Public Webinar: 

Revisions to the Unregulated Contaminant 

Monitoring Rule (UCMR 4) 

Meeting Presentations

Held January 13, 2016

USEPA, Office of Ground Water and Drinking Water 

Office of Water (MLK 140) EPA 815-R-16-001 January 2016
Revisions to the Unregulated 

Contaminant Monitoring Rule (UCMR 4) 

for Public Water Systems 

Public Webinar

January 13, 2016

Meeting starts at 1:00 p.m. E.T.

USEPA 

Office of Ground Water and Drinking Water

WELCOME

Gregory J. Carroll, USEPA

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 1 of 50
January 2016 U.S. Environmental Protection Agency 3

General Meeting Information

• Purpose

• Review of EPA’s proposed rule and discussion with the

public

• Webinar lines are muted to minimize background

noise

• 10 minute break at approximately 2:30 p.m.

• Public questions and discussion at the end of the

webinar

January 2016 U.S. Environmental Protection Agency 4

Agenda

1:00 Introduction (15 minutes)

1:15 Proposed UCMR 4 (30 minutes)

1:45 UCMR 4 Sampling Design (30 minutes)

2:15 UCMR 4 Reporting (15 minutes)

2:30 Break (10 minutes)

2:40 UCMR 4 Laboratory Approval Process & MRLs (20 minutes)

3:00 Submitting Public Comments (5 minutes)

3:05 Statements from Webinar Participants, Q&A

and Discussion 

(100 minutes)

4:45 Closing Remarks (5 minutes)

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 2 of 50
Introduction

Brenda Parris, USEPA

January 2016 U.S. Environmental Protection Agency 6

UCMR 4 Introduction Overview

• Regulatory background for UCMR

• Safe Drinking Water Act (SDWA) authority

• Relationship to:

• Candidate Contaminant List (CCL)

• Unregulated Contaminant Monitoring Rule (UCMR)

• Regulatory Determination

• Six-Year Review

• UCMR

• Objectives

• Approach

• Implementation

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 3 of 50
January 2016 U.S. Environmental Protection Agency 7

SDWA

• Passed in 1974, SDWA authorized EPA to set

enforceable health standards for contaminants in

drinking water

• National Primary Drinking Water Regulations (NPDWRs)

• 1996 SDWA amendments changed the process of

developing and reviewing NPDWRs

• CCL

• UCMR

• Regulatory Determination

• Six-Year Review

General Flow of SDWA Regulatory Processes

Opportunity for public comment

If yes

List unregulated 

contaminants*

Contaminant 

Candidate List

Review & decide 

whether to revise 

the standard

Six-Year Review

Develop or revise 

the drinking water 

standard*

Regulation 

Development

If yes

List and collect 

monitoring data for 

up to 30 unregulated 

contaminants 

Unregulated 

Contaminant 

Monitoring Rule

Determine whether 

at least five need a 

drinking water 

standard*

Regulatory 

Determinations

*For these three stages, we like to have increased specificity and confidence in the type of supporting data used

(e.g. health and occurrence). SDWA requires that we used best available data to make our decisions.

January 2016 U.S. Environmental Protection Agency 8

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January 2016 U.S. Environmental Protection Agency 9

CCL

• List of priority unregulated contaminants

• Chemicals and microbes

• Published every five years

• Known or anticipated to occur in public water systems

(PWSs)

• May require regulation under SDWA

January 2016 U.S. Environmental Protection Agency 10

Draft CCL 4

• Published February 4, 2015

• Carried forward the final list of CCL 3 contaminants

(multi-step process evaluating ~7,500 contaminants)

• Requested and evaluated contaminant nominations

from the public

• Evaluated any new data from previous negative

regulatory determinations

In establishing the proposed list of contaminants for UCMR 4, EPA started 

with this priority set of contaminants, which includes 100 chemicals or 

chemical groups and 12 microbes

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 5 of 50
January 2016 U.S. Environmental Protection Agency 11

UCMR

• SDWA section 1445(a)(2), as amended in 1996,

redesigned the UCMR Program; requirements

included:

•

•

•

•

•

Issue list of no more than 30 unregulated contaminants,

once every 5 years

Require PWSs serving population >10,000 people as well as

a nationally representative sample of PWSs serving ≤10,000

people to monitor

Store analytical results in the National Drinking Water

Contaminant Occurrence Database (NCOD)

Direct implementation – EPA manages program in

partnership with states

EPA funds testing/analytical costs for small PWSs

January 2016 U.S. Environmental Protection Agency 12

UCMR History

•

•

•

•

UCMR 1 (2001-2005, 26 contaminants)

UCMR 2 (2007-2011, 25 contaminants)

UCMR 3 (2012-2016, 30 contaminants)

• Monitoring concluded in 2015

• Data review will occur in 2016

UCMR 4 (2017-2021, 30 contaminants)

•

•

Proposed in the FR on December 11, 2015

Final publication anticipated in late 2016/early 2017

National occurrence data publically available: 

http://www.epa.gov/dwucmr/occurrence-data-unregulatedcontaminant-monitoring-rule

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January 2016 U.S. Environmental Protection Agency 13

Objective of UCMR Program

• Collect national occurrence data for suspected

drinking water contaminants that do not have

health-based standards set under the SDWA

• Drinking water occurrence information is used to

support future regulatory actions to protect public

health

• Public will benefit from information about whether or

not unregulated contaminants are present in their

drinking water

January 2016 U.S. Environmental Protection Agency 14

UCMR Approach

• UCMR established a 3-tiered approach for monitoring

• Assessment Monitoring (List 1)

• Screening Survey (List 2)

• Pre-Screen Testing (List 3)

• Based on:

• Availability and complexity of analytical methods

• Laboratory capacity

• Sampling frequency

• Relevant universe of PWSs

• Other considerations (e.g., cost/burden)

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 7 of 50
January 2016 U.S. Environmental Protection Agency 15

Typical UCMR System Applicability

System Type Systems Serving

> 10,000

Systems Serving 

≤ 10,000

Assessment Monitoring 

(List 1 Contaminants) CWS1 & NTNCWS2 All systems (~4,200) 800 randomly selected 

systems

Screening Survey 

(List 2 Contaminants) CWS & NTNCWS

All systems (~410) serving 

more than 100,000, and 

~320 randomly selected 

systems serving 10,001 to 

100,000

480 randomly selected 

systems

Pre-Screen Testing 

(List 3 Contaminants) May be conducted by a limited number of PWSs

1Community Water System

2Non-transient Non-community Water System

January 2016 U.S. Environmental Protection Agency 16

EPA Implementation Roles

• Review, track and determine PWS applicability and

monitoring progress

• Coordinate Laboratory Approval Program

• Provide technical support for Regions, states,

PWSs and laboratories

• Coordinate outreach

• Assist and support Regional compliance efforts

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 8 of 50
January 2016 U.S. Environmental Protection Agency 17

EPA Implementation Roles

• Small PWS support:

• EPA funds small system testing including kits, sample

analysis and shipping

• Manages sample kit distribution

• Maintains lab and implementation contracts to support

UCMR

• Responsible for data review

• Large and small PWS support:

• Safe Drinking Water Accession and Review System (SDWARS)

reporting system and users

• Prepares data for NCOD

January 2016 U.S. Environmental Protection Agency 18

States’ Role in the UCMR 4 Program

• State participation is voluntary

• EPA has established Partnership Agreements (PAs)

under previous UCMRs and will continue to do so for

UCMR 4

• States, tribes and territories help EPA implement the UCMR

program; help to ensure high data quality

• Review and revise State Monitoring Plans (SMPs)

• Update system information to preload into SDWARS

• Review and approve proposed Ground Water Representative

Monitoring Plans (GWRMPs)

• Compliance assistance

• Notification and instructions for systems

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Regulatory Determination

• Determine which contaminants may have an adverse

effect on human health

• Determine if a contaminant occurs in drinking water at

a frequency and at levels of public health concern

• Meaningful opportunity for health risk reduction

• Made every five years

• Determinations for at least five contaminants from the

CCL

• UCMR helps provide the necessary data

January 2016 U.S. Environmental Protection Agency 20

Six-Year Review

• Reviews existing NPDWRs and determines if a

revision is appropriate

• Includes the re-evaluation of exposure to regulated

contaminants based on their health effects and

occurrence in drinking water

• Any revisions to existing NPDWRs must maintain

protection or provide for greater health protection

• Made every six years

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Proposed UCMR 4 

Melissa Simic, USEPA

January 2016 U.S. Environmental Protection Agency 22

Proposed UCMR 4 - Overview

• Timeline

• Notable proposed changes from UCMR 3

• Contaminant selection process

• Proposed contaminants and analytical methods

• Estimated costs

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UCMR 4 Timeline

2013 - 2014 2015 2016 2017 2018 - 2020 2021

UCMR 4 Stakeholder Meeting

January 13, 2016

May 15, 2013

June 25, 2014

UCMR 4 

Stakeholder 

Meetings

UCMR 4 Development

Review Rule Drafting

Complete 

Reporting/ 

Analysis of 

Data

Late 2016/ Early 2017

UCMR 4 Final Rule

Published

December 11, 2015

UCMR 4 Proposal 

Published

Public Comment 

Period Ends

February 9, 2016

UCMR 4 

Pre-implementation Monitoring

Activities

Public Comment 

Period Begins

December 31, 2015

Applicability Date

Laboratory Approval 

Process GWRMP Submittals 

January 2016 U.S. Environmental Protection Agency 23

January 2016 U.S. Environmental Protection Agency 24

Notable Proposed Changes

• Analytes

• Applicability

• Monitoring time frame

• Sampling frequency

• Sampling locations

• Reporting requirements

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January 2016 U.S. Environmental Protection Agency 25

UCMR 4 Candidate Contaminants –

Information Compendium

• Provides the initial list of contaminants that EPA

considered

• Outlines the contaminant prioritization process

• Indicates the reason a contaminant was not

included on the proposed list

• Provides supporting information for each of the

proposed contaminants

January 2016 U.S. Environmental Protection Agency 26

UCMR 4 Candidate Contaminants –

Information Compendium

• Primary source for the information is the CCL program

• Reviewed and evaluated other publically available data

sources

• Generally includes five sections:

• Background & Use

• Health Effects

• Production & Release

• Occurrence in Water

• Persistence & Mobility

• The document is located in the docket

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 13 of 50
UCMR 4 Prioritization Process

45 CCL + 48 related non-CCL analytes1

[16 methods] 

UCMR 4 Candidates:

31 CCL + 18 related non-CCL 

analytes [9 methods] 

+ other contaminants under 

consideration2

Propose up to 30 

contaminants for 

comment

• Not monitored for on UCMR 2 or UCMR 3

• Anticipated to have national occurrence

• Have a completed & validated drinking water

method

Most contaminants in method group:

• Have an available health assessment to facilitate

regulatory determinations and/or high public concern 

• Have critical health endpoints (e.g., likely and

suggestive carcinogens), active-use pesticides

• Have an occurrence data gap

• Workgroup and stakeholder input

• Cost-effective method group

• Further evaluation of health and occurrence data

• Implementation factors (e.g., laboratory capacity)

After considering comments, publish up to 

30 contaminants for UCMR 4 monitoring 

tentatively starting in 2018

1 Analytes with potential health effects of concern that can be measured concurrently, 

using the analytical methods for the CCL contaminants; creates a more cost-effective 

design and reduces the likelihood of needing to include them in a subsequent UCMR.

2 Workgroup or stakeholder nominations

[100 chemicals or chemical groups + 

12 microbes] 

Draft Contaminant Candidate List (CCL) 4

27

Proposed UCMR 4 Analytes

ADDA ELISA

“total microcystins”

EPA Method 544 (SPE LC/MS/MS)

microcystin-LA microcystin-RR

microcystin-LF microcystin-YR

microcystin-LR nodularin

microcystin-LY

EPA Method 545 (LC/ECI-MS/MS)

anatoxin-a cylindrospermopsin

EPA Method 200.8 (ICP-MS) or alternate SM or ASTM

germanium manganese

EPA Method 525.3 (SPE GC/MS)

alpha-hexachlorocyclohexane profenofos

chlorpyrifos tebuconazole

dimethipin total permethrin (cis- & trans-)

ethoprop tribufos

oxyfluorfen

EPA Method 552.3 (GC/ECD) or 557 (IC/ECI-MS/MS)

HAA5 (regulated) HAA9

HAA6Br

EPA Method 541 (GC/MS)

1-butanol 2-propen-1-ol

2-methoxyethanol

EPA Method 530 (GC/MS)

butylated hydroxyanisole quinolone

o-toluidine

EPA invites public comment on the following 

contaminants that were considered by the 

workgroup but not included in the proposed list: 

Legionella pneumophila and Mycobacterium 

avium, ammonia, and the pesticides 

vinclozolin, hexazinone and disulfoton.

