Simultaneous Compliance Guidance Manual for the LT2 and Stage 2 DBP Rules

462 Pages·2007·3.36 MB·English

______________________________________________________________________________________
SIMULTANEOUS COMPLIANCE GUIDANCE MANUAL
FOR THE LONG TERM 2 AND STAGE 2 DBP RULES

Office of Water (4601)
EPA 815-C-08-001
March 2007
U.S. Environmental Protection Agency
Office of Water (4601)
1200 Pennsylvania Avenue NW
Washington, DC 20460
EPA 815-C-08-001
http://www.epa.gov/safewater/disinfection/stage2/compliance.html
March 2007
Purpose:

The purpose of this guidance manual is to provide technical information for water
systems and states to assist them with complying with the Stage 2 Disinfectant and Disinfection
Byproducts Rule, the Long Term 2 Enhanced Surface Water Treatment Rule, and other Safe
Drinking Water Act (SDWA) regulations. 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 its use in a particular
situation. Although this manual describes many methods for complying with SDWA
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 Ground Water and
Drinking Water and was prepared by The Cadmus Group, Inc. and HDR, Inc. Questions
concerning this document should be addressed to:

Sarah Bahrman
Office of Ground Water & Drinking Water
U.S. Environmental Protection Agency
Mail Code 4607M
1200 Pennsylvania Avenue NW
Washington, DC 20460-0001
Email: [email protected]
Simultaneous Compliance Guidance Manual 3 March 2007
For the Long Term 2 and Stage 2 DBP Rules
Acknowledgments:

Gary Burlingame ― Philadelphia Water Department
Chris Hill ― Malcolm Pirnie, Inc.
Rick Sakaji ― California Department of Health Services
David Schendel ― Malcolm Pirnie, Inc.
Ann Arbor Utilities
City of Englewood, Colorado
Gulf Coast Water Authority
City of Higginsville, Missouri
Kansas City Water Services
Owenton Water Works and Kentucky American TriVillage
Palm Beach County Water Utilities Department
City of Poughkeepsie, New York
Skagit County Public Utility District #1
City of Tampa, Florida
Washington Suburban Sanitary Commission
Village of Waterloo, New York
City of Wilmington, North Carolina

Simultaneous Compliance Guidance Manual 4 March 2007
For the Long Term 2 and Stage 2 DBP Rules
Table of Contents

Table of Contents...........................................................................................................................i
List of Exhibits...............................................................................................................................v
List of Abbreviations and Acronyms.........................................................................................vi

1. Introduction...........................................................................................................................1-1
1.1 What is the purpose of this guidance manual?.............................................................1-1
1.2 What is “Simultaneous Compliance”?..........................................................................1-2
1.3 Does this manual address compliance with environmental regulations other
than SDWA regulations?..............................................................................................1-2
1.4 Who should use this guidance manual? How should it be used?................................1-2
1.5 How is this manual organized?.....................................................................................1-7
1.6 Can I rely on this guidance manual alone to make compliance decisions?................1-11
1.7 Are there quick references I can use to screen for potential simultaneous
compliance problems?................................................................................................1-11
1.8 Where can I get help achieving simultaneous compliance?.......................................1-12
1.9 What additional resources are available?....................................................................1-12

