## EXPLANATION OF THIS DOCUMENT

PLEASE READ

This is a draft of the Proposed Revised Total Colifor m Rule Assessments and Corrective

Actions Guidance Manual (Proposed RTCR A/CA GM). As such, th ere are a couple of things

readers must keep in mind:

• This was developed in response to stakeholde rs’ request. Stakeholders requested that a

draft of the guidance manual be available during the public comment period of the

Proposed Revised Total Coliform Rule (RTCR) to help them better prepare their

comments on the proposed rule.

• This is based on the requirements of a proposed rule. Between now and when the rule is

finalized, the requirements may change de pending on the comments EPA receives on the

proposed rule during the public comment period. Accordingly, EPA will make the

necessary changes to the guidance manual to reflect the new requirements of the final

rule.

• EPA is not taking any comments on the proposed rule via this draf t guidance manual.

Any comments on the proposed RTCR must be made through www.regulations.gov

(search for Docket number EPA-HQ-OW-2008- 0878). The Federal Register notice for

the proposed rule also includes additional methods for submitting comments on the

proposed rule (75 FR 40926, July 14, 2010).

EPA is interested in obtaining stakeholder input in further developing a guidance manual that

would be of most use to public water systems a nd primacy agencies. EPA, therefore, welcomes

comments on any aspect of the draft Proposed RTCR A/CA GM (e.g., formatting, organization,

content, etc.), but specifically requests comment on the following:

• Should systems be encouraged to submit assessment forms electronically?

• Are there other causes of total coliforms/ E. coli contamination that should be addressed

in this document?

• Are there any other potential corrective actions that have not been noted?

• Are there other examples of assessment in Appendix B that people would like to see

discussed instead?

• Should any other AWWA Standards (or other references) be include d? Are there ones

that need to be deleted?

• Should EPA consider revising the example assessment forms in Appendix A? If so,

please provide suggestions for impr ovements/changes to the forms.

Please submit your comments to prtcr_acaguide@epa.gov by November 30, 2010.

Proposed Revised Total Coliform Rule August 2010

Assessments and Corrective Actions Guidance Manual

Draft

## THIS PAGE INTENTION ALLY LEFT BLANK

# PROPOSED REVISED TOTAL COLIFORM

RULE

Assessments and Corrective Actions Guidance

Manual

Draft

### Office of Water (4607M)

EPA 815-D-10-001

August 2010

www.epa.gov/safewater

### DRAFT

Proposed Revised Total Coliform Rule i August 2010

Assessments and Corrective Actions Guidance Manual 

## DISCLAIMER

This manual is intended to provide inform ation to assist public water systems in

complying with Level 1 and Level 2 assessment and corrective action requirements under the

proposed Revised Tota l Coliform Rule.

This guidance is not a substitute for applicable legal requirements, nor is it a regulation

itself. Thus, it does not impose legally-bindi ng requirements on any party, including EPA,

States, or the regulated community. While EPA has made every effort to ensure the accuracy of

the discussion in this guidance, the obligations of the regulated community are determined by

statutes, regulations, or other le gally binding requirements. In th e event of a conflict between the

discussion in this document and any statute or regulation, the statute or regulation would be

binding.

Interested parties are free to raise ques tions and objections to the guidance and the

appropriateness of using it in a particular situation.

Although this manual describes suggesti ons for complying with proposed RTCR

requirements, the guidance presented here may not be appropriate fo r all situations, and

alternative approaches may provide satisfactory performance.

Mention of trade names or commercial produc ts does not constitute an EPA endorsement

or recommendation for use.

Questions regarding this docum ent should be addressed to:

Julie Javier

U.S. EPA Office of Ground Water and Drinking Water

Standards and Risk Management Division

1200 Pennsylvania Avenue, N.W. 4607M

Washington, DC 20460

Javier.Julie@epa.gov

Phone: 202-564-2335

Fax: 202-564-3767

### DRAFT

Proposed Revised Total Coliform Rule ii August 2010

Assessments and Corrective Actions Guidance Manual 

## ACKNOWLEDGMENTS

• American Water Works Association

• Association of State Dri nking Water Administrators

• Association of Metropolitan Water Agencies

• New Hampshire Department of Environmental Services

• California Department of Public Health

• Park Water Company

### DRAFT

Proposed Revised Total Coliform Rule iii August 2010

Assessments and Corrective Actions Guidance Manual 

## CONTENTS

1. Introduction and Scope of this Manual ......................................................................................... ..... 1-1

1.1 Organization of Document ...................................................................................................... ... 1-1

1.2 Nature of Microbial Indicators ................................................................................................ ... 1-2

1.3 Occurrence of Fecal Contamination and Waterborne Pathogens ............................................... 1-2

1.4 Causes of Coliforms and E. coli in the Distribution System ...................................................... 1-3

1.5 Other Relevant Guidance Documents ........................................................................................ 1-5

2. Summary of the Proposed Revised Total Coliform Rule ................................................................... 2-1

3. Assessments ................................................................................................................... .................... 3-1

3.1 Sanitary Defects .............................................................................................................. ........... 3-2

3.2 Level 1 Assessments ........................................................................................................... ....... 3-2

3.3 Level 2 Assessments ........................................................................................................... ....... 3-3

3.4 Assessment Forms .............................................................................................................. ....... 3-6

3.5 Timeline for Assessments a nd Corrective Actions .................................................................... 3-7

3.6 Assessment Elements ........................................................................................................... ...... 3-7

3.6.1 Operational Data Review (Q uestions 1 and 2) ........................................................... 3-7

3.6.2 Sample Site and Protocol Evalua tion (Questions 3 and 4) ....................................... 3-13

3.6.3 Water System Component Evaluati ons (Questions 5 to 10) .................................... 3-14

3.7 Qualifications of Assessors ................................................................................................... ... 3-19

3.7.1 Level 1 Assessors ..................................................................................................... 3-20

3.7.2 Level 2 Assessors ..................................................................................................... 3-20

3.8 Assessments and Sanitary Surveys .......................................................................................... 3-2 1

4. Corrective Actions ............................................................................................................ ................. 4-1

4.1 Common Causes ................................................................................................................. ....... 4-1

4.2 Common Correctiv e Actions ..................................................................................................... 4-2

4.2.1 Disinfection ................................................................................................................ 4 -5

4.2.2 Flushing ...................................................................................................................... 4-6

4.2.3 Replacement / Repair of Distribution System Components ....................................... 4-6

4.2.4 Maintenance of Adequate Pressure ............................................................................ 4-9

4.2.5 Maintenance of Appropriate Hy draulic Residence Time ......................................... 4-11

4.2.6 Maintenance of Storage Facility .............................................................................. 4-13

4.2.7 Implementation or Upgrade of a Cross-connection Control and Backflow Prevention

Program .................................................................................................................. ..4- 14

4.2.8 Sampler Training ...................................................................................................... 4-15

4.2.9 Addition or Upgrade of On-line Monitoring and Control ........................................ 4-15

4.2.10 Addition of Security Measures................................................................................. 4-16

4.2.11 Development and Implementation of an Operations Plan ....................................... 4-16

4.3 Best Practices ................................................................................................................ ........... 4-17

4.4 Simultaneous Compliance Issues ............................................................................................. 4- 19

5. References .................................................................................................................... ...................... 5-1

Appendix A ...................................................................................................... Example Ass essment Forms

Appendix B ....................................................................................... Examples of Completed Asse ssments

Appendix C ................................................................... Common Sanitary Defects and Corrective Actions

Appendix D ......................................................... Industry Standards fo r Operating a Public Water System

### DRAFT

Proposed Revised Total Coliform Rule iv August 2010

Assessments and Corrective Actions Guidance Manual

### DRAFT

Proposed Revised Total Coliform Rule v August 2010

Assessments and Corrective Actions Guidance Manual 

## ACRONYMS

AIP Agreement in Principle

AMWA Association of Metropolitan Water Agencies

APHA American Public Health Association

ASDWA Association of State Dr inking Water Administrators

AWWA American Water Works Association

AWWARF American Water Works Association Research Foundation

CCCBFP Cross-Connection Control and Backflow Prevention

CFR Code of Federal Regulations

CWS Community Water Systems

DBP Disinfection Byproducts

EC E. coli

EC+ E. coli- Positive

EPA Environmental Protection Agency

FR Federal Regulations

GW Ground Water

GWR Ground Water Rule

GWUDI Ground Water Under the Direct Influence of Surface Water

HAA5 Haloacetic Acids (5)

HPC Heterotrophic Plate Count

HRT Hydraulic Residence Time

IESWTR Interim Enhanced Surface Water Treatment Rule

MCL Maximum Contaminant Level

MCLG Maximum Contaminant Level Goal

NCWS Non-community Water System

NPS Nominal Pipe Size

O&M Operation and Maintenance

PN Public Notification

PWS Public Water System

RTCR Revised Total Coliform Rule

SCADA Supervisory Contro l And Data Acquisition

SOP Standard Operating Procedures

TC Total Coliforms

TC+ Total Coliform-Positive

TCR Total Coliform Rule

TCRDSAC Total Coliform Rule / Distri bution System Advisory Committee

TT Treatment Technique

TTHM Total Trihalomethanes

US United States

USEPA United States Environmental Protection Agency

### DRAFT

Proposed Revised Total Coliform Rule 1-1 August 2010

Assessments and Corrective Actions Guidance Manual 

## 1. Introduction and Scope of this Manual 1

2

3



### Under the proposed Revised Total Colifor m Rule (RTCR) (USEPA 2010b), a public 4



### water system (PWS) that is vulnerable to micr obial contamination (as indicated by its monitoring 5



### results) is required to conduct a ssessment and corrective action of the system to identify and 6



### correct any sanitary defects 1 

### in the distribution system or treat ment processes. This document 7



### provides PWSs with guidance on implementi ng the assessment a nd corrective action 8



### requirements of the proposed RTCR. 9

10



### 1.1 Organization of Document 11

12



### The document is organized as follows: 13

14



### • Chapter 1 – Introduction and Scope of this Manual. This chapter introduces the 15



### guidance manual, summarizes each section of the document, discusses the nature of 16



### microbial indicators and their relation to wa terborne pathogens, discusses the causes 17



### of coliforms and E. coli in the distribution system, and provides a description of other 18



### relevant guidance documents and that may be useful to the reader. 19

20



### • Chapter 2 – Summary of the Proposed Revised Total Coliform Rule. This 21



### chapter summarizes the requirements of the proposed RTCR. 22

23



### • Chapter 3 – Assessments. This chapter presents a de tailed overview of the Level 1 24



### and Level 2 assessment requirements under the proposed RTCR and provides 25



### guidance to assist PWSs and States 2 

### in the implementation of these requirements. 26



### The chapter also includes di scussions on the differences between Level 1 and Level 2 27



### assessments; the elements of assessments; assessment forms; sources of data or 28



### information for completing assessment forms and recommendations on how systems 29



### should complete assessments given system attributes (e.g., system size, type, 30



### disinfection status, etc.); and qualifications of assessors. 31

32



### • Chapter 4 – Corrective Action. This chapter discusses requirements and provides 33



### guidance related to the identification and corr ection of sanitary defects, particularly 34



### those in the distribution syst em. It also provides guidan ce related to actions that 35



### could be taken regardless of the outcome of the assessments. 36

37



### • Appendix A – Example Assessment Forms 38

39



### • Appendix B – Examples of Completed Assessments 40

1 A defect that could provide a pathway of entry for microbial c ontamination into the distribution system or that is indicative of a

failure or imminent failure in a barrier that is already in place. Proposed RTCR § 141.851. Se e Chapter 3.1 of this document for

a more detailed discussion of sanitary defects.

2 In this document, “State” is used to generally refer to the primacy agency, whether it be the State agency, the Tribal

government, or EPA. A primacy agency is the entity that ha s the primary responsibility for administrating and enforcing

regulations under the Safe Drinking Water Act (SDWA) in a given jurisdiction. In many cases, the State agency is the primacy

agency.

### DRAFT

Proposed Revised Total Coliform Rule 1-2 August 2010

Assessments and Corrective Actions Guidance Manual 1



### • Appendix C – Common Sanitary Defects and Corrective Actions 2

3



### • Appendix D – Industry Standards for Operating a Public Water System 4

5



### 1.2 Nature of Microbial Indicators 6

7



### The proposed RTCR aims to increase public health protection th rough the reduction of 8



### potential pathways of entry for fecal contaminat ion into the distribution system. Since these 9



### potential pathways represent vulnerabilities in the distribution system whereby fecal 10



### contamination and/or waterborne pathogens, incl uding bacteria, viruses a nd parasitic protozoa 11



### could possibly enter the system, the reduction of these pathways in general should lead to 12



### reduced exposure and associated risk from these contaminants. Fecal contamination and 13



### waterborne pathogens can cause a variety of illne sses, including acute gastrointestinal illness 14



### (AGI) with diarrhea, ab dominal discomfort, nausea, vomiting, and other symptoms. As stated 15



### earlier, under the proposed RTCR, a PWS that is vulnerable to fecal contamination (as indicated 16



### by its monitoring results for total coliforms and E. coli ) is required to conduc t an assessment of 17



### the system to identify and correct any sanitary defects. 18

19



### Under the proposed RTCR, EPA uses total colifo rms as indicators of the integrity of the 20



### distribution system, and E. coli as an indicator of the presence of fecal contamination. 21

22



### Total coliforms are a group of cl osely related bacteria that, with few exceptions, are not 23



### harmful to humans. Coliforms are abundant in th e feces of warm-blooded animals, but can also 24



### be found in aquatic environments, in soil, a nd on vegetation. Colif orm bacteria may be 25



### transported to surface water by run-off or to gr ound water by infiltration. Total coliforms are 26



### common in ambient water and may be injured by environmental stresses such as lack of 27



### nutrients, and water treatments such as chlori ne disinfection, in a manner similar to most 28



### bacterial pathogens and many viral enteric pa thogens (including fecal pathogens). EPA 29



### considers total coliforms to be a useful indicator that a potenti al pathway exists through which 30



### fecal contamination can enter the distribution syst em. The absence (versus the presence) of total 31



### coliforms in the distribution system indicates a reduced likelihood that fecal contamination 32



### and/or waterborne pathogens are oc curring in the distribution system. 33

34



### Under the proposed RTCR, each total co liform-positive sample is assayed for E. coli

. E. 35



### coli is a more restricted group of coliform bacteria that almost al ways originate in the human or 36



### animal gut (Edberg et al. 2000). Thus, E. coli is used as an indicator of fecal contamination. 37

38



### 1.3 Occurrence of Fecal Contamina tion and Waterborne Pathogens 39

40



### Fecal contamination is a very general term that includes all of the organisms found in 41



### feces, both pathogenic and nonpathogenic. Fecal c ontamination can occur in drinking water both 42



### through use of contaminated source water without su fficient treatment as well as direct intrusion 43



### of fecal contaminants into the drinking water distribution system. Lieberman et al. (1994) 44



### discuss the general association between fecal c ontamination and waterborne pathogens. Biofilms 45



### in distribution systems may harbor waterborne bacterial pathogens and accumulate enteric 46



### viruses and parasitic protozoa (S kraber et al. 2005; Helmi et al . 2008). Waterborne pathogens in 47



### biofilms may have entered the distribution syst em as fecal contamination from humans or 48



### animals. 49

### DRAFT

Proposed Revised Total Coliform Rule 1-3 August 2010

Assessments and Corrective Actions Guidance Manual 1



### Co-occurrence of indicators and waterborne pathogens is difficult to measure. The 2



### analytical methods approved by EPA to assay for E. coli are able to detect indicators of fecal 3



### contamination but do not specifically identify most of the pathogenic E. coli strains. Specialized 4



### assays and methods are used to identify waterborne pathogens, including pathogenic E. coli such 5



### as E. coli O157:H7, which is the primary cause of hemolytic uremic syndrome (HUS) in the 6



### United States (Rangel et al. 2005). Therefore, an E. coli- positive monitoring result is an 7



### indicator of fecal contamination (Edberg et al. 2000) but is not necessarily a measure of 8



### waterborne pathogen occurrence. However, st udies have shown that there is a general 9



### association between fecal contamination and wa terborne pathogens (Lieberman et al. 1994; 10



### Lieberman et al. 2002). Hence, E. coli is a meaningful indicator fo r fecal contamination and the 11



### potential presence of associated pathogen occurrence. 12

13



### 1.4 Causes of Coliforms and E. coli in the Distribution System 14

15



### There are numerous factors that can cont ribute to the presence of coliforms and E. coli in 16



### the distribution system. Coliform bacteria may be present in the distribution system if three 17



### conditions simultaneously occur: 18

19



### 1. A source of coliform bacteria; 20



### 2. A pathway into the distribution system or a breach in the system’s physical integrity; 21



### and 22



### 3. A mechanism that allows coliform bacteria to be carried on this pathway into the 23



### distribution system or that allows bacter ia within biofilms, corrosion tubercles or 24



### sediment to enter the water. 25

26



### Sources of coliform bacteria can include: 27

28



### • Soil and Water Surrounding Pipes – Coliform bacteria ar e common in the soil and 29



### water surrounding pipes, valves, and othe r distribution system infrastructure. 30



### • Biofilms and Microbial Growth - Coliforms may attach to or become enmeshed in 31



### biofilms on pipe walls in distribution sy stems, where they are protected from 32



### disinfectants. Over time, these coliforms (including their associated pathogens) may 33



### detach or slough from biofilms, causing pers istent detections and even waterborne 34



### disease. 35



### • Corrosion Tubercles - A number of cases have been documented showing the 36



### presence of coliform bacteria pres ent within corros ion tubercles. 37



### • Customer Connections - Customer connections and premise plumbing, such as the 38



### service line connections to schools, hosp itals, public and private housing, and other 39



### buildings, can be the source of coliform bact eria when a backflow event has occurred 40



### and water and contamination from the build ing pipes are drawn back into the public 41



### water distribution system, due to a change in pressure. 42



### • Materials Used in the Distribution System - In some instances, materials used in the 43



### distribution system can result in the presence of total coliforms through 44



### contamination of the materials prior to inst allation. Some materials may also support 45



### the growth of coliforms by providing nutrients for microbial growth. 46

### DRAFT

Proposed Revised Total Coliform Rule 1-4 August 2010

Assessments and Corrective Actions Guidance Manual 

### • Sediments - Sediment accumulation can provide a habitat for microbial growth in a 1



### distribution system. Furthermore, the se diments can protect the microbes from 2



### disinfectants. 3

4



### Pathways through which total coliform bacteria ca n enter the distribution system can be: 5

6



### • Finished Water Storage Facility Deficiencies - Storage tank deficiencies, such as 7



### vents without screens, inadequate hatches, access hatches that ar e not locked, physical 8



### openings in storage tank roofs, and lack of a cover, can result in the entry of 9



### contaminants. Microorganisms can also be introduced into underground storage 10



### facilities from surface water or ground water infiltration or runoff. 11



### • Unprotected Cross Connections - A cross connection is a pathway whereby a 12



### connection exists between a non-potable wa ter source and a potable source (e.g., the 13



### public water system). Backflow through a cross connection is the mechanism that 14



### allows non-potable water to enter the water distribution system. 15



### • Intrusion - Leaks or small holes in the pipe can provide a pathway for contaminants 16



### outside of a pipe to enter the distributi on system during low and negative pressure 17



### events (termed intrusion). Points through which intrusions can occur also include 18



### pipe fracture cracks, leaking joints, submerged air-vacuum /air-release valves and 19



### deteriorating seals. 20



### • Improper Main Installation, Repair, or Replacement - Main installation, repair, or 21



### replacement can result in a loss of pressure and exposure of the pipe interior to 22



### contaminated soil and runoff. If sanitary procedures are not followed, contaminants 23



### can be introduced into the pipes duri ng the main break repair process. 24

25



### Mechanisms that allow coliform bacteria to en ter the distribution system (assuming a 26



### source of contaminants and a pathway are present) or that allow bacteria to proliferate in the 27



### distribution system include the following: 28

29



### • Weather-Related Events - A range of different weathe r-related events can contribute 30



### to the increase of total coliforms, and someti mes fecal indicators in source waters. In 31



### other cases, coliforms may enter the distri bution system more directly. Types of 32



### weather-related events that have been attributed to indicator positive samples include 33



### significant rainfall events, droughts, and excessively warm or cold weather. 34



### • Treatment Breakthrough - Failure of the treatment ba rrier can lead to presence of 35



### coliforms in the distribution system. 36



### • Backflow – Backflow that allows the non-potable water to enter the potable system 37



### can occur either because of reduced pre ssure in the distribution system (termed 38



### backsiphonage) or the presence of increased pressure in the non-potable system 39



### (termed backpressure). 40



### • Hydraulic Conditions - Contaminant intrusion may o ccur if a very low or negative 41



### pressure occurs within the pipe. Low pre ssure conditions in th e distribution system 42



### can also allow a flow reversal or backflow of non-potable water to enter the system 43



### from a cross connection or othe r source such as intrusion. 44



### • Operations - Sudden velocity or flow directi on changes during operational activities 45



### within a distribution system can result in th e release of biofilms, scales, or sediments 46



### with microbial contamination These veloci ty and flow changes are sometimes related 47



### to fire fighting, valve exercising, and changing from one source to another. 48

### DRAFT

Proposed Revised Total Coliform Rule 1-5 August 2010

Assessments and Corrective Actions Guidance Manual 

### • Maintenance Practices – Maintenance practices such as flushing and line cleaning can 1



### affect the distributi on system water quality in a ne gative manner if not conducted 2



### properly and improper flushing can result in moving a contaminant further into the 3



### distribution system. 4



### • Retention Times - Long retention time in the distri bution system can reduce the levels 5



### of disinfectant residual and allow for th e deposition and accumulation of sediment. 6



### • Presence of Nutrients - Some materials or system operations can introduce nutrients 7



### such as carbon, nitrogen, and phosphorus to the distribution system that may support 8



### growth of total coliform bacteria. 9

10



### Additional information on the causes of coliforms and E. coli in the distribution system 11



### can be found in a series of issue pa pers and white papers located at 12



### http://www.epa.gov/safewater/disinfec tion/tcr/regulati on_revisions.html 13

14



### 1.5 Other Relevant Guidance Documents 15

16



### The reader can refer to the following guidance manuals and documents for more 17



### information that may be helpful in complyi ng with the assessment and corrective action 18



### requirements of the proposed RTCR. 19

20



### • Ground Water Rule Corrective Actions Guidance Manual (EPA 815-R-08-011; 21



### November 2008) 22



### http://www.epa.gov/safewater/disinfection/ gwr/pdfs/guide_gwr_correctiveaction.pdf 23



### This guide provides guidance in meeting the corrective action requirements of the 24



### Ground Water Rule. It provides assistance in determining the information that should 25



### be included in a public water system’s (PWS’s) corrective action plan and assists 26



### States and PWSs to select and implement corrective actions in response to significant 27



### deficiencies identified during a sanitary su rvey or in response to fecal contamination 28



### of the source water. 29

30



### • Sanitary Survey Guidance Manual for Ground Water Systems (EPA 815-R-08- 31



### 015; October 2008) 32



### http://www.epa.gov/safewater/disinfection/ gwr/pdfs/guide_gwr_sanitarysurvey.pdf 33



### This guide provides a brief review of the sa nitary survey regula tory provisions for 34



### ground water systems, give specific exampl es of what constitutes a significant 35



### deficiency, and provide a checklist of elem ents that should be evaluated during the 36



### course of a sanitary survey inspection. 37

38



### • Guidance Manual for Conducting Sanitary Surveys of Public Water Systems; 39



### Surface Water and Ground Water Under the Direct Influence (GWUDI) (EPA40



### 815-R-99-016; April 1999) 41



### http://www.epa.gov/safewater/mdbp/pdf/sansurv/sansurv.pdf 42



### This guide provides guidance on how to c onduct sanitary survey s of surface water 43



### systems and ground water under the direct influence (GWUDI) of surface water 44



### systems. It explains the elements of th e sanitary survey and presents general 45



### guidelines for evaluating the important components of each element. 46

47

48

### DRAFT

Proposed Revised Total Coliform Rule 1-6 August 2010

Assessments and Corrective Actions Guidance Manual 

### EPA is also planning to re vise the following documents for the final RTCR: 1

2



### • Total Coliform Rule: A Quick Reference Guide (EPA 816-F-01-035, September 3



### 2001) 4



### http://www.epa.gov/safewater/disin fection/tcr/pd fs/qrg_tcr_v11.pdf 5



### This two page guide provides the highlights of key rule requirements such as routine 6



### and repeat sampling requirements, routine monitoring frequencies, compliance and 7



### violation information, and public noti fication and reporting requirements. 8

9



### • A Small Systems Guide to the Total Co liform Rule: Monitoring Drinking Water 10



### to Protect Public Health (EPA 816-R-01-017A, June 2001) 11



### http://www.epa.gov/safewater/disinfection /tcr/pdfs/guide_tcr_smallystemsguide.pdf 12



### This guide provides information for commun ity water systems that serve fewer than 13



### 3,300 people. The guide describes the impor tance of monitoring drinking water to 14



### ensure its quality and protect public health and the monitoring that is required under 15



### the Total Coliform Rule. It outlines the steps water systems must take if their 16



### samples indicate the presence of coliform bact eria and a worksheet to help keep track 17



### of monitoring and follow-up actions. 18

19



### • Total Coliform Rule: A Handbook for Small Noncommunity Water Systems 20



### serving less than 3,300 persons: One of the Simple Tool s for Effective 21



### Performance (STEP) Guide Series (EPA 816-B-06-001, July 2006) 22



### http://www.epa.gov/safewater/disinfectio n/tcr/pdfs/stepguide _tcr_smallsys-3300.pdf 23



### This guide provides information for non-co mmunity water systems that serve fewer 24



### than 3,300 people. The guide describes th e monitoring that is required under the 25



### Total Coliform Rule. It outlines the steps water systems must take if their samples 26



### indicate the presence of co liform bacteria and a worksheet to help keep track of 27



### monitoring and follow-up actions. 28

29



### • Total Coliform Rule: A Handbook for Small Non-community Water Systems 30



### serving 1,000 Persons or Less 31



### A planned guide specifically for systems serving 1,000 persons or fewer given the 32



### reduced monitoring requirements that are particular to this group, possibly including 33



### one page pullouts and other simple tools for compliance assistance. 34

35

### DRAFT

Proposed Revised Total Coliform Rule 2-1 August 2010

Assessments and Corrective Actions Guidance Manual 

## 2. Summary of the Proposed Re vised Total Coliform Rule 1

2

3



### The proposed RTCR maintains and strengthens the objectives of the 1989 Total Coliform 4



### Rule (TCR) and is consistent with the recomm endations in the Agreement in Principle (AIP) 5



### signed by the Total Coliform Rule Distri bution System Advisory Committee (TCRDSAC) 3 

### . The 6



### rule objectives are: (1) to evaluate the effectiveness of treatment, (2) to determine the integrity of 7



### the distribution system, and (3) to signal the possible presence of f ecal contamination. The 8



### proposed revision better addresse s these objectives by requiring systems that may be vulnerable 9



### to fecal contamination (as indicated by their moni toring results) to do an assessment, to identify 10



### whether any sanitary defects 4 

### are present, and to correct the de fects. Therefore, EPA anticipates 11



### greater public health protection under the propos ed RTCR compared to the 1989 TCR because of 12



### its more preventive approach to identifying and fixing pr oblems that affect or may affect public 13



### health. The following table gives an overview of the key provisions of the proposed RTCR. For 14



### the full requirements of the propos ed RTCR, please refer to 40 CFR 5 

### Part 141, Subpart Y. 15

16



### Table 2.1 Summary of Pr oposed RTCR Requirements 17

Element Proposed RTCR requirements

Rule construct

§§ 141.52, 141.63,

141.854, 141.859 • The proposed RTCR sets an E. coli (EC) maximum contaminant level goal (MCLG)

of zero, and an EC maximum contaminant level (MCL) and a coliform treatment

technique (TT) based on total coliform (TC) and/or EC monitoring results.

