Printed on Recycled Paper

United States

Environmental Protection

Agency

Office of Water

4607

EPA 815-R-01-023

October 2001

Reference Guide for 

the Unregulated

Contaminant Monitoring

Regulation

UCMR Reference Guide October 2001

i

Foreword

Under §1445(a)(2)(A) of the Safe Drinking Water Act (SDWA), as amended in 1996, the

Environmental Protection Agency (EPA) is required to establish criteria for a program to monitor

unregulated contaminants and to publish a list of contaminants to be monitored. In response to this

requirement, EPA published the revisions to the Unregulated Contaminant Monitoring Regulation

(UCMR) for public water systems (PWSs) on September 17, 1999 (64 FR 50556), and in

supplemental rules, including the Perchlorate and Acetochlor Rule (March 2, 2000 - 65 FR 11372),

and the List 2 Rule (January 11, 2001 - 66 FR 2273). EPA expects to publish other rules detailing

minormodificationsto the UCMRprogram and List 3 monitoring requirements and analytical methods,

as needed. 

This document was designed to provide anoverview ofthe revised UCMR. It is intended to integrate

the most essential elements of the UCMR, and to provide a reference guide to the UCMR guidance

documents and UCMR rules published by EPA. This document briefly describes the three-tiered

monitoring approach to the UCMR, monitoring schedules, reporting requirements, and the roles and

responsibilities ofStates,EPARegions, and PWSsinUCMRimplementation. Note that this document

does notexplainall UCMRProgramrequirements in detail. Where more detailed and comprehensive

information is available through other EPA guidance documents, the reader is referred to these

documents.
UCMR Reference Guide October 2001

ii
UCMR Reference Guide October 2001

iii

Acknowledgments

This document was prepared in support of the Unregulated Contaminant Monitoring Regulation

(UCMR) for EPA’s Office of Ground Water and Drinking Water. Charles Job served as EPA’s

team leader for development of the UCMR with James Taft as Targeting and Analysis Branch

Chief. Rachel Sakata and Phyllis Branson served as Work Assignment Managers. The UCMR

Work Group provided technical guidance throughout. External expert reviewers and many

stakeholders provided valuable advice to improve the UCMR and this document. The Cadmus

Group, Inc., served as the prime contractor for developing this document. 
UCMR Reference Guide October 2001

iv
UCMR Reference Guide October 2001

v

Table of Contents

Foreword .................................................................... i

Acknowledgments ............................................................. iii

1. Introduction ................................................................ 1

1.1 Purpose and Background .................................................. 1

1.2 Overview of the UCMR Program ........................................... 2

2. Affected Entities and Their Responsibilities ...................................... 13

2.1 Large Public Water Systems .............................................. 13

2.1.1 Assessment Monitoring .............................................. 13

2.1.2 Screening Surveys ................................................. 13

2.1.3 Pre-Screen Testing ................................................. 14

2.2 Small Public Water Systems .............................................. 14

2.2.1 Assessment Monitoring .............................................. 14

2.2.2 Screening Surveys ................................................. 15

2.2.3 Pre-Screen Testing ................................................. 16

2.3 Index Systems ......................................................... 16

2.4 State and Tribal Participation ............................................. 17

3. Contaminants to be Monitored ................................................. 19

3.1 Assessment Monitoring .................................................. 19

3.2 Screening Surveys ...................................................... 19

3.3 Pre-Screen Testing ...................................................... 20

3.4 Water Quality Parameters ................................................ 20

4. Sample Collection and Analysis for UCMR (1999) Contaminants ..................... 23

4.1 Large Public Water Systems .............................................. 23

4.2 Small Public Water Systems .............................................. 23

5. General Monitoring Requirements .............................................. 25

5.1 Monitoring Frequency and Sampling Location ................................ 25

5.2 General Quality Control Requirements ...................................... 27

5.3 Quality Control Requirements for Sample Collection ........................... 32

5.3.1 Quality Control Requirements for Sample Collection: 

Additional Requirements Specific to Large Systems ......................... 32

5.3.2 Quality Control Requirements for Sample Collection: 

Additional Requirements Specific to Small Systems ......................... 33

5.3.3 Quality Control Requirements for Laboratories ........................... 34

5.3.4 Additional Quality Controls .......................................... 34

6. UCMR Reporting Requirements ............................................... 35

6.1 Data Elements ......................................................... 35

6.2 Electronic Reporting and Data Review ...................................... 38

6.3 Public Notification ..................................................... 39

7. State Responsibilities ....................................................... 41

7.1 State Plan Development .................................................. 41
UCMR Reference Guide October 2001

vi

7.2 Partnership Agreements .................................................. 41

7.3 State Waivers for Contaminants Monitored at Large Systems ..................... 42

7.4 Governors’ Petition to Add Contaminants to the Monitoring List .................. 42

8. Participation of Tribal Public Water Systems ..................................... 43

8.1 Tribal Monitoring Plan Development ....................................... 43

8.2 Sample Collection Responsibility .......................................... 43

9. EPA Responsibilities ........................................................ 45

9.1 Partnership Agreements and State Monitoring Plan Development .................. 45

9.2 Sample Collection and Analysis ........................................... 45

9.3 Reviewing Analytical Results and Reporting Requirements ...................... 45

10. Contact Information ........................................................ 47

APPENDICES

Appendix A — Acronym List .............................................. A - 1

Appendix B — Definitions ................................................. B - 1

Appendix C — Number of Small Systems in Representative Sample, by State ......... C - 1

List of Figures

Figure 1. Unregulated Contaminant Monitoring Approach ............................... 7

Figure 2. UCMR (1999) Implementation Timeline and Related Activities .................. 8

List of Tables

Table 1. UCMR (1999) List 1 Contaminants ......................................... 3

Table 2. UCMR (1999) List 2 Contaminants ......................................... 4

Table 3. UCMR (1999) List 3 Contaminants ......................................... 5

Table 4. Total Number of Small Systems in National Representative Sample to 

Conduct Assessment Monitoring (by Size, Type, and Water Source) ................ 15

Table 5. Water Quality Parameters to be Monitored with 

UCMR Microbiological Contaminants ...................................... 20

Table 6. Monitoring Frequency by Contaminant and Water Source Types .................. 26

Table 7. Unregulated Contaminant Monitoring Regulation (1999) List 1 ................... 27

Table 8. Unregulated Contaminant Monitoring Regulation (1999) List 2 ................... 30

Table 9. UCMR Reporting Requirements .......................................... 35
UCMR Reference Guide October 2001

1

1. Introduction

1.1 Purpose and Background

The requirement to monitor unregulated contaminants was established bythe 1986 Amendmentsto the

Safe Drinking Water Act (SDWA). Public water systems (PWSs) were required to report the

monitoring resultsfor up to 48 unregulated contaminants to the States or primacy agencyunderseveral

regulations (40 CFR 141.40(e), (j), and (n)(11) - (12)). Systems with less than 150 service

connections were exempt, provided those systems made their facilities available for the States to

monitor. 

Under §1445(a)(2)(A) ofthe SDWA, as amended in1996, the United States Environmental Protection

Agency (EPA) was required to establish criteria for a program to monitor for unregulated

contaminants and to publish a list of contaminants to be monitored. To fulfill the requirements of the

SDWA,EPApublished theRevisions to the UnregulatedContaminantMonitoringRegulation(UCMR)

for PWSs on September 17, 1999 (64 FR 50556). This regulation included programmatic changes to

the UCMR and provided a list of contaminants for which monitoring was required, or would be

required inthe future. The UCMR set up a three-tiered approach to monitoring for contaminants based

on the availability of analytical methods and insights on contaminant properties, as well as fate and

transport. In response to public comments, and as relevant analytical methods were refined and

developed, EPA published the Perchlorate and AcetochlorRule onMarch2, 2000 (65 FR 11372) and

the List2Rule onJanuary11, 2001 (66 FR 2273). As EPA continues to refine and develop additional

methods and/or identify minor clarifications or modifications needed for the successful

implementation ofthe UCMR, the Agencywill provide additional guidance documents or fact sheets

and will promulgate additional rules, as necessary. 

The UCMRprogramwas developed in coordination with the Candidate Contaminant List(CCL) and

the National Drinking Water Contaminant Occurrence Database (NCOD). The UCMR and the CCL

operate on a 5-year cycle to assess the impact of new and emerging drinkingwater contaminants. The

revised UCMR program is a cornerstone of the sound science approach to future drinking water

regulation. The data collected through the UCMR programwill be stored in the NCOD to facilitate

analysis or review of contaminant occurrence, to guide the development of subsequent CCLs, and to

support the Administrator’s determination of whether or not to regulate a contaminant in the interest

of protecting public health.

The SDWA provisions and EPA regulations which are described in this document contain legally

binding requirements. This document does not substitute for those provisions or regulations, nor is

it a regulationitself. It does not impose legally-binding requirements on EPA, States, or the regulated

community, and may not apply to a particular situation based upon the circumstances. EPA and State

decisionmakers retain the discretionto adoptapproaches on a case-by-case basis that differ fromthis

guidance where appropriate. Any decisions regarding a particular facility will be made based on the

applicable statutes and regulations. Therefore, interested parties are free to raise questions and

objections about the appropriateness of the application ofthis guidance to a particular situation, and

EPA will consider whether or not the recommendations or interpretations in the guidance are

appropriate in that situation based on the law and regulations. EPA may change this guidance in the

futurewithout notice or an opportunity for comment. Mention of trade names or commercial products

does not constitute endorsement or recommendation for use.
UCMR Reference Guide October 2001

2

1.2 Overview of the UCMR Program

EPA regulates many drinking water contaminants which are known to pose a risk to human health.

There are, however, many other potential contaminants which are not currently regulated because of

a lack of information regarding contaminant occurrence or potential health effects of such

contaminants. Further, there are many new, emerging, or reemerging contaminants that may also need

to be evaluated for their occurrence in drinking water. To address the lack of information on the

occurrence of some of these contaminants, in 1999, EPA promulgated the new UCMR program (40

CFR§§141.35, 141.40, and 142.15(c)(3)),replacing the previous unregulated contaminant monitoring

regulation. In addition, EPA published a Direct Final Rule in the January 8, 1999 Federal Register

(64 FR 1493) that suspended the third round of the existing unregulated contaminant monitoring

program for small PWSs (systems serving less than or equal to 10,000 persons). However, large

PWSs (systems serving more than 10,000 persons) were still required to monitor under 40 CFR

§§141.35 and 141.40 for the existing unregulated contaminant monitoring programthrough January 1,

2001, completing their latest round of that monitoring. 

EPA evaluated the availability of analytical methods published by EPA and voluntary consensus

standard organizations such as the American Society for Testing and Materials (ASTM), the

Association of Official Analytical Chemists (AOAC), and the American Public Health Association

(APHA) for all of the unregulated contaminants considered for the UCMR. Based on the availability

of analytical methodsfor each unregulated contaminant, EPAdeveloped a tieredmonitoring approach

comprised of three distinct components.

The first component of the UCMR is Assessment Monitoring, which will be conducted by all of the

approximately 2,800 large communitywatersystems (CWSs) and non-transient non-communitywater

systems (NTNCWSs)serving more than 10,000 persons, and by a statistically representative sample

of 800 small CWSs and NTNCWSs serving 10,000 or fewer persons (except those systems that

purchase all of their water from another PWS). Assessment Monitoring will be conducted for the

UCMR (1999) List 1 contaminants, where analytical methods have already been developed and

refined. Table 1 lists the contaminants to be monitored, and their environmental sources.
UCMR Reference Guide October 2001

3

Table 1. UCMR (1999) List 1 Contaminants

Contaminant Name Environmental Source

2,4-dinitrotoluene (2,4-

DNT) Used in the production of isocyanate, dyes, and explosives 

2,6-dinitrotoluene (2,6-

DNT) Used as mixture with 2,4-DNT (similar uses)

Acetochlor Herbicide used with cabbage, citrus, coffee, and corn crops

DCPA di-acid degradate Degradation product of DCPA; an herbicide used ongrasses and weeds with fruit

and vegetable crops

DCPA mono-acid degradate Degradationproduct of DCPA; an herbicide used on grasses and weeds withfruit

and vegetable crops

4,4'-dichloro dichlorophenyl

ethylene (4,4'-DDE) Degradation product of DDT; a general insecticide

EPTC Herbicide used on grasses and weeds, with potatoes and corn

Molinate Selective herbicide used with rice; controls watergrass

Methyl-tert-butyl-ether

(MTBE) Octane booster in unleaded gasoline

Nitrobenzene Used in the production of aniline, which is used to make dyes, herbicides, and

drugs

Perchlorate Oxygen additive in solid fuel propellant for rockets, missiles and fireworks

Terbacil Herbicide used with sugarcane, alfalfa, and fruit crops

Note: UCMR (1999) List 1 contaminants are required to be monitored under the Assessment Monitoring

component ofthe revisedUCMR. For more information on Assessment Monitoring, please refer to the final

UCMRPreamble andRule (64 FR 50556), and the Perchlorate and Acetochlor Rule (65 FR11372). Please

refer to Appendix A for a list of acronyms and Appendix B for definitions.

The second component ofthe UCMRincludes ScreeningSurveymonitoring forthe List2 contaminants

for which analytical methods have been developed, but may need to be further refined before largescale Assessment Monitoring is conducted. Each Screening Survey will be conducted at 300 PWSs

(120 large PWSs and 120 small PWSs) randomly selected from the pool of systems required to

conduct Assessment Monitoring. Table 2 lists the contaminants to be monitored and their

environmental sources.
UCMR Reference Guide October 2001

4

Table 2. UCMR (1999) List 2 Contaminants

Contaminant Name Environmental Source

1,2-diphenylhydrazine Used in the production of benzidine and anti-inflammatory drugs

2-methylphenol Released in automobile and diesel exhaust, coal tar and petroleum refining, and

wood pulping

2,4-dichlorophenol Chemical intermediate in herbicide production

2,4-dinitrophenol Released from mines, metal, and petroleum plants 

2,4,6-trichlorophenol By-product of fossil fuel burning, used as bactericide and wood/glue

preservative

Alachlor ESA Degradation product of alachlor and other acetanilide pesticides, herbicides

used with corn, bean, peanut, and soybean crops to control grasses and weeds

Diazinon Insecticide used with rice, fruit, vineyards, and corn crops

Disulfoton Insecticide used with cereal, cotton, tobacco, and potato crops

Diuron Herbicide used on grasses in orchards and with wheat crops

Fonofos Soil insecticide used on worms and centipedes

Linuron Herbicide used with corn, soybean, cotton, and wheat crops

Nitrobenzene (low levels) Used in the production of aniline, which is used to make dyes, herbicides, and

drugs

Prometon Herbicide used on annual and perennial weeds and grasses

RDX Used in explosives; ammunition plants

Terbufos Insecticide used with corn, sugar beet, and grain sorghum crops 

Microbiological Contaminant

Aeromonas Present in all freshwater and brackish water

Note: UCMR(1999) List 2 contaminants are required to be monitored under the Screening Surveycomponent of

the revisedUCMR. For more information on Screening Surveys, please refer to the final UCMR List 2 Rule

(66 FR 2273). Refer to Appendix A for a list of acronyms and Appendix B for definitions.

