 4-inch blow-off was installed
downstream of this location, but it continues to have periodic poor water quality. Although close in
proximity, it is at the edge of a different pressure zone from our Stage 1 compliance monitoring site # 8.
Standard Monitoring #14
Represents high TTHM levels. This site is in the mixing zone and is influenced by both the Softwood and
Hardwood WTPs. During high demand periods, it receives water from the Appleville Storage Tank, which
has a residence time of 2 days in the summer. Chlorine residuals at this location are generally very low,
indicating this may be a hydraulic dead end.
Standard Monitoring #15
Represents high TTHM levels in the northwestern corner of the system. This location is downstream from
the Cypressville Storage Tank, which has a residence time of 1 to 2 days in the summer. The site is on a
6 inch water main leading into several sparsely populated residential areas. There are often low chlorine
residuals in the areas downstream of this tank.
Standard Monitoring #16
Represents high TTHM levels at the edge of the mixing zone. This sampling location is in the mixed zone
before the last group of connections near the end of the distribution system. It is on a 6 inch line and
receives water from the Cypressville Storage Tank. We have limited chlorine residual data for this area,
but operators suspect that it is low in the summer due to the high water age in this area.
IDSE Guidance Manual for the Final Stage 2 DBPR H-9 January 2006
-------
Form 6: Standard Monitoring Plan
Attachment #4
V. PEAK HISTORICAL MONTH AND PROPOSED STANDARD MONITORING DATES
A. Peak Historical Month*
B. If Multiple Sources, Source Used to Determine Peak Historical Month
(write "N/A" if only one source in your system)
C. Peak Historical Month Based On* (check all that apply)
D High TTHM n Warmest water temperature
D High HAAS
If you used other information to select your peak historical month, explain here
(attach additional sheets if needed)
D. Proposed Standard Monitoring Schedule*
Standard Monitoring
Site ID
(from map) 1
SM#9
SM#10
SM#11
SM#12
SM#13
SM#14
SM#15
SM#16
Projected Sampling Date (date or week)2
period 1
11/2007, wk 2
11/2007, wk 2
11/2007, wk 2
11/2007, wk 2
11/2007, wk 2
11/2007, wk 2
11/2007, wk 2
11/2007, wk 2
period 2
1/2008, wk 2
1/2008, wk 2
1/2008, wk 2
1/2008, wk 2
1/2008, wk 2
1/2008, wk 2
1/2008, wk 2
1/2008, wk 2
period 3
3/2008, wk 2
3/2008, wk 2
3/2008, wk 2
3/2008, wk 2
3/2008, wk 2
3/2008, wk 2
3/2008, wk 2
3/2008, wk 2
period 4
5/2008, wk 2
5/2008, wk 2
5/2008, wk 2
5/2008, wk 2
5/2008, wk 2
5/2008, wk 2
5/2008, wk 2
5/2008, wk 2
period 5
7/2008, wk 2
7/2008, wk 2
7/2008, wk 2
7/2008, wk 2
7/2008, wk 2
7/2008, wk 2
7/2008, wk 2
7/2008, wk 2
period 6
9/2008, wk 2
9/2008, wk 2
9/2008, wk 2
9/2008, wk 2
9/2008, wk 2
9/2008, wk 2
9/2008, wk 2
9/2008, wk 2
1 Verify that site IDs match IDs in Section IV and on your distribution system schematic (See
Section VII of this form). Attach additional copies if you are required to select more than 8
standard monitoring locations.
2 period = monitoring period. Complete for the number of periods from Section II. C. Can list exact
date or week (e.g., week of 7/9/07)
IDSE Guidance Manual for the Final Stage 2 DBPR H-10
January 2006
-------
Elm City Distribution System Schematic
Scale: 1:5000'
Attachment #5
O^fr*f—
MIXINGZONE
Softwood WTP
Fbplarville
{_) Stage 1 DBPRsite
O Standard Monitoring Site
-------
This page intentionally left blank.
IDSE Guidance Manual for the Final Stage 2 DBPR H-12 January 2006
-------
Form 7: IDSE Report for Standard Monitoring pagei of 9
I. GENERAL INFORMATION
A. PWS Information*
PWSID: US1111111
PWS Name: Elm City
PWS Address: 1234 Main Street
| B. Date Submitted* Dec 1. 2008
City: Elm City State: US Zip: 99999
Population Served 160,000
System Type: Source Water Type:
H CWS H Subpart H
D NTNCWS D Ground
C. PWS Operations
Residual Disinfectant Type: is Chlorine n Cf
Number of Disinfected Sources: 2 Surface
Buying / Selling Relationships:
D Consecutive System
D Wholesale System
H Neither
iloramines n Other:
GWUDI Ground Purchased
D. Contact Person*
Name: Mr. Ronald Doe, P.E.
Title: Water Superintendent
Phone #: 123-555-0000
E-mail: Rdoe@ci.elmcity.us
Fax#: 123-555-0001
II. STAGE 2 DBPR REQUIREMENTS*
A. Number of B. Schedule C
Compliance Monitoring
Sites
Highest TTHM: 3 H Schedule 1
Highest HAAS: 3 D Schedule 2
Existing Stage 1: 2 n Schedule 3
Total: 8 D Schedule 4
Compliance Monitoring Frequency
n During peak historical month
(1 monitoring period)
H Every 90 days (4 monitoring periods)
IDSE Guidance Manual for the Final Stage 2 DBPR H-13
January 2006
-------
Form 7: IDSE Report for Standard Monitoring Page20f9
I. MONITORING RESULTS*
A. Did you deviate in any way from your approved standard is Yes n No
monitoring plan?
If YES, explain (attach additional pages if necessary):
The IDSE Monitoring Plan indicated samples should be taken during the second
week of March, 2008. Our sampler was very ill this week and could not collect all of
the standard monitoring samples. He collected all remaining samples on Monday
and Tuesday of the next week.
B. Where were your TTHM and HAAS samples analyzed?
is In-House
Is your in-house laboratory certified? is Yes n No
D Certified Laboratory
Name of certified laboratory:
C. What method(s) was used to analyze your TTHM and HAAS
samples?