2. Quick Reference Materials for Simultaneous Compliance...............................................2-1

3. Improving and Optimizing Current Operations...............................................................3-1
3.1 Source Management.....................................................................................................3-2
3.1.1 Advantages of Source Management................................................................3-4
3.1.2 Potential Operational and Simultaneous Compliance Issues Associated
with Source Management Changes.................................................................3-5
3.1.3 Recommendations for Gathering More Information.....................................3-10
3.2 Distribution System Best Management Practices.......................................................3-11
3.2.1 Advantages of Distribution System BMPs....................................................3-16
3.2.2 Potential Operational and Simultaneous Compliance Issues Associated
with Distribution System BMPs....................................................................3-17
3.2.3 Recommendations for Gathering More Information.....................................3-19
3.3 Moving the Point of Chlorination...............................................................................3-21
3.3.1 Advantages of Moving the Point of Chlorination.........................................3-22
3.3.2 Potential Operational and Simultaneous Compliance Issues
Associated with Moving the Point of Chlorination......................................3-23
3.3.3 Recommendations for Gathering More Information.....................................3-28
3.4 Decreasing pH.............................................................................................................3-30
3.4.1 Advantages of Decreasing pH.......................................................................3-30
3.4.2 Potential Operational and Simultaneous Compliance Issues Associated
with Decreasing pH.......................................................................................3-32
3.4.3 Recommendations for Gathering More Information.....................................3-35
3.5 Reducing Chlorine Dose under Warm Water Conditions..........................................3-37
3.5.1 Advantages of Reducing Chlorine Dose under Warm Water Conditions.....3-37
3.5.2 Potential Operational and Simultaneous Compliance Issues Associated
with Reducing Chlorine Dose under Warm Water Conditions.....................3-38
3.5.3 Recommendations for Gathering More Information.....................................3-39
3.6 Modifying Pre-sedimentation Basin Operations.........................................................3-41
Simultaneous Compliance Guidance Manual i March 2007
For the Long Term 2 and Stage 2 DBP Rules
Table of Contents (continued)

3.6.1 Advantages of Modifying Pre-sedimentation Basin Operations...................3-41
3.6.2 Potential Operational and Simultaneous Compliance Issues Associated
with Modifying Pre-sedimentation Basin Operations...................................3-42
3.6.3 Recommendations for Gathering More Information.....................................3-43
3.7 Enhanced Coagulation................................................................................................3-44
3.7.1 Advantages of Enhanced Coagulation..........................................................3-44
3.7.2 Potential Operational and Simultaneous Compliance Issues Associated
with Enhanced Coagulation...........................................................................3-46
3.7.3 Recommendations for Gathering More Information.....................................3-51
3.8 Enhanced Softening....................................................................................................3-53
3.8.1 Advantages of Enhanced Softening..............................................................3-54
3.8.2 Potential Operational and Simultaneous Compliance Issues Associated
with Enhanced Softening...............................................................................3-55
3.8.3 Recommendations for Gathering More Information.....................................3-58

4. Installing New Total Organic Carbon or Microbial Removal Technologies...................4-1
4.1 Granular Activated Carbon...........................................................................................4-1
4.1.1 Advantages of GAC........................................................................................4-2
4.1.2 Potential Operational and Simultaneous Compliance Issues Associated
with Using GAC..............................................................................................4-3
4.1.3 Recommendations for Gathering More Information.......................................4-6
4.2 Microfiltration/Ultrafiltration.......................................................................................4-8
4.2.1 Advantages of MF/UF.....................................................................................4-8
4.2.2 Potential Operational and Simultaneous Compliance Issues Associated
with MF/UF.....................................................................................................4-9
4.2.3 Recommendations for Gathering More Information.....................................4-11
4.3 Nanofiltration..............................................................................................................4-13
4.3.1 Advantages of Nanofiltration........................................................................4-13
4.3.2 Potential Operational and Simultaneous Compliance Issues Associated
with Nanofiltration........................................................................................4-14
4.3.3 Recommendations for Gathering More Information.....................................4-17
4.4 Other Microbial Removal Technologies.....................................................................4-19
4.4.1 Advantages....................................................................................................4-20
4.4.2 Potential Operational and Simultaneous Compliance Issues........................4-21
4.4.3 Recommendations for Gathering More Information.....................................4-23

5. Alternative Disinfection Strategies......................................................................................5-1
5.1 Chloramines..................................................................................................................5-1
5.1.1 Advantages of Chloramines............................................................................5-1
5.1.2 Potential Operational and Simultaneous Compliance Issues Associated
with Chloramines............................................................................................5-3
5.1.3 Recommendations for Gathering More Information.....................................5-10
5.2 Ozonation....................................................................................................................5-13
5.2.1 Advantages of Ozonation..............................................................................5-13
5.2.2 Potential Operational and Simultaneous Compliance Issues Associated
with Ozonation..............................................................................................5-15
5.2.3 Recommendations for Gathering More Information.....................................5-21
5.3 Ultraviolet Light (UV)................................................................................................5-24
Simultaneous Compliance Guidance Manual ii March 2007
For the Long Term 2 and Stage 2 DBP Rules
Table of Contents (continued)