The third component ofthe UCMRis Pre-Screen Testing, which will be conducted at up to 200 large

and small PWSs. States will be asked to nominate systems that are particularly vulnerable to the PreScreen Testing contaminants. Pre-Screen Testing may be conducted for some of the UCMR (1999)

List 3 contaminants for which analyticalmethods are inthe initialstages ofdevelopment. Table 3 lists

the contaminants that may be monitored and their environmental sources.
UCMR Reference Guide October 2001

5

Table 3. UCMR (1999) List 3 Contaminants

Contaminant Name Environmental Source

Adenoviruses Fecal or hand to mouth transmission

Cyanobacteria (blue-green

algae, other freshwater algae,

and their toxins) 

Bloom in surface water bodies; produce toxins

Caliciviruses Contaminated food and water; raw shellfish

Coxsackieviruses Fecal or hand to mouth transmission

Echoviruses Fecal or hand to mouth transmission

Helicobacter pylori Fecal or hand to mouth transmission

Microsporidia Occur in rivers, ponds, lakes, and unfiltered water

Lead-210 A lead isotope and radionuclide; part of the uranium decay series; naturally

occurring 

Polonium-210 A polonium isotope and radionuclide; part of the uranium decay series;

naturally occurring 

Note: UCMR (1999) List 3 contaminants are required to be monitored under the Pre-Screen Testing component

of the revised UCMR. EPA is conducting analytical methods development for UCMR (1999) List 3

contaminants. For more information on Pre-Screen Testing, refer to the final UCMRPreamble andRule (64

FR 50555). Refer to Appendix A for a list of acronyms and Appendix B for definitions.

EPA also selected 30 small PWSs (PWSs serving 10,000 or fewer persons) to serve as Index

Systems. Index Systems will conduct Assessment Monitoring each year of the 5-year UCMR cycle

to provide additional programmatic and data quality control. The monitoring data that EPA (or its

contractors) will collect for Index Systems will provide information on temporal variations in

contaminant occurrence. Information on the environmental and operating conditions of these 30

systems will also be collected. The detailed information from the Index Systems, together with the

monitoring data generated through the three UCMR monitoring components, will enable EPA to

develop future regulationsthatbetterreflectthe environmental characteristics and operating conditions

of the approximately 65,000 small PWSs.

Generalmonitoring schedules are related to the type ofmonitoring (AssessmentMonitoring, Screening

Survey, or Pre-Screen Testing) being conducted. Each participating system must conduct Assessment

Monitoring of UCMR(1999) List 1 contaminants for a 12-month period in the first three years (2001

through 2003) of the 5-year UCMR contaminant listing cycle (2001-2005), as per

§141.40(a)(5)(ii)(B). Randomly selected large systems will sample for the UCMR (1999) List 2

contaminants in 2002 (for chemical contaminants) and 2003 (for the microbiological contaminant,

Aeromonas), while small systems will sample in 2001 and 2003, respectively. No time-frame has

been established yet for Pre-Screen Testing of the UCMR (1999) List 3 contaminants, but it would

likely be conducted in 2004 or in the next UCMR5-year listing cycle. Within this general timeframe,
UCMR Reference Guide October 2001

6

UCMR monitoring schedules may be varied by the States or EPA to allow coordination of UCMR

monitoring with compliance monitoring whenever possible.

Figures 1 and 2 provide a summary of the UCMR three-tiered monitoring approach, illustrate the

interrelation of the UCMR program components, and show the implementation timeline of UCMR

activities. For identification ofterms used throughout this guidance document, please see Appendix

A for a list of acronyms and Appendix B for a list of definitions.

EPA will directly implement the UCMR, with State participation through Partnership Agreements

(PAs) with EPA. The Agency will pay for the testing and shipping costs of Assessment Monitoring

for the representative sample of the 800 randomly selected small PWSs. EPA will also pay for the

testing and shipping costs of samples for the small PWSs participating in the Screening Surveys and

Pre-Screen Testing components of the UCMR program. However, EPA will not pay for any

monitoring activities for large systems participating in the UCMR. 
UCMR Reference Guide October 2001

7

Assessment Monitoring

List 1 (1999)

Contaminants

Quarterly for surface

water systems, and

2 times, 5 to 7 months

apart for ground water

systems for 1 year, during

2001-2003

7 or more Governors may petition EPA to add

contaminants to list

State

PWS Reporting

Electronically

16 Data

Elements State Monitoring

Plan for

Representative

Sample

EPA UCMR

List

up to 30

contaminants

EPA Pays

for small systems

in Plan, including

Pre-Screen Testing

Public

Notification,

Consumer

Confidence

Report

EPA

National

Drinking

Water

Contaminant

Occurrence

Database

Two Screening

Survey(s) for

List 2 (1999)

Contaminants

300 randomly selected

systems in each

Screening Survey

State may apply to

EPA for

contaminant

monitoring waiver

State-EPA

Partnership

Agreement for

Implementation

All large systems

Representative

Sample of 800

small systems

randomly selected

by EPA

Figure 1: Unregulated Contaminant Monitoring Approach
UCMR Reference Guide October 2001

8

UCMR Issued,

Guidance

Available

Next Candidate

Contaminant

List Issued

Next UCMR

List Issued

Analyze Results

National 

Drinking Water 

Contaminant

Occurrence

Database

Operational

 1999 2000 2001 2002 2003 2004 2005

UCMR (1999): IMPLEMENTATION TIMELINE

Programmatic Activities

Monitoring Activities

Screening Surveys

List 2 (1999) Contaminants

Assessment Monitoring 

List 1 (1999) Contaminants 

All large and 800 small PWSs

Index System Monitoring

30 small PWSs

Screening

Survey

Chemical

(180 small

PWSs only)

Screening

Survey

Chemical

(120 large

PWSs only)

Screening

Survey

Micro

(300 large

and small

PWSs)

EPA Contract

Laboratories

Operational

(for small

systems)

State PAs and

State Plans

Developed:

Inform PWSs

Representative

Sample Selected

UCMR (1999)

List 2 Rule

Promulgated

Perchlorate,

Acetochlor

Methods

Approved

Assess Data Quality

Figure 2: UCMR (1999) Implementation Timeline and Related Activities
UCMR Reference Guide October 2001

9

This document provides a general overview of the UCMR program, including a description of how

PWSs, States, and the EPA are affected by this regulation, and the responsibilities each party has in

implementing the UCMR. This document contains a list of all contaminants to be monitored under the

UCMR and describes the contaminant monitoring, analysis, and reporting process. It includes the

following sections: Affected Entities and Their Responsibilities (Section 2), Contaminants to be

Monitored (Section 3), Sample Collection and Analysis (Section 4), General Monitoring

Requirements(Section5), UCMRReporting Requirements (Section 6), State Responsibility (Section

7), Tribal Responsibility (Section 8), EPA Responsibility (Section 9), and Contact Information

(Section10). Further information about the UCMR program can be found in the UCMR Preamble and

final Rule (64 FR 50556), the Perchlorate and Acetochlor Rule (65 FR 11372), the List 2 Rule (66

FR 2273), and UCMR guidance documents. 

The documents listed below present detailed informationonUCMRprogramrequirements for PWSs,

States, and EPA Regions who are responsible for UCMR program planning, implementation, and

oversight. 

Please note: Because of the evolving nature of the UCMR program, supplemental rule-making

efforts may add additional contaminants to be monitored and hence, additional sampling and

analytical procedures may need to be identified. For this reason, EPA will issue supplemental

guidance explaining any new requirements. EPA anticipates developing supplemental guidance

after analytical methods are approved for monitoring the UCMR (1999) List 2 and 3 contaminants

in subsequent rules.

Background Documents

1. Technical Background Information for the Unregulated Contaminant Monitoring Regulation

EPA 815-R-99-007

This document summarizes the process used to select contaminants for the UCMR List

(1999) and a brief summary of the CCL selection process. This document also provides an

overview of the proposed methods for monitoring UCMR contaminants.

2. Statistical Design and Sample Selection for the Unregulated Contaminant Monitoring

Regulation (1999)

EPA 815-R-01-004

This document replaces National Representative Sample of Small Public Water Systems:

Statistical Design and State Plans for Unregulated Contaminant Monitoring, EPA815-R99-003. It describes the way in which the sample of small PWSs was selected for

participation in the UCMR Assessment Monitoring. This document also describes the

selection process for Screening Survey, the probable selection process for the Pre-Screen

Testing systems, and briefly describes how Index Systems were selected. 

Guidance Documents

1. UCMR (1999) List 1 and List 2 Chemical Analytical Methods Quality Control Manual

EPA 815-R-01-028

This document replaces the UCMR Analytical Methods and Quality Control Manual and

Supplements, and adds the new analytical methods quality control (QC) information from

UCMR (1999) List 2.
UCMR Reference Guide October 2001

10

2. Unregulated Contaminant Monitoring Regulation Guidance for Operators of Public Water

Systems Serving 10,000 or Fewer People

EPA 815-R-01-002

This document identifies the sampling and reporting responsibilities ofsmall PWSsselected

to participate in the Assessment Monitoring component of the UCMR. This guidance also

highlights important changes in the UCMRwhich reduce the monetary and administrative

burden on small systems. 

Please Note: A draft of this document was released for public comment as EPA 815-R-99-

005, and a subsequent final document was release with the number EPA 815-R-00-018.

This final guidance document is being released with the number EPA 815-R-01-002, and

replaces the previous versions.

3. Unregulated Contaminant Monitoring Regulation Reporting Guidance

EPA 815-R-01-029

This document will provide general guidance to PWSs, States, and EPA Regions on

reporting requirements for the results of contaminant monitoring, and inventory

information for the UCMR.

4. Implementation Guide for Unregulated Contaminant Monitoring Rule:

Volume I – Introduction to CDX and UCMR Submission

Volume II – Web Forms

Volume III – [not relevant to UCMR]

Volume IV – XML Standards for Submitting Data

Volume V – Flat File Format

Forthcoming

This five volume document provides detailed information on how to use the EPA Central

Data Exchange and the Safe Drinking Water Accession and Review System for the UCMR.

This guidance is available on the Web at: http://epacdx.lmi.org/FAQ.asp.

Fact Sheets

1. UnregulatedContaminantMonitoring Regulation: Monitoring for List 1 Contaminants by Large

Public Water Systems

EPA 815-F-01-003

This is a fact sheet for large public water systems which provides a brief overview of their

responsibilities in implementing the Assessment Monitoring portion of the UCMR.

2. Unregulated Contaminant Monitoring Regulation: Monitoring for List 1 Contaminants by

Small Public Water Systems

EPA 815-F-01-004

This is a fact sheet for small public water systems which provides a brief overview of their

responsibilities in implementing the Assessment Monitoring portion of the UCMR.

3. Unregulated Contaminant Monitoring Regulation: Screening Survey for List 2 Contaminants

by Selected Large Public Water Systems

EPA 815-F-01-005

This is a fact sheet for large public water systems which provides a brief overview of their

responsibilities in implementing the Screening Survey portion of the UCMR.
UCMR Reference Guide October 2001

11

4. Unregulated Contaminant Monitoring Regulation: Screening Survey for List 2 Contaminants

by Selected Small Public Water Systems

EPA 815-F-01-006

This is a fact sheet for small public water systems which provides a brief overview of their

responsibilities in implementing the Screening Survey portion of the UCMR.

5. Unregulated Contaminant Monitoring Regulation: Monitoring by Index Systems

EPA 815-F-01-007

This is a fact sheet for Index Systems which provides a brief overview of their

responsibilities in implementing the UCMR. 

The documents listed above with document numbers are available through the EPA Safe Drinking

Water Hotline at (800) 426-4791, or at EPA’s UCMR Website:

http://www.epa.gov/safewater/ucmr.html. Note that the guidance documents above generally outline

the sampling and reporting responsibilities for the Assessment Monitoring, and Screening Survey

components of the UCMR (1999). EPA will issue further guidance on Pre-Screen Testing

requirements and responsibilities after the List 3 rule is promulgated.
UCMR Reference Guide October 2001

12
UCMR Reference Guide October 2001

13

2. Affected Entities and Their Responsibilities

2.1 Large Public Water Systems

2.1.1 Assessment Monitoring

All large CWSs and NTNCWSs are required to conduct UCMR Assessment Monitoring including

contaminant sampling, analysis, and reporting (§141.40(a)(ii)). Large systems are those serving

greater than 10,000 persons. CWSs are PWSs which serve at least 15 service connections used by

year-round residents orregularly serve at least 25 year round residents. NTNCWSs are PWSs which

are not CWSs, and that regularly serve at least 25 of the same persons over six months per year.

Transient non-community water systems (TNCWSs), systems that do not regularly serve at least 25

of the same persons over six months per year, are not required to monitor under the UCMR. Large

systems that purchase all of their water from other PWSs are also not required to monitor for the

AssessmentMonitoring or Screening Survey portion ofthe UCMR(§141.40(a)(iii)). However, some

PWSs that purchase water from a PWS selected to monitor for Aeromonas may be asked to collect

a distributionsystemsample. All of the 2,800 large PWSs will be included in the UCMR Assessment

Monitoring. 

Sample collection responsibilities are discussed in Section 4, general monitoring requirements are

discussed in Section 5, and reviewing and reporting responsibilities are discussed in Section 6.

2.1.2 Screening Surveys

The Screening Survey component for large PWSs (§141.40(a)(ii) and §141.40(a)(iii)) is currently

divided into two phases, a Screening Survey for chemical contaminants and a Screening Survey for

microbiological contaminants. One hundred and twenty (120) randomly selected large PWSs will be

required to conduct monitoring for the Screening Survey List 2 chemical contaminants during 2002.