TTHM HAAS
D EPA 502.2 D EPA 552.1
D EPA 524.2 D EPA 552.2
B EPA 551.1 H EPA 552.3
D SM 6251 B
IDSE Guidance Manual for the Final Stage 2 DBPR H-14 January 2006
-------
Form 7: IDSE Report for Standard Monitoring pages of 9
III. MONITORING RESULTS (Continued)*
D. II
DSE Standard Monitoring Results - TTHM
Site ID1
Standard
Monitoring #1
Standard
Monitoring #2
Standard
Monitoring #3
Standard
Monitoring #4
Standard
Monitoring #5
Standard
Monitoring #6
Standard
Monitoring #7
Standard
Monitoring #8
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
TTHM (mg/L)
11/13/07
0.022
11/13/07
0.031
11/13/07
0.042
11/13/07
0.048
11/13/07
0.025
11/13/07
0.033
11/13/07
0.044
11/13/07
0.040
1/9/08
0.016
1/9/08
0.027
1/9/08
0.033
1/9/08
0.041
1/9/08
0.023
1/9/08
0.017
1/9/08
0.026
1/9/08
0.035
3/14/08
0.028
3/14/08
0.035
3/14/08
0.039
3/14/08
0.047
3/14/08
0.042
3/14/08
0.041
3/17/08
0.056
3/17/08
0.050
5/13/08
0.036
5/13/08
0.031
5/13/08
0.040
5/13/08
0.055
5/13/08
0.048
5/13/08
0.050
5/13/08
0.052
5/13/08
0.064
7/10/08
0.037
7/10/08
0.039
7/10/08
0.048
7/10/08
0.056
7/10/08
0.049
7/10/08
0.058
7/10/08
0.070
7/10/08
0.064
9/9/08
0.030
9/9/08
0.030
9/9/08
0.045
9/9/08
0.043
9/9/08
0.035
9/9/08
0.045
9/9/08
0.042
9/9/08
0.052
LRAA
0.028
0.032
0.041
0.048
0.037
0.041
0.048
0.051
1 Verify that site IDs for IDSE standard monitoring sites match the site IDs in your Standard Monitoring Plan.
Attach additional sheets as needed for IDSE standard monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
H-15
January 2006
-------
Form 7: IDSE Report for Standard Monitoring page4of9
III. MONITORING RESULTS (Continued)*
E. 1
DSE Standard Monitoring Results - HAAS
Site ID1
Standard
Monitoring #1
Standard
Monitoring #2
Standard
Monitoring #3
Standard
Monitoring #4
Standard
Monitoring #5
Standard
Monitoring #6
Standard
Monitoring #7
Standard
Monitoring #8
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
HAAS (mg/L)
11/13/07
0.030
11/13/07
0.025
11/13/07
0.041
11/13/07
0.027
11/13/07
0.040
11/13/07
0.029
11/13/07
0.062
11/13/07
0.049
1/9/08
0.028
1/9/08
0.026
1/9/08
0.030
1/9/08
0.019
1/9/08
0.028
1/9/08
0.019
1/9/08
0.035
1/9/08
0.047
3/14/08
0.032
3/14/08
0.022
3/14/08
0.022
3/14/08
0.020
3/14/08
0.023
3/14/08
0.014
3/17/08
0.055
3/17/08
0.050
5/13/08
0.027
5/13/08
0.034
5/13/08
0.029
5/13/08
0.025
5/13/08
0.056
5/13/08
0.020
5/13/08
0.052
5/13/08
0.059
7/10/08
0.033
7/10/08
0.030
7/10/08
0.036
7/10/08
0.025
7/10/08
0.040
7/10/08
0.021
7/10/08
0.052
7/10/08
0.058
9/9/08
0.026
9/9/08
0.021
9/9/08
0.040
9/9/08
0.029
9/9/08
0.052
9/9/08
0.023
9/9/08
0.063
9/9/08
0.050
LRAA
0.029
0.026
0.033
0.024
0.040
0.021
0.053
0.052
1 Verify that site IDs for IDSE standard monitoring sites match the site IDs in your Standard Monitoring Plan.
Attach additional sheets as needed for IDSE standard monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
H-16
January 2006
-------
Form 7: IDSE Report for Standard Monitoring pages of 9
III. MONITORING RESULTS (Continued)*
F. Sis
ige 1 DBPR Compliance Monitoring Results - TTHM
Site ID1
Stage 1 #1
(avg. res. time)
Stage 1 #2
(avg. res. time)
Stage 1 #3
(avg. res. time)
Stage 1 #4
(max. res. time)
Stage 1 #5
(avg. res. time)
Stage 1 #6
(avg. res. time)
Stage 1 #7
(avg. res. time)
Stage 1 #8
(max. res. time)
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
TTHM (mg/L)