• Compliance is based on the presence or abse nce of TC and EC and is determined each

calendar month the PWS serves water to th e public (or each calendar month that

sampling occurs for systems on reduced monitoring). See sections on “Assessment”

and “Violations and Public Notification (PN)” in this table for conditions when the

coliform TT and EC MCL are violated.

• Assessment and corrective action (if necessa ry) are required if PWS has a coliform

treatment technique trigger. See sections on “Assessment” and “Corrective Action” in

this table.

Transition from the

1989 TCR to the

RTCR

§§ 141.854 to 141.857 • PWSs continue on their existing TCR monitoring schedule when the RTCR is

effective.

• Ground water (GW) systems serving 1,000 or fewer persons remain on their TCR

schedule unless or until the conditions occur as described below or unless otherwise

directed by the State.

o Non-community water systems (NCWSs) on quarterly/annual monitoring remain

on that schedule unless/until they have an event that triggers increased monitoring.

See the section on “Increased Mon itoring (NCWS)” in this table.

o Community water systems (CWSs) on reduced monitoring remain on that schedule

unless/until they have an event that triggers them to go to routine monitoring. See

the section on “Return to Routine Monitoring (CWS)” in this table.

o Monitoring schedules will be evaluated duri ng the “special monitoring evaluation”

conducted by the State as part of the periodic sanitary survey.

3 For more information on the AIP and the TCRDSAC, please go to

http://www.epa.gov/safewater/ disinfection/tcr/regulati on_revisions_tcrdsac.html

4 See Chapter 3.1 of this document.

5 Code of Federal Regulations

### DRAFT

Proposed Revised Total Coliform Rule 2-2 August 2010

Assessments and Corrective Actions Guidance Manual Element Proposed RTCR requirements

Routine Monitoring

§§ 141.853 to 141.858 • Total coliform samples must be collected at sites which are representative of water

quality throughout the distri bution system according to a written sample siting plan

subject to State review and revision.

• Samples must be collected at regular time intervals throughout the month except some

small systems may collect them on the same day.

• The number of monthly samples is based on population served. Reduced monitoring

is available for some small GW systems that meet certain criteria. See the section on

“Reduced Monitoring” in this table.

• Systems on less than monthly monitoring may be triggered to increase their

monitoring if certain conditions occur. Se e the sections on “Increased Monitoring

(NCWS)” and “Return to Routine Monitoring (CWS)” in this table.

• Each total coliform-positive routine sample must be tested for the presence of E. coli

and three repeat samples must be taken.

• Monitoring provisions are included for seasonal systems, 6 which require them to

monitor monthly, have a sample siting plan, and to demonstrate State-approved startup procedure. Reduced monitoring may be available for some small seasonal GW

systems that meet certain criteria. See th e section on “Reduced Monitoring” in this

table.

Reduced Monitoring

§§ 141.854, 141.855 • NCWSs serving 1,000 or fewer people (GW) – can be eligible to reduce their routine

monitoring of 1 sample per quarter (i.e., quarterly) to no less than 1 sample per year

(i.e., annual) if they meet the following criteria:

o Most recent sanitary survey shows that sy stem is free of sanitary defects, has a

protected water source, and meets approved construction standards;

o Clean compliance history 7 for a minimum of 12 months;

o An annual site visit by the State (or a Level 2 assessment by party approved by

State) within the last 12 months and corr ection of all identified sanitary defects.

System must have an annual site visit (o r its equivalent) every year thereafter to

remain on annual monitoring.

• Seasonal systems serving 1,000 or fewer people (GW) can be eligible for reduced

monitoring by having an approved sample site plan that designates the time period for

monitoring based on demand and vulnerability.

o For quarterly monitoring the seasonal system must also have a sanitary survey or

site visit or Level 2 assessment within last 12 months; a protected water source; a

clean compliance history for a minimum of 12 months, and be free of sanitary

defects.

o To reduce to 1 sample per year, the seasonal system must meet the criteria specified

above for quarterly monitori ng and have in place or adopt one or more additional

enhancements to barriers to contaminati on (cross connection control, certified

operator, meet disinfection criteria, maintenance of at least 4-log removal or

inactivation of viruses, other equivalent enhancements).

• CWSs serving 1,000 or fewer people (GW) – may reduce their routine monitoring (1

sample per month) to 1 sample per quarter if it meets the following criteria:

6 A seasonal system is defined as a non-comm unity water system that is operated in three or fewer calendar quarters per year.

7 A record of no maximum contaminant leve l (MCL) violations under 40 CFR 141.63; no monitoring violations under 40 CFR

141.21 or subpart Y; and no coliform treatment technique trigger exceedances or coliform treatment technique violations under

subpart Y.

### DRAFT

Proposed Revised Total Coliform Rule 2-3 August 2010

Assessments and Corrective Actions Guidance Manual Element Proposed RTCR requirements

o State certified operator;

o Most recent sanitary survey shows that syst em is free of sanitary defects (or has an

approved plan and schedule to correct th em), has a protected water source, and

meets approved construction standards;

o Clean compliance history for a minimum of 12 months;

o Meets at least one of the following criteri a: annual site visit by the State or a

voluntary Level 2 assessment by a party approved by the State and correction of all

identified sanitary defects (or an approve d plan schedule to correct them); cross

connection control; meet disinfection criteria; maintenance of at least 4-log removal

or inactivation of viruses; other equivalent enhancements to water systems as

approved by the State.

• No other systems are eligible for reduced monitoring.

Increased Monitoring

(NCWS)

§ 141.854 • NCWSs serving 1,000 or fewer people (GW), including seasonal systems, increase

from quarterly or annual monitoring to monthly monitoring if one of the following

occurs:

o Triggered Level 2 assessment or a 2 nd Level 1 assessment in 12 months;

o EC MCL violation;

o Coliform TT violation; or

o Two monitoring violations within 12 months if on quarterly monitoring or one

monitoring violation if on annual monitoring.

Return to Routine

Monitoring (CWS)

§ 141.855 • CWSs serving 1,000 or fewer people (GW) on quarterly monitoring return to monthly

monitoring based on same criteria above for NCWSs serving 1,000 or fewer people

(GW).

Return to Reduced

Monitoring (After

Being Triggered to

Increased Monitoring)

(NCWS)

§ 141.854 • NCWSs serving 1,000 or fewer people (GW) must meet the following criteria to return

to routine quarterly monitoring after being triggered to increased monitoring:

o Within the last 12 months, system must have completed a sanitary survey or a site

visit by the State or a voluntary Level 2 assessment by a party approved by the

State, must be free of sanitary defects, and must have a protected water source; and

o Clean compliance history 7 for a minimum of 12 months.

• NCWSs serving 1,000 or fewer people (GW) must meet the following criteria to return

to reduced annual monitoring in addition to meeting the criteria for returning to routine

quarterly monitoring:

o An annual site visit by the State or a voluntary Level 2 assessment and correction of

all identified sanitary defects; and

o Adoption of one or more additional enhancements to the water system barriers to

contamination (cross connection control, certified operator, meet disinfection

criteria, maintenance of at least 4-log re moval or inactivation of viruses, other

equivalent enhancements).

Return to Reduced

Monitoring (After

Being Triggered to

Return to Routine

Monitoring) (CWS)

§ 141.855 • CWSs serving 1,000 or fewer people (GW) must meet the same criteria for qualifying

for reduced quarterly monitoring. See section on “Reduced Monitoring” for CWSs

serving 1,000 or fewer people (GW) in this table.

### DRAFT

Proposed Revised Total Coliform Rule 2-4 August 2010

Assessments and Corrective Actions Guidance Manual Element Proposed RTCR requirements

Repeat Monitoring

§ 141.858 • All PWSs must take 3 repeat samples after a TC+ sample at locations specified in the

sample siting plan.

• For GW PWSs serving 1,000 people or fewer, a single sample can meet both the

triggered source water requirements of the GWR and the repeat sample requirements

of the proposed RTCR, but only if the Stat e approves the use of the single sample to

meet both rule requirements an d the use of EC as the fecal indicator. Otherwise, the

system must take an additional source sample to comply with the GWR.

Additional Routine

Monitoring

§§ 141.854, 141.855 • A PWS taking routine samples less than monthly is required to take a minimum of 3

routine samples the following month it serves water to the public after a TC+ sample,

unless the State waives the requirement.

Assessment

§ 141.859 • The PWS must conduct a Level 1 assessmen t if it exceeds any of the following

triggers:

o For systems taking ≥ 40 samples per month, the PWS exceeds 5.0% TC+ samples

for the month; or

o For systems taking < 40 samples per month, the PWS has ≥ 2 TC+ samples for the

month; or

o The PWS fails to take every required repeat sample after any single routine TC+

sample.

• The PWS must ensure that a Level 2 assessmen t is conducted either by the State or a

State -approved party (which could include a qualified PWS employee(s)) if it exceeds

any of the following triggers:

o The PWS has an E. coli MCL violation.

o The PWS has a second Level 1 trigger within a rolling 12-month period, or in 2

consecutive years for system s on annual monitoring.

• The system must complete the assessment as soon as practical after failure to take a

repeat sample or after notification of results (i.e., after it determines that an assessment

trigger has been exceeded).

• Assessment results and description of correc tive action(s) taken will be submitted to

the State within 30 days after determination of exceeding the trigger. The State must

determine if the assessment is sufficient, whether or not a sanitary defect is found.

Corrective Action

§ 141.859 • System must correct all sanitary defects found in the assessment.

• For corrections not completed by the time the assessment form is submitted, the

systems must be in compliance with a State-determined schedule and must notify the

State when completed.

Violations and Public

Notification (PN)

§§ 141.202, 141.203,

141.204, 141.860,

141.861 • EC MCL violation – when any of the following occurs; requires Tier 1 PN.

o EC+ repeat sample following a TC+ routine sample

o TC+ repeat sample following an EC+ routine sample

o Failure to take all required repeat samples following an EC+ routine sample

o Failure to test for EC when any repeat sample is TC+

• Coliform TT violation – occurs when a PW S fails to conduct required assessment

### DRAFT

Proposed Revised Total Coliform Rule 2-5 August 2010

Assessments and Corrective Actions Guidance Manual Element Proposed RTCR requirements

and/or corrective action; requires Tier 2 PN.

• Monitoring violation – occurs when PWS fa ils to take every required routine or

additional routine sample in a compliance period, or fails to analyze for EC following a

TC+ routine sample; requires Tier 3 PN.

• Reporting violation – occurs when a PWS fails to submit a monitoring report or

completed assessment form after a syst em properly conducts monitoring or

assessment; requires Tier 3 PN.

1

2

### DRAFT

Proposed Revised Total Coliform Rule 3-1 August 2010

Assessments and Corrective Actions Guidance Manual 

## 3. Assessments 1

2

3



### The purpose of performing assessments is to enhance public health protection by 4



### identifying the presence of "sanita ry defects” (defects that could provide a pathway of entry for 5



### microbial contamination into the distribution sy stem or that are indicative of a failure or 6



### imminent failure in a barrier that is already in place). Sampling results can trigger an assessment 7



### designed to take a closer look at the system and to identify wh ether one or more sanitary defects 8



### are present. This is a more proactive approach than that of the 1989 TCR and will lead to the 9



### identification and correction of problems that may compromise public health. 10

11



### The RTCR includes two levels of assessments – Level 1 and Level 2 (with the Level 2 12



### assessment being more detailed than a Level 1 a ssessment) – to recognize the severity of the 13



### situation and the varying level of effort required for the assessment. For example, a higher level 14



### of effort is needed to diagnose a problem arisi ng from situations of greater potential of public 15



### health concern such as repeat ed Level 1 triggers or an E. coli MCL violation. For either Level 1 16



### or Level 2 assessments, the PWS must assure the completion of the assessment as soon as 17



### practical after notification of their monitoring results. Having the PWS responsible for having 18



### the assessment conducted also serves to strengthen the PWS’s cap acity to ensure that barriers to 19



### contamination are in place and are effective in the future. The PWS will provide the primacy 20



### agency a completed Level 1 or Level 2 assessmen t form within 30 days after determination of 21



### exceeding the trigger. 22

23



### The minimum elements of both Level 1 and Level 2 assessments must include a review 24



### and identification of the following: 25

26



### 1. Inadequacies in sample sites, samp ling protocol, and sample processing 27



### 2. Atypical events that may have affected distributed water quality or indicate that 28



### distributed water quality was impaired 29



### 3. Changes in distribution system maintenance and operation that may have affected or 30



### are affecting distributed water quality including water storage 31



### 4. An evaluation of source water quality and tr eatment changes or conditions that may 32



### affect distributed water qu ality, where appropriate 33



### 5. Existing water quality monitoring data. 34

35



### Level 1 and Level 2 assessments consider the same five minimum el ements but the depth 36



### of consideration of those elements differ because of the differences in severity among the types 37



### of assessment triggers. Similarly, triggering a Le vel 2 assessment implies that a contamination 38



### event may be more complicated and pose a greate r risk; the level of skills and qualifications 39



### expected for a Level 2 assessor should be sufficien t to address the complexity and higher degree 40



### of risk. Chapters 3.2 and 3.3 describe the Level 1 and Level 2 assessments in greater detail and 41



### clarify the differences between th e two. Chapter 3.5 discusses the specific items in the example 42



### assessment forms found in Appendix A. States ma y also tailor specific assessment elements to 43



### the size and type of the system and PWSs in tu rn may tailor its assessment activities based on the 44



### specific characteristics of its distribution system. 45

46

### DRAFT

Proposed Revised Total Coliform Rule 3-2 August 2010

Assessments and Corrective Actions Guidance Manual 

### 3.1 Sanitary Defects 1



### As mentioned previously, sanita ry defects within the distri bution system are defined as 2



### defects that could provide a path way of entry for microbial cont amination into the distribution 3



### system or that are indicative of a failure or imminent failure in a ba rrier that is already in place. 4



### Proper operation and maintenance of the distributi on system is the last protective barrier to 5



### microbial contamination of drinking water. If the distribution system is breached, microbial 6



### contamination can enter the treated water and be transported to cu stomers, potentially resulting 7



### in adverse health outcomes. Therefore it is v ital to identify and correct sanitary defects to 8



### maintain distribution system integrity a nd proactively protect public health. 9



### Some examples of sanitary def ects are holes in tanks that co uld allow entry of insects or 10



### small animals, breaks in pipes that could allow en try of contaminated water (especially when low 11



### pressure events occur), and cr acks in well seals or casings. 12



### The goal of assessments is to provide a revi ew of the condition of the distribution system 13



### and source water components in order to identify if a sanitary defect exists that could have 14



### caused a coliform positive sample. When performing a Level 1 or 2 assessment, the PWS may 15



### find one or more sanitary defects. Ideally, th e PWS should determine if any of the sanitary 16



### defects is the likely cause of the coliform positive samples through an evaluation of data, 17



### additional sampling, and investig ation of system conditions. Documentation of the PWS 18



### findings should be submitted in accordance with the primacy agency requirements. It may or 19



### may not be possible to conclusively link the coli form positive samples to a given sanitary defect 20



### due to the complexity of dist ribution system configuration a nd transport of contaminants 21



### throughout the system. Even if the defect canno t be proven to be a likely cause of coliform 22



### positive samples, the PWS must corre ct all sanitary defects that are found to prevent them from 23



### providing a pathway to future contamination. The PWS should work with the primacy agency to 24



### develop a schedule for correction of sanitary de fects if it is not feasible to correct them 25



### immediately, which may be the case for corrective actions requiri ng major construction or capital 26



### improvements (e.g., replacement of a well, repairs to a storage facility). 27

28



### 3.2 Level 1 Assessments 29

30



### The Level 1 assessment consists of a relatively simple examination of the system’s 31



### source water, treatment, distribution system, a nd relevant operational practices. The Level 1 32



### assessment is intended as a self-assessment. EPA anticipates that this will be completed by the 33



### PWS and reviewed by the primacy agency. If the primacy agency determines that the 34



### assessment is insufficient, it wi ll consult with the PWS. 35

36



### A Level 1 assessment is triggered if samp ling results in any one of the following: 37

38



### 1. For systems collecting 40 or more samples per month, the PWS exceeds 5.0% total 39



### coliform-positive samples for the month; or 40



### 2. For systems collecting fewer than 40 samp les per month, the PWS has two or more 41



### total coliform-positive samples in the same month; or 42



### 3. The PWS fails to take every required repe at sample after any single routine total 43



### coliform-positive sample. 44

45

46

### DRAFT

Proposed Revised Total Coliform Rule 3-3 August 2010

Assessments and Corrective Actions Guidance Manual 

### For the Level 1 assessment, the PWS should l ook at conditions that could have occurred 1



### prior to the collection of the total coliform-positive sample(s). A Level 1 assessment can often 2



### be primarily completed using data on hand at the PWS and conducting limited inspections and 3



### does not necessarily include extensive new field i nvestigations. Interviews of appropriate PWS 4



### employees can also be a valuable means of obtaining important information. Example 5



### conditions that may result in coliform-positive sa mples include treatment process interruptions, 6



### loss of pressure, maintenance and operation activ ities, wet weather events, and recent operational 7



### changes. The PWS should also consider and not e the condition of system facilities, such as 8



### sample sites, distribution system, storage tanks, and source water. In addition, larger systems 9



### may want to target their assessments to specific sections of their distribu tion system or facilities 10



### if they find that the exceedances that triggered the assessment ar e clustered in one part of the 11



### system. 12

13



### PWSs must document their Level 1 assessment in an assessment form, which they must 14



### complete and submit to the primacy agency within 30 days after the PWS has determined that the 15



### trigger has been exceeded. For more discussion of the assessment forms, see Chapter 3.4 of this 16



### document. 17

18



### Identifying and correcting sanitary defects early will provide some assurance that the 19



### system has addressed the issue that may co mpromise public health. While the Level 1 20



### assessment is intended to be a relatively si mple assessment, it should be conducted thoroughly 21



### enough to capture the possibility that there may be multiple san itary defects. Systems should 22



### complete the entire assessment form, even if they believe they understand the apparent cause, to 23



### ensure they have a holistic picture of the overall integrity of their system and do not 24



### inadvertently overlook a sanitary defect. Ideally, a well-performed Level 1 assessment will 25



### prevent most systems from developing condi tions that lead to a Level 2 assessment. 26

27



### 3.3 Level 2 Assessments 28

29



### A Level 2 assessment is a more detailed examination of the system, its monitoring 30



### program and results, and its operational practices . The elements of a Level 2 assessment are the 31



### same as those of a Level 1 assessment, but each element is investigated in greater detail. A 32



### Level 2 assessment will likely include field investigations, additional sampling and additional 33



### inspections of facilities beyond thos e performed in a Level 1 assessment. The level of effort and 34



### resources required to implement the Level 2 asse ssments will be commensurate with a more 35



### comprehensive investigation, a higher level review of available information, and may involve the 36



### engagement of additional parties and expertis e. Table 3.1 presents examples of possible 37



### differences in the level of effort betw een a Level 1 and Level 2 assessment. 38

39

### DRAFT

Proposed Revised Total Coliform Rule 3-4 August 2010

Assessments and Corrective Actions Guidance Manual 

### Table 3.1 Examples of Possibl e Differences in Level of Ef fort between Level 1 and 1



### Level 2 Assessments 2

3

Level 1 Effort Level 2 Effort

• Review all monitoring results from appropriate

areas of the distribution system for the previous

12 months • Review all monitoring results from appropriate

areas of the distribution system for the previous

12 months

• Conduct additional investigatory monitoring

• Review cross connection control records for

medium- and high-risk facilities in the area of

the positive samples • Review cross connection control records for

medium- and high-risk facilities in the area of

the positive samples

• Inspect backflow prevention devices in the

medium- and high-risk facilities in the area of

the positive samples

• Review records of storage tank inspections • Review records of storage tank inspections

• Inspect storage tanks that feed the area of the

positive samples

• Review records of inspections of wells and

surface water source and weather events • Review records of inspections of wells and

surface water source and weather events

• Inspect wells and surface water sources

• Interview sample collectors, distribution system

managers, other appropriate employees • Interview sample collectors, distribution system

managers, other appropriate employees

• Consult with outside experts, professional

engineers

• Interview residents and businesses in the area of

the positive samples

• Review records of entry point and distribution

system disinfectant levels • Review records of entry point and distribution

system disinfectant levels, including historical

seasonal changes if any

• Conduct additional residual testing at the entry

point and appropriate locations in the

distribution system

• Review records of distribution system

maintenance, especially in the area of the

positive samples • Review records of distribution system

maintenance, especially in the area of the

positive samples

• Inspect on-going maintenance activities

• Notify the State of results and discuss with the

State as needed • Consult with the State about assessment plans

and approach, especially if the assessment is

triggered by detection of E. coli

.

• Notify the State of results and discuss with the

State

• Conduct on-site inspections as indicated by

record reviews and interviews above • Conduct on-site inspections as indicated

above

4



### If the primacy agency determines that the Level 2 assessment is insufficient, it will 5



### consult with the PWS. The primacy agency ma y also direct a PWS to perform an expedited 6



### action or additional actions in cases with significa nt potential for public health impact, such as in 7



### the case of an E. coli MCL violation. For example, the primacy agency may direct the PWS to 8

### DRAFT

Proposed Revised Total Coliform Rule 3-5 August 2010

Assessments and Corrective Actions Guidance Manual 

### apply temporary disinfection whil e the assessment is ongoing and before the cause and source of 1



### the contamination is determined. 2

3



### A Level 2 assessment is triggered if samp ling results in any one of the following: 4

5



### 1. The PWS has an E. coli MCL violation; or 6



### 2. The PWs triggers a second Level 1 asse ssment within a rolling 12-month period, 7



### unless the State has determined a likely cause for the situation that resulted in the 8



### initial Level 1 treatment technique trigger and establishes that the system has fully 9



### corrected the problem; or 10



### 3. For systems with approved reduced annual monitoring, a Level 1 treatment technique 11



### trigger in two consecutive years. 12

13



### Level 2 assessments are triggered by events that either (a) pose a potential immediate 14



### acute public health threat (i.e., trig ger associated with the presence of E. coli ) or (b) those that do 15



### not necessarily pose an immediate acute public health threat (i.e ., a second Level 1 trigger) but 16



### may still pose a potential serious health impact becau se of the persistence of the contamination. 17



### EPA anticipates that Level 2 assessments followi ng triggers associated with the presence of E. 18



### coli may be more involved than the Level 2 assessm ents following triggers in which there is no 19



### E. coli present, given the differing potenti al of public he alth concern. 20

21



### While the Level 1 assessment is intended as a self-assessment, Level 2 assessments must 22



### be conducted by a party approved by the primacy ag ency due to the higher level of complexity. 23



### The party conducting the assessment could be the primacy agency itself, a third party, or the 24



### PWS where the system has staff or management with the required certification or qualifications 25



### specified by the primacy agency. Chapter 3.7.2 of this document discusses Level 2 assessor 26



### qualifications in greater detail. 27

28



### In addition to the qualifications of the assessor, there are a number of other differences in 29



### how Level 2 assessments are conducted versus Leve l 1 assessments. In a Level 2 assessment, 30



### the conditions that could have occurred prior to the total coliform-positive sample(s), as well as 31



### the current condition of water sy stem facilities and system operation and maintenance, should be 32



### examined in detail, and the system should conduct a physical inspection of suspected facilities. 33



### During this examination, it is recommended that the assessor notes any atypical conditions, even 34



### if those conditions do not appear to definitively correlate with the total coliform- or E. coli35



### positive samples. The assessor should review past Level 1 assessments and sanitary survey 36



### results. The assessor should also consult with ot hers involved in operation or management of the 37



### system to gather additional observations and insi ght as to possible causes for the trigger. This 38



### consultation will also help to identify whether there are multiple causes for the trigger and/or 39



### sources of contamination. Gathering information on all elements will also be useful in setting a 40



### baseline if a PWS triggers another assessment in the future. This baseline information provides a 41



### good indication of where additional follow-up may be needed. 42

43



### As with a Level 1 assessment, PWSs must document their Level 2 assessment in an 44



### assessment form, which they must complete and submit to the primacy agency within 30 days 45



### after the PWS has determined that the trigger ha s been exceeded. For more discussion on the 46



### assessment forms, see Chapter 3.4 of this document. 47

48

### DRAFT

Proposed Revised Total Coliform Rule 3-6 August 2010

Assessments and Corrective Actions Guidance Manual 

### The Level 2 assessment should also be conduc ted thoroughly to capture the possibility 1



### that there may be multiple causes for the coliform positive. Level 2 assessments should be 2



### conducted as quickly as possi ble after notif ication of E. coli positive sample results. Assessors 3



### should complete the entire assessment form, even if they believe they understand the apparent 4



### cause, to ensure they have a holistic picture of the overall integrity of the system and do not 5



### inadvertently overlook a potential defect. 6

7



### 3.4 Assessment Forms 8

9



### As stated previously, PWSs must complete an assessment form (either for a Level 1 or 10



### Level 2 assessment) to document their assessment process and submit it to the primacy agency 11



### for review. Appendix A of this document cont ains an example of a Level 1 and a Level 2 12



### assessment form. These forms are intended as conceptual examples to describe practical 13



### expectations for the level of resources committe d to undertaking either a Level 1 or a Level 2 14



### assessment. Assessments conducted under the pr oposed RTCR should reflect the substance and 15



### effect of the elements of these example assessm ent checklists. However, primacy agencies may 16



### develop their own forms. Systems should contact their primacy agency to check whether to use 17



### the example forms presented in this documen t or a State- or system-specific form. 18

19



### The assessment forms for both Level 1 and Level 2 assessments in Appendix A are 20



### designed to cover the typical elements found with in a PWS. For each element, the assessment 21



### forms provide suggestions on items to evaluate th at are related to the pa thways and mechanisms 22



### for microbial contamination as outlined in Chap ter 1.4. Since an assessment is an examination 23



### of a particular PWS, it will th erefore have different component s for each system depending on 24



### the system’s source water, configuration, and the number and type of distribution system 25



### facilities present. The forms in Appendix A cannot cover all possible situ ations or distribution 26



### system configurations. Assessors should use pr ofessional judgment in the application of the 27



### forms to their system and provide additional info rmation to support conclusions, if warranted. 28

29



### The primacy agency makes the final determin ation on the adequacy and completeness of 30



### information provided in the assessment. PWSs should be familiar with the forms and required 31



### submittals so that they are prepared for an assessment in advance, should one be required. For 32



### example, PWSs may wish to crea te a standard operating proce dure (SOP) for what to do when 33



### coliform results trigger a Level 1 or Level 2 as sessment. When developing the SOP, systems 34



### should verify with their primacy agency whethe r there is a specific ve rsion of the assessment 35



### form that needs to be used, and understand which data source(s) they can use to fill out the 36



### various sections. 37

38



### In the completed assessment form, the PWS must identify the results of all elements of 39



### the assessment, any sanitary defects detected, corrective actions completed, and a timetable for 40



### any corrective actions not already completed. If no sanitary defects are found in an assessment, 41



### the assessor may note that no san itary defects were id entified. Upon completion and submission 42



### of the assessment form by the PWS, the primacy agency determines if the PWS has identified a 43



### likely cause for the Level 1 or Level 2 trigger an d establishes whether the system has corrected 44



### the problem. 45

46



### Appendix B provides examples of completed assessment forms. The major elements 47



### covered in the forms are discussed in Chapter 3.6 of this document. 48

49

### DRAFT

Proposed Revised Total Coliform Rule 3-7 August 2010

Assessments and Corrective Actions Guidance Manual 

### 3.5 Timeline for Assessments and Corrective Actions 1

2



### A PWS must complete a Level 1 or Level 2 assessment as soon as practical after the 3



### determination that a trigger has been exceeded. The completed assessment form must then be 4



### submitted to the primacy agency for review within 30 days after the PWS has determined that a 5



### trigger has been exceeded. The 30-day timefra me allows for sufficient time for problem 6



### identification and potential re mediation of the problem in conjunction with the follow-up 7



### assessment, in most cases. If the primacy agency determines that the assessment is insufficient 8



### (e.g., the conditions at the well were not fully assessed, or the storage tank was not fully 9



### inspected), the primacy agency must consult with the system. If necessary after consultation, the 10



### system must submit a revised assessment fo rm to the primacy ag ency on an agreed-upon 11



### schedule not to exceed 30 days from the date of the consultation. For corrections not completed 12



### by the time of submission of the assessment fo rm (e.g., in the case wher e parts need to be 13



### ordered and may take longer than 30 days to be delivered and installed), the system must 14



### complete the corrective action(s) in complian ce with a schedule determined by the primacy 15



### agency in consultation with the system. The sy stem must notify the primacy agency when each 16



### scheduled corrective action is completed. 17

18



### 3.6 Assessment Elements 19

20



### The minimum elements of both Level 1 and 2 assessments should include a review and 21



### identification of five key elements as outlined in the introduction to Chapter 3. Table 3.2 22



### demonstrates how the questions on the exampl e Level 1 and Level 2 assessment forms in 23



### Appendix A correspond to the five minimum elements required by the proposed RTCR. 24

25



### Table 3.2 Summary of Assessment Form Questions by Element 26

Element Questions on the

Assessment Forms that

Address the Element

Inadequacies in sample sites, sampling protocol, and sample

processing 3, 4

Atypical events that may have affected distributed water quality or

indicate that distributed water quality was impaired 1, 2

Changes in distribution system maintenance and operation that may

have affected or are affecting distributed water quality including water

storage 5, 6

An evaluation of source water quality and treatment changes or

conditions that may affect distributed water quality, where appropriate 7, 8, 9, 10