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 14 of 50
January 2016 U.S. Environmental Protection Agency 29

Cyanotoxins

EPA Method 544 (LC/MS/MS1)

Analyte

EPA Health 

Advisory (HA)

Critical Health 

Effect

Occurrence

microcystin-LR

1.6 μg/L (ten-day HA for 

school-age children and 

adults); 

0.3 μg/L (ten-day HA for 

bottle-fed infants and 

young children)

Liver effects

Microcystins in water 

supplies: 77 samples from 

33 water supplies; Range of 

detects = <0.15 - 0.36 μg/L 

(Haddix et al., 2007)

microcystin-LA

microcystin-LF

microcystin-LY

microcystin-RR

microcystin-YR

nodularin Not available Liver toxicity Not available

1Liquid Chromatography/Tandem Mass Spectrometry

2Total microcystins will also be measured by ADDA ELISA; EPA HA applies

2

January 2016 U.S. Environmental Protection Agency 30

Cyanotoxins

EPA Method 545 (LC/ESI-MS/MS1)

Analyte

EPA Health 

Advisory (HA)

Critical Health 

Effect

Occurrence

anatoxin-a Not available Targets nervous system Florida Waters (Burns

2008), drinking water 

max = 8.46 μg/L

cylindrospermopsin 3 μg/L (ten-day HA for 

school-age children 

through adults);

0.7 μg/L (ten-day HA for 

bottle-fed infants and 

young children)

Increased relative 

kidney weight and 

decreased urinary 

protein

Florida Waters (Burns 

2008), drinking water 

range of detects = 8-97 

μg/L

1Liquid Chromatography Electrospray Ionization-Tandem Mass Spectrometry

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 15 of 50
January 2016 U.S. Environmental Protection Agency 31

Metals

EPA Method 200.81(ICP-MS2)

Analyte

Health Reference 

Level (HRL)

Critical Health 

Effect

Occurrence

germanium 7.44 μg/L3 Kidney, ureter, bladderchanges in tubules NIRS

4 drinking water 

range of detects = 26-230

μg/L; detected in 4 out of 

989 samples

manganese 300 μg/L Central nervous system 

effects 

NIRS drinking water 

median = 11.96 μg/L; 

detected in 672 out of 

989 samples

1Metals can also be measured by alternate Standard Methods (SM) 3125 or SM 3125-09 or ASTM International D5673-10 

2

Inductively Coupled Plasma-Mass Spectrometry

3Based on OW’s evaluation of the dose information in the critical study, the HRL should be about ten times larger (i.e., 

0.744 to 7.44 μg/L)

4National Inorganics and Radionuclides Survey, 1984-1986

January 2016 U.S. Environmental Protection Agency 32

Pesticides

EPA Method 525.3 (SPE GC/MS1)

Analyte

Health Reference 

Level (HRL) Critical Health Effect Occurrence

alphahexachlorocyclohexane0.006 μg/L Cancer NAWQA2 ambient water 

median = 0.011 μg/L; 

detected in 21 out of 7,119 

samples 

chlorpyrifos Not available Significant plasma and RBC 

cholinesterase inhibition

PDP3 drinking water = not

detected in the 13 sites 

sampled

dimethipin 153 μg/L Kidney, lungs, duodenum, 

liver, glandular stomach, 

heart, aortic artery, and 

testes toxicity; decreased 

body weight gain

TRI4 = 87 pounds released in 1 

state in 2010

1Solid Phase Extraction and Capillary Column Gas Chromatography-Mass Spectrometry

2USGS, National Water-Quality Assessment Program (NAWQA)

3Pesticide Data Program (PDP)

4Toxic Release Inventory (TRI)

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 16 of 50
January 2016 U.S. Environmental Protection Agency 33

Pesticides

EPA Method 525.3 (SPE GC/MS)

Analyte

Health Reference 

Level (HRL) Critical Health Effect Occurrence

ethoprop 1.25 μg/L Cancer PDP drinking water = not

detected in the 13 sites 

sampled

oxyfluorfen 210 μg/L5 Liver toxicity PDP drinking water = not

detected in the 13 sites 

sampled

profenofos 0.35 μg/L Plasma and RBC 

cholinesterase (ChE) 

inhibition

PDP drinking water = not

detected in the 13 sites 

sampled

5Human Health Benchmark for Pesticides

January 2016 U.S. Environmental Protection Agency 34

Pesticides

EPA Method 525.3 (SPE GC/MS)

Analyte

Health Reference 

Level (HRL) Critical Health Effect Occurrence

tebuconazole 210 μg/L Decreased body weights, 

absolute brain weights, brain 

measurements and motor 

activity in offspring

PDP drinking water median 

detect = 0.01 μg/L; detected 

at 4 out of 13 sites

total permethrin (cis- & 

trans-)

3.65 μg/L Cancer California Drinking Water 

Monitoring Data = not 

detected in the 35 PWSs 

sampled

tribufos 7 μg/L Plasma cholinesterase (ChE) 

inhibition

PDP drinking water = not

detected in the 13 sites 

sampled

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 17 of 50
Haloacetic Acids (HAAs)

EPA Method 552.3 (GC-ECD)

1 or EPA Method 557 (IC-ESI-MS/MS)2

Analyte MCLG3 Health Effects

Occurrence4

(Median conc. and # 

detections)

HAA6Br 

Group

HAA5

Group

HAA9

Group

bromochloroacetic acid

(BCAA)

Not

available

Clear evidence of carcinogenicity

(NTP 2009); Reproductive effects

3.3 μg/L; 

263 of 291 systems

HAA6Br

HAA9

bromodichloroacetic 

acid (BDCAA)

Not

available

Clear evidence of carcinogenicity

(NTP 2014)

3.2 μg/L; 

90 of 102 systems

chlorodibromoacetic 

acid (CDBAA)

Not

available

3.2 μg/L; 

66 of 101 systems

tribromoacetic acid

(TBAA)

Not

available

5 μg/L; 

15 of 98 systems

monobromoacetic acid

(MBAA)

Not

available

1.5 μg/L; 

124 of 291 systems

HAA5

Group 

MCL5 = 

60 μg/L

dibromoacetic acid

(DBAA)

Not

available

Clear evidence of carcinogenicity in 

mice (NTP 2007)

2.3 μg/L; 

202 of 291 systems

dichloroacetic acid

(DCAA) 0 μg/L Cancer

11 μg/L; 

272 of 291 systems

monochloroacetic acid

(MCAA) 70 μg/L Decreased body, liver, kidney and 

spleen weights

3 μg/L; 

215 of 290 systems

trichloroacetic acid

(TCAA) 20 μg/L Liver changes

9.7 μg/L; 

259 of 291 systems

1Gas Chromatography with Electron Capture Detection

2

Ion Chromatography Electrospray Ionization Tandem Mass Spectrometry 

3MCLGs established under the Stage 1 and Stage 2 DBPRs

4Disinfection By-product Information Collection Rule (DBP ICR) (1997-1998)

5The HAA5 group is currently regulated in drinking water at a MCL of 60 μg/L per Stage 1 and Stage 2 DBPRs 35

January 2016 U.S. Environmental Protection Agency 36

Alcohols

EPA Method 541 (GC/MS1)

Analyte

Health Reference 

Level (HRL)

Critical Health 

Effect

Usage

1-butanol 700 μg/L Abnormally diminished 

activity in the 

body/organs; inability to 

control muscles

TRI2 = 11,093,815 pounds 

released in 47 states in 

2010

2-propen-1-ol 35 μg/L Impaired kidney 

function and increased 

relative liver, spleen and 

kidney weights

TRI = 445,833 pounds 

released in 13 states in 

2010

2-methoxyethanol 21 μg/L Reproductive effects TRI = 23,240 pounds 

released in 16 states in 

2010

1Gas Chromatography-Mass Spectrometry

2Toxic Release Inventory (TRI)