10/10/07
0.062
10/10/07
0.045
10/10/07
0.048
10/10/07
0.056
10/10/07
0.042
10/10/07
0.039
10/10/07
0.050
10/10/07
0.060
1/7/08
0.045
1/7/08
0.036
1/7/08
0.032
1/7/08
0.042
1/7/08
0.044
1/7/08
0.046
1/7/08
0.041
1/7/08
0.065
4/7/08
0.034
4/7/08
0.042
4/7/08
0.034
4/7/08
0.057
4/7/08
0.020
4/7/08
0.049
4/7/08
0.022
4/7/08
0.050
7/8/08
0.056
7/8/08
0.045
7/8/08
0.067
7/8/08
0.076
7/8/08
0.062
7/8/08
0.050
7/8/08
0.059
7/8/08
0.073
LRAA
0.049
0.042
0.045
0.058
0.042
0.046
0.043
0.062
1 Verify that site IDs for Stage 1 compliance monitoring sites match the site IDs in your Standard Monitoring Plan.
Attach additional sheets as needed for Stage 1 compliance monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
H-17
January 2006
-------
Form 7: IDSE Report for Standard Monitoring page6of9
III. MONITORING RESULTS (Continued)*
G. S
tage 1 DBPR Compliance Monitoring Results - HAAS
Site ID1
Stage 1 #1
(avg. res. time)
Stage 1 #2
(avg. res. time)
Stage 1 #3
(avg. res. time)
Stage 1 #4
(max. res. time)
Stage 1 #5
(avg. res. time)
Stage 1 #6
(avg. res. time)
Stage 1 #7
(avg. res. time)
Stage 1 #8
(max. res. time)
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
HAAS (mg/L)
10/10/07
0.045
10/10/07
0.056
10/10/07
0.049
10/10/07
0.028
10/10/07
0.041
10/10/07
0.041
10/10/07
0.058
10/10/07
0.030
1/7/08
0.024
1/7/08
0.047
1/7/08
0.032
1/7/08
0.021
1/7/08
0.034
1/7/08
0.022
1/7/08
0.048
1/7/08
0.019
4/7/08
0.032
4/7/08
0.050
4/7/08
0.062
4/7/08
0.025
4/7/08
0.045
4/7/08
0.030
4/7/08
0.046
4/7/08
0.022
7/8/08
0.043
7/8/08
0.055
7/8/08
0.045
7/8/08
0.026
7/8/08
0.033
7/8/08
0.039
7/8/08
0.064
7/8/08
0.037
LRAA
0.036
0.052
0.047
0.025
0.038
0.033
0.054
0.027
1 Verify that site IDs for Stage 1 compliance monitoring sites match the site IDs in your Standard Monitoring Plan.
Attach additional sheets as needed for Stage 1 compliance monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
H-18
January 2006
-------
Form 7: IDSE Report for Standard Monitoring page? of 9
IV. JUSTIFICATION OF STAGE 2 DBPR COMPLIANCE MONITORING SITES*
Stage 2
Compliance
Monitoring
Site ID
Standard
Monitoring
#13
Standard
Monitoring
#10
Stage 1 #7
Stage 1 #8
Standard
Monitoring
#14
Standard
Monitoring # 7
Stage 1 #1
Stage 1 # 2
Site Type
B Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
B Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
B Stage 1 DBPR
B Highest TTHM
D Highest HAAS
D Stage 1 DBPR
B Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
B Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
B Stage 1 DBPR
D Highest TTHM
B Highest HAAS
D Stage 1 DBPR
Justification
This site had the highest TTHM LRAA among all the
sites.
This site had the highest HAAS LRAA (and was not
selected as the highest TTHM site)
Among the Stage 1 DBPR compliance monitoring
locations with average water residence time, this site
had the highest HAAS LRAA
This site had the second highest TTHM LRAA
This site had the third highest TTHM LRAA
This site had the second highest HAAS LRAA
Among the Stage 1 DBPR compliance monitoring
locations with average water residence time, this site
had the highest TTHM LRAA. Stage 1 DBPR site #4
had higher TTHM LRAAs but is maximum residence
time site, therefore, it was not chosen.
This site had the third highest HAAS LRAA. Standard
Monitoring Site #8 had the same LRAA, but we chose
to use Stage 1 site #2 to maintain a historical record.
Attach additional copies of this sheet if you need more room.
IDSE Guidance Manual for the Final Stage 2 DBPR H-19
January 2006
-------
Form 7: IDSE Report for Standard Monitoring pages of 9
V. PEAK HISTORICAL MONTH AND PROPOSED STAGE 2 DBPR COMPLIANCE
MONITORING SCHEDULE
A.
B.
C.
Peak Historical Month* Julv
Is Your Peak Historical Month the Same as in Your IDSE Standard
Monitoring Plan?
H Yes D No
If no, explain how you selected your new peak historical month (attach
additional sheets if needed)
Proposed Stage 2 DBPR Compliance Monitoring Schedule*
Stage 2
Compliance
Monitoring
Site ID
SM#13
SM#10
Stage 1 # 7
Stage 1 # 8
SM#14
SM#7
Stage 1 # 1
Stage 1 # 2
Projected Sampling
period 1
4/2012wk2
4/2012wk2
4/2012wk2
4/2012wk2
4/2012wk2
4/2012wk2
4/2012wk2
4/2012wk2
period 2
7/2012wk2
7/2012wk2
7/2012wk2
7/2012wk2
7/2012wk2
7/2012wk2
7/2012wk2
7/2012wk2
Date (date or week)7
period 3
10/2012wk2
10/2012wk2
10/2012wk2
10/2012wk2
10/2012wk2
10/2012wk2
10/2012wk2
10/2012wk2
period 4
1/201 3 wk 2
1/201 3 wk 2
1/201 3 wk 2
1/201 3 wk 2
1/201 3 wk 2
1/2013wk2
1/201 3 wk 2
1/201 3 wk 2
1 period = monitoring period. Complete for the number of monitoring periods from Section
II. C.
Attach additional copies of this sheet if you need more room.
IDSE Guidance Manual for the Final Stage 2 DBPR H-20
January 2006
-------
Form 7: IDSE Report for Standard Monitoring Page90f9
VI. DISTRIBUTION SYSTEM SCHEMATIC*
ATTACH a schematic of your distribution system if it has changed since you submitted
your Standard Monitoring Plan (Form 6).
VII. ATTACHMENTS
D Additional sheets for explaining how and why you deviated from your standard
monitoring plan (Section III).
is Additional sheets for Standard Monitoring Results (Section III). REQUIRED if you are
a subpart H system serving more than 49,999 people or a ground water system
serving more than 499,999 people.
D Additional sheets for Stage 2 DBPR Compliance Monitoring Sites (Section IV).
REQUIRED if you are a subpart H system serving more than 249,999 people.
D Additional sheets for explaining how you selected the peak historical month (Section
V).
D Additional sheets for proposed Stage 2 DBPR peak historical month and compliance
monitoring schedule (Section V). REQUIRED if you are a subpart H system serving
more than 249,999 people.
D Distribution system schematic* (Section VI). REQUIRED if it has changed from
your approved IDSE standard monitoring plan.