5.3.1 Advantages of UV.........................................................................................5-24
5.3.2 Potential Operational and Simultaneous Compliance Issues Associated
with UV Disinfection....................................................................................5-25
5.3.3 Recommendations for Gathering More Information.....................................5-30
5.4 Chlorine Dioxide.........................................................................................................5-32
5.4.1 Advantages of Chlorine Dioxide...................................................................5-32
5.4.2 Potential Operational and Simultaneous Compliance Issues Associated
with Chlorine Dioxide Use............................................................................5-34
5.4.3 Recommendations for Gathering More Information.....................................5-39
5.5 Primary and Residual Disinfectant Use......................................................................5-41
5.5.1 Noteworthy Issues About Disinfectant Combinations..................................5-44
5.5.2 Recommendations for Gathering More Information.....................................5-44

6. Making Compliance Decisions.............................................................................................6-1
6.1 Introduction...................................................................................................................6-1
6.2 Issues to Consider When Making a Compliance Decision...........................................6-2
6.3 Tools for Gathering Information...................................................................................6-7
6.3.1 Water Quality Monitoring...............................................................................6-7
6.3.2 Hydraulic and Water Quality Modeling for Distribution System...................6-9
6.3.3 Desktop Evaluations......................................................................................6-11
6.3.4 Bench-Scale Testing......................................................................................6-12
6.3.5 Pilot Testing..................................................................................................6-15
6.3.6 Full-Scale Applications.................................................................................6-16
6.3.7 Cost Estimation.............................................................................................6-18
6.3.8 Community Preferences................................................................................6-20
6.4 Basic Approach for Implementing Regulatory Compliance Projects.........................6-21

7. References..............................................................................................................................7-1
7.1 References Organized by Topic....................................................................................7-1
7.1.1 General............................................................................................................7-1
7.1.2 Formation and Control of Chlorinated DBPs..................................................7-9
7.1.3 Corrosion.......................................................................................................7-10
7.1.4 Source Management......................................................................................7-13
7.1.5 Distribution System Management.................................................................7-14
7.1.6 Problem Organisms in Water Treatment.......................................................7-16
7.1.7 Pre-sedimentation..........................................................................................7-17
7.1.8 Enhanced Coagulation and Enhanced Softening...........................................7-17
7.1.9 GAC...............................................................................................................7-19
7.1.10 Membranes....................................................................................................7-20
7.1.11 Riverbank Filtration......................................................................................7-21
7.1.12 Chloramines...................................................................................................7-22
7.1.13 Ozone.............................................................................................................7-25
7.1.14 Ultraviolet Light............................................................................................7-27
7.1.15 Chlorine Dioxide...........................................................................................7-28
7.1.16 Tools for Gathering More Information.........................................................7-29
7.1.17 Chlorination...................................................................................................7-35
7.2 Comprehensive List of References.............................................................................7-38

Simultaneous Compliance Guidance Manual iii March 2007
For the Long Term 2 and Stage 2 DBP Rules
Table of Contents (continued)

Appendices

Appendix A. Summary of Pertinent Drinking Water Regulations......................................A-1
Appendix B. Case Studies....................................................................................................B-1
Appendix C. Guidance for Evaluating Potential Impacts of Treatment Changes on
Distribution Systems.......................................................................................C-1
Appendix D. Tools for Evaluating Impacts of Treatment Changes on Lead and
Copper Rule Compliance ..............................................................................D-1
Appendix E. Innovative Management Tools for Achieving Simultaneous Compliance.....E-1
Appendix F. Considerations for Systems Complying with the Ground Water Rule...........F-1

Simultaneous Compliance Guidance Manual iv March 2007
For the Long Term 2 and Stage 2 DBP Rules
List of Exhibits

Exhibit 1.1 Existing SDWA Regulations as of March, 2007....................................................1-4
Exhibit 1.2 Organization of the Chapters..................................................................................1-8
Exhibit 1.3 Organization of the Appendices.............................................................................1-9
Exhibit 1.4 Treatment Technologies and Operational Changes Addressed in this
Guidance Manual.................................................................................................1-10
Exhibit 1.5 EPA Guidance Manuals under Development.......................................................1-14