A different group of120 large PWSs will be required to conductmonitoring for the Screening Survey

List 2 microbiological contaminant Aeromonas during 2003. Each Screening Survey was targeted to

consistof60 systems serving more than 50,000 persons and 60 systems serving from10,001 to 50,000

persons. The large Screening Survey Systems are furthersubdivided by water source type (targeted

to be 30 ground water and 30 surface water systems). Since there were too few small surface water

systems, and too few large ground water systems, the number of systems had to be re-allocated to

small ground water and large surface water systems. These Screening Survey systems were selected

fromthe pool of systems conducting Assessment Monitoring. Note that some PWSs which purchase

water from a systemselected to monitor for Aeromonas may be asked to collect distribution system

samples. EPA has already identified the randomly selected large systems that will monitor for List

2 contaminants, and has placed this list on its Web site at

http://www.epa.gov/safewater/standard/ucmr/systems.html. 

Depending on the terms of PAs developed by EPA and the States, either EPA or the State may have

notified large PWSs of their requirements to monitor for Screening Surveys (see section 7 for more

information on the development of PAs). Selected large PWSs are responsible for Screening Survey

sampling in 2002 for UCMR (1999) List 2 chemical contaminants, or for Screening Survey sampling

forAeromonasin2003. Large systems may coordinate Assessment Monitoring with Screening Survey

monitoring by collecting samples atthe same time. Note, however, that all Screening Survey samples

for List 2 chemical contaminants must be collected from the entry points to the distribution system
UCMR Reference Guide October 2001

14

(EPTDS), and notraw water sources (§141.40(a)(7)). This ensures that Screening Survey analytical

results may be used to provide an accurate estimation of frequency of contaminant occurrence in

finished drinking water sources nationwide. 

2.1.3 Pre-Screen Testing

For the Pre-Screen Testing component, up to 200 systems (including both large and small systems)

maybe selected to conductUCMRList3monitoring (§§141.40(a)(ii) and 141.40(a)(iii)). Pre-Screen

Testingmay be conducted for contaminants on the UCMR(1999) List 3 whose analyticalmethods are

in the early stages of development. The Pre-Screen Testing systems will be selected by EPA or

States, based on the system’s vulnerability to the UCMR(1999) List 3 contaminants. The goal of this

monitoring is to determine whether the List 3 contaminants can be found in any public water system

under contaminant-specific, most-likely-occurrence conditions. Thus, this tier of UCMR monitoring

is notdesigned to determine the extent ofoccurrence, butratherto testfor appropriateness and validity

of analytical methods that might be used in a broader monitoring effort (i.e., a future round of

Assessment Monitoring). Note that the systems which would be selected to monitor for Pre-Screen

Testing contaminants may or may not be the same systems conducting Assessment Monitoring or

Screening Survey Monitoring. Pre-Screen Testing will begin after EPA promulgates the List 3 rule.

More complete details on the definition of vulnerability and the vulnerable systemselection process

will be provided in future guidance from EPA.

EPA or the State will notify the large systems which have been selected to monitor for UCMR(1999)

List 3 contaminants. Large systems will be responsible for collecting their own samples, sending the

samples to an EPA-specified laboratory, and reporting the results to EPA with a copy to the State

(§141.40(a)(7)(i) and (ii)). EPA will provide further guidance on Pre-Screen Testing, and large PWS

responsibility before Pre-Screen Testing requirements begin (§141.40(a)(7)(i)).

2.2 Small Public Water Systems

2.2.1 Assessment Monitoring

Section 1445(a)(2) of SDWA mandatesthat only a representative sample ofsmall PWSs be required

to monitor for unregulated contaminants. A group of 800 small CWSs and NTNCWSs was selected

from the total number of approximately 66,000 small systems nationwide to monitor for the UCMR.

The process used to select thissubset ofsmall systems was designed to provide a statistically valid,

nationally representative sample ofthe nation’s small PWSs serving 10,000 or fewer people. Only

the small CWSs and NTNCWSsthat are notified by their State or EPA will be required to participate

in UCMR sampling. TNCWSs are not required to monitor under the UCMR.

Through its specified contractor, EPA will provide all 800 participating small systems with

instructions to collect samples. The overall programis designed to minimize the burden to the small

systems selected to monitor. Most significantly, EPA will pay for the cost of shipping and analyzing

these samples. 

To ensure that the 800 small systems included in the national representative sample adequately

represent the total population ofsmall PWSs, the sample was stratified based on population served,

source water type (ground water or surface water), and geographic location (i.e., State). Small

systems were then randomly selected within these stratifications to ensure that at least two systems

were selected in each State (except in Guam, where there was only one active small system eligible
UCMR Reference Guide October 2001

15

for UCMR monitoring). For more information on the statistical design of the national representative

sample, please refer to the document entitled Statistical Design and Sample Selection for the

Unregulated Contaminant Monitoring Regulation (1999), EPA 815-R-01-004. Table 4 shows the

number of small systems that were selected to monitor for UCMR (1999) List 1 contaminants by

systemsize and source of water. Appendix C shows the number of small systems selected to monitor

for List 1 contaminants in each State.

Table 4. Total Number of Small Systems in National Representative Sample to Conduct

Assessment Monitoring (by Size, Type, and Water Source)

Population

CWS NTNCWS

Total Ground

Water

Surface

Water CWS Total GroundWater

Surface

Water

NTNCWS

Total

25-500 76 45 121 36 8 44 165

501-3300 214 39 253 30 7 37 290

3,301-10,000 231 105 336 4 5 9 345

Total 521 189 710 70 20 90 800

Smallsystems are responsible for properlystoring, maintaining, and using the sampling equipment sent

out by the EPA contractor, collecting water samples, and sending the samples to the EPA-specified

laboratory to be analyzed (§141.40(a)(4)(i)(A), (5)(iii)(B) and (5)(iii)(H)). In some cases, States

may elect to conduct the sampling, especially in those that currently collect water samples for

regulated contaminant compliancemonitoring. States may inform small PWSs of their responsibilities,

depending on the terms of individual State PAs (see Section 7).

2.2.2 Screening Surveys

One hundred and eightysmallsystems will be required to conductmonitoring forthe ScreeningSurvey

for List 2 chemical contaminants in 2001. A different group of small systems will be required to

conduct monitoring for the Screening Survey for Aeromonas in 2003. The small Screening Survey

systems were randomly selected from the pool of small systems scheduled to conduct Assessment

Monitoring in that same year. Thus, if a system was selected to monitor for UCMR (1999) List 1

contaminants in 2001, that system was only eligible to be selected for the Screening Survey in 2001.

Monitoring years were selected in this manner so that Assessment Monitoring and the Screening

Survey for List 2 chemical contaminants could be coordinated for eachsmallsystem. Each Screening

Survey was targeted to consist of 60 systems from each of the following service size categories: 25

to 500 persons, 501 to 3,300 persons, and 3,301 to 10,000 persons. The number of systems selected

in each size category was further stratified by source water type (ground water or surface water).

EPA has already identified the Screening Survey Systems for each State. These systems are found in

each UCMR State Monitoring Plan for small systems. 
UCMR Reference Guide October 2001

16

Small PWSs selected to monitor for the Screening Surveys may be notified by their State or EPA,

depending upon the terms of individual State PAs. Sampling for the Screening Survey for List 2

chemical contaminants in 2001 will be collected at the same frequencyasfor Assessment Monitoring

to minimize the burden of sample collection (§141.40(a)(7)). Systems selected to participate in the

Screening Survey for Aeromonas will collectsamples fromthree sites withinthe distribution system.

The Screening Survey for Aeromonas will not be able to be conducted entirely at the same time as

Assessment Monitoring in 2003, since the samples must be collected from different locations and at

different frequencies. 

The EPA-specified contractor will review the sampling results, and the EPA-specified laboratories

will report the analytical results forsmall PWSs. Small systems are still responsible for ensuring that

a copy ofthe results are reported to the State, and for ensuring compliance with any other applicable

State reporting requirements. 

2.2.3 Pre-Screen Testing

Up to 200 large and small PWSs will be selected for Pre-Screen Testing. Systems that are most

vulnerable to the particular UCMR(1999) List 3 contaminants will be identified by States or EPAfor

Pre-Screen Testing. List 3 contaminants are those whose analytical methods are in the early stages

of development. States or EPA may select systems outside of the 800 selected for Assessment

Monitoring for this targeted testing. More complete details on the definition of vulnerability and the

vulnerable system selection process will be provided in future guidance from EPA, once the List 3

rule is promulgated.

EPA or the State may notify the small systems which have been selected to monitor for these

contaminants, depending on the terms of individual State PAs. For small systems, EPA pays for the

cost of sample shipping, analysis, and reporting. EPA will report the results of Pre-Screen Testing

for the small systems. EPA will provide further guidance on Pre-Screen Testing, and small PWS

responsibility before small systems will be required to monitor for Pre-Screen Testing contaminants

(§141.40(a)(7)(ii)). 

2.3 Index Systems

To provide a more thoroughunderstanding ofcontaminants and conditions affecting smallsystems, and

to provide additional data quality assurance for the UCMR data analysis, EPA has selected 30 small

PWSs as “IndexSystems” fromthe 800 systems that conductAssessment Monitoring. Index Systems

will conduct Assessment Monitoring every year during the 5-year UCMRcycle, and are required to

provide EPA with additional environmental and system operation information. To minimize the

additional burden on these systems, EPA will provide for field technicians to assist with sample

collection, and will pay for the cost of shipping and testing UCMR samples. In some cases, States

may collect the samples for the small systems, rather than the EPA-specified contractor. 

Owners/operators of Index Systems are required to assist EPA in identifying appropriate sampling

locations and provide information on wells and intakesinuse atthe time ofsampling, well casing and

screen depth (if known) for those wells, and the pumping rates of each well or intake at the time of

sampling. EPA will collect detailed observations of system operation that may affect contaminant

occurrence, such as nature of the source water (type of aquifer or surface water body), number of

wells, well depth, configuration of source water intake, treatment, entry points, and how sources are

used (seasonally, blended, etc.), as well as other environmental factors. At the time of sampling, EPA,

or its contractors, will also gather additional system information to characterize the environmental
UCMR Reference Guide October 2001

17

setting affecting the system including precipitation, land and water resource use, and environmental

factors (such as soil type and geology). This information will assist EPA in more fully evaluating

small system operations, and in developing or modifying future regulations for small systems. 

2.4 State and Tribal Participation

To minimize the burden of monitoring and data collection efforts on States, Tribes, and Territories,

EPA will directly implement the UCMR. However, EPA has encouraged Statesto become involved

in the UCMR program through PAs with EPA. The PAs facilitate State participation in the

development and implementation of State Monitoring Plans (SMPs). The States, through the

provisions of the SMPs, reviewed and modified the list of systems required to sample, and in some

cases, sampling locations. See Section 7 for a more complete description of State participation and

Section 8 for Tribal participation. Some States decided not to participate in PAs, in which case EPA

established the State Monitoring Plan (SMP) by review of State inventory or direct contact with

systems. 
UCMR Reference Guide October 2001

18
UCMR Reference Guide October 2001

19

3. Contaminants to be Monitored

3.1 Assessment Monitoring

There are 12 unregulated chemical contaminants onthe UCMR(1999) List 1. Analytical methods are

currently available for all of these contaminants and most of these methods are approved for

compliance monitoring (exceptions include EPA Methods 314.0 and 515.4). The List 1 contaminants

and their common environmental sources are listed in Table 1. Assessment Monitoring is discussed

ingreater detail throughoutthis document as itrelatesto monitoring requirements, and PWS,State, and

EPA responsibility.

3.2 Screening Surveys

There are 15 unregulated chemical contaminants onthe UCMR(1999) List 2, and one microbiological

contaminant (Aeromonas). The List 2 contaminants are shown in Table 2. EPA is conducting the

Screening Surveys to analyze for contaminants where the use of newly developed, non-routine

analytical methods are required. The Screening Surveys will help EPA to identify whether a

contaminant of concern is occurring in drinking water and to estimate the range of concentrations of

thatoccurrence. The Screening Surveys are also intended to allow EPA to screen contaminants to see

iftheyoccur athighenough frequencies or at concentrations thatjustify inclusion in future unregulated

contaminantAssessment Monitoring, or atsufficiently low frequencies thattheydo notrequire further

monitoring.

Analytical methods for RDX and alachlor ESA are currently being refined by EPA. Monitoring for

these contaminants is not scheduled for the Screening Surveys. EPA may conduct a third Screening

Survey for these contaminants in the 2001 - 2005 round of UCMR monitoring if analytical methods

can be developed and validated for use. For more information on this rule, please refer to the List 2

Rule (66 FR 2273). 

Note that low level nitrobenzene was added to UCMR (1999) List 2. EPA requires monitoring for

nitrobenzene in Assessment Monitoring between 2001 and 2003, using the methods approved in 64

FR 50556. The approved analytical methods for Assessment Monitoring can accurately measure

levels of nitrobenzene at concentrations above 10 μg/L; however, recent health effects information

indicates that nitrobenzene may be a health concern at lower concentrations. Methods reliably

detecting nitrobenzene at concentrationslessthan10 μg/Lwere notavailable atthe time ofpublication

of the September 1999 final UCMR (64 FR 50556). Through additional methods research, EPA

developed and refined EPA Method 526, which enables EPA to measure several contaminants on

UCMR(1999) List 2, including nitrobenzene, below 10 μg/L. The analytical methods used to detect

nitrobenzene under Assessment Monitoring and the Screening Survey can be used to detect several

other contaminants on Lists 1 and 2. Because of this, analysis of nitrobenzene will not impose

additional costs on systems. Screening Survey monitoring is discussed in greater detail throughout

this document as it relates to monitoring requirements, and PWS, State, and EPA responsibility.
UCMR Reference Guide October 2001

20

3.3 Pre-Screen Testing

There are nine contaminants on the UCMR (1999) List 3, including seven microbiological

contaminants and tworadiological contaminants. These contaminants and their common environmental

sources are listed in Table 3. EPA may conduct Pre-Screen Testing to determine the validity of

analytical methods that might be used in a broader monitoring effort (i.e., in a future round of

Assessment Monitoring). Pre-Screen Testing is discussed in greater detail throughout this document

as it relates to monitoring requirements, and PWS, State, and EPA responsibility.

3.4 Water Quality Parameters

Both large and small PWSs must analyze water quality parameters (WQPs) whenmonitoring UCMR

microbiological contaminants. This currently includes the List 2 Screening Survey contaminant

Aeromonas. In the future, this is also likely to include many of the List 3 Pre-Screen Testing

contaminants. WQPs must be monitored for each sampling event at each sampling point, using the

method(s) indicated in Table 5. 