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 18 of 50
January 2016 U.S. Environmental Protection Agency 37

Semivolatile Organic Chemicals

EPA Method 530 (GC/MS)

Analyte

Health Reference 

Level (HRL)

Critical Health 

Effect

Usage

butylated

hydroxyanisole

0.581 μg/L Changes in liver weight NREC

2 Median = 0.1 

μg/L; detected at 2 out 

of 85 sites

o-toluidine 0.194 μg/L Cancer TRI3 = 6,623 pounds 

released in 1 state in 

2010

quinoline 0.01 μg/L Cancer TRI = 15,789 pounds 

released in 9 states in 

2010

1Gas Chromatography-Mass Spectrometry

2USGS, National Reconnaissance of Emerging Contaminants (NREC) Surface Water Data, 1999-2004

3Toxic Release Inventory (TRI)

January 2016 U.S. Environmental Protection Agency 38

Additional Contaminants and Indicators 

Considered for UCMR 4

• Legionella pneumophila (on CCL 4)

• Method was not ready at the time of proposal

• Thought to be largely a premise plumbing issue

• Health effects:

• Legionnaire’s Disease and Pontiac Fever

• 52 reported waterborne disease outbreaks affecting

225 people between 1990 and 2010 (CDC MMWR)

• OW Draft (October 2015) - Technologies for Legionella

Control: Scientific Literature Review:

• http://www.epa.gov/sites/production/files/2015-

10/documents/drafttechlegionellaoct2015.pdf

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 19 of 50
January 2016 U.S. Environmental Protection Agency 39

Additional Contaminants and Indicators 

Considered for UCMR 4

• Mycobacterium avium (on CCL 4)

• Method was not ready at the time of proposal

• Health effects:

• Pulmonary disease, lymphadenitis, post-traumatic wound

infection

• No reported outbreaks between 1990 and 2008 (CDC

MMWR)

January 2016 U.S. Environmental Protection Agency 40

Additional Contaminants and Indicators 

Considered for UCMR 4

• Ammonia

• May be oxidized to nitrite and nitrate (contaminants of

greater toxicological concern) via nitrification

• Nitrite/Nitrate are regulated in drinking water: MCLG/MCL 1,000

and 10,000 μg/L respectively based on methemoglobinemia

• The NPDWR for nitrite and nitrate requires compliance

monitoring at each entry point to the distribution system

(EPTDS)

• Limited research indicates that nitrification downstream of EPTDS

(i.e., in distribution system) may lead to higher nitrite and/or

nitrate exposure (especially for PWSs using chloramine

disinfection)

• Measuring ammonia at entry point could serve as a surrogate for

nitrification potential

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 20 of 50
January 2016 U.S. Environmental Protection Agency 41

Additional Contaminants and Indicators 

Considered for UCMR 4

• Three pesticides in method 525.3 were identified as

lower priority based on data evaluation:

• Disulfoton: Production cancelled 2009; non-cancer

endpoint; not detected in 2,300 samples from 295 systems

(UCMR 1 SS 2001-2003); not persistent to moderately

persistent in the environment; very regionalized usage

• Hexazinone: Not on CCL 4; non-cancer endpoint; not

detected in 221 samples (PMP, 1999); moderately persistent

to persistent in the environment

• Vinclozolin: No current usage; non-cancer endpoint; was

being phased out in 2004; persistent in the environment

January 2016 U.S. Environmental Protection Agency 42

Proposed Contaminants

• EPA invites comments on:

• The proposed contaminants and their

associated methods

• The six additional contaminants

considered for UCMR 4, but not

included on the proposed list

• Additional contaminants that may not

have been considered for UCMR 4

• Suggestions for which

contaminant(s) to remove if others

are added

• Additional consensus analytical

methods for the proposed

contaminants

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 21 of 50
January 2016 U.S. Environmental Protection Agency 43

UCMR 4 Cost Estimates

Average Annual Cost per Respondent (2017-2021)

Labor Non-labor

(methods & shipping)

Labor plus 

Non-labor

Small systems $100 $0 $100

Large systems $410 $3,630 $4,040

Very large systems $750 $9,780 $10,530

States $8,990 $0 $8,990

EPA $815,240 $3,864,860 $4,680,100

January 2016 U.S. Environmental Protection Agency 44

UCMR 4 Cost Estimates

Respondent Avg. Annual Cost All Respondents 

(2017-2021) 

Small systems (25-10,000), including labor only (non-labor 

costs paid for by EPA)

$0.16 m

Large systems (10,001-100,000), including labor and non-labor 

costs

$15.7 m

Very large systems (100,001 and greater), including labor and 

non-labor costs

$4.3 m

States, including labor costs related to implementation 

coordination

$0.50 m

EPA, including labor for implementation, non-labor for small 

system testing

$4.7 m

AVERAGE ANNUAL NATIONAL TOTAL $25.3 m

*Note that totals may not equal the sum of components due to rounding.

*EPA assumes that one-third of the systems would monitor during each of the three monitoring years.

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 22 of 50
UCMR 4 Sampling Design

Brenda Parris, USEPA

January 2016 U.S. Environmental Protection Agency 46

UCMR 4 Sampling Design Overview

• System applicability

• Sampling frequency and timing

• Revised sampling locations

• Phased sample-analysis for microcystins

• Haloacetic acid (HAA) groups

• Source water sampling

• Representative sampling

• Schedules

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 23 of 50
System Applicability: 

National Sample Assessment Monitoring Design (List 1)

System Size

(# of people 

served)

10 Cyanotoxins 20 Additional Chemicals

Total # of 

Systems per 

Size Category

Small systems1

(25 – 10,000)

800 randomly selected SW or 

GWUDI systems

800 randomly selected SW, 

GWUDI and GW systems

1,600

Large systems2

(10,001 and over)

All SW or GWUDI systems 

(1,987)

All SW, GWUDI and GW 

systems (4,292) 4,292

TOTAL 2,787 5,092 5,892

1 Total for small systems is additive because these systems would only be selected for one component of UCMR 4 

sampling (10 cyanotoxins or 20 additional chemicals). EPA would pay for all analytical costs associated with 

monitoring at small systems.

2 Large system counts are approximate. The number of large systems is not additive. All SW and GWUDI systems 

would monitor for cyanotoxins; those same systems would also monitor for the 20 additional List 1 chemicals, as 

would the large GW systems.

January 2016 U.S. Environmental Protection Agency 47

January 2016 U.S. Environmental Protection Agency 48

Sampling Frequency and Timing

• Sample collection time frame

• March through November

• Exclude December, January and February

• Except for re-sampling events, as needed

• Better reflect the times of year when

contaminants are more likely to occur in drinking

water (e.g., cyanotoxins and pesticides)

• Monitoring will take place over a three-year period

(2018-2020)

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 24 of 50
Sampling Frequency and Timing

Contaminant 

Type

Water Source 

Type

Time Frame Frequency

List 1 

Contaminants -

Cyanotoxins

SWor GWUDI March – November You must monitor twice a month for four 

consecutive months (total of eight sampling 

events). Sample events must occur two weeks 

apart.