Existing water quality monitoring data 1, 2

27



### The following sections discuss the types of activities that a PWS may perform in 28



### completing a Level 1 or Level 2 assessment. 29

30



### 3.6.1 Operational Data Review (Questions 1 and 2) 31

32

### DRAFT

Proposed Revised Total Coliform Rule 3-8 August 2010

Assessments and Corrective Actions Guidance Manual 

### The operational data review includes collecti on, compilation, and analys is of system data 1



### from a variety of sources to get a more comple te understanding of system conditions and events 2



### that may have occurred prior to triggering an assessment. The data collected should include 3



### recent data as well as historical trends to provi de a basis for comparison to determine if atypical 4



### events have occurred. 5

6



### The operational data elements should be revi ewed by all systems, regardless of size or 7



### type. The available data and accessibility of elec tronic data may vary by system size and type. 8



### Large systems may have electronic databases from which to extract pertinent information 9



### including: 10

11



### • Distribution system and treatment plant pr ocess data from supervisory control and 12



### data acquisition (SCADA) systems for pumping, storage and pressure data 13



### • Water quality measurements from labor atory information management systems 14



### (LIMS) or external laboratory reporting systems 15



### • Customer complaint and water usage data fr om customer service information systems 16



### (CSIS) 17



### • Data on operations and repairs in the distribution system from maintenance 18



### management information systems (MMIS) 19



### • Recent and historical informati on from main break databases 20



### • Pipe material and condition information from asset management databases 21



### • Hydrant testing and fire fighting fr om fire department information 22



### • Activities performed from operations logs. 23

24



### For smaller systems, much of the data sources listed above may not be electronic and will 25



### therefore require additional effort on the system to put together and compile the data as part of 26



### the assessment. EPA therefore encourages these systems to ma intain records of the above 27



### mentioned data elements to help them conduct an assessment should they be triggered to do one. 28

29



### The operational data review will provide an indication of the elements of the assessment 30



### on which to focus efforts. For example, if the SCADA data indicates some low pressure 31



### readings in a particular area of the distribution system, follow-up investigations should focus on 32



### that area. However, other areas of the distri bution system should not be ignored as microbial 33



### contamination can be a result of multiple causes. 34

35



### A Level 1 assessment should include the coll ection and review of available data. 36



### Examples of these data include water quality (e .g., pH, turbidity, etc.) and pressure monitoring 37



### data. Tables and graphs summarizing the data and findings could be he lpful supplemental items 38



### to prepare and submit to the primacy agency, if asked to do so. A Level 2 assessment may 39



### include collection of additional data that is not readily available, a deeper examination of 40



### correlations between different data sources, hydraulic analysis, and additional sampling, 41



### interviews of employees, interviews of customer s in the affected areas, inspection of backflow 42



### prevention devices in suspect facilities, and more thorough inspection of faci lities and sources. 43



### For example, in the case where the presence of biofilms is the suspected cause of the positive 44



### coliform samples, more sophisticated genotypic char acterization techniques can be used to verify 45



### if a persistent biofilm microf lora is indeed the cause of the contamination. The Level 2 46



### assessment form (Appendix A) includes a series of questions about ope rational activities and 47



### results of data review to provide a basis for the detailed analysis. 48

### DRAFT

Proposed Revised Total Coliform Rule 3-9 August 2010

Assessments and Corrective Actions Guidance Manual 1



### Although the PWS is not required to submit the collected data and supplemental analysis 2



### with the assessment form, EPA recommends that th ese items be kept on file for future reference 3



### in case the PWS gets triggered to have an assess ment again. States may also want to look at 4



### these data and analysis during th eir review of the assessment forms or during a sanitary survey. 5

6



### Water Quality Data 7

8



### As part of any assessment, water quality data should be compiled. This data would 9



### include parameters collected in the distribution syst em and at the source or treatment plant. The 10



### parameters to be evaluated will vary by system type, treatment process used and other 11



### operational practices but may include the items ou tlined in Table 3.3. If systems do not currently 12



### collect water quality data at one of the locations suggested in Table 3.3, they should consider 13



### doing so in order to create a ba seline for comparison should anothe r assessment be triggered in 14



### the future. 15

16



### Table 3.3 Summary of Typical Water Qua lity Data to be Evaluated During an 17



### Assessment 18

Water Quality Parameter Loca tion of Sample Collection

Disinfectant residual concentration Throughout the distribution system

At storage tanks throughout the distribution

system

At the entrance to the distribution system at

each source

Total coliforms and E. coli All distribution system sampling sites,

including those for repeat and additional

samples

Entrance to the distribution system at each

source

Heterotrophic plate count All distribution system sampling sites for total

coliforms

Nitrite and nitrate (systems using chloramine) Distribution system sites with low disinfectant

residual

Treatment process performance parameters

(e.g. turbidity, pH) Throughout the treatment process

Entrance to the distribution system at each

source

19



### Once the water quality data have been collecte d, they should be analyz ed to determine if 20



### any atypical events have occurr ed. Depending on the data that are available, there may be 21



### several ways to examine the data. One good method is to develop a historical trend for 22



### monitoring results and individual parameters at each sampling location. Spreadsheet and 23



### graphing software can be helpful in developing a nd reviewing historic tr ends. The historical 24



### time series can be evaluated visually to determin e if there are differences between current results 25



### (under assessment) and historical trends. Figur e 3.1 provides an example of a historical time 26



### series graph of total chlorine measurements from distribution system samples using Microsoft 27



### Excel software. The average total chlorine concentration for each month is plotted for multiple 28



### years. This type of graph can help to identify if measured va lues are within normal ranges or 29

### DRAFT

Proposed Revised Total Coliform Rule 3-10 August 2010

Assessments and Corrective Actions Guidance Manual 

### might represent an atypical condi tion within the distri bution system. Simila r graphs could be 1



### constructed for minimum and maximum residual disinfectant measurements, total coliform 2



### positive samples, and related water quality sampling data. 3



### Figure 3.1: Example Time Series Graph fo r Distribution System Chlorine Results 4

5



### Additional samples could also be collected to further understand the contamination event. 6



### These samples could include follow-up total coliform samples as well as disinfectant residual 7



### measurements. 8

9



### Supplemental data sources beyond water quality measurements could also be considered 10



### in the assessment. For example, customer compla ints might show an increase in a particular area 11



### of the distribution system that could be correl ated to distribution syst em problems. Spatial 12



### analysis and mapping of complaints using geogra phic information system (GIS) software can be 13



### helpful in interpreting the data, as illustrated in Figure 3.2. In this example, majority of the 14



### complaints regarding the water’s color, tast e, and odor is occurring in areas where the 15



### disinfectant residual is 1.16 mg/L or less. 16

### DRAFT

Proposed Revised Total Coliform Rule 3-11 August 2010

Assessments and Corrective Actions Guidance Manual 1



### Figure 3.2: Example of Spatial Analysis of Disinfectant Re sidual and Customer Complaint 2



### Data 3

4

### DRAFT

Proposed Revised Total Coliform Rule 3-12 August 2010

Assessments and Corrective Actions Guidance Manual 

### Public health officials also track reported illnesses, doctor visits, and purchase of over1



### the-counter medicines. These public health da ta sources might be helpful in understanding the 2



### potential source and extent of contaminati on. Water systems should work to develop 3



### relationships with their local public health offi cials so that if an assessment needs to be 4



### conducted, health information can be more readily accessible. 5

6



### Operational Activities and Unusual Events 7

8



### Along with water quality measurements, it is important to unders tand the extent of 9



### activities occurring in the water system that may ha ve resulted in total coliform-positive samples. 10



### Compilation of operational activity data may requi re consultation with different departments 11



### within a water utility and with external agencies. The types of activities and events to be noted 12



### would include those that might result in distribution syst em contamination, including: 13

14



### • Main breaks and associated repairs 15



### • Events resulting in a loss of pressure (e.g., power failures) 16



### • Flushing and hydrant testing 17



### • Construction activity that impacts water mains 18



### • Unusually high (or low) demands that might alter typical flow patterns, including 19



### temporary connections for construction and fire fighting 20



### • Break-ins and vandalism at system facilities 21



### • Treatment process upsets 22



### • Weather events 23



### • Source water changes 24

25



### Once a list of distribution system activities and events has been compiled, this list can be 26



### compared to historical records to determine if any activities or events could have led to the 27



### distribution system contamination. Further investigation of any suspect operational activities or 28



### events should be conducted. 29

30



### Consideration of flow pathways or use of a hydraulic model can also be useful in 31



### determining if a specific activity could be rela ted to the coliform-positive samples at a given 32



### location. Figure 3.3 illust rates the output from a hydraulic m odeling analysis showing the areas 33



### of influence for different pump stations in the sy stem. Locations in this figure are color-coded to 34



### show the results of a source tracing analysis, wh ich tracks parcels of water from a selected 35



### location. Some locations receive water from more than one source as noted in the figure legend. 36



### This type of analysis can be us eful in finding the source of contam ination, particularly if several 37



### positive samples fall within the influence zone of a specific distribution system pump station or 38



### tank. In this instance, systems can focus their attention on specif ic locations at the distribution 39



### system in determining the cause of the positive samples. However, as mentioned previously, 40



### other areas of the distribution sy stem should not be ignored comple tely as the contamination can 41



### be a result of multiple causes. 42

43

### DRAFT

Proposed Revised Total Coliform Rule 3-13 August 2010

Assessments and Corrective Actions Guidance Manual 1



### Figure 3.3: Example of hydraulic modeling analysis to determine influence zones for pump 2



### stations 3

4



### 3.6.2 Sample Site and Protocol Ev aluation (Questions 3 and 4) 5

6



### This section of the assessment is designe d to determine whether water samples could 7



### have been contaminated during the sample collec tion or processing, resulting in total coliform8



### or E. coli- positive samples. In that case, the posi tive results may not indicate a distribution 9



### system problem but rather a sampling problem. Several references are available to provide 10



### detailed guidance on sampling (AWWA 2008; AP HA et al. 2005; USEPA 2001; USEPA 2006d; 11



### USEPA 2006e). EPA intends to review and re vise existing guidance and develop additional 12



### guidance on monitoring and sampling specific to the RTCR as needed. 13

14



### The evaluation of the sample site(s) w ith the positive sample(s) and the sampling 15



### protocol would be performed in a similar manner fo r systems of all sizes and types. Because the 16



### sample site(s) is/are a key indicator of whethe r the problem is system-wide or localized, the 17



### assessment would be similar for both a Level 1 and Level 2 assessment, and would include a 18



### field visit to inspect the sample location(s) or a detailed discussion with the sample collector to 19



### determine the conditions at the sample site(s). 20

21



### Some of the common items to evaluate at the sample site(s) include: 22

### DRAFT

Proposed Revised Total Coliform Rule 3-14 August 2010

Assessments and Corrective Actions Guidance Manual 1



### • Cleanliness and suitability of the sample tap and sink 2



### • Potential for hot water to enter the sample through the tap 3



### • Conditions that may have changed at the samp le site since the last sample collection 4

5



### In addition to sample tap contamination, it is possible that elements of the sampling 6



### protocol that were not followed closely could result in contaminati on of the sample. Elements of 7



### the sampling protocol may include: 8

9



### • Removal of the tap aerator 10



### • Adequate flushing of the tap prior to sample collection 11



### • Proper storage and preparati on of the sampling container 12



### • Correct storage, preservation, and hand ling of sample(s) during transport to 13



### laboratory 14



### • Compliance with holding time and temperature requirements 15

16



### Finally, this evaluation should in clude a discussion with the la boratory, either in-house or 17



### external, to determine if all laboratory quality ch ecks were performed with satisfactory results. 18

19



### 3.6.3 Water System Component Evalua tions (Questions 5 to 10) 20

21



### This section of the assessment addresses th e different components of a water system (e.g., 22



### the distribution system, storage fac ilities, etc.) to evaluate the potential for contamination at those 23



### areas. The extent to which a PWS should evaluate different co mponents depends on the system 24



### configuration and type. Smalle r systems would be expected to have fewer components and 25



### therefore a lesser level of effort in completing the water system component evaluations. Larger 26



### systems may focus their evaluation on areas of th e system which have been shown to be more 27



### greatly affected, particularly if their data re view confirms the exte nt of spread of the 28



### contamination. 29

30



### A Level 1 assessment for water system com ponents could primarily focus on available 31



### data that indicates the condition of the component at its last in spection date, observations from 32



### recent visits by operations staff, and other related data such as disinfectant residual that might 33



### assist in focusing the assessment efforts. This would include any previously noted sanitary 34



### defects or significant deficiencies, and record s on how these were addressed. An on-site 35



### inspection of components could be considered if it has been a year or more since the last 36



### inspection or sanitary survey. 37

38



### A Level 2 assessment would require a deta iled investigation of the components, 39



### particularly those near a cluster of positive samp le locations. This detailed investigation would 40



### require site visits and possibly hiring expert assistance for inspections, particularly for storage 41



### tanks that might require specialty equipment a nd confined space entry safety measures. The 42



### Level 2 assessment form (Appendix A) provides a lis t of questions that sh ould be answered as 43



### part of a Level 2 assessment. Th e questions in the form also provi de an indication of the level of 44



### detail that should be included for each component evaluation. 45

46



### For both a Level 1 and Level 2 assessment, the collection of additional samples for total 47



### coliforms with pot ential subsequent E. coli analysis and supporting wate r quality parameters is 48

### DRAFT

Proposed Revised Total Coliform Rule 3-15 August 2010

Assessments and Corrective Actions Guidance Manual 

### encouraged. Systems should keep records of a ny special purpose samples taken in order to 1



### create a baseline for comparison should another assessment be triggered in the future. 2

3



### Distribution System Components Evaluation 4

5



### From the operational data review, the PWS s hould have compiled data to indicate what 6



### activities had been occurring in the distri bution system, including operational changes, 7



### maintenance, and atypical events. Under the distribution system evaluation step of the 8



### assessment, further detail should be obtained for any event that mi ght be significant and 9



### additional data could be collected. The objective of this evaluation is to determine if a particular 10



### distribution system component ha s a sanitary defect that wo uld require correction, or if 11



### distribution system events could have cont ributed to the positive coliform samples. 12

13



### The initial focus of the distribution system ev aluation should be in the area closest to the 14



### positive coliform samples. Operator knowledge or the results of a flow path analysis or 15



### hydraulic model can be used to determine the area(s ) likely to be associated with a given sample 16



### site (see Figure 3.3). Once the immediate area ha s been examined, the evaluation can continue 17



### to areas of the distribution system fart her from the positive coliform samples. 18

19



### Distribution system facilities should be evaluated to determine that equipment is 20



### operational and in good repair. The evaluation should include elements such as the ones 21



### presented in Table 3.4. Depending on system configuration, not all elements would be present in 22



### all systems. 23

24



### Appendix B includes an example of an asse ssment where distribution system problems 25



### were found. The assessment of the distribution sy stem revealed an air release valve submerged 26



### in a flooded valve vault. To correct the probl em, a permanent sump pump was installed and 27



### portions of the system were shock chlorinated. 28

29

### DRAFT

Proposed Revised Total Coliform Rule 3-16 August 2010

Assessments and Corrective Actions Guidance Manual 

### Table 3.4 Summary of Items to Evalua te by Distribution System Component 1

Component Typical Items to Evaluate

Pump stations Proper operation of pumps and valves

Recent losses of power

Recent losses of pressure

Proper operation of surge control appurtenances

Distribution system pressure Maintenance of adequate pressure

Air-relief / Air-vacuum valves Proper operation of valves

Valve vault free of standing water and debris

Fire hydrants Proper operation of shut-off valves

Leaks at connection to lateral piping

Flushing assemblies / Blow-offs Proper operation of valves

Leaks at connection to piping

Pipes Recent main breaks

Recent leaks

Recent installation of new mains or construction activity

Distribution system isolation

valves Recent operation resulting in breakage

2

3

4



### Storage Facilities 5

6



### Storage facilities, or tanks, have been linked to microbial contamination events and 7



### therefore are an important component to assess when responding to positive coliform samples 8



### (Clark et al. 1996). Microbial co ntamination can enter storage fac ilities either through system 9



### water or external tank breaches. If contamin ation is introduced through system water (i.e., 10



### transported to the storage facility from a diffe rent contamination site), microbes can remain 11



### viable and possibly multiply within the tank water and sediments. Table 3.5 outlines some 12



### typical items to evaluate for st orage facilities. If warranted, a PWS should examine historical 13



### disinfectant residual data and collect additional samples. 14

15

### DRAFT

Proposed Revised Total Coliform Rule 3-17 August 2010

Assessments and Corrective Actions Guidance Manual 

### Table 3.5 Summary of Items to E valuate at Storage Facilities 1

Storage Tank Element Typical Items to Evaluate

Access hatches Signs of vandalism or forced entry

Ability of hatch to seal tightly when closed

Rust, holes, or other breaches

Vents Signs of vandalism or forced entry

Holes or other breaches in screens

Rust, holes or other breaches in vent piping and

penetration through tank wall

Overflow piping Rust, holes or other breaches in piping and

penetration through tank wall

Control valves Correct operation of level control valves, altitude

valves, and related appurtenances

Tank exterior Signs of deterioration, rust, or other breaches

Locations where ladders, railing, cell tower supports

and other attachments are made

Tank interior Integrity of lining material

Presence and extent of sediment within tank;

existence of microbes within sediment

Presence of dead animals

Disinfectant residual Level of disinfectant in tank, ideally at different

tank levels

2

3



### Treatment Processes 4

5



### For a PWS operating a treatment plant, includi ng those where a chlorinator at a well is 6



### the treatmentan assessment of the proper operati on of the treatment process is important to 7



### determine if a plant upset could be the source of the microbial contamination resulting in positive 8



### coliform samples. For most treatment facilities , regulatory data collected for compliance with 9



### related treatment requirements (e.g., Surface Wate r Treatment Rule, Ground Water Rule) should 10



### be available. A review of this data may indica te a potential treatment plant problem that could 11



### have allowed microbial contaminants to enter the distribution system. When reviewing the 12



### treatment data, particular atte ntion should be paid to disinf ection processes and turbidity 13



### removal, as these processes are responsible for th e majority of microbial inactivation (Letterman 14



### et al. 1999). For disinfection pr ocesses, the disinfectant feed sy stems and resulting disinfectant 15



### concentration should be evaluated to ensure that proper dosing has taken place and desired 16



### residuals are maintained. For turbidity rem oval, coagulation/sedimentation and filtration 17



### processes should be evaluated to ensure that mi crobial contaminants could not have entered the 18



### distribution system along with a spike in turbidit y. Power outages and othe r events that disrupt 19



### normal operations should also be considered. 20

21



### Appendix B includes an example of an a ssessment where a treatment system was 22



### determined to be the cause of positive coliform samples. In this case, pressure was lost during 23



### regular maintenance of a treatment system and the system may not have been properly 24



### disinfected prior to resuming service. 25

26

### DRAFT

Proposed Revised Total Coliform Rule 3-18 August 2010

Assessments and Corrective Actions Guidance Manual 

### Table 3.6 Summary of Treatme nt Elements to Evaluate 1

Treatment Element Typical Items to Evaluate

Equipment

(pumps, mixing units, settling

units, pipes, valves, chemical feed

units, filters) Equipment operational and maintained in

accordance with the treatment plant Operation and

Maintenance procedures

Recent installations or repairs

Treatment Process New sources

Recent changes in the treatment process

Interruptions in treatment – lapses in chemical feed

or proper mixing

Turbidity measurements at all appropriate locations

in the treatment process (source, settled water, preand post-filtration, finished water, etc.)