D Compliance calculation procedures (for Stage 2 Compliance Monitoring Plan).
Total Number of Pages in Your Report: _11
Note: Fields with an asterisk (*) are required by the Stage 2 DBPR
IDSE Guidance Manual for the Final Stage 2 DBPR H-21 January 2006
-------
Form 7: IDSE Report for Standard Monitoring Attachment^
III. MONITORING RESULTS (Continued)*
D. 1C
)SE Standard Monitoring Results - TTHM
Site ID1
Standard
Monitoring #9
Standard
Monitoring #10
Standard
Monitoring #1 1
Standard
Monitoring #12
Standard
Monitoring #13
Standard
Monitoring #14
Standard
Monitoring #15
Standard
Monitoring #16
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
TTHM (mg/L)
11/14/07
0.047
11/14/07
0.022
11/14/07
0.045
11/14/07
0.061
11/14/07
0.072
11/14/07
0.055
11/14/07
0.052
11/14/07
0.055
1/10/08
0.033
1/10/08
0.020
1/10/08
0.025
1/10/08
0.042
1/10/08
0.032
1/10/08
0.033
1/10/08
0.036
1/10/08
0.031
3/17/08
0.049
3/17/08
0.051
3/18/08
0.062
3/18/08
0.056
3/18/08
0.065
3/18/08
0.068
3/18/08
0.048
3/18/08
0.072
5/14/08
0.052
5/14/08
0.050
5/14/08
0.060
5/14/08
0.050
5/14/08
0.070
5/14/08
0.062
5/14/08
0.056
5/14/08
0.049
7/9/08
0.062
7/9/08
0.052
7/9/08
0.060
7/9/08
0.068
7/9/08
0.085
7/9/08
0.080
7/9/08
0.070
7/9/08
0.068
9/10/08
0.037
9/10/08
0.042
9/10/08
0.064
9/10/08
0.051
9/10/08
0.071
9/10/08
0.062
9/10/08
0.065
9/10/08
0.069
LRAA
0.047
0.040
0.053
0.055
0.066
0.060
0.055
0.057
1 Verify that site IDs for IDSE standard monitoring sites match the site IDs in your Standard Monitoring Plan.
Attach additional sheets as needed for IDSE standard monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
H-22
January 2006
-------
Form 7: IDSE Report for Standard Monitoring Attachment#2
III. MONITORING RESULTS (Continued)*
E. 1C
)SE Standard Monitoring Results - HAAS
Site ID1
Standard
Monitoring #9
Standard
Monitoring #10
Standard
Monitoring #1 1
Standard
Monitoring #12
Standard
Monitoring #13
Standard
Monitoring #14
Standard
Monitoring #15
Standard
Monitoring #16
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
HAAS (mg/L)
11/14/07
0.040
11/14/07
0.067
11/14/07
0.033
11/14/07
0.028
11/14/07
0.039
11/14/07
0.034
11/14/07
0.034
11/14/07
0.034
1/10/08
0.034
1/10/08
0.058
1/10/08
0.030
1/10/08
0.028
1/10/08
0.033
1/10/08
0.031
1/10/08
0.028
1/10/08
0.025
3/17/08
0.045
3/17/08
0.056
3/18/08
0.042
3/18/08
0.039
3/18/08
0.041
3/18/08
0.042
3/18/08
0.028
3/18/08
0.046
5/14/08
0.058
5/14/08
0.044
5/14/08
0.040
5/14/08
0.045
5/14/08
0.039
5/14/08
0.030
5/14/08
0.040
5/14/08
0.048
7/9/08
0.065
7/9/08
0.065
7/9/08
0.046
7/9/08
0.040
7/9/08
0.062
7/9/08
0.058
7/9/08
0.054
7/9/08
0.038
9/10/08
0.048
9/10/08
0.050
9/10/08
0.038
9/10/08
0.033
9/10/08
0.045
9/10/08
0.038
9/10/08
0.038
9/10/08
0.028
LRAA
0.048
0.057
0.038
0.036
0.043
0.039
0.037
0.037
1 Verify that site IDs for IDSE standard monitoring sites match the site IDs in your Standard Monitoring Plan.
Attach additional sheets as needed for IDSE standard monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
H-23
January 2006
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IDSE Guidance Manual for the Final Stage 2 DBPR H-24 January 2006
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Appendix I
Example IDSE Standard Monitoring Plan and Report for
a Ground Water System Serving 200,000 People
This appendix is provided as an example IDSE standard monitoring plan and report for a
ground water system serving 200,000 people and choosing to complete standard monitoring.
For this example, the state did not require any modifications to the study plan.
Chapter 7 discusses the standard monitoring plan, conducting standard monitoring,
selection of Stage 2 DBPR sites, and preparing the standard monitoring report. The application
of the basic guidance on standard monitoring location selection and Stage 2 DBPR compliance
monitoring location selection is shown in this example, along with several instances of the use of
best professional judgement being applied.
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Form 6: Standard Monitoring Plan pageiofe
I. GENERAL INFORMATION
A. PWS Information*
PWSID: US5555555
PWS Name: Oak City
PWS Address: 124 Oak Drive
| B. Date Submitted* Sept 25. 2006
City: Oak City State: US Zip: 11111-1234
Population Served: 200,000
System Type: Source Water Type:
H CWS D Subpart H
D NTNCWS B Ground
C. PWS Operations
Residual Disinfectant Type: H Chlorine n Cl
Number of Disinfected Sources: Surface
D. Contact Person*
Name: Mr. Joseph Smith, P.E.