Table 5. Water Quality Parameters to be Monitored with UCMR Microbiological

Contaminants

Parameter Contaminant

Type

Methodology

EPA

Method

Standard

Methods1 Other

pH Microbiological 150.12 

150.22 4500-H+ B ASTM D1293-843ASTM D1293-953

Turbidity Microbiological 180.14,5 2130 B4 GLI Method 24,6

Temperature Microbiological 2550

Free

Disinfectant

Residual 

Microbiological

4500-Cl D

4500-Cl F

4500-Cl G

4500-Cl H

4500-ClO2 D

4500-ClO2 E

4500-O3 B

ASTM D 1253-863

Total

Disinfectant

Residual 

Microbiological

4500-Cl D

4500-Cl E4

4500-Cl F

4500-Cl G4

4500-Cl I

ASTM D 1253-863

The analytical proceduresshall be conducted in accordance with the documents listed in these footnotes. Copies of

the documents may be obtained from the sources listed in these footnotes. Information regarding obtaining these

documents can be obtained fromthe Safe Drinking Water Hotline at 800-426-4791. Documents may be inspected at

EPA’s Drinking Water Docket, 401 M Street, SW., Washington, DC 20460 (Telephone: 202-260-3027); or at the

Office of Federal Register, 800 North Capitol Street, NW., Suite 700, Washington, DC.

1

 The 18thand 19th Editions of Standard Methods for the Examination of Water and Wastewater, 1992 and 1995.

Methods 2130 B; 2550; 4500-Cl D, E, F, G, H, I; 4500- ClO2 D, E; 4500-H+ B; and 4500-O3 B in the 20th edition

Standard Methods for the Examination of Water and Wastewater, 1998, American Public Health Association, 1015

Fifteenth St. NW, Washington D.C., 20005. 
UCMR Reference Guide October 2001

21

2

 Methods 150.1 and 150.2 are available from US EPA, NERL, 26 W. MartinLuther King Dr.,Cincinnati,Ohio45268.

The identical methods are also in “Methods for Chemical Analysis of Water andWastes,” EPA-600/4-79-020,March

1983, available fromthe National Technical InformationService (NTIS), U.S. Department of Commerce, 5285 Port

Royal Rd., Springfield, Virginia 22161, PB84-128677. (Note: NTIS toll-free number is 800-553-6847.)

3

 Annual Book of ASTM Standards, Editions 1994, 1996, 1998 and 1999, Volumes 11.01, American Society for

Testing and Materials, 100 Barr Harbor Drive, West Conshohocken, PA 19428. Version D1293-84 is located in the

Annual Book of ASTM Standards, 1994, Volumes 11.01. VersionD1293-95 is located in the Annual Book of ASTM

Standards, 1996, 1998 and 1999, Volumes 11.01.

4

 “Technical Notes on Drinking Water,” EPA-600/R-94-173, October 1994, Available at NTIS, PB95-104766.

5

 “Methods for the Determination of Inorganic Substances in Environmental Samples,” EPA-600/R-93-100, August

1993. Available at NTIS, PB94-121811

6

 GLI Method 2, “Turbidity,” November 2, 1992, Great Lakes Instruments Inc., 8855 North 55th St., Milwaukee,

Wisconsin 53223.
UCMR Reference Guide October 2001

22
UCMR Reference Guide October 2001

23

4. Sample Collection and Analysis for UCMR (1999) Contaminants

4.1 Large Public Water Systems

Large PWSs are responsible for collecting all UCMR samples in accordance with the timing and

frequency requirements presented in Section 5. Large systems must follow the sampling quality

control procedures required under §141.40(a)(1)(ii) and (iv) and described inthe UCMR(1999) List

1 and List 2 Chemical Analytical Methods QC Manual (EPA 815-R-01-028). Once samples are

collected, large PWSs are responsible for sending the samples to an EPA-approved laboratory for

analysis (§141.40(a)(4)(ii), (5)(ii)(G), and (7)(i)). Laboratory certification requirements are

discussed in 40 CFR §141.28, as well as the QC Manual. Systems that have laboratories approved

to perform UCMR analysis on-site may analyze their own Assessment Monitoring and Screening

Survey samples, but the laboratories must follow the required methods and quality control

requirements outlined in the QC Manual (§141.40(a)(4)(ii), (5)(ii), and (7)(ii)). If samples are sent

out to a laboratory, it is the responsibility of the owner/operator to use laboratories that are certified

under §141.28, and approved to conduct UCMR analyses, and that these laboratories conformto the

methods and quality control requirements approved in the UCMR. Note that for perchlorate and

Aeromonas there are special Performance Evaluation program requirements. 

4.2 Small Public Water Systems

Small PWSs are responsible for collecting all UCMR samples in accordance with the timing and

frequency requirements in Section 5. However, some States will collect samples for the small

systems. Those sampling for small systems must follow the sampling quality control procedures as

directed in the instructions included in sample collection kits (§141.40(a)(4)(iii), (5)(iii), and

(7)(iii)). Once the samples are collected, small PWSs are responsible for sending the samples to the

EPA-specified laboratory for analysis (§141.40(a)(4)(iii), (5)(iii)(H), and (7)(ii)). 
UCMR Reference Guide October 2001

24
UCMR Reference Guide October 2001

25

5. General Monitoring Requirements

5.1 Monitoring Frequency and Sampling Location

For chemical contaminants, systems will sample fromall EPTDS or othersampling points specified

by the State that represent all principal sources of water used over the monitoring period. Note that

systems may sample raw water sources for UCMR (1999) List 1 contaminants, if this is the

compliance monitoring point required by the State. If a UCMR contaminant is detected, the system

must also then initiate monitoring at the EPTDSsforthose contaminants detected. Once systems begin

monitoring at EPTDSs, they must continue to monitor at these entry points for the next 12-month

period, even if the monitoring extends beyond the end of 2003. This flexibility in the sampling

location should enable systems and States to coordinate compliance and unregulated contaminant

monitoring more extensively. However, all UCMR (1999) List 2 chemical contaminants must be

collected at entry points to the distribution system to ensure consistent sampling results nationwide

(§141.40(a)(7)). 

For UCMRchemical monitoring, surface water-supplied systems will monitor at each ofthese points

every three months for a 12-month period and ground water-supplied systems will monitor at each of

these points two times, five to seven months apart, within a 12-month period. Table 6 lists the

monitoring frequencies based on contaminant type and source of water. 

One ofthe monitoring events for both surface water and ground watersystems must occur at the most

vulnerable time of year for the PWS. The default vulnerable time is defined as May 1 through July

31, unless otherwise specified by EPA or the State. Sampling during the most vulnerable time will

provide data representing potential variation in contaminant concentration over the course of a year.

It is essential that such variations are captured during data collection to evaluate human exposure

related to contaminant occurrence. Some systems perform their regulated chemical monitoring on a

quarterly basis and cancollectUCMRsamples coincidentwith their compliance samples to minimize

the labor burden associated with UCMR monitoring. Other systems may only conduct compliance

monitoring once every third year and will therefore have to collect additional samples under the

UCMR. These systems can collect one UCMR sample coincident with this compliance sample.

However, EPA requires that ground water systems take a second sample five to sevenmonths earlier

or later to provide data on seasonal variation. 

Systems selected to monitor for Aeromonas as part of List 2 (Screening Survey) monitoring will

collect samples once each quarter, with additional samples taken each month during the warmest

quarter ofthe year, July through September (i.e., six times during the year). This means thatsampling

must take place in each of the six (6) months of either: January, April, July, August, September,

October; or February, May, July, August, September, November; or March, June, July, August,

September, December; unless the State or EPA informs the system otherwise. Collecting these six

samples will increase the likelihood of detecting sporadic microbial occurrence. Three samples will

be collected fromeachsystemfor eachsampling event. Sampling locations must include one midpoint

in the distributionsystemwhere the disinfectant residual will be expected to be typical for the system

(midpoint, or MD, as defined intheRule), and two other points: one of maximumretention time (point

of maximum residence, or MR, as defined in the Rule), and one where the disinfectant residual will

have typically declined (location of lowest disinfectant residual or LD, as defined in the Rule).
UCMR Reference Guide October 2001

26

Table 6. Monitoring Frequency by Contaminant and Water Source Types

Contaminant Type Water Source Type Timeframe Frequency

Chemical Surface water Twelve (12) months Four (4) quarterly samples taken as

follows: Select either the first,

second, or third month of a quarter and

sample in that same month of each of

four (4) consecutive quartersa to

ensure that one of those sampling

events occurs during the vulnerable

timeb

Ground water Twelve (12) months Two (2) times in a year taken as

follows: Sample during one (1) month

of the vulnerable timeb and during one

(1) month five (5) to seven (7) months

earlier or laterc

Microbiological Surface and ground

water

Twelve (12) months Six (6) times in a year taken as

follows: Select either the first,

second, or third month of a quarter and

sample in that same month of each of

four (4) quarters, and sample an

additional two (2) months during the

warmest (vulnerable) quarter of the

year.

d

a

“Select either the first,second,or thirdmonthof a quarter and sample in that same monthof each of four consecutive

quarters” means that the systemmust monitor during each of the four months of either: January, April, July, October;

or February, May, August, November; or March, June, September, December.

b

 “Vulnerable time” means May 1 through July 31, unless the State or EPA informs the system that it has selected a

different time period for sampling as its vulnerable time.

c

“Sample during one month of the vulnerable time and during one monthfive to sevenmonths earlier or later”means,

for example, that if the system selects May as its “vulnerable time” month to sample, then one month five to seven

months earlier would be either October, November, or December of the preceding year, and one month five to seven

months later would be either, October, November, or December of the same year.

d This means that the system must monitor during each of the six months of either: January, April, July, August,

September, October, or February, May,July, August, September, November, or March,June,July, August,September,

December; unless the State or EPA informs the system that a different vulnerable quarter has been selected for it.

Sites selected for Aeromonas samples may be, and should be, where possible, the same locations

identified for other drinking water contaminants which may occur under similar conditions. For

example,samples for coliformindicator bacteria, as described in 40 CFR §141.21, are taken from a

variety of locations through the distribution system. More specifically, some of these samples are

fromlocations where the disinfectant residual is representative ofthe distribution systemand has not

significantly declined. Locations specified in the sample plan for coliform bacteria that meet this

description could be used for the Aeromonas midpoint sample. Additionally, Aeromonas samples

mustbe taken fromtwo locations in the distributionsystemwhere the disinfectantresidual is expected

to be low. This is similar to total trihalomethane (TTHM) sampling points, as described in 63 FR

69468, the Disinfectants and Disinfection Byproducts Rule, and 40 CFR §141.30. These sample

locations are at distal parts of the distribution system (taking care to avoid disinfectant booster
UCMR Reference Guide October 2001

27

stations) or dead ends, orlocations previously determined to have the lowest disinfectant residualfor

systems which disinfect. 

5.2 General Quality Control Requirements

Sampling and laboratoryquality controlrequirements promote propersample collectionand analyses

to ensure that the EPA obtains the most reliable monitoring data possible. This is particularly

important since UCMR data will only be collected from approximately 3,600 systems (about 2,800

large systems and 800 small systems). To ensure reliable data, EPA is specifying the use of specific

analytical methodsthat are currently available for monitoring (§141.40(a)(3), Table 1). While many

of these methods are routinely used by commercial and PWS laboratories (including some that are

currently used for compliance monitoring), they have not necessarily been used routinely for the

contaminants on the UCMR(1999) List. As shown in Table 7, methods other than those that EPA has

developedmaybe approved for use, butquality control proceduresmustalso be followed asspecified

in §141.40(a)(3),(4) and (5), and §141.40 Appendix A (64 FR 50556). 

Table 7 lists the approved analytical methodsfor UCMR(1999) List 1 contaminants, and Table 8 lists

analytical methods for List 2 contaminants. More detailed information on these analytical methods

can be found in the UCMR (1999) List 1 and List 2 Chemical Analytical Methods QC Manual (EPA

815-R-01-028). Once List 3 methods are fully developed, reviewed, and refined, EPA will provide

further guidance for the List 3 contaminants. 

Table 7. Unregulated Contaminant Monitoring Regulation (1999) List 1

1-Contaminant

2-CAS

registry

number

3-Analytical

methods

4-

Minimum

reporting

level

5-Sampling

location

6-Period during

which monitoring

to be completed

List 1 - Assessment Monitoring Chemical Contaminants

2,4-dinitrotoluene 121-14-2 EPA Method 525.2a2 μg/Le EPTDS f 2001-2003

2,6-dinitrotoluene 606-20-2 EPA Method 525.2a2 μg/Le EPTDS f 2001-2003

Acetochlor 34256-82-

1

EPA Method 525.2a2 μg/Lo EPTDS f 2001-2003

DCPA mono-acid

degradate h

887-54-7 EPA Method 515.1a

EPA Method 515.2a

EPA Method 515.3i,j

EPA Method 515.4k

D5317-93b

AOAC 992.32c

1 μg/Le EPTDS f 2001-2003

DCPA di-acid

degradate h

2136-79-0 EPA Method 515.1a 

EPA Method 515.2a 

EPA Method 515.3i,j

EPA Method 515.4k 

D5317-93b 

AOAC 992.32c

1 μg/Le EPTDS f 2001-2003
UCMR Reference Guide October 2001

Table 7. Unregulated Contaminant Monitoring Regulation (1999) List 1

1-Contaminant

2-CAS

registry

number

3-Analytical

methods

4-

Minimum

reporting

level

5-Sampling

location

6-Period during

which monitoring

to be completed

List 1 - Assessment Monitoring Chemical Contaminants

28

4,4'-DDE 72-55-9 EPA Method 508a 

EPA Method 508.1a

EPA Method 525.2a

D5812-96b

AOAC 990.06c

0.8 μg/Le EPTDS f 2001-2003

EPTC 759-94-4 EPA Method 507a 

EPA Method 525.2a

D5475-93b

AOAC 991.07c

1 μg/Le EPTDS f 2001-2003

Molinate 2212-67-1 EPA Method 507a

EPA Method 525.2a

D5475-93b

AOAC 991.07c

0.9 μg/Le EPTDS f 2001-2003

MTBE 1634-04-4 EPA Method 502.2a,n

SM 6200Cd,n

EPA Method 524.2a

D5790-95b

SM 6210Dd

SM 6200Bd

5 μg/Lg EPTDS f 2001-2003

Nitrobenzene 98-95-3 EPA Method 524.2a

D5790-95b

SM6210Dd

SM6200Bd

10 μg/Lg EPTDS f 2001-2003

Perchlorate 14797-73-

0

EPA Method 314.0l4 μg/L m EPTDS f 2001-2003

Terbacil 5902-51-2 EPA Method 507a 

EPA Method 525.2a

D5475-93b

AOAC 991.07c

2 μg/Le EPTDS f 2001-2003

Column headings are:

1-Chemical or microbiological contaminant: the name of the contaminants to be analyzed.