Disinfectant residual measurements and C x T

calculations

Flow rates at each plant process

2

3



### Wells 4

5



### For systems served by wells, the assessment s hould verify the integrity of the well and 6



### proper operation of the well system to ensure th at contamination could not have entered the 7



### distribution system from the wells. Particular attention should be paid to potential pathways that 8



### would allow the entrance of surface water, soil, an imals, or other foreign matter into the well. 9



### The well should also be constructed to preven t the accumulation of surface water around the well 10



### head and prevent inundation during periods of fl ooding or increased runoff. Table 3.6 outlines 11



### some typical items to evaluate for wells. So me elements may not be present depending on the 12



### design/configuration of the well and the type of pump in the well. 13

14

### DRAFT

Proposed Revised Total Coliform Rule 3-19 August 2010

Assessments and Corrective Actions Guidance Manual 

### Table 3.7 Summary of Item s to Evaluate at Wells 1

Well Element Typical Items to Evaluate

Well house / enclosure Signs of vandalism or forced entry

Well cap / Well seal Tightness of well cap or seal, presence of gaps or openings

Well vent Vent properly screened, self-draini ng, and has sufficient height

above ground

Well casing Holes, breaks, corrosion or deformation in casing and welds

Annular grout seal Missing, sunken, bridged, or channeled grout surrounding the well

casing

Pump and pump assembly Attached to casing with no unprotected openings and has watertight

seal

Pitless adaptor Integrity of pitless adaptor connection

Inundation Signs of inundation by floodwat er or runoff; depressions around

wellhead

2



### Appendix B provides an example of an assessment where well contamination was the 3



### likely cause of positive coliform samples. The well was found to have unsanitary conditions, 4



### possibly due to recent flo oding, and a corroded casing. 5

6



### Springs 7

8



### For systems served by springs, the assessment should verify the sanitary condition and 9



### proper operation of the spring and associated pi ping. The PWS should evaluate the condition of 10



### the spring development, impacts from surface water runoff and weather conditions, and the 11



### physical condition of the spring box. Impacts from vandalism or forced entry should also be 12



### evaluated to determine if holes or other breaches could have occurred that would allow for the 13



### introduction of microbial contaminants. Si gns of inundation should be checked, including 14



### deposits of soil or soil erosion. 15

16



### Appendix B includes an example of an assessment where a spring source was 17



### contaminated through a broken pipe. The pi pe was replaced to correct the defect. 18

19



### Surface Water Sources 20

21



### Surface water sources can be impacted by climatic events which can influence the 22



### influent water quality to a give n treatment process. Atypical ev ents may impede the ability of 23



### the treatment process to perform as desired and may allow for the introduction of microbial 24



### contaminants into the distribution system. H eavy rainfall and rapid snowmelt can carry large 25



### soil loads into surface water sources, thereby increasing turbidity and baseline microbial 26



### contaminant concentrations. Similarly, flooding can alter the raw water quality and require 27



### treatment changes to achieve good finished water quality. 28

29



### For systems with several surface water source s, a change from one source to another 30



### could trigger a treatment upset that might re sult in microbial contamination entering the 31



### distribution system. 32

33



### 3.7 Qualifications of Assessors 34

35

### DRAFT

Proposed Revised Total Coliform Rule 3-20 August 2010

Assessments and Corrective Actions Guidance Manual 

### 3.7.1 Level 1 Assessors 1

2



### A Level 1 assessment is a PWS self-assessment that should be conducted or managed by 3



### a responsible party of the PWS. This should be someone familiar enough with the system to 4



### answer the questions in the Level 1 assessment form or to gather correct information from others 5



### who work for the system. 6

7



### 3.7.2 Level 2 Assessors 8

9



### Ideally, a well-performed Level 1 assessm ent will prevent most systems developing 10



### conditions that will trigger them to conduct a Le vel 2 assessment. However when it does occur, 11



### a Level 2 assessment is triggered by a more signi ficant event; therefore a more comprehensive 12



### assessment is needed. The level of effort and resources committed to undertaking a Level 2 13



### assessment, relative to a Level 1 assessmen t, will be commensurate with the more 14



### comprehensive investigation and review of av ailable information, and the engagement of 15



### additional parties and expertise. A Level 2 assessment will likely include field investigations, 16



### sampling and additional inspections of fac ilities beyond those performed in a Level 1 17



### assessment. 18

19



### Level 2 assessments must be conducted by a pa rty approved by the State. Examples of 20



### such parties may include: 21

22



### • State or primacy agency personnel 23



### • An operator certified by the State to oper ate a system of similar size, type, and 24



### complexity 25



### • Circuit rider 26



### • A utility supervisor or manager supported by various utility experts 27



### • A consultant/consulting engineer 28

29



### For small non-community water systems: 30

31



### • Licensed plumber 32



### • Licensed well driller 33

34



### The State will determine its criteria and pr ocess for approval of Level 2 assessors and 35



### will determine which of the above parties are appropriate to conduct th e assessment given the 36



### complexity of the system and the policies of the State. If the PWS or a third party conducts the 37



### Level 2 assessment, the PWS or third party mu st follow the State requirements for conducting 38



### the Level 2 assessment. Systems should be aware of who may be appropriate assessors for their 39



### PWS so that if the Level 2 assessment is ev er triggered, the PWS does not lose time in 40



### identifying who will conduct this assessment. Wh en a Level 2 assessment is triggered, the PWS 41



### should resolve uncertainties about th e assessor by consulting with the State as soon as possible. 42

43



### Qualities of a Level 2 assessor may include: 44

45



### • An understanding of the objectives and structure of the RTCR 46



### • An understanding of the nature of the coliform group and E. coli , including its 47



### sources, control, and public health significance 48

### DRAFT

Proposed Revised Total Coliform Rule 3-21 August 2010

Assessments and Corrective Actions Guidance Manual 

### • A familiarity with bacteriological sampling practices 1



### • A working knowledge in how to interpret distribution system water quality data 2



### • A working knowledge in how to interpret di stribution system wa ter operational data 3



### • A working knowledge in how to in terpret source of supply data 4



### • An understanding of disinfection practices, a nd the potential implications of changes 5



### in disinfection practices 6



### • Familiarity with the system 7

8



### In general, the assessor needs “working know ledge” to oversee all elements covered by 9



### the Level 2 assessment. The depth of the understanding and knowledge required will depend on 10



### the complexity of the system being assessed. For example, a small system with only a well, 11



### storage tank and limited distribution system will requi re a different level of expertise than a large 12



### metropolitan water system. While both have operational data, in one case the assessor may be 13



### interpreting information manually recorded from a pressure gauge while in the other case the 14



### assessor may need a working familiarity with SCADA. 15

16



### It is important to recognize that in some cases, one individual may not have all the 17



### expertise and a team approach may be needed. It is also worth noting that utilities may gain 18



### value from having someone outside their system pr ovide a “fresh set of eyes”. The State may 19



### wish to consider allowing certified operators wi th the appropriate qualifi cations to conduct Level 20



### 2 assessments at other systems. 21

22



### 3.8 Assessments and Sanitary Surveys 23

24



### The performance of sanitary surveys and a ssessments (when triggered to do so) are 25



### important tools in protecting the quality of drinking water. Sa nitary survey requirements for 26



### surface and ground water systems have been established for all system sizes and types under the 27



### Interim Enhanced Surface Water Treatment Rule (IESWTR) (USEPA 1998a) (40 CFR 28



### 142.16(b)(3)), and the Ground Water Rule (GWR ) (USEPA 2006b) (40 CFR 142.16(o)(2)(i)). 29



### Hence, the proposed RTCR does not include new pe rformance requirements for sanitary surveys 30



### (e.g., how and when to conduct sanitary surveys). However, the results of a sanitary survey can 31



### impact a system’s monitoring frequency under the proposed RTCR (see additional discussion in 32



### “ What are the overlaps between sanitary su rveys and a Level 1 or Level 2 assessment?” in this 33



### section). 34

35



### This section is not intended to represent guidance on the performance or requirements of 36



### conducting sanitary surveys. Othe r resources are available for th at purpose. Sanitary survey 37



### resources, such as a prep course, learner’s gui de, and inspector’s field guide can be found on line 38



### at http://www.epa.gov/safewat er/dwa/sanitarysurvey/ . This section discu sses basic differences 39



### between sanitary surveys and Level 1 and Level 2 assessments . Specifically, this section 40



### addresses what a sanitary survey is, how often it is performed, the objective of a sanitary survey, 41



### and who does them relative to Level 1 and Level 2 assessments. 42

43



### What is a sanitary survey ? 44

45



### A sanitary survey is a comprehensive on-site evaluation of all water system components 46



### and operations and maintenance procedures. Specif ically, a sanitary survey is defined in 40 CFR 47



### 141.2 as an “onsite review of the water source (identifying sources of contamination using 48

### DRAFT

Proposed Revised Total Coliform Rule 3-22 August 2010

Assessments and Corrective Actions Guidance Manual 

### results of source water assessments where av ailable), facilities, equipment, operation, 1



### maintenance, and monitoring compliance of a public water system to evaluate the adequacy of 2



### the system, its sources and operations and the distribution of safe drinking water.” The 3



### requirements specify eight elements that must be included in a sanitary survey: (1) source; (2) 4



### treatment; (3) distribution system; (4) finished water storage; (5) pumps, pump facilities, and 5



### controls; (6) monitoring and re porting and data verification; (7) system management and 6



### operation; and (8) operator compliance with State requirements. The performance of 7



### comprehensive and periodic sanitary surveys is important in the identific ation and correction of 8



### significant deficiencies to ensure the long-term safety of dri nking water supplies. Sanitary 9



### surveys are important tools for identifying poten tial vulnerabilities to fecal contamination. 10

11



### What are the differences between a sanitary survey and a Level 1 or Level 2 assessment? 12

13



### Scope 14

15



### A sanitary survey is much broader in scope th an either a Level 1 or Level 2 assessment. 16



### Although a sanitary survey incl udes elements that are sim ilar as in an assessment (e.g., 17



### evaluation of the source water, th e distribution system, storage facilities, et c.), it covers other 18



### elements such as system management and operation, and operator compliance with State 19



### requirements that are beyond what an assessment re quires. The Level 1 and Level 2 assessments 20



### are specific to only those elements related to san itary defects that provide pathways of entry for 21



### microbial contamination or those th at are indicative of a failure or imminent failure in a barrier 22



### that is already in place. More information regarding the specific elements of Level 1 and Level 2 23



### assessments can be found in Chapter 3.5 of this document. 24

25



### Frequency 26

27



### Sanitary surveys are performed periodically an d routinely on a schedule. The State must 28



### complete sanitary surveys for all surface water systems (including ground water under the direct 29



### influence of surface water) no le ss frequently than every thr ee years for community water 30



### systems and no less frequently than every five years for non-community systems. Ground water 31



### community water systems must have sanitary surv eys no less than every three years, with the 32



### possibility of having the frequenc y reduced to no less than every fi ve years if the system has an 33



### outstanding performance. Non-community gr ound water systems ( both non-transient and 34



### transient non-community) are required to have sa nitary surveys no less than every five years. 35



### Level 1 and Level 2 assessments on the other ha nd are performed in response to treatment 36



### techniques triggers so they are not on a routine schedule. Specific trigge rs for Level 1 and Level 37



### 2 assessments are found in Chapters 3.2 a nd 3.3 of this document, respectively. 38

39



### Who conducts them? 40

41



### Sanitary surveys must be conducted by the St ate or an agent approved by the State or 42



### primacy agency. A Level 1 assessment as i ndicated in Chapter 3.2 is a self-assessment 43



### completed by the qualified PWS staff and reviewed by the State or primacy agency. A Level 2 44



### assessment is conducted by a party approved by the St ate. It could be co nducted by the State or 45



### primacy agency, an approved third party, or qual ified PWS staff or management who meet the 46



### certifications or qualifications specified by the State or primacy agency. Chapter 3.7 of this 47



### document discusses specific qualifications of assessors. 48

49

### DRAFT

Proposed Revised Total Coliform Rule 3-23 August 2010

Assessments and Corrective Actions Guidance Manual



### What are the overlaps between sanitary su rveys and a Level 1 or Level 2 assessment? 1



### Sanitary survey outcomes can impact m onitoring requirements under the proposed 2



### RTCR. For example, the proposed RTCR allows all systems to transition to the new rule at their 3



### current TCR monitoring frequency, including sy stems on reduced monitoring under the current 4



### TCR, provided they meet certain criteria. Fo r systems serving 1,000 or fewer people, monitoring 5



### frequency will be evaluated during each sanitary survey conducted after the compliance effective 6



### date of the RTCR. The proposed RTCR does not change existing sanitary survey requirements 7



### under the IESWTR and the GWR except to add th e special monitoring evaluation that States 8



### must conduct at systems serving 1,000 or fewer pe ople. The purpose of th ese special monitoring 9



### evaluations is to ensure that the distribution sy stem is evaluated in sufficient detail. These 10



### special monitoring evaluations are not anticipa ted to significantly in crease the burden of 11



### conducting sanitary surveys because the systems (serving 1,000 or fewer people) are relatively 12



### simple, and the evaluation is performed during the routinely scheduled sanitary survey. 13

14



### For years in which the State pe rforms a sanitary survey of a NCWS (at least every five 15



### years for NCWSs), a sanitary survey performed duri ng the same year can also be used to satisfy 16



### the annual site visit requirement for systems wanting to qualify for annual monitoring. Also, in 17



### some instances, the performance of an assessmen t (especially a Level 2 assessment) may overlap 18



### with a scheduled sanitary survey. To the extent that the requirements to perform an assessment 19



### may be satisfied as part of the sanitary surv ey, PWSs and States may realize a cost savings 20



### compared to performing a separate assessment. It must be kept in mind though, that the 21



### assessment must be conducted within the requir ed timeframe and not be delayed to when the 22



### sanitary survey is scheduled to be performed. Also, the person doing the assessment would have 23



### to be qualified to conduct a sanitary survey and the investigation would have to meet the 24



### minimum criteria of both the assessment as well as the sanitary survey. 25

26



### Sanitary defects that are identified during an assessment may or may not be considered to 27



### be a significant deficiency according to the gu idelines set by the primacy agency. The PWS 28



### should coordinate with their primacy agency re garding whether the Level 2 assessment can be 29



### considered part of a required sanitary survey. 30

### DRAFT

Proposed Revised Total Coliform Rule 4-1 August 2010

Assessments and Corrective Actions Guidance Manual 

## 4. Corrective Actions 1

2

3



### This chapter discusses the corrective action requirement s of the proposed RTCR and 4



### various examples of corrective actions that can help mitigate or eliminate sources of coliform 5



### contamination that may occur during operation a nd maintenance of a treatment process or a 6



### water system. Table 4.2 provides a summary of t hose corrective actions, and the purpose or type 7



### of water quality problem addressed by each action. 8

9



### As mentioned in Chapter 2, the three main obj ectives of the proposed RTCR are: (1) to 10



### evaluate the effectiveness of tr eatment, (2) to determine the inte grity of the distribution system, 11



### and (3) to signal the possible presence of f ecal contamination. While a number of other 12



### regulations also focus on treatment (such as th e suite of Surface Water Treatment Rules or the 13



### Ground Water Rule), the proposed RTCR builds on th e barriers established at the source and 14



### treatment plants and seeks to maintain a suffi cient barrier in the distribution system. The 15



### corrective actions described in this chapter repres ent key actions for maintaining or restoring the 16



### integrity of the distribution system barrier. Th is multiple barrier approach is essential to 17



### protecting public health and systems may find that the corrective actions listed in this chapter 18



### may improve their compliance for a number of regulations, not just the proposed RTCR. The 19



### interrelated nature of regulations can also be a challenge as adjustments to improve compliance 20



### for one rule may inadvertently affect a system’s ab ility to comply with another rule. Issues such 21



### as these can be managed with careful consider ation and are addressed in Chapter 4.4 of this 22



### document. 23

24



### 4.1 Common Causes 25

26



### An overview of general cause s of total coliforms and E. coli in the distribution system 27



### was presented in Chapter 1.4. Discussions a nd informal surveys with States and PWSs 8 

### have 28



### identified the following as some of th e common causes of total coliforms and E. coli detections 29



### in the distribution system, a number of which are interrelated: 30

31



### • Failure to disinfect (or improper disinf ection) after maintenance work on the 32



### distribution system 33



### • Main breaks, especially in certain vulnerabl e locations such as under a stream or high 34



### groundwater level 35



### • Holes in storage tank, inadequate screeni ng, etc. which could allow animals and/or 36



### fecal matter to enter the tank 37



### • Loss of system pressure (sometimes associated with main breaks or loss of power) 38



### • Lack of regular flushing programs 39



### • Biofilm build-up in the distribution system, including biofilms at multiple locations or 40



### that move throughout system, or those associ ated with seasonal changes and/or loss 41



### of disinfectant residual 42

8 Informal surveys of their constituents were conducted from February to March 2010 by the American Water

Works Association (AWWA), the Association of Metropo litan Water Agencies (AMWA), and the Association of

State Drinking Water Agencies (ASDWA) to determin e the common causes of coliform-positive results in the

distribution system and the types of corrective actions taken in response to those positive results.

### DRAFT

Proposed Revised Total Coliform Rule 4-2 August 2010

Assessments and Corrective Actions Guidance Manual 

### • Cross connections, especially at certain high-risk locations (e.g., hospitals, chemical 1



### plants, chemical holding/storage facilities, funeral homes, etc.) 2



### • Inadequate disinfectant residuals 3



### • Contaminated sampling taps 4



### • Sampling protocol errors. 5

6



### The specific cause(s) of total coliforms and E. coli in the distribution system will differ 7



### from system to system. The Level 1 and Le vel 2 assessments discussed in Chapter 3 are 8



### designed to help identify the specific causes so they can be appr opriately addressed. 9

10



### 4.2 Common Corrective Actions 11

12



### The type of corrective action performed will depend on the identified cause. Some 13



### actions can be performed in response to multiple types of causes, and multiple actions may be 14



### needed in response to a single identified cau se. Table 4.1 describes some common general 15



### actions that would be taken in response to th e common causes listed in Ch apter 4.1. Each of the 16



### corrective actions listed in Table 4.1 are described in more detail in the following sections, along 17



### with examples that can help mitigate or elimin ate the sources of coliform contamination. Table 18



### 4.2 summarizes these actions along with the general purpose for taking such actions. 19

20



### Corrective actions should be completed in accordance with State guidance and industry 21



### best practices. States often have guidance for operation and maintenance of the water system, 22



### and for emergency response planning and implem entation of cross connection control programs. 23



### Systems should be aware of State guidelines fo r investigation, operati on and maintenance, and 24



### corrective action, and consult with the State as n ecessary to complete corr ective actions that the 25



### State will consider to be sufficient. An example of State guidance is the Recommended 26



### Standards for Water Works (also known as the 10 States St andards) (Great Lakes et al. 2007). 27

28



### Appendix C of this document presents additional information on the common causes of 29



### coliform detection in the distri bution system, possible corrective actions which systems can take 30



### to correct the problem, and a dditional sources of informati on for correcting the problem. 31

32



### Drinking water system components that are used to implement correction actions to 33



### distribution system problems should be in comp liance with NSF/ANSI Standard 61. NSF/ANSI 34



### Standard 61 addresses drinking water system co mponents that are in c ontact with finished 35



### drinking water and whether contaminants leach or migrate from the product/material into the 36



### drinking water at levels that are above acceptable levels in finished waters. 37

38



### In addition, Appendix D contains a listing of AWWA Standards that are typically 39



### minimum best practices and help to ensure that a product (e.g., pipes, fittings, meters, etc.) or a 40



### process (e.g., main flushing, main installation, etc.) described in a standard will provide 41



### satisfactory service. These standards can be valuable resources in implementing corrective 42



### actions. 43

### DRAFT

Proposed Revised Total Coliform Rule 4-3 August 2010

Assessments and Corrective Actions Guidance Manual 

### Table 4.1: Common Causes and Asso ciated Common Corrective Actions 1

Common Cause Common Corrective Action(s)

Failure to disinfect (or improper disinfection)

after maintenance work in the distribution

system Disinfection

Main breaks Disinfection

Replacement/Repair of Distribution System Components

Holes in storage tank, inadequate screening,

etc. Replacement/Repair of Distribution System Components

Maintenance of Storage Facility

Addition of Security Measures

Development and Implementati on of an Operations Plan

Loss of system pressure Maintenance of Adequate Pressure

Addition or Upgrade of On-line Monitoring and Control

Biofilm accumulation in the distribution

system Flushing

Maintenance of Adequate Pressure

Cross connections Maintenance of Adequate Pressure

Implementation or Upgrade of a Cross Connection

Control and Backflow Prevention Program

Inadequate disinfectant residuals Disinfection

Flushing

Maintenance of Appropriate Hydraulic Residence Time

Addition or Upgrade of On-line Monitoring and Control

Contaminated sampling taps Replacement/Repair of Distribution System Components

Sampler Training

Sampling protocol errors Sampler Training

Development and Implementati on of an Operations Plan

2

3

### DRAFT

Proposed Revised Total Coliform Rule 4-4 August 2010

Assessments and Corrective Actions Guidance Manual 1



### Table 4.2 Summary of Corrective Actions 2

Action Purpose

Disinfection (Chapter 4.2.1) Improve or maintain disinfectant residual in the distribution

system.

Flushing (Chapter 4.2.2) Keep system clean and free of sediment.

Reduce disinfectant demand of pipe surfaces.

Remove stagnant, untreated, or contaminated water.

Address water quality deterioration at dead-ends.

Replacement / Repair of Distribution System

Components (Chapter 4.2.3)

Valves

Water Mains

Fittings

Hydrants

Meters

Dedicated Sample Taps Reduce potential sources / pathways of contamination from

improper installation or material degradation.

Maintenance of Adequate Pressure (Chapter 4.2.4)

Booster Pumping Stations

Pump Modifications or Replacement

Variable Frequency Drive

Elevated Storage Facilities

Surge Relief Valves

Surge Tanks Minimize sudden changes in water velocity which impact

system pressure.

Reduce risk of backflow and intrusion contamination resulting

from low pressures.

Reduce risk of hydraulic disturbances to pipe surface biofilm.

Maintenance of Appropriate Hydraulic Residence

Time (Chapter 4.2.5)

Looping Dead-Ends

Installing Appropriate Main Sizes

Automated Flushing Devices

Storage Facility Modifications Mitigate water quality problems associated with increased water

age (e.g., higher DBP formation, reduced disinfectant residual,

increased microbial activity, nitr ification, and taste-and-odor

problems).

Maintenance of Storage Facility (Chapter 4.2.6)

Inspecting / Cleaning of Tanks

Lining of Storage Tanks

Vent / Hatch Repair

Tank Repair Remove contamination from birds and insects.

Remove accumulated sediment.

Protect against tank wall corrosion.

Prevent entry of vectors (e.g., birds, etc.)

Implementation or Upgrade of a Cross Connection

Control and Backflow Prevention Program

(Chapter 4.2.7) Prevent flow of non-potable substances into the distribution

system.

Sampler Training (Chapter 4.2.8) Reinforces proper sampling and sample handling procedures to

obtain uncontaminated samples.

Reduces errors in sampling results.

Addition or Upgrade of On-line Monitoring and

Control (Chapter 4.2.9)

Water Quality Monitoring & Control

Pressure Monitoring & Control Automatically control and monitor disinfectant dosages and

water quality parameters (other than total coliforms).

Monitor pressure levels to identify physical problems in the

system (e.g., pipe breaks, leaking valves, etc.).

Addition of Security Measures (Chapter 4.2.10) Monitor potential locations for vandalism or security breaches

that could lead to water contamination.

Increase public confidence in protection of their drinking water.

Development and Implementation of an Operations

Plan (Chapter 4.2.11)

Develop Standard Operating Procedures (SOPs)

Develop a Sampling Plan

Perform Routine Inspections

Develop an Emergency Response Plan

Ensure the availability of appropriately qualified

operators Integrate all operations and maintenance functions to meet flow,

pressure, and water quality goals.

Establish a routine distribution system sampling plan.

Implement an inspection and maintenance program to reduce

sanitary defects.

Define an emergency response plan for the distribution system

to reduce reaction time and minimize confusion in emergencies.

Ensure around-the-clock responsiveness.

### DRAFT

Proposed Revised Total Coliform Rule 4-5 August 2010

Assessments and Corrective Actions Guidance Manual 1

2



### 4.2.1 Disinfection 3

4



### Many systems use disinfection (by applyi ng either temporary disinfection, shock 5



### chlorination, or booster disinfecti on) as a response to positive coliform results. It is also 6



### commonly used as a precautionary measure, especially when th e cause of a positive coliform 7



### sample has not been identified, to help mitigate any potential contamination that could be present 8



### in the system. If a system is found to have co ntamination that requires a long term solution, it 9



### may take time for the system to design and inst all a corrective action. In the meantime, the 10



### system cannot serve the contaminated water to it s customers. The primacy agency may require 11



### the system, as part of its corrective action, to apply chlorination until the contamination is 12



### eliminated or a corrective action is put in place. When temporary chlorination is applied in 13



### response to a coliform occurrence, the system s hould notify the State Chlorination should be 14



### kept in place until the State has reviewed the situation and has determined if the contamination 15



### has been addressed and the tempor ary disinfection can be suspende d or if the disinfection needs 16



### to be continued. 17

18



### Temporary disinfection can be conducted at th e point of entry to th e distribution system 19



### or can be installed at a location in the distribution system to targ et a specific area. Depending on 20



### the extent of the problem revealed by the Level 1 or Level 2 assessment, system-wide or targeted 21



### disinfection (such as shock chlorination) ma y be an appropriate corrective action. 22

23



### For non-disinfecting systems or those us ing free chlorine, temporary/additional 24



### disinfectant in the form of sodium hypochlorite (bleach) is of ten used because it is easier to 25



### install and operate than gaseous chlorination or other disinfection met hods, particularly on a 26



### temporary basis. It is a low cost option that can provide some prot ection to a portion of a 27



### distribution system or across an entire pipe ne twork. However, care should be used in the 28



### storage of hypochlorite as age and temperature have been show n to be associated with the 29



### conversion of hypochlorite to perc hlorate (Stanford et al. 2009). 30

31



### It is important to note that temporary disinfect ion is better suited to deal with a single 32



### event and is not intended to deal with a ch ronic problem like source water contamination. 33



### Systems using chloramine as a secondary disinf ectant should carefully ba lance chlorine addition 34



### with ammonia to maintain the desired chlori ne to ammonia ratio for optimal chloramine 35



### formation. 36

37



### Booster disinfection facilitie s located throughout a distri bution system can provide 38



### additional chemical treatment in the system. Booster disinfection can improve or maintain 39



### disinfectant residual levels in a distribution system. Prior to discharge into the distribution 40



### system, potable water from a treatment facility mu st have a certain disinf ectant residual level to 41



### minimize microbial growth. These levels are defined by State and Federal government 42



### regulations. Organics and reduced metals in the water also consume disinfectant residuals; 43



### therefore, it is vital to maintain an appropriate di sinfectant residual level in the system in order to 44



### avoid increased levels of total coliforms in the system. 45

46



### See Chapter 4.4 of this document for a disc ussion of simultaneous compliance issues 47



### systems should consider when using di sinfection as a co rrective action. 48

49

### DRAFT

Proposed Revised Total Coliform Rule 4-6 August 2010

Assessments and Corrective Actions Guidance Manual 

### 4.2.2 Flushing 1

2



### A water main flushing program helps to keep the system clean and free of sediment, can 3



### reduce the disinfectant demand of pipe surfaces, and removes stagnant water and untreated or 4



### contaminated water that may have entered the system (Kirmeyer and Friedman 2000). Flushing 5



### can also be used to address water quality de terioration at dead-ends. The volume of water 6



### flushed is related to the length of flushing time and flow rate from the hydrant. Water systems 7



### should flush until a disinfectant residual can be m easured or some other water quality target is 8



### reached (other than just until the water appear s clear). A system could perform scheduled 9



### system-wide flushing, and/or periodic unscheduled (or “spot”) flushing which can be used to 10



### address isolated water quality problems, includi ng total coliform-positive samples. However, 11



### spot flushing should not be used as the only so lution to positive coliform results or low residual 12



### events. Flushing should be used until the system identifies the source of the problem and a more 13



### permanent fix. 14

15



### Upon obtaining a positive coliform sample, a co mmon response is to flush the area near 16



### the sample site to draw in fresh water and remove any contaminated water that may be present. 17



### This unscheduled spot flushing is different from a routine flushing program in that the flushing 18



### only occurs when triggered by a water quality m easurement, customer complaint, or similar 19



### event. 20

21



### Minimum elements of a flushing scheduled/r outine program are outlined in the AWWA 22



### G200 Standard (AWWA 2004) and include: (1) a prev entive approach to a ddress local problems 23



### or customer concerns and routine flushing to avoid water quality problems; (2) use of an 24



### appropriate flushing velocity to address water quality concerns; a nd (3) written procedures for all 25



### elements of the flushing program including wate r quality monitoring, regu latory requirements 26



### and specific flushing procedures. 27

28



### 4.2.3 Replacement / Repair of Dist ribution System Components 29

30



### Distribution system component s and appurtenances such as valves, pipes, fittings, 31



### hydrants, meters, and sample taps are integral pa rts of a water system. These components are 32



### also potential sources of contamin ation if improper installation or material degradation allows 33



### leaks or other entry points for contaminati on into a distribution sy stem. Inspection of 34



### components may indicate that they should be replaced or repaired as part of proper maintenance, 35



### whether or not it is identified as the cause of the leak or as a possible entry point for 36



### contamination. Some components throughout the di stribution system are located below grade, 37



### making a leak difficult to locate. However, a nu mber of technologies have been developed to 38



### locate leaks below grade. Any repairs or re placements should be completed with proper 39



### attention to prevent contaminati on of the distribution system. See the AWWA standards listed in 40



### Chapter 4.5 of this document for more informa tion on installation, repair , and replacement of 41



### distribution system components. 42

43



### Valves 44

45



### Valves are located throughout a distribution sy stem to isolate portions of the system as 46



### needed. Leaks at the connection points between the valve and the adjacent pipe, as well as a 47



### valve seat or valve body, can create a pathway for contamination. 48

49

### DRAFT

Proposed Revised Total Coliform Rule 4-7 August 2010

Assessments and Corrective Actions Guidance Manual 

### Water Mains 1

2



### The condition of distribution system piping can be vital to the quality of water being 3



### conveyed to a community. Contaminants may enter through holes, breaks, cracks or joints in the 4



### piping. The condition of a pipe can vary base d on type, age, and location of the pipe. 5



### Depending on the condition of the pipe, the water main can be replaced or repaired to stop 6



### infiltration into the system. 7

8



### Fittings 9

10



### There are many types of fitti ngs located throughout a distribution system. The most 11



### common type of distribution system fitting is a cross. A cross has four connections which make 12



### it more susceptible to leaks. Leaks can occur because of a crack on the fitting or through the 13



### gasket between the fitting and another a ppurtenance, e.g., a valve, cap, or pipe. 14

15



### Hydrants 16

17



### Hydrants are located throughout a distribution system to provide potable water at 18



### required fire flow pressures for emergency situ ations. Hydrant connections are tapped off the 19



### distribution system; therefore, these connect ions can be possible locations for coliform 20



### contamination to enter a distribution system. Replacing a damaged or faulty fire hydrant can 21



### help eliminate sources of contamination into th e distribution system as it eliminates a pathway 22



### for contamination. Systems should attempt to cont rol usage of the hydrants as much as possible 23



### to eliminate unauthorized usa and install b ackflow prevention devices where possible. 24

25



### Meters 26

27



### Meters are located at entry poi nts to commercial, residential, and industrial facilities to 28



### measure the amount of water that is consumed at a particular location. Sizes for each of the 29



### meters will vary based on the type and usage re quirements of a facility. Contamination may 30



### enter through the connection points of the meter and the distribution system. Replacing a broken 31



### or faulty meter can help prevent contamination of the distribution system through leaks, as it 32



### eliminates a pathway for contamination. 33

34



### Dedicated Sample Taps 35

36



### Typical sample locations often include bot h customer taps and dedicated sampling 37



### stations. A dedicated sampling st ation is a device that is plum bed directly into a distribution 38



### system line to provide “improved access to the distribution system water and provide 39



### reproducible samples that are representative of wa ter quality at the customer’s meter” (Kirmeyer 40



### and Friedman 2000). Installing dedicated sample taps can therefore minimize the occurrence of 41



### contamination that can result from improper sa mpling practices and minimize concerns about 42



### water quality in customer plumbing. 43

44



### Dedicated sampling stations s hould be of metal construction, have unthreaded nozzles or 45



### a design approved by the State, and be located so as to be representative of the water in the 46



### distribution system. They are typi cally covered to protect them from birds, insects, dirt and other 47



### sources of outside contamination. Freezing of de dicated sampling taps ha s occurred in northern 48



### climates and that possibility should be considered when deciding whether and how to install such 49

### DRAFT

Proposed Revised Total Coliform Rule 4-8 August 2010

Assessments and Corrective Actions Guidance Manual 

### taps. Figure 4-1 is a graphic schematic detailing the components of a dedicated sampling station. 1



### Figure 4-2 is a photograph of a dedicated sampling station. 2

3



### Additional guidance on selection of an appropr iate sample tap, including factors such as 4



### type of tap and sink, can be f ound in Narasimhan et al. 2004. 5

6

7

8

9

10

11

Source: Water Distribution System Operation and Maintenance, A Field Study Training Program. USEPA Office of Drinking 12