Title: Superintendent of Water
Phone #: 123-555-1111
E-mail: JSmith@ci.oakcity.us
II. IDSE REQUIREMENTS*
A. Number of Sites B. Schedule C
Total: 8
Near Entry Point: 1 H Schedule 1
Avg Residence Time: 1 n Schedule 2
High TTHM: 3 D Schedule 3
High HAAS: 3 D Schedule 4
Buying / Selling Relationships:
n Consecutive System
n Wholesale System
H Neither
iloramines n Other:
GWUDI 2 Ground Purchased
Fax#: 123-555-2222
. Standard Monitoring Frequency
n During peak historical month
(1 monitoring period)
H Every 90 days (4 monitoring periods)
n Every 60 days (6 monitoring periods)
IDSE Guidance Manual for the Final Stage 2 DBPR 1-1
January 2006
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Form 6: Standard Monitoring Plan page2of6
III. SELECTING STANDARD MONITORING SITES
A. I
eac
B.
mo
Data Evaluated Put a "/" in each box corresponding to the data that you used to select
h type of standard monitoring site. Check all that apply.
Data Type
Type of Site
Near
Entry Pt.
Avg. Residence
Time
High
TTHM
High
HAAS
System Configuration
Pipe layout, locations of storage facilities
Locations of sources and consecutive
system entry points
Pressure zones
Information on population density
Locations of large customers
/
/
/
/
/
/
Water Quality and Operational Data
Disinfectant residual data
Stage 1 DBP data
Other DBP data
Microbiological monitoring data (e.g., HPC)
Tank level data, pump run times
Customer billing records
/
/
/
/
/
/
/
/
Advanced Tools
Water distribution system model
Tracer study
Summary of Data* Provide a summary of data you relied on to justify standard
nitoring site selection, (attach additional sheets if needed)
The Blue Springs Well field is only in operation during high demand in the summer months, so we
focused most sites in the influence zone of the Silver Springs Well field which operates year round.
We used residual and HPC data from Total Coliform sites collected in 2005 and 2006 along with
Stage 1 DBPR data and our system map to select sites. We evaluated chlorine residual data from
June, July, and August which ranged from 2.0 mg/L at the Silver Springs disinfection station to no
detect in the distribution system. The system average during the summer is typically around 1.1 mg/L.
Sites with residuals close to this were considered for average residence time sites. Residuals along
with data on storage tanks, booster stations, and operator notes were used to locate areas of high
residence time for high TTHM and HAAS sites. Areas of biological activity were identified using
disinfectant residual data because we do not have a lot of HPC data. Sites were plotted on our system
map to ensure adequate coverage of the different geographic and operational areas.
IDSE Guidance Manual for the Final Stage 2 DBPR 1-2
January 2006
-------
Form 6: Standard Monitoring Plan pages ore
IV. JUSTIFICATION OF STANDARD MONITORING SITES*
Standard
Monitoring
Site ID
(from map)1
Standard
Monitoring #1
Standard
Monitoring #2
Standard
Monitoring #3
Standard
Monitoring #4
Standard
Monitoring #5
Standard
Monitoring #6
Standard
Monitoring #7
Standard
Monitoring #8
Site Type
H Near Entry Pt
n Avg. Res. Time
D High TTHM
D High HAAS
n Near Entry Pt
H Avg. Res. Time
D High TTHM
D High HAAS
n Near Entry Pt
n Avg. Res. Time
H High TTHM
D High HAAS
n Near Entry Pt
n Avg. Res. Time
H High TTHM
D High HAAS
n Near Entry Pt
n Avg. Res. Time
H High TTHM
D High HAAS
n Near Entry Pt
n Avg. Res. Time
D High TTHM
H High HAAS
n Near Entry Pt
n Avg. Res. Time
D High TTHM
H High HAAS
n Near Entry Pt
n Avg. Res. Time
D High TTHM
H High HAAS
Justification
See attached sheets.
See attached sheets.
See attached sheets.
See attached sheets.
See attached sheets.
See attached sheets.
See attached sheets.
See attached sheets.
1 Verify that site IDs match IDs in Section IV and on your distribution system schematic (See
Section VII of this form). Attach additional copies if you are required to select more than 8
standard monitoring locations or need more room.
IDSE Guidance Manual for the Final Stage 2 DBPR 1-3
January 2006
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Form 6: Standard Monitoring Plan
Page 4 of 6
V. PEAK HISTORICAL MONTH AND PROPOSED STANDARD MONITORING SCHEDULE
A. Peak Historical Month* August
B. If Multiple Sources, Source Used to Determine Peak Historical Month
(write "N/A" if only one source in your system)
Silver Springs Well field
C. Peak Historical Month Based On* (check all that apply)
is High TTHM is Warmest water temperature
B High HAAS
If you used other information to select your peak historical month, explain here
(attach additional sheets if needed)
D. Proposed Standard Monitoring Schedule*
Standard
Monitoring Site
ID
(from map) 1
SM#1
SM#2
SM#3
SM#4
SM#5
SM#6
SM#7
SM#8
Projected Sampling Date (date or week)2
period 1
2nd week 11/2007
2nd week 11/2007
2nd week 11/2007
2nd week 11/2007
2nd week 11/2007
2nd week 11/2007
2nd week 11/2007
2nd week 11/2007
period 2
2nd week 2/2008
2nd week 2/2008
2nd week 2/2008
2nd week 2/2008
2nd week 2/2008
2nd week 2/2008
2nd week 2/2008
2nd week 2/2008
period 3
2nd week 5/2008
2nd week 5/2008
2nd week 5/2008
2nd week 5/2008
2nd week 5/2008
2nd week 5/2008
2nd week 5/2008
2nd week 5/2008
period 4
2nd week 8/2008
2nd week 8/2008
2nd week 8/2008
2nd week 8/2008
2nd week 8/2008
2nd week 8/2008
2nd week 8/2008
2nd week 8/2008
period 5
period 6
1 Verify that site IDs match IDs in Section IV and on your distribution system schematic
(See Section VII of this form). Attach additional copies if you are required to select more
than 8 standard monitoring locations.