2-CAS (Chemical Abstract Service Number) Registry Number or Identification Number: a unique number identifying

the chemical contaminants.

3-Analytical Methods: method numbers identifying the methods that must be used to test the contaminants.

4-Minimum Reporting Level: the value and unit of measure at or above which the concentration or density of the

contaminant must be measured using the Approved Analytical Methods.

5-Sampling Location: the locations within a PWS at which samples must be collected.

6-Years During WhichMonitoring to Be Completed: The years during whichthe sampling and testing are to occur for

the indicated contaminant.
UCMR Reference Guide October 2001

29

The proceduresshall be done in accordance with the documents listed next in these footnotes. The incorporation by

reference of the following documents listed in footnotes b-d and l was approved by the Director of the Federal

Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of the documents may be obtainedfromthe

following sources. Information regarding obtaining these documents can be obtainedfromthe Safe Drinking Water

Hotline at 800-426-4791. Documents may be inspected at EPA’s Drinking Water Docket, 401 M Street, SW.,

Washington, DC20460 (Telephone: 202-260-3027); or at the Office of Federal Register, 800 NorthCapitol Street,

NW., Suite 700, Washington, DC.

a

 The version of the EPA methods which you must follow for this Rule are listed at §141.24(e). 

b

 Annual Book of ASTM Standards, 1996, 1998 and 1999 Vol. 11.02, American Society for Testing and Materials.

Method D5812-96, “Standard Test Method for Determination of Organochlorine Pesticides in Water by Capillary

Column Gas Chromatography”, is located in the Annual Book of ASTM Standards, 1998 and 1999, Vol. 11.02.

Methods D5790-95,“StandardTestMethodforMeasurement of Purgeable Organic Compounds inWater byCapillary

Column Gas Chromatography/Mass Spectrometry”; D5475-93, “Standard TestMethodforNitrogen- andPhosphorousContaining Pesticides in Water by Gas Chromatography with a Nitrogen-Phosphorous Detector”; and D5317-93,

“StandardTest Method for Determination of Chlorinated Organic AcidCompounds inWater by Gas Chromatography

with an Electron Capture Detector” are located in the Annual Book of ASTM Standards, 1996 and 1998, Vol 11.02.

Copies may be obtained from the American Society for Testing and Materials, 100 Barr Harbor Drive, West

Conshohocken, PA 19428. 

c

 Official Methods of Analysis of AOAC (Association of Official Analytical Chemist) International, Sixteenth

Edition, 4th Revision, 1998, Volume I, AOAC International, First Union National Bank Lockbox, PO Box 75198,

Baltimore, MD 21275-5198. 800-379-2622.

d

 SM 6210 D is only found in the 18thand 19theditions of Standard Methods for the Examination of Water and

Wastewater, 1992 and 1995, American Public Health Association; either edition may be used. SM 6200 B and 6200

Care only foundinthe 20th edition of StandardMethods for the Examinationof Water andWastewater, 1998. Copies

may be obtained from the American Public Health Association, 1015 Fifteenth Street NW, Washington, DC 20005.

e

 Minimum Reporting Level determined by multiplying by 10 the least sensitive method’s detection limit (detection

limit=standard deviation timesthe Student’s t value for 99% confidence level withn-1 degrees of freedom), or when

available,multiplying by 5 the leastsensitive method’s estimated detection limit (where the estimated detection limit

equalsthe concentration of compound yielding approximatelya 5 to 1 signal to noise ratio or the calculateddetection

limit, whichever is greater).

f

 Entry Points to the Distribution System (EPTDS), after treatment,representing each non-emergency water source

in use over the 12-month period of monitoring: this only includes entry points for sources in operation during the

months in which sampling is to occur. Sampling must occur at the EPTDS, unless the State has specified other

sampling points that are used for compliance monitoring 40 CFR 141.24 (f)(1), (2), and (3). See 40 CFR

141.40(a)(5)(ii)(C) for a complete explanation of requirements, including the use of source (raw) water sampling

points.

g

 Minimum Reporting Levels (MRL) for Volatile Organic Compounds (VOC) determined by multiplying either the

publisheddetection limit or 0.5 μg/Ltimes 10, whicheveris greater. The detection limit of 0.5 μg/L (0.0005 mg/L)

was selected to conform to VOC detection limit requirements of 40 CFR 141.24(f)(17)(E).

h

 The approved methods do not allow for the identification and quantitation of the individual acids. The single

analytical result obtained should be reported as total DCPA mono- and di-acid degradates.

i

 Method 515.3, “Determination of Chlorinated Acids in Drinking Water byLiquid-LiquidExtraction, Derivatization

and Gas Chromatography withElectronCapture Detection,” Revision 1.0 July 1996. EPA815-R-00-014, “Methods

for the Determination of Organic and Inorganic Compounds in Drinking Water, Volume 1,” August 2000. Available

from the National Technical InformationService,NTISPB2000-106981,U.S. Department of Commerce, 5285 Port

Royal Road, Springfield, Virginia 22161. The toll free number is 800-553-6847. Alternatively, the method can be

assessed and downloaded directly on-line at www.epa.gov/safewater/methods/sourcalt.html.

j

 Since EPA Method 515.3 does not include a solvent wash step following hydrolysis, the parent DCPA is not removed

priorto analysis,therefore, only non-detect datamay be reported using Method 515.3. All samples with results above

the MRL must be analyzed by one of the other approved methods.

k

 EPA Method 515.4, “Determination of Chlorinated Acids in Drinking Water by Liquid-Liquid Microextraction,

Derivatizationand Fast Gas Chromatography withElectronCaptureDetection,”Revision1.0,April2000,EPA815/B00/001. Available by requesting a copy from the EPA Safe Drinking Water Hotline within the United States at 800-

426-4791 (Hours are Monday through Friday, excluding federal holidays, from 9 a.m. to 5:30 p.m. Eastern Time).

Alternatively, the method can be assessed and downloaded directly on-line at

www.epa.gov/safewater/methods/sourcalt.html.
UCMR Reference Guide October 2001

30

l

 Method 314.0, “Determination of Perchlorate in Drinking Water Using Ion Chromatography,” Revision 1.0, EPA

815-B-99-003, November 1999. EPA 815-R-00-014, “Methods for the Determination of Organic and Inorganic

Compounds inDrinking Water, Volume 1,” August 2000. Available fromthe National Technical InformationService,

NTISPB2000-106981,U.S. Department of Commerce, 5285 Port RoyalRoad,Springfield, Virginia22161. The toll

free number is 800-553-6847. Alternatively, the method can be assessed and downloaded directly on-line at

www.epa.gov/safewater/methods/sourcalt.html.

m

 MRL was established at a concentration, which is at least 1/4th the lowest known adverse health concentration, at

which acceptable precision and accuracy has been demonstrated in spiked matrix samples.

n

 Sample preservation techniques and holding times specified in EPA Method 524.2 must be used by laboratories using

either EPA Method 502.2 or Standard Methods 6200C.

Table 8. Unregulated Contaminant Monitoring Regulation (1999) List 2

1-Contaminant

2-CAS

Registry

Number

3-Analytical

Methods

4-

Minimum

Reporting

Level

5-Sampling

Location

6-Period During

Which Monitoring

to Be Completed

List 2 - Screening Survey – Chemical Contaminants

To Be Sampled After Notice of Analytical Methods Availability

1,2-

diphenylhydrazine

122-66-7 EPA Method 

526a

0.5 μg/L EPTDSe2001 - Selected

Systems serving

<10,000 persons;

2002 - Selected

systems serving >

10,000 persons.

2-methyl-phenol 95-48-7 EPA Method

528b

1 μg/Lf EPTDSesame as above.

2,4-dichlorophenol 120-83-2 EPA Method

528b

1 μg/Lf EPTDSesame as above.

2,4-dinitrophenol 51-28-5 EPA Method

528b

5 μg/Lf EPTDSesame as above.

2,4,6-

trichlorophenol

88-06-2 EPA Method

528b

1 μg/Lf EPTDSesame as above.

Alachlor ESA Reservede Reservedd Reservedd Reservedd Reservedd

Diazinon 333-41-5 EPA Method

526a

0.5 μg/Lf EPTDSe2001 - Selected

Systems serving

<10,000 persons;

2002 - Selected

systems serving >

10,000 persons.

Disulfoton 298-04-4 EPA Method

526a

0.5 μg/Lf EPTDSesame as above.

Diuron 330-54-1 EPA Method

532c

1 μg/Lf EPTDSesame as above.

Fonofos 944-22-9 EPA Method

526a

0.5 μg/Lf EPTDSesame as above.

Linuron 330-55-2 EPA Method

532c

1 μg/Lf EPTDSesame as above.
UCMR Reference Guide October 2001

Table 8. Unregulated Contaminant Monitoring Regulation (1999) List 2

1-Contaminant

2-CAS

Registry

Number

3-Analytical

Methods

4-

Minimum

Reporting

Level

5-Sampling

Location

6-Period During

Which Monitoring

to Be Completed

List 2 - Screening Survey – Chemical Contaminants

To Be Sampled After Notice of Analytical Methods Availability

31

Nitrobenzene 98-95-3 EPA Method

526a

0.5 μg/Lg EPTDSesame as above.

Prometon 1610-18-0 EPA Method

526a

0.5 μg/Lf EPTDSesame as above.

RDX 121-82-4 Reservedd Reservedd Reservedd Reservedd

Terbufos 13071-79-9 EPA Method

526a

0.5 μg/Lf k EPTDSe2001 - Selected

Systems serving

<10,000 persons;

2002 - Selected

systems serving >

10,000 persons.

List 2 - Screening Survey – Microbiological Contaminants

To Be Sampled After Notice of Analytical Methods Availability

Aeromonas NA Reservedd Reservedd Distribution

System g

2003h

Column headings are:

1 - Chemical or microbiological contaminant: the name of the contaminants to be analyzed.

2 -CAS(Chemical AbstractServiceNumber) RegistryNumber or IdentificationNumber: a unique numberidentifying

the chemical contaminants.

3 - Analytical Methods: method numbers identifying the methods that must be used to test the contaminants.

4 - Minimum Reporting Level: the value and unit of measure at or above which the concentration or density of the

contaminant must be measured using the Approved Analytical Methods.

5 - Sampling Location: the locations within a PWS at which samples must be collected.

6 - Years During WhichMonitoring to be Completed: the years during whichthe sampling and testing are to occur for

the indicated contaminant.

The procedures shall be done in accordance with the documentslisted next in these footnotes. The incorporation by

reference of the following documents listed in footnotes a-c, was approved by the Director of the Federal Register

in accordance with5 U.S.C. 552(a) and 1 CFRpart 51. Copies of the documents may be obtained from the following

sources. Information regarding obtaining these documents can be obtained fromthe Safe Drinking Water Hotline at

800-426-4791. Copies of the documents may be obtained from the sources listed in these footnotes. Information

regarding obtaining these documents can be obtained from the Safe Drinking Water Hotline at 800-426-4791.

Documents may be inspected at EPA’s Drinking Water Docket, 401 M Street, SW., Washington, DC 20460

(Telephone: 202-260-3027); or at the Office of Federal Register, 800 North Capitol Street, NW., Suite 700,

Washington, DC.

a EPAMethod 526, “Determinationof SelectedSemivolatile Organic Compounds in Drinking Water by Solid Phase

ExtractionandCapillaryColumn Gas Chromatography/Mass Spectrometry(GC/MS),”Revision1.0,June 2000. EPA

815-R-00-014, “Methods for the Determination of Organic and Inorganic Compounds inDrinking Water, Volume 1,”

August 2000. Available from the National Technical Information Service, NTIS PB2000-106981, U.S. Department

of Commerce, 5285 Port Royal Road, Springfield, Virginia 22161. The toll free number is 800-553-6847.
UCMR Reference Guide October 2001

32

Alternatively, the method can be assessed and downloaded directly on-line at

www.epa.gov/safewater/methods/sourcalt.html.

b

 EPA Method 528, “Determination of Phenols in Drinking Water by Solid Phase Extraction and Capillary Column

Gas Chromatography/Mass Spectrometry (GC/MS),” Revision 1.0, April 2000. EPA 815-R-00-014, “Methods for

the Determination of Organic and Inorganic Compounds inDrinking Water, Volume 1,” August 2000. Available from

the National Technical InformationService,NTISPB2000-106981,U.S. Department of Commerce, 5285 PortRoyal

Road, Springfield, Virginia22161. The toll free number is 800-553-6847. Alternatively, the method can be assessed

and downloaded directly on-line at www.epa.gov/nerlcwww/ordmeth.htm. 

c

 EPA Method 532, “Determination of Phenylurea Compounds in Drinking Water by SolidPhase Extractionand High

Performance LiquidChromatography withUVDetection,” Revision 1.0, June 2000. EPA 815-R-00-014, “Methods

for the determination of Organic and Inorganic Compounds in Drinking Water, Volume 1,” August 2000. Available

fromthe National Technical InformationService,NTIS PB2000-106981,U.S. Department of Commerce, 5285 Port

Royal Road, Springfield, Virginia 22161. The toll free number is 800-553-6847. Alternatively, the method can be

assessed and downloaded directly on-line at www.epa.gov/safewater/methods/sourcalt.html. 

d

 To be specified at a later time.

e

 EntryPointsto the DistributionSystem (EPTDS), after treatment, representing each non-emergency water source

in use over the 12-month period of monitoring: this only includes entry points for sources in operation during the

months in which sampling is to occur. Sampling must occur at the EPTDS, source water sampling points are not

permitted for List 2 contaminant monitoring.

f

 Minimum Reporting Level represents the value of the lowest concentration precision and accuracy determination

made duringmethods development and documentedin the method. If method options are permitted, the concentration

used was for the least sensitive option.

g

 Three samples must be taken from the distribution system, which is owned or controlled by the selected PWS. The

sample locations must include one sample from a point (MD from §141.35 (d)(3), Table 1) where the disinfectant

residual is representative of the distribution system. This sample location may be selected from sample locations

which have been previously identified for samples to be analyzed for coliform indicator bacteria. Coliform sample

locations encompass a variety of sites including midpoint samples which may contain a disinfectant residual that is

typical of the system. Coliform sample locations are described in 40 CFR 141.21. This same approach must be used

for the Aeromonas midpoint sample where the disinfectant residual wouldnot have declined and wouldbe typical for

the distribution system. Additionally, two samples must be takenfromtwo different locations: the distal or dead-end

location in the distribution system(MRfrom§141.35 (d)(3),Table1),avoidingdisinfectant boosterstations,and from

alocationwhereprevious determinations have indicatedthe lowest disinfectant residual inthe distributionsystem(LD

from §141.35(d)(3), Table 1). If these two locations of distal and low disinfectant residual sites coincide, then the

second sample must be taken at location between the MD and MR sites. Locations in the distribution system where

the disinfectant residual is expectedto be loware similar to TTHMsampling points. Sampling locations for TTHMs

are described in 63 FR 69468.

h

 This monitoring period is contingent upon promulgation of the analytical method and minimum reporting level.