Water and California Department of Health Services, Sanitary Engineering Branch. Hornet Foundation Inc., Sacramento, Calif. 13

(1989, 2nd ed.). 14

15



### Figure 4.1: Dedicated Sampling Station Schematic 16

17

### DRAFT

Proposed Revised Total Coliform Rule 4-9 August 2010

Assessments and Corrective Actions Guidance Manual 1

Source: With permission courtesy of Koraleen Enterprises. 2

3



### Figure 4.2: Dedicated Sampling Station 4

5

6



### 4.2.4 Maintenance of Adequate Pressure 7

8



### Pressure losses can occur in the distribution sy stem as a result of events such as flushing, 9



### main breaks, power outages, service line breaks, and fires. Pressure transients (also called 10



### pressure surges or water hammer) can occur when an abrupt change in water velocity occurs due 11



### to a sudden valve closure, pump shutdown or star tup, or loss of power. The resulting pressure 12



### wave, with alternating low and high pressures, travels back and forth through the distribution 13



### system until the pressure is stabilized. Low pr essure conditions in the distribution system can 14



### allow a flow reversal or back flow of non-potable water to en ter the system from a cross 15



### connection or other source such as intrusion. Pressure transi ents can also create hydraulic 16



### disturbances that allow biofilm material on pipe surfaces to enter the bulk water. Systems should 17



### check with their State regarding distribution system pressure requi rements. Industry guidelines 18



### suggest that system pressure should be maintained within the range of 35 to 100 psi at all points 19



### in the distribution system (AWWA 1996). Th e AWWA G200 standard indicates that the 20



### minimum residual pressure at the service c onnection under all operati ng conditions should be 21



### greater than 20 psi (AWWA 2004). Many states also have guid elines regarding distribution 22



### system operating pressure. Written standard op erating procedures for pump, hydrant and valve 23



### operation under routine and emergency condition s can help minimize sudden changes in water 24



### velocity that impact system pressure. 25

26



### Other actions that can help to maintain an adequate pressure in the distribution system 27



### include building new booster pump stations and el evated storage facilities, modifying existing 28



### high services pumps, and installi ng variable frequency drives, surge relief valves, and surge 29



### tanks. 30

31



### Booster Pumping Stations 32

33



### Booster pumping stations are used in the di stribution systems to move water from lower 34



### pressure zones to higher pressure zones and to maintain pressure at desirable levels. As the 35

### DRAFT

Proposed Revised Total Coliform Rule 4-10 August 2010

Assessments and Corrective Actions Guidance Manual 

### water system grows and changes, existing boos ter pump stations may no longer be able to 1



### maintain the desired pressure across the distributi on system. In those cases, the construction of a 2



### new booster station may be required. The cons truction of a completely new booster pump 3



### station is not always required to maintain an ap propriate pressure in a water system. There may 4



### be situations where a modificat ion or replacement of an exis ting pump is sufficient. 5

6



### Variable Frequency Drive 7

8



### A variable frequency drive (VFD), also calle d a variable speed drive, allows a booster 9



### pump to supply the required amount of flow based on system demand with a pressure set point to 10



### maintain constant system discharge pressure, co ntrolled to within a few psi of an operator– 11



### adjustable system pressure set point. VFDs wo rk with a system pressure transmitter to control 12



### the system pressure set point. 13

14



### Elevated Storage Facilities 15

16



### Elevated storage is provided within the dist ribution system to supply peak demand rates 17



### and equalize system pressures. In certain sy stems, elevated storage is more effective and 18



### economical than ground storage because by natu re of its elevated location, pumping 19



### requirements may be reduced, and the storage ca n serve as a source of emergency supply since 20



### system pressure requirements can still be met temporarily when pumps are out of service. 21



### Elevated storage tanks are often sited in ar eas having the lowest system pressures during 22



### intervals of high water use. These areas are often those of greatest water demand or those 23



### farthest from pump stations. Elevated tanks are generally lo cated at some distance from the 24



### pump station serving a distribut ion pressure level, but ideally are not placed outside of 25



### boundaries of the service area unless the facility can be located on a nearby hill. Elevated tanks 26



### are built on the highest available ground so as to minimize the required c onstruction cost and the 27



### height requirements. 28

29



### Surge Relief Valves 30

31



### Surge relief valves provide pressure manageme nt by ejecting water out of a side orifice to 32



### prevent excessive high-pressure surges and can also be triggered to open on a downsurge in 33



### pressure in anticipation of an upsurge to follow. Surge relief valves must always be used with 34



### caution for they can make low-pres sure conditions in a line worse than they would be without the 35



### valve. 36

37



### Surge Tanks 38

39



### The four common types of surge tanks in clude pneumatic or closed tanks, open 40



### standpipes (or air chambers), one-way surge tanks (allows water to flow only from the tank into 41



### the pipeline), and two-way surge tanks (allows flow to and from the tank). If water is stored in 42



### these tanks for long periods of time, the water may lose its disinfectan t residual and microbial 43



### growth and other water quality problems may results. Proper operations and maintenance of 44



### surge tanks is required to pr event poor quality or contamin ated water from entering the 45



### distribution system. 46

47



### Hydropneumatic tank systems are a popular way to provide pressure control and 48



### stabilization in smaller water distribution systems; however, they are not t ypically used in larger 49

### DRAFT

Proposed Revised Total Coliform Rule 4-11 August 2010

Assessments and Corrective Actions Guidance Manual 

### systems. A hydropneumatic tank system allows fo r fluctuations in wate r distribution system 1



### pressure, and a potential cushion against water hammer. The system also minimizes booster 2



### pump on-off cycles so that a recommended frequency of 10-15 cycles per hour can be 3



### maintained. 4

5



### The pressure tank uses a compressed air head -space to maintain system pressure. As 6



### water system demand increases, water in the pr essure tank discharges into the system and 7



### reduces the pressure tank’s water level, whic h expands the air cushion above the water and 8



### decreases the tank air pressure. When the air re aches a determined set point, the air compressor 9



### comes on to recharge the air space and cycles off wh en the high pressure set point is met. If the 10



### water demand continues to increase, the booster pumps will cycle on at the low water level and 11



### replenish the water level in the pressure tank. Th e pressure tank must be sized correctly, because 12



### its size determines the frequency of pump cycling. 13

14



### 4.2.5 Maintenance of Appropriate Water Age, Hydraulic Residence Time, and Mixing 15

16



### Water quality problems associated with incr eased water age include reduced disinfectant 17



### residual, increased microbial ac tivity, nitrification, a nd/or taste and odor problems. As water 18



### travels through the distribution system, chlorine continues to react with natural organic matter 19



### (NOM) to form disinfection by-products (DBPs). Thus, increased water age can also lead to 20



### higher DBP concentrations. Water systems shoul d develop an overall strategy to manage the 21



### water age in their distribution systems, while cons idering the need to have adequate storage for 22



### emergencies. Establishing a water age goal is system-specific depending on system design and 23



### operation, water demands, and water quality (e.g., DBP formation potential). In the US, the 24



### average distribution system retention time is 1.3 da ys and the average maximum retention time is 25



### 3.0 days based on a survey of 800 medium a nd large water utilit ies (AWWA and AwwaRF 26



### 1992). Water age can be controlled through a vari ety of techniques including management of 27



### finished water storage facilities, looping of d ead-ends, and re-routing of water by changing valve 28



### settings. Additional guidance is provided in the AwwaRF report, Managing Distribution System 29



### Retention Time to Improve Water Quality (Brandt et al. 2004). 30

31



### Looping Dead-Ends 32

33



### Dead-end pipes often result in stagnant wa ter conditions where water age increases, 34



### which can cause water quality problems. One of th e solutions to address th e stagnant water issue 35



### is looping of dead-ends. However, looping shoul d be evaluated carefully on a case-by-case basis 36



### as it may not actually reduce the long de tention times present in those areas. 37

38



### Installing Appropriate Main Sizes 39

40



### Most distribution systems have been designed to meet a minimum hydraulic capacity. 41



### Additional capacity is generally included at th e design stage to accommodate for future growth 42



### or to allow more flexibility in the configura tion of a distribution system network. A PWS may 43



### also have a policy to limit the num ber of different pipe diameters within the system in order to 44



### simplify construction and maintenan ce. Consequently, network pipe s tend to be larger than is 45



### necessary to meet the daily de mand from the network leading to increased retention time. 46



### Hence, there can be an option to replace mains with smaller diameter pipes but still maintain the 47



### required hydraulic capacity. 48

49

### DRAFT

Proposed Revised Total Coliform Rule 4-12 August 2010

Assessments and Corrective Actions Guidance Manual 1

2



### Installing Automated Flushing Devices 3

4



### Automated flushing devices are used to purge accumulated sediments at low spots and 5



### dead-ends of pipelines at regular intervals, and to drain pipelines for repairs, maintenance, and 6



### inspection. These devices are best suited to rura l networks in which security of the units and 7



### disposal of the water flushed is less problematic. An additional drawback of installing these 8



### devices is the volume and value of the wasted water may be unacceptable. However, in 9



### networks with long pipe runs terminating in dead -ends, there may be few vi able alternatives to 10



### flushing for controlli ng retention time. 11

12



### Storage Facility Modifications 13

14



### Most storage facilities have been designed focusing more on quantity, cost, service life, 15



### appearance, and shape than on maintaining water qua lity. Water quality in storage facilities is 16



### affected by the mixing patterns that occur prim arily during the filling cycle, the long term 17



### residence time, and the interaction between thes e two phenomena. Old water in stagnant zones 18



### can often have very high DBPs and low to no disi nfectant residual. This water can be released 19



### into the system during periods of high demand. Increasing volume tur nover reduces the average 20



### hydraulic residence time (HRT) in finished wa ter storage facilities, thereby reducing DBP 21



### formation, loss of disinfectant, and microbial growth. Kirmeyer and Friedman (2000) 22



### recommend complete turnover every three to five days but suggest that water systems establish 23



### their own turnover goal based on system-specific n eeds and goals. Improving mixing in finished 24



### water storage facilities can help eliminate st agnant zones. Mi xing can be improved by 25



### increasing inlet momentum, changing the inlet c onfiguration, increasing the fill time, and by 26



### installing mixing devices with in the storage facility. 27

28



### It may be necessary to reduce the water volum e in a storage tank or increase demand on 29



### the tank to achieve increased volume turnover. Decommissioning storage facilities may be an 30



### appropriate strategy to reduce wa ter age if existing facilities ar e oversized and not needed for 31



### emergency conditions, fire protection, or for maintaining system pre ssure. A professional 32



### engineer should review system needs, system design, and operation to determine if the existing 33



### storage capacity and tank operation are appropriate. 34

35



### Inlet/outlet configuration 36

37



### Inlet and outlet configuration are critical in the development of proper mixing in a 38



### finished water storage facility. The inlet structur e should be located and si zed to disperse the jet 39



### into the storage facility as we ll as to maintain a jet sufficien t for mixing. In particular, the 40



### location and orientation of the inlet pipe relative to the tank walls can have a significant impact 41



### on mixing characteristics. The physical modifica tions to the inlet pipe for improving mixing 42



### within the tanks include: 43

44



### • Changing the orientation of the inlet pipe and/or 45



### • Decreasing the inlet diameter to increase the jetting action. 46

47



### The outflow configuration doe s not significantly influence mixing, but operation of the 48



### inlet and outflow are important because flow ente ring the tank and leaving the tank at the same 49

### DRAFT

Proposed Revised Total Coliform Rule 4-13 August 2010

Assessments and Corrective Actions Guidance Manual 

### time can negatively impact mixing and should be a voided. Furthermore, wh en the inlet/outlet is 1



### a common pipe, the ability to reduce the inlet diam eter to achieve a higher inflow velocity and 2



### better jetting action will be constrained by the need to maintain an outflow capacity adequate to 3



### satisfy system operational and fire flow require ments. For this reason, it is recommended to 4



### eliminate common inlet/outlet pipes. 5

6



### Installation of mixing devices 7

8



### Mixing the storage facility contents to redu ce stagnant zones can also be accomplished by 9



### installing mixing devices. Special precautions are needed with mechanical mixing devices 10



### because of potential contamination to finished water by the mixer mechanism lubrication system. 11



### Multiple mixing devices may be needed and the PWS should consider the increased maintenance 12



### requirements inside the storage facility. 13

14



### Increasing volume turnover 15

16



### As mentioned earlier in this section, incr easing the volume turnove r reduces the average 17



### HRT in the storage tank. Turnover can be acco mplished by making operational modifications to 18



### the storage tank such as increasing the water le vel fluctuation or drawdown between fill and 19



### draw cycles. The water level should be lo wered in one continuous operation not in small 20



### incremental drops throughout the day. 21

22



### Operational modifications may be limited by the following considerations: 23

24



### • Control of flow rates during tank filling ma y be needed to minimize the potential for 25



### low pressure in the distribution system; 26



### • Changes in operating protocol for booster st ations and other tanks to achieve turnover 27



### while maintaining adequate pressure system-wide. 28

29



### 4.2.6 Maintenance of Storage Facility 30

31



### Finished water storage tanks are an important component of a PWS’s distribution system. 32



### Tanks are usually designed for th ree purposes: reduce pressure fl uctuations in the distribution 33



### system, equalize water demands, and provide water reserves for emergencies such as fires and 34



### power outages. 35

36



### The two main categories of water storage tanks include ground storag e tanks and elevated 37



### storage tanks (see previous discussion on el evated storage tanks in Chapter 4.2.5). Ground 38



### storage tanks can be below grade, partially be low grade, or at ground level in a distribution 39



### system and are usually constructed of a variet y of materials, includi ng steel, concrete, and 40



### fiberglass reinforced plastic. Elevated storag e tanks are typically constructed of steel. 41

42



### Contamination from birds and insects can be a source of microbial contamination in the 43



### distribution system. Maintenan ce on a storage tank can signifi cantly reduce the possibility of 44



### contamination or recontamination. Some actio ns include inspecting and cleaning, lining the 45



### interior of the tank, repairing vents and/or hatches, and repair ing the tank itself. 46

47



### Inspection / Cleaning of Tanks 48

49

### DRAFT

Proposed Revised Total Coliform Rule 4-14 August 2010

Assessments and Corrective Actions Guidance Manual 

### Tank inspections can provide useful informati on on the physical condition of the exterior 1



### and interior of the tank, identifying potential so urces of microbial contamination. Inspections 2



### can also identify the accumulation of sediment with in storage tanks due to particle settling in the 3



### tank or the dissolving of cementitious materials of a concrete tank from soft, low alkalinity, low 4



### pH waters. There are several wa ter quality issues associated w ith sediment buildup in a storage 5



### tank, including increased disinfection demand, microbial growth, disinfection by-product 6



### formation, and increased turbidity. 7

8



### Lining of Storage Tanks 9

10



### Lining the interior of a water st orage tank is another action that can be taken to reduce the 11



### potential for coliform contamina tion and recontamination of a distribution system. Corrosion 12



### and corrosion product buildup from excessive interi or corrosion can also result in water quality 13



### issues such as increased di sinfection demand, microbial grow th, and increased turbidity. 14

15



### Vent / Hatch Repair 16

17



### One of the most common sources of contam ination in a water storage tank is the 18



### improper design and maintenance of vents and roof hatches. These accessories can provide entry 19



### points for debris as well as microbial contaminati on from birds and insects. Aging water storage 20



### tanks with damaged tank covers can also be a source of microbial contamination. To prevent 21



### contamination and recontamination of the wate r supply, damaged vents, hatch roofs, and tank 22



### covers should be repaired or replaced immediately. 23

24



### Tank Repair 25

26



### Aging water storage tanks can provide entry points for debris as well as microbial 27



### contamination from birds and insects and should be replaced or repaired immediately to prevent 28



### contamination and recontamin ation of the water supply. 29

30



### 4.2.7 Implementation or Upgrade of a Cross-c onnection Control and Backflow Prevention 31



### Program 32

33



### Implementing a Cross-connection Control a nd Backflow Preventi on (CCCBFP) Program, 34



### including the installation of backflow prevention assemblies and devices, can prevent the flow of 35



### non-potable substances into the distribution system. When implementing the CCCBFP Program, 36



### the drinking water system should a dhere to applicable State and/or local criteria, codes, and/or 37



### regulations. Some codes or re gulations may include documenting installation procedures and the 38



### periodic testing of backflow prevention assemblies. CCCBFP can prevent the introduction of 39



### non-potable substances into the public water supp ly due to backsiphonage or backpressure. 40

41



### Backflow prevention equipment installation and maintenance is generally the consumer’s 42



### responsibility. However, depending on how a sy stem implements the CCCBFP, the customer 43



### and the PWS can share costs for the equipment and equipment installa tion, inspection, testing, 44



### and maintenance. The PWS, on the other hand, is primarily responsible for the administration of 45



### cross-connection control and backflow prevention and the inspection, review , and approval of all 46



### backflow prevention assemblies and devices. 47

48

### DRAFT

Proposed Revised Total Coliform Rule 4-15 August 2010

Assessments and Corrective Actions Guidance Manual 

### 4.2.8 Sampler Training 1

2



### Implementation of a sampler training program provides guidelines for procedures that 3



### samplers must follow to collect valid, uncontaminated samples for analysis of total coliforms in 4



### the distribution system. Traini ng sessions for operators reinfo rce proper sampling and sample 5



### handling procedures to obta in uncontaminated samples. 6

7



### 4.2.9 Addition or Upgrade of On- line Monitoring and Control 8

9



### Currently, monitoring of total coliforms is performed through grab samples at the 10



### treatment plant and throughout the distribution system . These grab samples are then analyzed in 11



### a laboratory to determine whether total coliforms are present or not in the grab sample. To 12



### ensure sufficient treatment has been provided, grab sample results, disinfectant dosages, and 13



### certain water quality parameters, such as disinfec tant residual levels, can be correlated. Since 14



### automatic monitoring is not available for total co liforms, PWSs can instead automatically control 15



### and monitor for disinfectant dosages and water quality parameters. 16

17



### Water Quality Monitoring and Control 18

19



### The ability of a PWS to monitor disinfectan t residuals in the distribution system can 20



### allow the PWS to determine if there is an area of possible contamination or an area that requires 21



### additional treatment. Low levels of disinfectant residuals in a system can be caused by an 22



### increase of organics in a system, which c onsume disinfectant resi duals, or insufficient 23



### disinfectant dosages at the treatm ent facility. Maintenance of su fficient disinfectant residual 24



### levels in a distribution system is important in maintaining minimal levels of total coliforms in the 25



### system. 26

27



### Disinfectant residual can be monitored using r outine grab samples, with adjustment of 28



### dosages based on results. Controlling and mon itoring disinfectant dosa ges and water quality 29



### parameters can also be performed through the us e of a Supervisory Control and Data Acquisition 30



### (SCADA) system at the treatment facility. Di sinfectant dosing equipment can be monitored and 31



### analyzers can be placed in the treatment proc ess to monitor water quality parameters. 32



### Monitoring water quality parameters via SCADA in a distribution system is possible; however, it 33



### can be costly. Determining the number and loca tion of the analyzers is challenging and highly 34



### dependent upon the system size. Typically, anal yzer equipment will draw samples from an 35



### above grade pipe or a sample tap to an analyzer that is placed in a building. Sample locations 36



### will require analyzer equipment, a building, electr ic power, and, in the case of some systems, 37



### integration to the PWS’s existing SCADA system. Method requirements for on-line 38



### amperometric chlorine monitors are more tim e intensive and difficult than grab sampling. 39

40



### Pressure Monitoring and Control 41

42



### In addition to water quality monitoring, a PWS can monitor pressure levels throughout 43



### the distribution system. Installing online pres sure monitoring and control will help minimize 44



### future incidents of pressure loss that can allow en try of contaminants into the distribution system. 45



### It can also help determine if there are any physic al problems in the system, e.g., a crack in a pipe, 46



### a leaking valve, etc., that cause changes to the wa ter quality of the system. Pressure readings can 47



### also be used to help locate ar eas of deficiency in a distributio n system. Similar to the water 48



### quality monitoring, determining the number of pre ssure monitors and their locations is dependent 49

### DRAFT

Proposed Revised Total Coliform Rule 4-16 August 2010

Assessments and Corrective Actions Guidance Manual 

### upon the system size. Pressure monitoring locatio ns will also require the same equipment as 1



### water quality sampling locations. 2

3



### On-line distribution system monitoring thr ough the SCADA system ca n alert operators if 4



### there are possible issues with th e distribution system; however, m onitoring the water quality or 5



### pressure will not identify the source of the c ontamination nor will it necessarily identify the 6



### location of the contamination. 7

8



### 4.2.10 Addition of Security Measures 9

10



### Systems may need to install security measures in circumstances where the assessment or 11



### onsite inspection reveals vandalism or security br eaches that could lead to water contamination. 12



### Measures that a water system may take to correc t security breaches include installing a fence or 13



### locking buildings to restrict access to the syst em. Other possible security measures include 14



### employing a full time, on-site security staff and using alarms and cameras to detect security 15



### breaches. 16

17



### Water systems should prioritize their secur ity measures and concentrate on the most 18



### vulnerable parts of the system, such as unstaffed facilities (e.g., finished water storage tanks). 19



### An important implementation issue is determining the extent to which the water system needs to 20



### be secured. This would depend on how widely spread the system/facility is, the number and 21



### complexity of the treatment trains, the extent of the watershed, the distance of the treatment plant 22



### from the influent wells, accessibil ity of the distribution system, etc. 23

24



### Installing security measures can increase the public’s confidence in th e protection of their 25



### drinking water and indeed can provide substantia l protection against vandalism that might result 26



### in contamination of the water. However, security measures are not always foolproof or absolute 27



### in combating vandalism or security breaches. 28

29



### 4.2.11 Development and Implementation of an Operations Plan 30

31



### A water system should develop a distribution system operations plan to integrate all 32



### operations and maintenance functions to meet the goals of flow, pressure and water quality. The 33



### AWWA G200-04 standard describe s the critical requirements for the effective operation and 34



### management of drinking water dist ribution systems. According to this standard, a water system 35



### should develop standard operating procedures (SOPs), comprehensive monitoring plans, routine 36



### inspections, and emergency response plans. 37

38



### Develop Standard Operating Procedures (SOPs) 39

40



### SOPs should be developed for each operati on and maintenance function that affects 41



### system water quality (e.g., flushing programs, st orage facility inspections). The water quality 42



### goals for both the distribution system and the partic ular function should be sp ecified in the SOP. 43



### SOPs should be developed from information gath ered from the various departments and crews 44



### involved in a given function. The SOPs s hould be written in terms that everybody will 45



### understand and they should include all activities needed to conduct the procedures, and describe 46



### the labor, equipment and materials needed to complete the activity. 47

48



### Develop Sampling Plan 49

### DRAFT

Proposed Revised Total Coliform Rule 4-17 August 2010

Assessments and Corrective Actions Guidance Manual 1



### The water system should establish a routine distribution system sampling plan that is 2



### representative of the entire dist ribution system. At a minimum, the sample sites should include 3



### sites required for regulatory compliance monito ring. Additional sites should be sampled as 4



### necessary to provide a complete picture of the water quality in the system. All samples should 5



### be collected in accordance w ith the latest edition of Standard Methods for the Examination of 6



### Water and Wastewater (APHA et al. 2005). 7

8



### Perform Routine Inspections 9

10



### Routine inspections of various distribution system components such as finished water 11



### storage facilities, water mains, pump stations, chemical storage facilities, valves, and fire 12



### hydrants are necessary to ensure high-quality water. The water systems should implement 13



### inspection and maintenance programs of these component s as part of the SOPs. 14

15



### Develop Emergency Response Plan 16

17