2 period = monitoring period. Complete for the number of periods from Section II. C. Can
list exact date or week (e.g., week of 7/9/07)
IDSE Guidance Manual for the Final Stage 2 DBPR 1-4
January 2006
-------
Form 6: Standard Monitoring Plan
PageS of 6
VI. PLANNED STAGE 1 DBPR COMPLIANCE MONITORING SCHEDULE*
Stage 1 DBPR
Monitoring Site
ID (from map) 1
Stage 1 #1
max. residence
time site
Stage 1 #2
max. residence
time site
Projected Sampling Date (date or week) 2
Period 1
2nd week of
11/2007
2nd week of
11/2007
Period 2
2nd week of
2/2008
2nd week of
2/2008
Period 3
2nd week of
5/2008
2nd week of
5/2008
Period 4
2nd week of
8/2008
2nd week of
8/2008
1 Verify that site IDs match IDs on your distribution system schematic (See Section VII of
this form). Attach additional copies if you are required to monitor at more than 8 Stage 1
DBPR sites.
2 period = monitoring period. Complete for the number of periods in which you must conduct
Stage 1 DBPR monitoring during IDSE monitoring. Can list exact date or week (e.g., week
of 7/9/07)
VII. DISTRIBUTION SYSTEM SCHEMATIC*
ATTACH a schematic of your distribution system.
Distribution system schematics are not confidential and should not contain information
that poses a security risk to your system. EPA recommends that you use one of two
options:
Option 1: Distribution system schematic with no landmarks or addresses
indicated. Show locations of sources, entry points, storage facilities, standard
monitoring locations, and Stage 1 compliance monitoring locations (required). Also
include pressure zone boundaries and locations of pump stations. Provide map
scale.
Option 2: City map without locations of pipes indicated. Show locations of
sources, entry points, storage facilities, standard monitoring locations, and Stage 1
compliance monitoring locations (required). Also include boundaries of the
distribution system, pressure zone boundaries and locations of pump stations.
Provide map scale.
IDSE Guidance Manual for the Final Stage 2 DBPR 1-5
January 2006
-------
Form 6: Standard Monitoring Plan
VIM. ATTACHMENTS
is Distribution System Schematic* (Section VII).
is Additional sheets for the summary of data or site justifications (Sections III and IV).
D Additional copies of Page 3 for justification of Standard Monitoring Sites (Section
IV). Required if you are a subpart H system serving more than 49,999 people or
a ground water system serving more than 499,999 people.
D Additional sheets for explaining how you used data other than TTHM, HAAS, and
temperature data to select your peak historical month (Section V).
D Additional copies of Page 4 for proposed monitoring schedule (Section V).
Required if you are a subpart H system serving more than 49,999 people or a
ground water system serving more than 499,999 people.
D Additional sheets for planned Stage 1 DBPR compliance monitoring schedule
(Section VI).
Total Number of Pages in Your Plan 10_
Note: Fields with an asterisk (*) are required by the Stage 2 DBPR
IDSE Guidance Manual for the Final Stage 2 DBPR 1-6 January 2006
-------
Oak City Distribution System Schematic
Attachment #1
Scale =1:6,000'
Blue Disinfection
Station (Seasonal
Source)
Silver Springs
^Wellfield
0 ^
Elevated Storage
Tank
Ground StorageTank
Pump Station
Chlorine Booster Station
Stage 1 DBPR site
Standard Monitoring site
^^^_/ Silv
I Disinfl
Silver Springs
Disinfection Station
IDSE Guidance Manual for the Final Stage 2 DBPR I- 7
January 2006
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IDSE Guidance Manual for the Final Stage 2 DBPR 1-8 January 2006
-------
Justification of IDSE Monitoring Sites Attachment #2
Standard Monitoring #1
Chosen to represent the entry point to the distribution system from the Silver Spring disinfection
station. The Silver Spring disinfection station has a much higher annual flow than the Blue
disinfection station, which uses a seasonal source. The site is located on a 16 inch water main.
Standard Monitoring #2
Chosen to represent average residence time in the system. Chlorine residual concentrations in
the surrounding area are close to system average (1.1 mg/L). There are no storage facilities or
booster stations between the entry point and this site located at the edge of the mixing zone in the
Silver Spring disinfection station Service area. The site is located in a residential zone on a 6
inch main.
Standard Monitoring #3
Chosen to represent high TTHM levels in the Silver Spring disinfection station influence zone
and the mixing zone. This monitoring location is located before the last group of connections on
a 6 inch pipe in proximity to the end of the distribution system in the mixing zone. It is also
downstream of a booster station. At this location, water demand tends to be low, total chlorine
levels are always low (ranging between 0.3 and 0.9 mg/L) and HPCs are often greater than 200
cfu/mL. Operations staff indicate this site has a lot of customers complaints.
Standard Monitoring #4
Chosen to represent high TTHM levels in the Silver Spring disinfection station influence zone.
This monitoring location is located near the TCR #4 sample site, and before the last group of
connections before the end of the distribution system. This site is in a 12 inch main in the
extremities of the system and is likely to have high water age during periods of low demand.
Standard Monitoring #5
Chosen to represent high TTHM levels in both influence zones. This monitoring location is after
the first group of connections (approximately 0.5 miles) downstream of a 1.5 MG elevated
storage facility in the influence zone of the Blue disinfection station. Operations data indicate
this reservoir may have high water age during the summer months. DBF data at the nearby
Stage 1 DBPR sampling site indicate high TTHM and HAAS levels for this area.
Standard Monitoring #6
Chosen to represent high HAAS levels in the Silver Spring disinfection station influence zone.
Sample tap is a hose bib at an elementary school located in a zone of the distribution system with
water age greater than average near a storage tank. Total chlorine levels at this location range
between 0.9 and 1.2 mg/L. The site is located on an 8 inch main.
IDSE Guidance Manual for the Final Stage 2 DBPR 1-9 January 2006
-------
Justification of IDSE Monitoring Sites (Continued) Attachment #2
Standard Monitoring #7
Chosen to represent high HAAS levels in the Silver Spring disinfection station influence zone
and the mixing zone. This location is a dedicated sampling location on an 8 inch main routinely
used for monitoring water quality in downtown Oak City. It is located near an elevated storage
tank. In this area, the water age is greater than the average, but the total chlorine is never below
0.7 mg/L.