5.3 Quality Control Requirements for Sample Collection

Procedures for sample collection under the UCMR are contaminant- and method-specific. Detailed

sample collection instructions for Assessment Monitoring contaminants can be found in the Small

Systems Guidance – Unregulated Contaminant Monitoring Regulation Guidance for Operators of

Public Water Systems Serving 10,000 or Fewer People (EPA 815-R-01-002) – for small PWSs, and

in the UCMR (1999) List 1 and List 2 Chemical Analytical Methods QC Manual (EPA 815-R-01-

028), for large systems and laboratories. 

Both large and small PWSs must ensure that samples are collected early enough in the day to allow

time for overnight delivery to the laboratories,since some samplesmustbe processed within30 hours

of collection (§141.40(a)(5)(i)(a)). Samples may not be composited (i.e., combined, mixed, or

blended). Each sample must be collected, preserved (if applicable), and tested separately

(§141.40(a)(5)(i)(b)). 
UCMR Reference Guide October 2001

33

5.3.1 Quality ControlRequirementsfor Sample Collection: Additional Requirements Specific

to Large Systems

If sample collection at large systems is not performed according to the required instructions and

procedures for each contaminant and analytical method, the systemowner/operator will be required

to resample following the required method instructions and procedures (§141.40(a)(5)(ii)(F) and

(iii)(C)). If laboratory or shipping problems cause the loss of a sample, then all efforts should be

made to replace thatsample atthe earliestpossible time (preferablyinthe same month thatthe original

sample was collected). If resampling in the same month is not possible, then systems should collect

the samples in the same quarter, so that monitoring schedules do not need to change. The only case

where monitoring schedules may change is if all the samplesfor the firstsampling period are lost or

damaged. In this case, the system may monitor in another month, and reschedule sampling based on

that starting month. 

Large system owners/operators are responsible for arranging contaminant analysis for Assessment

Monitoring and Screening Surveys at an approved laboratory. For the Pre-Screen Testing analyses,

the EPA will provide a list of laboratories that may be used when pre-screen testing is required.

The large system owner/operator should consult with the laboratory conducting the analytical work

regarding the sampling protocol (§141.40(a)(5)(iii)(F)). Laboratories may require collection and

submission of some duplicate samples as part of their internal quality control program, or for other

practical considerations in the event that sample containers are lost, broken, or not properly sealed

or cooled. 

5.3.2 Quality ControlRequirementsfor Sample Collection: Additional Requirements Specific

to Small Systems

The State or EPA may notify smallsystems oftheirsampling requirements and schedule. If sampling

is not performed according to the instructions or proceduresfor each contaminant and its method, then

the owner/operator must notify the State or EPA ofthe sampling deviations. The sampling deviations

should be included in the sample reporting forms that are sent back to the laboratorywith the samples.

The PWS must resample as soon as instructions are received from the laboratory or the EPA

contractor (§141.40(a)(5)(iii)(C)).

The EPA contractor will send a sample collection kit to all small systems, which will include: an

insulated sample shipping container or containers; all required sampling bottles;freeze packsto keep

samples cool in transit back to the laboratory; any chemicals needed to dechlorinate and/or preserve

samples; a pre-paid return shipping docket; sample collection data forms; and any additional

instructions or materials needed for sample collection, dechlorination, and preservation. If any of the

materials listed in the kit instructions are not included or arrive damaged, the system must notify the

contractor prior to use of the sample collection kit (§141.40(a)(5)(iii)(D)). Each kit must be stored

and maintained in a secure place until used forsampling (§141.40(a)(5)(iii)(D)). Note that cold packs

must be frozen prior to sample collection so thatthe collected samples canbe keptcool when shipped

to the laboratory (§141.40(a)(5)(iii)(E)).

Instructions provided with the kit will describe the proper procedures for use of containers, sample

collection, dechlorination and/or preservation ofthe samples, and sealing and preparing the samples

and containers for shipment. EPA will use a random process to select some systems in State

Monitoring Plans (SMPs) that will be requested to collect duplicate samples for quality control.
UCMR Reference Guide October 2001

34

Approximately 10% ofsamples collected for small systems will be collected in duplicate. Systems

selected for this quality control sampling will receive two sample collectionkits. The same required

sampling procedures must be used for both the original and the duplicate sample kits

(§141.40(a)(5)(iii) (D) and (F)). These systems will not incur additional costs since EPA is paying

for small system testing. 

5.3.3 Quality Control Requirements for Laboratories

Systems must ensure thatlaboratories providing services in support of their monitoring are currently

certified to perform compliance monitoring, as applicable to those analytical methods which are

approved for UCMR Assessment Monitoring and Screening Surveys (§141.40(a)(5)(ii)(G). They

must also ensure that the laboratory performing perchlorate and Aeromonas analyses has passed the

EPA Performance Evaluation requirements. These methods specify quality control procedures that

must be followed to ensure reliable data. Detailed monitoring quality control procedures are

discussed in the UCMR (1999) List 1 and List 2 Chemical Analytical Methods QC Manual (QC

Manual, EPA 815-R-01-028). 

Quality control procedures and the frequency of quality control testing vary among the different

analyticalmethods used for laboratory analysis ofthe UCMRcontaminants. Many methods specified

in the UCMR provide criteria to be used in evaluating and accepting laboratory performance based

onrelated quality control data. It is imperative that laboratories adhere to the specified quality control

requirements. UCMR monitoring data will not be accepted by EPA if the applicable quality control

requirements are notmet. If the UCMRquality control requirements are notmet, then the systemwill

be out of compliance with respect to the UCMR. The laboratory should ensure that PWSs resample

when quality control requirements are notmet. Detailed information on all laboratory quality control

requirements are specified in Appendix A of §141.40 and the QC Manual.

5.3.4 Additional Quality Controls

Samples for which the methods specify storage at approximately 4°C must arrive at the laboratory

packed in coolers with ice or frozen cold packs. If there is no visible ice or the cold packs are

completely thawed, the laboratory should report the conditions to the water system. Samples should

not be analyzed if the shipping temperature was not maintained at 4°C (± 2°). The laboratory must

also invalidate samples that were collected in improper sampling containers (e.g., plastic bottles,

where the method requirements specify glass) or thatwere improperly filled (e.g., half-filled bottles

for samples that are required to be completely filled with no air or bubbles). New water samples

should be collected to replace these samples. If resampling cannot be performed, then the water

system must indicate in the report to EPA that the samples were invalidated because of a shipment,

storage, or sampling problem, etc., and no data should be reported.

In addition, the laboratory must analyze each sample within the required holding time (§141.40

Appendix A (1)). When appropriate, EPA standardized the holding times across analytical methods

for the same analyte group, except for Perchlorate, which has a holding time of approximately 40

hours. Please refer to the QC Manual (EPA 815-R-01-028) for more detailed informationonsample

holding times. If a UCMR sample is not extracted or analyzed within the specified holding time, then

the data forthe sample should notbe reported. The laboratory should indicate to the water system that

the sample was invalidated because of a holding time problem, and the systemshould collect another

sample. This information would then be reported when the system submits its report for that sampling

period.
UCMR Reference Guide October 2001

35

6. UCMR Reporting Requirements

6.1 Data Elements

Large systems are required by the UCMR to ensure that the information listed in Table 9 is reported

to the EPA within 30 days following the month in which laboratory results were received

(§140.35(d)). Laboratories will post UCMR results for their client public water systems by uploading

or entering the data elements using EPA’s electronic reporting system. Analytical results must be

approved by PWSs and then released to the EPA as officially reported UCMR data.

Smallsystems should check that the pre-printed information provided on the sampling forms is correct.

This information must be reported so that each sampling point used for UCMR sampling can be

associated with the facility(ies) in use at the time the sampling occurred (§141.40(a)(5)(iii)(E)). 

In addition, systems must provide points of contact for: a PWS technical person who is responsible

for the technical aspects of UCMR activities, such as details concerning sampling and reporting; an

official UCMRspokesperson from the PWS; and a laboratory contact personwho is able to address

questions concerning the analyses performed by the laboratory (§141.40(d)(1)). The laboratory will

post the monitoring data to EPA’s internet-based SDWARS/UCMR (Safe Drinking Water Accession

and Review System) reporting system (§141.35(e) and (f)). 

Table 9. UCMR Reporting Requirements

Data Element Definition

1. Public Water System

Identification Number

The code used to identify each PWS. The code begins with the

standard two-character postal State abbreviation; the remaining seven

characters are unique to each PWS.

2. Public Water System Facility

Identification Number -

Sampling Point Identification

Number and Sampling Point Type

Identification

The Sampling point identification number and sampling point type

identification must either be static or traceable to previous numbers

and type identifications throughout the period of unregulated

contaminant monitoring. The Sampling point identification number is

a three-part alphanumeric designation, made up of:

a. The Public Water System Facility Identification Number is an

identification number established by the State, or at the State’s

discretion the PWS, that is unique to the PWS for an intake for each

source of water, a treatment plant, a distribution system, or any other

facility associated with water treatment or delivery and provides for

the relationship of facilities to each other to be maintained; 

b. The Sampling Point Identification Number is an identification

number established by the State, or at the State’s discretion the PWS,

that is unique to each PWS facility that identifies the specific sampling

point and allows the relationship of the sampling point to other

facilities to be maintained; and

c. Sampling Point Type Identification is one of following:

SR - Untreated water collected at the source of the water system

facility.
UCMR Reference Guide October 2001

Table 9. UCMR Reporting Requirements

Data Element Definition

36

EP - Entry point to the distribution system.

MD - midpoint in the distribution system where the disinfectant

residual would be expected to be typical for the system such as the

location for sampling coliform indicator bacteria as described in 40

CFR 141.21.

MR - point of maximum retention is the point located the furthest

from the entry point to the distribution system which is approved by

the State for trihalomethane (THM) (disinfectant byproducts (DBP))

and/or total coliform sampling.

LD - location in the distribution system where the disinfectant 

residual is the lowest which is approved by the State for THM (DBP)

and/or total coliform sampling.

3. Sample Collection Date The date the sample is collected reported as 4-digit year, 2-digit

month, and 2-digit day.

4. Sample Identification Number An alphanumeric value of up to 15 characters assigned by the

laboratory to uniquely identify containers or groups of containers

containing water samples collected at the same time and sampling

point.

5. Contaminant/Parameter The unregulated contaminant or water quality parameter for which the

sample is being analyzed.

6. Analytical Results - Sign An alphanumeric value indicating whether the sample analysis result

was: 

a. (<) “less than” means the contaminant was not detected or was

detected at a level “less than” the minimum reporting level (MRL).

b. (=) “equal to” means the contaminant was detected at a level “equal

to” the value reported in “Analytical Result - Value.” 

7. Analytical Result - Value The actual numeric value of the analysis for chemical and

microbiological results, or the MRL if the analytical result is less than

the contaminant’s MRL

8. Analytical Result - Unit of

Measure

The unit of measurement for the analytical results reported. [e.g.,

micrograms per liter, (μg/L); colony-forming units per 100 milliliter,

(CFU/100 mL), etc.]

9. Analytical Method Number The identification number of the analytical method used.

10. Sample Analysis Type The type of sample collected. Permitted values include:

a. RFS - Raw field sample - untreated sample collected and submitted

for analysis under this rule.

b. RDS - Raw duplicate field sample - untreated field sample duplicate
UCMR Reference Guide October 2001

Table 9. UCMR Reporting Requirements

Data Element Definition

37

collected at the same time and place as the raw field sample and

submitted for analysis under this rule.

c. TFS - Treated field sample - treated sample collected and submitted

for analysis under this rule.

d. TDS - Treated duplicate field sample - treated field sample duplicate

collected at the same time and place as the treated field sample and

submitted for analysis under this rule.

11. Sample Batch Identification

Number

The sample batch identification number consists of three parts:

a. Up to a 10-character laboratory identification code assigned by

EPA;

b. Up to a 15-character code assigned by the laboratory to uniquely

identify each extraction or analysis batch. 

c. The date that the samples contained in each extraction batch

extracted or in an analysis batch were analyzed, reported as an 8-digit

number in the form 4-digit year, 2-digit month, and 2-digit day.

12. Minimum Reporting Level MRL refers to the lowest concentration of an analyte that may be

reported. Unregulated contaminant monitoring MRLs are established

in §141.40 monitoring requirements for unregulated contaminants.

13. Minimum Reporting Level Unit

of Measure

The unit of measure to express the concentration, count, or other

value of a contaminant level for the Minimum Reporting Level

reported. 

(e.g., μg/L, colony forming units/100 mL (CFU/100 mL), etc.).

14. Analytical Precision Precision is the degree of agreement between two repeated

measurements and is monitored through the use of duplicate spiked

samples. For purposes of the Unregulated Contaminant Monitoring

Regulation (UCMR), Analytical Precision is defined as the relative

percent difference (RPD) between spiked matrix duplicates. The RPD

for the spiked matrix duplicates analyzed in the same batch of samples

as the analytical result being reported is to be entered in this field. 

Precision is calculated as the RPD of spiked matrix duplicates from

the mean using:

 RPD = absolute value of [(X1 - X2) /{(X1 +X2)/2}] x 100%

where:

X1 is the concentration observed in spiked field sample minus the

concentration observed in unspiked field sample

X2 is the concentration observed in duplicate spiked field sample

minus the concentration observed in unspiked field sample

15. Analytical Accuracy Accuracy describes how close a result is to the true value measured
UCMR Reference Guide October 2001

Table 9. UCMR Reporting Requirements

Data Element Definition

38

through the use of spiked field samples. For purposes of unregulated

contaminant monitoring, accuracy is defined as the percent recovery

of the contaminant in the spiked matrix sample analyzed in the same

analytical batch as the sample result being reported and calculated

using:

% recovery = [(amt. found in spiked sample - amt. found in sample) /

amt. spiked] x 100% 

16. Spiking Concentration The concentration of method analytes added to a sample to be analyzed

for calculating analytical precision and accuracy where the value

reported use the same unit of measure reported for Analytical Results

17. Presence/Absence Reserved

6.2 Electronic Reporting and Data Review

The UCMRrequires that all data be reported electronicallyto EPA, unless a request is received from

the PWS. Further guidance and tutorials is provided in the UCMR Reporting Guidance (EPA815-R01-029) and in the forthcoming Implementation Guide for UCMR. The UCMR provides for

electronic reporting of UCMR data directly from laboratories on behalf ofsystems. This is intended

to facilitate “one-entry” of data, reducing reporting errors and reducing the time involved in

investigating, checking and correcting errors at all levels (laboratory, system, State, and EPA). The

reporting process will be secure. PWSs and laboratories will have to register as users of EPA’s

Central Data Exchange (CDX) before gaining access to EPA’s electronic reporting Web site.