Exhibit 2.1 Checklist for Identifying Key Operational and Simultaneous
Compliance Issues..................................................................................................2-2
Exhibit 2.2 Technology Alternatives and How They Potentially Affect Water Quality..........2-3
Exhibit 2.3 Stage 2 DBPR and LT2ESWTR Compliance Technologies:
Summary of Benefits and Potential Conflicts........................................................2-6
Exhibit 2.4 Potential Operational Issues for Different Treatment Modifications...................2-12
Exhibit 2.5 Case Studies in this Guidance Manual and Issues they Address.........................2-13
Exhibit 2.6 Tools for Gathering System-Specific Information on Different Compliance
Techniques...........................................................................................................2-16

Exhibit 3.1 Typical Chlorine Points of Application and Uses................................................3-21
Exhibit 3.2 Percent Reduction in DBP Formation by Moving Point of Chlorination............3-22
Exhibit 3.3 Effects of pH Changes on CT Required for 0.5-Log Inactivation of
Giardia lamblia....................................................................................................3-31
Exhibit 3.4 Impacts of pH on Formation of DBPs..................................................................3-31
Exhibit 3.5 Required CT for 0.5-Log Inactivation of Giardia lamblia by
Free Chlorine at pH 7.0........................................................................................3-38
Exhibit 3.6 Effect of the Change of Water Quality Parameters Due to Enhanced
Softening on Corrosion of Piping System Materials............................................3-55

Exhibit 5.1 Comparison of Required CT (mg-min/L) values for Inactivation of
Viruses and Giardia by Free Chlorine and Monochloramine at
pH 7 and 10oC........................................................................................................5-8
Exhibit 5.2 Required CT values (mg-min/L) for Chemical Disinfectants at 10°C.................5-14
Exhibit 5.3 Ratio of CT values for Inactivation of Viruses and Cryptosporidium at 10°C....5-27
Exhibit 5.4 Required CT Values for Inactivation of Microorganisms by Chlorine
Dioxide Compared with Other Chemical Disinfectants at 10oC and
pH 6-9 (in mg-min/L)...........................................................................................5-33
Exhibit 5.5 Effect of Temperature on the CT Required for Cryptosporidium Inactivation
by Chlorine Dioxide.............................................................................................5-36
Exhibit 5.6 Summary of Potential Benefits and Adverse Effects Associated with Different
Combinations of Primary and Residual Disinfectants.........................................5-42

Exhibit 6.1 Issues to Consider When Deciding How to Comply with Stage 2 DBPR
and/or LT2ESWTR................................................................................................6-3
Exhibit 6.2 Application of Information Gathering Tools at Various Project
Implementation Stages.........................................................................................6-22

Simultaneous Compliance Guidance Manual v March 2007
For the Long Term 2 and Stage 2 DBP Rules
List of Abbreviations and Acronyms (continued)

List of Abbreviations and Acronyms

AOC assimilable organic carbon
APHA American Public Health Association
AMTA American Membrane Technology Association
As(III) arsenite
As(V) arsenate
AWWA American Water Works Association
AwwaRF American Water Works Association Research Foundation
BAT best available technology
BLS below land surface
BMPs best management practices
BDOC biodegradable dissolved organic carbon
C disinfectant concentration in mg/L (in CT calculations)
CDPHE Colorado Department of Health and Environment
CFE combined filter effluent
CIS Customer Information System
CO carbon dioxide
2
CaCO calcium carbonate
3
CPE comprehensive performance evaluation
CT disinfectant concentration x contact time, a measure of
disinfection performance
CTA comprehensive technical assistance
CWS community water system
DBP disinfection byproduct
DBPR Disinfectants and Disinfection Byproducts Rule
DCWASA Washington D.C. Water and Sewage Authority
DE diatomaceous earth
DO dissolved oxygen
DIC dissolved inorganic carbon
DOC dissolved organic carbon
DOP demonstration of performance
EBCT empty bed contact time
EPA U.S. Environmental Protection Agency
FBRR Filter Backwash Recycling Rule
GAC granular activated carbon
GPM gallons per minute
GWR Ground Water Rule
GWUDI ground water under the direct influence of surface water
H CO carbonic acid
2 3
HCO - bicarbonate
3
HAA haloacetic acid
HAA5 the sum of five HAA species (monochloroacetic,
dichloroacetic, trichloroacetic, monobromoacetic, and
Simultaneous Compliance Guidance Manual vi March 2007
For the Long Term 2 and Stage 2 DBP Rules