List 1 

Contaminants –

Additional 

Chemicals 

SW or GWUDI March – November You must monitor four times during your 12-

month monitoring period. Sample events must 

occur two months apart. (Example: If your first 

sampling event is in March, the second 

monitoring must occur during May, the third 

during July, and the fourth during September). 

GW March – November You must monitor two times during your 12-

month monitoring period. Sample events must 

occur six months apart. (Example: If your first 

monitoring is in March, the second monitoring 

must occur during September. If your first 

monitoring is in November, the second 

monitoring must occur in May).

January 2016 U.S. Environmental Protection Agency 49

January 2016 U.S. Environmental Protection Agency 50

Sampling Locations - Overview

• Microcystins

• Phased sample analysis

• PWSs will collect all required samples but not all samples may need to be

analyzed

• “Total microcystins” (ADDA ELISA) at source water intake and EPTDS

• Method 544 (specific microcystin congeners) at the EPTDS

• Temperature and pH at source water intake (concurrently)

• Haloacetic Acid Groups

• Stage 2 Disinfection Byproduct Rule (DBPR) locations and/or

distribution system maximum residence time (DSMRT)

• Source water intake [bromide and total organic carbon (TOC)]

concurrently

• Remaining UCMR 4 contaminants

• EPTDS sampling

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 25 of 50
Phased Sample-Analysis for Microcystins

ELISA analysis of the EPTDS 

sample would be the first 

step for consecutive 

systems (purchase 100% of 

their water)

0.3 μg/L (the reporting limit 

for total microcystins)

PWSs (SW and GWUDI) must 

collect all required samples for 

each sampling event (source 

water intake and EPTDS 

samples) but all samples may 

not need to be analyzed.

ELISA result <0.3 μg/L ELISA result ≥0.3 μg/L 

Source water intake samples 

analyzed for total microcystins 

by ADDA ELISA (PWS will also 

take pH and temperature 

measurements)

Source water result would be 

reported to EPA. Other collected 

samples (for ELISA and 544) 

from the EPTDS would not be 

analyzed for that sampling event

Source water result would be 

reported to EPA. The EPTDS 

sample would then be 

analyzed by ELISA

EPTDS ELISA result 

<0.3 μg/L 

EPTDS result would be reported 

to EPA and the 544 sample 

would not be analyzed for this 

particular sampling event

EPTDS ELISA result 

≥0.3 μg/L 

EPTDS result would be reported 

to EPA and the other microcystin 

sample collected at the EPTDS 

would be analyzed using Method 

544 to identify particular 

microcystin congeners

*Method 544 (identifies six specific congeners) is not a confirmation check of the ADDA ELISA result (provides a ‘total’ of 80-100 congeners)

Sampling Location Samples Collected

Source water intake ADDA ELISA, pH and 

temperature

Entry point to the 

distribution system 

(EPTDS)

ADDA ELISA, EPA 

Method 544 and 545

January 2016 U.S. Environmental Protection Agency 52

Sampling Locations – HAA Groups

• If subject to Stage 2 DBPR:

• Collect distribution system samples at the locations

identified under that rule

• If not subject to Stage 2 DBPR:

• Collect samples at a location that represents the

DSMRT

• DSMRT is an active point (i.e., location that currently provides

water to customers) in the distribution system where water

has been in the system longest relative to the EPTDS

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 26 of 50
January 2016 U.S. Environmental Protection Agency 53

Sampling Locations – HAA Groups

• UCMR 4 HAA samples and HAA5

Stage 2 DBPR compliance samples

can be collected at the same time

• Must use a UCMR 4 approved

laboratory and EPA Method 552.3

or 557

• PWSs report HAA results to EPA for

three groups (HAA5, HAA6Br and

HAA9)

• Labs also report individual HAA 

analyte data for QC purposes

• Better understand co-occurrence

between regulated and unregulated

disinfection byproducts

HAA Groups

dichloroacetic acid (DCAA)

HAA5

HAA9

monochloroacetic acid (MCAA)

trichloroacetic acid (TCAA)

monobromoacetic acid (MBAA)

HAA6Br

dibromoacetic acid (DBAA)

bromochloroacetic acid (BCAA)

bromodichloroacetic acid (BDCAA)

chlorodibromoacetic acid (CDBAA)

tribromoacetic acid (TBAA)

January 2016 U.S. Environmental Protection Agency 54

Source Water Sampling

• Applies to microcystin (i.e., ADDA ELISA, pH and temperature)

and HAA (i.e., bromide and TOC) monitoring

• Untreated water entering the water treatment plant

• A location prior to any treatment

• Systems subject to:

• The Long Term 2 Enhanced Surface Water Treatment Rule (LT2ESWTR)

• Use the source water sampling site(s) under that rule 

• Stage 1 DBPR (remain unchanged under Stage 2 DBPR)

• Use TOC source water sampling site(s)

• Systems with two different source water sampling locations for

LT2/Stage 1 DBPR

• Use sample point that best represents the definition of source water

sample location(s) for UCMR

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 27 of 50
January 2016 U.S. Environmental Protection Agency 55

Representative Sampling

• Large GW systems with multiple EPTDSs can

sample at representative sampling locations rather

than at each EPTDS if prior approval is received

• Representative sampling plans approved under prior

UCMRs will be recognized for UCMR 4

• These systems must submit a copy of the

documentation from their state or EPA that approved

their representative sampling locations

January 2016 U.S. Environmental Protection Agency 56

Representative Sampling

• New GW representative monitoring plans must be

submitted for review by the state or EPA within

120 days from publication of the final rule

• Approved representative locations must be loaded

into the SDWARS by December 31, 2017

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 28 of 50
January 2016 U.S. Environmental Protection Agency 57

Schedules

• Large system schedules

• EPA initially drafts schedule

• Partnered state has opportunity to review and modify

• PWS has opportunity to review and modify

• Systems must NOT modify their schedules to avoid a

suspected vulnerable period

• Small system schedules

• EPA initially drafts schedule

• Partnered state has opportunity to review and modify

January 2016 U.S. Environmental Protection Agency 58

Sampling Design

• EPA invites comment on:

• Monitoring time frame (MarchNovember)

• Cyanotoxin monitoring

approach

• Including “indicator” monitoring

• Phased sample-analysis for

microcystins

• Balance between burden

(e.g., number of PWSs,

monitoring frequency) and

data representativeness

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 29 of 50
UCMR 4 Reporting

Jennifer Tully, ORISE

January 2016 U.S. Environmental Protection Agency 60

UCMR 4 Reporting Overview

• Initial and on-going reporting requirements

• New/revised data elements

• Timing of reporting

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 30 of 50
January 2016 U.S. Environmental Protection Agency 61

Reporting by All Systems §141.35(b) 

• EPA’s electronic data reporting system (SDWARS)

can be accessed:

• http://www.epa.gov/dwucmr

• Hard copy documentation mailed:

• UCMR Sampling Coordinator, USEPA, Technical Support

Center, 26 West Martin Luther King Drive (MS 140),

Cincinnati, OH 45268

• Electronic files emailed:

• UCMR_Sampling_Coordinator@epa.gov

January 2016 U.S. Environmental Protection Agency 62

Large System Reporting §141.35(c)

• Contact and zip code information

• SDWARS by December 31, 2017

• Sampling location information

• SDWARS by December 31, 2017

• Changes after applicability date must be submitted to (with

reason) and approved by EPA’s UCMR Sampling Coordinator

• Samples

• PWSs must report all data elements specified in §141.35(e) Table 1

(e.g., disinfectant type, treatment information and disinfectant

residual)

• Monitoring results

• Entered by UCMR approved laboratory to SDWARS

• Reviewed and submitted by PWS

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 31 of 50
January 2016 U.S. Environmental Protection Agency 63

Small System Reporting §141.35(d)

• If notified that system will be subject to UCMR 4:

• Contact and zip code information

• To SDWARS within 90 days of notification (new)

• Sampling location information

• To SDWARS by December 31, 2017 (new)

• Samples

• PWSs must report all data elements specified in §141.35(e) Table

1 on each sample form as appropriate (e.g., disinfectant type,

treatment information and disinfectant residual)

• Monitoring results

• Entered by contracted laboratory to SDWARS

• Reviewed by EPA

• Viewed by PWS

Reporting Data Elements §141.35(e) 

1. Public Water System Identification (PWSID) 

Code 14. Sample Identification Code

2. Public Water System Name* 15. Contaminant

3. Public Water System Facility Identification 

Code 16. Analytical Method Code 

4. Public Water System Facility Name* 17. Extraction Batch Identification Code

5. Public Water System Facility Type* 18. Extraction Date

6. Water Source Type 19. Analysis Batch Identification Code

7. Sampling Point Identification Code 20. Analysis Date

8. Sampling Point Name* 21. Sample Analysis Type (more details)

9. Sampling Point Type Code 22. Analytical Results—Sign

10. Disinfectant Type (more details) 23. Analytical Result—Measured Value

11. Treatment Information (more details) 24. Additional Value

12. Disinfectant Residual Type 25. Laboratory Identification Code

13. Sample Collection Date 26. Sample Event Code

Blue indicates new data element Green indicates updated data element

*New data elements that were used in previous UCMRs but not required per rule language

January 2016 U.S. Environmental Protection Agency 64

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 32 of 50
January 2016 U.S. Environmental Protection Agency 65

Disinfectant Type - Data Element 10 

• PEMB = permanganate (applied before 

SR sample location)

• PEMA = permanganate (applied after SR 

sample location)

• HPXB = hydrogen peroxide (applied 

before SR sample location)

• HPXA = hydrogen peroxide (applied after 

SR sample location)

• CLGA = gaseous chlorine

• CLOF = offsite generated hypochlorite 

(stored as a liquid form) 

• CLON = onsite generated hypochlorite

• CAGC = chloramine (formed from

gaseous chlorine)

• CAOF = chloramine (formed from offsite 

hypochlorite)

• CAON = chloramine (formed from onsite 

hypochlorite)

• CLDB = chlorine dioxide (applied before 

SR sample location)

• CLDA = chlorine dioxide (applied after SR 

sample location)

• OZON = ozone

• ULVL = ultraviolet light

• OTHD = all other types of 

disinfectant/oxidant

• NODU = no disinfectant/oxidant used

January 2016 U.S. Environmental Protection Agency 66

Treatment Information - Data Element 11 

• CON = conventional (non-softening)

• SCO = softening conventional

• RBF = river bank filtration

• PSD = pre-sedimentation

• INF = in-line filtration

• DFL = direct filtration

• PCF = precoat filtration

• SSF = slow sand filtration

• BIO = biological filtration

• REC = reactor clarification (e.g., solids contact 

clarification, slurry recirculation clarification, Aciflo®)

• SBC = sludge blanket clarification (e.g., Pulsator®,

Super Pulsator®, contact adsorption clarifiers,

floc-blanket clarifiers)

• ADC = adsorption clarification (contact adsorption 

clarification)

• UTR = unfiltered treatment

• PAC = application of powder activated carbon

• GAC = granular activated carbon (not part of 

filters in CON, SCO, INF, DFL or SSF)

• AIR = air stripping (packed towers, diffused 

gas contactors)

• POB = pre-oxidation/disinfection with 

chlorine (applied before SR sample 

location)

• POA = pre-oxidation/disinfection with 

chlorine (applied after SR sample location)

• MFL = membrane filtration

• IEX = ionic exchange

• UVT = ultraviolet light

• AOX = advanced oxidation (ultraviolet light 

with hydrogen peroxide and/or ozone)

• DAF = dissolved air floatation

• CWL = clear well/finished water storage 

without aeration

• CWA = clear well/finished water storage 

with aeration

• ADS = aeration in distribution system 

(localized treatment)

• OTH = all other types of treatment

• NTU = no treatment used

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 33 of 50
January 2016 U.S. Environmental Protection Agency 67

Sample Analysis Type - Data Element 21 

• CF = concentration fortified; the concentration of 

a known contaminant added to a field sample 

reported with sample analysis types LFSM, 

LFSMD, LFB, CCC and QCS.

• CCC = continuing calibration check; a calibration 

standard containing the contaminant, the 

internal standard, and surrogate analyzed to 

verify the existing calibration for those 

contaminants.

• FS = field sample; sample collected and 

submitted for analysis under this rule.

• IS = internal standard; a standard that measures 

the relative response of contaminants.

• LFB = laboratory fortified blank; an aliquot of 

reagent water fortified with known quantities of 

the contaminants and all preservation 

compounds.

• LRB = laboratory reagent blank; an aliquot of reagent 

water treated exactly as a field sample, including the 

addition of preservatives, internal standards, and 

surrogates to determine if interferences are present in 

the laboratory, reagents, or other equipment.

• LFSM = laboratory fortified sample matrix; a UCMR 

field sample with a known amount of the contaminant 

of interest and all preservation compounds added.

• LFSMD = laboratory fortified sample matrix duplicate; 

duplicate of the laboratory fortified sample matrix.

• QCS = quality control sample; a sample prepared with 

a source external to the one used for initial calibration 

and CCC. The QCS is used to check calibration standard 

integrity.

• QH = quality HAA; HAA sample collected and 

submitted for quality control purposes.

• SUR = surrogate standard; a standard that assesses 

method performance for each extraction.