Registration began in March 2001. Systems will have to approve their data before it is available to

EPA. 

In general, a PWS can fulfill its responsibilities in one oftwo ways: (1) it can instruct the laboratory

to post the monitoring resultsto SDWARS/UCMRdatabase through the CDX,so the PWS can review

the data on line and electronically indicate its approval to make the data available to EPA; or (2) it

can elect to receive a hard copy ofthe monitoring results for review and then indicate its approval to

the laboratory to upload the data to EPA (however, the PWS, or its representative, will still have to

provide electronic approval within SDWARS/UCMR, to provide EPA access to the data). The PWS

must also submit the results to the State, and is responsible for ensuring compliance with any other

State reporting requirements. 

EPA is developing several options for the electronic reporting by laboratories, including the

capability to upload data in electronic batches or individually using a Web interface where data can

be keyed in using “web forms”. Laboratories that have good electronic reporting capabilities and

want or need to upload large batches of data have two options: 

• Standard flat file format – such as tab or comma delimited files, or

• New XML or extensible mark-up language format – protocol and format are currently being

finalized, and may be available through CDX. 
UCMR Reference Guide October 2001

39

Large systems are responsible for reviewing analytical results and reporting the results to the EPA

(with a copy to the State) within 30 days following the month in which the results are received from

the laboratoryasspecified in 40 CFR §141.35. However, for small systems, laboratories will report

all analytical results to EPA, and the EPA contractor will review all sampling results. For example,

if analytical results for samples that were collected during October were notreceived back fromthe

laboratory until November, the latest allowable reporting date would be December 30. All systems

are responsible for ensuring timely reporting within, or shortly following the monitoring period.

EPA hasmade anexceptionto the normal reporting schedule for the firstrounds of monitoring in 2001

to allow for the readiness ofthe electronic reporting system. Systems which receive results prior to

January 1, 2002 will be required to report their data by April 30, 2002. EPA will then hold the data

for 60 days to allow for quality control review and for review by systems and States. EPA will then

place the data in the National Drinking Water Contaminant Occurrence Database (NCOD) at the time

of the next database update. 

For small systems, EPA will send copies of monitoring results to the systems and the State once EPA

receives and validates the results fromthe contract laboratories. Small systems are still responsible

for enduring that their State receives a copy ofthe results. Participating small systems will have 30

days to review and comment on the data. Systems and States will have an additional 60 days to

review the data before results are reported to the NCOD. 

Since States will have electronic access to the monitoring results for systems in their State, theymay

allow systems to forgo the requirement to provide them with a copy of the results. Systems should

check with their States for any additional reporting requirements beyond the scope of the UCMR

requirements(i.e.,some Statesmayrequire immediate reporting ofmonitoring results whichmaypose

an imminent danger to human health). EPA encouraged States to notify PWSs of additional Statespecific reporting requirements when they notify PWSs of their responsibilities under the UCMR.

Systems that do not receive direction from their States should report results to their State Agency

concurrent with reporting results to EPA through the electronic reporting system. For small systems

in States that require immediate reporting of contaminants detected, EPA will report results to the

system and the State after EPA receives and validates the results from the laboratory. However, the

system is still responsible for enduring that the State receives a copy of the results. EPA is also not

responsible foridentifying all ofthe Statesthatrequire immediate reporting of detected contaminants.

6.3 Public Notification

CWSs must report UCMR results through the Consumer Confidence Report (CCR) Rule, published

on August 19, 1998 (63 FR 44511), as required by §141.153(d). CWSs must report UCMR results

when any of the UCMR contaminants are detected. CCRs must be sent to all billing customers each

year by July 1. A system may briefly explain in the CCR why it is monitoring for unregulated

contaminants. The explanation may read as follows: 

Unregulated contaminants are those for which EPA has not established drinking water

standards. The purpose of unregulated contaminant monitoring is to assist EPA in

determining the occurrence of unregulated contaminants in drinking water and whether

future regulation is warranted.

For all PWSs that are subject to the Rule, UCMR monitoring results will be made available to the

public through the requirements ofthe Public Notification Rule (May 4, 2000 at 65 FR 25982). All
UCMR Reference Guide October 2001

40

PWSs are required to notify the public annually of the availability of unregulated contaminant

analytical results. Failure to monitor for unregulated contaminants, as required through the UCMR,

will also be reportable under the Public Notification Rule. Because the effective date of the revised

public notification rule differs by State, PWS owners and operators should check with their State

drinking water agency to determine the applicable public notice requirements. Detailed information

on these reporting requirements can be found in the documents Preparing Your Drinking Water

ConsumerConfidence Report(EPA816-R-99-002) and PublicNotification Handbook (EPA 916-R00-010). Both of these documents are available on the Web at www.epa.gov/safewater. 

The results thatwill be reported through the CCR and Public Notification Rules should be based on

the same monitoring data thatthe States and EPAwill receive under the UCMR. Information received

by EPA will be available to the public via NCOD. Unregulated contaminants not on the UCMR List

would not be required to be reported under the CCR. However, any emerging contaminants oflocal

or State concern may be voluntarily reported to the NCOD to assist EPA in determining if these

contaminants should be considered for establishing health-based standards or advisories.
UCMR Reference Guide October 2001

41

7. State Responsibilities

7.1 State Plan Development

States play a very important role in the UCMR program by entering into Partnership Agreement s

(PAs) with EPA to facilitate State participation and implementation, and/or by reviewing the State

Monitoring Plan(SMP). The SMP played a critical role in UCMR implementation by allowing States

to: identify which small systems will participate in Assessment Monitoring (List 1); identify which

systems will participate in the Screening Surveys (List 2); and specify various aspects of the timing

and location of system monitoring.

All States (regardless of whether or not they entered into a PA with EPA) were asked to review the

initial SMPs for their State. Review of the SMP included ensuring that small systems selected to

participate in the UCMR were active and did not purchase all of their water. States were asked to

replace ineligible systems with one of the two replacement systems that EPA identified for each

“primary” systemselected to monitor for the UCMR. In the SMPs, States were also asked to review

inventory information as well as the timing and location of sampling. States were also asked to

review the large system information for those that were selected to conduct Screening Surveys to

ensure that these systems were eligible to conduct the Screening Surveys. Detailed information on

SMP review and modification may be found in the Initial and Final State Plans which EPA sent to

each participating State.

7.2 Partnership Agreements

During the UCMR rulemaking process, States suggested that EPA use a Memorandum of Agreement

(which is represented by the PA) rather than the formal adoption ofrules and revisions ofeach State’s

primary enforcement responsibility (primacy) program to allow States to participate in UCMR

implementation. PAs serve as a key implementation mechanism for the UCMR by identifying and

assigning responsibility for important activities thatmust be conducted to successfully implement the

UCMR. States that entered into an Agreement with EPA are generally responsible for reviewing and

updating their SMPs, and notifying small and large systems of their Assessment Monitoring and

Screening Survey responsibilities prior to scheduled sampling. In general, these States also provide

smallsystems with instructions (prepared byEPA) on the location, frequency, and timingofsampling.

The EPA contractor will provide small systems with instructions on the use of sampling equipment,

and handling and shipment of samples.

States that entered into a PA and who have agreed to identify vulnerable systems for Pre-Screen

Testing are responsible for notifying the PWS owners/operators of Pre-Screen Testing requirements

at least 90 days before sampling must occur. States with an Agreement may also be responsible for

specifying the latitude and longitude of PWS treatment plants by the time ofthe system’sreporting of

Assessment Monitoring results to the NCOD. 

Most States agreed to review and modify their SMPs, including modifying the vulnerable time for

sampling, reviewing monitoring dates for systems, and specifying alternate dates if appropriate, and

identifying alternate sampling points for small PWSs as needed. Note that many States which did not

enter into PAs with EPA modified and reviewed the SMPs for their State.

Other responsibilities some States agreed to accomplish through the PA process included updating

EPA’s Safe Drinking Water InformationSystem(SDWIS) based on PWS inventory changes, ensuring

that each PWS facility has an unique identification number, and providing EPA with a list of certified
UCMR Reference Guide October 2001

42

laboratories in the State. Some States have also agreed to collect Assessment Monitoring and

Screening Survey samples for small systems and/or IndexSystem(s)selected to monitor in the State.

Some States have also agreed to review UCMR data (in accordance with §141.35(b)) before EPA

places data in the NCOD. Some States agreed to assist in obtaining system compliance through

follow-up contact with systems regarding their monitoring responsibilities once informed of system

non-compliance as provided for in §141.40(a)(8) and (b)(1)(v), (vi), (vii) and (viii). 

Note that not all States are responsible for performing all ofthe activities identified above. A State’s

actual responsibilities are outlined in the PA as discussed and agreed to by the State and EPA. For

some States, EPA is responsible for performing some of the activities outlined above.

7.3 State Waivers for Contaminants Monitored at Large Systems

States may apply to EPA for a waiver from monitoring requirements for specific contaminants for

large systems. To apply for a waiver, States must submit the following to EPA (§141.40(b)(4)):

• a list of the contaminants for which waivers are requested; and

• supporting documentation that demonstrates that each contaminant for which a waiver is

requested:

– has not been detected in the source waters or distribution systems in the State (and this

presumesthatmonitoring has beenconducted)inthe 15 years prior to the applicationdate,

and

– has never been used, stored, disposed, or released in the State in the 15 years prior to the

application date. 

If the State can demonstrate that any contaminant meets these criteria, EPA may grant a waiverfor that

contaminant.

7.4 Governors’ Petition to Add Contaminants to the Monitoring List

States may also petition EPA to add one or more contaminants to the unregulated contaminant

monitoring list. This petition must be signed by the governors of at least seven States and must clearly

identify the reason(s) for adding the contaminant to the monitoring list, including:

• the potential public health risk (particularly any information thatmight be available regarding

disproportionate risks to the health and safety of children);

• the expected occurrence (including any available data);

• any analytical methods that are known or could be used to test for the contaminant(s); and

• any other information that could assist EPA in determining whether the addition of the

contaminant(s) would preclude the listing of another contaminant of a higher public health

concern (§141.40(b)(3)).
UCMR Reference Guide October 2001

43

8. Participation of Tribal Public Water Systems

EPA Regional offices will work closely with Tribal water systems in their Region to successfully

implement the UCMR. EPA Regions were asked to work with the Tribes in reviewing the systems

selected to monitorforthe UCMRas identified in the Monitoring Plan for Tribal water systems. Note

that, forthe selectionofa national representative sample ofsmall systems, all Tribes acrossthe nation

were grouped together (i.e., treated as one State) to ensure that at least two tribal water systems were

selected to monitor for the UCMR. During the selection process, seven small tribal systems were

selected to monitor for UCMR contaminants. No large tribal systems were selected to conduct

Screening Surveys. 

With respect to Tribal monitoring, the UCMRprogramwas designed to share the responsibilities for

unregulated contaminant monitoring between the EPA Regions and the selected Tribal systems. The

EPA Regions will serve as a principal line of communication with the Tribes on UCMR issues. In

concert with the Tribal systems, the EPA Regions will coordinate the identification and assignment

of responsibilities for important activities that should be conducted to successfully implement the

UCMR during the five-year implementation cycle for Tribal water systems. Thus, cooperation and

dialogue between the EPA Regions and Tribes will be required in determining mutually agreed upon

responsibilities,suchas the review ofsysteminventory information, sample collection, and shipment

of sample kits to an approved laboratory.

8.1 Tribal Monitoring Plan Development

EPA Regions were asked to review the table of Tribal systems that were selected to monitor for the

UCMR, and to ensure that the selected systems were active and did not purchase all of their water

from another water system. EPA Regions were also asked to review and modify, if necessary, any

inventory information provided in the Tribal system Monitoring Plan. If selected systems were not

eligible to monitor for the UCMR, EPA Headquarters selected a replacement system from the list of

alternate tribal systems. Because Tribal systems were selected on a national basis, an ineligible

Tribal water system was not necessarily replaced with another system from the same EPA Region.

After finalization of the Monitoring Plan, the EPA Regions were responsible for notifying their

appropriate Tribal systems in the Monitoring Plan of their responsibilities under the UCMR

(§141.40(b)(1)(v)). 

8.2 Sample Collection Responsibility

Some EPA Regions and Tribal environmental office contacts plan to conduct the sampling at the small

tribal PWSs to ensure the quality of the data collected under the UCMR. In the case of the Tribal

water systems, the responsibility for this activity is delegated to the EPA Regions whose systems are

included in the sample of primaryTribal water systems (Regions 5, 6, 7, 8, and 9). Tribal assistance

with sample collection is an important contribution which helps provide EPA with the best data

possible for decision making. 
UCMR Reference Guide October 2001

44
UCMR Reference Guide October 2001

45

9. EPA Responsibilities

EPA Headquarters (primarily the Technical Support Center (TSC)) will directly implement the

UCMR, with implementation and coordination assistance from EPA Regional contacts, the States,

Territories, and Tribes. EPA is responsible for providing implementation guidance documents for

systems, States, and EPA Regions. EPA will provide additional ongoing assistance as needed. 

9.1 Partnership Agreements and State Monitoring Plan Development

EPA and the Association of State Drinking Water Administrators (ASDWA) drafted the Model

Partnership Agreements for use by EPA in coordinating UCMR implementation responsibilities

between the EPA Regions and the States. EPA Regions also worked closely with States in

establishing mutually-agreed-upon responsibilities in the PAs. EPA Headquarters developed initial

SMPs by selecting the national representative sample of small systems and providing detailed

instructions on review and update ofthe initial SMPs. EPA was responsible for incorporating State

modifications to SMPs and returning Final SMPs to States once all modifications were complete. 

9.2 Sample Collection and Analysis 

The TSC has contracted with a sample coordination contractor and with laboratories which will

perform all sample analyses for small systems under the UCMR. EPA is providing these contractors

with the information needed for scheduling sampling analysis. EPA will pay for the costs associated

with shipping samples fromsmall PWSsto the contract laboratories and with sampling analysis. The

EPA contract laboratories will then report the results electronically to EPA for the small systems via

the EPA web data entry form discussed in Section 6. 