### A written emergency response plan for the di stribution system allows operating personnel 18



### to respond efficiently, effectively and rapidly to an emergency situation. Water quality system 19



### safety and reliability are improved if a wate r system has an emergency response plan. 20

21



### Utilize Appropriately Qualified Operators 22

23



### EPA established an operator certification pr ogram with minimum professional standards 24



### for the operation and maintenance of water system s. The EPA program issued guidelines that 25



### specify standards for certification and recertif ication of operators. States implement the 26



### minimum standards of the certification program guidelines. While th e specific requirements 27



### vary from state to state, the goal of the program is to ensure that sk illed professionals are 28



### overseeing the treatment and distribution of safe drinking water and compliance with the Safe 29



### Drinking Water Act. More information on the op erator certification program can be found at: 30



### http://www.epa.gov/safewater/ope ratorcertification/index.html

. 31

32



### Providing training sessions for operators rein force proper operation and maintenance of 33



### these facilities and systems. These sessions can also help educate PWS staff on emerging 34



### treatment technologies, regulator y requirements, and other adva nces in the drinking water 35



### industry. 36

37



### 4.3 Best Practices 38

39



### Best practices are actions th at systems should and/or might choose to take following a 40



### Level 1 or Level 2 trigger regardle ss of whether a sanitary defect or likely cause is identified, or 41



### following any total coliform or E. coli occurrence (e.g., a single E. coli -positive sample). They 42



### can range from temporary measures to long term measures. 43

44



### In the survey conducted by AWWA, AM WA, ASDWA (see footnote 8), most 45



### respondents indicated that follow- up actions are taken following a positive coliform result even 46



### when the underlying cause is unidentified. System s take these actions to ensure public health 47



### protection and generally do not i nvolve major construction or capital improvement. Examples of 48



### common actions that were reported are flushi ng, increasing disinfectan t residual, collecting 49

### DRAFT

Proposed Revised Total Coliform Rule 4-18 August 2010

Assessments and Corrective Actions Guidance Manual 

### additional investigative samples, examining whet her samples were collected from appropriate 1



### sample sites, and re-training staff/sampler on pr oper sampling procedures. Based on the results 2



### of the survey, the list below includes these actio ns and a few other ones as examples of best 3



### practices that systems may take following an a ssessment trigger or a positive coliform result, 4



### regardless of whether the cause or the sanitary defect is identifie d. Some of them have already 5



### been discussed in Chapter 4.2 of this document. These actions are not mutually exclusive and 6



### systems may choose to implement a combination of them if appropriate. Systems should also 7



### consider implications for long- term sustainability and public h ealth protection when deciding 8



### which of these actions to implement. 9

10



### The proposed RTCR also identifies a list of “b est technologies, trea tment techniques, or 11



### other means” (also known as best available techno logies or BATs) to help systems comply with 12



### the rule (see §141.63(e) of the proposed RTCR). They includ e appropriate well placement and 13



### construction, maintenance of a disinfectant residual throughout the distri bution system, proper 14



### maintenance of the distribution system, f iltration and disinfection of surface water, 15



### implementation of a cross-connection control program, and implementation of a wellhead 16



### protection program. Systems may choose to take a dvantage of these BATs when they trigger an 17



### assessment in order to avoid future triggers and/ or violations, even if they are unable to find a 18



### likely cause/sanitary defect. Some of these BATs are also discussed in the list below. 19

20



### • Apply disinfection – A discussion of disinfection pract ices is in Chapter 4.2.1 of this 21



### document. Additional information on emerge ncy disinfection practi ces can be found at 22



### http://www.epa.gov/safewater/faq/emerg.html 23

24



### • Change or update distribution system maintenance operations – A well-maintained and 25



### operated distribution system is an importa nt barrier in protecting water quality. Even if 26



### water from an extremely clean source is adequately treated, breakdowns in the 27



### distribution system can lead to waterborne illn esses. In particular, the contamination of 28



### treated water can result from m ain breaks, inadequate water pressure that allows intrusion 29



### or backflow of contaminants, deficiencies in storage tanks, and inadequate separation of 30



### water supply lines and sewers. 31

32



### Proper maintenance of the distribution system includes appropriate pipe replacement and 33



### repair procedures, main flushing programs, proper operation and maintenance of storage 34



### tanks and reservoirs, cross-connection cont rol, and continual maintenance of positive 35



### water pressure in all parts of the distribution system. Ev en if a Level 1 or Level 2 36



### assessment does not reveal an underlying cause for the positive coliform samples, many 37



### systems may choose to change or update thei r distribution system maintenance operations 38



### as a follow-up action. Many of these actions are described in Chapters 4.2.3 to 4.2.7 of 39



### this document. 40

41



### • Perform unscheduled or spot flushing – A discussion of unschedul ed or spot flushing is 42



### in Chapter 4.2.2 of this document. 43

44



### • Implement sampler training – A discussion of sampler traini ng is in Chapter 4.2.8 of this 45



### document. 46

47

### DRAFT

Proposed Revised Total Coliform Rule 4-19 August 2010

Assessments and Corrective Actions Guidance Manual



### • Review sample siting plan – The sample siting plan should en sure that the quality of the 1



### water is representative of the distribution sy stem. Utilities might consider reviewing and 2



### revising their sample siting plan as a universal follow-up action, regard less of whether an 3



### underlying cause for the positive coliform samples can be identified. 4

5



### • Select appropriate sample sites – Part of a successful sampling plan is the selection of 6



### clean, appropriate sample taps and sites from wh ich to collect representative samples. In 7



### addition to reviewing the sample siting plan, systems may wish to consider the use of 8



### dedicated sample taps, which is discu ssed in Chapter 4.2.3 of this document. 9

10



### • Institute boil water orders – A number of systems have c hosen to institute boil water 11



### orders even in cases where total coliforms are detected but no E. coli is present. In some 12



### States, boil water orders are a required fo llow-up action after a total coliform-positive 13



### sample has occurred. However, it should be noted that requirements vary from state to 14



### state and systems should follow State require ments for implementing boil water orders, 15



### whether they are required in response to a total coliform-positive or not. 16

17



### A boil water order requires that systems public ly advertise that water should be boiled 18



### prior to consumption. While a boil water order can be protective of public health, it also 19



### requires effort for consumers, has economi c impacts to businesses, and can undermine 20



### public confidence in the water supply. Th erefore a boil water order should not be 21



### implemented lightly and should be reserved fo r situations with si gnificant potential to 22



### impact public health. A Level 2 trigger associated with an E. coli- positive may be more 23



### appropriate for a boil water order action than a Level 1 trigger associated with a total 24



### coliform-positive. Boil water orders may also be issued on a voluntary basis and may be 25



### helpful for educating sensitive populations. 26

27



### 4.4 Simultaneous Compliance Issues 28

29



### As mentioned previously, the in terrelated nature of regulat ions can be a challenge as 30



### adjustments to improve compliance for one rule ma y inadvertently affect a system’s ability to 31



### comply with another rule. Given that tem porary disinfection is a common corrective action 32



### taken by systems that have experienced positive coliform results, a number of related issues are 33



### important to keep in mind. 34

35



### NTNCWSs and CWSs that do not typically practice disinfection and are planning on 36



### adding temporary disinfection are subject to the Stage 1 and Stag e 2 Disinfectants/Disinfection 37



### By-Products Rules (DBPRs) (40 CFR 141.130 and 141.600) (USEPA 1998b; USEPA 2006a) for 38



### the monitoring period in which the disinfectant is used. Systems should check with their States 39



### to determine what the requirements are for compliance with the rules. For temporary 40



### disinfection by chlorine or chloramines, the syst em will have to ensure that maximum residual 41



### disinfectant levels (MRDLs) for chlorine/chloram ines and maximum contaminant levels (MCLs) 42



### for total trihalomethanes (TTHM) and the gr oup of five haloacetic acids (HAA5) are not 43



### exceeded. 44

45



### Alkalinity and pH adjustment a nd/or the addition of corrosion i nhibitors are often used to 46



### meet Lead and Copper Rule (LCR) (40 CFR Part 141, Subpart I) requirements. Systems that are 47



### using measures such as these should also be awar e that the pH of the water can alter the efficacy 48



### of the disinfectant. For a given level of inactivation, the higher the pH, the higher the 49

### DRAFT

Proposed Revised Total Coliform Rule 4-20 August 2010

Assessments and Corrective Actions Guidance Manual 

### disinfection detention time a nd/or chlorine residual c oncentration required. See Revised 1



### Guidance Manual for Selecting Lead and Copper Control Strategies (USEPA 2003) for more 2



### information on simultaneous compliance with th e LCR and other drinking water regulations. 3

4



### Systems should also be aware that changes in disinfectant residual may alter the 5



### corrosivity of the water. Chlorine is a power ful oxidant and reacts with many metals that are 6



### present in the distribution syst em. Rapid changes between high concentrations and low (or no) 7



### concentrations of oxidants can destabilize metal scales that fo rm along the pipe wall, possibly 8



### allowing for metal release into the water. 9

10

11

12Proposed Revised Total Coliform Rule 5-1 July 2010

Assessments and Corrective Actions Guidance Manual 

## 5. References

American Public Health Association (APHA), Wa ter Environment Federation (WEF), and American

Water Works Association (AWWA). 2005. Standard Methods for the Examination of Water and

Wastewater, 21 st Edition, Washington, DC .

AWWA, 1996. Water Transmission and Distribution . Denver, CO. AWWA

AWWA, 2004 . G200 –Standard for Distribution Systems Operation and Management . Denver, CO.

AWWA, 2008. Reliable Coliform Sampling for Water Systems, DVD, Denver, CO.

AWWA and AwwaRF. 1992. Water Industry Da ta Base: Utility Profiles. Denver, CO.

Brandt, M. J., J. Clement, J. Powell, R. Casey, D. Holt, N. Harris, and C.T. Ta. 2004. Managing

Distribution System Retention Time to Improve Water Quality , Denver, CO: AWWARF.

Clark, R.M., E.E. Geldreich, K.R. Fox, E.W. Rice, C.H. Johnson, J.A. Goodrich, J.A. Barnick, F.

Abdesaken, J.E. Hill, and F.J. Angulo. 1996. A Waterborne Salmonella typhimurium outbreak in

Gideon, Missouri: results from a field investigation, International Journal of Environmental

Health Research 6:187-193.

Edberg, S.C., E.W. Rice, R.J. Karlin and M. J. Allen. 2000. Escherichia coli: the best biological drinking

water indicator for public health protection. Journal of Applied Microbiology 88:106S-116S.

Great Lakes – Upper Mississippi River Board of Stat e and Provincial Public Health and Environmental

Managers, Water Supply Committee. 2007. Recomm ended Standards for Water Works. Albany,

NY. Available at: http://10statesstandards.com/waterstandards.html [30 Jul 2010].

Helmi, K., S. Skraber, C. Gantzer, R. Willame, L. Ho ffmann, and H.M. Cauchie. 2008. Interactions of

Cryptosporidium parvum, Giardia lamblia, vaccinal poliovirus type 1, and bacteriophages

phiX174 and MS2 with a drinking water biof ilm and a wastewater biofilm. Applied and

Environmental Microbiology. 74:2079-2088.

Kirmeyer, G.J and M. Friedman. 2000. Guidance Manual for Maintaining Distribution System Water

Quality. Denver, CO: AWWARF and AWWA.

Letterman, R.D., A. Amirtharajah, and C.R. O’Me lia. 1999. Coagulation and Flocculation, in Water

Quality and Treatment , 5 th edition. R.D. Letterman, ed., AWWA, Denver, CO.Proposed Revised Total Coliform Rule 5-2 July 2010

Assessments and Corrective Actions Guidance Manual Lieberman, R.J., Shadix, L.C., Newport, B.S., Crout, S.R., Buescher, S.E., Safferman, R.S., Stetler, R.E.,

Lye, D., Fout, G.S., and Dahling, D. 1994. “Source water microbial quality of some vulnerable

public ground water supplies.” Proceedings, Wa ter Quality Technology Conference, San

Francisco, CA, October, 1994.

Lieberman, R., L. Shadix, B. Newport, and C. Freb is. 2002. Microbial Monitoring of Vulnerable Public

Groundwater Supplies. American Water Works A ssociation Research Foundation, Denver, CO.

162 pp.

Narasimhan, R., J. Brereton, M. Abbaszadegan, A. Alum, and P. Ghatpande. 2004. Sample Collection

Procedures and Locations for Ba cterial Compliance Monitoring , Awwa Research Foundation,

Denver, CO.

Rangel, J.M., P.H. Sparling, C. Crowe, P.M. Griffin and D.L. Swerdlow, 2005. Epidemiology of

Escherichia coli O157:H7 outbreaks, United States, 1982-2002. Emerging Infectious Diseases

11(4):603-609.

Skraber, S., J. Schijven, C. Gantzer, and A.M. de Roda Husman. 2005. Pathogenic viruses in drinkingwater biofilms: a public health risk? Biofilms. 2:105-117.

Stanford, B., A. Pisarenko, S. Snyder, and G. Gordon. The Formation of Perchlorate, Bromate, and Other

Contaminants in Hypochlorite Solutions: Impli cations for Water Utilities. Proceedings from

Water Quality Technology Conference & Expedition. Seattle, Washington. November 18, 2009.

USEPA and California Department of Health Servic es. 1989. Water Distribution System Operation and

Maintenance, A Field Study Training Program, 2 nd ed. Hornet Foundation Inc., Sacramento, CA.

USEPA. 1998a. National Primary Drinking Water Regulations: In terim Enhanced Surface Water

Treatment Rule; Final Rule. 63 FR 23361 (April 28, 1998).

USEPA. 1998b. National Primary Drinking Water Re gulations: Stage 1 Disinfectant Disinfection

Byproduct Rule; Final Rule. 63 FR 69390. (December 16, 1998).

USEPA. 2001. A Small Systems Guide to the Total Coliform Rule (EPA 816-R-01-017a). Available at:

http://www.epa.gov/safewater/disinfection /tcr/pdfs/guide_tcr_smallystemsguide.pdf [21 Jun

2010].Proposed Revised Total Coliform Rule 5-3 July 2010

Assessments and Corrective Actions Guidance Manual USEPA. 2003. Revised Guidance Manual for Selecti ng Lead and Copper Control Strategies (EPA-816-R03-001). Available at

http://www.epa.gov/ogwdw/lcrmr/pdfs/guidan ce_lcmr_control_stratageis_revised.pdf [20 Jul

2010].

USEPA. 2006a. National Primary Drinking Water Re gulations: Stage 2 Disinfectant Disinfection

Byproduct Rule; Final Rule. 71 FR 388. (January 4, 2006).

USEPA. 2006b. National Primary Dr inking Water Regulations: Ground Wa ter Rule; Final Rule. 71 FR

65574. (November 8, 2006).

USEPA. 2006c. Total Coliform Rule White Paper: Causes of Total Coliform-Positive Occurrences in

Distribution Systems. Available at:

http://www.epa.gov/safewater/disinfec tion/tcr/pdfs/issuepaper_tcr_causes.pdf [23 Mar 2010].

USEPA. 2006d. Total Coliform Rule: A Handbook for Small Noncommunity Water Systems serving less

than 3,300 persons: One of the Simple Tool s for Effective Performance (STEP) Guide Series

(EPA 816-B-06-001). Available at:

http://www.epa.gov/safewater/disinfection/tcr/pdfs/stepguide_tcr_smallsys-3300.pdf [21 Jun

2010]

USEPA. 2006e. EPA’s Interactive Sampling Guide fo r Drinking Water Operators (CD-ROM). EPA-816-

C-06-001. http://www.epa.gov/ogwdw000/sma llsystems/samp lingcd.html#one [30 Jul 2010].

USEPA. 2008. Total Coliform Rule / Distribu tion System (TCRDS) Federal Advisory Committee

Agreement In Principle. Available at:

http://www.epa.gov/safewater/disinfection/t cr/pdfs/tcrdsac/agreementinprinciple_tcrdsac_2008-

09-18.pdf [24 Mar 2010].

USEPA. 2010a. Technology and Cost Document for the Proposed Revised Total Coliform Rule . EPA815-R-10-002.

USEPA. 2010b. National Primary Drin king Water Regulations: Revisions to the Total Coliform Rule.75

FR 40926. (July 14, 2010).A-1 

### Appendix A

Example Assessment Forms

The following are examples of Level 1 and Level 2 assessment forms developed by the Total

Coliform Rule Distribution System Advisory Committee Technical Work Group.A-2 

## THIS PAGE INTENTION ALLY LEFT BLANKCONCEPT EXAMPLELevel 1 Assessment Form



### A-3 A-3System Name: Source Water: PWSID #System Type: Population Served: PWS Address:Operator in Responsible Charge (ORC): Phone:City, State:County:Person that collected TC samples if different than ORC:Phone:Address, City, State, Zip:Date Assessment Completed:Questions (1-5)Reviewed andchecked?(Type “3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)1. Have any of the following occurred atrelevant facilities prior to the collectionof TC samples?-any interruptionsin the treatment process-any reported loss of pressure events (pressure < 5 psi)-operation and maintenance activities that could haveintroduced total coliform-reported vandalism and/or unauthorized access to facilities-visible indicators of unsanitary conditions reported-any fire fighting event, flushing operation, sheared hydrant, etc.-any sites with low or inadequate disinfectant residual or sites where it is difficult to maintain a residual-any other water quality parameters measured where results were out of the ordinary2. Have there been any recent operational changes to the system?-sources introduced-treatment oroperational changes-potential sources of contamination3. Evaluate sample site.-condition or location of tap-regular use of connection4. Sample protocol followed and reviewed.-flush tap-remove aerator-no swivel-fresh sample bottles-sample storage acceptable5. Distribution System-system pressure-cross connection-pump station-air relief valves-fire hydrants or blow off-breaks-repairsCONCEPT EXAMPLELevel 1 Assessment Form



### A-4 A-4Questions (1-5)Reviewed andchecked?(Type “3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)6. Storage Tank-screens-security-access opening-condition of tank-vent-drain overflow-pressure tank-O&M7. Treatment Process-interruptions-POE/POU-softeners-O&M8. Source - Well-sanitary seal-vent screened-air gap-cross connection-security-pump to waste line9. Source - Spring-condition of spring development-condition of spring box-security10. Source - Surface Water Supply-heavy rainfall-rapid snowmeltNote: Form to be completed based on dataand documents available to the PWS operatorin charge, maintained on file and returned to the Primacy Agency within XX days.Additional Comments:Print name of person completing form:Date:Signature:Reserved for State1.Assessment has been successfully completed.2.Likely reason for total coliform-positive occurrence is established.3.System has corrected the problem.4.Was a reset requested and / or granted? – Rationale5.Name of State reviewer:CONCEPT EXAMPLELevel 2 Assessment Form



### A-5 A-5System Name:Source Water: PWSID #System Type:Population Served: PWS Address:Operator in Responsible Charge (ORC): Phone:City, State:County:Person that collected TC samples ifdifferent than ORC: Phone:Address, City, State, Zip:Date Assessment Completed:QuestionsReviewed andchecked? (Type“3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)1. Have any of the following occurred at relevant facilities prior to the collection of TC samples?a.Were there any operation and maintenance activities that could haveintroduced total coliforms?b. Have there been any interruptions in the treatment process?c. Has the system lost pressure to less than 5 psi?d.Have there been any vandalismand/or unauthorized access tofacilities?e. Are there any visible indicators of unsanitary conditions observed?f.Have there been any analytical results or any additional samplescollected, including source samples which were positive (not forcompliance)?g.Have there been any sites withlow or inadequate disinfectantresidual? Are there sites where it is difficult to maintain a residualwithout flushing?h.Were any other water quality parameters measured and were anyresults out of the ordinary?i.Have there been any community illness suspected of beingwaterborne (e.g., Does the communitypublic health official indicatethat an outbreak has occurred.)j.Did the water system receive any TCR monitoring violations in thepast 12 months? If yes, when.k.What was the most recent date on which satisfactory total coliformsamples were taken?Date: ______________l.Have there been a fire fighting event, flushing operation, shearedhydrant, etc.m. Other comments on records and maintenance?CONCEPT EXAMPLELevel 2 Assessment Form



### A-6 A-6QuestionsReviewed andchecked? (Type“3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)2. Have there been any recenttreatment or operational changes?a.Have any inactive sources recently been introduced into the system(e.g., auxiliary systems)?b. Have there been any new sources introduced into the system?c.Is there evidence of any potential sources of contamination (mainbreaks, low pressure, high turbidity, loss of disinfection, etc.)?3. Evaluate sample sitea.What is the condition of the tap?(Provide comments)b.What is the location of the tap?(Provide comments)c.What is the regular use of the connection?(Provide comments)d.Have there been any plumbing changes or construction? If yes,when and what was the repair or change?e. Have there been any plumbing breaks or failure? If yes, when?f.List any identified cross connections after the service connection orin premise plumbing.(Provide comments)g.Were all of the backflow prevention devices present,operational andmaintained?h.Were there any low pressure events or changes in water pressureafter the service connection or in the premise plumbing? If yes,when?i.Is there any treatment devices after the service connection or inpremise?(Circle response, if applicable)Point of Entry (POE) Point of Use (POU)j. Other comments on sample site?4. Sample protocolfollowed and revieweda.Flush tap, remove aerator, no swivel, fresh sample bottles, samplestorage acceptable5. Distribution Systema.System pressure: Is there evidence that the system experienced lowor negative pressure? If yes, when?b. List any identified cross connections.c.Pump station: Are there any sanitary defects in the pump station?Are pump(s) operable?CONCEPT EXAMPLELevel 2 Assessment Form



### A-7 A-7QuestionsReviewed andchecked? (Type“3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)d.Last pump maintenance/service date.(Respond if applicable)Date: _____________ Maintenance Performed?e.Air relief valves: Is the valve vault subject to flooding or does thevent terminate below grade?f.Fire hydrant/blow off: Are any located in an area with a high watertable or pits?g. Is the distribution system secured to prevent unauthorized access?h.Are the backflow prevention devices at high risk sites present,operational and maintained?i.Have there been any water main repairs or additions? If yes when,and what was the repair or addition?j. Have there been any water main breaks? If yes, when?k.Was there any scheduled flushing of the distribution system? If yes,when?l.Is there any evidence of intentional contamination in the distributionsystem?m. Other comments on the distribution information.6. Storage Facilitiesa. Are the overflow and vents properly screened?b. Is the facility secured to prevent unauthorized access?c. Does the access opening have the proper gasket and seal tightly?d. Could the physical condition of tank be a source of contamination?e.Is the vent turned down and maintaining an approved air gap at thetermination point?f. Does the drain/overflow line terminate at a minimum of 12" air gap?g.If present, is the pressure tankmaintaining an appropriate minimumpressure?h. Has proper O&M been performed?i. Was there any observed physical deterioration of the tank?j. Were there any observed leaks?k.Is there any evidence of intentional contamination at the storagetank?l.Has there been any facility maintenance (i.e. painting/coating)? Ifyes, when?CONCEPT EXAMPLELevel 2 Assessment Form



### A-8 A-8QuestionsReviewed andchecked? (Type“3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)m. Is facility maintenance occurring per appropriate schedule?n.Does the tank "float" on the distribution system or are there separateinlet and outlet lines?o.What is the measured chlorine residual (total/free) of the waterexiting the storage tank today?Residual ____________p.Are there any unsealed openings in the storage facility such asaccess doors, vents or joints?q. Other comments on the storage system7. Treatment Process. (If applicable)a. Treatment devices operational and maintained?b. Is there any recent installation or repair of treatment equipment?c.Were there any recent changes in the treatment process (e.g.,addition of a process, change in chemical or dosage)? If yes, when,what was the change?d.Were there any interruptions of treatment (lapses in chemical feed,turbidity excursions, disinfection)? If yes which part, when and forhow long?e.What is the free chlorine residual measured immediatelydownstream from the pointof application?Residual: ____________f. Did a review of the filter turbidity profiles reveal any anomalies?g. Were there any failures to meet the C x T calculations?h. Were the flow ratesabove the rated capacity?i. Were there any anomalies on the settled water turbidities?j. Other comments on the treatment system.8. Source – Wella. Is the sanitary seal intact?b. Is the vent screened?c. Does the vent and pump to wasteterminate in an approved air gap?d. Are there any unprotected cross connections at the wellhead?e.How is the well used?(Circle if applicable)Primary Backup Emergency Not a PWS Not Drinking Waterf. How far does the casing extend abovegrade? Height ____________ Comments:CONCEPT EXAMPLELevel 2 Assessment Form



### A-9 A-9QuestionsReviewed andchecked? (Type“3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)g. Is the well cap vented?h. Is there evidence of standing water near the wellhead?i. Is the wellhead secured to prevent unauthorized access?j.Have there been any sewer spills, source water spills or otherdisturbances?k.Other comments on the well system. (Are there aspects of wellconstruction and operation that would bear on observed positives?)9. Source – Springa. What is the condition ofthe spring development?b. What is the condition of the spring box?c. Is the spring secured to prevent unauthorized access?d. Other comments on the spring system.10. Source - Surface Water Supplya.Have there been any sewer spills, source water spills or otherdisturbances?b. Have there been any algal blooms?c. Has source water turnover occurred?d. Other source water commentsEnvironmental Eventsa. Has there been heavy rainfall?b. Has there been any rapid snow melt or flooding?c.Have there been changes in available source water (e.g., significantdrop in water table, well levels, reservoir capacity, etc.)d. Have there been any interruptions to electrical power?e. Have there been any extremes in heat or cold?Note : Form to be completed based on data and documents available to the PWS operator in charge, maintained on file and returned to the Primacy Agency within XX days.Additional Comments:CONCEPT EXAMPLELevel 2 Assessment Form



### A- A-10Print name of person completing form: Date:Signature:Reserved for State1. Assessment has been successfullycompleted. Name of State Reviewer:B-1 

### Appendix B

Examples of Completed Assessments

This appendix provides examples of completed Level 1 and Level 2 assessment forms (using the

forms presented in Appendix A). Some States are already requiring some form of assessment

and the completion of an assessment form whenever a PWS has a total coliform-positive sample.

Those States provided EPA with some of the completed assessments performed by their

respective PWSs. EPA developed the examples in this appendix based on the assessment forms

provided by the States. Persona l information about the PWS or any person mentioned in the

example forms is fictitious in nature. They are provided to show the types of information that

are expected to be included in the form.B-2 

### Assessment Form Instructions

1. Fill in system information under the first sectio n of the form. The following information must

be provided at a minimum:

• System Name

• Source Water (GW, SW, GWUDI, Purchased)

• System Type (CWS, NTNCWS, TNCWS)

• Population Served

• Operator in Responsible Charge (ORC)

• Phone

• City, State

• PWSID #

• PWS Address

2. Respond to all Questions 1-10:

• Type “ 3 ” in the box for the items that were review ed and checked or “N/A” if the item is

not applicable to the system.