Standard Monitoring #8
Chosen to represent high HAAS levels in the Blue disinfection station influence zone. Total
chlorine levels at this location range between 0.8 and 1.4 mg/L. The site is on the extremities of
the system, in an area where DBF monitoring has not traditionally been performed. It is on a 6
inch main.
IDSE Guidance Manual for the Final Stage 2 DBPR I-10 January 2006
-------
Form 7: IDSE Report for Standard Monitoring pagei Of9
I. GENERAL INFORMATION
A. PWS Information*
PWSID: US5555555
PWS Name: Oak City
PWS Address: 124 Oak Drive
| B. Date Submitted* Nov 30. 2008
City: Oak City State: US Zip: 11111-1234
Population Served: 200,000
System Type: Source Water Type:
H CWS D Subpart H
D NTNCWS B Ground
C. PWS Operations
Residual Disinfectant Type: is Chlorine n Cf
Number of Disinfected Sources: Surface
Buying / Selling Relationships:
n Consecutive System
n Wholesale System
H Neither
iloramines n Other:
GWUDI 2 Ground Purchased
D. Contact Person*
Name: Mr. Joseph Smith, P.E.
Title: Superintendent of Water
Phone #: 123-555-1111
E-mail: JSmith@ci.oakcity.us
Fax#: 123-555-2222
II. STAGE 2 DBPR REQUIREMENTS*
A. Number of B. Schedule C
Compliance Monitoring
Sites
Highest TTHM: 3 H Schedule 1
Highest HAAS: 2 D Schedule 2
Existing Stage 1:1 n Schedule 3
Total: 6 D Schedule 4
Compliance Monitoring Frequency
n During peak historical month
(1 monitoring period)
H Every 90 days (4 monitoring periods)
IDSE Guidance Manual for the Final Stage 2 DBPR I-11
January 2006
-------
Form 7: IDSE Report for Standard Monitoring
Page 2 of 9
I. MONITORING RESULTS*
A. Did you deviate in any way from your approved standard is Yes n No
monitoring plan?
If YES, explain (attach additional pages if necessary):
Sampling was planned for August 13, 2007 but system maintenance was planned in
the area of Standard monitoring location #1 for that day. The maintenance required
extensive system flushing so the samples were taken on the previous Friday.
B. Where were your TTHM and HAAS samples analyzed?
n In-House
Is your in-house laboratory certified? D Yes n No
H Certified Laboratory
Name of certified laboratory: Oak City Laboratories
C. What method(s) was used to analyze your TTHM and HAAS
samples?
TTHM HAAS
D EPA 502.2 D EPA 552.1
B EPA 524.2 D EPA 552.2
D EPA 551.1 D EPA 552.3
B SM 6251 B
IDSE Guidance Manual for the Final Stage 2 DBPR 1-12 January 2006
-------
Form 7: IDSE Report for Standard Monitoring page3of9
III. MONITORING RESULTS (Continued)*
D. 1C
)SE Standard Monitoring Results - TTHM
Site ID1
Standard Monitoring #1
Standard Monitoring #2
Standard Monitoring #3
Standard Monitoring #4
Standard Monitoring #5
Standard Monitoring #6
Standard Monitoring #7
Standard Monitoring #8
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
TTHM (mg/L)
11/19/07
0.026
11/19/07
0.054
11/19/07
0.062
11/19/07
0.049
11/19/07
0.038
11/19/07
0.033
11/19/07
0.035
11/19/07
0.031
2/18/08
0.022
2/18/08
0.039
2/18/08
0.061
2/18/08
0.058
2/18/08
0.068
2/18/08
0.029
2/18/08
0.029
2/18/08
0.033
5/19/08
0.030
5/19/08
0.042
5/19/08
0.072
5/19/08
0.072
5/19/08
0.075
5/19/08
0.041
5/19/08
0.037
5/19/08
0.038
8/17/08
0.035
8/17/08
0.056
8/17/08
0.075
8/17/08
0.069
8/17/08
0.071
8/17/08
0.042
8/17/08
0.047
8/17/08
0.041
LRAA
0.028
0.048
0.068
0.062
0.063
0.036
0.037
0.036
1 Verify that site IDs for IDSE standard monitoring sites match the site IDs in your Standard Monitoring Plan.
Attach additional sheets as needed for IDSE standard monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
1-13
January 2006
-------
Form 7: IDSE Report for Standard Monitoring page4of9
III. MONITORING RESULTS (Continued)*
E. 1C
)SE Standard Monitoring Results - HAAS
Site ID1
Standard Monitoring #1
Standard Monitoring #2
Standard Monitoring #3
Standard Monitoring #4
Standard Monitoring #5
Standard Monitoring #6
Standard Monitoring #7
Standard Monitoring #8
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
HAAS (mg/L)
11/19/07
0.020
11/19/07
0.022
11/19/07
0.021
11/19/07
0.020
11/19/07
0.024
11/19/07
0.043
11/19/07
0.036
11/19/07
0.033
2/18/08
0.024
2/18/08
0.029
2/18/08
0.025
2/18/08
0.021
2/18/08
0.028
2/18/08
0.038
2/18/08
0.040
2/18/08
0.042
5/19/08
0.033
5/19/08
0.036
5/19/08
0.026
5/19/08
0.038
5/19/08
0.042
5/19/08
0.048
5/19/08
0.046
5/19/08
0.043
8/17/08
0.037
8/17/08
0.040
8/17/08
0.028
8/17/08
0.028
8/17/08
0.045
8/17/08
0.052
8/17/08
0.040
8/17/08
0.040
LRAA
0.028
0.032
0.025
0.027
0.035
0.045
0.041
0.040
1 Verify that site IDs for IDSE standard monitoring sites match the site IDs in your Standard Monitoring Plan.
Attach additional sheets as needed for IDSE standard monitoring results.