January 2016 U.S. Environmental Protection Agency 68

Timing of Reporting Results

• Large systems

• Laboratory posts results to SDWARS within 120 days of

sample collection

• Systems review, approve and submit to state and EPA

within 60 days of laboratory’s post

• Small systems

• EPA will still manage laboratory contracts for small

water systems

• Laboratory posts results to SDWARS within 120 days of

sample collection

• Systems have the option to view data in SDWARS

• EPA will not mail hard copy reports to systems or states

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 34 of 50
10-Minute Break

UCMR 4 Laboratory Approval 

Process and MRLs

Melissa Simic, USEPA

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 35 of 50
January 2016 U.S. Environmental Protection Agency 71

UCMR 4 Laboratory Approval Program 

• Similar to the process used in UCMR 3

• Only UCMR 4 approved laboratories can analyze UCMR

4 samples collected at PWSs

• Approval is by method and by individual location

• A laboratory may apply for any number of UCMR 4 methods

• Laboratories need to meet:

• UCMR 4 approval program criteria

• Required equipment criteria

• Laboratory performance criteria

• Data reporting criteria

January 2016 U.S. Environmental Protection Agency 72

UCMR 4 Laboratory Approval Manual

• Procedures for obtaining UCMR 4 approval and procedures for revocation

of approval

• Quality assurance (QA) and quality management requirements

• Initial Demonstration of Capability (IDC)

• Minimum reporting level (MRL) verification

• Quality control (QC) requirements:

• Extraction/Analysis Batch

• Initial calibration of analytical instruments

• Continuing calibration checks (CCC)

• Surrogate and internal standard 

• Laboratory reagent blanks (LRB) and laboratory fortified blanks (LFB)

• Quality control samples (QCS)

• Laboratory fortified sample matrix (LFSM)

• Sample handling requirements

• Uploading data to SDWARS

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 36 of 50
January 2016 U.S. Environmental Protection Agency 73

General Procedure

• Step 1: Request to Participate

• Step 2: Registration

• Step 3: Application Package

• Step 4: EPA Review of Application Package

• Step 5: Proficiency Testing (PT)

• Step 6: Written EPA approval

January 2016 U.S. Environmental Protection Agency 74

Step 1 - Request to Participate

• Submit a written request to EPA Laboratory

Approval Coordinator

• UCMR_Sampling_Coordinator@epa.gov

• EPA provides:

• Registration material

• Customized application package

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 37 of 50
January 2016 U.S. Environmental Protection Agency 75

Step 2 - Registration

• Complete registration sheet:

• List of the UCMR 4 methods that the laboratory is seeking

approval

• Laboratory information

• Mailing and shipping address

• Contact information

• EPA will provide a UCMR-specific laboratory ID to each

participant

• Must complete and submit the necessary registration

forms within 60 days of publication of the final rule

January 2016 U.S. Environmental Protection Agency 76

Step 3 - Application Package

• Separate application for each method

• Application must include:

• Proof of current drinking water laboratory certification (for select

compliance monitoring methods)

• Personnel information

• QA information

• Information regarding analytical equipment and sample handling

procedures

• Data submission for each method (e.g., IDC study, QC sample results,

quantification reports)

• Confirmation on reporting to SDWARS

• Must complete and submit the necessary application materials

(method specific) within 120 days from publication of final rule

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 38 of 50
January 2016 U.S. Environmental Protection Agency 77

Step 4 - Review of Application Package

• EPA reviews application package

• If deficiencies are identified the lab will have an

opportunity to make corrective actions and submit new

application information

• If all requested information is present and acceptable,

EPA will notify the laboratory that they are eligible to

participate in corresponding PT studies

January 2016 U.S. Environmental Protection Agency 78

Step 5 - Proficiency Testing

• EPA provides method-specific PT samples

• Laboratories:

• Analyze PT sample(s) for each analyte and method

• If do not pass PT, may have another opportunity

• One successful PT per method

• No PT studies after monitoring begins

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 39 of 50
January 2016 U.S. Environmental Protection Agency 79

Step 6 – Written EPA Approval

• After successful participation in a PT study for a

specific method, EPA will notify the laboratory in

writing

• Before final rule is published, the laboratory will be

granted a “pending approval” contingent upon:

• Changes applied to the final rule

• Resolution of any findings from a laboratory audit

• Granted “final approval” after promulgation of the

final rule

January 2016 U.S. Environmental Protection Agency 80

Maintaining Approval

• Adhere to QA/QC measures in the methods, rule

language and the UCMR 4 Laboratory Approval

Manual

• Post occurrence data and required QC data via

SDWARS within prescribed time frame

• Successfully complete audits and meet all the

other stated conditions

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 40 of 50
January 2016 U.S. Environmental Protection Agency 81

MRLs

• MRL is an estimate of the quantitation level,

achievable with a 95% confidence, by at least 75% of

laboratories nationwide

• Established with data from several laboratories

performing LCMRL studies

• LCMRL – The lowest true concentration for which the

future recovery is predicted to fall between 50% to

150% with 99% confidence

• Estimate of lowest concentration at which measurements of

specified quality can be repeatedly made

• Simultaneous application of precision and accuracy

January 2016 U.S. Environmental Protection Agency 82

MRLs

• To achieve quality across laboratories, while

allowing for reasonable national laboratory

capacity

• MRLs are generally established as low as is

reasonable; typically lower than current HRLs and

health advisories

• EPA will consider raising MRLs if there is evidence

that a proposed MRL is unattainable or impractical

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 41 of 50
January 2016 U.S. Environmental Protection Agency 83

MRLs - Cyanotoxins

1-Contaminant

2-CAS Registry 

Number

3-Analytical Methods

4-Minimum Reporting 

Level

microcystin-LA 96180-79-9 EPA 544 0.008 μg/L

microcystin-LF 154037-70-4 EPA 544 0.006 μg/L

microcystin-LR 101043-37-2 EPA 544 0.02 μg/L

microcystin-LY 123304-10-9 EPA 544 0.009 μg/L

microcystin-RR 111755-37-4 EPA 544 0.006 μg/L

microcystin-YR 101064-48-6 EPA 544 0.02 μg/L

nodularin 118399-22-7 EPA 544 0.005 μg/L

total microcystin N/A ADDA ELISA 0.3 μg/L

anatoxin-a 64285-06-9 EPA 545 0.03 μg/L

cylindrospermopsin 143545-90-8 EPA 545 0.09 μg/L

January 2016 U.S. Environmental Protection Agency 84

MRLs – Metals

1-Contaminant

2-CAS Registry 

Number

3-Analytical Methods

4-Minimum Reporting 

Level

germanium 7440-56-4 EPA 200.8, ASTM D5673-

10, SM 3125

0.3 μg/L

manganese 7439-96-5 EPA 200.8, ASTM D5673-

10, SM 3125

0.4 μg/L

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 42 of 50
January 2016 U.S. Environmental Protection Agency 85