• Print “Yes” or “No” in th e “Issue(s) found?” column.

• Describe any issues found and corrective action taken.

• Be sure to include dates of any corrective act ions taken.

3. 

### Sign and date form on last page. Form must be completed based on data and documents

available to the PWS operator in charge, mainta ined on file, and sent to the primacy agency

within XX days.B-3 

### Example No. 1 – Level 1 Assessment

UTILITY PROFILE

Buttermilk Falls Country Club is a non-transien t, non-community water system that gets its

water from a ground water source. It collects 1 routine sample per month. The system does not

have any records of past violations.

DESCRIPTION OF THE PROBLEM

In November 2009, the routine monthly sample a nd one of its associated repeat samples came

back positive for total coliforms. This triggered a Level 1 assessment.

ASSESSMENT AND CORRECTIVE ACTION

All applicable items listed in the Level 1 asse ssment form were all ch ecked. Nothing unusual

was found and all of the subsequent repeat samples came back negative.B-4 

## THIS PAGE INTENTION ALLY LEFT BLANKCONCEPT EXAMPLE NO. 1Level 1 Assessment Form

B-5System Name:Buttermilk Falls Country ClubSource Water:Ground WaterPWSID #1234567System Type:NTNCWSPopulation Served:120PWS Address:Operator in Responsible Charge (ORC):J. GriffinPhone:012-345-6789123 Anyway St., Buttermilk Falls, MS 10000City, State:Buttermilk Falls, MSCounty:HooverPerson that collected TC samples if different than ORC:C. Gary, HHH LabsPhone:123-456-7890Address, City, State, Zip:222 Second St., Buttermilk Falls, MS 12121Date Assessment Completed:11/12/2009Questions (1-5)Reviewed andchecked?(Type “3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)1. Have any of the following occurred atrelevant facilities prior to the collectionof TC samples?-any interruptionsin the treatment process-any reported loss of pressure events (5 psi)-operation and maintenance activities that could haveintroduced total coliform-reported vandalism and/or unauthorized access to facilities-visible indicators of unsanitary conditions reported-Has there been a fire fighting event, flushing operation, sheared hydrant, etc.9No2. Have there been any recent operational changes to the system?-sources introduced-treatment oroperational changes-potential sources of contamination9No3. Evaluate sample site.-condition or location of tap-regular use of connection9No4. Sample protocol followed and reviewed.-flush tap-remove aerator-no swivel-fresh sample bottles-sample storage acceptable9No5. Distribution System-system pressure-cross connection-pump station-air relief valves-fire hydrants or blow off-breaks-repairs9NoCONCEPT EXAMPLE NO. 1Level 1 Assessment Form

B-6Questions (1-5)Reviewed andchecked?(Type “3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)6. Storage Tank-screens-security-access opening-condition of tank-vent-drain overflow-pressure tank-O&MN/A7. Treatment Process-interruptions-POE/POU-softeners-O&MN/A8. Source - Well-sanitary seal-vent screened-air gap-cross connection-security-pump to waste line9No9. Source - Spring-condition of spring development-condition of spring box-securityN/A10. Source - Surface Water Supply-heavy rainfall-rapid snowmeltN/ANote: Form to be completed based on dataand documents available to the PWS operatorin charge, maintained on file and returned to the Primacy Agency within XX days.Additional Comments:Atthistime,theobviouscauseofthetotalcoliform‐positiveresultshasnotbeenidentified.Print name of person completing form:Betty SutherlandDate:11-12-09Signature:Reserved for State1.Assessment has been successfully completed.2.Likely reason for total coliform positive- occurrence is established.3.System has corrected the problem.4.Was a reset requested and / or granted? – Rationale5.Name of State reviewer:B-7 

### Example No. 2 – Level 1 Assessment

UTILITY PROFILE

Silver Lake is a mid-sized community water system that supplies treated ground water to

approximately 24,200 people. It collects 25 routine samples per month.

DESCRIPTION OF THE PROBLEM

The system received a notice of violation for fail ing to take all of the required repeat samples

after a total coliform-positive sample was detected, triggering the system to have a Level 1

assessment.

ASSESSMENT AND CORRECTIVE ACTION

Upon thorough inspection of the di stribution system, an air rel ease valve was found submerged

in a flooded valve vault. A permanent sump pu mp will be installed in the vault based on a

schedule approved by the State. Shock chlorina tion measures were performed in accordance

with State guidelines on the portion of the lin e where the air release valve was located.B-8 

## THIS PAGE INTENTION ALLY LEFT BLANKCONCEPT EXAMPLE NO. 2Level 1 Assessment Form

B-9System Name:Silver LakeSource Water:Ground WaterPWSID #2345671System Type:CWSPopulation Served:24,200PWS Address:Operator in Responsible Charge (ORC):J. TroyPhone:012-345-6789123 Anyway St., Silver Lake, MI 10000City, State:Silver Lake, MICounty:HamiltonPerson that collected TC samples if different than ORC:B. Black, CDE LabsPhone:123-456-7890Address, City, State, Zip:111 First St., Gold Water, MI 20000Date Assessment Completed:02/12/2010Questions (1-5)Reviewed andchecked?(Type “3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)1. Have any of the following occurred atrelevant facilities prior to the collectionof TC samples?-any interruptionsin the treatment process-any reported loss of pressure events (5 psi)-operation and maintenance activities that could haveintroduced total coliform-reported vandalism and/or unauthorized access to facilities-visible indicators of unsanitary conditions reported-Has there been a fire fighting event, flushing operation, sheared hydrant, etc.9No2. Have there been any recent operational changes to the system?-sources introduced-treatment oroperational changes-potential sources of contamination9No3. Evaluate sample site.-condition or location of tap-regular use of connection9No4. Sample protocol followed and reviewed.-flush tap-remove aerator-no swivel-fresh sample bottles-sample storage acceptable9No5. Distribution System-system pressure-cross connection-pump station-air relief valves-fire hydrants or blow off-breaks-repairs9YesVisual inspection of distribution systemconducted on 2/11/10 revealed a potentialcontamination source atend of distributionsystem. An air release valve was foundsubmerged in a flooded vault.Sump pump to be installed at potential contamination siteon 2/20/10. State approved corrective action beyond the30-day period. Shock chlorination performed inaccordance with State guidelineson portion of water linewhere air valve is located.CONCEPT EXAMPLE NO. 2Level 1 Assessment Form

B-10Questions (1-5)Reviewed andchecked?(Type “3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)6. Storage Tank-screens-security-access opening-condition of tank-vent-drain overflow-pressure tank-O&M9No7. Treatment Process-interruptions-POE/POU-softeners-O&M9No8. Source - Well-sanitary seal-vent screened-air gap-cross connection-security-pump to waste line9No9. Source - Spring-condition of spring development-condition of spring box-securityN/A10. Source - Surface Water Supply-heavy rainfall-rapid snowmeltN/ANote: Form to be completed based on dataand documents available to the PWS operatorin charge, maintained on file and returned to the Primacy Agency within XX days.Additional Comments:Print name of person completing form:Adam LocklandDate:02-12-2010Signature:Reserved for State1.Assessment has been successfully completed.2.Likely reason for total coliform-positive occurrence is established.3.System has corrected the problem.4.Was a reset requested and / or granted? – Rationale5.Name of State reviewer:B-11 

### Example No. 3 – Level 1 Assessment

UTILITY PROFILE

Eagle Cliff is a community water system that rece ives its water from a spring source and serves

5,500 people. It collects 6 routine samples per month.

DESCRIPTION OF THE PROBLEM

In July 2009, the routine sample and one of its associated rep eat samples both came back total

coliform-positive triggering a Level 1 assessment.

ASSESSMENT AND CORRECTIVE ACTION

Upon inspection of the distribution system piping, small factures were found in the water main

leading from the spring source to a water tank. The piping was replaced and additional samples

were taken to determine whether coliforms were still present in the system. The results came

back negative.B-12 

## THIS PAGE INTENTION ALLY LEFT BLANKCONCEPT EXAMPLE NO. 3Level 1 Assessment Form

B-13System Name:Eagle CliffSource Water:SpringPWSID #3456712System Type:CWSPopulation Served:5,500PWS Address:Operator in Responsible Charge (ORC):F. LangdonPhone:012-345-6789456 Anyway St., Eagle Cliff, AL 10000City, State:Eagle Cliff, ALCounty:HooverPerson that collected TC samples if different than ORC:C. HeartPhone:123-456-7890Address, City, State, Zip:333 Third St., Eagle Cliff, AL 10000Date Assessment Completed:9/1/2009Questions (1-5)Reviewed andchecked?(Type “3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)1. Have any of the following occurred atrelevant facilities prior to the collectionof TC samples?-any interruptionsin the treatment process-any reported loss of pressure events (5 psi)-operation and maintenance activities that could haveintroduced total coliform-reported vandalism and/or unauthorized access to facilities-visible indicators of unsanitary conditions reported-Has there been a fire fighting event, flushing operation, sheared hydrant, etc.9No2. Have there been any recent operational changes to the system?-sources introduced-treatment oroperational changes-potential sources of contamination9No3. Evaluate sample site.-condition or location of tap-regular use of connection9No4. Sample protocol followed and reviewed.-flush tap-remove aerator-no swivel-fresh sample bottles-sample storage acceptable9No5. Distribution System-system pressure-cross connection-pump station-air relief valves-fire hydrants or blow off-breaks-repairs9YesSmall fractures detected in raw water linefrom spring to tank.Raw water line replacement completed on 8/30/2009CONCEPT EXAMPLE NO. 3Level 1 Assessment Form

B-14Questions (1-5)Reviewed andchecked?(Type “3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)6. Storage Tank-screens-security-access opening-condition of tank-vent-drain overflow-pressure tank-O&M9No7. Treatment Process-interruptions-POE/POU-softeners-O&M9No8. Source - Well-sanitary seal-vent screened-air gap-cross connection-security-pump to waste lineN/A9. Source - Spring-condition of spring development-condition of spring box-security9No10. Source - Surface Water Supply-heavy rainfall-rapid snowmeltN/ANote: Form to be completed based on dataand documents available to the PWS operatorin charge, maintained on file and returned to the Primacy Agency within XX days.Additional Comments:Print name of person completing form:Michael TaylorDate:09-01-2009Signature:Reserved for State1.Assessment has been successfully completed.2.Likely reason for total coliform-positive occurrence is established.3.System has corrected the problem.4.Was a reset requested and / or granted? – Rationale5.Name of State reviewer:B-15 

### Example No. 4 – Level 1 Assessment

UTILITY PROFILE

Eggleston Glen is a large muni cipal water system that is su pplied by a ground water source under

the direct influence of surface wa ter (GWUDI). The system treats its water before serving it to

its 985,000 customers. It collects over 300 routine samples per month.

DESCRIPTION OF THE PROBLEM

In August 2009, more than 5% of the monthly total coliform samples came back positive

triggering a Level 1 assessment. Many of the pos itive samples were in the same general location

in the distribution system and in proximity to a large ground storage tank. Several days prior to

the collection of the positive samples, the system experienced pressure loss for a period of 4

hours while the media in the GAC filters at one of the plants was being changed out. During this

time the tank levels dropped to near empty.

ASSESSMENT AND CORRECTIVE ACTION

Normally stagnant water from the tank entered the distribution system during the pressure loss

event causing the total coliform positive results. The tank was taken off-line, cleaned and shock

chlorinated in accordance with State guideline s before putting it back on service. The

distribution system near the tank was al so flushed to improve water turnover.B-16 

## THIS PAGE INTENTION ALLY LEFT BLANKCONCEPT EXAMPLE NO. 4Level 1 Assessment Form

B-17System Name:Eggleston GlenSource Water:GWUDIPWSID #4567123System Type:CWSPopulation Served:985,000PWS Address:Operator in Responsible Charge (ORC):J. GriffinPhone:012-345-6789123 Anyway St., Eggleston Glen, CO 10000City, State:Eggleston Glen, COCounty:HooverPerson that collected TC samples if different than ORC:V. Lewis, GHG LabsPhone:123-456-7890Address, City, State, Zip:444 Fourth St., Littletown, CO 20000Date Assessment Completed:8/28/2009Questions (1-5)Reviewed andchecked?(Type “3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)1. Have any of the following occurred atrelevant facilities prior to the collectionof TC samples?-any interruptionsin the treatment process-any reported loss of pressure events (5 psi)-operation and maintenance activities that could haveintroduced total coliform-reported vandalism and/or unauthorized access to facilities-visible indicators of unsanitary conditions reported-Has there been a fire fighting event, flushing operation, sheared hydrant, etc.9YesLoss of system pressure for 4 hours whilechanging media in GAC filters. Tank leveldropped to near empty. This may haveallowed "old" water to enter the systemfrom system tank.Distribution system flushed on 8/15/2009, especially nearthe tank to improve turnover. Tank was taken off-line,cleaned, and shock chlorinated in accordance with Stateguidelines before putting it back on service. Chlorine willbe checked at sample location at least two times permonth.2. Have there been any recent operational changes to the system?-sources introduced-treatment oroperational changes-potential sources of contamination9No3. Evaluate sample site.-condition or location of tap-regular use of connection9No4. Sample protocol followed and reviewed.-flush tap-remove aerator-no swivel-fresh sample bottles-sample storage acceptable9No5. Distribution System-system pressure-cross connection-pump station-air relief valves-fire hydrants or blow off-breaks-repairs9NoCONCEPT EXAMPLE NO. 4Level 1 Assessment Form

B-18Questions (1-5)Reviewed andchecked?(Type “3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)6. Storage Tank-screens-security-access opening-condition of tank-vent-drain overflow-pressure tank-O&M9No7. Treatment Process-interruptions-POE/POU-softeners-O&M9No8. Source - Well-sanitary seal-vent screened-air gap-cross connection-security-pump to waste line9Yes See item No. 19. Source - Spring-condition of spring development-condition of spring box-security9No10. Source - Surface Water Supply-heavy rainfall-rapid snowmeltN/ANote: Form to be completed based on dataand documents available to the PWS operatorin charge, maintained on file and returned to the Primacy Agency within XX days.Additional Comments:Print name of person completing form:John GilmoreDate:08-28-2009Signature:Reserved for State1.Assessment has been successfully completed.2.Likely reason for total coliform-positive occurrence is established.3.System has corrected the problem.4.Was a reset requested and / or granted? – Rationale5.Name of State reviewer:B-19 

### Example No. 5 – Level 2 Assessment

UTILITY PROFILE

Warsaw Falls is a community water system that gets its water from ground water sources. It

serves a population of 2,550 people and co llects 3 routine samples every month.

DESCRIPTION OF THE PROBLEM

In January 2010, the system had an E

. coli MCL violation (a rou tine sample that was E. coli

positive followed by a repeat sample that was to tal coliform-positive) that triggered a Level 2

assessment.

ASSESSMENT AND CORRECTIVE ACTION

The Level 2 assessment revealed unsanitary c onditions around one partic ular well that was

located in a parking lot, which may or may not have been the source of the contamination. The

system operator noted the need to re-locate or significantly impr ove the well due to its location

and the poor condition of the well casing. The sy stem coordinated with the State to develop

interim measures and to work out a schedule to perform the remaining corrective action beyond

the 30-day period. The pressure ta nk was also recently replaced but was not believed to be the

source of the contamination as the whole syst em was shock chlorinated after the tank was

replaced.B-20 

## THIS PAGE INTENTION ALLY LEFT BLANKCONCEPT EXAMPLE NO. 5Level 2 Assessment Form

B-21System Name:Warsaw Falls Recreation CenterSource Water:Ground WaterPWSID #5671234System Type:CWSPopulation Served:2,550PWS Address:Operator in Responsible Charge (ORC):Peter GarrisonPhone:012-345-6789123 Anyway St., Warsaw Falls, FL 10000City, State:Warsaw Falls, FLCounty:FordPerson that collected TC samples if different than ORC:J. Smith, ABC LabsPhone:123-456-7890Address, City, State, Zip:012 Main St., Bigtown, FL 11111Date Assessment Completed:02/10/2010QuestionsReviewed andchecked?(Type “3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)1. Have any of the following occurred at relevant facilities prior to the collection of TC samples?a.Were there any operation and maintenance activities that could haveintroduced total coliforms?9Nob. Have there been any interruptions in the treatment process?9Noc. Has the system lost pressure to less than 5 psi?9Nod.Have there been any vandalismand/or unauthorized access tofacilities?9Noe. Are there any visible indicators of unsanitary conditions observed?9YesUnsanitary conditions around well includinggarbage and parking lot run-off.See item 8.f.Have there been any analytical results or any additional samplescollected, including source samples which were positive (not forcompliance)?9Nog.Have there been any community illness suspected of beingwaterborne (e.g., Does the communitypublic health official indicatethat an outbreak has occurred.)9Noh.Did the water system receive any TCR monitoring violations in thepast 12 months? If yes, when.9Noi.What was the most recent date on which satisfactory total coliformsamples were taken?Date:Dec 2009j.Have there been a fire fighting event, flushing operation, shearedhydrant, etc.9Nok. Other comments on records and maintenance?None2. Have there been any recenttreatment or operational changes?a.Have any inactive sources recently been introduced into the system(e.g., auxiliary systems)?9NoCONCEPT EXAMPLE NO. 5Level 2 Assessment Form

B-22QuestionsReviewed andchecked?(Type “3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)b. Have there been any new sources introduced into the system?9Noc.Is there evidence of any potential sources of contamination (mainbreaks, low pressure, high turbidity, loss of disinfection, etc.)?9No3. Evaluate sample sitea.What is the condition of the tap?(Provide comments)Goodb.What is the location of the tap?(Provide comments)Goodc.What is the regular use of the connection?(Provide comments)Raw water tap for sample collectiond.Have there been any plumbing changes or construction? If yes,when and what was the repair or change?9Noe. Have there been any plumbing breaks or failure? If yes, when?9Nof.List any identified cross connections after the service connection orin premise plumbing.(Provide comments)Noneg.Were all of the backflow prevention devices present,operational andmaintained?9Noh.Were there any low pressure events or changes in water pressureafter the service connection or in the premise plumbing? If yes,when?9Noi.Is there any treatment devices after the service connection or inpremise?(Circle response, if applicable)Point of Entry (POE) Point of Use (POU)j. Other comments on sample site?None4. Sample protocolfollowed and revieweda.Flush tap, remove aerator, no swivel, fresh sample bottles, samplestorage acceptable9No5. Distribution Systema.System pressure: Is there evidence that the system experienced lowor negative pressure? If yes, when?9Nob. List any identified cross connections.9Noc.Pump station: Are there any sanitary defects in the pump station?Are pump(s) operable?9Nod.Last pump maintenance/service date.(Respond if applicable)Date:12/2006Maintenance Performed?Mechanical seal replacedCONCEPT EXAMPLE NO. 5Level 2 Assessment Form

B-23QuestionsReviewed andchecked?(Type “3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)e.Air relief valves: Is the valve vault subject to flooding or does thevent terminate below grade?9Nof.Fire hydrant/blow off: Are any located in an area with a high watertable or pits?9Nog. Is the distribution system secured to prevent unauthorized access?9Noh.Are the backflow prevention devices at high risk sites present,operational and maintained?9Noi.Have there been any water main repairs or additions? If yes when,and what was the repair or addition?9Noj. Have there been any water main breaks? If yes, when?9Nok.Was there any scheduled flushing of the distribution system? If yes,when?9Nol.Is there any evidence of intentional contamination in the distributionsystem?9Nom. Other comments on the distribution information.None6. Storage Facilitiesa. Are the overflow and vents properly screened?9Nob. Is the facility secured to prevent unauthorized access?9Noc. Does the access opening have the proper gasket and seal tightly?9Nod. Could the physical condition of tank be a source of contamination?9No The pressure tank was recently replaced.Whole system was shock chlorinated after thetank replacement. It is not believed there iscorrelation between the bacteria found and thework on this tank.e.Is the vent turned down and maintaining an approved air gap at thetermination point?9Nof. Does the drain/overflow line terminate at a minimum of 12" air gap?9Nog.If present, is the pressure tankmaintaining an appropriate minimumpressure?9Noh. Has proper O&M been performed?9Noi. Was there any observed physical deterioration of the tank?9Noj. Were there any observed leaks?9Nok.Is there any evidence of intentional contamination at the storagetank?9Nol.Has there been any facility maintenance (i.e. painting/coating)? Ifyes, when?9NoCONCEPT EXAMPLE NO. 5Level 2 Assessment Form

B-24QuestionsReviewed andchecked?(Type “3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)m. Is facility maintenance occurring per appropriate schedule?9Non.Does the tank "float" on the distribution system or are there separateinlet and outlet lines?9Noo.What is the measured chlorine residual (total/free) of the waterexiting the storage tank today?ResidualN/Ap.Are there any unsealed openings in the storage facility such asaccess doors, vents or joints?9Noq. Other comments on the storage systemNone7. Treatment Process. (If applicable)a. Treatment devices operational and maintained?N/Ab. Is there any recent installation or repair of treatment equipment?N/Ac.Were there any recent changes in the treatment process? If yes,when, what was the change?N/Ad.Were there any interruptions of treatment (lapses in chemical feed,turbidity excursions, disinfection)? If yes which part, when and forhow long?N/Ae.What is the free chlorine residual measured immediatelydownstream from the pointof application?Residual:N/Af. Did a review of the filter turbidity profiles reveal any anomalies?N/Ag. Were there any failures to meet the C x T calculations?N/Ah. Were the flow ratesabove the rated capacity?N/Ai. Were there any anomalies on the settled water turbidities?N/Aj. Other comments on the treatment system.None8. Source – Wella. Is the sanitary seal intact?9Nob. Is the vent screened?9Noc. Does the vent and pump to wasteterminate in an approved air gap?9Nod. Are there any unprotected cross connections at the wellhead?9Noe.How is the well used?(Circle if applicable)Primary Backup Emergency Not a PWS Not Drinking WaterCONCEPT EXAMPLE NO. 5Level 2 Assessment Form

B-25QuestionsReviewed andchecked?(Type “3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)f. How far does the casing extend above grade? Height14 inchesComments:g. Is the well cap vented?9Noh. Is there evidence of standing water near the wellhead?9YesAfter heavy rain events, there is standingwater for a day or two.i. Is the wellhead secured to prevent unauthorized access?9Noj.Have there been any sewer spills, source water spills or otherdisturbances?9Nok.Other comments on the well system. (Are there aspects of wellconstruction and operation that would bear on observed positives?)Well needs significant rehabilitation or relocation, requiring more than 30 days. Coordinated with district engineer to developschedule and interim measures. Well will be kept off-line to greatest extent possible, with the State to be notified and chlorinedisinfection to be applied at 2 mg/L whenever well is put on-line. Engineering feasibility study and corrective actionrecommendation and proposed completion schedule due to State by3/10/10. Corrective action and completion schedule approved byState by 3/25/10.9. Source – Springa. What is the condition ofthe spring development?N/Ab. What is the condition of the spring box?N/Ac. Is the spring secured to prevent unauthorized access?N/Ad. Other comments on the spring system.None10. Source - Surface Water Supplya.Have there been any sewer spills, source water spills or otherdisturbances?N/Ab. Have there been any algal blooms?N/Ac. Has source water turnover occurred?N/Ad. Other source water commentsNoneEnvironmental Eventsa. Has there been heavy rainfall?9Yes See Item 8.b. Has there been any rapid snow melt or flooding?9Noc.Have there been changes in available source water (e.g., significantdrop in water table, well levels, reservoir capacity, etc.)9Nod. Have there been any interruptions to electrical power?9Noe. Have there been any extremes in heat or cold?9NoNote : Form to be completed based on data and documents available to the PWS operator in charge, maintained on file and returned to the Primacy Agency within XX days.CONCEPT EXAMPLE NO. 5Level 2 Assessment Form

B-26Additional Comments:Print name of person completing form:Chris WeaverDate:02/03/2010Signature:Reserved for State1. Assessment has been successfullycompleted. Name of State Reviewer:B-27 

### Example No. 6 – Level 2 Assessment

UTILITY PROFILE

Chimney Bluffs Community Church is a transi ent non-community water system that gets its

water from a ground water source. It serves a population of about 200 people and takes a routine

sample every quarter.

DESCRIPTION OF THE PROBLEM

The system had two total coliform-positive sa mples in July 2009 and again in March 2010

triggering a Level 2 assessment (2 Level 1 assess ments within a rolling 12-month period). Since

the system does not have anyone approved by th e State to perform a Level 2 assessment, the

Operator in Responsible Charge (ORC) identified an assessor approved by the State from the

State website.