EPA, its contractors, and some States will assist with collecting all of the Assessment Monitoring

samplesforIndexSystems in each year ofthe five-year monitoring cycle. However, all large systems

and all other small systems are expected to collect their own Assessment Monitoring, Screening

Survey, and Pre-Screen Testing samples. However, some States have committed to collecting

samples for the small systems in their State. 

9.3 Reviewing Analytical Results and Reporting Requirements

EPA has recently unveiled a web-based reporting database where laboratories will electronically

report UCMR results. For quality assurance, EPA will review all UCMR data before the data are

uploaded to the NCOD. All UCMR data will be made available to the public through the NCOD.

EPA will maintain the UCMR database, and will assist States with compliance tracking for the

UCMR, if requested. Refer to Section 6 for a more detailed description of system reporting

requirements.
UCMR Reference Guide October 2001

46
UCMR Reference Guide October 2001

47

10. Contact Information

For further information on this guidance document, PWSs should contact their State drinking water

agency, the appropriate EPA Region, or the Safe Drinking Water Hotline. Small PWSs, States, or

Regions with questions on small system sampling kits should contact the UCMR Implementation

Support Contractor (listed below). Large PWSs should contact the Safe Drinking Water Hotline.

State drinking water agencies with questions on this guidance should contact their appropriate EPA

Region coordinator, or the UCMR Implementation Team Leader listed below.

EPA UCMR Implementation Team Leader:

Daniel Hautman, Technical Support Center, Standards and Risk Management Division, Office of

Ground Water and Drinking Water (143), 26 West Martin Luther King Jr. Dr., Cincinnati, OH

45268. (513) 569-7274.

EPA UCMR Implementation Support Contractor:

RobinSilva-Wilkinson, GreatLakesEnvironmentalCenter(GLEC), 739 Hastings Street, Traverse

City, MI 49686. (231) 941-2230.

Supplementary Information: 

Regional Contacts

I. Chris Ryan, 1 Congress Street, 11th Floor, Boston, MA 02118. 

Phone: (617) 918-1567.

II. Robert Poon, 290 Broadway, Room 2432, New York, NY 10007-1866. 

Phone: (212) 637-3821.

III. Michelle Hoover, 1650 Arch Street, Philadelphia, PA 19103-2029. 

Phone: (215) 814-5258.

IV. Janine Morris, Sam Nunn Federal Center, 61 Forsyth St, SW, Atlanta, GA 30303. 

Phone: (404) 562-9480.

V. Janet Kuefler, 77 West Jackson Blvd., Chicago, IL 60604-3507. 

Phone: (312) 886-0123.

VI. Andrew J. Waite, 1445 Ross Avenue, Suite 1200, Dallas, TX 75202.

Phone: (214) 665-7332.

VII. Stan Calow, 901 N. Fifth Street, Kansas City, KS 66101.

Phone: (913) 551-7410.

VIII. Rod Glebe, One Denver Place, 999 18th Street, Suite 500, Denver, CO 80202.

Phone: (303) 312-6627.

IX. Jill Korte, 75 Hawthorne Street, San Francisco, CA 94105.

Phone: (415) 744-1853.

X. Gene Taylor, 1200 Sixth Avenue, Seattle, WA 98101.

Phone: (206) 553-1389.
UCMR Reference Guide October 2001

48
UCMR Reference Guide October 2001

49

APPENDICES

1. Appendix A: Acronym List

2. Appendix B: Definitions

3. Appendix C: Number of Small Systems in Representative Sample, by

State
UCMR Reference Guide October 2001

50
UCMR Reference Guide October 2001

A - 1

Appendix A — Acronym List

2,4-DNT - 2,4-dinitrotoluene

2,6-DNT - 2,6-dinitrotoluene

4,4'-DDE - 4,4'-dichloro dichlorophenyl ethylene, a degradation product of DDT

AOAC - Association of Official Analytical Chemists 

APHA - American Public Health Association

ASDWA - Association of State Drinking Water Administrators

ASTM - American Society for Testing and Materials

CAS - Chemical Abstract Service

CCL - Candidate Contaminant List

CCR - Consumer Confidence Reports

CDX - Central Data Exchange

CFR - Code of Federal Regulations

CFU/100 mL - colony forming units per 100 milliliters

CWS - community water system

DBP - disinfection byproducts

DCPA - dimethyl tetrachloroterephthalate, chemical name of the herbicide dacthal

DDT - dichloro diphenyl trichloroethane, a general insecticide

EP - entry point

EPA - Environmental Protection Agency

EPTC - s-ethyl-dipropylthiocarbamate, an herbicide

EPTDS - Entry Point to the Distribution System

ESA - ethanesulfonic acid, a degradation product of alachlor

FR - Federal Register

GLI method - Great Lakes Instruments method

LD - lowest disinfectant residual

MD - midpoint of the distribution system

mg/L - milligrams per liter

MR - maximum residence time in the distribution system

MRL - minimum reporting level

MTBE - methyl-tert-butyl-ether, a gasoline additive

NCOD - National Drinking Water Contaminant Occurrence Database

NERL - National Environmental Research Laboratory

NTIS - National Technical Information Service

NTNCWS - non-transient non-community water system

OGWDW - Office of Ground Water and Drinking Water
UCMR Reference Guide October 2001

A - 2

PA - Partnership Agreement

PWS - Public Water System

QC - quality control

RDS - raw duplicate sample 

RDX - hexahydro-1,3,5-trinitro-1,3,5-triazine

RFS - raw field sample

RPD - relative percent difference

SDWA - Safe Drinking Water Act

SDWARS - Safe Drinking Water Accession and Review System

SDWIS - Safe Drinking Water Information System

SM - Standard Methods

SMP - State Monitoring Plan

SR - source/raw water sampling point, prior to treatment

TDS - treated duplicate sample

TFS - treated field sample

TSC - Technical Support Center

TNCWS - transient non-community water system

TTHM - Total Trihalomethane

UCMR - Unregulated Contaminant Monitoring Regulations/Rule

μg/L - micrograms per liter

VOC - volatile organic compound

WQP - water quality parameter
UCMR Reference Guide October 2001

B - 1

Appendix B — Definitions

Assessment Monitoring means sampling, testing, and reporting of listed contaminants that have available

analytical methods and for which preliminary data indicate their possible occurrence in drinking water.

Assessment Monitoring will be conducted for the UCMR (1999) List 1 contaminants.

Index Systems means a limited number of small CWSs and NTNCWSs, selected from the Assessment

Monitoring systems in State Plans, that will be required to provide more detailed and frequent monitoring for

the UCMR (1999) List 1 contaminants (§141.40(a)(6)). In addition to the reporting information required for

Assessment Monitoring, the Index Systems must also report information on PWS operating conditions (such

as water source, pumping rates, and environmental setting) (§141.40(a)(6)). These PWSs must monitor each

year of the 5-year UCMR cycle, with EPA paying for all reasonable monitoring costs (§141.40(a)(4)(i)(A)).

Listed contaminant means a contaminant identified as an analyte in Table 1, 141.40(a)(3) of the UCMR. To

distinguish the current 1999 UCMR listed contaminants from potential future UCMR listed contaminants, all

references to UCMR contaminant lists will identify the appropriate year in parentheses immediately following

the acronym UCMR and before the referenced list. For example, the contaminants included in the UCMR

(1999) List include the component lists identified as UCMR (1999) List 1, UCMR (1999) List 2 and UCMR

(1999) List 3 contaminants.

Listing cycle means the 5-year period for which each revised UCMRlistis effective and during which no more

than 30 unregulated contaminants from the list may be required to be monitored.

Monitored systems means all community water systems serving more than 10,000 people, and the national

representative sample of community and non-transient non-community water systems serving 10,000 or fewer

people that are selected to be part of a State Plan for the UCMR.

Monitoring (as distinct from Assessment Monitoring) means all aspects of determining the quality of drinking

water relative to the listed contaminants. These aspects include drinking water sampling and testing, and the

reviewing, reporting, and submission to EPA of analytical results.

Most vulnerable systems (or Systems most vulnerable) means a subset of 5 to not more than 25 PWSs of all

monitored PWSs in a State that are determined by that State in consultation with the EPA Regional Office to

be most likely to have the listed contaminants occur in their drinking waters, considering the characteristics of

the listed contaminants, precipitation, PWS operation, and environmental conditions (soils, geology and land

use).

Pre-Screen Testing means sampling, testing, and reporting of the listed contaminants that may have newly

emerged as drinkingwater concerns and, in most cases, for which methods are in an early stage of development.

Pre-Screen Testing will be conducted by a limited number of PWSs (up to 200). Pre-Screen Testing will be

conducted for the UCMR (1999) List 3 contaminants. 

Random Sampling is a statistical sampling method by which each member of the population has an equal

probability of being selected as part of a sample (the sample being a small subset of the population which

represents the population as a whole).

Representative Sample (or National Representative Sample) means a small subset of all community and

non-transient non-community watersystemsserving10,000 or fewer people which EPA selects using a random

number generator. The PWSs in the representative sample are selected using a stratified random sampling

process that ensures that this small subset of PWSs will be representative of all small PWSs nationally.

Sampling means the act of collecting water from the appropriate location in a public water system (from the

applicable point from an intake or well to the end of a distribution line, or in some limited cases, a residential

tap) following proper methods for the particular contaminant or group of contaminants.
UCMR Reference Guide October 2001

B - 2

Sampling Point means a unique location where samples are to be collected. 

Screening Survey means sampling, testing, and reporting of the List 2 contaminants. These contaminants have

analyticalmethods which have been recently developed, and have uncertain potentialfor occurrence in drinking

water.

State means, each of the fifty States, the District of Columbia, U.S. Territories, and Tribal lands. For the

national representative sample, Guam, the Commonwealth of Puerto Rico, the Northern Mariana Islands, the

Virgin Islands, and American Samoa are each treated as an individual State. All Tribal water systems in the

U.S. that have status as a State under Section 1451 of the Safe Drinking Water Act for this program will be

considered collectively as one State for the purposes of selecting a representative sample of small PWSs. 

State Monitoring Plan (or State Plan) means a State's portion of the national representative sample of CWSs

and NTNCWSsserving10,000 or fewer people which must monitorfor unregulated contaminants(Assessment

Monitoring, Screening Survey(s) and Index Systems) and all large PWSs (PWSs serving greater than 10,000

people) which are required to monitor for Screening Survey contaminants. A State Plan will also include the

PWSs required to conduct Pre-Screen Testing, selected from the State’s designation of vulnerable PWSs.

Stratified Random Sampling is a procedure to draw a random sample from a population that has been divided

into subpopulations or strata, with each stratum comprised of a population subset sharing common

characteristics. Random samples are selected from each stratum proportional to that stratum’s proportion of

the entire population. The aggregate random sample (compiled from all the strata samples) provides a random

sample of the entire population that reflects the proportional distribution of characteristics of the population.

In the context of the UCMR, the population served by public water systems was stratified by size (with size

categories of 500 or fewer people served, 501 to 3,300 people served, and 3,301 to 10,000 people served) and

by water source type supplying the water system (ground water or surface water). This stratification was done

to ensure that PWSs randomly selected as nationally representative sample PWSs would proportionally reflect

the actual number of size and water type categories nationally.

Testing means, for the purposes of the UCMR and distinct from Pre-Screen Testing, the submission and/or

shipment of samples following appropriate preservation practices to protect the integrity of the sample; the

chemical, radiological, physical and/or microbiological analysis of samples; and the reporting of the sample’s

analytical results for evaluation. Testing is a subset of activities defined as monitoring.

Unregulated contaminants means chemical, microbiological, radiological and other substances that occur in

drinking water or sources of drinking water that are not currently regulated under the federal drinking water

program. EPA has not issued standards for these substances in drinking water (i.e., maximum contaminant

levels or treatment technology requirements).

Vulnerable time (or vulnerable period) means the time of the year determined as the most likely to have the

listed group of contaminants present at their highest concentrations or densities in drinking water.
UCMR Reference Guide October 2001

C - 1

Appendix C — Number of Small Systems in Representative Sample, by State

State/Tribe/Territory

Number of Small Systems Selected for Assessment Monitoring

Number of CWS Number of NTNCWS Total Number of

Systems

EPA Region 1

Connecticut 4 2 6

Maine 3 3 6

Massachusetts 11 1 12

New Hampshire 5 1 6

Rhode Island 2 0 2

Vermont 4 0 4

Region 1 Total 29 7 36

EPA Region 2

New Jersey 14 2 16

New York 22 7 29

Puerto Rico 8 1 9

Virgin Islands 1 1 2

Region 2 Total 45 11 56

EPA Region 3

Delaware 2 0 2

Maryland 6 2 8

Pennsylvania 26 11 37

Virginia 12 4 16

West Virginia 9 1 10

Region 3 Total 55 18 73

EPA Region 4

Alabama 15 0 15

Florida 28 4 32

Georgia 20 2 22

Kentucky 9 0 9

Mississippi 28 2 30

North Carolina 20 2 22

South Carolina 9 2 11
UCMR Reference Guide October 2001

State/Tribe/Territory

Number of Small Systems Selected for Assessment Monitoring

Number of CWS Number of NTNCWS Total Number of

Systems

C - 2

Tennessee 13 1 14

Region 4 Total 142 13 155

EPA Region 5

Illinois 27 1 28

Indiana 18 2 20

Michigan 20 4 24

Minnesota 14 2 16

Ohio 23 5 28

Wisconsin 19 2 21

Region 5 Total 121 16 137

EPA Region 6

Arkansas 13 0 13

Louisiana 26 1 27

New Mexico 6 2 8

Oklahoma 15 0 15

Texas 66 5 71

Region 6 Total 126 8 134

EPA Region 7

Iowa 16 0 16

Kansas 12 0 12

Missouri 18 2 20

Nebraska 7 1 8

Region 7 Total 53 3 56

EPA Region 8

Colorado 9 1 10

Montana 5 1 6

North Dakota 4 0 4

South Dakota 4 0 4

Utah 7 0 7

Wyoming 2 1 3
UCMR Reference Guide October 2001

State/Tribe/Territory

Number of Small Systems Selected for Assessment Monitoring

Number of CWS Number of NTNCWS Total Number of

Systems

C - 3

Region 8 Total 31 3 34

EPA Region 9

American Samoa 2 0 2

Arizona 12 0 12

California 43 5 48

Guam 1 0 1

Hawaii 3 0 3

Mariana Islands 2 0 2

Nevada 3 1 4

Region 9 Total 66 6 72

EPA Region 10

Alaska 4 0 4

Idaho 8 0 8

Oregon 9 2 11

Washington 15 2 17

Region 10 Total 36 4 40

Tribal Systems

Total for Tribes 6 1 7

National Total 710 90 800