MRLs – Pesticides and Pesticide Byproduct

1-Contaminant

2-CAS Registry 

Number

3-Analytical 

Methods

4-Minimum 

Reporting Level

alpha-hexachlorocyclohexane 319-84-6 EPA 525.3 0.01 μg/L

chlorpyrifos 2921-88-2 EPA 525.3 0.03 μg/L

dimethipin 55290-64-7 EPA 525.3 0.2 μg/L

ethoprop 13194-48-4 EPA 525.3 0.03 μg/L

oxyfluorfen 42874-03-3 EPA 525.3 0.05 μg/L

profenofos 41198-08-7 EPA 525.3 0.3 μg/L

tebuconazole 107534-96-3 EPA 525.3 0.2 μg/L

total permethrin (cis- & trans-) 52645-53-1 EPA 525.3 0.04 μg/L

tribufos 78-48-8 EPA 525.3 0.07 μg/L

January 2016 U.S. Environmental Protection Agency 86

MRLs – Haloacetic Acids

1-Contaminant

2-CAS Registry 

Number

3-Analytical Methods

4-Minimum 

Reporting Level

bromochloroacetic acid (BCAA) 5589-96-8 EPA 552.3 or EPA 557 0.3 μg/L

bromodichloroacetic acid (BDCAA) 71133-14-7 EPA 552.3 or EPA 557 0.5 μg/L

chlorodibromoacetic acid (CDBAA) 5278-95-5 EPA 552.3 or EPA 557 0.3 μg/L

tribromoacetic acid (TBAA) 75-96-7 EPA 552.3 or EPA 557 2.0 μg/L

monobromoacetic acid (MBAA) 79-08-3 EPA 552.3 or EPA 557 0.3 μg/L

dibromoacetic acid (DBAA) 631-64-1 EPA 552.3 or EPA 557 0.3 μg/L

dichloroacetic acid (DCAA) 79-43-6 EPA 552.3 or EPA 557 0.2 μg/L

monochloroacetic acid (MCAA) 79-11-8 EPA 552.3 or EPA 557 2.0 μg/L

trichloroacetic acid (TCAA) 76-03-9 EPA 552.3 or EPA 557 0.5 μg/L

* Register for TOC and bromide 

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 43 of 50
January 2016 U.S. Environmental Protection Agency 87

MRLs – Alcohols

1-Contaminant

2-CAS Registry 

Number

3-Analytical Methods

4-Minimum Reporting 

Level

1-butanol 71-36-3 EPA 541 2.0 μg/L

2-methoxyethanol 109-86-4 EPA 541 0.4 μg/L

2-propen-1-ol 107-18-6 EPA 541 0.5 μg/L

January 2016 U.S. Environmental Protection Agency 88

MRLs – Semivolatile Organics

1-Contaminant

2-CAS Registry 

Number

3-Analytical Methods

4-Minimum Reporting 

Level

butylated 

hydroxyanisole

25013-16-5 EPA 530 0.03 μg/L

o-toluidine 95-53-4 EPA 530 0.007 μg/L

quinoline 91-22-5 EPA 530 0.02 μg/L

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 44 of 50
Submitting Public Comments

Brenda Parris, USEPA

January 2016 U.S. Environmental Protection Agency 90

Comment Process/Accessing Docket

• Go to http://www.regulations.gov

• Enter Docket ID EPA-HQ-OW-2015-0218

• Click Search button

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 45 of 50
January 2016 U.S. Environmental Protection Agency 91

Comment Process/Accessing Docket

• The UCMR 4 docket

should pop up on the

next screen

• Click on the Comment

Now button on right

hand side of the screen

January 2016 U.S. Environmental Protection Agency 92

Comment Process/Accessing Docket

• Enter comment and all

required information

on next screen

• Upload a document by

clicking on the Choose

files button

• Click on the Continue

button at the bottom

of the page to preview

your comment

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 46 of 50
January 2016 U.S. Environmental Protection Agency 93

Comment Process/Accessing Docket

• Once submitted, comments cannot be edited or

removed

• Do not electronically submit any information you

consider to be CBI

• Multimedia submissions (audio, video, etc.) must be

accompanied by a written comment

• Written comment is considered the official comment and

should include discussion of all points you wish to make

• EPA public comment policy is at:

http://www.epa.gov/dockets/commenting-epadockets

Statements from Webinar 

Participants

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 47 of 50
Name Organization

Lynn Thorp Clean Water Action

Steve Via AWWA

Paul Monroy Babcock Laboratories, Inc.

Amanda Foss GreenWater Lab

Andrew Eaton Eurofins Eaton Analytical

Charmaigne Cortesio Arizona Public Service

Cynthia Andrews-Tate Long Beach Water Department

Heide Bell City of O'Fallon

Kasi Clay City of Grand Prairie

Robert Holmes Akron Water Supply

Dave Dunaway ADEQ

Judy Schmidt City of Arvada

Danielle Bonham City of Vallejo

Zach Brown City of Sterling

Theresa Lutz MDWID

Jeff Martin City of Evanston

Steven Prazak City of Bend Utility Department

Melissa Simoncini Concord Public Works

Doug Sims Auburn Water System

John Allen BCWID#1

January 2016 U.S. Environmental Protection Agency 96

Closing Remarks

• Further information:

• Brenda D. Parris: parris.brenda@epa.gov

• Melissa Simic: simic.melissa@epa.gov

• Safe Drinking Water Hotline:

http://www.epa.gov/your-drinking-water/safedrinking-water-hotline

• Meeting materials were sent to all registered

participants

• If you did not receive a copy, please email

UCMRwebinar@cadmusgroup.com and we will send 

you a copy

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 48 of 50
January 2016 U.S. Environmental Protection Agency 97

Additional Information

January 2016 U.S. Environmental Protection Agency 98

Acronyms

Abbreviations and Acronyms

ADDA (2S, 3S, 8S, 9S, 4E, 6E)-3-amino-9-methoxy-2,6,8-trimethyl-10-phenyl-4, 6-decadienoic acid

DSMRT Distribution System Maximum Residence Time 

ELISA Enzyme-linked Immunosorbent Assay

EPTDS Entry Point to the Distribution System

GW Ground Water

GWRMP Ground Water Representative Monitoring Plan

GWUDI Ground Water Under the Direct Influence of Surface Water

HAA5 Dibromoacetic Acid, Dichloroacetic Acid, Monobromoacetic Acid, Monochloroacetic Acid, 

Trichloroacetic Acid

HAA6Br Bromochloroacetic Acid, Bromodichloroacetic Acid, Dibromoacetic Acid, 

Dibromochloroacetic Acid, Monobromoacetic Acid, Tribromoacetic Acid

HRL Health Reference Level

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 49 of 50
January 2016 U.S. Environmental Protection Agency 99

Acronyms

Abbreviations and Acronyms

IDC Initial Demonstration of Capability

LCMRL Lowest Concentration Minimum Reporting Level

MRL Minimum Reporting Level

PA Partnership Agreement

PT Proficiency Testing

SDWARS Safe Drinking Water Accession and Review System 

SDWIS/Fed Federal Safe Drinking Water Information System 

SMP State Monitoring Plan

SW Surface Water

TOC Total Organic Carbon

Proposal: Revisions to the Unregulated Contaminant Monitoring Rule (UCMR 4) Webinar Presentations 50 of 50