IDSE Guidance Manual for the Final Stage 2 DBPR
1-14
January 2006
-------
Form 7: IDSE Report for Standard Monitoring page5of9
III. MONITORING RESULTS (Continued)*
F
. Stage 1 DBPR Compliance Monitoring Results - TTHM
Site ID1
Stage 1 #1
max. residence time site
Stage 1 #2
max. residence time site
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
TTHM (mg/L)
11/19/07
0.055
11/19/07
0.060
2/18/08
0.044
2/18/08
0.068
5/19/08
0.066
5/19/08
0.068
8/17/08
0.072
8/17/08
0.098
LRAA
0.059
0.074
1 Verify that site IDs for Stage 1 compliance monitoring sites match the site IDs in your Standard Monitoring Plan.
Attach additional sheets as needed for Stage 1 compliance monitoring results.
IDSE Guidance Manual for the final Stage 2 DBPR
1-15
January 2006
-------
Form 7: IDSE Report for Standard Monitoring page6of9
III. MONITORING RESULTS (Continued)*
G.
Stage 1 DBPR Compliance Monitoring Results - HAAS
Site ID1
Stage 1 #1
max. residence time site
Stage 1 #2
max. residence time site
Data Type
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
Sample Date
Sample Result
HAAS (mg/L)
11/19/07
0.024
11/19/07
0.042
2/18/08
0.032
2/18/08
0.033
5/19/08
0.043
5/19/08
0.030
8/17/08
0.045
8/17/08
0.038
LRAA
0.036
0.036
1 Verify that site IDs for Stage 1 compliance monitoring sites match the site IDs in your Standard Monitoring Plan.
Attach additional sheets as needed for Stage 1 compliance monitoring results.
IDSE Guidance Manual for the final Stage 2 DBPR
1-16
January 2006
-------
Form 7: IDSE Report for Standard Monitoring page7of9
IV. JUSTIFICATION OF STAGE 2 DBPR COMPLIANCE MONITORING SITES*
Stage 2
Compliance
Monitoring
Site ID
Stage 1 #2
Standard
Monitoring #6
Stage 1 #1
Standard
Monitoring #3
Standard
Monitoring #5
Standard
Monitoring #8
Site Type
B Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
B Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
B Stage 1 DBPR
B Highest TTHM
D Highest HAAS
D Stage 1 DBPR
B Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
B Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
D Highest TTHM
D Highest HAAS
D Stage 1 DBPR
Justification
Stage 1 DBPR location #2 had the highest TTHM
LRAA.
Standard Monitoring location #6 had the highest
HAAS LRAA.
As one of the two Stage 1 DBPR maximum
residence time sites was already selected as a
Stage 2 DBPR location #1 was chosen as the
third Stage 2 DBPR compliance monitoring
location.
Standard monitoring location #3 had the next
highest TTHM LRAA among the locations not
previously selected.
Standard monitoring location #5 had the next
highest TTHM LRAA among the locations not
previously selected.
Standard monitoring locations #7 and #8 had
similar HAAS LRAAs among locations not
previously selected. Standard monitoring
location #8 was chosen for geographic
representation as this quadrant of the distribution
has no sample sites.
Attach additional copies of this sheet if you need more room.
IDSE Guidance Manual for the Final Stage 2 DBPR 1-17
January 2006
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Form 7: IDSE Report for Standard Monitoring
Page 8 of 9
V. PEAK HISTORICAL MONTH AND PROPOSED STAGE 2 DBPR COMPLIANCE
MONITORING SCHEDULE
A.
B.
Peak Historical Month* August
Is Your Peak Historical Month the Same as in Your IDSE Standard Monitoring
Plan?
Yes
D No
If no, explain how you selected your new peak historical month (attach
additional sheets if needed)
C. Proposed Stage 2 DBPR Compliance Monitoring Schedule*
Stage 2
Compliance
Monitoring
Site ID
Stage 1 #2
SM#6
Stage 1 #1
SM#3
SM#5
SM#8
Projected Sampling Date (date or week)1
period 1
5/2012 3rd week
5/2012 3rd week
5/2012 3rd week
5/2012 3rd week
5/2012 3rd week
5/2012 3rd week
period 2
8/2012 3rd week
8/2012 3rd week
8/2012 3rd week
8/2012 3rd week
8/2012 3rd week
8/2012 3rd week
period 3
11/2012 3rd week
11/2012 3rd week
11/2012 3rd week
11/2012 3rd week
11/2012 3rd week
11/2012 3rd week
period 4
2/2013 3rd week
2/2013 3rd week
2/2013 3rd week
2/2013 3rd week
2/2013 3rd week
2/2013 3rd week
1 period = monitoring period. Complete for the number of monitoring periods from Section
I I.C.
Attach additional copies of this sheet if you need more room.
IDSE Guidance Manual for the Final Stage 2 DBPR 1-18
January 2006
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Form 7: IDSE Report for Standard Monitoring
Page 9 of 9
VI. DISTRIBUTION SYSTEM SCHEMATIC*
ATTACH a schematic of your distribution system if it has changed since you submitted
your Standard Monitoring Plan (Form 6).
VII. ATTACHMENTS
D Additional sheets for explaining how and why you deviated from your standard
monitoring plan (Section III).
D Additional sheets for Standard Monitoring Results (Section III). REQUIRED if you are
a subpart H system serving more than 49,999 people or a ground water system
serving more than 499,999 people.
D Additional sheets for Stage 2 DBPR Compliance Monitoring Sites (Section IV).
REQUIRED if you are a subpart H system serving more than 249,999 people.
D Additional sheets for explaining how you selected the peak historical month (Section
V).
D Additional sheets for proposed Stage 2 DBPR peak historical month and compliance
monitoring schedule (Section V). REQUIRED if you are a subpart H system serving
more than 249,999 people.
n Distribution system schematic* (Section VI). REQUIRED if it has changed from
your approved IDSE standard monitoring plan.
D Compliance calculation procedures (for Stage 2 Compliance Monitoring Plan)
Total Number of Pages in Your Report: 9
Note: Fields with an asterisk (*) are required by the Stage 2 DBPR
IDSE Guidance Manual for the Final Stage 2 DBPR 1-19 January 2006
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IDSE Guidance Manual for the Final Stage 2 DBPR 1-20 January 2006
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