ASSESSMENT AND CORRECTIVE ACTION

The system noted three possible sources of cont amination: 1) inadequate/improper chlorination

of an in-line conditioner afte r replacement of pressure tank and plumbing; 2) need for

replacement of filters in the reverse osmosis sy stem; and 3) use of a swivel faucet at the

sampling site. The system suspected the first pos sible source as the cause of the contamination

and chlorinated the in-line conditi oner in March 2010. The old swiv el faucet was also replaced.B-28 

## THIS PAGE INTENTION ALLY LEFT BLANKCONCEPT EXAMPLE NO. 6Level 2 Assessment Form

B-29System Name:Chimney Bluffs Community ChurchSource Water:Ground WaterPWSID #6712345System Type:TNCWSPopulation Served:200PWS Address:Operator in Responsible Charge (ORC):Mary SpellingPhone:012-345-6789123 Anyway St., Chimney Bluffs, AZCity, State:Chimney Bluffs, AZ10000County:JacksonPerson that collected TC samples if different than ORC:A. Brown, ABC LabsPhone:123-456-7890Address, City, State, Zip:7556 Desert Ave, Tempe, AZ 99999Date Assessment Completed:04/06/2010QuestionsReviewed andchecked?(Type “3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)1. Have any of the following occurred at relevant facilities prior to the collection of TC samples?a.Were there any operation and maintenance activities that could haveintroduced total coliforms?9YesThe pressure tank and plumbing in andaround the pump room were recentlyreplaced. System includes an in-line waterconditioner. It is unknown if waterconditioner was chlorinated or by-passedduring the chlorination prior to putting tankand plumbing back in service.Water conditioner chlorinated on 3/30/2010 andput back in service.b. Have there been any interruptions in the treatment process?9Noc. Has the system lost pressure to less than 5 psi?9Nod.Have there been any vandalismand/or unauthorized access tofacilities?9Noe. Are there any visible indicators of unsanitary conditions observed?9Nof.Have there been any analytical results or any additional samplescollected, including source samples which were positive (not forcompliance)?9Nog.Have there been any community illness suspected of beingwaterborne (e.g., Does the communitypublic health official indicatethat an outbreak has occurred.)9Noh.Did the water system receive any TCR monitoring violations in thepast 12 months? If yes, when.9Yes July 2009i.What was the most recent date on which satisfactory total coliformsamples were taken?Date:Dec 2009j.Have there been a fire fighting event, flushing operation, shearedhydrant, etc.9Nok. Other comments on records and maintenance?None2. Have there been any recenttreatment or operational changes?CONCEPT EXAMPLE NO. 6Level 2 Assessment Form

B-30QuestionsReviewed andchecked?(Type “3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)a.Have any inactive sources recently been introduced into the system(e.g., auxiliary systems)?9Nob. Have there been any new sources introduced into the system?9Noc.Is there evidence of any potential sources of contamination (mainbreaks, low pressure, high turbidity, loss of disinfection, etc.)?9No3. Evaluate sample sitea.What is the condition of the tap?(Provide comments)Fairb.What is the location of the tap?(Provide comments)church rectoryc.What is the regular use of the connection?(Provide comments)potable water source for the rectoryd.Have there been any plumbing changes or construction? If yes,when and what was the repair or change?9Noe. Have there been any plumbing breaks or failure? If yes, when?9Nof.List any identified cross connections after the service connection orin premise plumbing.(Provide comments)In-line water conditionerg.Were all of the backflow prevention devices present,operational andmaintained?9Noh.Were there any low pressure events or changes in water pressureafter the service connection or in the premise plumbing? If yes,when?9Noi.Is there any treatment devices after the service connection or inpremise?(Circle response, if applicable)Point of Entry (POE) Point of Use (POU)j. Other comments on sample site?None4. Sample protocolfollowed and revieweda.Flush tap, remove aerator, no swivel, fresh sample bottles, samplestorage acceptable9Yes Sample site had old swivel faucet. Faucet replaced on 3/30/10.5. Distribution Systema.System pressure: Is there evidence that the system experienced lowor negative pressure? If yes, when?9Nob. List any identified cross connections.9Noc.Pump station: Are there any sanitary defects in the pump station?Are pump(s) operable?9Nod.Last pump maintenance/service date.(Respond if applicable)Date:N/AMaintenance Performed?CONCEPT EXAMPLE NO. 6Level 2 Assessment Form

B-31QuestionsReviewed andchecked?(Type “3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)e.Air relief valves: Is the valve vault subject to flooding or does thevent terminate below grade?9Nof.Fire hydrant/blow off: Are any located in an area with a high watertable or pits?9Nog. Is the distribution system secured to prevent unauthorized access?9Noh.Are the backflow prevention devices at high risk sites present,operational and maintained?9Noi.Have there been any water main repairs or additions? If yes when,and what was the repair or addition?9Noj. Have there been any water main breaks? If yes, when?9Nok.Was there any scheduled flushing of the distribution system? If yes,when?9Nol.Is there any evidence of intentional contamination in the distributionsystem?9Nom. Other comments on the distribution information.None6. Storage Facilitiesa. Are the overflow and vents properly screened?N/Ab. Is the facility secured to prevent unauthorized access?N/Ac. Does the access opening have the proper gasket and seal tightly?N/Ad. Could the physical condition of tank be a source of contamination?N/Ae.Is the vent turned down and maintaining an approved air gap at thetermination point?N/Af. Does the drain/overflow line terminate at a minimum of 12" air gap?N/Ag.If present, is the pressure tankmaintaining an appropriate minimumpressure?N/Ah. Has proper O&M been performed?N/Ai. Was there any observed physical deterioration of the tank?N/Aj. Were there any observed leaks?N/Ak.Is there any evidence of intentional contamination at the storagetank?N/Al.Has there been any facility maintenance (i.e. painting/coating)? Ifyes, when?N/Am. Is facility maintenance occurring per appropriate schedule?N/ACONCEPT EXAMPLE NO. 6Level 2 Assessment Form

B-32QuestionsReviewed andchecked?(Type “3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)n.Does the tank "float" on the distribution system or are there separateinlet and outlet lines?N/Ao.What is the measured chlorine residual (total/free) of the waterexiting the storage tank today?ResidualN/Ap.Are there any unsealed openings in the storage facility such asaccess doors, vents or joints?N/Aq. Other comments on the storage systemNone7. Treatment Process. (If applicable)a. Treatment devices operational and maintained?9Nob. Is there any recent installation or repair of treatment equipment?9YesThe filters were replaced in the reverseosmosis system that feeds the faucetsconnected to the rectory and the kitchen.Filter replacement has never been the source ofcontamination in the past and is not believe tobe related to this event.c.Were there any recent changes in the treatment process? If yes,when, what was the change?9Nod.Were there any interruptions of treatment (lapses in chemical feed,turbidity excursions, disinfection)? If yes which part, when and forhow long?9Noe.What is the free chlorine residual measured immediatelydownstream from the pointof application?Residual:N/Af. Did a review of the filter turbidity profiles reveal any anomalies?N/Ag. Were there any failures to meet the C x T calculations?N/Ah. Were the flow ratesabove the rated capacity?N/Ai. Were there any anomalies on the settled water turbidities?N/Aj. Other comments on the treatment system.None8. Source – Wella. Is the sanitary seal intact?9Nob. Is the vent screened?9Noc. Does the vent and pump to wasteterminate in an approved air gap?9Nod. Are there any unprotected cross connections at the wellhead?9Noe.How is the well used?(Circle if applicable)Primary Backup Emergency Not a PWS Not Drinking Waterf. How far does the casing extend abovegrade? Height ____________ Comments:CONCEPT EXAMPLE NO. 6Level 2 Assessment Form

B-33QuestionsReviewed andchecked?(Type “3” ifcompleted or“N/A”)Issue(s)found?(Y/N)Issue Description Corrective Action Taken (Including Date)g. Is the well cap vented?9Noh. Is there evidence of standing water near the wellhead?9Noi. Is the wellhead secured to prevent unauthorized access?9Noj.Have there been any sewer spills, source water spills or otherdisturbances?9Nok.Other comments on the well system. (Are there aspects of wellconstruction and operation that would bear on observed positives?)None9. Source – Springa. What is the condition ofthe spring development?N/Ab. What is the condition of the spring box?N/Ac. Is the spring secured to prevent unauthorized access?N/Ad. Other comments on the spring system.None10. Source - Surface Water Supplya.Have there been any sewer spills, source water spills or otherdisturbances?N/Ab. Have there been any algal blooms?N/Ac. Has source water turnover occurred?N/Ad. Other source water commentsNoneEnvironmental Eventsa. Has there been heavy rainfall?9Nob. Has there been any rapid snow melt or flooding?9Noc.Have there been changes in available source water (e.g., significantdrop in water table, well levels, reservoir capacity, etc.)9Nod. Have there been any interruptions to electrical power?9Noe. Have there been any extremes in heat or cold?9NoNote : Form to be completed based on data and documents available to the PWS operator in charge, maintained on file and returned to the Primacy Agency within XX days.Additional Comments:CONCEPT EXAMPLE NO. 6Level 2 Assessment Form

B-34Print name of person completing form:John MarshallDate:04/08/2010Signature:Reserved for State1. Assessment has been successfullycompleted. Name of State Reviewer:C-1 

### Appendix C

Common Sanitary Defects and Corrective Actions

Appendix C presents a summary of the causes of total coliform- / E. coli- positive (TC+/EC+)

results that have been frequently found in the past and the corresponding co rrective action(s) that

systems can take to correct the problem. It is intended to give conc ise guidance in a look-up

table format that PWSs can easily refer to in the event that they are triggered to have an

assessment and perform corrective action. Some of the materials in the following table are

discussed in more detail in Ch apter 4 of this document.

The list is by no means comprehensive or e xhaustive and does not include investigation,

operation and maintenance, or co rrective action guidance particular to each State. Systems

should be aware of State guidelines and c onsult with the Stat e as necessary.

The list of sanitary defects is based on the common causes of TC+/EC+ reported by States and

PWSs. EPA is interested in hearing from the pub lic on other possible causes of TC+ and

EC+ they want to see add ress in this guidance manual.C-2 

## THIS PAGE INTENTION ALLY LEFT BLANKC-3Sanitary Defects /Cause(s) of TC+ andEC+Conditions That May Point to Causeof TC+/EC+Possible Corrective Action(s) For Additional InformationBiofilms•Taste and odor complaints•Colored or turbid water that takes along time to clear•Elevated heterotrophic plate count(HPC) bacteria levels•Numerous isolates with similargenotypic profile•Conduct unidirectional flushing toremove biofilm and sediments fromdistribution system.•Maintain adequate pressure insystem to prevent sloughing ofbiofilm by installing booster pumpstations, variable frequency drives,elevated storage facilities, surgerelief valves, and surge tanks, andmodifying high service pumps.Install automatic pressuremonitoring and control.•Replace/rehabilitate pipe wherebiofilm sloughing is occurring.•Maintain disinfectant residuals inthe distribution system.•Apply temporary disinfection,shock chlorination, and/or boosterdisinfection, in accordance withState guidelines.•Manage water age by looping deadends; increasing volume turnover;and/or installing appropriate mainsizes, automated flushing devices,or mixing devices.•Water ResearchFoundation,Strategies forManaging Total Coliformand E. Coli in DistributionSystems, 2009.•Water ResearchFoundation,FactorsLimiting Microbial Growthin Distribution Systems:Laboratory and Pilot ScaleExperiments, 1996.•Water ResearchFoundation,Assessing andControlling Regrowth inDistribution Systems, 1990.•Water ResearchFoundation,FactorsAffecting Microbial Growthin Model DistributionSystems, 2000.•Camper, A. K.et al.,“Effect of DistributionSystem Materials onBacterial Regrowth.”Journal AWWA , Vol. 95Iss. 7, July 2003, Page(s)107-121.Contamination of waterduring main installation,repair, or rehabilitation•Break/repair activities that couldhave allowed entry of contaminantsor dislodged accumulated pipedebris into bulk water•Pressure loss associated with break•Flush system (spot or routine).•Apply temporary disinfection,shock chlorination, and/or boosterdisinfection in accordance withState guidelines.•AWWA C651 (Standardfor Disinfecting WaterMains)C-4Sanitary Defects /Cause(s) of TC+ andEC+Conditions That May Point to Causeof TC+/EC+Possible Corrective Action(s) For Additional Information•Low disinfectant residual•Colored or turbid water•Review/enhance existingprocedures for main installation,repair, or rehabilitation procedures.•Maintain adequate pressure in thesystem by installing booster pumpstations, variable frequency drives,elevated storage facilities, surgerelief valves, and surge tanks, andmodifying high service pumps.Install automatic pressuremonitoring and control.Cross-connections•Pressure loss event within a portionof the distribution system•Total coliform-positive samplesoccur at high elevation and/or lowpressure location(s)•Presence of a high-risk customerfor backflow (e.g., industrial user)•Eliminate cross-connection.•Implement cross-connectioncontrol and backflow prevention(CCBFP) program.•Install backflow preventionassemblies and devices.•Flush system (spot or routine).•Apply temporary disinfection,shock chlorination, and/or boosterdisinfection in accordance withState guidelines.•Maintain adequate pressure insystem to prevent backflow andbacksiphonage by installing boosterpump stations, variable frequencydrives, elevated storage facilities,surge relief valves, and surge tanks,and modifying high service pumps.Install automatic pressuremonitoring and control.•Cross-Connection ControlManual, EPA 816-R-03-002, EPA, February 2003Errors in the samplingprotocol (i.e., proper•Changes in sampler or protocol•Review current protocol and ifinadequate, identify alternate•Water ResearchFoundation,SampleC-5Sanitary Defects /Cause(s) of TC+ andEC+Conditions That May Point to Causeof TC+/EC+Possible Corrective Action(s) For Additional Informationsampling protocols werenot followed – e.g., tapwas not flushed, aeratorwas not removed, etc.)protocol.•Enhance training on sitepreparation, flushing protocols, andsanitary sample collection andtransport procedures.•Sanitize sample coolers and icepacks. Ensure that samples areshipped properly and securely (e.g.,bottles do not tip or becomecontaminated during transport).Collection Procedures andLocations for BacterialCompliance Monitoring,2004•Interactive Sampling Guidefor Drinking Water SystemOperators CD, available at:http://www.epa.gov/ncepihom/Inadequacies of the samplesite (e.g., unsanitaryconditions, leaks andbreaches, unprotectedaccess, improperconstruction, improperlocation)•Changes in sampling site use•Presence of unsanitary conditionsat the sampling site•Develop a sample siting plan that isrepresentative of the water qualityin the distribution system.•Install dedicated sampling taps.•Correct leaks or other sitedeficiencies and breaches.•Sanitize or replace sampling site.•Water ResearchFoundation,SampleCollection Procedures andLocations for BacterialCompliance Monitoring,2004•Interactive Sampling Guidefor Drinking Water SystemOperators CD, available at:http://www.epa.gov/ncepihom/Inadequate disinfectantresidual levels in thedistribution system•Variable raw and/or treated waterquality conditions•Inadequate disinfectant at entrypoint•Inadequate disinfectant at boosterstations•Interruptions in disinfectionprocesses•Increases in temperature that leadto accelerated disinfectant decay•Apply temporary disinfection,shock chlorination, and/or boosterdisinfection in accordance withState guidelines.•Manage water age by looping deadends; increasing volume turnover;and/or installing appropriate mainsizes, automated flushing devices,or mixing devices.•Install/upgrade on-line water•AWWA G200 (Standardfor Distribution SystemsOperation andManagement)C-6Sanitary Defects /Cause(s) of TC+ andEC+Conditions That May Point to Causeof TC+/EC+Possible Corrective Action(s) For Additional Informationquality monitoring and control.•Flush system (spot or routine).Intrusion through pipeleaks, pipeline fracturecracks, leaking joints,submerged air-vacuum/air-release valves, anddeteriorating seals•Pressure loss or reduction in aportion of the distribution system•Presence of leaks, cracks and otherentry points•High groundwater table and/orpresence of sewers near thesusceptible water main•Numerous isolates with uniquegenotypic profile•Repair/replace leaky component.•Maintain adequate pressure insystem by installing booster pumpstations, variable frequency drives,elevated storage facilities, surgerelief valves, and surge tanks, andmodifying high service pumps.Install automatic pressuremonitoring and control.•Water ResearchFoundation,Verificationand Control of PressureTransients and Intrusion inDistribution Systems, 2004.Pressure loss (can resultfrom events such asflushing, main breaks,power outages, fires, orimproper operations andmanagement (O&M)practices)•Recent maintenance activities,main breaks, power outages, fires•Turbidity increase or fluctuations•Flush distribution system (spot orroutine).•Apply temporary disinfection,shock chlorination, and/or boosterdisinfection in accordance withState guidelines.•Improve O&M practices.•Maintain adequate pressure byinstalling booster pump stations,variable frequency drives, elevatedstorage facilities, surge reliefvalves, and surge tanks, andmodifying high service pumps.•Install automatic pressuremonitoring and control.•AWWA C651 (Standardfor Disinfecting WaterMains)•AWWA G200 (Standardfor Distribution SystemsOperation andManagement)Sediment build-up instorage tank or reservoir•Increased disinfectant demands•Increase in turbidity, particularly inwater samples collected when tankis draining•Elevated HPC in samples from tankor reservoir•Low disinfectant residual in•Drain and flush tank or reservoir.•Shock chlorination of tank orreservoir in accordance with Stateguidelines.•AWWA C652(Disinfection of WaterStorage Facilities)C-7Sanitary Defects /Cause(s) of TC+ andEC+Conditions That May Point to Causeof TC+/EC+Possible Corrective Action(s) For Additional Informationsamples from tank or reservoirStorage tank physicaldeficiencies like holes,inadequate screening, etc.(can allow entry of birds,animals, insects, and othervectors that can fecallycontaminate the water)•Presence of physical deficiencies•Recent work on or near the tank•Recent vandalism, storm events, orother events that could impact tankintegrity•Repair broken parts of storage tanklike the vent and hatch.•Repair / install screens.•Install / improve security measures.•AWWA C652(Disinfection of WaterStorage Facilities)Contamination duringflushing/firefightingactivities•Turbidity increase or fluctuations•Color increase or fluctuations•Pressure fluctuations•Ensure unidirectional flushingapproach is used for flushingprogram and that water qualityobjectives (i.e., chlorine, turbidity,and iron) are met prior toterminating flushing.•Water ResearchFoundation,Implementation andOptimization ofDistribution FlushingPrograms, 1992•Water ResearchFoundation,Deteriorationof Water Quality inDistribution Systems, 1987•Water ResearchFoundation,Developmentof Distribution SystemWater Quality OptimizationPlans,2005Treatment breakthrough•Variable raw and/or treated waterquality conditions•Inadequate disinfectant at entrypoint•Elevated HPC bacteria levels occurthroughout the distribution system•Increase disinfectant residual.Apply temporary disinfection,shock chlorination, and/or boosterdisinfection in accordance withState guidelines.•Flush system (spot or routine).•Assess performance of treatmentprocesses and remedy cause ofcoliform breakthrough (e.g.,•Small Systems Guide toSafe Drinking Water ActRegulations, EPA 2003:http://www.epa.gov/safewater/C-8Sanitary Defects /Cause(s) of TC+ andEC+Conditions That May Point to Causeof TC+/EC+Possible Corrective Action(s) For Additional Informationreplace filter, decrease particleloading, etc.).Vandalism and/orunauthorized access tofacilities•Recent work or other events at adistribution system facility•Presence of broken or disabledsecurity equipment•Flush system (spot or routine).•Install / improve security measures(e.g., install a fence, lock buildings,install alarms and cameras)•Develop and implement anoperations plan.•Develop standard operatingprocedures (SOPs).•Develop emergency response plan.•AWWA G200 (Standardfor Distribution SystemsOperation andManagement)•Water ResearchFoundation,DistributionSystem Security Primer forWater Utilities, 2005.D-1 

### Appendix D

Industry Standards for Operating a Public Water System

The American Water Works Association (A WWA) has developed standards based on the

collective knowledge of its member ship. The information contained in these standards has been

collected and improved over many years and has gone through rigorous review and development.

AWWA Standards are typically minimum best pract ices and help to ensu re that a product (e.g.,

pipes, fittings, meters, etc.) or a process (e.g., ma in flushing, main installation, etc.) described in

a standard will provide satisfactory service.

Although not a complete list, the following AWWA Standards may be useful as a reference

when implementing the corrective action(s) disc ussed in the RTCR Assessments and Corrective

Actions Guidance Manual and its appendices.D-2 

## THIS PAGE INTENTION ALLY LEFT BLANKD-3 

### Standard Number Topic

AWWA A100 Water Wells

AWWA B300 Hypochlorites

AWWA B301 Liquid Chlorine

AWWA C104/A21.4 Cement-Mortar Lining for Ductile-Iron Pipe and Fittings for Water

AWWA C110/A21.10 Ductile-Iron and Gray-Iron Fittings for Water

AWWA C111/A21.11 Rubber-Gasket Joints for Ductile-Iron Pr essure Pipe and Fittings

AWWA C115/A21.15 Flanged Ductile-Iron Pipe with Du ctile-Iron or Gray-Iron Threaded

Flanges

AWWA C116/A21.16 Protective Fusion-Bonded Epoxy Coatings for the Interior and Exterior

Surfaces of Ductile-Iron and Gray -Iron Fittings for Water Supply

Service

AWWA C150/A21.50 Thickness Design of Ductile-Iron Pipe-Erratum: 02/2003

AWWA C151/A21.51 Ductile-Iron Pipe, Cent rifugally Cast, for Water- Erratum

AWWA C153/A21.53 Ductile-Iron Comp act Fittings, for Water Service

AWWA C200 Steel Water Pipe - 6 in. (150 mm) and Larger

AWWA C203 Coal-Tar Protective Coatings and Linings for Steel Water Pipelines -

Enamel and Tape - Hot Applied

AWWA C205 Cement-Mortar Protective Lining and Coating for Steel Water Pipe - 4

in. (100 mm) and Larger - Shop Applied

AWWA C206 Field Welding of Steel Water Pipe

AWWA C207 Steel Pipe Flanges for Waterworks Service - Sizes 4 in. Through 144 in.

(100 mm Through 3,600 mm)

AWWA C208 Dimensions for Fabricat ed Steel Water Pipe Fittings

AWWA C209 Cold-Applied Tape Coatings for th e Exterior of Special Sections,

Connections, and Fittings for Steel Water Pipelines

AWWA C210 Liquid-Epoxy Coating Systems for the Interior and Exterior of Steel

Water Pipelines

AWWA C213 Fusion-Bonded Epoxy Coating for the In terior and Exterior of Steel

Water Pipelines

AWWA C214 Tape Coating Systems for th e Exterior of Steel Water Pipelines

AWWA C215 Extruded Polyolefin Coatings for the Exterior of Steel Water Pipelines

AWWA C216 Heat-Shrinkable Cross-Linked Polyolef in Coatings for the Exterior of

Special Sections, Connections, and F ittings for Steel Water Pipelines

AWWA C217 Petrolatum and Petroleum Wax Tape Coatings for the Exterior of

Connections and Fittings for Steel Water Pipelines

AWWA C218 Coating the Exterior of Above ground Steel Water Pipelines and

Fittings-Third Edition

AWWA C222 Polyurethane Coatings for the Interior and Exterior of Steel Water Pipe

and Fittings-First Edition

AWWA C224 Two-Layer Nylon-11-Based Polyamide Coating System for the Interior

and Exterior of Steel Water Pipe, Connecctions, Fittings, and Special

SectionsD-4 

### Standard Number Topic

AWWA C225 Fused Polyolefin Coating systems for the Exterior of Steel Water

Pipelines-First Edition

AWWA C300 Reinforced Concrete Pr essure Pipe, Steel-Cylinder Type

AWWA C301 Prestressed Concrete Pressure Pi pe, Steel-Cylinder Type-Erratum -

January 2000

AWWA C302 Reinforced Concrete Pr essure Pipe, Noncylinder Type

AWWA C303 Concrete Pressure Pipe , Bar-Wrapped, Steel-Cylinder Type

AWWA C304 Design of Prestre ssed Concrete Cylinder Pipe

AWWA C400 Asbestos-Cement Pressure Pipe, 4 in. Through 16 in. (100 mm Through

400 mm), for Water Distribution Systems

AWWA C401 The Selection of Asbestos-Cement Pressure Pipe, 4 in. Through 16

in.(100 mm Through 400 mm), for Water Distribution Systems

AWWA C402 Asbestos-Cement Transmission Pi pe, 18 in. Through 42 in. (450 mm

Through 1,050 mm), for Water Supply Service

AWWA C403 Selection of Asbestos-Cement Tran smission Pipe, Sizes 18 in. Through

42 in. (450 mm Through 1,050 mm), for Water Supply Service

AWWA C500 Metal-Seated Gate Valves for Water Supply Service

AWWA C502 Dry-Barre l Fire Hydrants

AWWA C503 Wet-Barre l Fire Hydrants

AWWA C508 Swing-Check Valves for Waterworks Service, 2-in. Through 24-in. (50-

mm Through 600-mm) NPS

AWWA C509 Resilient-Seated Gate Valves for Water Supply Service

AWWA C512 Air Release, Air/ Vacuum, and Comb ination Air Valves for Waterworks

Service

AWWA C515 Reduced-Wall, Resilient-Seated Gate Valves for Water Supply ServiceSecond Edition

AWWA C600 Installation of Ductile-Iron Water Mains and Their Appurtenances

AWWA C602 Cement-Mortar Lining of Water Pipelin es in Place - 4 in. (100 mm) and

Larger

AWWA C605 Underground Installation of Polyvinyl Chloride (PVC) Pressure Pipe

and Fittings for Water-First Edition

AWWA C606 Grooved and Shouldered Joints

AWWA C651 Disinfecting Water Mains

AWWA C652 Disinfection of Water-Storage Facilities

AWWA C653 Disinfection of Water Treatment Plants

AWWA C654 Disinfection of Wells

AWWA C700 Cold-Water Meters - Di splacement Type, Bronze Main Case

AWWA C701 Cold-Water Meters - Tu rbine Type, for Customer Service

AWWA C702 Cold-Water Meters - Compound Type

AWWA C703 Cold-Water Meters - Fire Service Type

AWWA C704 Propeller-Type Meters for Waterworks ApplicationsD-5 

### Standard Number Topic

AWWA C706 Direct-Reading, Remote-Registr ation Systems for Cold-Water Meters

AWWA C707 Encoder-Type Remote-Registration Systems for Cold-Water Meters

AWWA C708 Cold-Water Meters - Multijet Type

AWWA C710 Cold-Water Meters - Disp lacement Type, Plastic Main Case

AWWA C712 Cold-Water Meters - Singlejet Type-First Edition

AWWA C713 Cold-Water Meters Fluidi c-Oscillator Type-First Edition

AWWA C800 Underground Service Line Valves and Fittings

AWWA C900 Polyvinyl Chloride (PVC) Pressure Pi pe and Fabricated Fittings, 4 in.

Through 12 in.(100 mm Through 300 mm ), for Water Distribution

AWWA C901 Polyethylene (PE) Pressure Pipe and Tubing, 1/2 in. (13 mm) Through 3

in. (76 mm), for Water Service

AWWA C903 Polyethylene-Aluminum-Polyethylen e & Cross-linked PolyethyleneAluminum-Cross-linked Polyethylene Composite Pressure Pipes, 1/2 In.

(12 mm) Through 2 In. (50 mm), for Water Service

AWWA C905 Polyvinyl Chloride (PVC) Pressure Pipe and Fabricated Fittings, 14

Inches Through 48 Inches (350m m Through 1,200mm), for Water

Transmission and Distribution

AWWA C906 Polyethylene (PE) Pressure Pipe and Fittings, 4 in. (100 mm) Through

63 in. (1,575 mm), for Water Distribution and Transmission

AWWA C907 Injection-Molded Polyvinyl Chloride (PVC) Pressure Fittings, 4 In.

Through 12 In. (100 mm Through 300 mm ), for Water Distribution

AWWA C909 Molecularly Oriented Polyvinyl Chlo ride (PVCO) Pressure Pipe, 4 in.

Through 12 in. (100 mm Through 600 mm ), for Water Distribution

AWWA C950 Fiberglass Pressure Pipe

AWWA D100 Welded Steel Tanks for Water Storage

AWWA D102 Coating Stee l Water-Storage Tanks

AWWA D103 Factory-Coated Bolted Steel Tanks for Water Storage

AWWA D104 Automatically Controlled, Impresse d-Current Cathodic Protection for

the Interior of Steel Water Tanks

AWWA D110 Wire- and Strand- Wound, Circular, Prestressed Concrete Water Tanks

AWWA D115 Circular Prestressed Concrete Wa ter Tanks with Circumferential

Tendons-First Edition

AWWA D130 Flexible-Membrane Material s for Potable Water Applications

AWWA G100 Water Treatment Plant Oper ation and Management-First Edition

AWWA G200 Distribution System s Operation and Management